tag:theconversation.com,2011:/au/topics/lizards-2917/articlesLizards – The Conversation2023-11-21T13:27:15Ztag:theconversation.com,2011:article/2152222023-11-21T13:27:15Z2023-11-21T13:27:15ZClimate change is already forcing lizards, insects and other species to evolve – and most can’t keep up<figure><img src="https://images.theconversation.com/files/558259/original/file-20231108-29-upppm0.jpg?ixlib=rb-1.1.0&rect=2%2C2%2C1615%2C1069&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Temperature sensitivity makes western fence lizards vulnerable to climate change.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/blmoregon/47961427128">Greg Shine/BLM</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>Climate change is threatening the survival of plants and animals around the globe as temperatures rise and habitats change.</p>
<p>Some species have been able to meet the challenge with rapid evolutionary adaptation and other changes in behavior or physiology. Dark-colored dragonflies are <a href="https://doi.org/10.1073/pnas.2101458118">getting paler</a> in order to reduce the amount of heat they absorb from the sun. Mustard plants are <a href="https://doi.org/10.1098/rspb.2012.1051">flowering earlier</a> to take advantage of earlier snowmelt. Lizards are <a href="https://doi.org/10.1098/rsbl.2020.0625">becoming more cold-tolerant</a> to handle the extreme variability of our new climate.</p>
<p>However, scientific studies show that climate change is occurring much faster than species are changing.</p>
<figure class="align-center ">
<img alt="A tiny, royal blue fish with gold stripes looks into the camera. The downward slant of its mouth and shadow at the top of its eye give it an annoyed look." src="https://images.theconversation.com/files/558243/original/file-20231108-23-xs3oy9.jpg?ixlib=rb-1.1.0&rect=8%2C8%2C5599%2C3724&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/558243/original/file-20231108-23-xs3oy9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/558243/original/file-20231108-23-xs3oy9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/558243/original/file-20231108-23-xs3oy9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/558243/original/file-20231108-23-xs3oy9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/558243/original/file-20231108-23-xs3oy9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/558243/original/file-20231108-23-xs3oy9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Zebrafish have evolved to thrive in water a degree or so warmer than normal, but they struggle to survive at higher temperatures.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/brachydanio-rerio-royalty-free-image/154930602?adppopup=true">isoft/E+ Getty Images</a></span>
</figcaption>
</figure>
<h2>What is evolutionary adaptation?</h2>
<p>The word “adaptation” is used in many ways by climate scientists, but it has a very specific meaning to biologists: It refers to genetic changes that are passed on from one generation to the next and improve a species’ ability to survive in its environment.</p>
<p>These genetic modifications make evolutionary adaptation different from “acclimation” or “acclimatization,” which involve advantages that are not passed on to offspring. For example, when people move to high-altitude cities, they <a href="http://dx.doi.org/10.1136/bjsports-2013-092840">start producing more red blood cells</a> as they acclimate to the low oxygen.</p>
<p>All over the world, plants and animals have adapted to many different warm and dry habitats, prompting scientists to <a href="https://doi.org/10.1098/rstb.2018.0176">question</a> <a href="https://doi.org/10.1038/s41586-019-1520-9">whether</a> <a href="https://doi.org/10.1111/gcb.14881">species</a> <a href="https://doi.org/10.1073/pnas.1406314111">might</a> <a href="https://doi.org/10.1111/evo.13862">also</a> <a href="https://doi.org/10.1126/science.1063656">adapt</a> <a href="https://doi.org/10.1073/pnas.0608379104">to</a> <a href="https://doi.org/10.1111/ele.14072">our</a> <a href="https://doi.org/10.1126/science.aba9287">rapidly</a> <a href="https://doi.org/10.1126/science.abj7484">changing</a> <a href="https://doi.org/10.1126/science.aaf3343">climate</a>, <a href="https://doi.org/10.1038/nclimate2628">too</a>.</p>
<p>Thus far, the answer <a href="https://doi.org/10.1002/wcc.852">seems to be no</a> for most species.</p>
<h2>Evolving, fast and slow</h2>
<p>A <a href="https://doi.org/10.1038/s41467-019-10924-4">recent study</a> of the populations of 19 bird and mammal species, including owls and deer, shows one potential barrier to adaptation. </p>
<p>In animals that take several years to reach breeding age, the climate has already shifted by the time their offspring are born. Genes that gave the parents an advantage – like hatching at exactly the right time or growing to the best size – are no longer as beneficial for the offspring.</p>
<p>Populations of these slow-maturing animals are adapting to climate change, but not enough during each generation to thrive in the changing conditions. In fact, the rate of evolution is so mismatched to the rate of global warming that the study’s authors estimate that nearly 70% of the local populations they studied are already vulnerable to climate-driven extinction over the coming decades.</p>
<figure class="align-center ">
<img alt="A dragonfly with dark bands on its wings." src="https://images.theconversation.com/files/558246/original/file-20231108-27-yipcvj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/558246/original/file-20231108-27-yipcvj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=408&fit=crop&dpr=1 600w, https://images.theconversation.com/files/558246/original/file-20231108-27-yipcvj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=408&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/558246/original/file-20231108-27-yipcvj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=408&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/558246/original/file-20231108-27-yipcvj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=512&fit=crop&dpr=1 754w, https://images.theconversation.com/files/558246/original/file-20231108-27-yipcvj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=512&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/558246/original/file-20231108-27-yipcvj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=512&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Black bands on dragonflies heat up their bodies. Research shows some dragonflies have evolved smaller black bands as the climate warms.</span>
<span class="attribution"><span class="source">Michael P. Moore</span></span>
</figcaption>
</figure>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/558248/original/file-20231108-27-nr1728.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A heat map clearly shows that the dark bands on the wings absorb more heat." src="https://images.theconversation.com/files/558248/original/file-20231108-27-nr1728.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/558248/original/file-20231108-27-nr1728.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/558248/original/file-20231108-27-nr1728.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/558248/original/file-20231108-27-nr1728.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/558248/original/file-20231108-27-nr1728.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/558248/original/file-20231108-27-nr1728.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/558248/original/file-20231108-27-nr1728.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">In this heat map of the same dragonfly, white areas are the warmest and purple areas are cooler. The dark bands on the wings stand out.</span>
<span class="attribution"><span class="source">Michael P. Moore</span></span>
</figcaption>
</figure>
<p>Small-bodied animals, such as many fish, insects and plankton, typically mature quickly. Yet, recent research on <a href="https://doi.org/10.1073/pnas.2011419117">small fish</a> and a type of <a href="https://doi.org/10.1098/rspb.2011.0542">fast-maturing plankton called a copepod</a> revealed another hurdle for rapid genetic adaptation to climate change.</p>
<p>Many species possess genes that permit them to live in environments that are 1 to 2 degrees Celsius (about 2 to 4 Fahrenheit) warmer than today, but new genetic mutations must arise to enable survival if climates reach 4 to 5 C (about 7 to 9 F) warmer, as is possible in some regions, particularly if greenhouse gas emissions continue at a high rate.</p>
<p>To test species’ resilience, scientists warmed populations of these fast-maturing species over many generations to observe their genetic changes. They found that both the copepods and the small fish were able to adapt to the first couple degrees of warming, but populations soon went extinct above that. This was because genetic mutations that increased their ability to live in hotter conditions occurred at a slower rate than the temperatures rose.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/558242/original/file-20231108-29-dkylc9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A tiny nearly translucent oval creature with a tail and egg sacks trailing behind it." src="https://images.theconversation.com/files/558242/original/file-20231108-29-dkylc9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/558242/original/file-20231108-29-dkylc9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=397&fit=crop&dpr=1 600w, https://images.theconversation.com/files/558242/original/file-20231108-29-dkylc9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=397&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/558242/original/file-20231108-29-dkylc9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=397&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/558242/original/file-20231108-29-dkylc9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=500&fit=crop&dpr=1 754w, https://images.theconversation.com/files/558242/original/file-20231108-29-dkylc9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=500&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/558242/original/file-20231108-29-dkylc9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=500&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A live copepod with egg sacs at 10 times magnification. These ocean creatures produce new generations quickly, allowing for speedier evolution.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/copepod-micrograph-royalty-free-image/170025374?adppopup=true">NNehring/E+ Getty Images</a></span>
</figcaption>
</figure>
<p>Cold-blooded species, such as lizards, frogs and fish, are especially vulnerable to climate change because they have a limited capacity to regulate their own body temperatures. Their ability to evolve in response to climate change is expected to be critical for their survival.</p>
<p>However, rapid adaptation to climate change often comes <a href="https://doi.org/10.1007/BF02984069">at a cost</a>: Populations get smaller due to the deaths of individuals that cannot tolerate new, hotter temperatures. Therefore, even if species do evolve to survive with climate change, their smaller populations may still go extinct due to problems such as inbreeding, harmful new mutations or plain old bad luck, such as a disease epidemic.</p>
<p><a href="https://doi.org/10.1126/science.1184695">In a now-classic study</a>, researchers studying lizards in Mexico discovered that the high death rates of just the heat-sensitive individuals – representing only a subset of the entire population – caused 12% of all lizard populations in Mexico to go extinct between 1975 and 2009. Even with some heat-tolerant adult lizards surviving in each population under the warmer conditions, the researchers estimated climate change would kill so many heat-sensitive adults within each population that 54% of all populations would go extinct by 2080.</p>
<h2>Evolutionary adaptation isn’t species’ only option</h2>
<p>Another way species adjust to rising temperatures is acclimation, sometimes called “phenotypic plasticity.” For example, <a href="https://doi.org/10.1126/science.1157174">great tits in the U.K.</a> – small birds that are common in yards and forests – lay their eggs earlier in warmer years so that their nestlings hatch right as the winter weather ends, no matter when that happens.</p>
<figure class="align-center ">
<img alt="A small bird with a yellow body and black head with white cheeks sits on a branch." src="https://images.theconversation.com/files/558258/original/file-20231108-21-3e6t6i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/558258/original/file-20231108-21-3e6t6i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=375&fit=crop&dpr=1 600w, https://images.theconversation.com/files/558258/original/file-20231108-21-3e6t6i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=375&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/558258/original/file-20231108-21-3e6t6i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=375&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/558258/original/file-20231108-21-3e6t6i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=471&fit=crop&dpr=1 754w, https://images.theconversation.com/files/558258/original/file-20231108-21-3e6t6i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=471&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/558258/original/file-20231108-21-3e6t6i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=471&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A great tit – <em>Parus major</em>. In the U.K., these common birds have been laying their eggs earlier in warm years.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/hedera_baltica/49433487712/in">Hedera.Baltica via Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>However, a <a href="https://www.nature.com/articles/s41467-022-32953-2">recent analysis</a> of more than 100 beetle, grasshopper and other insect species all over the world found that acclimation may not help those species enough. The study’s authors found that the species they reviewed gained an average of only 0.1 C (about 0.2 F) greater heat tolerance when acclimating to 1 C (about 2 F) warmer air temperatures during their development. Thus, the rate of global warming seems to be outstripping species’ abilities to acclimate, too.</p>
<p>Plants and animals could also escape the impacts of global warming by migrating to cooler habitats. A <a href="https://doi.org/10.1038/s41559-020-1198-2">global analysis</a> of more than 12,000 different plants and animal species recently showed that many species are migrating toward the poles fast enough to keep pace with rising temperatures, and many <a href="https://doi.org/10.1111/ele.13762">tropical species are moving upslope</a> to higher elevations as well.</p>
<p>Nonetheless, migration has its limits. Research shows that <a href="https://doi.org/10.1073/pnas.1804224115">tropical birds that already live high in the mountains could be doomed</a> because there is no room for them to migrate any farther upward. Tropical species, therefore, may be on what the authors call an “escalator to extinction.”</p>
<figure class="align-center ">
<img alt="A yellow-and-black moth sits on a yellow flower in an alpine field with snow-covered mountains in the background." src="https://images.theconversation.com/files/558253/original/file-20231108-21-ad3ofx.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/558253/original/file-20231108-21-ad3ofx.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=789&fit=crop&dpr=1 600w, https://images.theconversation.com/files/558253/original/file-20231108-21-ad3ofx.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=789&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/558253/original/file-20231108-21-ad3ofx.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=789&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/558253/original/file-20231108-21-ad3ofx.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=992&fit=crop&dpr=1 754w, https://images.theconversation.com/files/558253/original/file-20231108-21-ad3ofx.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=992&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/558253/original/file-20231108-21-ad3ofx.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=992&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Police car moths living at high elevations have little room to migrate to escape increasing heat.</span>
<span class="attribution"><span class="source">Michael P. Moore</span></span>
</figcaption>
</figure>
<p>High-latitude and high-elevation habitats also present numerous challenges for species to overcome besides temperature. Our own research across 800 species of insects all over the Earth shows that butterflies, bees and other flying insects are <a href="https://doi.org/10.1038/s41558-023-01794-2">especially hindered from migrating to higher elevations</a> because there is not enough oxygen for them to survive. </p>
<h2>Many species lack obvious climate strategies</h2>
<p>Overall, evolutionary adaptation appears to help lessen the impacts of global warming, but the evidence thus far shows that it is insufficient to overcome current rates of climate change. Acclimation and migration provide faster solutions, but research shows that those may not be enough, either.</p>
<p>Of course, not all evolution is driven by warming temperatures. Plant and animal species appear to be also gradually adapting to other kinds of environments, including <a href="https://doi.org/10.1111/evo.14191">human-created ones like cities</a>. But the fast pace of global warming makes it <a href="https://nca2023.globalchange.gov/chapter/8#fig-8-2">one of the major threats</a> that species must respond to immediately.</p>
<p>The <a href="https://nca2023.globalchange.gov/chapter/8#fig-8-2">evidence indicates</a> that humanity cannot simply assume that plants and animals will be able to save themselves from climate change. To protect these species, humans will have to stop the activities that are fueling climate change.</p><img src="https://counter.theconversation.com/content/215222/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>From dark dragonflies becoming paler to plants flowering earlier, some species are slowly evolving with the climate. Evolutionary biologists explain why few will evolve fast enough.Michael P. Moore, Assistant Professor of Biology, University of Colorado DenverJames T. Stroud, Assistant Professor of Ecology and Evolution, Georgia Institute of TechnologyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2080972023-06-25T05:55:02Z2023-06-25T05:55:02ZVictoria has rediscovered a dragon – how do we secure its future?<p>The Victorian grassland earless dragon (<em><a href="https://royalsocietypublishing.org/doi/10.1098/rsos.190233">Tympanocryptis pinguicolla</a></em>), not seen <a href="https://theconversation.com/why-were-not-giving-up-the-search-for-mainland-australias-first-extinct-lizard-117831">since 1969</a>, has been <a href="https://www.premier.vic.gov.au/reptile-thought-be-extinct-rediscovered-victoria">found in grasslands</a> west of Melbourne. No need to fear this dragon, though; these lizards are just 15cm long fully grown. </p>
<p>The dragon is Australia’s most imperilled scaled reptile. This is an extraordinary second chance. The <a href="https://theconversation.com/still-here-night-parrot-rediscovery-in-wa-raises-questions-for-mining-75384">rediscovery of a species</a> thought to be extinct inspires hope of finding other <a href="https://theconversation.com/extinct-but-not-gone-the-thylacine-continues-to-fascinate-us-201865">lost treasures</a> like the Tassie tiger. </p>
<p>But rediscovery only happens because a species has become so scarce it has eluded even the experts who know best where to look. To save it from extinction, three things must happen quickly: </p>
<ol>
<li><p>intensive care – create a conservation breeding population, manage its remaining genetic diversity, and breed enough individuals to return to the wild</p></li>
<li><p>within the species’ range, protect habitats of the size, quality and quantity needed to support self-sustaining populations</p></li>
<li><p>restore and manage these habitats, reduce threats, reintroduce the dragons and monitor outcomes to ensure the species’ long-term viability.</p></li>
</ol>
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Read more:
<a href="https://theconversation.com/why-were-not-giving-up-the-search-for-mainland-australias-first-extinct-lizard-117831">Why we're not giving up the search for mainland Australia's 'first extinct lizard'</a>
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<h2>Intensive care</h2>
<p>This first step is to set up a climate-controlled, disease-free conservation breeding facility, run by the ICU doctors and nurses of conservation. It’s a tragedy that the only option is to take the last few individuals of a species from the wild to secure its future. With that decision made, it is essential they receive the best possible care. </p>
<p>Fortunately, Melbourne has experts who know how to build and run such facilities, reintroduce species to the wild and monitor their recovery. In this way, Zoos Victoria and collaborators have over the past decade averted the extinction of the mountain pygmy possum, lowland Leadbeater’s possum, helmeted honeyeaters, Baw Baw frog, southern corroboree frog and spotted tree frog. </p>
<p>This work involves setting up, maintaining and staffing such a facility, as well as surveys to locate and move individuals into captive breeding. Based on experience with <a href="https://www.smh.com.au/environment/conservation/a-beacon-of-hope-frog-saving-push-spawns-zoo-s-500k-breeding-centre-20220930-p5bm7m.html">endangered frogs</a>, plus the extra costs of outdoor enclosures, the cost will be around A$2 million over the next five years.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/533597/original/file-20230622-19-btp646.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="biological drawings of the grassland earless dragon" src="https://images.theconversation.com/files/533597/original/file-20230622-19-btp646.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/533597/original/file-20230622-19-btp646.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=370&fit=crop&dpr=1 600w, https://images.theconversation.com/files/533597/original/file-20230622-19-btp646.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=370&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/533597/original/file-20230622-19-btp646.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=370&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/533597/original/file-20230622-19-btp646.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=465&fit=crop&dpr=1 754w, https://images.theconversation.com/files/533597/original/file-20230622-19-btp646.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=465&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/533597/original/file-20230622-19-btp646.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=465&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The grassland earless dragon was feared extinct, with only museum specimens, photos and drawings remaining.</span>
<span class="attribution"><a class="source" href="https://collections.museumsvictoria.com.au/articles/16665">John James Wild/Museums Victoria</a></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/hundreds-of-australian-lizard-species-are-barely-known-to-science-many-may-face-extinction-161572">Hundreds of Australian lizard species are barely known to science. Many may face extinction</a>
</strong>
</em>
</p>
<hr>
<h2>Securing habitat</h2>
<p>Merely keeping a species alive in zoos <a href="https://link.springer.com/article/10.1007/s10806-015-9537-z">is not conservation</a>. Self-sustaining wild populations must be established to recover a species. This is where complexity, uncertainty and economics really bite. </p>
<p>The dragon has only ever been found in the critically endangered ecosystem known as the <a href="https://theconversation.com/ecocheck-victorias-flower-strewn-western-plains-could-be-swamped-by-development-57127">basalt plains grasslands</a>. Agriculture and housing development have reduced these grasslands to <a href="https://www.publish.csiro.au/book/7219/">less than 3%</a> of their pre-European extent. Most of what remains is on private land. </p>
<p>The dragon’s long-term fate depends on managing the site where it was found and any areas nearby where dragons are living. We also need substantial new areas of suitable plains grasslands as conservation reserves where captive-bred animals can be released. </p>
<p><a href="https://www.nature.com/articles/npre.2009.3387.1.pdf">Research</a> tells us we need at least six independent, self-sustaining populations for the dragon to stand a chance of persisting for at least the next 50 years. Even if well-managed, some populations will occasionally be lost to disease, predation, hot fires, or other chance events. </p>
<p>Individuals will have to be released back into those areas once the areas recover and can support the species again. In pre-European times, animals could naturally migrate back into such places. Today, habitats are too fragmented for that to happen. </p>
<p>Unfortunately, basalt plains grasslands continue to be lost to <a href="https://www.abc.net.au/news/2022-08-11/melbourne-grassland-destroyed-developer-conservation-tension/101275526">legal and illegal clearing</a>, the use of fertilisers that favour exotic grasses, weed invasion, rock removal, intensive grazing and the loss of regular low-intensity “cool” fires historically <a href="https://theconversation.com/before-the-colonists-came-we-burned-small-and-burned-often-to-avoid-big-fires-its-time-to-relearn-cultural-burning-201475">used by Traditional Owners</a>. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/before-the-colonists-came-we-burned-small-and-burned-often-to-avoid-big-fires-its-time-to-relearn-cultural-burning-201475">Before the colonists came, we burned small and burned often to avoid big fires. It's time to relearn cultural burning</a>
</strong>
</em>
</p>
<hr>
<p>To make matters worse, the Victorian government has over the past decade <a href="https://www.theage.com.au/national/victoria/broken-promises-turn-fragile-grasslands-into-unprotected-basketcase-20200617-p553p4.html">broken its promise</a> to <a href="https://www.audit.vic.gov.au/sites/default/files/2020-06/20200617-Endangered-Grasslands-report.pdf">set aside large areas</a> of western plains grasslands as conservation reserves. </p>
<p>Securing new conservation areas will be expensive given the competing demands for this land. However, the government has received offset payments from developers when they (legally) destroy grasslands to build houses. It’s time to use those funds to create the reserves the dragon and other endangered grassland species need to survive. </p>
<p>We estimate securing six high-quality grasslands of at least 100 hectares each will cost at least $30 million.</p>
<figure class="align-center ">
<img alt="grassy, rock-strewn hillside with a tree on the horizon" src="https://images.theconversation.com/files/533622/original/file-20230623-5432-ozzzks.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/533622/original/file-20230623-5432-ozzzks.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/533622/original/file-20230623-5432-ozzzks.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/533622/original/file-20230623-5432-ozzzks.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/533622/original/file-20230623-5432-ozzzks.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/533622/original/file-20230623-5432-ozzzks.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/533622/original/file-20230623-5432-ozzzks.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The biggest cost of ensuring the survival of the dragon and other endangered species will be securing enough of their grassland habitat.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/elizabeth_donoghue/2851275651/">Elizabeth O'Donoghue/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-vast-majority-of-melburnians-want-more-nature-in-their-city-despite-a-puzzling-north-south-divide-206938">The vast majority of Melburnians want more nature in their city, despite a puzzling north-south divide</a>
</strong>
</em>
</p>
<hr>
<h2>Managing threats and restoring habitats</h2>
<p>These reserves will need careful and active management. In the absence of frequent cool fires, and in the presence of invasive weeds and animal pests, these areas will lose the plant species that make them special and beautiful. Weeds, cats, foxes, dogs and rabbits all create unsuitable habitat for dragons. </p>
<p>Many of these grasslands are so degraded they need a lot of restoration work, almost starting from bare soil. </p>
<p>Weed control and fire management to maintain six 100-hectare reserves as suitable habitat for dragons will cost around $2.4 million a year. These reserves would of course be home to many more grassland animals and plants, including <a href="https://theconversation.com/ecocheck-victorias-flower-strewn-western-plains-could-be-swamped-by-development-57127">other endangered species</a> such as the <a href="https://theconversation.com/i-realised-the-fat-tailed-dunnart-was-under-threat-heres-how-i-got-the-species-officially-listed-200632">fat-tailed dunnart</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/ecocheck-victorias-flower-strewn-western-plains-could-be-swamped-by-development-57127">EcoCheck: Victoria's flower-strewn western plains could be swamped by development</a>
</strong>
</em>
</p>
<hr>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/533592/original/file-20230622-23-4p9jiq.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="map showing range of grasslands earless dragon to the west of Melbourne" src="https://images.theconversation.com/files/533592/original/file-20230622-23-4p9jiq.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/533592/original/file-20230622-23-4p9jiq.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=449&fit=crop&dpr=1 600w, https://images.theconversation.com/files/533592/original/file-20230622-23-4p9jiq.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=449&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/533592/original/file-20230622-23-4p9jiq.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=449&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/533592/original/file-20230622-23-4p9jiq.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=564&fit=crop&dpr=1 754w, https://images.theconversation.com/files/533592/original/file-20230622-23-4p9jiq.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=564&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/533592/original/file-20230622-23-4p9jiq.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=564&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Development has destroyed most of the grassland habitat across the dragon’s former range.</span>
<span class="attribution"><a class="source" href="http://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=66727">Commonwealth DCCEEW</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>We can’t be sure of the exact costs of buying, restoring and managing grasslands. Our estimates assume, for example, the sites contain most grassland plant species. If areas were being restored from bare soil, ten-year restoration and management costs would more than double. </p>
<p>Other uncertainties include land prices, the costs of weed and pest control and fire management, and the possible need to help insect populations establish as a sustainable source of dragon food.</p>
<h2>We can afford to save the dragon</h2>
<p>The whole program is likely to cost around $56 million over ten years. More than half the cost involves buying highly sought-after properties. </p>
<p>If this sounds like a lot of money, consider that Australians spend over <a href="https://www.petfoodindustry.com/news-newsletters/pet-food-news/article/15469415/national-survey-reveals-australians-spending-on-pets">$30 billion</a> a year on pet care. Just the GST on that spending ($3 billion) would cover the annual <a href="https://conbio.onlinelibrary.wiley.com/doi/full/10.1111/conl.12682">cost of conserving</a> most of our <a href="https://www.environment.gov.au/cgi-bin/sprat/public/publicthreatenedlist.pl">1,900 or so endangered species</a> (most don’t have the dragon’s expensive taste in real estate). As a nation, we can afford to save the dragon and <a href="https://theconversation.com/if-the-budget-ditched-the-stage-3-tax-cuts-australia-could-save-every-threatened-species-and-lots-more-205305">most of its endangered friends</a>, as <a href="https://www.legislation.gov.au/Details/C2021C00182">the law requires</a>.</p><img src="https://counter.theconversation.com/content/208097/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Brendan Wintle has received funding from the Australian Research Council, the Victorian, NSW and Queensland governments, the Commonwealth National Environmental Science Program, the Ian Potter Foundation, the Hermon Slade Foundation, and the Australian Conservation Foundation. He is a board director of Zoos Victoria and a lead councillor of the Biodiversity Council.</span></em></p><p class="fine-print"><em><span>Sarah Bekessy receives funding from the Australian Research Council, the National Health and Medical Research Council, the Ian Potter Foundation and the European Commission. She is a lead councillor of the Biodiversity Council, a board member of Bush Heritage Australia, a member of WWF's Eminent Scientists Group and a member of the Advisory Group for Wood for Good.</span></em></p>The successful quest to find a species last seen more than 50 years ago has added to the urgency of protecting the vanishing grassland habitat of a lizard that had been feared extinct.Brendan Wintle, Professor in Conservation Science, School of Ecosystem and Forest Science, The University of MelbourneSarah Bekessy, Professor in Sustainability and Urban Planning, Leader, Interdisciplinary Conservation Science Research Group (ICON Science), RMIT UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2067642023-06-13T23:01:57Z2023-06-13T23:01:57ZMeet the biggest and most bizarre skink ever found in Australia. It became extinct 47,000 years ago<figure><img src="https://images.theconversation.com/files/529338/original/file-20230531-29-zcqbue.jpg?ixlib=rb-1.1.0&rect=120%2C42%2C1566%2C1104&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Katrina Kenny</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Many of the giant marsupials and birds that roamed ancient Australia had vanished by 40,000 years ago. While the duration and drivers of these extinctions <a href="https://theconversation.com/did-people-or-climate-kill-off-the-megafauna-actually-it-was-both-127803">remain debated</a>, fossils clearly show the continent lost a host of creatures which would have dwarfed humans, such as short-faced kangaroos, diprotodons, “<a href="https://theconversation.com/fossil-find-reveals-giant-prehistoric-thunder-birds-were-riddled-with-bone-disease-173745">thunder birds</a>” and giant goannas. </p>
<p>Our <a href="https://doi.org/10.1098/rspb.2023.0704">study published today</a> in Proceedings of the Royal Society B suggests these end-Pleistocene extinctions also affected smaller creatures such as lizards. These animals comprise most of biodiversity and biomass.</p>
<h2>A bizarre giant among tiny lizards</h2>
<p>The most diverse land vertebrates in modern Australia are <a href="https://www.australiangeographic.com.au/topics/wildlife/2017/11/scale-tales-guide-to-aussie-skinks/">skinks</a>, which are typically the tiny, nondescript brown lizards that scurry among leaf litter. </p>
<p>There are some larger and more charismatic forms, such as blue-tongues and <a href="https://australian.museum/learn/animals/reptiles/shingleback-lizard/">shinglebacks</a> (also known as sleepy lizards or bobtails). However, even these are dwarfed by our new fossil skink, <em>Tiliqua frangens</em> (or Frangens), which was more than 60cm long and weighed more than 2kg. This 1,000 times heavier than your typical garden skink.</p>
<p>Frangens was bizarre in many ways: it was covered in very thick, spiky armour and had an extremely wide but blunt skull. Frangens was an enlarged and exaggerated version of its closest living relative, the shingleback, which has these traits but to a much lesser degree. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/529337/original/file-20230531-29-8mynu8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/529337/original/file-20230531-29-8mynu8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/529337/original/file-20230531-29-8mynu8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=373&fit=crop&dpr=1 600w, https://images.theconversation.com/files/529337/original/file-20230531-29-8mynu8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=373&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/529337/original/file-20230531-29-8mynu8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=373&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/529337/original/file-20230531-29-8mynu8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=469&fit=crop&dpr=1 754w, https://images.theconversation.com/files/529337/original/file-20230531-29-8mynu8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=469&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/529337/original/file-20230531-29-8mynu8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=469&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A pair of <em>Tiliqua frangens</em>, the giant armoured skink, shown for scale next to a typical living skink, <em>Lampropholis guichenoti</em> (bottom right). Based on its closest living relatives such as shinglebacks and blue-tongues, Frangens would most likely have had a blue tongue, and might have exhibited pair bonding.</span>
<span class="attribution"><span class="source">Katrina Kenny, Author provided</span></span>
</figcaption>
</figure>
<p>While our large mammalian and avian megafauna are well studied, smaller fossil lizards and snakes are often overlooked. Most of the fossils used to piece together this extinct critter have been sitting in museum collections for decades - some for more than a century.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/humans-coexisted-with-three-tonne-marsupials-and-lizards-as-long-as-cars-in-ancient-australia-138534">Humans coexisted with three-tonne marsupials and lizards as long as cars in ancient Australia</a>
</strong>
</em>
</p>
<hr>
<h2>A jigsaw puzzle with pieces scattered all over Australia</h2>
