tag:theconversation.com,2011:/us/topics/entomology-2465/articlesEntomology – The Conversation2024-03-19T12:23:24Ztag:theconversation.com,2011:article/2237062024-03-19T12:23:24Z2024-03-19T12:23:24ZFemale mosquitoes rely on one another to choose the best breeding sites − and with the arrival of spring, they’re already on the hunt<figure><img src="https://images.theconversation.com/files/582309/original/file-20240315-26-7bf0sq.jpg?ixlib=rb-1.1.0&rect=30%2C0%2C6789%2C4468&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">_Aedes aegypti_, found across much of the U.S., spread Zika, dengue, chikungunya and other viruses.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/aedes-aegypti-mosquito-pernilongo-with-white-spots-royalty-free-image/1282216815">Mailson Pignata/iStock via Getty Images</a></span></figcaption></figure><p><em>Aedes aegypti</em> mosquitoes, one of the <a href="https://www.cdc.gov/mosquitoes/mosquito-control/professionals/range.html">most common species in the U.S.</a>, love everything about humans. They love our <a href="http://dx.doi.org/10.1126/science.adi8213">body heat and odors</a>, which enable them to find us. They love to feed on our blood to make their eggs mature. They even love all the standing water that we create. Uncovered containers, old tires and junk piles collect water and are perfect for breeding. </p>
<p>And with the advent of warm weather across the southern U.S., <a href="https://www.mosquitomagnet.com/articles/mosquito-season">mosquito breeding season is already underway</a>.</p>
<p>Given all the options that <em>Aedes</em> females have in urban areas, how do these cosmopolitan mosquitoes find the perfect site to lay their eggs? Scientists previously thought this was a solitary act, but now research shows that female <em>Aedes aegypti</em> mosquitoes – the main vector in the U.S. for diseases such as <a href="https://theconversation.com/explainer-where-did-zika-virus-come-from-and-why-is-it-a-problem-in-brazil-53425">Zika, dengue, chikungunya</a> and other viruses – can rely on one another for good reviews of breeding sites. </p>
<p>Our <a href="https://www.degennarolab.org/">Laboratory of Tropical Genetics</a> at Florida International University discovered a new behavior in which these mosquitoes <a href="https://doi.org/10.1038/s42003-024-05830-5">work together to find suitable egg-laying sites</a>. These findings, recently published in Communications Biology, show that mosquitoes regulate their own population density at breeding sites – an insight that could inform future mosquito control efforts.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/581972/original/file-20240314-30-jxgzpm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A half-dozen mosquitoes spread along the inside of a container." src="https://images.theconversation.com/files/581972/original/file-20240314-30-jxgzpm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/581972/original/file-20240314-30-jxgzpm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=750&fit=crop&dpr=1 600w, https://images.theconversation.com/files/581972/original/file-20240314-30-jxgzpm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=750&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/581972/original/file-20240314-30-jxgzpm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=750&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/581972/original/file-20240314-30-jxgzpm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=943&fit=crop&dpr=1 754w, https://images.theconversation.com/files/581972/original/file-20240314-30-jxgzpm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=943&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/581972/original/file-20240314-30-jxgzpm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=943&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"><em>Aedes aegypti</em> female mosquitoes laying their eggs in a laboratory breeding container.</span>
<span class="attribution"><span class="source">Kaylee Marrero</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
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<h2>Where and why female mosquitoes cluster</h2>
<p>Scientists know that female mosquitoes can be picky when it comes to where they lay their eggs. <em>Aedes aegypti</em> look for human-made breeding sites with relatively clean water, such as birdbaths, tires or even water-filled trash. But given two equal choices, you might expect them to spread evenly between the two. </p>
<p>On the contrary, when we released females in a two-choice test where both breeding site options were equivalent, we repeatedly found more mosquitoes in one chamber than in the other. Furthermore, this occurred irrespective of where the preferred chamber was positioned, whether the mosquitoes could touch water or whether mosquito eggs were already present at the breeding sites. </p>
<p>Female mosquitoes clearly were following one another in small groups to one breeding site rather than another – a newly discovered behavior in <em>Aedes aegypti</em> that we call aggregation. </p>
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<a href="https://images.theconversation.com/files/581971/original/file-20240314-26-70qvqk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Two ramekins, one with a few black spots in it, the other with many spots." src="https://images.theconversation.com/files/581971/original/file-20240314-26-70qvqk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/581971/original/file-20240314-26-70qvqk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=319&fit=crop&dpr=1 600w, https://images.theconversation.com/files/581971/original/file-20240314-26-70qvqk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=319&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/581971/original/file-20240314-26-70qvqk.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=319&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/581971/original/file-20240314-26-70qvqk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=401&fit=crop&dpr=1 754w, https://images.theconversation.com/files/581971/original/file-20240314-26-70qvqk.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=401&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/581971/original/file-20240314-26-70qvqk.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>
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<span class="caption">The black spots in the container on the right indicate that <em>Aedes aegypti</em> females have chosen it as a place to lay their eggs over the identical site on the left.</span>
<span class="attribution"><span class="source">Kaylee Marrero</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
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<p>The insects evidently preferred not to lay their eggs alone. When we tested 30 mosquitoes in our trials, they chose one site over another by a 2-to-1 margin. However, this changed as the test population increased beyond 30 mosquitoes. When we tested 60 or 90 females, the aggregation disappeared.</p>
<p>This tells us that females can regulate their own density at breeding sites – a response that likely is a mechanism to limit larval competition.</p>
<h2>Mosquitoes are smelling each other</h2>
<p>Mosquitoes largely sense the world through smell, using three families of <a href="https://www.britannica.com/science/olfactory-receptor">olfactory receptors</a>. These receptors detect odors when females are choosing where to lay eggs. But how do females sense each other to regulate their densities at breeding sites? </p>
<p>We explored this question by first placing 15 mosquitoes at one of our two test breeding sites. Other females seeking a place to lay preferred the unoccupied site over the one that was already occupied, even though we had already observed that the mosquitoes preferred not to lay their eggs alone. Something was directing them away from the occupied breeding site; we speculated that it might be carbon dioxide, which is an important cue for mosquitoes in all stages of their life cycle. </p>
<p>When female mosquitoes are looking for a blood meal, they fly toward the odor of CO₂, which all vertebrate animals <a href="https://theconversation.com/why-are-some-people-mosquito-magnets-and-others-unbothered-a-medical-entomologist-points-to-metabolism-body-odor-and-mindset-187957">exhale and release through their skin</a>. After feeding, they fly away from it, likely to avoid the risk of being killed by the host. </p>
<p>Mosquitoes also emit CO₂, and normally other mosquitoes can smell it, thanks to a receptor component called Gr3 in their olfactory organs. But when we released mutant females that lacked a functional Gr3 receptor to seek a place to lay eggs in our two-site test, we found that these insects, which could not detect CO₂, were willing to lay their eggs at preoccupied breeding sites. This suggested that normal mosquitoes might be avoiding the preoccupied laying site because they smelled CO₂ emitted by mosquitoes that were already there.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/EUrOcquy8IU?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Female mosquitoes lay eggs on or near still bodies of water.</span></figcaption>