<p>The first two pieces of this creature, a partial lower jaw and skull-roof bone, were found separately in spoil heaps at <a href="https://www.wellingtoncaves.com.au/">Wellington Caves</a>, about 200km west of Sydney in 1995 and 2008. These fragments were scientifically described as different species in <a href="https://doi.org/10.1670/08-126R.1">2009</a> and <a href="https://doi.org/10.1080/03115518.2012.715326">2012</a>.</p>
<p>Then in 2016, palaeontologists from Flinders University began finding more fossils of a large skink in Cathedral Cave at Wellington Caves. Frangens immediately stood out not just for its unusual size, but for its spikey body armour, abundant in the dig site yet oddly never reported before. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/529736/original/file-20230602-21-6cutjo.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Interior of a cave chamber, with a large stalagmite reaching from the floor to the roof" src="https://images.theconversation.com/files/529736/original/file-20230602-21-6cutjo.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/529736/original/file-20230602-21-6cutjo.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/529736/original/file-20230602-21-6cutjo.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/529736/original/file-20230602-21-6cutjo.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/529736/original/file-20230602-21-6cutjo.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/529736/original/file-20230602-21-6cutjo.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/529736/original/file-20230602-21-6cutjo.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Cathedral Cave, Wellington Caves. The fossil dig, where many of the Frangens remains were found, is located to the left of the large brightly-lit stalagmite. The lizards (and other surface creatures) fell into the cave through a now-closed roof entrance, and were unable to get out.</span>
<span class="attribution"><span class="source">Diana Fusco, Author provided</span></span>
</figcaption>
</figure>
<p>A study tour of the palaeontology sections of the Australian, South Australian and Melbourne museums brought to light the importance of their collections. Sitting in drawers of unidentified reptiles were near-complete jaws, perfectly preserved braincases, and chunks of fused armour plating from the head of Frangens.</p>
<p>The Queensland Museum had put aside a specimen representing most of a single individual, waiting for someone with the patience and expertise to piece it together.</p>
<p>It became clear the original lower jaw and skull roof, plus all the subsequent material, belonged to a single species.</p>
<p>This wealth of fossils also broadened our understanding of the spatial and temporal range of this highly distinct lizard. Frangens fossils have been recovered from southeastern Queensland through to the northern banks of the Murray River in New South Wales. The fossils range in age from at least 2 million years to 47,000 years old. So Frangens was part of the fauna when the First Peoples arrived. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/530028/original/file-20230605-27-10occ9.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A black silhouette of a chunky shingleback skink viewed from directly above, with some of the fossil bones placed where they would have been in-life. An inset shows the side-view of a single piece of the armour plating, with Frangens armour showing a tall spine" src="https://images.theconversation.com/files/530028/original/file-20230605-27-10occ9.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/530028/original/file-20230605-27-10occ9.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=292&fit=crop&dpr=1 600w, https://images.theconversation.com/files/530028/original/file-20230605-27-10occ9.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=292&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/530028/original/file-20230605-27-10occ9.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=292&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/530028/original/file-20230605-27-10occ9.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=367&fit=crop&dpr=1 754w, https://images.theconversation.com/files/530028/original/file-20230605-27-10occ9.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=367&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/530028/original/file-20230605-27-10occ9.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=367&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption"><em>T. frangens</em> was a heavy-set shingleback, much wider than living blue-tongued lizards and with giant spiked scales to protect it from predators while it foraged in the open.</span>
<span class="attribution"><span class="source">Author provided</span></span>
</figcaption>
</figure>
<h2>A lost lizard that functioned more like a tortoise?</h2>
<p>Australia has never had small land tortoises. Tortoises are completely absent in modern Australia, while the famously large <a href="https://en.wikipedia.org/wiki/Meiolaniidae">meiolaniid turtles</a> are extinct.</p>
<p>It is possible that in Australia, the heavily armoured, slow-moving Frangens filled the ecological niche that small tortoises occupy on other continents. </p>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/529358/original/file-20230531-21-k18gvn.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/529358/original/file-20230531-21-k18gvn.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=610&fit=crop&dpr=1 600w, https://images.theconversation.com/files/529358/original/file-20230531-21-k18gvn.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=610&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/529358/original/file-20230531-21-k18gvn.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=610&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/529358/original/file-20230531-21-k18gvn.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=767&fit=crop&dpr=1 754w, https://images.theconversation.com/files/529358/original/file-20230531-21-k18gvn.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=767&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/529358/original/file-20230531-21-k18gvn.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=767&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The shingleback or sleepy lizard (<em>Tiliqua rugosa</em>) is the nearest living relative of the giant armoured skink <em>T. frangens</em>, and shares many similarities.</span>
<span class="attribution"><span class="source">Michael Lee, Author provided</span></span>
</figcaption>
</figure>
<p>Intriguingly, in none of the fossil sites we have explored, do Frangens and the modern shingleback co-occur. Instead, only after Frangens went extinct did shinglebacks expand northward and increase in size: those ranging from the Murray to southeastern Queensland are among Australia’s largest living skinks (reaching up to 1kg).</p>
<p>Nature abhors a vacuum, so these shinglebacks might be growing big to fill the gap left by Frangens, which in turn previously filled the gap caused by the absence of small tortoises.</p>
<p>Furthermore, Frangens was not alone, but was part of a cohort of giant skinks, none of which survived past the end-Pleistocene extinctions.</p>
<p>These fossils show that the extinctions were not confined to “megafauna” – the largest examples of the largest groups. Rather, even some smaller animals such as skinks once had (relatively) large forms, which perished in the late Pleistocene along with giant marsupials and flightless birds.</p><img src="https://counter.theconversation.com/content/206764/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mike Lee receives funding from the Australian Research Council, Flinders University and the Royal Society of South Australia</span></em></p><p class="fine-print"><em><span>Diana Fusco received funding from the Maxim Foundation and the Royal Society of South Australia, and was supported by an Australian Research Training Program stipend for this project. The Cathedral Cave project was initially funded by the Australian Research Council. </span></em></p><p class="fine-print"><em><span>Kailah Thorn received funding from the Royal Society of South Australia, and was supported by an Australian Research Training Program stipend for this project.</span></em></p>Researchers have found an armoured fossil skink 1,000 times heavier than the ones in your garden. Its closest living relative is the shingleback lizard.Mike Lee, Professor in Evolutionary Biology (jointly appointed with South Australian Museum), Flinders UniversityDiana Fusco, Casual academic, Flinders UniversityKailah Thorn, Technical Officer, Western Australian MuseumLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1862752023-01-13T13:30:36Z2023-01-13T13:30:36ZNative eastern fence lizards changed their bodies and behavior in response to invasive red imported fire ants<figure><img src="https://images.theconversation.com/files/503699/original/file-20230109-5266-ezc4go.jpg?ixlib=rb-1.1.0&rect=191%2C97%2C2151%2C1645&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Lizards that do or do not share space with invasive fire ants will react differently to this scenario. </span> <span class="attribution"><span class="source">Tracy Langkilde and Travis Robbins</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>An eastern fence lizard basking in the sun feels a small red ant walk over its back. Not hungry, it ignores the insect. Soon there are lots of ants crawling up its legs, biting the scales that usually protect it and inserting their stingers in its soft underlying flesh.</p>
<p>Not having evolved with this threat, the lizard adopts its typical defensive posture of lying flat and closing its eyes, counting on its natural camouflage to protect it. This can be a deadly decision, though. As few as 12 of these ants can kill an adult lizard in <a href="https://doi.org/10.1890/08-0355.1">less than a minute</a>.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/503701/original/file-20230109-8020-tpch1g.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="lizard clings to a vertical fence post" src="https://images.theconversation.com/files/503701/original/file-20230109-8020-tpch1g.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/503701/original/file-20230109-8020-tpch1g.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/503701/original/file-20230109-8020-tpch1g.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/503701/original/file-20230109-8020-tpch1g.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/503701/original/file-20230109-8020-tpch1g.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/503701/original/file-20230109-8020-tpch1g.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/503701/original/file-20230109-8020-tpch1g.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A male fence lizard showing off his throat and abdominal badges.</span>
<span class="attribution"><span class="source">Tracy Langkilde</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Such interactions are now common in the southeastern United States, where native animals such as eastern fence lizards (<em>Sceloporus undulatus</em>) have <a href="https://doi.org/10.1890/08-0355.1">shared their habitat</a> with the invasive red imported fire ant (<em>Solenopsis invicta</em>) for decades.</p>
<p><a href="https://scholar.google.com/citations?user=4fYdo1MAAAAJ&hl=en&oi=ao">Our</a> <a href="https://scholar.google.com/citations?user=4vr-wR8AAAAJ&hl=en&oi=ao">research</a> <a href="http://langkildelab.com">group</a> has been studying the interactions between these two species and how they change over time. These small lizards, about 6 inches (15 centimeters) from nose to the tip of the tail, have been native to the southeastern United States <a href="https://doi.org/10.2307/1562904">for thousands of years</a>. Invasive red imported fire ants are originally from South America but were unintentionally introduced to the port of Mobile, Alabama, in the 1930s and have steadily spread northward – into the lizards’ territory – since their introduction.</p>
<p>We’re particularly interested in how animals may adapt to coexist with venomous species. The fire ants’ well-documented path of invasion, and the fact that they are currently restricted to just a portion of the lizards’ range, allows us to compare how lizards from ecologically similar areas differ based on the presence or absence of these fire ants. Overall it seems the lizards are learning to live with the invaders, adapting their behavior and bodies to better survive attacks from the ants and using them as a new food source.</p>
<h2>Changing looks and behavior to survive attacks</h2>
<p>Lizards and fire ants require a similar habitat to survive – open and often disturbed patches of land that let in sunlight. We’ve found that lizards <a href="https://doi.org/10.1139/Z09-053">don’t avoid areas</a> where fire ants are and they don’t avoid their scent. It would be difficult to do, anyway, given how ubiquitous these ants are – within the areas they’ve invaded, fire ant mounds can dot the landscape every few meters.</p>
<p>Foraging fire ants can locate a basking lizard within minutes and quickly <a href="https://doi.org/10.1093/beheco/ars011">recruit other ants</a> to attack. All is not lost for the lizard, however. Some do what you probably would when attacked by fire ants: flick them off and move away. This twitch-and-flee behavior <a href="https://doi.org/10.1093/beheco/ars011">removes scout ants</a>, preventing them from recruiting reinforcements, and also gets rid of any other ant attackers.</p>
<p>This behavior is common in baby fence lizards, which are vulnerable even to native ants, but is usually lost in adults as they outgrow threats from native ants by getting larger. However, in areas with fire ants, <a href="https://doi.org/10.1890/08-0355.1">adult lizards retain this behavior</a> that <a href="https://doi.org/10.1111/gcb.14510">better enables them to</a> <a href="https://doi.org/10.1093/beheco/ars011">survive fire ant attack</a>.</p>
<p>Lizards can’t tell whether they have a potentially deadly fire ant crawling on them or if it’s something harmless like a fly. So, to be safe, they respond in the same way to anything that they <a href="https://doi.org/10.1016/j.anbehav.2016.11.006">feel climbing on their scales</a>. Unfortunately, this shake-it-off behavior doesn’t solve all the lizards’ problems, since it breaks their usual camouflage, making them more obvious to visual predators like birds. We have observed <a href="https://doi.org/10.1016/j.anbehav.2016.11.006">more evidence of wounds</a> in fire ant-adapted lizards. And a lizard that survives a fire ant attack can still <a href="https://doi.org/10.1071/WR10098">die weeks to months later</a>, though we’re not sure yet why.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/503698/original/file-20230109-9349-lxdmaf.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="fingers hold a transparent ruler up to a lizard's extended rear leg" src="https://images.theconversation.com/files/503698/original/file-20230109-9349-lxdmaf.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/503698/original/file-20230109-9349-lxdmaf.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/503698/original/file-20230109-9349-lxdmaf.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/503698/original/file-20230109-9349-lxdmaf.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/503698/original/file-20230109-9349-lxdmaf.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/503698/original/file-20230109-9349-lxdmaf.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/503698/original/file-20230109-9349-lxdmaf.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Careful measurements in the field find longer legs in lizard populations exposed to fire ants.</span>
<span class="attribution"><span class="source">Nisha Ligon</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>We find lizard populations that have been living with fire ants have adapted <a href="https://doi.org/10.1670/11-002">to have longer legs</a>, <a href="https://doi.org/10.1111/gcb.14510">which are better at removing fire ants</a> when a lizard twitches and flees. This is a big shift for this species, reversing the <a href="https://doi.org/10.1111/gcb.14510">latitudinal pattern</a> we see in museum specimens – lizards tend to have shorter limbs the closer the population is to the equator. Since limb length can have important implications for how animals move around their environment, this anatomical change could have <a href="https://doi.org/10.1016/S1095-6433(01)00469-X">important consequences</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/503700/original/file-20230109-9211-auh4va.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="front half of a lizard with part of an ant's body coming out of its mouth" src="https://images.theconversation.com/files/503700/original/file-20230109-9211-auh4va.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/503700/original/file-20230109-9211-auh4va.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=424&fit=crop&dpr=1 600w, https://images.theconversation.com/files/503700/original/file-20230109-9211-auh4va.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=424&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/503700/original/file-20230109-9211-auh4va.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=424&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/503700/original/file-20230109-9211-auh4va.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=533&fit=crop&dpr=1 754w, https://images.theconversation.com/files/503700/original/file-20230109-9211-auh4va.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=533&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/503700/original/file-20230109-9211-auh4va.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=533&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Potentially dangerous venomous stings don’t stop these lizards from learning to make a meal of the invasive fire ants.</span>
<span class="attribution"><span class="source">Tracy Langkilde and Travis Robbins</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Venomous predator can also be prey</h2>
<p>These lizards, especially when they are young, eat a lot of ants of various types. Eating a fire ant, though, can mean getting stung inside the mouth, which can make this a <a href="https://doi.org/10.1002/jez.570">lethal meal</a>. Baby lizards quickly learn to avoid eating fire ants, but this leads to their also <a href="https://doi.org/10.1007/s10530-019-01949-3">avoiding their native ant diet</a>, the consequences of which are unknown.</p>
<p>Adult lizards, on the other hand, are less vulnerable to succumbing to consumed fire ants and take advantage of this <a href="https://doi.org/10.1007/s00442-016-3596-3">new</a> <a href="https://doi.org/10.1007/s10530-012-0295-9">food</a> <a href="https://doi.org/10.1111/j.1420-9101.2012.02583.x">source</a>. So there’s an upside to these troublesome insect invaders for fence lizards.</p>
<h2>Physiological changes triggered by fire ants</h2>
<p>Lethal outcomes are the most striking consequence of interactions between fire ants and fence lizards, but that’s not the full story.</p>
<p>As you might imagine – or even have experienced – being stung by fire ants is stressful for lizards, as indicated by an <a href="https://doi.org/10.1086/689983">increase in a stress-relevant glucocorticoid hormone</a> following attack, just as you would experience after getting a scare.</p>
<p>We find that lizards that frequently experience fire ant attacks have a different “stress profile.” They have <a href="https://doi.org/10.1111/gcb.14510">higher</a> <a href="https://doi.org/10.1016/j.ygcen.2011.12.027">concentrations</a> of this stress hormone even while at rest. They show <a href="https://doi.org/10.1016/j.yhbeh.2016.11.010">greater</a> <a href="https://doi.org/10.1016/j.ygcen.2011.12.027">increases</a> in glucocorticoids in response to a stressor and have <a href="https://doi.org/10.1093/beheco/arab099">different</a> <a href="https://doi.org/10.1016/j.yhbeh.2011.04.001">behavioral</a> and <a href="https://doi.org/10.1093/biolinnean/blz154">immune</a> <a href="https://doi.org/10.1242/jeb.188359">responses</a> to glucocorticoid exposure. While stress gets a bad rap, these hormones play an important role and in this case can trigger survival-enhancing <a href="https://doi.org/10.1890/08-0355.1">behavioral</a> <a href="https://doi.org/10.1093/beheco/ars011">responses</a> to <a href="https://doi.org/10.1016/j.anbehav.2009.10.028">fire</a> <a href="https://doi.org/10.1111/gcb.14510">ants</a>.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/ekfdDEivgAI?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Eating fire ants is almost like getting a vaccine against their stings for lizards.</span></figcaption>
</figure>
<p>Lizards living with fire ants show <a href="https://doi.org/10.1002/jez.2418">changes to their immune systems</a>. They have elevated levels of IgM antibodies that respond to fire ants and higher levels of a type of white blood cell that can help <a href="https://doi.org/10.1016/j.alit.2015.09.002">neutralize venom toxins</a>. They also have decreased levels of other immune system components. Together, these immune differences may allow lizards to better coexist with fire ants, with the elevated immune measures being particularly useful when dealing with stings. Tailoring the immune system to survive fire ant attacks may, however, leave lizards more vulnerable to other immune challenges, such as viruses.</p>
<p>Getting stung over a period of time stimulates lizards’ skin immunity, which could guard against effects of skin damage. Additionally, feeding on fire ants that we’ve rendered in the lab incapable of stinging <a href="https://doi.org/10.1007/s10530-022-02939-8">increases some immune measures</a> in the lizards above what we see in lizards that were stung by fire ants. This bolstered immunity may then help lizards survive future stings. We think the elevated immunity we see in wild lizards in fire ant-invaded places may be caused by consumption of fire ants.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/503702/original/file-20230109-6779-g7lf20.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="lizard missing a front foot" src="https://images.theconversation.com/files/503702/original/file-20230109-6779-g7lf20.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/503702/original/file-20230109-6779-g7lf20.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=376&fit=crop&dpr=1 600w, https://images.theconversation.com/files/503702/original/file-20230109-6779-g7lf20.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=376&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/503702/original/file-20230109-6779-g7lf20.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=376&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/503702/original/file-20230109-6779-g7lf20.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=472&fit=crop&dpr=1 754w, https://images.theconversation.com/files/503702/original/file-20230109-6779-g7lf20.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=472&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/503702/original/file-20230109-6779-g7lf20.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=472&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Injuries like this one to a forelimb appear to be more common in lizard populations that have adapted to the fire ants.</span>
<span class="attribution"><span class="source">Christopher Thawley</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Animals adapt – but there can be consequences</h2>
<p>The effects of invasive fire ant and eastern fence lizard interactions demonstrate how species can adapt to survive the presence of invasive predators. Behavioral shifts can allow animals to avoid or escape attack, and changes in morphology can make these strategies more effective. And eating venomous prey may provide immune protection against subsequent attack.</p>
<p>However, this research also illustrates that adaptations are not a panacea. While adapting to a changing world is clearly critical for survival, by its very nature this changes animals, pushing them off their original evolutionary trajectory and leaving them vulnerable to new threats. Getting a full picture of the consequences of the presence of a new threatening species, and of the changes that animals may need to make to survive them, is critical if scientists are going to be able to predict and manage the impact of invasive species on native communities.</p><img src="https://counter.theconversation.com/content/186275/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Funding was provided in part by the National Science Foundation.</span></em></p><p class="fine-print"><em><span>Tracy Langkilde receives funding from The Pennsylvania State University. </span></em></p>The ways eastern fence lizards have changed in response to red imported fire ants demonstrate how species can adapt to survive the presence of invasive predators.Catherine Tylan, Postdoctoral Researcher in Biology, Penn StateTracy Langkilde, Professor of Biology and Verne M. Willaman Dean, Eberly College of Science, Penn StateLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1906062022-09-20T03:19:34Z2022-09-20T03:19:34ZYoung cold-blooded animals are suffering the most as Earth heats up, research finds<figure><img src="https://images.theconversation.com/files/485445/original/file-20220920-18478-bj2hb3.jpg?ixlib=rb-1.1.0&rect=15%2C15%2C5160%2C3422&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Climate change is <a href="https://www.ipcc.ch/report/ar6/wg1/">making heatwaves</a> worse. Many people have already noticed the difference – and so too have other animals.</p>
<p>Sadly, <a href="https://onlinelibrary.wiley.com/doi/10.1111/ele.14083">research</a> by myself and colleagues has found young animals, in particular, are struggling to keep up with rising temperatures, likely making them more vulnerable to climate change than adults of their species.</p>
<p>The study focused on “ectotherms”, or cold-blooded animals, which comprise <a href="https://doi.org/10.11646/zootaxa.3148.1.2">more than 99%</a> of animals on Earth. They include fish, reptiles, amphibians and insects. The body temperature of these animals reflects outside temperatures – so they can get <a href="https://www.pnas.org/doi/abs/10.1073/pnas.1316145111">dangerously hot</a> during heat waves.</p>
<p>In a warming world, a species’ ability to adapt or acclimatise to temperatures is crucial. Our study found that young ectotherms, in particular, can struggle to handle more heat as their habitat warms up. That may have dramatic consequences for biodiversity as climate change worsens.</p>
<p>Our findings are yet more evidence of the need to urgently reduce greenhouse gas emissions to prevent catastrophic global heating. Humans must also provide and retain cool spaces to help animals navigate a warmer future.</p>
<figure class="align-center ">
<img alt="large and small beetles move across a log" src="https://images.theconversation.com/files/485449/original/file-20220920-14334-jailsk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/485449/original/file-20220920-14334-jailsk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/485449/original/file-20220920-14334-jailsk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/485449/original/file-20220920-14334-jailsk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/485449/original/file-20220920-14334-jailsk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/485449/original/file-20220920-14334-jailsk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/485449/original/file-20220920-14334-jailsk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A species’ ability to adapt or acclimatise to higher temperatures is crucial.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Tolerating heat in a changing climate</h2>
<p>The body temperature of ectotherms is extremely variable. As they move through their habitat, their body temperature varies according to the outside conditions. </p>
<p>However, there’s only so much heat these animals can tolerate. Heat tolerance is defined as the maximum body temperature ectotherms can handle before they <a href="https://doi.org/10.1139/z97-783">lose functions</a> such as the ability to walk or swim. During heat waves, their body temperature gets so high they can <a href="https://www.pnas.org/doi/abs/10.1073/pnas.1316145111">die</a>. </p>
<p>Species, <a href="https://doi.org/10.1111/geb.12911">including ectotherms</a>, can adapt to challenges in their environment over time by evolving across generations. But the rate at which global temperatures are rising means in many cases, this adaptation is not happening fast enough. That’s why we need to understand how animals acclimatise to rising temperatures within a single lifetime. </p>
<p>Unfortunately, some young animals have little to no ability to move and seek cooler temperatures. For example, baby lizards inside eggs cannot move elsewhere. And owing to their small size, juvenile ectotherms cannot move great distances.</p>
<p>This suggests young animals may be particularly vulnerable during intense heat waves. But we know <a href="https://onlinelibrary.wiley.com/doi/full/10.1002/jez.2414">very little</a> about how young animals acclimatise to high temperatures. Our research sought to find out more.</p>
<figure class="align-center ">
<img alt="snakes hatching from eggs" src="https://images.theconversation.com/files/485446/original/file-20220920-18498-ys0duh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/485446/original/file-20220920-18498-ys0duh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=407&fit=crop&dpr=1 600w, https://images.theconversation.com/files/485446/original/file-20220920-18498-ys0duh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=407&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/485446/original/file-20220920-18498-ys0duh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=407&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/485446/original/file-20220920-18498-ys0duh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=511&fit=crop&dpr=1 754w, https://images.theconversation.com/files/485446/original/file-20220920-18498-ys0duh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=511&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/485446/original/file-20220920-18498-ys0duh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=511&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Ectotherms cannot escape their eggs to avoid a heatwave.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Young animals at risk</h2>
<p><a href="https://onlinelibrary.wiley.com/doi/10.1111/ele.14083">Our study</a> drew on 60 years of research into 138 ectotherm species from around the world. </p>
<p>Overall, we found the heat tolerance of embryos and juvenile ectotherms increased very little in response to rising temperatures. For each degree of warming, the heat tolerance of young ectotherms only increased by an average 0.13°C.</p>
<p>The physiology of heat acclimatisation in animals is very complex and poorly understood. It appears linked to a number of factors such as <a href="https://doi.org/10.1016/j.scitotenv.2021.145208">metabolic activity</a> and <a href="https://doi.org/10.1007/s10695-011-9578-9">proteins</a> produced by cells in response to stress. </p>
<p>Our research showed young land-based animals were worse at acclimatising to heat than aquatic animals. This may be because moving to a cooler temperature on land is easier than in an aquatic environment, so land-based animals may not have developed the same ability to acclimatise to heat.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/thousands-of-photos-captured-by-everyday-australians-reveal-the-secrets-of-our-marine-life-as-oceans-warm-189231">Thousands of photos captured by everyday Australians reveal the secrets of our marine life as oceans warm</a>
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</em>
</p>
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<figure class="align-center ">
<img alt="Large striped fish swimming with smaller fish" src="https://images.theconversation.com/files/485448/original/file-20220920-376-ydzc7s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/485448/original/file-20220920-376-ydzc7s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/485448/original/file-20220920-376-ydzc7s.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/485448/original/file-20220920-376-ydzc7s.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/485448/original/file-20220920-376-ydzc7s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/485448/original/file-20220920-376-ydzc7s.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/485448/original/file-20220920-376-ydzc7s.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Aquatic animals appear better able to acclimatise to warmer conditions than land-based animals.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>Heat tolerance can vary within a species. It can <a href="https://royalsocietypublishing.org/doi/full/10.1098/rspb.2015.0401">depend on</a> what temperatures an animal has experienced during its lifetime and, as such, the extent to which it has acclimatised. But surprisingly, our research found past exposure to high temperatures does not necessarily help a young animal withstand future high temperatures. </p>
<p>Take, for example, Lesueur’s velvet gecko which is found mostly along Australia’s east coast. <a href="https://doi.org/10.1242/jeb.152272">Research shows</a> juveniles from eggs incubated in cooler nests (23.2°C) tolerated temperatures up to 40.2°C. In contrast, juveniles from warmer nests (27°C) only tolerated temperatures up to 38.7°C.</p>
<p>Those patterns can persist through adulthood. For example, adult male <a href="https://www.proquest.com/pagepdf/305356367">mosquito fish</a> from eggs incubated to 32°C were less tolerant to heat than adult males that experienced 26°C during incubation.</p>
<p>These results show embryos are especially vulnerable to extreme heat. Instead of getting better at handling heat, warmer eggs tend to produce juveniles and adults less capable of withstanding a warmer future.</p>
<p>Overall, our findings suggest young cold-blooded animals are already struggling to cope with rising temperatures – and conditions during early life can have lifelong consequences.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/we-know-heatwaves-kill-animals-but-new-research-shows-the-survivors-dont-get-off-scot-free-184645">We know heatwaves kill animals. But new research shows the survivors don’t get off scot-free</a>
</strong>
</em>
</p>
<hr>
<figure class="align-center ">
<img alt="baby turtles moving across sand" src="https://images.theconversation.com/files/485447/original/file-20220920-17325-deaukn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/485447/original/file-20220920-17325-deaukn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/485447/original/file-20220920-17325-deaukn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/485447/original/file-20220920-17325-deaukn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/485447/original/file-20220920-17325-deaukn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/485447/original/file-20220920-17325-deaukn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/485447/original/file-20220920-17325-deaukn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Young cold-blooded animals are already struggling to cope with higher temperatures.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>What’s next?</h2>
<p>To date, most studies on the impacts of climate change have focused on adults. Our research suggests animals may be harmed by heatwaves long before they reach adulthood – perhaps even before they’re born. </p>
<p>Alarmingly, this means we may have underestimated the damage climate change will cause to biodiversity. </p>
<p>Clearly, it’s vitally important to limit global greenhouse gas emissions to the extent required by the <a href="https://unfccc.int/process-and-meetings/the-paris-agreement/the-paris-agreement">Paris Agreement</a>. </p>
<p>But we can also act to protect species at a finer scale – by conserving habitats that allow animals to find shade and shelter during heatwaves. Such habitats include trees, shrubs, burrows, ponds, caves, logs and rocks. These places must be created, restored and preserved to help animals prosper in a warming world.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/beyond-net-zero-we-should-if-we-can-cool-the-planet-back-to-pre-industrial-levels-187781">Beyond net-zero: we should, if we can, cool the planet back to pre-industrial levels</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/190606/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Patrice Pottier works for The University of New South Wales. He is supported by a UNSW Scientia Doctoral scholarship. </span></em></p>In a warming world, a species’ ability to acclimatise to temperatures is crucial. But young ectotherms can struggle to handle the heat.Patrice Pottier, PhD Candidate in Ecology and Evolutionary Biology, UNSW SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1886802022-09-13T17:43:35Z2022-09-13T17:43:35ZInvasive reptile and amphibian species are causing billions of dollars in damages globally<figure><img src="https://images.theconversation.com/files/482138/original/file-20220831-4764-z2dv88.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Invasive alien species are a growing concern for both the environment and economy.</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Economic growth and globalization have connected the world’s most distant places. Rapid trade and transport have boosted economic growth globally, but not without consequences: many species have been introduced to new regions, far from where they evolved.</p>
<p>Alien species are those introduced by humans to regions outside their natural range. Invasive alien species are a growing concern for both the environment and economy. </p>
<p>In recent decades, alien herpetofauna — amphibians and reptiles — have increasingly gained attention on social media, with more information being circulated about the impacts these species have on native flora and fauna. </p>
<p>And yet, the number of invasive reptiles and amphibians is increasing, facilitated by the persistently high globalization of human activities. </p>
<h2>Detrimental effects</h2>