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<p>To confirm this, we offered two unoccupied breeding sites to females seeking a place to lay. However, we increased CO₂ levels around one of the sites to between 600 and 750 parts per million, compared with the normal level of about 450 to 500 ppm at the other site. We found that <em>Aedes aegypti</em> females avoided the unoccupied sites with elevated CO₂. This behavior appears designed to keep occupied breeding sites from becoming too crowded. </p>
<p>Overall, we found that two families of receptors play a role in the interactions between <em>Aedes aegypti</em> females when they seek breeding sites. Odorant receptors detect an unknown odor, which draws females toward a site; gustatory receptors detect CO₂, which deters females from breeding sites when the carbon dioxide level is high. The balance between these attractive and repellent odors will ultimately determine whether a female chooses or avoids a particular site. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/582583/original/file-20240318-20-i9yyck.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Graphic showing common mosquito breeding sites around home, including gutters and pet dishes." src="https://images.theconversation.com/files/582583/original/file-20240318-20-i9yyck.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/582583/original/file-20240318-20-i9yyck.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/582583/original/file-20240318-20-i9yyck.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/582583/original/file-20240318-20-i9yyck.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/582583/original/file-20240318-20-i9yyck.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/582583/original/file-20240318-20-i9yyck.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/582583/original/file-20240318-20-i9yyck.jpeg?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"></a>
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<span class="caption">Mosquitoes breed in many wet spots, large and small.</span>
<span class="attribution"><a class="source" href="https://www.cabq.gov/environmentalhealth/urban-biology/mosquitoes">City of Albuquerque</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
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<h2>Implications for mosquito control</h2>
<p>Suppressing mosquito populations in urban areas using <a href="https://www.cdc.gov/mosquitoes/mosquito-control/community/larvicides.html">biolarvicides</a> – pesticides made from live bacteria that are toxic to mosquito larvae – is a primary control strategy to limit the spread of deadly diseases such as West Nile virus and Zika virus. This is especially true for <em>Aedes aegypti</em>, which is the most common urban mosquito species that reproduces in artificial breeding sites that humans create. Other control tactics, such as <a href="https://undark.org/2019/10/25/when-residents-say-no-to-aerial-mosquito-spraying/">spraying pesticides over large areas</a>, target beneficial insects as well as mosquitoes and can be controversial. </p>
<p>Knowing that female <em>Aedes aegypti</em> use social cues to pick the best breeding grounds for their young and will move on from a breeding site when it becomes too crowded could lead to new control measures. Interrupting the female mosquito reproductive cycle would reduce the spread of mosquitoes and the spread of diseases that these insects carry.</p><img src="https://counter.theconversation.com/content/223706/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kaylee Marrero receives funding from the National Institutes of Health.</span></em></p><p class="fine-print"><em><span>Andre Luis Costa-da-Silva receives funding from the Centers for Disease Control and Prevention, the Southeastern Center of Excellence in Vector-borne Disease and the National Institutes of Health. Views expressed in this article are his own. </span></em></p><p class="fine-print"><em><span>Matthew DeGennaro receives funding from the Centers for Disease Control and Prevention (CDC), the Southeastern Center of Excellence in Vector-borne Disease and the National Institutes of Health. Views expressed in this article are his own.</span></em></p>Female mosquitoes don’t want to lay their eggs alone, but they don’t want sites that are too crowded either. Understanding what guides their choice could inform new control strategies.Kaylee Marrero, Ph.D. Student and Transdisiplinary Biomolecular and Biomedical Sciences Fellow, Florida International UniversityAndre Luis da Costa da Silva, Research Assistant Professor of Biological Sciences, Florida International UniversityMatthew DeGennaro, Associate Professor of Biological Sciences, Florida International UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2230832024-02-14T00:50:26Z2024-02-14T00:50:26ZNZ votes the red admiral butterfly ‘bug of the year’ – how to make your garden its home<p>New Zealanders traditionally show their love for a special other on Valentine’s Day, so what better time to reveal which insect they feel the most affection for?</p>
<p>The second annual <a href="https://bugoftheyear.ento.org.nz/">Bug of the Year</a> contest has been won by the red admiral butterfly. It received a total of 2,275 votes from the nearly 17,000 votes cast by New Zealanders at home and abroad.</p>
<p>One of our most spectacular butterflies, the red admiral inherits the crown from last year’s inaugural winner, the native bee, or ngaro huruhuru (<em>Leioproctus fulvescens</em>). </p>
<p>While a butterfly beat the other bugs, the <a href="https://bugoftheyear.ento.org.nz/2024-bug-of-the-year-nominees/mt-arthur-giant-weta/">Mt Arthur giant wētā</a>, the ngāokeoke (velvet worm) and the titiwai (glowworm) were close behind, with thousands of votes each.</p>
<p>The <a href="https://ento.org.nz/">Entomological Society of New Zealand</a> began the competition to shed light on the underrepresented and stunningly unique bugs of Aotearoa New Zealand. As interest grows, it is hoped more people will be inspired to create and maintain habitats for these often-endangered species.</p>
<p>Aotearoa is home to over 20,000 different species of bugs – more correctly known as terrestrial invertebrates. They range from vibrant butterflies and iconic wētā to secretive velvet worms and carnivorous land snails. And those are just the species described so far.</p>
<p>There are ten times as many bug species in New Zealand than there are native plants, and over a hundred times more than native bird species. Yet most people don’t know much about them.</p>
<h2>Moths and butterflies aren’t so different</h2>
<p>The red admiral is easily recognisable by its vibrant red and black wings. Its Māori name, kahukura, translates directly as “red cloak or garment”, but can also refer to the atua (deity) represented by the top bow of a double rainbow.</p>
<p>The closely related kahukōwhai, or yellow admiral, has similar colouring, except the underside of its upper wings is creamy yellow. Red admirals are endemic – only found in New Zealand – whereas yellow admirals are also native to Australia.</p>
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Read more:
<a href="https://theconversation.com/unveiling-the-enigmatic-world-of-moths-from-ancient-pollinators-to-whistling-wonders-209590">Unveiling the enigmatic world of moths: from ancient pollinators to whistling wonders</a>
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<p>Aotearoa has over 2,000 species of lepidoptera – butterflies and moths – and roughly 90% of these are endemic. You might be surprised to know there are no clear differences between what are commonly called butterflies and those called moths.</p>
<p>Only 17 of our lepidoptera species are popularly referred to as butterflies. But many of the other 98% – so-called moths – are active during the day and can also be beautifully patterned and coloured.</p>
<p>Because they feed from floral nectar sources and transfer pollen in the process, moths and butterflies are important pollinators. They are also staples in the food chain, forming a large portion of native bird diets.</p>
<h2>Gardens as butterfly habitats</h2>
<p>Like many butterflies worldwide, red admirals are less common than they used to be. While <a href="https://tuigarden.co.nz/inspiration-hub/ideas-and-inspiration/bee-aware-and-bee-friendly/">recent gardening advice</a> has begun to include bee-friendly planting, it is also important to think of other invertebrates, like butterflies, when we plan and cultivate our backyards.</p>
<p>In general, a diversity of simple nectar-rich flowers is <a href="https://nodglobal.com/pollinators-biodiversity-and-healthy-ecosystems/">positively related to pollinator health</a>. And resilient and diverse pollinator populations benefit both natural and created ecosystems like gardens. In turn, they support <a href="https://www.sciencedirect.com/science/article/pii/S2468265922000166">biodiversity and overall environmental health</a> – which all benefits human welfare.</p>
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Read more:
<a href="https://theconversation.com/how-butterflies-conquered-the-world-a-new-family-tree-traces-their-100-million-year-journey-across-the-globe-205487">How butterflies conquered the world: a new 'family tree' traces their 100-million-year journey across the globe</a>