<p>Some invasive species arrive unintentionally as hitchhikers on planes, ships and cars. Others are sold intentionally as exotic pets, which then escape or are released into the wild. Of those that survive and establish, some are able to spread with severe negative impacts, giving them the title of “invasive.” </p>
<p><a href="https://doi.org/10.1016/j.scitotenv.2022.153404">These impacts can be massive</a>. Alien species are a leading cause of biodiversity loss and extinction worldwide, affecting human welfare and quality of life. </p>
<p>While alien species can also have detrimental effects on the economy, this is often complex to assess. Available information is often scattered, covers different scales or periods, recorded using variable measurements and currencies and presented in many languages. </p>
<p>The InvaCost database, <a href="https://doi.org/10.1038/s41597-020-00586-z">the most comprehensive database of the cost of alien species and a global initiative of scientists</a>, gathers this information and makes it accessible to researchers and the public.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/482402/original/file-20220901-9301-wcqbt7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="a Burmese python swimming through shallow water" src="https://images.theconversation.com/files/482402/original/file-20220901-9301-wcqbt7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/482402/original/file-20220901-9301-wcqbt7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/482402/original/file-20220901-9301-wcqbt7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/482402/original/file-20220901-9301-wcqbt7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/482402/original/file-20220901-9301-wcqbt7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/482402/original/file-20220901-9301-wcqbt7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/482402/original/file-20220901-9301-wcqbt7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The alien Burmese python has successfully established itself in the Everglades National Park in Florida, where it has decimated local mammal populations.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<h2>Surprising impacts</h2>
<p>The most common pathway for invasive reptiles and amphibians is the often-illegal trade of exotic snakes and frogs as pets. </p>
<p>Another common pathway is release for biological control, where a new species is introduced in an attempt to control a pest species. This is how <a href="https://doi.org/10.1111/j.1469-1795.2009.00319.x">the cane toad was introduced in Australia</a>. </p>
<p>Other pathways include aquaculture enterprises, such as those that raise <a href="https://doi.org/10.1007/s10530-007-9178-x">American bullfrogs for human consumption</a> and <a href="https://doi.org/10.2984/1534-6188(2007)61%5B307:BAIOPI%5D2.0.CO;2">species hitchhiking on planes or boats</a>.</p>
<p>Alien reptiles and amphibians can have quite unusual and surprising economic impacts. For instance, after the arrival of the coquí frog to Hawaii via contaminated nursery plants, <a href="https://ageconsearch.umn.edu/record/21313/">its very loud mating song caused severe declines in property values in infested areas</a>.</p>
<p>More typical economic impacts stem from programs for the control or eradication of these species. Management programs are needed due to the damage these invaders cause on biodiversity by eliminating native species, including at-risk amphibians and reptiles.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/481903/original/file-20220830-37919-2ltj1a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An American bullfrog with a large goldfish of approximately equal size in its mouth" src="https://images.theconversation.com/files/481903/original/file-20220830-37919-2ltj1a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/481903/original/file-20220830-37919-2ltj1a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=451&fit=crop&dpr=1 600w, https://images.theconversation.com/files/481903/original/file-20220830-37919-2ltj1a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=451&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/481903/original/file-20220830-37919-2ltj1a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=451&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/481903/original/file-20220830-37919-2ltj1a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/481903/original/file-20220830-37919-2ltj1a.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/481903/original/file-20220830-37919-2ltj1a.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">American bullfrogs have the largest reported economic impacts of any amphibian.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Bullfrog_tries_to_swallow_huge_Goldfish_-_Fish_survived.jpg">(Rusty Clark/Wikimedia Commons)</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>This is the case for one of the most famous snakes in the pet trade, the California kingsnake, <a href="https://phys.org/news/2021-12-invasive-snake-gran-canaria-native.html">for which numerous eradication programs on the Canary Islands exist</a>.</p>
<h2>Quantifying the damage</h2>
<p>Our team of researchers quantified and synthesized, for the first time, <a href="https://doi.org/10.1038/s41598-022-15079-9">the economic costs of invasive reptiles and amphibians worldwide using the InvaCost database</a>. Between 1986 and 2020, we found that the cost of invasive reptiles and amphibians was massive, totalling approximately US$17 billion — with US$10.4 billion due to reptiles and US$6.3 billion due to amphibians. </p>
<p>Further, the bulk of these costs was from a small subset of highly impactful species. Most notably, the brown tree snake alone has resulted in a loss of US$4.5 million per year in Guam due to island-wide power outages and costing a total of US$10.34 billion during the study period (1986-2019).</p>
<p>The runner-up in terms of total impacts was the American bullfrog, whose impacts of US$6.04 billion accounted for approximately 97 per cent of the total amphibian cost, mostly due to control and eradication measures in Europe.</p>
<p>The types of costs incurred varied across species. In the case of amphibians, costs mostly originated from government expenditures — US$6.25 billion, or 99.6 per cent. These costs are derived from mitigating the spread or impacts of invaders through prevention, control, research, long-term management or eradication. </p>
<p>Reptile costs, however, mostly affected the public and social welfare sector, reportedly causing staggering damages — US$10.02 billion, or 96.6 per cent. These costs are incurred directly due to the impact of invaders, such as yield loss, infrastructure damage or income reduction.</p>
<p>Geographically, we found that economic impacts were present across all continents, except for amphibians in Africa, likely due to the lack of information. The geographic regions most affected were Europe by amphibians (US$6.04 billion), and Oceania and the Pacific Islands by reptiles (US$10.35 billion, 99.61 per cent).</p>
<p><div data-react-class="InstagramEmbed" data-react-props="{"url":"https://www.instagram.com/p/BsR3Q1XgUjH","accessToken":"127105130696839|b4b75090c9688d81dfd245afe6052f20"}"></div></p>
<h2>Prevention is the better solution</h2>
<p>The economic costs of herpetofauna invasions are massive across all continents, but also underestimated. The vast part of our estimated total cost originated from only two species: the brown tree snake and the American bullfrog, which is likely, at least in part, due to missing data. </p>
<p>Further, only 21 species (six amphibians and 15 reptiles) were reported in InvaCost, out of 280 alien amphibians and reptiles recorded worldwide. </p>
<p>It should nevertheless be acknowledged that not all invasive reptiles and amphibians will have tangible monetary impacts, so some gaps are expected. Nonetheless, a greater research effort is needed to distinguish the true absence of economic cost from gaps in cost detection — especially for those species known to cause detrimental ecological impacts.</p>
<p>And as shown, investments in preventive measures can be <a href="https://doi.org/10.1016/j.scitotenv.2022.153404">an important money-saving measure for the public over the long term</a>, compared to reactive control approaches once a species has successfully invaded. </p>
<p>We propose the compilation of national lists for species facing import and selling bans, better screening for potentially harmful species and a more comprehensive effort to obtain information on the actual and species-specific costs. Our research highlights the importance of these measures to prevent future immense economic costs.</p><img src="https://counter.theconversation.com/content/188680/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>EJH was funded by a B3X postdoctoral fellowship from the Fonds de Recherche du Québec - Nature et Technologies.</span></em></p><p class="fine-print"><em><span>Ismael Soto Almena does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>New research has found that since the mid-1980s, the economic impact of invasive reptiles and amphibians totals more than US$17 billion.Ismael Soto Almena, PhD Student, Protection of Waters, University of South BohemiaEmma J. Hudgins, Postdoctoral fellow, Biology, Carleton UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1824272022-05-11T19:55:02Z2022-05-11T19:55:02ZTug of war between survival and reproductive fitness: how chameleons become brighter without predators around<figure><img src="https://images.theconversation.com/files/462190/original/file-20220510-22-8t3is2.jpg?ixlib=rb-1.1.0&rect=56%2C0%2C2471%2C921&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Martin Whiting</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Invasive species offer a rare research opportunity, as they often colonise new environments very different to their native habitat. One such species is the Jackson’s three-horned chameleon (<em>Triocerus j. xantholophus</em>), which was accidentally introduced to the Hawaiian Islands in the 1970s. </p>
<p>Our study, <a href="https://doi.org/10.1126/sciadv.abn2415">published today</a> in Science Advances, shows Hawaiian chameleons display much brighter social signals than individuals from their native habitat range in East Africa – and could represent an example of rapid evolution. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/461690/original/file-20220506-26-f6phtq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/461690/original/file-20220506-26-f6phtq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/461690/original/file-20220506-26-f6phtq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=569&fit=crop&dpr=1 600w, https://images.theconversation.com/files/461690/original/file-20220506-26-f6phtq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=569&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/461690/original/file-20220506-26-f6phtq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=569&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/461690/original/file-20220506-26-f6phtq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=715&fit=crop&dpr=1 754w, https://images.theconversation.com/files/461690/original/file-20220506-26-f6phtq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=715&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/461690/original/file-20220506-26-f6phtq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=715&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A male Jackson’s three-horned chameleon (above) courting a female (below) in Kenya.</span>
<span class="attribution"><span class="source">Martin Whiting.</span></span>
</figcaption>
</figure>
<h2>A long way from home</h2>
<p>In 1972, about 36 Jackson’s chameleons made their way from their native Kenya to the Hawaiian island of Oahu, destined for the pet trade.</p>
<p>The chameleons were a little worse for wear by the time they arrived in Hawaii, following a long and taxing journey that would have begun days before they were loaded onto the plane in Nairobi.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/461687/original/file-20220506-22-ipiyi3.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/461687/original/file-20220506-22-ipiyi3.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/461687/original/file-20220506-22-ipiyi3.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=367&fit=crop&dpr=1 600w, https://images.theconversation.com/files/461687/original/file-20220506-22-ipiyi3.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=367&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/461687/original/file-20220506-22-ipiyi3.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=367&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/461687/original/file-20220506-22-ipiyi3.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=462&fit=crop&dpr=1 754w, https://images.theconversation.com/files/461687/original/file-20220506-22-ipiyi3.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=462&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/461687/original/file-20220506-22-ipiyi3.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=462&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Invasive chameleons have made it to the Hawaiian islands – the world’s most isolated island archipelago.</span>
<span class="attribution"><span class="source">Wikimedia Commons</span></span>
</figcaption>
</figure>
<p><a href="https://chicagoherp.org/wp-content/uploads/bsk-pdf-manager/2019/12/263.pdf">The story goes</a> that an Oahu pet shop owner, Robin Ventura, opened the crate in his garden to give them fresh air and an opportunity to recover. Presumably, he underestimated the speed with which chameleons can move (and recover) – and they quickly dispersed into the surrounding area.</p>
<p>This founding population represented an accidental invasion, and subsequently became an unplanned experiment in evolution. What happens when an animal with colourful social displays – from a population with lots of bird and snake predators – is introduced to an island virtually free of predators? </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-do-chameleons-and-other-creatures-change-colour-13842">How do chameleons and other creatures change colour?</a>
</strong>
</em>
</p>
<hr>
<h2>Evolution in action?</h2>
<p>We predicted Hawaiian chameleons, as a result of being relatively free from predation, would have more elaborate or brighter displays than their Kenyan counterparts. We also predicted they would be more conspicuous when viewed by their East African predators, such as birds and snakes.</p>
<p>In the animal kingdom, bright or colourful displays can attract the attention of sharp-eyed predators. This reduces an individual animal’s likelihood of survival and, by extension, its reproductive fitness (or the number of genes it passes on to future generations). </p>
<p>When survival is threatened, <a href="https://en.wikipedia.org/wiki/Natural_selection">natural selection</a> acts as a brake and halts the further elaboration of colour, or shifts bright colours to areas of the body less visible to predators. </p>
<p>For instance, many lizard species have bright colours concealed on their undersides or throats. In South Africa, male Augrabies flat lizards will signal to rival males by raising their underside and exposing the throat, which is puffed out.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/461692/original/file-20220506-1367-w6uifv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/461692/original/file-20220506-1367-w6uifv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/461692/original/file-20220506-1367-w6uifv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=447&fit=crop&dpr=1 600w, https://images.theconversation.com/files/461692/original/file-20220506-1367-w6uifv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=447&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/461692/original/file-20220506-1367-w6uifv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=447&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/461692/original/file-20220506-1367-w6uifv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=562&fit=crop&dpr=1 754w, https://images.theconversation.com/files/461692/original/file-20220506-1367-w6uifv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=562&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/461692/original/file-20220506-1367-w6uifv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=562&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Many lizard species, such as this Augrabies flat lizard, have bright colours on body parts that are less visible to predators such as birds.</span>
<span class="attribution"><span class="source">Martin Whiting</span></span>
</figcaption>
</figure>
<p>On the other hand, conspicuous displays may also increase fitness. For example, brighter or more colourful males may gain greater access to females, either by winning contests with rival males, or simply appearing more attractive to females.</p>
<p>This tug of war between survival and fitness is well documented in species with fixed or seasonally dependent colouration. For instance, <a href="https://theguppyproject.weebly.com/">guppies</a> become less colourful when dangerous predators share their streams. However, it’s less understood in animals with dynamic colour change such as chameleons. </p>
<p>Although we have a good understanding of <a href="https://theconversation.com/how-do-chameleons-and-other-creatures-change-colour-13842">how chameleons change colour</a>, we don’t know if they modulate their displays when there are more predators in their environment. It may also be that natural selection prevents them from producing colour signals that are colourful or bright beyond a certain threshold.</p>
<p>To test our predictions, we travelled to Kenya and Hawaii to study colour change in wild chameleons.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/-G2WYnb265I?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">In rivalling male chameleons, dominance is signalled by turning from green to lemon-yellow. In this clip, two males are evenly matched and both signal their dominance. When the contest is settled, the winner remains lemon-yellow a while longer while the subordinate turns brown.</span></figcaption>
</figure>
<h2>Vibrant test subjects</h2>
<p>Chameleons are great study subjects because they have a very strong stimulus response. You can pop them on a branch away from their usual haunts and present them with a fake predator or another chameleon, and they will devote all their attention to the stimulus while completely ignoring you!</p>
<p>We presented each male chameleon with a rival male, a female, a model bird predator and a model snake predator - each in a one-on-one interaction. During the presentations we measured their colour using an optic spectrometer. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/461693/original/file-20220506-1371-szia9x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/461693/original/file-20220506-1371-szia9x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/461693/original/file-20220506-1371-szia9x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=319&fit=crop&dpr=1 600w, https://images.theconversation.com/files/461693/original/file-20220506-1371-szia9x.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=319&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/461693/original/file-20220506-1371-szia9x.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=319&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/461693/original/file-20220506-1371-szia9x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=401&fit=crop&dpr=1 754w, https://images.theconversation.com/files/461693/original/file-20220506-1371-szia9x.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=401&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/461693/original/file-20220506-1371-szia9x.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=401&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Chameleons were exposed to a model snake (pictured: African boomslang) and bird (pictured: African cuckoo-hawk) predators.</span>
<span class="attribution"><span class="source">Martin Whiting</span></span>
</figcaption>
</figure>
<p>This instrument allows us to quantify two metrics of colour: chromatic contrast (essentially how colourful they are) and luminance contrast (how bright they are). We could then estimate how detectable a displaying chameleon would be to an observer – be it another chameleon, or a bird or snake predator.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/461696/original/file-20220506-18-isgb96.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/461696/original/file-20220506-18-isgb96.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/461696/original/file-20220506-18-isgb96.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=362&fit=crop&dpr=1 600w, https://images.theconversation.com/files/461696/original/file-20220506-18-isgb96.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=362&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/461696/original/file-20220506-18-isgb96.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=362&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/461696/original/file-20220506-18-isgb96.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=455&fit=crop&dpr=1 754w, https://images.theconversation.com/files/461696/original/file-20220506-18-isgb96.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=455&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/461696/original/file-20220506-18-isgb96.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=455&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Chameleons lock horns during fights for dominance.</span>
<span class="attribution"><span class="source">Devi Stuart-Fox</span></span>
</figcaption>
</figure>
<p>We also measured the leafy vegetation that forms the backdrop against which a chameleon signals. This way we could estimate how detectable a displaying chameleon would be against a particular background. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/461697/original/file-20220506-1367-gl64c3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/461697/original/file-20220506-1367-gl64c3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/461697/original/file-20220506-1367-gl64c3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/461697/original/file-20220506-1367-gl64c3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/461697/original/file-20220506-1367-gl64c3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/461697/original/file-20220506-1367-gl64c3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/461697/original/file-20220506-1367-gl64c3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/461697/original/file-20220506-1367-gl64c3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A male Jackson’s three-horned chameleon from Hawaii, showing subordinate colours.</span>
<span class="attribution"><span class="source">Martin Whiting</span></span>
</figcaption>
</figure>
<h2>An exciting example of rapid change</h2>
<p>The results were particularly exciting and exceeded our expectations. We found Hawaiian chameleons had much brighter displays than Kenyan chameleons during male contests and when courting females. They were also more conspicuous against their Hawaiian background than a Kenyan background. </p>
<p>This is consistent with what scientists term “local adaptation”. This is the idea that signals will be fine-tuned to be more detectable in the environment in which they are used. </p>
<p>For Hawaiian chameleons, one unintended consequence of being brighter was they were also more detectable to their native predators.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/461691/original/file-20220506-21-fxggne.png?ixlib=rb-1.1.0&rect=70%2C542%2C2279%2C2257&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/461691/original/file-20220506-21-fxggne.png?ixlib=rb-1.1.0&rect=70%2C542%2C2279%2C2257&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/461691/original/file-20220506-21-fxggne.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/461691/original/file-20220506-21-fxggne.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/461691/original/file-20220506-21-fxggne.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/461691/original/file-20220506-21-fxggne.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/461691/original/file-20220506-21-fxggne.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/461691/original/file-20220506-21-fxggne.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A male Jackson’s three-horned chameleon living wild on Oahu, Hawaii.</span>
<span class="attribution"><span class="source">Brenden S. Holland</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Interestingly, this effect was more pronounced when facing birds compared to snakes – probably because snakes have poorer colour discrimination than birds. Finally, Hawaiian chameleons also had a greater capacity to change colour than Kenyan chameleons - they could do so over a greater range.</p>
<p>We can’t be completely sure brighter signals in Hawaiian chameleons represents rapid evolution. It’s also possible this degree of colour change is due to <a href="https://en.wikipedia.org/wiki/Phenotypic_plasticity">plasticity</a>, which is when an animal changes to a different state due to prevailing environmental conditions. </p>
<p>Nevertheless, plasticity itself can evolve – and colour change in chameleons may be a combination of both evolutionary change and plasticity. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/461698/original/file-20220506-21738-2511zc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/461698/original/file-20220506-21738-2511zc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/461698/original/file-20220506-21738-2511zc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=271&fit=crop&dpr=1 600w, https://images.theconversation.com/files/461698/original/file-20220506-21738-2511zc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=271&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/461698/original/file-20220506-21738-2511zc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=271&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/461698/original/file-20220506-21738-2511zc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=340&fit=crop&dpr=1 754w, https://images.theconversation.com/files/461698/original/file-20220506-21738-2511zc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=340&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/461698/original/file-20220506-21738-2511zc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=340&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A male Jackson’s three-horned chameleon from Kenya in full display colour.</span>
<span class="attribution"><span class="source">Martin Whiting</span></span>
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</figure><img src="https://counter.theconversation.com/content/182427/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Martin Whiting works for Macquarie University. He receives funding from the Australian Research Council.</span></em></p>Researchers wanted to understand what happens when chameleons – animals that display dynamic colour change – find themselves in an environment without their natural predators.Martin Whiting, Professor of Animal Behaviour, Macquarie UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1715682021-11-18T14:06:23Z2021-11-18T14:06:23ZA fossil of a snake-like lizard has generated controversy beyond its identity<figure><img src="https://images.theconversation.com/files/432215/original/file-20211116-13-uqcclg.jpeg?ixlib=rb-1.1.0&rect=2%2C6%2C1503%2C1246&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">With four tiny legs and an extraordinarily long body, a fossil of the snake-like lizard Tetrapodophis amplectus has created controversy.</span> <span class="attribution"><span class="source">(Julius Csotonyi)</span>, <span class="license">Author provided</span></span></figcaption></figure><iframe style="width: 100%; height: 175px; border: none; position: relative; z-index: 1;" allowtransparency="" src="https://narrations.ad-auris.com/widget/the-conversation-canada/a-fossil-of-a-snake-like-lizard-has-generated-controversy-beyond-its-identity" width="100%" height="400"></iframe>
<p>More than 120 million years ago in what is now modern Brazil, <a href="https://doi.org/10.1016/j.earscirev.2021.103573">an ancient waterway was filled with all manner of strange creatures</a>. These included dinosaurs, pterosaurs, sharks, bony fishes, a dizzying array of insects, strange plants and an oddly long and small lizard: <em>Tetrapodophis amplectus</em>.</p>
<p>In 2015, the journal <em>Science</em> published a paper claiming that this <a href="https://doi.org/10.1126/science.aaa9208">elongate lizard was a snake with four legs</a>. The discovery of such a specimen could tell us a great deal about the pattern and process of snake evolution — if it was indeed a snake.</p>
<h2>Lizard, not snake</h2>
<p>Extraordinary claims attract extraordinary attention, and this means such claims require reanalysis — and possibly refutation or corroboration. In scientific research, the data must fit the hypothesis, and if it does not, then the hypothesis is rejected.</p>
<p>In late 2015, two members of our research team travelled to Solnhofen, Germany, to study the specimen and conduct firsthand observation of the anatomy of the fossil. After all, the preserved anatomy is the data upon which all subsequent hypotheses are based.</p>
<p>The results of our team’s <a href="http://dx.doi.org/10.1080/14772019.2021.1983044">detailed anatomical restudy of <em>Tetrapodophis</em> refute the hypothesis that it is a snake</a>. We also challenged the claims in the original article that it possessed both a wide gape for eating large prey and the ability to coil its body and constrict its prey. </p>
<p>Using these corrected data, our analyses of evolutionary relationships found <em>Tetrapodophis</em> to be a dolichosaur, not a snake. Dolichosaurs are an extinct group of elongated, limb-reduced lizards related to mosasaurs. Both are thought to be close relatives of snakes. It is therefore not surprising that there are some anatomical similarities between <em>Tetrapodophis</em> and snakes.</p>
<h2>It’s all in the bones</h2>
<p>Many fossils are found by splitting open a slab of rock using a hammer and chisel. The fossil of <em>Tetrapodophis</em> was found this way and is now on two slabs of rock. </p>
<p>The skull slab includes impressions of the skeleton, while the second slab preserves the natural mould of the skull and most of the remaining skeleton. The preserved skull bones are shattered into tiny bits and the ones that remain intact are from the left side of the skull. Only the front part of the left lower jaw is relatively well-preserved and it is similar to that of a dolichosaur, not a snake.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/431351/original/file-20211110-27-fnljtr.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="The skull of the snake-like lizard, mostly the bones of the left side of the head, and the natural mould of the right side of the head" src="https://images.theconversation.com/files/431351/original/file-20211110-27-fnljtr.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/431351/original/file-20211110-27-fnljtr.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=535&fit=crop&dpr=1 600w, https://images.theconversation.com/files/431351/original/file-20211110-27-fnljtr.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=535&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/431351/original/file-20211110-27-fnljtr.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=535&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/431351/original/file-20211110-27-fnljtr.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=673&fit=crop&dpr=1 754w, https://images.theconversation.com/files/431351/original/file-20211110-27-fnljtr.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=673&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/431351/original/file-20211110-27-fnljtr.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=673&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The fossil’s skull provided the most revealing clues about the creature’s identity.</span>
<span class="attribution"><span class="source">(Michael Caldwell)</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The bones of the right side of the skull are gone, but their impressions are preserved on the other slab and were not described in the <a href="https://doi.org/10.1126/science.aaa9208">first article detailing the find</a>. The bones behind the eye that form a barrier for the jaw closing muscles are complete in <em>Tetrapodophis</em>. But they are absent in all fossil and living snakes. </p>
<p>The quadrate bone, which suspends the lower jaw from the skull in lizards, is also preserved. In <em>Tetrapodophis</em> it is identical to that of a dolichosaur and other mosasaurians, not as in snakes.</p>
<p>Limb reduction and loss are not unique to snakes. Numerous living lizards — for example, skinks, anguids and pygopodid geckos — are legless or limb-reduced. They all evolved leglessness independent of each other — <a href="https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/convergent-evolution">known as convergent evolution</a> — but retained the skull features of their respective lizard kind. The same is true for snakes.</p>
<h2>A bizarre little lizard</h2>
<p><em>Tetrapodophis</em> is an amazing and bizarre little lizard even without being interpreted as a four-legged snake. It is very small, yet the body skeleton, from the back of the skull to the tip of the tail, is exceptionally elongated. Unlike any other lizard with limbs, <em>Tetrapodophis</em> has about 148 vertebrae between the front legs and the hips. Also, its tail is very long and has an additional 112 vertebrae.</p>
<p>No other lizard with four legs shows this anatomy, and it is not seen or predicted in snakes either. The body is flattened from side to side, which would have helped it swim in the water. The limbs are tiny, with the front legs being almost vestigial, and most of the wrist and ankle elements are not ossified. Clearly, it could not walk on land using its limbs. Nor could it dig or grasp any prey as <a href="https://doi.org/10.1126/science.aaa9208">originally argued</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/431341/original/file-20211110-27-7eqmtl.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A photograph of two sides of the fossil of a snake-like lizard" src="https://images.theconversation.com/files/431341/original/file-20211110-27-7eqmtl.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/431341/original/file-20211110-27-7eqmtl.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=567&fit=crop&dpr=1 600w, https://images.theconversation.com/files/431341/original/file-20211110-27-7eqmtl.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=567&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/431341/original/file-20211110-27-7eqmtl.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=567&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/431341/original/file-20211110-27-7eqmtl.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=713&fit=crop&dpr=1 754w, https://images.theconversation.com/files/431341/original/file-20211110-27-7eqmtl.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=713&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/431341/original/file-20211110-27-7eqmtl.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=713&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Part and counterpart specimens of Tetrapodophis amplectus.</span>
<span class="attribution"><span class="source">(Michael Caldwell)</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Fossils and belonging</h2>
<p>Scientific research is not independent from <a href="https://ecoevocommunity.nature.com/posts/40344-science-and-politics-why-science-should-be-a-central-piece-of-policy-making">social, political and economic contexts</a>. Scientific specimens — in paleontology, genetics, archeology or any other field — have a provenance and are intimately linked to people, culture, countries and laws.</p>
<p>Scientific specimens are governed by legislation that outlines how they can be collected and used. This includes countries that in the past suffered from “parachute science” <a href="https://www.natureindex.com/news-blog/parachute-science-falls-to-earth">where specimens were removed, legally or illegally, and local scientists were excluded from participating in the research</a>. This practice is now widely condemned as scientists <a href="https://doi.org/10.1038/s41559-021-01588-9">collectively work to decolonize science</a>.</p>
<p>Unfortunately, <em>Tetrapodophis</em> is embroiled in such legal and ethical issues. Since 1942, the law in Brazil has been clear: <a href="http://www.planalto.gov.br/ccivil_03/decreto-lei/1937-1946/Del4146.htm">no fossils can be privately owned</a>. And since 1990, <a href="http://www.planalto.gov.br/ccivil_03/decreto/1990-1994/d98830.htm">international researchers may only collect in Brazil in partnership with local institutions</a>. The type specimen — the specimen used as a reference point — of any new species must also remain in Brazil. </p>
<p>These legal requirements have been <a href="https://doi.org/10.1126/science.aac8899">ignored and publicly mocked</a> by one of the authors of the 2015 study. </p>
<p>As of November 2021, the specimen of <em>Tetrapodophis</em> remains in Germany in a private collection, on loan to a private museum: the <a href="https://www.museum-solnhofen.de/startseite-museum">Bürgermeister-Müller Museum Solnhofen</a>. Its passage from Brazil to that private German collection is unknown.</p>
<h2>Ethical matters</h2>
<p>The scientific study of privately owned fossil specimens also runs afoul of ethics policies, such those of the <a href="https://vertpaleo.org/governance-documents/">Society of Vertebrate Paleontology</a>. If science is based on the ability to test and retest ideas by re-examining data, then the specimens must always be openly available for study. The concern in paleontology is that private owners of specimens can block that freedom of access and thus unethically limit the science.</p>
<p><em>Tetrapodophis</em> is proof of this problem. Because of damage to the specimen in 2016 by another <a href="https://www.doi.org/10.1126/science.aal0327">research team</a>, and contrary to <a href="https://www.doi.org/10.1126/science.aac8899">claims that the specimen would be publicly accessible</a>, the owner blocked access to the specimen. </p>
<p>Some scientists have pronounced that this means <em>Tetrapodophis</em> is dead to science.</p>
<p>We disagree with this conclusion. Despite the controversies, the original paper has not been retracted by <em>Science</em>, and there are also thousands of published references to “<em>Tetrapodophis</em> the four-legged snake.”</p>
<p>We completed our re-examination of the specimen in an effort to correct the record and describe this bizarre fossil lizard for what it is. We also hope that by doing so, we will have reignited the discussion around the specimen with the goal of repatriating it to Brazil.</p><img src="https://counter.theconversation.com/content/171568/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michael Caldwell receives funding from the Natural Sciences and Engineering Research Council of Canada. </span></em></p><p class="fine-print"><em><span>Tiago Rodrigues Simoes receives funding from the Natural Sciences and Engineering Research Council of Canada and from the Museum of Comparative Zoology, Harvard University. </span></em></p>In 2015, a published article described the fossil of a four-legged snake. New research has revealed that it is in fact a lizard, and the fossil is the centre of a scientific ethics debate.Michael Caldwell, Professor of Vertebrate Palaeontology, University of AlbertaTiago Rodrigues Simoes, Postdoctoral Fellow, Organismic & Evolutionary Biology & Museum of Comparative Zoology, Harvard UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1710522021-11-11T14:40:42Z2021-11-11T14:40:42ZVulnerable lizard species gets hot and bothered in rising temperatures<figure><img src="https://images.theconversation.com/files/429911/original/file-20211103-17-1spa5be.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The sungazer lizard faces a number of threats. Could rising temperatures be among them?</span> <span class="attribution"><span class="source">Dennis W Donohue/Shutterstock</span></span></figcaption></figure><p>Reptiles probably don’t spring to mind when you think of species likely to be affected by rising global temperatures. After all, since they’re often found in hot environments, they’re able to withstand high temperatures and can reduce water loss through their skin.</p>
<p>Despite the ability to withstand high temperatures within their environment, reptiles depend on access to specific thermal environments to optimise various bodily functions. These include metabolism – converting food to energy – and reproduction. That means significant increases in temperature of the kind being <a href="https://www.climate.gov/news-features/understanding-climate/climate-change-global-temperature#">increasingly recorded</a> in many parts of the world could potentially have a negative effect on reptiles.</p>
<p>Although more than <a href="https://www.sanbi.org/wp-content/uploads/2018/04/tolley-et-al-2016-african-reptile-conservation.pdf">1600 of the 9400 reptile species globally</a> can be found on the African continent, there has been almost no research conducted on the effect of climate change on African reptiles. This is partly because of the evasive nature of many reptile species, and also because funding is limited. </p>
<p>To start filling this knowledge gap, <a href="https://www.tandfonline.com/doi/abs/10.1080/15627020.2021.1980103">we studied</a> how higher temperatures affect the <a href="https://www.sanbi.org/animal-of-the-week/giant-girdled-lizard/">sungazer lizard</a> (<em>Smaug giganteus</em>). These charismatic reptiles are endemic to South Africa’s highveld. They are <a href="https://www.iucnredlist.org/species/5336/115650269">already threatened</a> by habitat destruction and illegal collection for the pet and traditional medicine trades. Captive breeding attempts have not worked, which sets the species back further. </p>
<p>We wanted to know what higher temperatures in South Africa will mean for endemic species like the sungazer lizard. Specifically, we wanted to test how being exposed to higher temperatures affected the lizards’ adrenocortical activity as seen in glucocorticoid secretion. Once an animal is exposed to a possible stressor, such as <a href="https://www.nature.com/articles/s41598-020-73354-z">elevated temperatures</a>, the physiological stress response is activated. The animal then secretes more glucocorticoids. </p>
<p>One of this hormone’s primary functions is to provide the required energy and behaviour responses to ensure survival. An elevation in glucocorticoids is adaptive in the short term. But prolonged exposure to elevated levels can have negative effects. These include the suppression of reproductive and immune systems and overall reduced survival. By quantifying an animal’s glucocorticoid levels, scientists can learn crucial information about physiological stress and chances of survival. </p>
<h2>Experiments</h2>
<p>Animals’ bodies respond in various ways to stressors like the presence of a predator, an injury, or a change of surroundings. Physiological responses allow an organism to produce sufficient energy or maintain water balance to escape or recover from a stressful situation. A temporary increase in the secretion of glucocorticoids from the adrenal gland is just one form of response. </p>
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Read more:
<a href="https://theconversation.com/how-predators-may-have-shaped-the-way-some-southern-african-lizards-survive-and-reproduce-145483">How predators may have shaped the way some southern African lizards survive and reproduce</a>
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<p>Once in the bloodstream, glucocorticoids are heavily metabolised in the liver; the hormone metabolites move to the bile before being excreted in faeces. As such, faecal glucocorticoid metabolites can be monitored as a robust proxy for an individual’s adrenocortical activity. Faecal collection also requires almost no direct human-animal interaction, so it’s non-invasive for the animals.</p>
<p>Our research was conducted in a captive environment, at the <a href="https://www.pretoriazoo.org/">National Zoological Garden</a> in Pretoria. Because the species is already vulnerable and there aren’t many available to researchers, we only studied four female and two male animals. </p>
<p>At the National Zoological Garden animals are kept at 27°C-30°C, which is thought to be the ideal range for the species. In the wild they will, of course, experience a wider range of temperatures, depending on the season. For now, though, these will rarely reach the 39°C we used as our high point here.</p>
<p>We divided the animals equally into a control and an experimental group. We let them get used to their new surroundings, at a temperature of 30°C for two weeks. Control animals were then kept at 30°C for another six weeks; the experimental group were kept at 39°C for the same time. Finally, both groups were kept at 30°C for a further three weeks. Study animals were monitored by conservation staff throughout the study to ensure they were safe and healthy.</p>
<p>We collected faecal samples from all study animals daily and quantified their faecal glucocorticoid metabolites (fGCM). Females kept at constant temperatures showed a constant fGCM pattern throughout the study period. Those subjected to higher temperatures showed a sudden spike in fGCM levels immediately following an increase in temperature, as well as during the return period to 30°C. </p>
<p>The male kept at constant temperatures did not show consistent fGCM levels during the study period. The male exposed to higher temperatures, meanwhile, showed a steady increase in fGCM levels as the study progressed.</p>
<p>These results tell us several things. First, the sudden peak in fGCM levels in test females following temperature manipulations suggests the animals perceived the sudden change in environmental temperatures as a stressor. It activated their physiological stress response to restore homeostasis and ensure survival. </p>
<p>This response in female sungazer lizards may be interpreted positively: it could potentially help them to survive in environments where temperatures rise significantly.</p>
<p>The test male’s story is less positive, as he showed increased adrenocortical activity throughout the study period, even when temperatures returned to 30°C. This could indicate that male sungazer lizards are sensitive to any temperature elevation in their immediate environment, despite only displaying a gradual moderate increase in excreted hormone metabolite levels. </p>
<h2>More to understand</h2>
<p>We do not want to make substantial inferences, particularly given the small number of lizards we were able to test. But these findings suggest there are sex-specific differences in stress responses within the species – and a potential further threat to sungazer lizard populations likely to be subjected to higher temperatures in future. </p>
<p>Follow-up studies will be needed. For instance, stress responses should be monitored in wild sungazer lizard populations. It’s also important to remember that different species will react differently to climate change, so more reptile species will need to be studied.</p>
<p><em>Dr Robert Campbell, a wildlife veterinarian, co-authored the study this article is based on.</em></p><img src="https://counter.theconversation.com/content/171052/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Juan Scheun is affiliated with the Mammal Research Institute, University of Pretoria, as a research fellow. </span></em></p><p class="fine-print"><em><span>Trevor McIntyre is affiliated with the Mammal Research Institute, University of Pretoria, as a research fellow. </span></em></p><p class="fine-print"><em><span>Andre Ganswindt does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>By quantifying an animal’s glucocorticoid levels, scientists can learn crucial information about physiological stress and chances of survival.Juan Scheun, Postdoctoral fellow, University of South AfricaAndre Ganswindt, Professor and Director of the Mammal Research Institute, University of Pretoria, University of PretoriaTrevor McIntyre, Associate Professor in Zoology, University of South AfricaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1705602021-10-27T13:20:25Z2021-10-27T13:20:25ZOne sentence in a book leads researchers to a species not seen in over 100 years<figure><img src="https://images.theconversation.com/files/428188/original/file-20211025-15-1uq3sir.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">One of four montane skinks collected by the researchers.</span> <span class="attribution"><span class="source">Wilson Monia</span></span></figcaption></figure><p>It’s been more than 100 years since a live montane skink, <em>Proscelotes aenea</em>, was last spotted. Since then, it hasn’t been clear whether the lizard was extinct or just very good at hiding.</p>
<p>But, thanks to a combination of field work and detective skills, we can now announce that <em>Proscelotes aenea</em> is alive and scuttling around the sandy soils of Lumbo, Mozambique. This is an exciting result for our research project, <a href="http://www.extinctorshy.org">Extinct or Shy</a>. The project highlights what happens when there isn’t a great deal of data available about species in poorly sampled areas: species might be assumed to be extinct when they’re not, so their presence may not be taken into account when countries make conservation decisions.</p>
<p>Our journey to find the elusive montane skink has also highlighted why scientists’ field notes are so important. We used field notes made more than a century ago, as well as a tantalising clue in a naturalist’s autobiography, to narrow down where the skink might be found. </p>
<p>It’s a good reminder to modern researchers to make their fields notes as detailed as possible for future readers. After all, a species that is common at one point in time may not always be so in the future. Any “clues” that might guide researchers years, decades – or even centuries – from now are crucial.</p>
<h2>Hunting for written clues</h2>
<p>The last time the montane skink was recorded by scientists in Lumbo was in 1918. Naturalist Arthur Loveridge collected six specimens during a two-month stay in the area. In his field notes (contained in <a href="https://library.museum.wa.gov.au/fullRecord.jsp?recno=66462">a hard-to-find book</a>), Loveridge wrote that the skinks were found while “the land was cleared of stumps to make tent space for a British camp”. He gave a vague description of that land: at the “British Campsite” – a military base set up during the East African campaign of the First World War – in Lumbo, 3km away from Mozambique Island. There were no coordinates or other reference points to locate the camp site.</p>
<p>Using only these descriptive notes, Wilson Monia, Abdulrabe Jamal and Ali Puruleia, the students responsible for our project’s field work, conducted local interviews that took them to a more inland military base. </p>
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Read more:
<a href="https://theconversation.com/search-for-elusive-skinks-is-filling-gaps-in-mozambiques-biodiversity-data-165635">Search for elusive skinks is filling gaps in Mozambique’s biodiversity data</a>
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<p>It seemed unlikely that this was the seaside site Loveridge wrote about, given its distance from the water. Further online searches didn’t turn up any reference to this campsite; no botanical records were available in <a href="https://www.gbif.org/">online databases</a> that referred to the site in further detail.</p>
<p>The clues we needed turned up unexpectedly in a short passage in Loveridge’s autobiography, <a href="https://www.goodreads.com/book/show/6394887-many-happy-days-i-ve-squandered">Many Happy Days I’ve Squandered</a>, where he briefly describes his stay in Mozambique. The skinks were not mentioned, but he did describe his daily routine. It was a single sentence that led the trio of researchers to the montane skink:</p>
<blockquote>
<p>The camp itself was on a kind of peninsula; on the farther side of Lumbo Bay there were acres of mud flats covered by mangrove trees.</p>
</blockquote>
<p>After a quick look on Google maps, the team immediately found this site and set up new traps. Within two weeks we had found the montane skink; the students have so far recorded four individuals.</p>
<p>In 1918, Lumbo was most likely predominantly covered inland by savanna and by mangrove on the coast. Today it is home to around 20,000 people – double what it was 50 years ago, so far more densely populated than it was during Loveridge’s time. Travelling through the area, you’ll see tar roads and cement houses; there are farms and wetlands, but very little native vegetation remains. </p>
<h2>More work to come</h2>
<p>The project is now collecting important ecological information to map and assess the species. The montane skink is <a href="https://www.iucnredlist.org/species/44978942/44978950">listed as “data deficient”</a> by the <a href="https://www.iucnredlist.org/resources/categories-and-criteria">International Union for the Conservation of Nature</a>. Once more data has been provided, the species may be assessed as range-restricted or threatened; both these categories require countries to put certain protections in place to support the at-risk species.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/we-used-60-year-old-notebooks-to-find-out-why-male-hippos-have-bigger-tusks-than-females-168686">We used 60-year-old notebooks to find out why male hippos have bigger tusks than females</a>
</strong>
</em>
</p>
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<p>Finding the montane skink doesn’t mean that Extinct or Shy’s work is done. The team is also trying to find another species, Boulenger’s legless skink (<em>Scolecoseps boulengeri</em>). There’s even less information about this species than there is about the montane skink; so far our searches have been unsuccessful.</p>
<h2>Detail is key</h2>
<p>One of the biggest lessons to take from this work is that rich detail in field notes is crucial. The level of detail researchers use in their field notes today varies wildly; some provide minimal detail while others document weather, soil type, associated species, micro-habitat and much more. And, although field notes can be stored in online back-ups, a significant number undoubtedly still sit on shelves, in attics and in moving boxes as researchers progress through their field seasons and careers. This comes with a risk that the data can easily be lost forever.</p>
<p>When it comes to reptiles like skinks, many modern surveys are conducted using both trapping and active search methods. Explicitly describing how many of each species are recorded, as well as where and how they were obtained, can provide valuable details for studies that aim to reproduce earlier results. </p>
<p>This is increasingly important in areas that are rapidly changing due to urbanisation, expanding agriculture and that are experiencing adverse effects of climate change.</p>
<p>It was a description of a campsite that led us to find the montane skink again after 100 years without a scientific record in the area. We hope that in the future field biologists, with support and encouragement from editors and journals, will include such relevant information alongside species checklists in their scientific publications.</p><img src="https://counter.theconversation.com/content/170560/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Harith Omar Morgadinho Farooq receives funding from Rufford's Foundation.
Harith Omar Morgadinho Farooq is also affiliated with Lúrio University, Mozambique</span></em></p><p class="fine-print"><em><span>Allison Perrigo receives funding from Kungl. Vetenskaps- och Vitterhets-Samhället (KVVS). </span></em></p>Detailed field notes can help researchers track down rare species.Harith Omar Morgadinho Farooq, Post-doc, University of GothenburgAllison Perrigo, Director of the Gothenburg Global Biodiversity Centre, University of GothenburgLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1629982021-09-12T20:02:37Z2021-09-12T20:02:37ZSaving these family-focused lizards may mean moving them to new homes. But that’s not as simple as it sounds<figure><img src="https://images.theconversation.com/files/407135/original/file-20210618-15-1ifhpwt.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C1599%2C1077&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Holly Bradley</span>, <span class="license">Author provided</span></span></figcaption></figure><p><em><strong><a href="https://theconversation.com/au/topics/am-i-not-pretty-enough-106740">Am I not pretty enough?</a></strong> This article is part of The Conversation’s series introducing you to unloved Australian animals that need our help.</em></p>
<hr>
<p>Spiny-tailed skinks (<em>Egernia stokesii badia</em>), known as meelyu in the local Badimia language in Western Australia, are highly social lizards that live together in family groups — an uncommon trait among reptiles. </p>
<p>They’re culturally significant to the Badimia people but habitat degradation and mining has put them under threat of extinction.</p>
<p>These sturdy, mottled lizards — which live in colonies in the logs of fallen trees and branches — are a candidate for what researchers call “mitigation translocation”. </p>
<p>That’s where wildlife are relocated away from high-risk areas (such as those cleared for urban development or mining) to lower risk areas.</p>
<p>It might sound simple. But <a href="https://scholar.google.com.au/citations?view_op=view_citation&hl=en&user=orU0UxkAAAAJ&citation_for_view=orU0UxkAAAAJ:u5HHmVD_uO8C">research</a> shows these mitigation translocation decisions are often made on an ad hoc basis, without a long-term strategic plan in place.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/407138/original/file-20210618-25-1l4cc46.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/407138/original/file-20210618-25-1l4cc46.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/407138/original/file-20210618-25-1l4cc46.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/407138/original/file-20210618-25-1l4cc46.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/407138/original/file-20210618-25-1l4cc46.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/407138/original/file-20210618-25-1l4cc46.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/407138/original/file-20210618-25-1l4cc46.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Example of the range in individual size/age occupying the same permanent log pile structure within the Mid West region of Western Australia.</span>
<span class="attribution"><span class="source">Holly Bradley</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>Not enough pre-planning or follow-up</h2>
<p>There has been much research into assisted relocation of larger, charismatic <a href="https://www.cambridge.org/core/journals/oryx/article/bias-and-dispersal-in-the-animal-reintroduction-literature/BAB3FC3B2FE61B60CDC4273373624569">mammals and birds</a>. But other animals, such as reptiles with a <a href="https://conbio.onlinelibrary.wiley.com/doi/full/10.1046/j.1523-1739.1998.97253.x">less positive social image</a>, have been less widely studied.</p>
<p>Our <a href="https://scholar.google.com.au/citations?view_op=view_citation&hl=en&user=orU0UxkAAAAJ&citation_for_view=orU0UxkAAAAJ:u5HHmVD_uO8C">recent research</a> has found there is often little pre-planning or follow-up to monitor success of mitigation translocations, even though <a href="https://www.thebhs.org/publications/the-herpetological-journal/early-publication/3302-1-killing-them-softly-a-review-on-snake-translocation-and-an-australian-case-study">reptile mitigation translocations</a> do take place, sometimes on a large scale.</p>
<p>In fact, <a href="https://conbio.onlinelibrary.wiley.com/doi/full/10.1111/cobi.13667">fewer than 25%</a> of mitigation translocations worldwide actually result in long-term self-sustaining populations.</p>
<p>Mitigation translocation methods are also not being improved. <a href="https://conbio.onlinelibrary.wiley.com/doi/full/10.1111/cobi.13667">Fewer than half</a> of published mitigation translocation studies have explicitly compared or tested different management techniques. </p>
<p>Mitigation translocation studies also rarely consider long-term implications such as how relocated animals can <a href="https://www.sciencedirect.com/science/article/pii/S0169534707003345?casa_token=YabqE7E6hIMAAAAA:9CbRKh_13KGM3T6pAYEo8Zl4pthuzYGamQjPXaK3FWCzQAD3g50tPiHS6jZCqksXhIglU1Sb">impact the site</a> to which they are moved — for example, if the ecosystem has limited capacity to support the relocated animals.</p>
<p>But it’s not just about ecosystem benefits. Preservation of species such as meelyu also has cultural benefits — but mitigation translocation can only be part of the solution if it’s done strategically.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/hundreds-of-australian-lizard-species-are-barely-known-to-science-many-may-face-extinction-161572">Hundreds of Australian lizard species are barely known to science. Many may face extinction</a>
</strong>
</em>
</p>
<hr>
<h2>The meelyu: a totem species</h2>
<p>As part of Holly Bradley’s research into understanding how to protect meelyu from further loss in numbers, she had the privilege to meet with Badimia Indigenous elder, Darryl Fogarty, who identified meelyu as his family’s totem.</p>
<p>Totemic species can represent a person’s connection to their nation, clan or family group. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/407137/original/file-20210618-16484-bsnotp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/407137/original/file-20210618-16484-bsnotp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/407137/original/file-20210618-16484-bsnotp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/407137/original/file-20210618-16484-bsnotp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/407137/original/file-20210618-16484-bsnotp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/407137/original/file-20210618-16484-bsnotp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/407137/original/file-20210618-16484-bsnotp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=565&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The meelyu or Western Spiny-tailed Skink is significant to the Badimia people and require translocation as part of mine site restoration and mitigation of population loss.</span>
<span class="attribution"><span class="source">Holly Bradley</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Unfortunately, Darryl Fogarty cannot remember the last time he saw the larger meelyu in the area. The introduction of European land management and feral species into Western Australia has upset the ecosystem balance — and this also has cultural consequences.</p>
<p>Preserving totemic fauna in their historic range can be a critical component of spiritual connection to the land for Indigenous groups in Australia. </p>
<p>In the past, this spiritual accountability for the stewardship of a totem has helped protect species over the long term, with this responsibility passed down between generations.</p>
<p>Before European colonisation, this traditional practice helped to preserve biodiversity and maintain an abundance of food supplies.</p>
<p>A strategic approach to future meelyu relocations from areas of active mining is crucial to prevent further population losses — for both ecological and cultural reasons. </p>
<h2>Good mitigation translocation design</h2>
<p>If we are to use mitigation translocation to shore up their numbers, we need effective strategies in place to boost the chance it will actually help the meelyu.</p>
<p>Good mitigation translocation design includes factors such as:</p>
<ul>
<li><p>selecting a good site and understanding properly whether it can support new wildlife populations</p></li>
<li><p>having a good understanding of the animal’s ecological needs and how they fit with the environment to which they’re moving</p></li>
<li><p>using the right methods of release for the circumstances. For example, is it better to use a <a href="https://www.publish.csiro.au/WR/WR14257">soft release</a> method, where an individual animal is gradually acclimatised to its new environs over time? Or a <a href="https://www.publish.csiro.au/WR/WR14257">hard release</a> method, where the animal is simply set free in its new area?</p></li>
<li><p>having a good understanding of the cultural factors involved.</p></li>
</ul>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1008507987072184321"}"></div></p>
<h2>A holistic approach</h2>
<p>A holistic approach to land management and restoration practice considers both cultural and <a href="https://www.frontiersin.org/articles/10.3389/fevo.2017.00159/full">ecological</a> significance.</p>
<p>It supports the protection and return of healthy, functioning ecosystems — as well as community well-being and connection to nature.</p>
<p>Mitigation translocation could have a role to play in protection of culturally significant wildlife like the meelyu, but only when it’s well planned, holistic and part of a long term strategy.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/photos-from-the-field-australia-is-full-of-lizards-so-i-went-bush-to-find-out-why-146020">Photos from the field: Australia is full of lizards so I went bush to find out why</a>
</strong>
</em>
</p>
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<img src="https://counter.theconversation.com/content/162998/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Holly Bradley has received funding from the Gunduwa Regional Conservation Association as part of her research.</span></em></p><p class="fine-print"><em><span>Bill Bateman and Darryl Fogarty do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Spiny-tailed skinks, also known as meelyu, are culturally significant to the Badimia people in Western Australia. But habitat degradation and mining have put them at threat of extinction.Holly Bradley, PhD candidate, Curtin UniversityBill Bateman, Associate professor, Curtin UniversityDarryl Fogarty, Badimia Elder, Indigenous KnowledgeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1662572021-08-23T16:17:17Z2021-08-23T16:17:17ZLizards, snakes and turtles: Dispelling the myths about reptiles as pets<figure><img src="https://images.theconversation.com/files/417105/original/file-20210819-15-1pi9z04.jpg?ixlib=rb-1.1.0&rect=40%2C16%2C5422%2C3620&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Leopard geckos make fun and entertaining pets.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>Reptiles are all the rage. Mochi the bearded dragon is a viral sensation, <a href="https://ca.news.yahoo.com/bearded-dragon-comes-running-towards-211839614.html">with over 1.8 million views on YouTube</a>. Meanwhile, Chris Pratt is <a href="https://www.reptilesmagazine.com/actor-chris-pratt-takes-his-bearded-dragon-out-for-a-walk/">singing to his bearded dragon while walking it on a leash</a>, and he is just one of <a href="https://www.reptiles.swelluk.com/blog/10-celebrity-reptile-owners/">many other celebrities</a> with pet reptiles. It is obvious that having reptiles as pets has gained popularity in recent years. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/D4-VgAeUssI?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Mochi the bearded dragon responds to his name being called.</span></figcaption>
</figure>
<p>But there is a growing number of people opposed to <a href="https://www.floridatoday.com/story/news/2021/02/25/emotions-proposed-florida-reptile-ban-run-raw/4553754001/">owning these animals as pets</a>. Their concerns range from reptiles posing a serious danger to public health to beliefs about reptiles being too cold to love. Why do reptiles get a bad rap?</p>
<h2>Reptile-borne diseases</h2>
<p>Critics of reptile pet ownership often state that <a href="https://arav.org/salmonella-bacteria-reptiles/">reptiles are riddled with diseases</a>, and while it is true that reptiles do harbour disease, the risk is often far lower than people realize. This fear may be due to outbreaks of salmonella in people that occurred nearly half a century ago: In the 1970s, turtles suddenly became a popular pet, and reptile-borne salmonella incidences increased, representing about <a href="https://doi.org/10.1093/oxfordjournals.aje.a121418">11 per cent of all human cases</a>. </p>
<p>In North America, people are more likely to acquire salmonella from consuming animal products. Education campaigns and legislation in the 1990s led to a significant reduction in reptile-borne salmonella, <a href="https://dx.doi.org/10.3201/eid2207.150685">decreasing it to just six per cent of cases</a>. </p>
<p>However, close study of reptile-caused illnesses in humans has only examined trends up to the early 2000s, so public health data may be subject to change <a href="https://doi.org/10.2807/1560-7917.ES.2016.21.34.30324">as reptiles increase in popularity</a>.</p>
<p>Interestingly, although diseases are highlighted as a reason to avoid pet reptiles, pet mammals like dogs and cats have been repeatedly linked to a variety of health problems, <a href="https://avmajournals.avma.org/doi/pdf/10.2460/javma.252.8.945">such as rabies</a> <a href="https://asthma.ca/get-help/asthma-triggers/pets-asthma/">and asthma</a>. Yet these dangers are deemed acceptable by society, despite the public health risks (<a href="https://www.healthlinkbc.ca/health-topics/hw181108">rabies is incurable and fatal</a>).</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/417106/original/file-20210819-15-egca5x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A turtle with a red streak on its head surrounded by greenery" src="https://images.theconversation.com/files/417106/original/file-20210819-15-egca5x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/417106/original/file-20210819-15-egca5x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/417106/original/file-20210819-15-egca5x.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/417106/original/file-20210819-15-egca5x.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/417106/original/file-20210819-15-egca5x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/417106/original/file-20210819-15-egca5x.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/417106/original/file-20210819-15-egca5x.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Turtles, like this red-eared slider, became popular as household pets in the 1970s.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<h2>Companionship and entertainment</h2>
<p>Another common critique is that reptiles simply do not make good pets. This belief stems from the view that reptiles are lumbering, boring creatures. However, <a href="https://doi.org/10.1136/vr.104296">this could not be further from the truth</a>. </p>
<p>There are some incredible examples of reptile nimbleness. For example, <a href="https://jhupbooks.press.jhu.edu/title/secret-social-lives-reptiles">basilisks can run on two legs on the surface of water for more than 20 metres, and crocodiles can use their massive jaws to delicately move their babies and eggs without damaging them</a>. Some lizards can <a href="https://doi.org/10.1098/rsbl.2011.0480">solve food puzzles</a> and <a href="https://doi.org/10.1007/s10071-014-0803-7">tortoises and bearded dragons can take cues from others of the same species to speed up problem-solving tasks</a>, both of which are abilities <a href="http://doi.org/10.1093/oxfordhb/9780199738182.013.0008">once thought to be present only in birds and mammals</a>. </p>
<p>While affection is harder to prove using current scientific methods, <a href="https://doi.org/10.19227/jzar.v9i2.540">tests have shown that some tortoises</a> (likely dependent on personality) <a href="https://doi.org/10.1002/zoo.21227">prefer having their shells scratched by familiar humans</a> to food or toys when making a choice.</p>
<h2>Reptile welfare</h2>
<p>Beyond the risks for people, owning a reptile does pose some threat to the animals themselves. While there is no evidence that <a href="https://doi.org/10.1136/vr.104296">reptiles suffer disproportionately poor welfare compared to other pets</a>, it is easy to access misleading and conflicting information online. Well-intentioned owners can end up keeping reptiles in substandard conditions, <a href="https://doi.org/10.1136/vr.k4836">eventually causing a variety of preventable health issues</a>. </p>
<p>Due to their ectothermic (cold-blooded) nature, reading body language can be tricky, making it difficult to tell when reptiles are suffering. Making things worse, reptiles can often endure severe health conditions longer than mammals. Ultimately, this means that <a href="https://www.chippingnortonvets.co.uk/uploads/Factors%20contributing%20to%20poor%20welfare%20of%20pet%20reptiles.pdf">reptiles can be kept in neglectful conditions for months, or even years</a>. </p>
<p>Thankfully, some <a href="https://www.facebook.com/groups/AdvancingHerpHusbandry/">reptile welfare groups on social media</a> are doing their best to collect and communicate the most up-to-date standards of reptile care. Herpetologists — who study reptiles and amphibians — are <a href="https://doi.org/10.1016/j.applanim.2021.105324">continually refining</a> the best husbandry practices and methods for evaluating reptile welfare. </p>
<h2>Reptile abuse</h2>
<p>Outdated beliefs about reptiles, often spurred on by a misguided distrust, can do real harm by allowing reptile mistreatment to persist. For example, perhaps one of the most astonishingly cruel reptile-related practices are the <a href="https://www.biologicaldiversity.org/campaigns/outlawing_rattlesnake_roundups/index.html">annual rattlesnake rodeos taking place in the southern United States</a>. </p>
<p>Rattlesnakes are taken from the wild and stored for up to eight months, usually without food, water or regular cage maintenance. If the snakes survive this process, <a href="https://commonreader.wustl.edu/c/beauty-and-the-beast-at-the-worlds-largest-rattlesnake-roundup/">they are brought to the rodeo where they are physically beaten, taunted, stomped on or hastily decapitated all while fully conscious</a>. </p>
<p>The manner in which snakes are treated at these events would cause mass outrage if the same practices were performed on any mammal or bird — so why is it acceptable for a reptile? </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/U6TfBBN8vqs?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">A National Geographic story on the Sweetwater, Texas, rattlesnake roundup.</span></figcaption>
</figure>
<h2>Championing reptiles</h2>
<p>Perhaps, through the proper ownership of reptiles as pets, and by dispelling the myths surrounding them, <a href="https://doi.org/10.3390/ani9100821">we can raise awareness of their cognitive abilities and better appreciate their unique appeal</a>.</p>
<p>Though often overlooked, reptiles can make incredible pets. Many owners find themselves captivated by their stoic beauty, and others find even the simplest behaviour endearing. With proper education, owners are able to care for a pet reptile for many years in a way that ensures the health of both the animal and their owner.</p>
<p>Pet ownership may inspire positive change for the welfare of reptiles, putting an end to inhumane practices and promoting conservation goals <a href="http://doi.org/10.12966/abc.08.01.2015">for one of the most underfunded and under-researched groups of animals</a>. </p>
<p>In light of all this, perhaps it is time we show some warmth to our cold-blooded companions.</p><img src="https://counter.theconversation.com/content/166257/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Melanie Denomme receives support from Natural Sciences and Engineering Research Council of Canada given to Glenn Tattersall.</span></em></p><p class="fine-print"><em><span>Glenn Tattersall receives funding from Natural Sciences and Engineering Research Council of Canada. </span></em></p>Reptiles get a bad rap, but this is because they’re misunderstood. Promoting healthy reptile pet ownership can contribute to conservation and education efforts.Melanie Denomme, PhD Student, Biological Sciences, Brock UniversityGlenn J Tattersall, Professor, Biological Sciences, Brock UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1656352021-08-15T09:02:56Z2021-08-15T09:02:56ZSearch for elusive skinks is filling gaps in Mozambique’s biodiversity data<figure><img src="https://images.theconversation.com/files/415430/original/file-20210810-19-p5l32o.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A specimen of _Proscelotes aenea_ collected by Loveridge in 1918 in Lumbo, Mozambique, now kept at the Museum of Comparative Zoology, Harvard University.