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<p>The Moths and Butterflies of New Zealand Trust conducts an <a href="https://www.nzbutterflies.org.nz/project/habitat-creation/">online course</a> on how to assess, create and maintain butterfly habitats.</p>
<p>Lepidoptera differ from some other invertebrates in that females prefer to (or exclusively) lay their eggs on specific host plants. If preferred host plants are not available, caterpillar survival can be low. </p>
<p>So, while having a variety of flowering plants for adults to feed from is important, providing host plants for caterpillars to develop on is crucial.</p>
<p>It is well known that monarch butterfly caterpillars need to feed on milkweed (swan plant). Similarly, <a href="https://www.nzpcn.org.nz/flora/species/muehlenbeckia-astonii/"><em>Muehlenbeckia</em> species</a> such as climbing pohuehue and shrubby tororaro are important host plants for many native butterflies, as well as many native moths. </p>
<p>Lack of suitable hosts may be one reason red admirals are becoming increasingly uncommon. <a href="https://ourarchive.otago.ac.nz/handle/10523/15709">Recent research</a> has shown the females prefer laying eggs on native nettles, and larvae raised on native nettles outperform those raised on introduced nettles.</p>
<p>Experiments show that the tree nettle ongaonga (<em>Urtica ferox</em>) is an ideal host for red admiral caterpillars. But ongaonga is often removed due to its extremely painful stinging hairs.</p>
<h2>Pollinator protection</h2>
<p>Besides planting with butterflies and moths in mind, there are many other actions you can take in the garden to help make it suitable for thriving pollinator populations.</p>
<p>Some of the <a href="https://www.pnas.org/doi/full/10.1073/pnas.2023989118">biggest threats</a> to insect populations in Aotearoa and the world are related to urbanisation, deforestation and agricultural intensification: loss of habitat and food sources, and pesticide use. </p>
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Read more:
<a href="https://theconversation.com/next-time-you-see-a-butterfly-treasure-the-memory-scientists-raise-alarm-on-these-26-species-159798">Next time you see a butterfly, treasure the memory: scientists raise alarm on these 26 species</a>
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<p>Introduced predators also threaten our unique bugs. Invasive <a href="https://www.landcareresearch.co.nz/discover-our-research/biodiversity-biosecurity/invasive-invertebrates/vespula-wasps/wasp-impacts-on-biodiversity/">vespula wasps</a> and rodents are a menace to native butterflies and moths. But <a href="https://predatorfreenz.org/get-involved/backyards-and-neighbourhoods/backyard-trapping/">predator control systems</a> such as backyard trapping can make a difference.</p>
<p>Future articles will offer seasonal advice on gardening and lifestyle practices to help bugs in your backyard. This will include the best times to spot native and introduced bugs, and other ways to promote invertebrate conservation and biodiversity.</p>
<p>Whether you’re already a bug lover or still a bit bug-tentative, it’s important we all help invertebrate populations in Aotearoa survive and thrive.</p>
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<p><em>The authors gratefully acknowledge the help of the <a href="https://www.nzbutterflies.org.nz/">Moths and Butterflies of New Zealand Trust</a> in the preparation of this article.</em> </p>
<hr><img src="https://counter.theconversation.com/content/223083/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Janice Lord is a member of the Entomological Society of New Zealand.</span></em></p><p class="fine-print"><em><span>Connal McLean is a volunteer with The Moths and Butterflies of New Zealand Trust. </span></em></p>The native red admiral is less common than it used to be, but we can all help threatened bug species by ensuring they have the right habitats to thrive in.Janice Lord, Associate Professor in Botany, University of OtagoConnal McLean, Natural History Technician – Invertebrates, Te Papa TongarewaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2213872024-01-30T16:01:27Z2024-01-30T16:01:27ZThe surprising reason why insects circle lights at night: They lose track of the sky<figure><img src="https://images.theconversation.com/files/571170/original/file-20240124-21-ynct7x.png?ixlib=rb-1.1.0&rect=30%2C20%2C6679%2C4446&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A multiple-exposure photograph of insects circling a light at night.</span> <span class="attribution"><span class="source">Samuel Fabian</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>It’s an observation as old as humans gathering around campfires: Light at night can draw an erratically circling crowd of insects. In art, music and literature, this spectacle is an enduring metaphor for <a href="https://roundglasssustain.com/wildvaults/moths">dangerous but irresistible attractions</a>. And watching their frenetic movements really gives the sense that something is wrong – that instead of finding food and evading predators, these nocturnal pilots are trapped by a light.</p>
<p>Sadly, centuries of witnessing what happens have produced little certainty about why it happens. How does a simple light change fast, precise navigators into helpless, flittering captives? We are researchers examining <a href="https://scholar.google.co.uk/citations?user=wG5HGs8AAAAJ&hl=en">flight</a>, <a href="https://scholar.google.com/citations?user=4i4wRGgAAAAJ&hl=en">vision</a> and <a href="https://scholar.google.co.in/citations?user=X-j5RnwAAAAJ&hl=en">evolution</a>, and we have used high-speed tracking techniques in <a href="https://www.nature.com/articles/s41467-024-44785-3">newly published research</a> to provide an answer.</p>
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<figcaption><span class="caption">The reason insects fly around light will surprise you.</span></figcaption>
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<h2>Moths to a flame?</h2>
<p>Many old explanations for this hypnotic behavior have not fully panned out. An early notion was that the insects might be attracted to the heat of a flame. This was interesting, as some insects really <a href="https://doi.org/10.1016/j.foreco.2022.120629">are pyrophilic</a>: They are attracted to fire and have evolved to take advantage of conditions in recently burned areas. But most insects around a light are not in this category, and cool lights attract them quite well. </p>
<p>Another thought was that insects were just directly attracted to light, a <a href="https://doi.org/10.1007/s13355-013-0219-x">response called phototaxis</a>. Many insects move toward light, perhaps as a way to escape dark or entrapping surroundings. But if this were the explanation for the clusters around a light, you might expect them to bump straight into the source. This theory does little to explain the wild circling behavior.</p>
<p>Still another idea was that insects might mistake a nearby light for the Moon, as they attempted to use <a href="https://doi.org/10.1146/annurev.en.29.010184.001425">celestial navigation</a>. Many insects reference the Moon to keep their course at night.</p>
<p>This strategy relies on how objects at great distance seem to hover in place as you move along a straight path. A steady Moon indicates that you have not made any unintentional turns, as you might if you were buffeted by a gust of wind. Nearer objects, however, don’t appear to follow you in the sky but drift behind as you move past.</p>
<p>The celestial navigation theory held that insects worked to keep this light source steady, turning sharply in a failed attempt to fly straight. An elegant idea, but this model predicts that many flights will spiral inward to a collision, which doesn’t usually match the orbits we see. So what’s really going on?</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/571761/original/file-20240128-21-f7q5vs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Several cameras face a bright light on a stand in a forest setting at night." src="https://images.theconversation.com/files/571761/original/file-20240128-21-f7q5vs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/571761/original/file-20240128-21-f7q5vs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/571761/original/file-20240128-21-f7q5vs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/571761/original/file-20240128-21-f7q5vs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/571761/original/file-20240128-21-f7q5vs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/571761/original/file-20240128-21-f7q5vs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/571761/original/file-20240128-21-f7q5vs.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"></a>
<figcaption>
<span class="caption">Scientists used high-speed stereo motion capture to document how the presence of artificial light at night affects insects’ flight behavior.</span>
<span class="attribution"><span class="source">Samuel Fabian</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Turning their backs to the light</h2>