</span> <span class="attribution"><span class="source">Licensed under http://creativecommons.org/licenses/by-nc-sa/3.0/</span></span></figcaption></figure><p>Every morning the phone buzzes, many times in short succession, as the students send photo after photo of the snakes, frogs and lizards that have been caught in various traps the previous day. We scroll through the images. Again - no <em>Scolecoseps boulengeri</em>. No <em>Proscelotes aenea</em>.</p>
<p>These two burrowing skinks – a type of lizard – were discovered in Lumbo, Northern Mozambique, in the 1920s. During this period, naturalists often used the readily available infrastructure at military bases during the East African Campaign of World War I as base camps for sampling. But then, the war ended and the naturalists stopped collecting at these sites. After that, the two skink species, assumed to be endemic to Mozambique, were not recorded again. Why?</p>
<p>We’re not entirely sure. It is possible, though, that the skink species are still there – they just haven’t been spotted because no one has been looking. This is a sadly common problem. Despite being an exceptional area for biodiversity – with a variety of habitats ranging from tropical savannahs up to highland mountains and down to coastal mangroves – northern Mozambique is <a href="https://doi.org/10.1093/sysbio/syaa090">severely undersampled</a>, even by African standards. There simply isn’t much data about on the area’s species. </p>
<p>This is partly due to the fact that some places are more accessible than others for various reasons. Parts of the country have been historically inaccessible due to civil war, and other areas are now unreachable <a href="https://theconversation.com/mozambiques-own-version-of-boko-haram-is-tightening-its-deadly-grip-98087">due to an ongoing insurgency</a>. Beyond accessibility issues, most field surveys are conducted by international teams, which tend to be more limited by time and require more resources to carry out the work. </p>
<p>Still, these skinks are thought to occur in the sandy soils of easily accessible beaches, in areas that are much more populated now than 100 years ago. Sites such as this make an excellent venue to stage a hunt for long-lost species. </p>
<p><a href="https://www.rufford.org/projects/harith-farooq/extinct-or-just-shy/">Our project, “Extinct or Shy”</a>, puts the problem of data deficient species in poorly sampled localities in the spotlight. The project asks whether species that haven’t been seen in many decades are actually extinct, or just “shy”. Ambitious students from a <a href="http://www.unilurio.ac.mz/unilurio/en/">university</a> close to the small town <a href="https://doi.org/10.1111/j.1469-7998.1920.tb07639.x">where the two burrowing skinks were discovered</a> are leading the hunt for answers.</p>
<h2>Africa’s widespread sampling deficiency</h2>
<p>As we’ve pointed out in <a href="https://academic.oup.com/sysbio/article/70/3/623/6030962">earlier research</a>, species distribution data – or a lack thereof – can have a major bearing on how a country’s <a href="http://www.keybiodiversityareas.org/">Key Biodiversity Areas</a> and protected areas are designated. Even though studies have shown that <a href="https://doi.org/10.1111/cobi.12372">data deficient species usually end up in threatened categories</a>, they are still not considered when proposing Key Biodiversity Areas, due to the uncertainty of their status.</p>
<p>However, once found or “rediscovered”, well-documented instances of rare species can trigger Key Biodiversity Area status, spearhead conservation efforts and potentially safeguard against extinctions. </p>
<p>The International Union for the Conservation of Nature (IUCN) lists 3,381 African species as “<a href="https://www.iucnredlist.org/">data deficient</a>”; 283 of these may occur in Mozambique. These are the species that we know, or suspect, occur in certain localities, but that lack sufficient data to be assessed according to the rigorous <a href="https://www.iucnredlist.org/resources/categories-and-criteria">IUCN Assessment Criteria</a>. The missing information may consist of precise localities, the species’ ecology, or population trends, for example.</p>
<figure class="align-center ">
<img alt="A light pink lizard-like creature without feet is pictured with a tag around its neck displaying scientific details. There is a ruler above it to denote its size." src="https://images.theconversation.com/files/415433/original/file-20210810-17-u6n00d.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/415433/original/file-20210810-17-u6n00d.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=420&fit=crop&dpr=1 600w, https://images.theconversation.com/files/415433/original/file-20210810-17-u6n00d.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=420&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/415433/original/file-20210810-17-u6n00d.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=420&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/415433/original/file-20210810-17-u6n00d.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=527&fit=crop&dpr=1 754w, https://images.theconversation.com/files/415433/original/file-20210810-17-u6n00d.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=527&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/415433/original/file-20210810-17-u6n00d.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=527&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A specimen of <em>Scolecoseps boulengeri</em> in the Museum of Comparative Zoology, Harvard University.</span>
<span class="attribution"><span class="source">Museum of Comparative Zoology, Harvard University/icensed under http://creativecommons.org/licenses/by-nc-sa/3.0</span></span>
</figcaption>
</figure>
<p>That’s why our “Extinct or shy?” team is hard at work to locate the elusive skinks. Four students from Lúrio University – Abdulrabe Jamal, Ali Puruleia, Iassine Amade, and Wilson Monia – work alongside collaborators Cristóvão Nanvonamuquitxo and Yasalde Massigue. They are checking the traps daily for an entire year, taking tissue samples and saving vouchers (preserved specimens) for <a href="https://theconversation.com/why-we-still-collect-butterflies-41485">natural history collections</a>. The project will continue through April 2022. </p>
<p>In the process they are not only gathering the data necessary to reassess the conservation status of the skinks; they are also amassing an extensive understanding of the other reptiles and amphibians that occur in the region.</p>
<p>There are two main scenarios for each species in this project. If the species is found, its habitat could be protected via implementation of Key Biodiversity Area status or conservation initiatives. If we don’t find the species, it may already be extinct, or may exist in such small numbers that it may soon go extinct without proper intervention.</p>
<p>If these skinks show up again, this time it will be Mozambican researchers who find them and co-write the paper to describe the finding. This is significant because they will be describing the biodiversity of their own country and strengthening locally held taxonomic expertise. It is also extremely practical.</p>
<h2>Local universities can lead the way</h2>
<p>Mozambique has 11 accredited universities, spread out across the country. Several of them have multiple, distributed campuses offering natural sciences-related curricula. These institutions could lead initiatives to provide baseline information on poorly known species. That is why we’ve partnered with our Lúrio University colleagues on this project.</p>
<p>Many data deficient species are not easy to find, and will therefore require lengthy field experiments to collect information. This could be arranged between supervisors and students at local universities by equipping them to carry out field studies in adjacent areas, with support from international experts as necessary. </p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/415614/original/file-20210811-17-ptxh43.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/415614/original/file-20210811-17-ptxh43.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/415614/original/file-20210811-17-ptxh43.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/415614/original/file-20210811-17-ptxh43.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/415614/original/file-20210811-17-ptxh43.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/415614/original/file-20210811-17-ptxh43.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/415614/original/file-20210811-17-ptxh43.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">From left to right, Wilson Monia, Abdulrabe Jamal, and Ali Puruleia. At the bottom is collaborator and local coordinator Cristóvão Nanvonamuquitxo.</span>
<span class="attribution"><span class="source">Supplied</span></span>
</figcaption>
</figure>
<p>Issues remain with this system. Mozambique lacks even simple field guides for major groups, including mammals, birds, amphibians and reptiles. Field guides for Eastern and Southern Africa routinely exclude northern portions of the poorly documented country, where taxonomic expertise is rarely held by Mozambican nationals.</p>
<h2>Inclusive research</h2>
<p>For this reason, technology plays a key role in “Extinct or Shy”. Although one of us, Harith, is originally from Mozambique, he now depends on regular connection, usually via WhatsApp, with the students in the field. From Sweden, where we’re both based at the Gothenburg Global Biodiversity Centre, we can identify the specimens in real time and also provide general project guidance. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/tracking-science-a-way-to-include-more-people-in-producing-knowledge-159587">Tracking science: a way to include more people in producing knowledge</a>
</strong>
</em>
</p>
<hr>
<p>After the sampling is complete, the whole team will meet to analyse the data and write up our findings together. We hope that eventually the students will use both their field work skills and experience in the scientific process to lead their own research and document Mozambique’s wonderful biodiversity.</p><img src="https://counter.theconversation.com/content/165635/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Harith Omar Morgadinho Farooq receives funding from The Rufford Foundation (29825-1). </span></em></p><p class="fine-print"><em><span>Allison Perrigo receives funding for this project from Kungl. Vetenskaps- och Vitterhets-Samhället (KVVS). </span></em></p>Species distribution data – or a lack thereof – can have a major bearing on how a country’s Key Biodiversity Areas and protected areas are designated.Harith Omar Morgadinho Farooq, Post-doc, University of GothenburgAllison Perrigo, Director of the Gothenburg Global Biodiversity Centre, University of GothenburgLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1423632021-06-16T12:35:58Z2021-06-16T12:35:58ZSmelling in stereo – the real reason snakes have flicking, forked tongues<figure><img src="https://images.theconversation.com/files/403812/original/file-20210601-15-15hx7un.jpg?ixlib=rb-1.1.0&rect=7%2C0%2C5121%2C3427&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Long misunderstood, snake tongues have fascinated naturalists for centuries.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/red-tailed-green-rat-snake-gonyosoma-oxycephalum-royalty-free-image/499911945">reptiles4all/iStock via Getty Images Plus</a></span></figcaption></figure><p>As dinosaurs lumbered through the <a href="https://www.britannica.com/science/Jurassic-Period">humid cycad forests of ancient South America</a> 180 million years ago, primeval lizards scurried, unnoticed, beneath their feet. Perhaps to avoid being trampled by their giant kin, some of these <a href="https://doi.org/10.1126/sciadv.1500743">early lizards sought refuge underground</a>. </p>
<p>Here they <a href="https://doi.org/10.1093/icb/15.2.455">evolved long, slender bodies and reduced limbs</a> to negotiate the narrow nooks and crevices beneath the surface. Without light, <a href="https://doi.org/10.2307/1439015">their vision faded</a>, but to take its place, an especially acute sense of smell evolved.</p>
<p>It was during this period that these proto-snakes evolved one of their most iconic traits – a <a href="https://theconversation.com/explainer-why-do-snakes-flick-their-tongues-29935">long, flicking, forked tongue</a>. These reptiles eventually returned to the surface, but it wasn’t until the extinction of dinosaurs many millions of years later that they <a href="https://doi.org/10.1186/s12862-015-0358-5">diversified into myriad types of modern snakes</a>.</p>
<p>As an <a href="https://scholar.google.com/citations?hl=en&user=G-2IS0oAAAAJ">evolutionary biologist</a>, I am fascinated by these bizarre tongues – and <a href="https://doi.org/10.1126/science.263.5153.1573">the role they have played in snakes’ success</a>.</p>
<h2>A puzzle for the ages</h2>
<p>Snake tongues are so peculiar they have fascinated naturalists for centuries. Aristotle believed the forked tips provided snakes a <a href="https://archive.org/details/worksofaristotle512aris">“twofold pleasure” from taste</a> – a view mirrored centuries later by French naturalist Bernard Germain de Lacépède, who suggested the twin tips could adhere more closely to “<a href="https://www.biodiversitylibrary.org/item/54321#page/9/mode/1up">the tasty body</a>” of the soon-to-be snack.</p>
<p>A 17th-century astronomer and naturalist, Giovanni Battista Hodierna, thought snakes used their tongues for “<a href="https://doi.org/10.1098/rstl.1683.0010">picking the dirt out of their noses … since they are always grovelling on the ground</a>.” Others contended the tongue captured flies “<a href="http://hdl.loc.gov/loc.gdc/lhbcb.27239">with wonderful nimbleness … betwixt the forks</a>,” or <a href="https://www.biodiversitylibrary.org/item/24612#page/7/mode/1up">gathered air for sustenance</a>.</p>
<p>One of the most persistent beliefs has been that the <a href="https://www.biodiversitylibrary.org/item/31811#page/5/mode/1u">darting tongue is a venomous stinger</a>, a misconception perpetuated by Shakespeare with his many references to “stinging” serpents and adders, “<a href="https://shakespeare.folger.edu/shakespeares-works/richard-ii/act-3-scene-2/?search=adder/#line-3.2.4">Whose double tongue may with mortal touch throw death upon thy … enemies</a>.”</p>
<p>According to the French naturalist and early evolutionist Jean-Baptiste Lamarck, snakes’ limited vision obliged them to use their forked tongues “<a href="https://www.journals.uchicago.edu/doi/pdfplus/10.1086/274830">to feel several objects at once</a>.” Lamarck’s belief that the <a href="https://www.biodiversitylibrary.org/item/31811#page/5/mode/1up">tongue functioned as an organ of touch</a> was the prevailing scientific view by the end of the 19th century.</p>
<h2>Smelling with tongues</h2>
<p>Clues to the true significance of snake tongues began to emerge in the early 1900s when scientists turned their attention to two bulblike organs located just above the snake’s palate, below its nose. Known as Jacobson’s, or vomeronasal, organs, <a href="https://doi.org/10.1016/S0169-5347(00)88953-3">each opens to the mouth through a tiny hole in the palate</a>. Vomeronasal organs are found in a variety of land animals, including mammals, but not in most primates, so humans don’t experience whatever sensation they provide.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/406283/original/file-20210614-126997-r2t1cy.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A diagram showing the location of the vomeronasal organ on a snake." src="https://images.theconversation.com/files/406283/original/file-20210614-126997-r2t1cy.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/406283/original/file-20210614-126997-r2t1cy.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=263&fit=crop&dpr=1 600w, https://images.theconversation.com/files/406283/original/file-20210614-126997-r2t1cy.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=263&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/406283/original/file-20210614-126997-r2t1cy.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=263&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/406283/original/file-20210614-126997-r2t1cy.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=330&fit=crop&dpr=1 754w, https://images.theconversation.com/files/406283/original/file-20210614-126997-r2t1cy.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=330&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/406283/original/file-20210614-126997-r2t1cy.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=330&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Tongue tips deliver odor molecules to the vomeronasal organ.</span>
<span class="attribution"><span class="source">Kurt Schwenk</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Scientists found that vomeronasal organs are, in fact, an offshoot of the nose, lined with similar sensory cells that <a href="https://doi.org/10.1177/000348943404300311">send impulses to the same part of the brain as the nose</a>, and discovered that tiny particles picked up by the tongue tips ended up inside the vomeronasal organ. These breakthroughs led to the realization that snakes use their tongues to collect and transport molecules to their vomeronasal organs – not to taste them, but to smell them.</p>
<p>In 1994, I used film and photo evidence to show that when snakes sample chemicals on the ground, they separate their tongues tips far apart just as they touch the ground. This action allows them to sample odor molecules from <a href="https://doi.org/10.1126/science.263.5153.1573">two widely separated points simultaneously</a>. </p>
<figure>
<img src="https://cdn.theconversation.com/static_files/files/1596/ezgif.com-gif-maker.gif?1622555314">
<figcaption><span class="caption">Sampling two points at once. <i>Credit: Kurt Schwenk</i></span></figcaption>
</figure>
<p>Each tip delivers to its own vomeronasal organ separately, allowing the snake’s brain to assess instantly which side has the stronger smell. Snakes have two tongue tips for the same reason you have two ears – it provides them with directional or “stereo” smell with every flick – a skill that turns out to be extremely useful when following scent trails left by potential prey or mates.</p>
<p>Fork-tongued lizards, the legged cousins of snakes, do something very similar. But snakes take it one step farther.</p>
<h2>Swirls of odor</h2>
<p>Unlike lizards, when snakes collect odor molecules in the air to smell, they oscillate their forked tongues up and down in a blur of rapid motion. To visualize how this affects air movement, graduate student <a href="https://scholar.google.com/citations?hl=en&user=8jJWMBgAAAAJ">Bill Ryerson</a> and I used a laser focused into a thin sheet of light to illuminate tiny particles suspended in the air.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/404121/original/file-20210602-21-1tj11os.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A snake flicking its toungue through a veil of smoke creating two swirls." src="https://images.theconversation.com/files/404121/original/file-20210602-21-1tj11os.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/404121/original/file-20210602-21-1tj11os.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/404121/original/file-20210602-21-1tj11os.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/404121/original/file-20210602-21-1tj11os.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/404121/original/file-20210602-21-1tj11os.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/404121/original/file-20210602-21-1tj11os.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/404121/original/file-20210602-21-1tj11os.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Tongue-flicking creates small eddies in the air, condensing the molecules floating within it.</span>
<span class="attribution"><span class="source">Kurt Schwenk</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>We discovered that the flickering snake tongue generates two pairs of small, swirling masses of air, or vortices, that act like tiny fans, pulling odors in from each side and <a href="https://doi.org/10.1002/jez.725">jetting them directly into the path of each tongue tip</a>. </p>
<p>Since odor molecules in the air are few and far between, we believe snakes’ unique form of tongue-flicking serves to concentrate the molecules and accelerate their collection onto the tongue tips. Preliminary data also suggests that the airflow on each side remains separate enough for snakes to benefit from the same “stereo” smell they get from odors on the ground.</p>
<p>Owing to history, genetics and other factors, natural selection often falls short in creating optimally designed animal parts. But when it comes to the snake tongue, evolution seems to have hit one out of the park. I doubt any engineer could do better.</p>
<p>[<em>You’re smart and curious about the world. So are The Conversation’s authors and editors.</em> <a href="https://theconversation.com/us/newsletters/the-daily-3?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=youresmart">You can read us daily by subscribing to our newsletter</a>.]</p><img src="https://counter.theconversation.com/content/142363/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kurt Schwenk receives funding from The National Science Foundation and The University of Connecticut</span></em></p>Two tongue tips are better than one – an evolutionary biologist explains why snakes have forked tongues.Kurt Schwenk, Professor of Ecology and Evolutionary Biology, University of ConnecticutLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1615722021-06-01T20:10:39Z2021-06-01T20:10:39ZHundreds of Australian lizard species are barely known to science. Many may face extinction<figure><img src="https://images.theconversation.com/files/403481/original/file-20210530-17-i4ac6g.JPG?ixlib=rb-1.1.0&rect=0%2C0%2C6020%2C4019&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">E Vanderduys</span>, <span class="license">Fourni par l'auteur</span></span></figcaption></figure><p>Most of the incredible diversity of life on Earth is yet to be discovered and documented. In some groups of organisms – terrestrial arthropods such as spiders and scorpions, marine invertebrates such as sponges and molluscs, and others – scientists have described fewer than 20% of species.</p>
<p>Even our knowledge of more familiar creatures such as fish and reptiles is far from complete. In our <a href="http://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.3001210">new research</a>, we studied 1,034 known species of Australian lizards and snakes and found we know so little about 164 of them that not even the experts know whether they are fully described or not. Of the remaining 870, almost a third probably need some work to be described properly.</p>
<figure class="align-right ">
<img alt="Map of Australia shaded in colours from blue to red." src="https://images.theconversation.com/files/403295/original/file-20210528-17-gl4crn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/403295/original/file-20210528-17-gl4crn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/403295/original/file-20210528-17-gl4crn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/403295/original/file-20210528-17-gl4crn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/403295/original/file-20210528-17-gl4crn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/403295/original/file-20210528-17-gl4crn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/403295/original/file-20210528-17-gl4crn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Return on investment for taxonomic research on lizards and snakes in Australia. Red areas have high numbers of species and high conservation value. Hotspots include the Kimberley in WA, northern tropical savannas and also far north eastern QLD.</span>
<span class="attribution"><span class="source">R. Tingley</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Documenting and naming what species are out there – the work of taxonomists – is crucial for conservation, but it can be difficult for researchers to decide where to focus their efforts. Alongside our lizard research, we have developed a new “return on investment” approach to identify priority species for our efforts. </p>
<p>We identified several hotspots across Australia where research is likely to be rewarded. More broadly, our approach can help target taxonomic research for conservation worldwide. </p>
<h2>Why we need to look at species more closely</h2>
<p>As more and more species are threatened by land clearing, climate change and other human activities, our research highlights that we are losing even more biodiversity than we know.</p>
<p>Conservation often relies on species-level assessments such as those conducted by the International Union for Conservation of Nature (IUCN) <a href="https://www.iucnredlist.org">Red List</a>, which lists threatened species. Although new species are being discovered all the time, a key problem is that already named “species” may harbour multiple undocumented and unnamed species. This hidden diversity remains invisible to conservation assessment.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/403299/original/file-20210528-19-1j58gc0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/403299/original/file-20210528-19-1j58gc0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/403299/original/file-20210528-19-1j58gc0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/403299/original/file-20210528-19-1j58gc0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/403299/original/file-20210528-19-1j58gc0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/403299/original/file-20210528-19-1j58gc0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/403299/original/file-20210528-19-1j58gc0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The Roma Earless Dragon (<em>Tympanocryptis wilsoni</em>), described in 2014, lives only in grasslands in the western Darling Downs QLD and has recently been listed as Vulnerable in Queensland.</span>
<span class="attribution"><span class="source">A. O'Grady</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>One such example are the Grassland Earless Dragons (<em>Tympanocryptis</em> spp.) found in the temperate native grasslands of south-eastern Australia. These small secretive lizards were grouped within a single species (<em>Tympanocryptis pinguicolla</em>) and listed as Endangered on the IUCN Red List. </p>
<p>But recent taxonomic research split this single species into four, each occurring in an isolated region of grasslands. One of these new species may represent the first extinction of a reptile on mainland Australia and the other three have a high probability of being threatened. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-were-not-giving-up-the-search-for-mainland-australias-first-extinct-lizard-117831">Why we're not giving up the search for mainland Australia's 'first extinct lizard'</a>
</strong>
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</p>
<hr>
<p>Scientists call documenting and describing species “taxonomy”. Our research shows the importance of prioritising taxonomy in the effort to conserve and protect species. </p>
<h2>Taxonomists at work</h2>
<p>Many government agencies do take some account of groups smaller than species in their conservation efforts, such as distinct populations. But these are often ambiguously defined and lack formal recognition, so they are not widely used. That’s where taxonomists come in, to identify species and describe them fully.</p>
<p>Our new research was a collaboration of 30 taxonomists and systematists, who teamed up to find a good way of working out which species should be a priority for taxonomic research for conservation outcomes. This new approach compares the amount of work needed with the likelihood of finding previously unknown species that are at risk of extinction.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/403297/original/file-20210528-14-109lmby.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/403297/original/file-20210528-14-109lmby.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/403297/original/file-20210528-14-109lmby.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/403297/original/file-20210528-14-109lmby.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/403297/original/file-20210528-14-109lmby.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/403297/original/file-20210528-14-109lmby.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/403297/original/file-20210528-14-109lmby.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Barrier Range Dragon (<em>Ctenophorus mirrityana</em>), described in 2013, is restricted to rocky ranges in western NSW and is listed as Endangered in NSW.</span>
<span class="attribution"><span class="source">S. Wilson</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The research team, who are experts on the taxonomy and systematics of Australia’s reptiles, implemented this new approach on Australian lizards and snakes. This group of reptiles is ideal as a test case because Australia is a global hotspot of lizard diversity – and we also have a strong community of taxonomic experts.</p>
<h2>Australia’s lizards and snakes</h2>
<p>Of the 1,034 Australian lizard and snake species, we were able to assess whether 870 of them may contain undescribed species. This means we know so little about the remaining 164 species that even the experts could not make an informed opinion on whether they contain hidden diversity. There is so much still to learn!</p>
<p>Of the 870 species experts could assess, they determined 282 probably or definitely needed more taxonomic research. Mapping the distributions of these species indicated hotspot regions for this taxonomic research, including the Kimberley, the Tanami Desert region, western Victoria and offshore islands (such as Tasmania, Lord Howe and Norfolk Islands). Some areas in the Kimberley region had more than 60 species that need further taxonomic research.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/403293/original/file-20210528-23-1dfev38.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/403293/original/file-20210528-23-1dfev38.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/403293/original/file-20210528-23-1dfev38.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/403293/original/file-20210528-23-1dfev38.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/403293/original/file-20210528-23-1dfev38.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/403293/original/file-20210528-23-1dfev38.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/403293/original/file-20210528-23-1dfev38.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">In this map, red hotspot areas have lower species diversity but still a very high average return on investment. National hotspots include Tasmania, western Victoria and the Tanami Desert region in WA and NT.</span>
<span class="attribution"><span class="source">R. Tingley</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>We found 17.6% of the 282 species that need more taxonomic research contained undescribed species that would probably be of conservation concern, and 24 had a high probability of being threatened with extinction. Taxonomists know that there are undescribed species because there is some data available already but the description of these species – the process of defining and naming – has not been done. </p>
<p>These high-priority species belong to a range of families including geckos, skinks and dragons found across Australia.</p>
<p>The high number of undescribed species, especially those with significant likelihood of being endangered, was a shock to even the experts. The IUCN currently estimates only 6.3% of Australian lizards and snakes require taxonomic revision, but this is obviously a significant underestimate.</p>
<h2>A race against extinction</h2>
<p>Beyond lizards, there is a huge backlog of species awaiting description. </p>
<p>Recent projects have used genetic analyses to discover unknown species, including a $180 million global BIOSCAN effort aiming to <a href="https://www.sciencemag.org/news/2019/06/180-million-dna-barcode-project-aims-discover-2-million-new-species">identify millions of new species</a>. However, genetics is only a first step in the formal recognition of species. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/about-500-000-australian-species-are-undiscovered-and-scientists-are-on-a-25-year-mission-to-finish-the-job-161793">About 500,000 Australian species are undiscovered – and scientists are on a 25-year mission to finish the job</a>
</strong>
</em>
</p>
<hr>
<p>The taxonomic process of documenting, describing and naming species requires multiple further steps. These steps include a comprehensive diagnostic assessment using a combination of evidence, such as genetics and morphology, to uniquely distinguish each species from another. This process requires a high level of familiarity and scholarship of the group in question.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/403300/original/file-20210528-14-1hs18dy.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/403300/original/file-20210528-14-1hs18dy.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/403300/original/file-20210528-14-1hs18dy.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/403300/original/file-20210528-14-1hs18dy.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/403300/original/file-20210528-14-1hs18dy.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/403300/original/file-20210528-14-1hs18dy.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/403300/original/file-20210528-14-1hs18dy.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The Mt Elliot Sunskink (<em>Lampropholis elliotensis</em>), described in 2018, is found in leaf litter of highland rainforest above 600m on Mt Elliot in Bowling Green Bay National Park. Queensland, and is probably Vulnerable.</span>
<span class="attribution"><span class="source">C. Hoskin</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Among the Australian lizards and snakes alone, there is a backlog of 59 undescribed species for which only the final elements of taxonomic research are awaiting completion.</p>
<p>To work through these taxonomic backlogs – let alone species that are so far entirely unknown – resources need to be invested in taxonomy, including research funding and increased provision of viable career paths. </p>
<p>Without taxonomic research, the conservation assessment of these undocumented species will not proceed. There are untold numbers of species needing taxonomic research that are already under threat of extinction. If we don’t hurry, they may go extinct before we even know they exist.</p><img src="https://counter.theconversation.com/content/161572/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jane Melville undertook this work supported by an Australian Fulbright Commission scholarship.</span></em></p><p class="fine-print"><em><span>Reid Tingley receives funding from the Australian Research Council.</span></em></p>There are too many little-understood species for scientists to study them all. A new approach helps decide which ones to tackle first.Jane Melville, Senior Curator, Terrestrial Vertebrates, Museums Victoria Research InstituteReid Tingley, Lecturer, Monash UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1504962020-12-15T13:20:28Z2020-12-15T13:20:28ZVirgin births from parthenogenesis: How females from some species can reproduce without males<figure><img src="https://images.theconversation.com/files/374837/original/file-20201214-17-2nde3j.png?ixlib=rb-1.1.0&rect=0%2C0%2C5463%2C3006&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Getting the job done. A female Asian water dragon (Physignathus cocincinus) produced a daughter (left) without the assistance of a male. </span> <span class="attribution"><a class="source" href="https://nationalzoo.si.edu/news/scientists-confirm-facultative-parthenogenesis-smithsonians-national-zoos-asian-water-dragon">Skip Brown/Smithsonian’s National Zoo</a></span></figcaption></figure><p>An Asian water dragon hatched from an egg at the Smithsonian National Zoo, and her keepers were shocked. Why? Her mother had never been with a male water dragon. Through genetic testing, zoo scientists discovered the newly hatched female, born on Aug. 24, 2016, had been produced through a <a href="https://doi.org/10.1371/journal.pone.0217489">reproductive mode called parthenogenesis</a>.</p>
<p>Parthenogenesis is a Greek word meaning “virgin creation,” but specifically refers to female asexual reproduction. While many people may assume this behavior is the domain of science fiction or religious texts, parthenogenesis is <a href="https://doi.org/10.1038/sdata.2014.15">surprisingly common throughout the tree of life</a> and is found in a variety of organisms, including plants, insects, fish, reptiles and even birds. Because mammals, including human beings, require certain genes to come from sperm, <a href="https://doi.org/10.1159/000090812">mammals are incapable of parthenogenesis</a>.</p>
<h2>Creating offspring without sperm</h2>
<p>Sexual reproduction involves a female and a male, each contributing genetic material in the form of eggs or sperm, to create a unique offspring. The vast majority of animal species reproduce sexually, but females of some species are able to produce eggs <a href="https://www.britannica.com/science/parthenogenesis">containing all the genetic material required for reproduction</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/373966/original/file-20201209-19-1x4523.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A microscopic view of a translucent water flea show four round eggs inside." src="https://images.theconversation.com/files/373966/original/file-20201209-19-1x4523.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/373966/original/file-20201209-19-1x4523.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=418&fit=crop&dpr=1 600w, https://images.theconversation.com/files/373966/original/file-20201209-19-1x4523.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=418&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/373966/original/file-20201209-19-1x4523.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=418&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/373966/original/file-20201209-19-1x4523.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=526&fit=crop&dpr=1 754w, https://images.theconversation.com/files/373966/original/file-20201209-19-1x4523.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=526&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/373966/original/file-20201209-19-1x4523.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=526&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A female freshwater water flea (<em>Daphnia magna</em>) carrying parthenogenetic eggs.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/microscopic-view-of-freshwater-water-flea-royalty-free-image/841300586">buccaneership/iStock via Getty Images Plus</a></span>
</figcaption>
</figure>