<p>To examine this question in detail, we and our colleagues captured high-speed videos of insects around different light sources to precisely determine flight paths and body postures, both in the lab at <a href="https://www.imperial.ac.uk">Imperial College London</a> and at two field sites in Costa Rica, <a href="https://www.ciee.org/go-abroad/college-study-abroad/locations/costa-rica/monteverde">CIEE</a> and the <a href="https://www.estacionbiologica.com/">Estación Biológica</a>. We found that their flight patterns weren’t a close match for any existing model. </p>
<p>Rather, a broad swath of insects consistently pointed their backs toward the lights. This is a known behavior called the <a href="https://doi.org/10.1146/annurev.en.29.010184.001425">dorsal light response</a>. In nature, assuming that more light comes down from the sky than up from the ground, this response helps keep insects in the proper orientation to fly.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/qECYfEN70qs?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Artificial light at night interrupts the normal flight patterns of insects. This compilation video shows an orbiting behavioral motif in which insects circle the light.</span></figcaption>
</figure>
<p>But pointing their backs toward nearby artificial lights alters their flight paths. Just as airplanes bank to turn, sometimes rolling until the ground seems nearly straight out your window, banking insects turn as well. When their backs orient to a nearby light, the resulting bank loops them around the light, circling but rarely colliding. </p>
<p>These orbiting paths were only one of the behaviors we observed. When insects flew directly under a light, they often arched upward as it passed behind them, keeping their backs to the bulb until, eventually flying straight up, they stalled and fell out of the air. And even more compelling, when flying directly over a light, insects tended to flip upside down, again turning their backs to the light but then abruptly crashing.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/571763/original/file-20240128-21-1bjvpv.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Diagrams show insects rolling vertically or horizontally or inverting in the presence of artificial light." src="https://images.theconversation.com/files/571763/original/file-20240128-21-1bjvpv.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/571763/original/file-20240128-21-1bjvpv.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=410&fit=crop&dpr=1 600w, https://images.theconversation.com/files/571763/original/file-20240128-21-1bjvpv.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=410&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/571763/original/file-20240128-21-1bjvpv.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=410&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/571763/original/file-20240128-21-1bjvpv.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=515&fit=crop&dpr=1 754w, https://images.theconversation.com/files/571763/original/file-20240128-21-1bjvpv.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=515&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/571763/original/file-20240128-21-1bjvpv.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=515&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Three different observed turning behaviors in which flying insects turn their backs to artificial light.</span>
<span class="attribution"><span class="source">Jamie Theobald</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Why have a dorsal light response?</h2>
<p>Although light at night can harm <a href="https://www.jstor.org/stable/43597777">other animals</a> – for example, by <a href="https://doi.org/10.1073/pnas.1708574114">diverting migrating birds into urban areas</a> – larger animals don’t seem to lose their vertical orientation. So why do insects, the oldest and most species-rich group of flyers, rely on a response that leaves them so vulnerable?</p>
<p>It may have to do with their small size. Larger animals can sense gravity directly with sensory organs pulled by its acceleration, or any acceleration. Humans, for example, use the <a href="https://www.ncbi.nlm.nih.gov/books/NBK279394/">vestibular system of our inner ear</a>, which regulates our sense of balance and usually gives us a good sense of which way is down.</p>
<p>But insects have only small sensory structures. And especially as they perform rapid flight maneuvers, acceleration offers only a poor indication of which way is down. Instead, they seem to bet on the brightness of the sky. </p>
<p>Before modern lighting, the sky was usually brighter than the ground, day or night, so it provided a fairly reliable cue for a small active flyer hoping to keep a steady orientation. The artificial lights that sabotage this ability, by cueing insects to fly in circles, are relatively recent. </p>
<h2>The growing problem of nighttime lighting</h2>
<p>As new technology spreads, lights that pervade the night are <a href="https://doi.org/10.3390/rs13163311">proliferating faster then ever</a>. With the introduction of cheap, bright, <a href="https://www.energy.gov/eere/ssl/led-basics">broad-spectrum LEDs</a>, many areas, such as large cities, never see a dark night.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/571762/original/file-20240128-31-eh9yyj.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A view upward through treetops to a starry dark sky, with a bright light at the top of the screen from a light bulb near the ground." src="https://images.theconversation.com/files/571762/original/file-20240128-31-eh9yyj.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/571762/original/file-20240128-31-eh9yyj.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/571762/original/file-20240128-31-eh9yyj.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/571762/original/file-20240128-31-eh9yyj.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/571762/original/file-20240128-31-eh9yyj.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/571762/original/file-20240128-31-eh9yyj.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/571762/original/file-20240128-31-eh9yyj.png?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">This upward view at the authors’ field research site in Monteverde, Costa Rica, shows how artificial light competes with the night sky.</span>
<span class="attribution"><span class="source">Samuel Fabian</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Insects aren’t the only creatures affected. Light pollution disrupts circadian rhythms and physiological processes in other <a href="https://darksky.org/resources/what-is-light-pollution/effects/wildlife-ecosystems/">animals, plants</a> and <a href="https://darksky.org/resources/what-is-light-pollution/effects/human-health/">humans</a>, often with <a href="https://theconversation.com/new-atlas-shows-extent-of-light-pollution-what-does-it-mean-for-our-health-60836">serious health consequences</a></p>
<p>But insects trapped around a light seem to get the worst of it. Unable to secure food, easily spotted by predators and prone to exhaustion, many die before the morning comes.</p>
<p>In principle, light pollution is one of the easiest things to fix, often by just <a href="https://www.youtube.com/watch?v=EfhuU5Ceo_w">flipping a switch</a>. <a href="https://darksky.org/what-we-do/advancing-responsible-outdoor-lighting/">Restricting outdoor lighting</a> to useful, targeted warm light, no brighter than necessary, and for no longer than necessary, can greatly improve the health of nocturnal ecosystems. And the same practices that are good for insects help restore views of the night sky: Over one-third of the world population lives in areas where the <a href="http://dx.doi.org/10.1126/sciadv.1600377">Milky Way is never visible</a>. </p>
<p>Although insects circling around a light are a fascinating spectacle, it is certainly better for the insects and the <a href="https://www.si.edu/spotlight/buginfo/benefits">benefits they provide to humans</a> when we leave the night unlit and let them go about the activities they so masterfully perform under the night sky.</p><img src="https://counter.theconversation.com/content/221387/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Samuel Fabian receives funding from the European Research Council and a National Geographic Explorer Grant.</span></em></p><p class="fine-print"><em><span>Jamie Theobald receives funding from the National Science Foundation and the U.S. Air Force Office of Scientific Research.</span></em></p><p class="fine-print"><em><span>Yash Sondhi receives funding from the Florida International University Graduate School, the Susan Levine Foundation, a National Geographic Explorer Grant, the American Philosophical Society, and the Kimberly-Green Latin-American and Caribbean Center.</span></em></p>A new study shows how artificial light at night scrambles insects’ normal flight patterns, pulling them off course into orbit around the light.Samuel Fabian, Postdoctoral Research Associate in Bioengineering, Imperial College LondonJamie Theobald, Associate Professor of Biological Sciences, Florida International UniversityYash Sondhi, Postdoctoral Research Associate in Entomology, Mcguire Center for Lepidoptera & Biodiversity, Florida Museum of Natural History, University of FloridaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2189082023-12-08T02:55:55Z2023-12-08T02:55:55ZFire ants are on the march. Here’s what happens when they sting<figure><img src="https://images.theconversation.com/files/564401/original/file-20231207-28-zox765.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C998%2C666&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/red-fire-ant-1211635918">Veronika Kunitsyna/Shutterstock</a></span></figcaption></figure><p>Red imported fire ants are a particularly nasty type of ant because they are aggressive, and inflict painful stings that may be life threatening. That’s in addition to being a serious threat to <a href="https://www.business.qld.gov.au/industries/farms-fishing-forestry/agriculture/biosecurity/animals/invasive/restricted/fire-ant">agriculture and biosecurity</a>. </p>