<p>Females of these species, which include <a href="https://doi.org/10.1002/evl3.30">some wasps</a>, <a href="https://doi.org/10.1086/283761">crustaceans</a> and <a href="https://www.scientificamerican.com/article/asexual-lizards/">lizards</a>, reproduce only through parthenogenesis and are called obligate parthenogens.</p>
<p>A larger number of species experience spontaneous parthenogenesis, best documented in animals kept in zoo settings, like the Asian water dragon at the National Zoo or a <a href="https://doi.org/10.1111/j.1095-8649.2008.02018.x">blacktip shark at the Virginia Aquarium</a>. Spontaneous parthenogens typically reproduce sexually, but may have occasional cycles that produce developmentally ready eggs.</p>
<p>Scientists have learned <a href="https://doi.org/10.1098/rspb.2009.2113">spontaneous parthenogenesis may be a heritable trait</a>, meaning females that suddenly experience parthenogenesis might be more likely to have daughters that can do the same.</p>
<h2>How can females fertilize their own eggs?</h2>
<p>For parthenogenesis to happen, <a href="https://doi.org/10.1534/g3.112.005421">a chain of cellular events must successfully unfold</a>. First, females must be able to create egg cells (oogenesis) without stimulation from sperm or mating. Second, the eggs produced by females need to begin to develop on their own, forming an early stage embryo. Finally, the eggs must successfully hatch. </p>
<p>Each step of this process can easily fail, particularly step two, which requires the chromosomes of DNA inside the egg to double, ensuring a full complement of genes for the developing offspring. Alternatively, the egg can be “faux fertilized” by leftover cells from the egg production process known as <a href="https://doi.org/10.1002/mrd.21266">polar bodies</a>. Whichever method kicks off the development of the embryo <a href="https://doi.org/10.1525/bio.2009.59.7.3">will ultimately determine the level of genetic similarity</a> between the mother and her offspring.</p>
<p>The events that trigger parthenogenesis are not fully understood, but appear to include environmental change. In species that are capable of both sexual reproduction and parthenogenesis, such as <a href="https://doi.org/10.1371/journal.pone.0115099">aphids</a>, stressors like <a href="https://doi.org/10.1111/een.12080">crowding and predation</a> may cause females to switch from parthenogenesis to sexual reproduction, but not the other way around. In at least one <a href="https://doi.org/10.1007/978-90-481-2770-2_15">type of freshwater plankton</a>, <a href="https://doi.org/10.5762/KAIS.2016.17.4.692">high salinity</a> appears to cause the switch.</p>
<h2>Advantages of self-reproduction</h2>
<p>Though spontaneous parthenogenesis appears to be rare, it does provide some benefits to the female who can achieve it. In some cases, it can allow females to generate their own mating partners. </p>
<p>The sex of parthenogenetic offspring is determined by the same method sex is determined in the species itself. For organisms where sex is determined by chromosomes, like the XX female and XY male chromosomes in some insects, fish and reptiles, a parthenogenetic female can produce offspring only with the sex chromosomes she has at hand – which means she will always produce XX female offspring. But for organisms where females have ZW sex chromosomes (such as in snakes and birds), all living offspring produced will either be ZZ, and therefore male, or <a href="https://doi.org/10.1098/rsbl.2010.0793">much more rarely, WW, and female</a>.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"976632933531316224"}"></div></p>
<p>Between 1997 and 1999, <a href="https://doi.org/10.1111/j.1095-8312.2012.01954.x">a checkered gartersnake kept at the Phoenix Zoo</a> gave birth to two male offspring that ultimately survived to adulthood. If a female mated with her parthenogenetically produced son, it would constitute inbreeding. While inbreeding can result in a host of genetic problems, from an evolutionary perspective it’s better than having no offspring at all. The ability of females to produce male offspring through parthenogenesis also suggests that asexual reproduction in nature may be more common than scientists ever realized before. </p>
<p>Biologists have observed, over long periods of time, that <a href="https://doi.org/10.1016/0022-5193(71)90058-0">species that are obligate parthenogens frequently die out</a> from <a href="https://doi.org/10.1038/s41514-018-0025-3">disease</a>, <a href="https://doi.org/10.1073/pnas.87.9.3566">parasitism</a> or <a href="https://doi.org/10.1002/evl3.30">changes in habitat</a>. The inbreeding inherent in parthenogenetic species appears to contribute to their short evolutionary timelines. </p>
<p>Current research on parthenogenesis seeks to understand why some species are capable of both sex and parthenogenesis, and whether occasional sexual reproduction might be enough for a species to survive.</p><img src="https://counter.theconversation.com/content/150496/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mercedes Burns has previously received funding from the National Science Foundation. </span></em></p>Parthenogenesis, a form of reproduction in which an egg develops into an embryo without being fertilized by sperm, might be more common than you realized.Mercedes Burns, Assistant Professor of Biological Sciences, University of Maryland, Baltimore CountyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1454832020-11-04T14:43:16Z2020-11-04T14:43:16ZHow predators may have shaped the way some southern African lizards survive and reproduce<figure><img src="https://images.theconversation.com/files/368536/original/file-20201110-19-1eohqmk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A male Agama planiceps shows off his colouring on a rock in Namibia.</span> <span class="attribution"><span class="source">Ondrej Prosicky/Shutterstock</span></span></figcaption></figure><p>Fitness, the way the naturalist Charles Darwin <a href="https://www.darwinproject.ac.uk/letters/darwins-life-letters/darwin-letters1866-survival-fittest">conceptualised it</a>, refers to the ability of organisms to survive and reproduce successfully. Reproductive success lies in species’ ability to have offspring that are also capable of surviving and reproducing, as are their offspring and so on down the line of descent. </p>
<p>Species optimise their Darwinian fitness – and their long-term survival – differently. Both adults and offspring experience challenges to their survival in the environments where they occur and species have evolved strategies to deal with these environmental pressures. These evolutionary processes are driven by natural selection, which favours the individuals best equipped to survive and reproduce. Their numbers in the population increase with generations. The numbers of poorly equipped individuals decrease with generations. </p>
<p>One environmental pressure experienced by species in general is predation. By eliminating the less fit individuals over time, predation can drive the population to increasing fitness in terms of survival and reproductive success.</p>
<p>This is what seems to be the case in two species of reptile we <a href="https://www.tandfonline.com/doi/abs/10.1080/04416651.1993.9650368">studied</a> for several years in <a href="https://brill.com/view/journals/amre/15/4/article-p351_4.xml?language=en">Namibia</a>. The two species of southern African agamids (a family of lizards) have widely differing survival and reproductive strategies. The reason may lie with their predators.</p>
<h2>Different adaptations</h2>
<p>The first species, <em>Agama planiceps</em>, the larger of the two, is highly visible because of its colourful body. It lives in groups on rocky outcrops in savanna areas. Males aggressively defend territories during the reproductive season. During this time their head, throat and tail are bright orange red, and their body and legs shiny deep purple. Females do not undergo any changes to their normal yellow-spotted head and black body colouration. Each male defends a territory with at least two adult females along with several subadult males and females.</p>
<p><em>Agama aculeata</em>, on the other hand, is a solitary, well camouflaged species because of its body colour. It lives in flat, sandy savanna areas. Its males also defend territories, though less aggressively than <em>planiceps</em> males do. Males and females form monogamous breeding pairs. The head and throat of males turn deep blue, while females develop light blue head colouration and brown blotches on their trunk when carrying eggs.</p>
<p>Although many aspects of their biology are similar, the two agamid species have very different social behaviour and reproductive characteristics. We believe these differences most likely evolved in response to the differing levels of predation the species experienced. Based on their differences in body colour it can be deduced that they are not equally detectable to predators that hunt by sight, and should therefore differ with respect to the predation pressure they experience from them. In the area where the study was conducted, the yellow mongoose and rock kestrel were two such predators which hunted both species.</p>
<p>In lizards, damaged tails are a sign of predation – but also a successful escape. The percentage of damaged tails in the highly visible <em>Agama planiceps</em> was double that in the less visible <em>Agama aculeata</em>. This, in our view, indicates higher predation pressure in <em>Agama planiceps</em>.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/356303/original/file-20200903-22-yu3xfs.jpg?ixlib=rb-1.1.0&rect=714%2C938%2C1917%2C758&q=45&auto=format&w=1000&fit=clip"><img alt="A dully-coloured lizard emerges from a hole in the ground" src="https://images.theconversation.com/files/356303/original/file-20200903-22-yu3xfs.jpg?ixlib=rb-1.1.0&rect=714%2C938%2C1917%2C758&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/356303/original/file-20200903-22-yu3xfs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/356303/original/file-20200903-22-yu3xfs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/356303/original/file-20200903-22-yu3xfs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/356303/original/file-20200903-22-yu3xfs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/356303/original/file-20200903-22-yu3xfs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/356303/original/file-20200903-22-yu3xfs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A female Agama aculeata in Namibia.</span>
<span class="attribution"><span class="source">Provided by the author</span></span>
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</figure>
<p>The <em>planiceps</em> females are larger than their <em>aculeata</em> counterparts. But they carry on average only half the number of eggs. The total mass of its egg clutch as a percentage of its body mass was also about half the <em>aculeata</em>‘s. The eggs of <em>planiceps</em> are larger than <em>aculeata</em>’s; so are the newly hatched young. </p>
<p>So, what adaptive advantages do these differences give the two species in terms of coping with predation pressure and maximising their survival and reproductive success?</p>
<h2>What it all means</h2>
<p>In the case of the colourful <em>planiceps</em>, being social should give it the advantage of group vigilance and timely detection of predators. The camouflage and solitary behaviour of <em>aculeata</em>, meanwhile, should mean it’s harder for predators to detect. The larger size of <em>planiceps</em> males, females and hatchlings may also afford them greater running speed for escaping predatory attacks.</p>
<p>It is likely that <em>planiceps</em> maximises the survival prospects of male genes through their distribution among the eggs of several females. Females, in turn, should benefit from having offspring that carry the genes of strong and healthy males as well as living in well-resourced territories in terms of food (mainly insects) and shelter. </p>
<p>Monogamy in the solitary <em>aculeata</em>, on the other hand, should reduce detection by predators as the species moves less. This would maximise their survival. And the large number of offspring they produce should maximise their reproductive success.</p>
<p>The lighter egg clutch carried by a <em>planiceps</em> female may ensure that she can still run fast enough to escape predatory attacks. Bigger hatchlings may also be able to run faster to escape predators. The hatchlings remain in groups, which may give them the advantage of confusing predators by scattering in all directions during an attack.</p>
<p>Given the assumption that camouflage and solitary behaviour protect <em>aculeata</em> against predators rather than running speed, it is not surprising that females of this species, on average, carry a much heavier load of eggs than <em>planiceps</em> females. They are often so weighed down by their eggs that they are barely able to run. Their smaller and camouflaged hatchlings are also solitary and extremely hard to spot, even to the trained eye. They generally remain stationary and dash for cover only when approached too closely, which should serve them well in dealing with predators.</p>
<p>Given these findings regarding their social behaviour and reproductive characteristics, and the difference in damaged tails found between them, there’s a strong case that predation is what has shaped their strategies for survival and reproductive success.</p><img src="https://counter.theconversation.com/content/145483/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Neil Heideman received funding from the University of Stellenbosch. </span></em></p><p class="fine-print"><em><span>Joaquín Verdú Ricoy does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>By eliminating the less fit individuals over time, predation can drive the population to increasing fitness in terms of survival and reproductive success.Neil Heideman, Professor in Zoology, University of the Free StateLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1460202020-10-02T04:38:10Z2020-10-02T04:38:10ZPhotos from the field: Australia is full of lizards so I went bush to find out why<figure><img src="https://images.theconversation.com/files/361292/original/file-20201002-23-b49b1d.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C1800%2C1196&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A lace monitor (_Varanus varius_)</span> <span class="attribution"><span class="source">Kristian Bell</span>, <span class="license">Author provided</span></span></figcaption></figure><p><em>Environmental scientists see flora, fauna and phenomena the rest of us rarely do. In this new series, we’ve invited them to share their unique <a href="https://theconversation.com/au/topics/photos-from-the-field-92499">photos from the field</a>.</em></p>
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<p>Though it may not be as famous a stereotype as shrimps on the barbie, deadly snakes or Vegemite, Australia is renowned in certain scientific circles for being the “<a href="https://catalogue.nla.gov.au/Record/237306">land of the lizards</a>”. </p>
<p>Australia has a higher diversity of lizards than anywhere else in the world. The number of different species within a single part of remote, central Australia well exceeds similar desert environments, such as the Kalahari in Africa, or the US.</p>
<p>Over the last 50 years, scientists have tried to understand the cause of this extraordinary and unique diversity.</p>
<p>Some suggest unpredictable resources in the arid outback, such as sporadic rain, favour low-energy animals like lizards over birds and mammals. Others claim a high diversity of termites allows lots of different termite-eating lizards to <a href="https://idp.springer.com/authorize/casa?redirect_uri=https://link.springer.com/content/pdf/10.1007/BF00323768.pdf&casa_token=jd7gMnImVKEAAAAA:4xHkody7X4uMGA9WmaFIlQNOroVClmtKx3jmH5rPNWNA4aU4HS939cZZReB9zvKVHNhAk1yffhWh8Qzl">co-exist</a>. </p>
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Read more:
<a href="https://theconversation.com/new-research-reveals-these-20-australian-reptiles-are-set-to-disappear-by-2040-145385">New research reveals these 20 Australian reptiles are set to disappear by 2040</a>
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<p>Or perhaps the presence of shrubs, sparse trees and grass clumps provide a variety of niches (microhabitats) for tree and litter dwelling <a href="https://www.journals.uchicago.edu/doi/abs/10.1086/284847">species</a>. Despite these many hypotheses, no consensus has ever been reached.</p>
<p>My research explores the role of spinifex, a spiky clumping grass that’s typically found in the arid outback, often in conjunction with lizard diversity hotspots. </p>
<p>With many species found nowhere else on earth, some Australian lizards are threatened with <a href="https://theconversation.com/new-research-reveals-these-20-australian-reptiles-are-set-to-disappear-by-2040-145385">extinction</a>. Understanding how and why lizards use this iconic outback plant can help us conserve them, by predicting how they might respond to disturbances such as habitat loss and climate change.</p>
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Read more:
<a href="https://theconversation.com/spinifex-grass-would-like-us-to-stop-putting-out-bushfires-please-105651">Spinifex grass would like us to stop putting out bushfires, please</a>
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<p>Following many trips to the outback, I was surprised to find locals who had never encountered some of the species I was studying. Taking photographs of these often small and overlooked animals helps me to better engage the community and raise the wider public profile of lizards, compared to other, more “charismatic” native animals. </p>
<h2>A thriving desert ecosystem</h2>
<p>All <a href="http://www.theplantlist.org/">60 species of spinifex grasses</a> (members of the <em>Triodia</em> genus) are found only in Australia. Although spinifex habitats cover more than <a href="https://books.google.com.au/books?hl=en&lr=&id=4f8anIoS33MC&oi=fnd&pg=PA145&dq=Allan+GE,+Southgate+RI.+Fire+regimes+in+the+spinifex+landscapes+of+Australia.+In+%E2%80%98Flammable+Australia%E2%80%99.(Eds+RA+Bradstock,+JE+Williams,+AM+Gill)+pp.+145%E2%80%93176.+Cambridge+University+Press:+Cambridge,+UK%3B+2002&ots=kHblG0pZlh&sig=-pOdZ8f8uQ5y1hhHFG7HzfTUIbk#v=onepage&q&f=false">one-fifth of mainland Australia</a>, the plant is little-known and <a href="https://theconversation.com/spinifex-grass-would-like-us-to-stop-putting-out-bushfires-please-105651">little-loved</a> by non-naturalists.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/361247/original/file-20201002-18-1oackxs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Spinifex clumps on red dirt" src="https://images.theconversation.com/files/361247/original/file-20201002-18-1oackxs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/361247/original/file-20201002-18-1oackxs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/361247/original/file-20201002-18-1oackxs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/361247/original/file-20201002-18-1oackxs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/361247/original/file-20201002-18-1oackxs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/361247/original/file-20201002-18-1oackxs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/361247/original/file-20201002-18-1oackxs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A typical mallee ecosystem where we conduct our research, with plenty of spinifex clumps interspersed with the many-stemmed trunks, characteristic of mallee eucalypts.</span>
<span class="attribution"><span class="source">Kristian Bell</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Spinifex typically forms a spiky and impenetrable clump that provides useful, and in some cases essential, resources to <a href="https://onlinelibrary.wiley.com/doi/abs/10.1046/j.1442-9993.2001.01152.x">lizards</a>, <a href="https://www.sciencedirect.com/science/article/abs/pii/S0006320708004382">birds</a>, <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/aec.12323">mammals</a> and <a href="https://link.springer.com/article/10.1007/BF00172138">invertebrates</a>. </p>
<p>But despite the close association of many lizard species to spinifex, we still don’t know exactly why reptiles like it so much.</p>
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Read more:
<a href="https://theconversation.com/i-walked-1-200km-in-the-outback-to-track-huge-lizards-heres-why-130194">I walked 1,200km in the outback to track huge lizards. Here's why</a>
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<p>Three ideas dominate. First, spinifex may contain lots of food for lizards, such as <a href="https://books.google.com.au/books?hl=en&lr=&id=h4YrDgAAQBAJ&oi=fnd&pg=PP1&dq=Pianka+ER.+Ecology+and+natural+history+of+desert+lizards:+analyses+of+the+ecological+niche+and+community+structure.+Princeton,+New+Jersey:+Princeton+University+Press%3B+1986.+&ots=DS3Cop-u6I&sig=9M30nbmYgGuJ7inKvHbrfM9tAjw#v=onepage&q&f=false">termites or ants</a>. </p>
<p>Alternatively, the spiky, needle-like leaves of spinifex may offer small lizards a great place to hide from predators. And finally, temperatures deep within a dense spinifex hummock can be very cool compared to the searing desert heat, where temperatures can reach a scorching 50°C.</p>
<p>My research aim is to work out which, if any, of these explanations is true. I do this by measuring variables such as temperature, invertebrate abundance and risk of becoming prey, in spinifex and other plants. </p>
<p>Alongside my supervisors, I have also conducted behaviour trials on a couple of spinifex-loving lizard species: the mallee ctenotus (<em>Ctenotus atlas</em>) and the mallee dragon (<em>Ctenophorus spinodomus</em>).</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/361263/original/file-20201002-18-v3ktpa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/361263/original/file-20201002-18-v3ktpa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/361263/original/file-20201002-18-v3ktpa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=429&fit=crop&dpr=1 600w, https://images.theconversation.com/files/361263/original/file-20201002-18-v3ktpa.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=429&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/361263/original/file-20201002-18-v3ktpa.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=429&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/361263/original/file-20201002-18-v3ktpa.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=538&fit=crop&dpr=1 754w, https://images.theconversation.com/files/361263/original/file-20201002-18-v3ktpa.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=538&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/361263/original/file-20201002-18-v3ktpa.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=538&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Setting up behavioural trial enclosures. After more than 100,000 recorded observations, we are only beginning to better understand why lizards like using spinifex.</span>
<span class="attribution"><span class="source">Kristian Bell</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>We have recorded 230,000 temperatures, caught 16,089 invertebrates, constructed 112 lizard models and classified 143,627 behavioural observations. But such is the complicated nature of the work, we’re only partially closer to understanding the lizard-spinifex relationship. So far, our data suggests temperature is a key component.</p>
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Read more:
<a href="https://theconversation.com/does-australia-really-have-the-deadliest-snakes-we-debunk-6-common-myths-145765">Does Australia really have the deadliest snakes? We debunk 6 common myths</a>
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<p>The photos below are generally a result of good fortune and spending inordinate amounts of time in wild places. Pictures of some of the smaller, more skittish animals were taken upon release from pitfall traps.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/361250/original/file-20201002-18-tcxw3b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A close-up of mallee ctenotus, a striped lizard" src="https://images.theconversation.com/files/361250/original/file-20201002-18-tcxw3b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/361250/original/file-20201002-18-tcxw3b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/361250/original/file-20201002-18-tcxw3b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/361250/original/file-20201002-18-tcxw3b.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/361250/original/file-20201002-18-tcxw3b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/361250/original/file-20201002-18-tcxw3b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/361250/original/file-20201002-18-tcxw3b.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Mallee ctenotus (<em>Ctenotus atlas</em>)</span>
<span class="attribution"><span class="source">Kristian Bell</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/361252/original/file-20201002-13-1f7y43x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A profile of a mallee dragon" src="https://images.theconversation.com/files/361252/original/file-20201002-13-1f7y43x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/361252/original/file-20201002-13-1f7y43x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=429&fit=crop&dpr=1 600w, https://images.theconversation.com/files/361252/original/file-20201002-13-1f7y43x.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=429&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/361252/original/file-20201002-13-1f7y43x.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=429&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/361252/original/file-20201002-13-1f7y43x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=538&fit=crop&dpr=1 754w, https://images.theconversation.com/files/361252/original/file-20201002-13-1f7y43x.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=538&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/361252/original/file-20201002-13-1f7y43x.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=538&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Mallee dragon (<em>Ctenophorus spinodomus</em>)</span>
<span class="attribution"><span class="source">Kristian Bell</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The above two photos show my study species: the mallee dragon and the mallee ctenotus. Despite one lizard being a skink and the other a dragon, both species are strongly associated with spinifex. The skink tends to forage within spinifex, whereas the dragon emerges into open patches adjacent to spinifex to eat and “signal” to other dragons. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/361248/original/file-20201002-18-1l9zyc1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Spinifex with a rainbow in the background" src="https://images.theconversation.com/files/361248/original/file-20201002-18-1l9zyc1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/361248/original/file-20201002-18-1l9zyc1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/361248/original/file-20201002-18-1l9zyc1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/361248/original/file-20201002-18-1l9zyc1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/361248/original/file-20201002-18-1l9zyc1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/361248/original/file-20201002-18-1l9zyc1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/361248/original/file-20201002-18-1l9zyc1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption"></span>
<span class="attribution"><span class="source">Kristian Bell</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Spinifex grass, pictured above, with its spiky, needle-like leaves, creates valuable habitat for numerous species of birds, mammals and invertebrates — not just reptiles. Its abundance and influence on many species make it a “<a href="https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/1365-2745.12768">foundation species</a>”.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/361253/original/file-20201002-17-3j7bbg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Burton's legless lizard" src="https://images.theconversation.com/files/361253/original/file-20201002-17-3j7bbg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/361253/original/file-20201002-17-3j7bbg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/361253/original/file-20201002-17-3j7bbg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/361253/original/file-20201002-17-3j7bbg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/361253/original/file-20201002-17-3j7bbg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/361253/original/file-20201002-17-3j7bbg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/361253/original/file-20201002-17-3j7bbg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Burton’s legless lizard (<em>Lialis burtonis</em>)</span>
<span class="attribution"><span class="source">Kristian Bell</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>This photo above shows a Burton’s legless lizard (<em>Lialis burtonis</em>) — a predator of my study species. These <a href="https://blogs.ucl.ac.uk/museums/2016/07/15/whats-the-difference-between-snakes-and-legless-lizards/">snake-like reptiles</a> are specialist lizard hunters and often use the dense cover of spinifex to their advantage to ambush passing lizards. </p>
<p>Legless lizards might look a bit like snakes, but they have different ancestries and subtle distinguishing features, such as the lizard’s eyelids and external ears, which snakes don’t have. </p>
<p>But many other animals live in or near spinifex, and would happily make a meal of small lizards, including those shown in the following photos. The ability of numerous predators to access the centre of spiky spinifex clumps throws some doubt on the idea spinifex is used as protection from predators.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/361258/original/file-20201002-23-kc7cq4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="slender-tailed dunnart" src="https://images.theconversation.com/files/361258/original/file-20201002-23-kc7cq4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/361258/original/file-20201002-23-kc7cq4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/361258/original/file-20201002-23-kc7cq4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/361258/original/file-20201002-23-kc7cq4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/361258/original/file-20201002-23-kc7cq4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/361258/original/file-20201002-23-kc7cq4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/361258/original/file-20201002-23-kc7cq4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Slender-tailed dunnart (<em>Sminthopsis murina</em>)</span>
<span class="attribution"><span class="source">Kristian Bell</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/361259/original/file-20201002-15-1mku3wx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A soaring black shouldered kite" src="https://images.theconversation.com/files/361259/original/file-20201002-15-1mku3wx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/361259/original/file-20201002-15-1mku3wx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=480&fit=crop&dpr=1 600w, https://images.theconversation.com/files/361259/original/file-20201002-15-1mku3wx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=480&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/361259/original/file-20201002-15-1mku3wx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=480&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/361259/original/file-20201002-15-1mku3wx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=603&fit=crop&dpr=1 754w, https://images.theconversation.com/files/361259/original/file-20201002-15-1mku3wx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=603&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/361259/original/file-20201002-15-1mku3wx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=603&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Black shouldered kite (<em>Elanus axillaris</em>)</span>
<span class="attribution"><span class="source">Kristian Bell</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/361260/original/file-20201002-14-1do2fav.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Dwyers snake, with a researcher in the background" src="https://images.theconversation.com/files/361260/original/file-20201002-14-1do2fav.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/361260/original/file-20201002-14-1do2fav.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/361260/original/file-20201002-14-1do2fav.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/361260/original/file-20201002-14-1do2fav.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/361260/original/file-20201002-14-1do2fav.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/361260/original/file-20201002-14-1do2fav.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/361260/original/file-20201002-14-1do2fav.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Dwyers snake.</span>
<span class="attribution"><span class="source">Kristian Bell</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/361262/original/file-20201002-16-1cmvml.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Sand monitor" src="https://images.theconversation.com/files/361262/original/file-20201002-16-1cmvml.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/361262/original/file-20201002-16-1cmvml.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/361262/original/file-20201002-16-1cmvml.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/361262/original/file-20201002-16-1cmvml.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/361262/original/file-20201002-16-1cmvml.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/361262/original/file-20201002-16-1cmvml.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/361262/original/file-20201002-16-1cmvml.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Sand monitor.</span>
<span class="attribution"><span class="source">Kristian Bell</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>We can’t claim to have cracked the case yet. But we’re a step closer to unravelling the secrets behind one of Australia’s remarkable, and under-appreciated, biodiversity stories. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/scientists-capture-rare-footage-of-mother-skink-fighting-a-deadly-brown-snake-to-protect-her-babies-145530">Scientists capture rare footage of mother skink fighting a deadly brown snake to protect her babies</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/146020/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kristian Bell receives funding from the Hermon Slade Foundation and Deakin University’s Centre for Integrative Ecology.</span></em></p>Australia is known as the ‘land of the lizards’. These photos show why they deserve more of your attention.Kristian Bell, PhD candidate, Deakin UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1471222020-09-29T15:06:06Z2020-09-29T15:06:06ZReptiles: one in three species traded online – and 75% aren’t protected by international law<p>Rhinos, tigers, pangolins – we’re used to hearing about the mammals that are snatched from the wild so that their body parts can be sold. But did you know that you can buy and sell 36% of all known reptile species over the internet? That’s more than one in three species, including the endangered <a href="http://speciesstatus.sanbi.org/assessment/last-assessment/43/">speckled tortoise</a> (the world’s smallest species of tortoise) and the <a href="http://reptile-database.reptarium.cz/species?genus=Archaius&species=tigris">Seychelles tiger chameleon</a>. </p>
<p>Reptiles are consistently overlooked by trade regulations. The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) is the world’s mechanism for protecting wildlife in global markets. This global agreement is supposed to regulate the trade of species to prevent them being overexploited, but <a href="https://www.nature.com/articles/s41467-020-18523-4">a new study</a> has revealed that more than 75% of reptiles traded online are species that are not covered by CITES. And as the online trade has grown, even reptiles protected by CITES are being taken from their natural habitats and sold to buyers around the world.</p>
<p>Reptiles are mostly traded for two reasons. In the fashion industry, their skins are made into leather. Reptile skins are what CITES mostly records, as this trade happens on a commercial scale. Thousands of skins of crocodiles, in particular, but lizards and snakes too, are shipped around the world to make boots, purses, and watch straps among other things. Much less well documented, according to the new study, which I have also found in my <a href="https://www.crimejusticejournal.com/article/view/1243/805">own research</a>, is the smaller scale trade in individual reptiles for “personal” use, like the pet trade.</p>
<figure class="align-center ">
<img alt="A woman wearing a fur coat holds a brown crocodile skin handbag." src="https://images.theconversation.com/files/360536/original/file-20200929-18-oacw5i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/360536/original/file-20200929-18-oacw5i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/360536/original/file-20200929-18-oacw5i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/360536/original/file-20200929-18-oacw5i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/360536/original/file-20200929-18-oacw5i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/360536/original/file-20200929-18-oacw5i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/360536/original/file-20200929-18-oacw5i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Reptile skin is commonly used in expensive luxury goods, like designer handbags.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/milan-february-21-woman-hermes-brown-1055313779">Andersphoto/Shutterstock</a></span>
</figcaption>
</figure>
<h2>Scaling back the trade</h2>
<p>At first, it may not seem that the sale of one reptile here and there presents a problem. But the wildlife trade is a global phenomenon. The tens, if not hundreds of thousands of individual sales of reptiles taking place around the world every year add up. The result is that small populations of reptiles – some of which only live in one particular place – are threatened with extinction. The demand for rare and unique companion animals helps fuel this.</p>
<p>Farming reptiles, or breeding them in captivity, is often touted as a solution, but this approach has its own problems. </p>
<p>Captive breeding has been a source of illegal activity in the past. Businesses that were supposedly breeding reptiles in large quantities to meet demand were found to likely have been taking them <a href="https://www.traffic.org/site/assets/files/6060/adding-up-the-numbers.pdf">from the wild instead</a>. This kind of laundering is difficult to control unless there are robust practices in place to trace reptiles all the way from source to final purchase.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/captive-breeding-has-a-dark-side-as-disturbing-czech-discovery-of-trafficked-tiger-body-parts-highlights-107371">Captive breeding has a dark side – as disturbing Czech discovery of trafficked tiger body parts highlights</a>
</strong>
</em>
</p>
<hr>
<p>Captive breeding in the reptile trade also has horrible consequences for animal welfare. As colleagues and I have <a href="https://www.crimejusticejournal.com/article/view/1243/805">argued</a>, the reptile leather industry is extraordinarily cruel. Animals are often kept in unhygienic conditions and slaughter is usually done while the reptile is conscious. That means many animals are skinned while still alive.</p>
<p>The pet industry is little better. Reptiles are crammed into small boxes and flown as cargo all over the world, enduring days without food and water and in fluctuating temperatures. There is no guarantee that they will be better kept once they arrive at their new home. </p>
<p>The biggest demand for pet reptiles is in Europe and North America. This is an important and often overlooked point: advertising the harm that the exotic pet trade causes could help reduce demand where it is greatest.</p>
<figure class="align-center ">
<img alt="Baby terrapins scramble over each other in a shallow tub." src="https://images.theconversation.com/files/360540/original/file-20200929-20-tuyjll.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/360540/original/file-20200929-20-tuyjll.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/360540/original/file-20200929-20-tuyjll.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/360540/original/file-20200929-20-tuyjll.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/360540/original/file-20200929-20-tuyjll.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/360540/original/file-20200929-20-tuyjll.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/360540/original/file-20200929-20-tuyjll.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Reptiles are flown thousands of miles to homes where they may be mistreated.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/small-tortoises-on-pet-market-above-1723341676">Dogora Sun/Shutterstock</a></span>
</figcaption>
</figure>
<p>The new research illuminates some of the areas where our understanding is most limited. We known that many reptiles are sold as ingredients in medicines for example, but we know almost nothing about the scale of this trade. This requires investigation, as does the role of social media – including Facebook and WhatsApp – in supporting the buying and selling of reptiles and other wildlife. </p>
<p>The new study also raises an alternative to the way the wildlife trade is currently regulated. What if no trade was the default starting point? Trade would only take place if there was sufficient evidence to show that it would not harm the survival of the species. This precautionary approach would address the lack of data for many species and also potentially simplify customs checks. </p>
<p>It’s time to rethink how this trade is regulated, and our relationship to wildlife altogether.</p><img src="https://counter.theconversation.com/content/147122/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tanya Wyatt receives funding from the Scottish Government. She has received funding in the past from the Arts and Humanities Research Council. </span></em></p>Reptiles are consistently overlooked by regulators of the trade in wildlife, but many face extinction in the wild.Tanya Wyatt, Professor of Criminology, Northumbria University, NewcastleLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1455302020-09-03T02:56:37Z2020-09-03T02:56:37ZScientists capture rare footage of mother skink fighting a deadly brown snake to protect her babies<figure><img src="https://images.theconversation.com/files/356213/original/file-20200903-18-hmj7hb.jpeg?ixlib=rb-1.1.0&rect=232%2C0%2C1149%2C745&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Author provided</span></span></figcaption></figure><p>Unlike many mammals and birds, most reptiles show little sign of being caring parents. But our new research shows one lizard species may be more doting parents than we thought – the adults risking their own safety to protect their babies.</p>
<p>We used cameras in the Snowy Mountains of New South Wales to study the Cunningham’s skink. We were surprised to record evidence of the lizards actively defending their newborn offspring against formidable predators. Our findings are outlined in a <a href="https://www.publish.csiro.au/ZO/ZO20024">paper</a> released today.</p>
<p>Most startlingly, we recorded a mother skink aggressively attacking a large, deadly brown snake while her babies watched on. We also witnessed 12 incidents of skinks chasing magpies away from their young.</p>
<p>We originally set out to record how species such as skinks will cope with climate change. But this evolved into a study of the fascinating and surprising social bonds between lizard offspring and their parents.</p>
<figure class="align-center ">
<img alt="Adult and young skinks sun-baking together" src="https://images.theconversation.com/files/356215/original/file-20200903-22-jmpjnk.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/356215/original/file-20200903-22-jmpjnk.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=380&fit=crop&dpr=1 600w, https://images.theconversation.com/files/356215/original/file-20200903-22-jmpjnk.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=380&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/356215/original/file-20200903-22-jmpjnk.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=380&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/356215/original/file-20200903-22-jmpjnk.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=477&fit=crop&dpr=1 754w, https://images.theconversation.com/files/356215/original/file-20200903-22-jmpjnk.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=477&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/356215/original/file-20200903-22-jmpjnk.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=477&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Sun-loving skinks live together in social groups.</span>
<span class="attribution"><span class="source">Authors provided</span></span>
</figcaption>
</figure>
<h2>What is the Cunningham’s skink?</h2>
<p>The Cunningham’s skink (<em>Egernia cunninghami</em>) is a large, sun-loving, spiny lizard native to southeast Australia. It’s <a href="https://australian.museum/learn/animals/reptiles/cunninghams-skink/">named after</a> Alan Cunningham, an explorer who collected the first specimen in the Blue Mountains.</p>
<p>The skinks are active during the day. They feed on invertebrates such as insects, snails and slugs, as well as vegetation.</p>
<p>The Cunningham’s skink lives in social groups – a behaviour very rare among lizards and reptiles. In these groups, mothers give birth to live young (rather than eggs) then live alongside their kids, sometimes for several years.</p>
<p>The species has strength in numbers – living in a group makes it easier to spot threats, which helps the group survive.</p>
<figure class="align-center ">
<img alt="Adult and young skinks sun-baking together" src="https://images.theconversation.com/files/356175/original/file-20200903-18-1sih2ic.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/356175/original/file-20200903-18-1sih2ic.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/356175/original/file-20200903-18-1sih2ic.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/356175/original/file-20200903-18-1sih2ic.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/356175/original/file-20200903-18-1sih2ic.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/356175/original/file-20200903-18-1sih2ic.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/356175/original/file-20200903-18-1sih2ic.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Thew offspring of Cunningham’s skinks can stay with the parents for several years.</span>
</figcaption>
</figure>
<h2>The mother of all discoveries</h2>
<p>Using video and thermal imaging, we observed the skinks on 32 days over three years.</p>
<p>Among reptiles, evidence of parental protection in their natural environment has been rare and typically anecdotal. We witnessed four birthing sessions, and then monitored skink encounters in the presence of their offspring.</p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/new-research-reveals-these-20-australian-reptiles-are-set-to-disappear-by-2040-145385">New research reveals these 20 Australian reptiles are set to disappear by 2040</a>
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<p>Videoing nature can be tricky. Often, the action takes place away from where you’ve directed your camera. So when we saw a snake, it was a scramble to get a free video camera and start recording. </p>
<p>We witnessed two separate encounters with an eastern brown snake. The first involved the snake sneaking up on six-day-old skinks basking in the sun (see footage below). We recorded the mother running towards the predator and biting it for several seconds. The snake writhes around before the mother releases her grip and returns unharmed to her young.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/6qhw0urfHRY?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
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<p>The following year, we encountered two adult skinks attacking another eastern brown snake in bushes. Juvenile skinks were nearby. The skinks bit tight to the snake’s body, and the snake dragged them for more than 15 metres before the skinks released their grip. </p>
<p>Snakes were not the only predator vanquished by the protective skink parents – Cunningham’s skinks regularly chased magpies away from their young. We observed 12 encounters between skinks and magpies. In each case, an adult skink aggressively chased and/or attacked the magpie after the bird came close to the group. </p>
<figure class="align-center ">
<img alt="Thermal camera image showing the mother skink attacking the snake while her babies watch on" src="https://images.theconversation.com/files/356173/original/file-20200903-18-1ggaglv.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/356173/original/file-20200903-18-1ggaglv.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=322&fit=crop&dpr=1 600w, https://images.theconversation.com/files/356173/original/file-20200903-18-1ggaglv.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=322&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/356173/original/file-20200903-18-1ggaglv.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=322&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/356173/original/file-20200903-18-1ggaglv.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=405&fit=crop&dpr=1 754w, https://images.theconversation.com/files/356173/original/file-20200903-18-1ggaglv.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=405&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/356173/original/file-20200903-18-1ggaglv.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=405&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Thermal camera image showing the mother skink attacking the snake while her babies watch on.</span>
</figcaption>
</figure>
<h2>What does this all mean?</h2>
<p>Some animals rarely interact with others of the same species, even their offspring. In fact, available data suggests infanticide – where mature animals kill young offspring of the same species – can occur among some skink species. </p>
<p>We saw no such behaviour among the Cunningham’s skink, or aggression towards each other.</p>
<p>While the aggression of the adult skinks towards predators took place in the presence of young, the adults may have been exhibiting self-defence or territorial behaviour. Regardless, the attacks on predators in the presence of newborns does reflect parental care, either directly or indirectly. Our future field excursions will hopefully shed more light on this.</p>
<p>Understanding the factors that bring parents and offspring together, and keep them together, is important in our broader understanding of <a href="https://www.nature.com/subjects/social-evolution">social evolution</a> – that is, how social interactions of species arise, change and are maintained.</p>
<p>It will also help us understand how animals cooperating with and caring for each other can benefit both the individual, and the whole.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/a-few-months-ago-science-gave-this-rare-lizard-a-name-and-it-may-already-be-headed-for-extinction-140356">A few months ago, science gave this rare lizard a name – and it may already be headed for extinction</a>
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<img src="https://counter.theconversation.com/content/145530/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Some skinks have been known to kill their babies – but one remarkable species goes to any lengths to save them.Gregory Watson, Senior Lecturer, Science, University of the Sunshine CoastJolanta Watson, Lecturer in Science, University of the Sunshine CoastLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1453852020-09-02T19:58:41Z2020-09-02T19:58:41ZNew research reveals these 20 Australian reptiles are set to disappear by 2040<figure><img src="https://images.theconversation.com/files/355975/original/file-20200902-14-1yoende.jpg?ixlib=rb-1.1.0&rect=10%2C14%2C1187%2C783&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Cape Melville leaf-tailed gecko </span> <span class="attribution"><span class="source">Conrad Hoskin</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Action came too late for the Christmas Island forest skink, despite early warnings of significant declines. It was lost from the wild before it was officially listed as “threatened”, and the few individuals brought into captivity <a href="https://conbio.onlinelibrary.wiley.com/doi/full/10.1111/cobi.12852">died soon after</a>. </p>
<p>Australia is home to about 10% of all known reptile species — the largest number of any country in the world. But many of our <a href="https://doi.org/10.1016/j.biocon.2019.108203">reptiles are at risk of the same fate</a> as the Christmas Island forest skink: extinction.</p>
<p>In <a href="https://doi.org/10.1071/PC20033">new research published today</a>, we identified the 20 terrestrial snakes and lizards (collectively known as “squamates”) at greatest risk of extinction in the next two decades, assuming no changes to current conservation management. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/ZjwfD_4uT-k?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Preventing extinctions of Australian lizards and snakes.</span></figcaption>
</figure>
<p>While all 20 species meet international criteria to be officially listed as “threatened”, only half are protected under Australian environmental legislation— the <a href="https://www.environment.gov.au/epbc/about">Environment Protection and Biodiversity Conservation (EPBC) Act</a>. This needs urgent review.</p>
<p>Many of these reptiles receive little conservation action, but most of their threats can be ameliorated. By identifying the species at greatest risk of extinction, we can better prioritise our recovery efforts — we know now what will be lost if we don’t act. </p>
<h2>Six species more likely than not to go extinct</h2>
<p>Our research team — including 27 reptile experts from universities, zoos, museums and government organisations across the country — identified six species with greater than 50% likelihood of extinction by 2040. </p>
<p>This includes two dragons, one blind snake and three skinks. Experts rated many others as having a 30-50% likelihood of extinction over the next 20 years.</p>
<p><iframe id="MiNhm" class="tc-infographic-datawrapper" src="https://datawrapper.dwcdn.net/MiNhm/3/" height="400px" width="100%" style="border: none" frameborder="0"></iframe></p>
<p>More than half (55%) of the 20 species at greatest risk occur in Queensland. Three live on islands: two on Christmas Island and one on Lancelin Island off the Western Australian coast. </p>
<p>Two more species are found in Western Australia, while the Northern Territory, the Australian Capital Territory, Victoria and New South Wales each have one species. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/australias-smallest-fish-among-22-at-risk-of-extinction-within-two-decades-144115">Australia's smallest fish among 22 at risk of extinction within two decades</a>
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<p>Each of the 20 species at greatest risk occur in a relatively small area, which partly explains the Queensland cluster — many species in that state naturally have very small distributions. </p>
<p>Most of the top 20 occupy a total range of fewer than 20 square kilometres, so could be lost to a single catastrophic event, such as a <a href="https://theconversation.com/click-through-the-tragic-stories-of-119-species-still-struggling-after-black-summer-in-this-interactive-and-how-to-help-131025">large bushfire</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/355910/original/file-20200901-16-12tl1t0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A map of Australia showing where the 20 snakes and lizards are located" src="https://images.theconversation.com/files/355910/original/file-20200901-16-12tl1t0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/355910/original/file-20200901-16-12tl1t0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=445&fit=crop&dpr=1 600w, https://images.theconversation.com/files/355910/original/file-20200901-16-12tl1t0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=445&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/355910/original/file-20200901-16-12tl1t0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=445&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/355910/original/file-20200901-16-12tl1t0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=560&fit=crop&dpr=1 754w, https://images.theconversation.com/files/355910/original/file-20200901-16-12tl1t0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=560&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/355910/original/file-20200901-16-12tl1t0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=560&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The approximate locations of the 20 terrestrial snakes and lizards at greatest risk of extinction.</span>
<span class="attribution"><span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>So why are they dying out?</h2>
<p>Reptile species are declining on a global scale, and this is likely <a href="https://doi.org/10.1126/science.1190374">exacerbated by climate change</a>. In Australia, where more than 90% of our species occur nowhere else in the world, the most threatened reptiles are at risk for two main reasons: they have very small distributions, and ongoing, unmitigated threats. </p>
<p>The Cape Melville leaf-tailed gecko meets this brief perfectly. This large and spectacular species was only <a href="https://www.biotaxa.org/Zootaxa/article/view/zootaxa.3717.4.6/0">discovered in 2013</a>, on a remote mountain range on Cape York. It’s threatened by virtue of its very small distribution and population size, and by climate change warming and drying its upland habitat. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/355909/original/file-20200901-20-nk1cub.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Arnhem Land gorges skink" src="https://images.theconversation.com/files/355909/original/file-20200901-20-nk1cub.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/355909/original/file-20200901-20-nk1cub.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/355909/original/file-20200901-20-nk1cub.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/355909/original/file-20200901-20-nk1cub.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/355909/original/file-20200901-20-nk1cub.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/355909/original/file-20200901-20-nk1cub.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/355909/original/file-20200901-20-nk1cub.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The Arnhem Land gorges skink is considered more likely than not to become extinct by 2040. Threats include changes to food resources and habitat quality, feral cats, and possibly poisoning by cane toads.</span>
<span class="attribution"><span class="source">Chris Jolly</span></span>
</figcaption>
</figure>
<p>Habitat loss is also a major threat for the top 20 species. Australia’s most imperilled reptile, the <a href="http://www.environment.gov.au/biodiversity/threatened/recovery-plans/national-recovery-plan-grassland-earless-dragon-tympanocryptis-pinguicolla#:%7E:text=The%20Grassland%20Earless%20Dragon%20(Tympanocryptis%20pinguicolla)%20is%20a%20specialist%20inhabitant,the%20southern%20highlands%20of%20NSW%20.">Victoria grassland earless dragon</a>, used to be relatively common in grasslands in and around Melbourne. But the grasslands this little dragon once called home have been extensively cleared for agriculture and urban development, and now cover less than 1% of their original extent. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/click-through-the-tragic-stories-of-119-species-still-struggling-after-black-summer-in-this-interactive-and-how-to-help-131025">Click through the tragic stories of 119 species still struggling after Black Summer in this interactive (and how to help)</a>
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<h2>Little conservation attention</h2>
<p>For most reptile species, there has been less conservation work to address the declines, partly because reptiles have historically received less scientific attention than birds or mammals.</p>
<p>We also still don’t fully understand just how many species there are in Australia. <a href="https://doi.org/10.1111/jzo.12356">New reptile species</a> are being scientifically described at an average rate of 15 per year (a higher rate than for other vertebrate groups) and many new reptiles are already vulnerable to extinction at the time of discovery. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/355911/original/file-20200901-18-ibgyey.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="The Mount Surprise slider, a light-brown snake" src="https://images.theconversation.com/files/355911/original/file-20200901-18-ibgyey.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/355911/original/file-20200901-18-ibgyey.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/355911/original/file-20200901-18-ibgyey.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/355911/original/file-20200901-18-ibgyey.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/355911/original/file-20200901-18-ibgyey.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/355911/original/file-20200901-18-ibgyey.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/355911/original/file-20200901-18-ibgyey.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The Mount Surprise slider is threatened by invasive plant species and cattle compacting sandy soils.</span>
<span class="attribution"><span class="source">Stephen Zozaya</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>To make matters worse, <a href="https://doi.org/10.1016/j.biocon.2019.04.023">few reptiles in Australia are well-monitored</a>. Without adequate monitoring, we have a poor understanding of population trends and the impacts of threats. This means species could slip into extinction unnoticed. </p>
<p>Reptiles also lack the public and political profile that helps generate recovery support for other, (arguably) more charismatic Australian threatened animals — such as koalas and swift parrots — leading to little resourcing for conservation. </p>
<h2>Lessons from the past</h2>
<p>Only one Australian reptile, the Christmas Island forest skink, is officially listed as extinct, but we have most probably lost others before knowing they exist. Without increased resourcing and management intervention, many more Australian reptiles could follow the same trajectory. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/355913/original/file-20200901-20-vxjg1x.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="The Roma earless dragon sitting up on hind legs." src="https://images.theconversation.com/files/355913/original/file-20200901-20-vxjg1x.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/355913/original/file-20200901-20-vxjg1x.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=461&fit=crop&dpr=1 600w, https://images.theconversation.com/files/355913/original/file-20200901-20-vxjg1x.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=461&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/355913/original/file-20200901-20-vxjg1x.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=461&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/355913/original/file-20200901-20-vxjg1x.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=579&fit=crop&dpr=1 754w, https://images.theconversation.com/files/355913/original/file-20200901-20-vxjg1x.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=579&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/355913/original/file-20200901-20-vxjg1x.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=579&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Habitat loss and degradation due to agriculture is a major threat to the Roma earless dragon. It has not been listed under Australian legislation.</span>
<span class="attribution"><span class="source">A. O’Grady Museums Victoria</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>But it’s not all bad news. The pygmy bluetongue skink was once thought to be extinct until a <a href="https://www.youtube.com/watch?v=kEjQjeBrj0M">chance discovery</a> kick-started a long conservation and research program. </p>
<p>Animals are now being taken from the wild and relocated to new areas to establish more populations, signifying that positive outcomes are possible when informed by good science. </p>
<p>And the very restricted distributions of most of the species identified here should allow for targeted and effective recovery efforts. </p>
<p>By <a href="https://www.nespthreatenedspecies.edu.au/2.1%20Reptile%20red%20hot%20list%20findings%20factsheet_v4.pdf">identifying the species at greatest risk</a>, we hope to give governments, conservation groups and the community time to act to prevent further extinctions before it’s too late. Neglect should no longer be the default response for our fabulous reptile fauna.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/a-hidden-toll-australias-cats-kill-almost-650-million-reptiles-a-year-98854">A hidden toll: Australia's cats kill almost 650 million reptiles a year</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/145385/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Hayley Geyle receives funding from the National Environmental Science Program through the Threatened Species Recovery Hub. A group of 28 experts contributed to this research, but we would like to specifically acknowledge the contributions of the following people to this article: Hal Cogger, Jaana Dielenberg, Don Driscoll, Mike Gardner, Stephen Garnett, Matt Greenlees, Conrad Hoskin, Jane Melville, Damian Michael, Nicki Mitchell, Reid Tingley, Erik Wapstra and John Woinarski.</span></em></p><p class="fine-print"><em><span>David Chapple receives funding from the Australian Research Council. David is the Chair of the IUCN SSC Skink Specialist Group. </span></em></p>With targeted conservation action, we might just save many of these species before it’s too late.Hayley Geyle, Research Assistant, Charles Darwin UniversityDavid Chapple, Associate Professor in Evolutionary and Conservation Ecology, Monash UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1360952020-05-11T11:51:20Z2020-05-11T11:51:20ZYou’re not going far from home – and neither are the animals you spy out your window<figure><img src="https://images.theconversation.com/files/333732/original/file-20200508-49569-1qndzcw.jpg?ixlib=rb-1.1.0&rect=1109%2C1064%2C4186%2C2907&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Is it that same busy squirrel you're watching every day?</span> <span class="attribution"><span class="source">Julian Avery</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>Watching the wildlife outside your window can <a href="https://doi.org/10.3390/ijerph10030913">boost your mental well-being</a>, and it’s something lots of people have been doing a lot more of lately.</p>
<p>Maybe you’ve been wondering if you’re seeing one persistent gray squirrel or a rotating cast of furry characters. Maybe you’ve been thinking about which birds are passing through for the season and which are townies who stick around all year.</p>
<p><a href="https://scholar.google.com/citations?user=uYWmAHMAAAAJ&hl=en">As a wildlife ecologist</a>, I’ve learned to pay attention to patterns that show me what the animals outside my window are up to, and I usually know which individuals are my regulars.</p>
<p>Whether you’re spying on animals in a city, town or rural area, with a little background knowledge, you too can keep tabs on the private lives of your neighborhood critters.</p>
<h2>Seasonal shifts change the players</h2>
<p>For many species, winter is a time when individuals compete less with one another and gather in large groups.</p>
<p>For example, eastern cottontail rabbits congregate around areas with <a href="https://jhupbooks.press.jhu.edu/title/wild-mammals-north-america">plenty of food and places to escape to</a>. Birds form large mixed-species flocks, which helps them better find food and avoid being hunted. They even form temporary allegiances as they forage together, <a href="https://doi.org/10.1155/2011/670548">following specific individuals</a> who help determine where the flock goes.</p>
<figure>
<img src="https://cdn.theconversation.com/static_files/files/1027/whtspa-abundance-map-weekly-2019-760-4fps.gif?1588599297">
<figcaption><span class="caption">Seasonal migration means the abundance of particular species in one location can change over the course of the year. <i>Courtesy eBird.org (https://ebird.org/science/status-and-trends/whtspa/abundance-map-weekly)</i></span></figcaption>
</figure>
<p>As the season changes to spring, migratory species start arriving. A steady parade of individuals moves through the neighborhood. As animals transition to their breeding season, plumage and appearances may change as they work to attract mates. For many species, <a href="https://www.sibleyguides.com/about/the-sibley-guide-to-bird-life-behavior/">defense of a piece of land</a> becomes an overriding concern.</p>
<p>During the summer months, adult animal numbers stabilize, and the drive to establish a territory means you’re likely to have the same individuals active outside your windows for the majority of summer.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/333489/original/file-20200507-49556-1kpi6se.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/333489/original/file-20200507-49556-1kpi6se.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/333489/original/file-20200507-49556-1kpi6se.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=476&fit=crop&dpr=1 600w, https://images.theconversation.com/files/333489/original/file-20200507-49556-1kpi6se.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=476&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/333489/original/file-20200507-49556-1kpi6se.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=476&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/333489/original/file-20200507-49556-1kpi6se.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=599&fit=crop&dpr=1 754w, https://images.theconversation.com/files/333489/original/file-20200507-49556-1kpi6se.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=599&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/333489/original/file-20200507-49556-1kpi6se.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=599&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">This white-throated sparrow is molting into breeding plumage before heading on to summer grounds.</span>
<span class="attribution"><a class="source" href="https://www.instagram.com/p/B_YBazIADuM/">Julian Avery</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Splitting up the neighborhood</h2>
<p>A territory is a chunk of habitat. Its size will vary depending on the amount of food and breeding resources it holds. A territory with few trees, for example, may need to be bigger to hold enough forage for the animal that owns the turf.</p>
<p><a href="https://doi.org/10.1016/j.anbehav.2003.08.023">Territory sizes for different species</a> can range from the size of a large kitchen table (common <a href="https://doi.org/10.1016/j.zool.2007.04.001">lizards</a> like green anoles and skinks) to an area greater than 120 football fields (<a href="https://doi.org/10.1676/0043-5643(2000)112%5B0021:HRCOMC%5D2.0.CO;2">a raptor such as the Cooper’s hawk</a>). The cool thing is that <a href="https://jhupbooks.press.jhu.edu/title/wild-mammals-north-america">animal home ranges</a> are governed by their own needs and often do not follow the lines of human fences and alleyways.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/332882/original/file-20200505-83740-etd1qe.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/332882/original/file-20200505-83740-etd1qe.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/332882/original/file-20200505-83740-etd1qe.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=459&fit=crop&dpr=1 600w, https://images.theconversation.com/files/332882/original/file-20200505-83740-etd1qe.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=459&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/332882/original/file-20200505-83740-etd1qe.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=459&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/332882/original/file-20200505-83740-etd1qe.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=577&fit=crop&dpr=1 754w, https://images.theconversation.com/files/332882/original/file-20200505-83740-etd1qe.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=577&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/332882/original/file-20200505-83740-etd1qe.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=577&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A territory map for anoles shows how these lizards each have their own home turf that can overlap with neighbors. Habitat in this case included individual trees and a fallen log toward the bottom of the map which offered basking and display space.</span>
<span class="attribution"><a class="source" href="https://scholar.google.com/citations?user=WmrOSi4AAAAJ&hl=en">Jordan Bush</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>I like to think of animal territories as quilts that drape over your neighborhood. For some species, like anoles, the squares in that quilt will have many small and intricate pieces, and you could fit many quilt pieces within each individual human property boundary. Some of those pieces will even overlap other patches.</p>
<p>Small songbirds will have quilt patches that span several human properties, though they may use specific parts more than others. Larger species will have quilt patches that cover entire neighborhoods with one territory.</p>
<h2>Frequently spotted</h2>
<p>If you’ve become familiar with the animals in your neighborhood, chances are you’ll see some of the same individuals again year after year. Eastern cottontails are likely to live <a href="http://www.biokids.umich.edu/critters/Sylvilagus_floridanus/">up to three years in the wild</a>, and they <a href="https://doi.org/10.2307/1374932">stay in the same general territory</a> throughout their lives. Even the young have a tendency to stay close to their birth place.</p>
<p>Researchers have recaptured gray squirrels year after year in their original territories. On average, these critters survive about <a href="https://www.esf.edu/aec/adks/mammals/gray_squirrel.htm">six years and can live longer than 20</a>.</p>
<p><div data-react-class="InstagramEmbed" data-react-props="{"url":"https://www.instagram.com/p/B_tBzpJA5FI","accessToken":"127105130696839|b4b75090c9688d81dfd245afe6052f20"}"></div></p>
<p>Birds also have long lives and <a href="https://doi.org/10.1111/j.1600-048X.2011.05520.x">will often stay in the</a> <a href="https://doi.org/10.5253/078.096.0211">same territory year after year</a>. However, when eggs don’t hatch or young die in the nest, some birds may choose a new territory the following year. This means there can be high turnover in your local bird network if the local habitat is <a href="https://doi.org/10.1650/CONDOR-16-72.1">unpredictable or full of urban predators</a>.</p>
<p>Birds that don’t migrate and <a href="https://www.jstor.org/stable/4163451">stay in residence year-round</a>, like chickadees, often have a tendency to <a href="https://doi.org/10.2307/1939172">stay in the same area</a>, which means you’ll be seeing the same individual birds outside your window across seasons.</p>
<p>Some species will have territories that don’t overlap much at all. For others, the <a href="https://doi.org/10.2307/1381990">overlap can be extensive</a>.</p>
<p>This means that generally during the breeding season, you could be watching many gray squirrels visiting outside your window.</p>
<p>There may also be a couple of male cottontails, but probably a single female because they tend to not overlap with other females.</p>
<p>Maybe you’ll spy the same pair of cardinals along with a reliable pair of chickadees. If you’re watching closely like I was the other day, you may get lucky and catch another male cardinal from the territory next door trying to flirt with your female, at least until her mate realizes what’s about to happen. That is a clue to the invisible lines birds have drawn between their own domains.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/333490/original/file-20200507-49573-yhrt4k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/333490/original/file-20200507-49573-yhrt4k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/333490/original/file-20200507-49573-yhrt4k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/333490/original/file-20200507-49573-yhrt4k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/333490/original/file-20200507-49573-yhrt4k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/333490/original/file-20200507-49573-yhrt4k.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/333490/original/file-20200507-49573-yhrt4k.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/333490/original/file-20200507-49573-yhrt4k.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Plenty of anole territories can fit into one human-scaled backyard.</span>
<span class="attribution"><a class="source" href="https://www.instagram.com/p/BqJGf3TBM4c/">Julian Avery</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>When it comes to smaller animals, like lizards and insects, all bets are off for how many unique individuals are present outside your window. But you can expect more of everything as the number of <a href="https://doi.org/10.1016/j.biocon.2017.06.029">native plants</a> <a href="https://doi.org/10.1073/pnas.1809259115">increases</a>.</p>