<p><a href="https://www.dpi.nsw.gov.au/biosecurity/insect-pests/fire-ants">In recent weeks</a>, we heard these ants <a href="https://www.outbreak.gov.au/current-outbreaks/red-imported-fire-ant">had spread</a> from Queensland, south into northern New South Wales.</p>
<p>Although their stings are rare in Australia, they can lead to a serious allergic reaction. Here’s what to do if you’ve been stung.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-red-fire-ants-and-yellow-crazy-ants-have-given-themselves-a-green-light-to-invade-australia-208479">Why red fire ants and yellow crazy ants have given themselves a green light to invade Australia</a>
</strong>
</em>
</p>
<hr>
<h2>Which ants are we talking about?</h2>
<p>Red imported fire ants (<em>Solenopsis invicta</em>) are native to South America but have been <a href="https://www.ncbi.nlm.nih.gov/books/NBK470576/">spreading across the world</a> in contaminated soil.</p>
<p><a href="https://www.dpi.nsw.gov.au/biosecurity/insect-pests/fire-ants">The ants</a> are 2-6 millimetres long and are a dark red-brown colour. They live in nests in the ground. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/_XL6QWRHZes?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Here’s what red imported fire ants look like (Biosecurity Queensland).</span></figcaption>
</figure>
<p>When a nest is disturbed, hundreds of ants come out and attack. Their jaws lock onto the skin and they arch their body to <a href="https://www.ncbi.nlm.nih.gov/books/NBK470576/">inject venom</a> through a stinger on their abdomen. Each ant stings an average <a href="https://www.ncbi.nlm.nih.gov/books/NBK470576/">seven to eight times</a>.</p>
<p>These ants sting <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8151706/">millions of people</a> a year in the United States.</p>
<p>Anyone who disturbs their nest is at risk of being stung. Even minor disturbances will cause the ants to surface and attack.</p>
<p>Overseas, people have been stung by ants that have <a href="https://pubmed.ncbi.nlm.nih.gov/37355195/">formed rafts</a> during heavy rainfall and flooding.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/from-deadly-jaws-and-enormous-strength-to-mushroom-farming-ant-man-is-only-tapping-into-a-portion-of-the-real-superpowers-of-ants-200530">From deadly jaws and enormous strength to mushroom farming, Ant-Man is only tapping into a portion of the real superpowers of ants</a>
</strong>
</em>
</p>
<hr>
<h2>What happens when this ant stings you?</h2>
<p>Fortunately, red imported fire ant stings have been uncommon in Australia, and we hope it stays this way.</p>
<p><a href="https://www.ncbi.nlm.nih.gov/books/NBK470576/">Their sting</a> is painful, with a fire-like burning character, and is associated with swelling and redness. Over the following hours or days, sting sites develop blisters or pustules that are itchy and take days to improve. </p>
<p>A person can easily be stung hundreds of times, which can cause a lot of distress.</p>
<h2>What’s the treatment? Do I need to go to hospital?</h2>
<p>Many people with a smaller number of stings can be safely managed at home. <a href="https://www.healthdirect.gov.au/insect-bites-and-stings">Usual treatments</a> <a href="https://www.poisonsinfo.health.qld.gov.au/bites-and-stings/insect-bites-and-stings">include</a>:</p>
<ul>
<li><p>gently washing the area with soap and water</p></li>
<li><p>using cold compresses on red and swollen stings. If you use an ice pack or ice, avoid direct contact with the skin</p></li>
<li><p>taking <a href="https://www.healthdirect.gov.au/antihistamines#:%7E:text=What%20are%20antihistamines%3F-,Antihistamines%20are%20medicines%20that%20you%20can%20take%20to%20treat%20allergies,called%20histamine%20in%20your%20body.">antihistamines</a>, which you can buy from your local pharmacy. </p></li>
</ul>
<p>Do not break the blisters that form at sting sites, and see your local doctor if the stings become more red and painful a few days later, to exclude infection.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/bzzz-slap-how-to-treat-insect-bites-home-remedies-included-148722">Bzzz, slap! How to treat insect bites (home remedies included)</a>
</strong>
</em>
</p>
<hr>
<h2>When to seek medical care</h2>
<p>Uncommonly, red imported fire ant stings can be <a href="https://pubmed.ncbi.nlm.nih.gov/2760357/">life threatening</a>. <a href="https://www.ncbi.nlm.nih.gov/books/NBK470576/">About 2%</a> of people who are stung develop a severe and life-threatening allergic reaction known as anaphylaxis. This has also been <a href="https://pubmed.ncbi.nlm.nih.gov/12064982/">reported</a> in Australia. </p>
<p><a href="https://www.allergy.org.au/patients/insect-allergy-bites-and-stings/allergic-reactions-to-bites-and-stings">Many stinging animals</a> in Australia can cause anaphylaxis, including bees, wasps, and other ants such as <a href="https://www.allergy.org.au/patients/insect-allergy-bites-and-stings/jack-jumper-ant-allergy">jack jumper ants</a>.</p>
<p>People allergic to some wasps may also <a href="https://pubmed.ncbi.nlm.nih.gov/26708389/">be allergic</a> to venom from the red fire ants. </p>
<p>Symptoms of anaphylaxis after being stung by a fire ant are similar to those after being stung by other animals. <a href="https://www.allergy.org.au/patients/about-allergy/anaphylaxis">Symptoms include</a>:</p>
<ul>
<li><p>difficulty talking or breathing</p></li>
<li><p>noisy breathing</p></li>
<li><p>swelling of the face (including lips, eyes or tongue)</p></li>
<li><p>tightness in the throat, with difficulty swallowing</p></li>
<li><p>dizziness</p></li>
<li><p>collapsing. </p></li>
</ul>
<p>There may also be a spreading red rash (hives or welts).</p>
<p>If you have any <a href="https://www.allergy.org.au/patients/about-allergy/anaphylaxis">of these symptoms</a>, seek immediate medical assistance. This may including calling 000. </p>
<p>Rarely, the ant venom can cause other toxic effects, which may be more likely in people who have been stung hundreds of times. So seek medical advice if you have unexplained or unusual symptoms after you’ve been stung.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/ants-bees-and-wasps-the-venomous-australians-with-a-sting-in-their-tails-51024">Ants, bees and wasps: the venomous Australians with a sting in their tails</a>
</strong>
</em>
</p>
<hr>
<h2>Avoid these ants if you can</h2>
<p>Avoid exposing yourself to imported red fire ants. Report nests to authorities. Do not handle the nests yourself as this is more likely to spread the ants. This is also when you’re most likely to be stung.</p>
<hr>
<p><em>If this article raises health concerns for you or for someone you know about insect stings call the <a href="https://www.poisonsinfo.nsw.gov.au">Poisons Information Centre</a> from anywhere in Australia on 131 126. This evidence-based advice is available 24 hours a day. For life-threatening symptoms, call 000.</em></p><img src="https://counter.theconversation.com/content/218908/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Darren Roberts is the Medical Director of the NSW Poisons Information Centre </span></em></p>Most stings can be safely handled at home. But in rare cases, you can get a serious allergic reaction, which needs urgent medical attention.Darren Roberts, Conjoint Associate Professor in clinical pharmacology and toxicology, St Vincent’s Healthcare Clinical Campus, UNSW SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2038312023-09-04T12:16:58Z2023-09-04T12:16:58ZHow do flies find every stinky garbage dumpster? A biologist explains their sensory superpower<figure><img src="https://images.theconversation.com/files/538392/original/file-20230719-17-hhlu4f.jpg?ixlib=rb-1.1.0&rect=70%2C60%2C6619%2C4406&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The blow fly's antenna is a specialized organ that helps the fly detect food quicker than its competitors. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/gold-fly-on-food-royalty-free-image/1170893429?adppopup=true">heckepics/iStock via Getty Images </a></span></figcaption></figure><figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=293&fit=crop&dpr=1 600w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=293&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=293&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=368&fit=crop&dpr=1 754w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=368&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=368&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><em><a href="https://theconversation.com/us/topics/curious-kids-us-74795">Curious Kids</a> is a series for children of all ages. If you have a question you’d like an expert to answer, send it to <a href="mailto:curiouskidsus@theconversation.com">curiouskidsus@theconversation.com</a>.</em></p>
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<blockquote>
<p><strong>How do the green-and-blue flies find stinky garbage dumpsters during the summer heat? Joey, 10, Wausau, Wisconsin</strong></p>
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<hr>
<p>How is it that a fly always seems to be buzzing around your food moments after you sit down for an outdoor meal?</p>
<p>The answer is practice. Or, more specifically: evolution. Flies and other insects have been on a multimillion-year journey of evolution, honing their ability to detect food. Being able to zero in on nutritious meals is a matter of life and death. </p>
<p>The family of flies <a href="https://science.iupui.edu/biology/research/faculty-labs/picard-lab/index.html">that I study</a> – the blow flies – are the buzzing ones that are usually a beautiful metallic blue, with bronze and green colors. They’ve perfected their ability to quickly sense the smells that naturally come off picnics and trash cans because they are a source of food for their offspring, also known as <a href="https://www.britannica.com/science/maggot-insect-larva">maggots</a>. </p>
<p>There is a lot of competition for a resource like an overflowing dumpster because of how nutritious garbage, and the meat that is rotting in it, is. But the blow flies can sense these odors long before their competitors or people can, and tend to <a href="https://www.theguardian.com/science/2010/sep/23/flies-murder-natural-history-museum">show up to the scene first</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/538065/original/file-20230718-27-j1dmtd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Fly eats meat." src="https://images.theconversation.com/files/538065/original/file-20230718-27-j1dmtd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/538065/original/file-20230718-27-j1dmtd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/538065/original/file-20230718-27-j1dmtd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/538065/original/file-20230718-27-j1dmtd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/538065/original/file-20230718-27-j1dmtd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/538065/original/file-20230718-27-j1dmtd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/538065/original/file-20230718-27-j1dmtd.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">Flies’ antennae help them track down food from far distances.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/adult-greenbottle-fly-royalty-free-image/1406254324?phrase=flies%2Beating%2Bmeat">ViniSouza128/iStock via Getty Images</a></span>
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<h2>How do flies know where to go?</h2>
<p>Sensing systems differ depending on the insect and species. The blow flies’ main sensing organ is their <a href="https://en.wikipedia.org/wiki/Antenna_(biology)">antennae</a>, two thin projections from the head that are covered in tiny hairs. These fine hairs are made up of special cells that contain <a href="https://doi.org/10.1007/s00253-011-3417-x">receptors for specific odors</a>. </p>
<p>Think about a batch of chocolate chip cookies fresh from the oven. You can detect their delicious scent because we humans have receptors on the surfaces of the cells that line the inside of our noses. These receptors send signals to the brain: yummy food ahead. They’re detecting the sweet smell of sugar-based molecules, an energy-rich food source for us. </p>
<p>What’s a “good” or a “bad” odor can differ depending on the animal doing the smelling. The enticing rotting meat stench that a fly finds delightful is perceived quite differently by a person passing by a stinking dumpster on a hot day.</p>
<p>But any fly that can detect the useful odor signal, which means “nutritious fly food here,” will have an advantage. Over time, the insects that have the receptors for those scents will have better survival rates and produce more offspring.</p>
<p>Not all smells are good, though, and being able to smell something bad can also protect whoever is sniffing it – whether that’s you or an insect. Think of the skunk spray warning smell. It won’t necessarily harm you, but it lets you know to avoid its source. </p>
<figure class="align-center ">
<img alt="A fly has detected a piece of dessert." src="https://images.theconversation.com/files/533741/original/file-20230623-23-6np9vj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/533741/original/file-20230623-23-6np9vj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=381&fit=crop&dpr=1 600w, https://images.theconversation.com/files/533741/original/file-20230623-23-6np9vj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=381&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/533741/original/file-20230623-23-6np9vj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=381&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/533741/original/file-20230623-23-6np9vj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=479&fit=crop&dpr=1 754w, https://images.theconversation.com/files/533741/original/file-20230623-23-6np9vj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=479&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/533741/original/file-20230623-23-6np9vj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=479&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Flies can sense odors long before humans and their competitors can.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/spoiled-dessert-royalty-free-image/1125293670?phrase=fly+insect+food&adppopup=true">Boris SV/Moment via Getty Images</a></span>
</figcaption>
</figure>
<h2>Providing for offspring</h2>
<p>For more than 15 years, I’ve traveled to different parts of the world, where I expose rotten meat and <a href="https://science.iupui.edu/biology/research/faculty-labs/picard-lab/index.html">wait for flies to appear</a>. My research is related to understanding how an environment influences a fly’s ability to search for and find its food source, its sole purpose of living. For example, flies rely on wind to carry scents across varying environments. </p>
<p>Warmer temperatures promote fly activity because they’re <a href="https://en.wikipedia.org/wiki/Poikilotherm">poikilothermic</a> – meaning cold-blooded – and need heat to warm up their muscles for flight. <a href="https://theconversation.com/flies-evade-your-swatting-thanks-to-sophisticated-vision-and-neural-shortcuts-187051">Flies use visual cues</a> to fly through the air and to avoid obstacles, so they’re more active during the daytime.</p>
<p>Blow flies can <a href="https://doi.org/10.1146/annurev.en.10.010165.000403">travel up to 28 miles for food</a>. Most of the time when I expose a stinky rotten meat bait, a large group of flies <a href="https://www.youtube.com/shorts/FZnHA4U0NJM">will come right away</a>. But other times I’m surprised when no flies come to enjoy the gross buffet I’ve prepared.</p>
<p>When a female fly smells something that might be a good food source for her babies, she lands on it and assesses whether there’s enough to support her 400 or so eggs. A mom fly’s ability to smell out a good nursery for her offspring is the key to the survival of the species and ultimately why this sense is so strong. </p>
<p>Male flies are less interested in these smells as a sign of food. But since they can signal where to find female flies for mating, males will still respond to the scent of a steaming dumpster.</p>
<p>Flies have evolved to be superior garbage-smellers because this superpower helps them survive. The reason they manage to find dumpsters wherever they exist is the same reason they’ll show up to your picnic to check what’s on the menu – they’re sniffing for sustenance that will help them create the next generation of flies. </p>
<hr>
<p><em>Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to <a href="mailto:curiouskidsus@theconversation.com">CuriousKidsUS@theconversation.com</a>. Please tell us your name, age and the city where you live.</em></p>
<p><em>And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.</em></p><img src="https://counter.theconversation.com/content/203831/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Christine Picard receives funding from the National Science Foundation, the National Geographic Society, the National Institute of Justice, and the US Department of Defense. </span></em></p>Flies often beat out competitors for food because of their specialized sensing organs called antennae.Christine Picard, Associate Professor of Biology, Indiana UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2086392023-07-04T15:11:39Z2023-07-04T15:11:39ZBiting flies are attracted to blue traps – we used AI to work out why<p>Flies which feast on blood – such as tsetse and horse flies – inflict painful bites and spread debilitating diseases among people and animals alike. So a lot of work has gone into designing the most efficient traps to control the populations of these flies.</p>