<h2>Tips for watching</h2>
<p>If you’re interested in trying to keep track of particular wildlife friends through the window, try to watch for identifying marks.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/333486/original/file-20200507-49573-1im5u53.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/333486/original/file-20200507-49573-1im5u53.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/333486/original/file-20200507-49573-1im5u53.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=568&fit=crop&dpr=1 600w, https://images.theconversation.com/files/333486/original/file-20200507-49573-1im5u53.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=568&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/333486/original/file-20200507-49573-1im5u53.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=568&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/333486/original/file-20200507-49573-1im5u53.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=713&fit=crop&dpr=1 754w, https://images.theconversation.com/files/333486/original/file-20200507-49573-1im5u53.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=713&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/333486/original/file-20200507-49573-1im5u53.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=713&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Natural markings like a torn ear can help you keep track of individuals.</span>
<span class="attribution"><a class="source" href="https://www.instagram.com/p/B_p-gZ0g0UG/">Julian Avery</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p><a href="https://doi.org/10.1007/s10531-018-01693-5">In my research, I attach</a> <a href="https://doi.org/10.1111/mec.12236">colored bands to bird legs</a> or mark the scales of turtles and snakes so we can figure out how many exist in an area. Many animals have enough individual variation that you can keep track of them using their natural unique marks and scars. Squirrels can have torn ears or injured tails, lizards can have unique scars or healed injuries, and birds can have subtle differences in color or pattern.</p>
<p>Also try paying attention to the maximum number you see at any one point. Where do they go after eating or basking? You may get lucky and spy a nest or resting place. See if you can spot other individuals coming from different directions and territories.</p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/333487/original/file-20200507-49579-119tf0y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/333487/original/file-20200507-49579-119tf0y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/333487/original/file-20200507-49579-119tf0y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=549&fit=crop&dpr=1 600w, https://images.theconversation.com/files/333487/original/file-20200507-49579-119tf0y.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=549&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/333487/original/file-20200507-49579-119tf0y.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=549&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/333487/original/file-20200507-49579-119tf0y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=690&fit=crop&dpr=1 754w, https://images.theconversation.com/files/333487/original/file-20200507-49579-119tf0y.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=690&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/333487/original/file-20200507-49579-119tf0y.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=690&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Maybe you’ll notice animal families expanding.</span>
<span class="attribution"><span class="source">Julian Avery</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>At my house, we had a nest of rabbit kits born under our deck. I thought there was only one surviving newborn because we never saw more than one offspring. Two weeks later, there were three babies foraging simultaneously in the yard, and it became clear that they’d previously been taking turns coming out of hiding.</p>
<p>If you start watching closely, I think you’ll find so much drama happening in your neighborhood that you may get hooked on the action.</p>
<p>[<em>Get facts about coronavirus and the latest research.</em> <a href="https://theconversation.com/us/newsletters?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=upper-coronavirus-facts">Sign up for The Conversation’s newsletter.</a>]</p><img src="https://counter.theconversation.com/content/136095/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Julian Avery does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>With careful observation, you can start to recognize that one sassy squirrel or the cardinal pair who call your neighborhood home.Julian Avery, Assistant Research Professor of Wildlife Ecology and Conservation, Penn StateLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1336302020-04-02T23:45:32Z2020-04-02T23:45:32ZThis lizard lays eggs and gives live birth. We think it’s undergoing a major evolutionary transition<figure><img src="https://images.theconversation.com/files/320542/original/file-20200315-50538-1hweilq.jpg?ixlib=rb-1.1.0&rect=33%2C16%2C3657%2C2058&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Nicholas Wu</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Our earliest vertebrate (animals with backbones) ancestors laid eggs, but over millions of years of evolution, some species began to give birth to live young. </p>
<p>There is a traditional dichotomy in vertebrate reproduction: species either lay eggs or have live births. However, as is often the case in biology, things aren’t as simple as they first appear, and there are a handful of vertebrate animals that do both.</p>
<p>One of these is the three-toed skink (<em>Saiphos equalis</em>). <a href="https://onlinelibrary.wiley.com/doi/10.1111/mec.15409">Our recent research</a> suggests the egg-laying <em>S. equalis</em> may currently be in the process of transitioning from egg-laying to giving live birth.</p>
<p>Studying them gives us a unique opportunity to watch evolution in action.</p>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/320547/original/file-20200315-50543-2fa3gj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/320547/original/file-20200315-50543-2fa3gj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/320547/original/file-20200315-50543-2fa3gj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/320547/original/file-20200315-50543-2fa3gj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/320547/original/file-20200315-50543-2fa3gj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/320547/original/file-20200315-50543-2fa3gj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/320547/original/file-20200315-50543-2fa3gj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"><em>Saiphos equalis</em> has a distinctive yellow belly, and a long, slender body, ideal for its underground lifestyle.</span>
<span class="attribution"><span class="source">Charles Foster</span></span>
</figcaption>
</figure>
<h2>From eggs to babies, and back again?</h2>
<p>There are two main reproductive strategies in vertebrates. </p>
<p>Animals that lay eggs are called “oviparous”. For instance, many fish species spawn eggs that are fertilised externally. In other oviparous species, including birds and some lizards and snakes, eggs are fertilised inside the mother, an eggshell is added, and then eggs are laid. </p>
<p>Depending on the species, much or all of the nutrition needed to grow a healthy baby is supplied in the egg yolk.</p>
<p>In contrast, “viviparous” animals carry embryos internally until they are fully developed. The embryos can rely entirely on yolk for nutrition, or the parents can provide supplementary nutrition, sometimes via a placenta (as in humans).</p>
<p>There is strong evidence that <a href="https://www.ncbi.nlm.nih.gov/pubmed/24652663">egg-laying is ancestral to live birth</a>, meaning it came first. Many physiological changes were necessary for live birth to have evolved from egg-laying. With this transition, some structures were lost, including the hard outer eggshell. Other mechanisms were gained to ensure embryonic survival within the parent, including the supply of adequate oxygen and water during development.</p>
<p>The evolution of live birth has occurred frequently, <a href="https://www.ncbi.nlm.nih.gov/pubmed/24652663">including at least 121 times in independent groups of reptiles</a>. </p>
<p>Evolutionary “reversals” to egg-laying are much rarer, probably because <a href="https://onlinelibrary.wiley.com/doi/abs/10.1002/jez.b.22614">regaining the physiological machinery for producing eggshells</a> would be exceptionally difficult.</p>
<h2>¿Por que no los dos?</h2>
<p>Despite the vast differences between egg-laying and live birth, some species can do both. This phenomenon called “bimodal reproduction” is exceptionally rare. There are <a href="http://reptile-database.reptarium.cz/search?search=lizard&submit=Search">more than 6500 species of lizards worldwide</a>, but only three exhibit bimodal reproduction. </p>
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Read more:
<a href="https://theconversation.com/lizards-help-us-find-out-which-came-first-the-baby-or-the-egg-29954">Lizards help us find out which came first: the baby or the egg?</a>
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<p>We’re lucky enough to have two of these in Australia. <a href="https://www.camillawhittington.com/">Our research group</a> at the University of Sydney studies the bimodally reproductive three-toed skink, in the hope of understanding how live birth evolved. </p>
<p>In northern NSW, the three-toed skink <a href="https://www.publish.csiro.au/zo/zo97023">gives birth to live young, but near Sydney, they lay eggs</a>. Even though they reproduce differently, <a href="https://academic.oup.com/biolinnean/article/74/2/131/2639614">previous research</a> has shown these lizards are a single species.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/320548/original/file-20200315-50551-w9rfd1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/320548/original/file-20200315-50551-w9rfd1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=637&fit=crop&dpr=1 600w, https://images.theconversation.com/files/320548/original/file-20200315-50551-w9rfd1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=637&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/320548/original/file-20200315-50551-w9rfd1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=637&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/320548/original/file-20200315-50551-w9rfd1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=801&fit=crop&dpr=1 754w, https://images.theconversation.com/files/320548/original/file-20200315-50551-w9rfd1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=801&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/320548/original/file-20200315-50551-w9rfd1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=801&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The three-toed skink displays geographic variation in reproductive mode. It has four very tiny legs, and only three toes per foot.</span>
<span class="attribution"><span class="source">Yi-Kai Tea</span></span>
</figcaption>
</figure>
<p>Even the egg-laying members of the species are odd, as the eggs are retained within the mother for a relatively long time. After being laid, ordinary skink eggs are <a href="https://onlinelibrary.wiley.com/doi/abs/10.1046/j.1420-9101.1998.11010063.x">incubated for at least 35 days</a> before they hatch, but some three-toed skink eggs <a href="https://www.publish.csiro.au/zo/zo97023">hatch in as few as five days</a> after being laid.</p>
<p>One female even <a href="https://theconversation.com/the-first-known-case-of-eggs-plus-live-birth-from-one-pregnancy-in-a-tiny-lizard-113460">laid eggs and gave birth to a live baby in the same litter</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/320543/original/file-20200315-50583-1psbn01.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/320543/original/file-20200315-50583-1psbn01.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/320543/original/file-20200315-50583-1psbn01.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=418&fit=crop&dpr=1 600w, https://images.theconversation.com/files/320543/original/file-20200315-50583-1psbn01.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=418&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/320543/original/file-20200315-50583-1psbn01.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=418&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/320543/original/file-20200315-50583-1psbn01.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=525&fit=crop&dpr=1 754w, https://images.theconversation.com/files/320543/original/file-20200315-50583-1psbn01.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=525&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/320543/original/file-20200315-50583-1psbn01.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=525&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">An egg-laying three-toed skink from near Sydney with its clutch of eggs.</span>
<span class="attribution"><span class="source">Stephanie Liang</span></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-first-known-case-of-eggs-plus-live-birth-from-one-pregnancy-in-a-tiny-lizard-113460">The first known case of eggs plus live birth from one pregnancy in a tiny lizard</a>
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<h2>The genetics behind different reproductive modes</h2>
<p>Most aspects of an animal’s development are controlled by its genes, but not every gene is always active. Genes can be expressed (switched on) to different degrees, and gene expression can stop when not needed.</p>
<p>An egg-laying skink uterus undergoes <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5174741/">only a couple of genetic changes</a> between being empty and holding an egg. </p>
<p>A live-bearing skink uterus is different. It undergoes <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3318437/">thousands of genetic changes</a> to help support the developing baby, including genes that probably help provide oxygen and water, and regulate the mother’s immune system to keep the baby safe from <a href="https://www.sciencemag.org/news/2018/01/key-successful-pregnancy-tamed-immune-reaction">immunological attack</a>.</p>
<h2>Unexpected similarities between the egg-laying and the live-bearing</h2>
<p><a href="https://onlinelibrary.wiley.com/doi/10.1111/mec.15409">Our research</a> measured changes in gene expression between egg-laying and live-birth in the three-toed skink. We investigated how the expression of all genes in the uterus differed between when the uterus was empty and when it held an egg or embryo.</p>
<p>As expected, live-bearing <em>S. equalis</em>, undergo thousands of genetic changes during pregnancy to produce a healthy baby. </p>
<p>But surprisingly, when we looked at the uterus of the egg-laying <em>S. equalis</em>, we found these also undergo thousands of genetic changes, many of which are similar to those in their live-bearing counterparts. </p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/320544/original/file-20200315-50583-15ws3px.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/320544/original/file-20200315-50583-15ws3px.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=444&fit=crop&dpr=1 600w, https://images.theconversation.com/files/320544/original/file-20200315-50583-15ws3px.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=444&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/320544/original/file-20200315-50583-15ws3px.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=444&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/320544/original/file-20200315-50583-15ws3px.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=558&fit=crop&dpr=1 754w, https://images.theconversation.com/files/320544/original/file-20200315-50583-15ws3px.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=558&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/320544/original/file-20200315-50583-15ws3px.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=558&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Embryos of egg-laying Saiphos equalis are nearly completely developed at the time of laying.</span>
<span class="attribution"><span class="source">Stephanie Liang</span></span>
</figcaption>
</figure>
<p>Some of the most important genetic changes in gene expression in egg-laying <em>S. equalis</em> allow embryos to develop within the mother for a long time. These genes also seem to allow the uterus to remodel to accommodate a growing embryo, and drive the same kinds of functions required for the embryonic development in live-birthing three-toed skinks.</p>
<h2>Are ‘reversals’ to egg-laying easier than previously thought?</h2>
<p>Our findings are important because they demonstrate that egg-laying three-toed skinks are an evolutionary intermediate between “true” egg-laying and live birth.</p>
<p>We now know that uterine gene expression in egg-laying <em>S. equalis</em> mirrors live-bearing skinks much more closely than true egg-laying skinks. These results may explain why it’s possible for a female three-toed skink to <a href="https://royalsocietypublishing.org/doi/10.1098/rsbl.2018.0827">lay eggs and give birth to a live baby in a single pregnancy</a>.</p>
<p>The similarities in gene expression between egg-laying and live-bearing three-toed skink uteri might also mean “reversals” from live birth back to egg-laying could be be easier than previously thought. However, this may be restricted to species in which live-birth has evolved recently, such as the three-toed skink.</p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/why-were-not-giving-up-the-search-for-mainland-australias-first-extinct-lizard-117831">Why we're not giving up the search for mainland Australia's 'first extinct lizard'</a>
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<img src="https://counter.theconversation.com/content/133630/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Charles Foster receives funding from The University of Sydney. </span></em></p><p class="fine-print"><em><span>Camilla Whittington receives funding from The University of Sydney and the Australian Research Council. </span></em></p>The three-toed skink can give birth to live young and lay eggs in the same pregnancy. What can this little critter teach us about the evolution of live birth?Charles Foster, Postdoctoral Research Associate, University of SydneyCamilla Whittington, Senior lecturer, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1178312019-05-31T03:42:05Z2019-05-31T03:42:05ZWhy we’re not giving up the search for mainland Australia’s ‘first extinct lizard’<figure><img src="https://images.theconversation.com/files/277135/original/file-20190530-69087-upn4gv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A grassland earless dragon at Jerrabomberra, NSW, November 1991. The search is now on for this species' Victorian cousin.</span> <span class="attribution"><span class="source">CSIRO/Wikimedia Commons</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>You may have seen <a href="https://www.theguardian.com/environment/2019/may/24/elusive-and-cryptic-lizard-hunt-on-in-melbourne-for-endangered-grassland-earless-dragon">news</a> in recent days of the suspected demise of the Victorian grassland earless dragon – now thought to be the first lizard species to be driven to extinction by humans in mainland Australia.</p>
<p>That suspicion arose on the basis of a <a href="https://royalsocietypublishing.org/doi/10.1098/rsos.190233">newly published study</a> in Royal Society Open Science by our research team, in which we discovered that the grassland earless dragons of southeastern Australia are not a single species, but four distinct ones: one that lives around Canberra, two in New South Wales, and one restricted to the Melbourne region.</p>
<p>The most recent confident sighting of the Melbourne species was 50 years ago, in 1969 – hence the fears that the Victorian species has already succumbed.</p>
<p>But despite this worrying news, we’re not leaving this lizard for dead just yet. Conservationists are now combing remaining grassland around Melbourne in a search for survivors.</p>
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Read more:
<a href="https://theconversation.com/ecocheck-victorias-flower-strewn-western-plains-could-be-swamped-by-development-57127">EcoCheck: Victoria's flower-strewn western plains could be swamped by development</a>
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<p>Although no lizard species have previously been declared extinct on the Australian mainland, the grassland earless dragons (<em>Tympanocryptis</em>) of southeastern Australia have long been the subject of conservation concern. Even before being split into four separate species, they were already officially <a href="http://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=66727">listed as endangered</a>.</p>
<p>The Victorian grassland earless dragon (<em>Tympanocryptis pinguicolla</em>) is known only to occur in the native grasslands around Melbourne. A review of historical collections at Museums Victoria show that it was found at several locations including Sunbury, Maribyrnong River (then called “Saltwater River”), and as far west as the Geelong area until the late 1960s.</p>
<p>Although there is little information available about the ecology of this species, it was described by Lucas and Frost in 1894 as:</p>
<blockquote>
<p>Inhabiting stony plains and retreating into small holes, like those of the ‘Trap-door Spider,’ in the ground when alarmed […] Often met with under loose basalt boulders.</p>
</blockquote>
<p>The last confirmed sighting was near Geelong in July 1969.</p>
<h2>First mainland extinction?</h2>
<p>Globally, 31 reptiles have been listed as extinct or extinct in the wild, according to the <a href="https://www.iucnredlist.org/">IUCN Red List</a>, the global authority on the status of species. Two <a href="https://theconversation.com/australian-endangered-species-christmas-island-forest-skink-18053">skinks</a> and one gecko species have been declared extinct in the wild on Christmas Island, a remote Australian territory in the Indian Ocean. But until now there have been no recorded reptile extinctions on the Australian mainland.</p>
<p>Yet it is too early to give up on the Australian grassland earless dragon. Zoos Victoria researchers have completed a mapping analysis <a href="https://search.informit.com.au/documentSummary;dn=343920141519318;res=IELHSS;type=pdf">of potential grassland habitats</a>. But this doesn’t give us enough information to say whether or not any grassland earless dragons remain.</p>
<p>There are several factors that leave open the possibility that the Victorian grassland earless dragon is still clinging to survival. There are some remaining habitat areas that have not yet been surveyed, and this species is small, secretive and hard to find. We urgently need more surveys to try and find any remaining populations.</p>
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Read more:
<a href="https://theconversation.com/vale-gump-the-last-known-christmas-island-forest-skink-30252">Vale 'Gump', the last known Christmas Island Forest Skink</a>
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<p>If these lizards are not yet extinct, their protection will clearly become an urgent conservation priority. But it is hard to develop a conservation program without knowing where the target species actually lives, or indeed whether it is still alive at all.</p>
<p>Zoos Victoria is now <a href="https://hes32-ctp.trendmicro.com:443/wis/clicktime/v1/query?url=https%3a%2f%2fwww.zoo.org.au%2ffighting%2dextinction%2fpriority%2dnative%2dthreatened%2dspecies%2fgrassland%2dearless%2ddragon&umid=5c0bb581-6efa-4859-95ef-4d4593cadecd&auth=89a422ce48cf9afc268cabe806cc53ea452e36bd-0c24bea693dd25d3d890600271201bbd176c25fd">leading a campaign</a>, alongside expert ecologists and local communities, to try and confirm the presence or absence of the Victorian grassland earless dragon. This involves various methods, including habitat mapping, camera trapping, and active searching. The team is also working to identify unsurveyed areas that might potentially be home to these elusive lizards. </p>
<p>Last year the team deployed a series of small <a href="https://www.animalethics.org.au/policies-and-guidelines/wildlife-research/pitfall-traps">pitfall traps</a> at two locations in Little River. Unfortunately, no earless dragons were detected during the survey and few lizards of any species were caught, despite the fact that these locations seemed to offer appropriate food and habitat.</p>
<p>The team is not giving up yet and is committed to continuing the search, with Zoos Victoria researchers having identified sites with suitable habitat both within and outside of the historical distribution, which they aim to survey intensively over the coming years. Meanwhile, reptile keepers at Zoos Victoria are developing husbandry techniques to help look after the grassland earless dragon species from Canberra and NSW.</p>
<p>The conservation challenge has got harder, because where previously we were tasked with looking after one species, we now have to safeguard at least three – and hopefully four!</p>
<hr>
<p><em>This article is based on a blog post that originally appeared <a href="https://collections.museumvictoria.com.au/articles/16665">here</a>. It was coauthored by Adam Lee and Deon Gilbert of Zoos Victoria.</em></p><img src="https://counter.theconversation.com/content/117831/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jane Melville received funding for this research from the Department of Environment and Planning, ACT Government. </span></em></p>The Victorian grassland earless dragon may well be the first lizard species driven to extinction on Australia’s mainland. But conservationists aren’t ready to declare it dead just yet.Jane Melville, Senior Curator, Terrestrial Vertebrates, Museums Victoria Research InstituteLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1134602019-04-02T23:14:51Z2019-04-02T23:14:51ZThe first known case of eggs plus live birth from one pregnancy in a tiny lizard<p>For most animals, reproduction is straightforward: some species lay eggs, while others give birth to live babies. </p>
<p>But our <a href="https://royalsocietypublishing.org/doi/10.1098/rsbl.2018.0827">recent research</a> uncovered a fascinating mix between the two modes of reproduction. In an Australian skink, we observed the first example of both egg-laying and live-bearing within a single litter for any backboned animal. </p>
<p>This suggests some lizards can “hedge their bets” reproductively, taking a punt on both eggs and live-born babies to improve overall survival chances for offspring. </p>
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Read more:
<a href="https://theconversation.com/ancient-fossil-fills-a-75-million-year-gap-and-rewrites-lizard-and-snake-history-97455">Ancient fossil fills a 75 million-year gap and rewrites lizard and snake history</a>
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<h2>Making reproductive leaps</h2>
<p>Most vertebrate species (animals with a backbone) fall neatly into one of two distinctly different reproductive categories. </p>
<p>Oviparous species are egg-layers. These eggs may undergo external fertilisation – such as in spawning fish – or are fertilised and shelled internally, like those of reptiles and birds. Oviparous embryos rely on egg yolk as a source of nutrition to continue development until hatching. </p>
<p>In contrast, viviparous species are live bearers that carry their young to term. Some live-bearing species, including humans, support embryonic development internally via a placenta. <a href="https://www.ncbi.nlm.nih.gov/pubmed/24652663">Egg-laying is ancestral</a>, meaning that modern live-bearers have descended from egg-laying ancestors.</p>
<p>Physiologically, the evolution of live birth from egg-laying is no mean feat. This transition requires a <a href="https://www.ncbi.nlm.nih.gov/pubmed/11923079">whole suite of changes</a>, sometimes including the <a href="https://theconversation.com/using-the-placenta-to-understand-how-complex-organs-evolve-70107">evolution of a placenta</a> – an entirely new specialist organ – as well as loss of the hard outer eggshell, and keeping the embryo inside the body for a longer time. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/266982/original/file-20190402-177181-r7xy8r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/266982/original/file-20190402-177181-r7xy8r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/266982/original/file-20190402-177181-r7xy8r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/266982/original/file-20190402-177181-r7xy8r.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/266982/original/file-20190402-177181-r7xy8r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/266982/original/file-20190402-177181-r7xy8r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/266982/original/file-20190402-177181-r7xy8r.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The placenta is a highly complex organ. One of its jobs is to transfer nutrition to the developing baby.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/cutting-umbilical-cord-between-newborn-baby-1102051619">from www.shutterstock.com</a></span>
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<p>Despite these complex steps, reptiles, particularly snakes and lizards, appear to be unusually predisposed to making the leap to live birth. This capacity has <a href="https://www.ncbi.nlm.nih.gov/pubmed/24652663">evolved in at least 115 groups of reptiles independently</a>. </p>
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Read more:
<a href="https://theconversation.com/a-hidden-toll-australias-cats-kill-almost-650-million-reptiles-a-year-98854">A hidden toll: Australia's cats kill almost 650 million reptiles a year</a>
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<h2>Having it both ways</h2>
<p>It’s easy to see why reptiles, as a group, are <a href="https://www.ncbi.nlm.nih.gov/pubmed/11923079">fascinating models</a> for studying how live birth evolves from egg-laying. </p>
<p>Of particular interest are two Australian skinks that have both live-bearing and egg-laying individuals (known as being <a href="https://theconversation.com/lizards-help-us-find-out-which-came-first-the-baby-or-the-egg-29954">bimodally reproductive</a>). These lizards are incredibly valuable to evolutionary biologists as they offer a snapshot into evolutionary processes in action. </p>
<p>The three-toed skink <em>Saiphos equalis</em> is one such species. Reproduction in <em>S. equalis</em> <a href="https://academic.oup.com/biolinnean/article/74/2/131/2639614">varies geographically</a>: populations around Sydney lay eggs, while those further north give birth to live young. </p>
<p>Whether individuals are live-bearing or egg-laying seems to be genetically determined: when researchers swap their environmental conditions (by moving them from one site to another), the <a href="http://www.publish.csiro.au/zo/ZO97023">females retain their original reproductive strategy</a>.</p>
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Read more:
<a href="https://theconversation.com/lizards-help-us-find-out-which-came-first-the-baby-or-the-egg-29954">Lizards help us find out which came first: the baby or the egg?</a>
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<h2>Mothers know best</h2>
<p><a href="https://royalsocietypublishing.org/doi/10.1098/rsbl.2018.0827">Our latest research</a> shows this lizard is intriguing in another completely unexpected way. </p>
<p>We observed a live-bearing female that laid three eggs, and then gave birth to a living baby from the same litter weeks later. We incubated two of the eggs, one of which hatched to produce a healthy baby. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/264496/original/file-20190318-28512-b7g67t.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/264496/original/file-20190318-28512-b7g67t.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/264496/original/file-20190318-28512-b7g67t.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=283&fit=crop&dpr=1 600w, https://images.theconversation.com/files/264496/original/file-20190318-28512-b7g67t.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=283&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/264496/original/file-20190318-28512-b7g67t.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=283&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/264496/original/file-20190318-28512-b7g67t.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=355&fit=crop&dpr=1 754w, https://images.theconversation.com/files/264496/original/file-20190318-28512-b7g67t.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=355&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/264496/original/file-20190318-28512-b7g67t.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=355&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A live-bearing female <em>S. equalis</em> in our laboratory colony laid three eggs, one of which hatched to produce a healthy baby.</span>
<span class="attribution"><span class="source">Camilla Whittington</span></span>
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<p>This finding is remarkable for two reasons. First, as far as we are aware, this is the first example of both egg-laying and live birth within a single litter for any vertebrate. </p>
<p>Second, in some cases, individuals may be capable of “switching” between reproductive modes. In other words, as laying eggs and giving birth each come with their own advantages and disadvantages, individuals may be able to “choose” which option best suits the current situation.</p>
<h2>Closer look at eggshells</h2>
<p>To better understand this reproductive phenomenon, we investigated the structure of the egg coverings of these unusual embryos in minute detail (using an advanced technology called scanning electron microscopy). </p>
<p>We found that in this litter, the egg-coverings were thinner than those of normal egg-laying skinks and had structural characteristics that overlapped with those of both egg-layers and live-bearers (which have thinner coverings that are greatly reduced). </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/264499/original/file-20190318-28475-9pey9.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/264499/original/file-20190318-28475-9pey9.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/264499/original/file-20190318-28475-9pey9.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=185&fit=crop&dpr=1 600w, https://images.theconversation.com/files/264499/original/file-20190318-28475-9pey9.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=185&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/264499/original/file-20190318-28475-9pey9.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=185&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/264499/original/file-20190318-28475-9pey9.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=233&fit=crop&dpr=1 754w, https://images.theconversation.com/files/264499/original/file-20190318-28475-9pey9.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=233&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/264499/original/file-20190318-28475-9pey9.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=233&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Egg coverings of <em>S. equalis</em> consist of an outer crust (C) and an inner shell membrane (SM). We compared the structure and thicknesses of these layers of both egg-laying (A) and live-bearing (B) <em>S. equalis</em> to identify similarities with our ‘unusual’ embryos (C).</span>
<span class="attribution"><span class="source">Melanie Laird</span></span>
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<h2>How evolution works</h2>
<p>We still don’t know the trigger that caused this female to lay eggs and give birth to a live baby from the same pregnancy. </p>
<p>However, our findings suggest that species “in transition” between egg-laying and live bearing may hedge their bets reproductively before a true transition to live birth evolves. </p>
<p>Being able to switch between reproductive modes may be advantageous, particularly in changing or uncertain environments. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/266985/original/file-20190402-177199-sq0hc5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/266985/original/file-20190402-177199-sq0hc5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/266985/original/file-20190402-177199-sq0hc5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/266985/original/file-20190402-177199-sq0hc5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/266985/original/file-20190402-177199-sq0hc5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/266985/original/file-20190402-177199-sq0hc5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/266985/original/file-20190402-177199-sq0hc5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The three-toed skink lives in eastern Australia.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/dougbeckers/7464211152/in/photolist-cnA2VJ">Doug Beckers / flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
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<p>For example, extreme cold, drought or the presence of predators can be risky for vulnerable eggs exposed to the environment, meaning that mothers that can carry offspring to term may have the upper hand. </p>
<p>In contrast, lengthy pregnancies can be taxing on the mother, so depositing offspring earlier as an egg may be beneficial in some situations. </p>
<p>We suggest that other species in which live birth has evolved from egg-laying relatively recently may also use flexible reproductive tactics. </p>
<p>Further research into this small Australian lizard, which seems to occupy the grey area between live birth and egg-laying, will help us determine how and why species make major reproductive leaps.</p>
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<strong>
Read more:
<a href="https://theconversation.com/curious-kids-why-do-hens-still-lay-eggs-when-they-dont-have-a-mate-104077">Curious Kids: why do hens still lay eggs when they don't have a mate?</a>
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<img src="https://counter.theconversation.com/content/113460/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Melanie Laird receives funding from The University of Otago. </span></em></p><p class="fine-print"><em><span>Camilla Whittington receives funding from the Australian Research Council. </span></em></p>The evolution of live birth from egg-laying is no mean feat. Now new research reports on the first known example where both eggs and a live birth come from the same lizard pregnancy.Melanie Laird, Postdoctoral Fellow, University of OtagoCamilla Whittington, Senior lecturer, University of SydneyLicensed as Creative Commons – attribution, no derivatives.