<p>Biting fly traps tend to be blue, because decades of field research has shown that such flies find this colour especially attractive. But it’s never been clear why these flies find blue to be so irresistible – especially since blue objects are not a common sight in the natural environment.</p>
<p>Scientists have speculated that blue surfaces might look like <a href="https://royalsocietypublishing.org/doi/10.1098/rsbl.2003.0121">shaded places</a> to flies since shadows have a blueish tinge. Tsetse flies in particular seek out such shaded spots to rest in, which might explain their attraction to blue traps. </p>
<p>Another possibility is that blue surfaces might <a href="https://resjournals.onlinelibrary.wiley.com/doi/full/10.1046/j.1365-2915.1999.00163.x">lure hungry flies</a> by providing them with the telltale signs they use to distinguish animals against a background of foliage. According to this theory, a fly might mistake a blue trap for an animal it wishes to bite and feed upon. </p>
<figure class="align-left ">
<img alt="A blue canvas, diamond shaped container is suspended from a tree." src="https://images.theconversation.com/files/535007/original/file-20230630-24873-ovj9iw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/535007/original/file-20230630-24873-ovj9iw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/535007/original/file-20230630-24873-ovj9iw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/535007/original/file-20230630-24873-ovj9iw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/535007/original/file-20230630-24873-ovj9iw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/535007/original/file-20230630-24873-ovj9iw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/535007/original/file-20230630-24873-ovj9iw.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">A bright blue trap for tsetse flies is suspended from a tree.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/bright-blue-trap-dangerous-tsetse-fly-724357057">Fabian Plock/Shutterstock</a></span>
</figcaption>
</figure>
<p>But assessing these possibilities is especially tricky because flies perceive colour differently to people. Humans perceive colour using the responses of three kinds of light-detecting photoreceptor in the retina which are broadly sensitive to blue, green and red wavelengths of light.</p>
<p>But most “higher flies” – such as tsetse and horseflies – have five kinds of photoreceptor sensitive to UV, blue and green wavelengths. So, a blue trap won’t look the same to a fly as it does to the human who designed it.</p>
<h2>From flies to AI…</h2>
<p>In <a href="https://royalsocietypublishing.org/doi/10.1098/rspb.2023.0463#d1e1574">our study</a>, we tackled the problem by using artificial intelligence (AI). We used artificial neural networks which are a form of machine learning inspired by the structure of real nervous systems. Artificial neural networks learn by modifying the strengths of connections between a network of artificial neurons.</p>
<p>We fed these networks with the photoreceptor signals that a fly would experience when looking at animals or foliage backgrounds, both in light and in shade. We then trained the networks to distinguish animals from leaves, and shaded from unshaded objects, using only that visual information.</p>
<p>The trained networks would find the most efficient way of processing the visual signals, which we expected to share properties with the mechanisms that have evolved in real flies’ nervous systems. We then investigated whether the artificial neural networks classified blue traps as animals or as shaded surfaces.</p>
<h2>Blueness or brightness?</h2>
<p>After training, our neural networks could easily distinguish animals from leaf backgrounds, and shaded from unshaded stimuli, using the sensory information available to a fly. However, what surprised us was that they solved these problems in completely different ways.</p>
<p>The networks identified shade using brightness and not colour – quite simply, the darker a stimulus appeared, the more likely it was to be classified as shaded. Meanwhile, animals were identified using the relative strength of blue and green photoreceptor signals. Relatively greater blue compared to green signals indicated that a stimulus was probably an animal rather than a leaf, and vice versa.</p>
<p>The implications of this became clear when we fed these networks the visual signals caused by blue traps. The blue traps were never mistaken for shaded surfaces, but they were commonly misclassified as animals.</p>
<figure class="align-center ">
<img alt="A close up of an insect with huge blue/green eyes" src="https://images.theconversation.com/files/535038/original/file-20230630-13700-zuvny9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/535038/original/file-20230630-13700-zuvny9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/535038/original/file-20230630-13700-zuvny9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/535038/original/file-20230630-13700-zuvny9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/535038/original/file-20230630-13700-zuvny9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/535038/original/file-20230630-13700-zuvny9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/535038/original/file-20230630-13700-zuvny9.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 horse fly (<em>Hybomitra epistates</em>) can inflict painful bites upon people and livestock.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/horse-fly-hybomitra-epistates-portrait-1773555527">Mircea Costina/Shutterstock</a></span>
</figcaption>
</figure>
<p>Of course, artificial neural networks are not real flies, nor exact models of a fly’s nervous system. But they do show us the most efficient way of processing a fly’s visual signals to identify natural stimuli. And we expect evolution to have taken advantage of similar principles in real fly nervous systems.</p>
<p>The best way to identify shade using the visual information a fly has is through brightness and not blueness. Meanwhile, the best way of identifying animals was, somewhat counterintuitively, using blueness. Such a mechanism is very strongly stimulated by blue traps, explaining why they prove such a powerful lure for hungry flies. Further evidence for this idea comes from field studies which show that tsetse landing on coloured traps are <a href="https://resjournals.onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-3032.1990.tb00519.x">relatively starved</a>.</p>
<p>If we can understand the sensory signals and behaviour that cause flies to be caught in traps, we can engineer traps to more efficiently exploit those mechanisms and more effectively control the flies. We’ve already had <a href="https://journals.plos.org/plosntds/article?id=10.1371%2Fjournal.pntd.0007905#:%7E:text=Tsetse%20can%20be%20controlled%20using%20insecticide-treated%20fabric%20targets%2C,these%20fabrics%20to%20be%20more%20attractive%20to%20tsetse.">some success</a> in doing this for tsetse flies.</p>
<p>More effective traps will help minimise the impacts of those flies on health and welfare of people and animals. They could help prevent the damaging effects of biting flies on livestock, help in the fight against dangerous fly-borne diseases such as <a href="https://www.who.int/news-room/fact-sheets/detail/trypanosomiasis-human-african-(sleeping-sickness)">sleeping sickness</a>, and protect us and animals from fly attacks in general.</p><img src="https://counter.theconversation.com/content/208639/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Roger Santer has received funding from the Knowledge Economy Skills Scholarships program, and from the Centre for International Development Research at Aberystwyth (CIDRA). </span></em></p>New research on what attracts blood-feasting flies to blue objects could help minimise the impacts of those insects on people and animals.Roger Santer, Lecturer in Zoology, Aberystwyth UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2038372023-05-17T12:39:23Z2023-05-17T12:39:23ZBees can learn, remember, think and make decisions – here’s a look at how they navigate the world<figure><img src="https://images.theconversation.com/files/526312/original/file-20230515-24407-1yxhj8.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C2286%2C1560&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A bumblebee lands on the flowers of a white sloe bush. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/april-2022-saxony-anhalt-kathendorf-a-bumblebee-lands-on-news-photo/1240227459">Soeren Stache/picture alliance via Getty Images</a></span></figcaption></figure><p>As trees and flowers blossom in spring, bees emerge from their winter nests and burrows. For many species it’s <a href="https://theconversation.com/spring-signals-female-bees-to-lay-the-next-generation-of-pollinators-134852">time to mate</a>, and some will start new solitary nests or colonies. </p>
<p>Bees and other pollinators are essential to human society. They provide about one-third of the <a href="https://theconversation.com/a-bee-economist-explains-honey-bees-vital-role-in-growing-tasty-almonds-101421">food we eat</a>, a service with a global value estimated at <a href="https://doi.org/10.1038/nature20588">up to $US577 billion annually</a>.</p>
<p>But bees are interesting in many other ways that are less widely known. In my new book, “<a href="https://islandpress.org/books/what-bee-knows">What a Bee Knows: Exploring the Thoughts, Memories, and Personalities of Bees</a>,” I draw on my experience <a href="https://scholar.google.com/citations?user=tqms8REAAAAJ&hl=en">studying bees for almost 50 years</a> to explore how these creatures perceive the world and their amazing abilities to navigate, learn, communicate and remember. Here’s some of what I’ve learned.</p>
<h2>It’s not all about hives and honey</h2>
<p>Because people are widely familiar with honeybees, many assume that all bees are social and live in hives or colonies with a queen. In fact, only about 10% of bees are social, and most types don’t make honey.</p>
<p>Most bees lead solitary lives, digging nests in the ground or finding abandoned beetle burrows in dead wood to call home. Some bees are cleptoparasites, <a href="https://www.sciencefriday.com/articles/death-and-thievery-in-the-colony/">sneaking into unoccupied nests to lay eggs</a>, in the same way that cowbirds lay their eggs in other birds’ nests and let the unknowing foster parents <a href="https://madisonaudubon.org/blog/2018/8/9/into-the-nest-cowbirds-everybodys-favorite-villain">rear their chicks</a>.</p>
<p>A few species of tropical bees, known as vulture bees, survive by <a href="https://doi.org/10.1128/mBio.02317-21">eating carrion</a>. Their guts contain acid-loving bacteria that enable the bees to digest rotting meat. </p>
<p><div data-react-class="InstagramEmbed" data-react-props="{"url":"https://www.instagram.com/p/CGWgbHdgmBB/?utm_source=ig_web_copy_link\u0026igshid=MzRlODBiNWFlZA==","accessToken":"127105130696839|b4b75090c9688d81dfd245afe6052f20"}"></div></p>
<h2>Busy brains</h2>
<p>The world looks very different to a bee than it does to a human, but bees’ perceptions are hardly simple. Bees are intelligent animals that <a href="https://doi.org/10.1016/j.anbehav.2016.05.005">likely feel pain</a>, remember patterns and odors and even <a href="https://doi.org/10.1242/jeb.01929">recognize human faces</a>. They <a href="https://doi.org/10.1006/nlme.1996.0069">can solve mazes</a> and other problems and use simple tools. </p>
<p>Research shows that bees <a href="https://doi.org/10.1016/j.cub.2020.12.027">are self-aware</a> and may even have a <a href="https://doi.org/10.1016/j.cub.2017.08.008">primitive form of consciousness</a>. During the six to 10 hours bees spend <a href="https://doi.org/10.7717/peerj.9583">sleeping daily</a>, <a href="https://doi.org/10.1016/j.neubiorev.2014.09.020">memories are consolidated</a> within their amazing brains – organs the size of a poppy seed that contain 1 million nerve cells. There are some indications that <a href="https://doi.org/10.1016/j.cub.2015.09.001">bees might even dream</a>. I’d like to think so. </p>
<h2>An alien sensory world</h2>
<p>Bees’ sensory experience of the world is markedly different from ours. For example, humans see the world through the primary colors of <a href="http://hyperphysics.phy-astr.gsu.edu/hbase/vision/colcon.html">red, green and blue</a>. Primary colors for bees are <a href="https://doi.org/10.1007/978-3-642-71496-2_15">green, blue and ultraviolet</a>.</p>
<p>Bees’ vision is <a href="https://doi.org/10.1146/annurev.ento.010908.164537">60 times less sharp than that of humans</a>: A flying bee can’t see the details of a flower until it is about 10 inches away. However, bees can see hidden ultraviolet floral patterns that are invisible to us, and those patterns lead the bees to flowers’ nectar.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/kQ8GRJp8bVg?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Naturalist David Attenborough uses ultraviolet light to show how flowers may appear different to bees than to humans.</span></figcaption>
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<p>Bees also can spot flowers by detecting color changes at a distance. When humans watch film projected at 24 frames per second, the individual images appear to blur into motion. This phenomenon, which is called the <a href="https://www.britannica.com/science/movement-perception/Apparent-movement#ref488126">flicker-fusion frequency</a>, indicates how capable our visual systems are at resolving moving images. Bees have a much higher flicker-fusion frequency – you would have to play the film 10 times faster for it to look like a blur to them – so they can fly over a flowering meadow and <a href="https://doi.org/10.1007/BF00610583">see bright spots of floral color</a> that wouldn’t stand out to humans.</p>
<p>From a distance, bees detect flowers by scent. A honeybee’s sense of smell is <a href="https://doi.org/10.1371/journal.pone.0009110">100 times more sensitive</a> than ours. Scientists have used bees to sniff out chemicals <a href="https://entomologytoday.org/2013/11/25/can-trained-bees-detect-cancer-in-patients/">associated with cancer</a> and <a href="https://www.cbsnews.com/boston/news/boston-researchers-train-bees-to-detect-diabetes/">with diabetes</a> on patients’ breath and to detect the presence of <a href="https://www.technologyreview.com/2006/12/07/227361/using-bees-to-detect-bombs/">high explosives</a>. </p>
<p>Bees’ sense of touch is also highly developed: They can feel tiny fingerprint-like ridges <a href="https://doi.org/10.1073/pnas.82.14.4750">on the petals of some flowers</a>. Bees are <a href="https://doi.org/10.1080/0005772X.1995.11099233">nearly deaf</a> to most airborne sounds, unless they are very close to the source, but are sensitive if they are standing on a vibrating surface. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1348645052134944771"}"></div></p>
<h2>Problem solvers</h2>
<p>Bees <a href="https://doi.org/10.1080/0005772X.1995.11099233">can navigate mazes</a> as well as mice can, and studies show that they are self-aware of their body dimensions. For example, when fat bumblebees were trained to fly and then walk through a slit in a board to get to food on the other side, the bees <a href="https://doi.org/10.1073/pnas.2016872117">turned their bodies sideways and tucked in their legs</a>. </p>
<p>Experiments by Canadian researcher Peter Kevan and Lars Chittka in England demonstrated remarkable feats of bee learning. Bumblebees were trained to pull a string – in other words, to use a tool – connected to a plastic disk with hidden depressions filled with sugar water. They could see the sugar wells but couldn’t get the reward <a href="https://doi.org/10.1371/journal.pbio.1002564">except by tugging at the string</a> until the disk was uncovered.</p>
<p>Other worker bees were placed nearby in a screen cage where they could see what their trained hive mates did. Once released, this second group also pulled the string for the sweet treats. This study demonstrated what scientists term <a href="https://www.britannica.com/science/social-learning">social learning</a> – acting in ways that reflect the behavior of others.</p>
<h2>Pollinating with vibrations</h2>
<p>Even pollination, one of bees’ best-known behaviors, can be much more complicated than it seems. </p>
<p>The basic process is similar for all types of bees: Females carry pollen grains, the sex cells of plants, on their bodies from flower to flower as they collect pollen and nectar to feed themselves and their developing grubs. When pollen rubs off onto <a href="https://www.amnh.org/learn-teach/curriculum-collections/biodiversity-counts/plant-identification/plant-morphology/parts-of-a-flower">a flower’s stigma</a>, the result is pollination. </p>
<p>My favorite area of bee research examines a method called <a href="https://doi.org/10.1016/j.pbi.2013.05.002">buzz pollination</a>. Bees use it on about 10% of the world’s 350,000 kinds of flowering plants that have special <a href="https://www.amnh.org/learn-teach/curriculum-collections/biodiversity-counts/plant-identification/plant-morphology/parts-of-a-flower">anthers</a> – structures that produce pollen. </p>
<p>For example, a tomato blossom’s five anthers are pinched together, like the closed fingers of one hand. Pollen is released through one or two small pores at the end of each anther. </p>
<p>When a female bumblebee lands on a tomato flower, she bites one anther at the middle and contracts her flight muscles from <a href="https://doi.org/10.1093/jxb/erab428">100 to 400 times per second</a>. These powerful vibrations eject pollen from the anther pores in the form of a cloud that strikes the bee. It all happens in just a few tenths of a second. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/SZrTndD1H10?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Bumblebees demonstrate buzz pollination on a Persian violet blossom.</span></figcaption>
</figure>
<p>The bee hangs by one leg and scrapes the pollen into “baskets” – structures on her hind legs. Then she repeats the buzzing on the remaining anthers before moving to different flowers.</p>
<p>Bees also use buzz pollination on the flowers of blueberries, cranberries, eggplant and kiwi fruits. My colleagues and I are conducting experiments to determine the biomechanics of <a href="https://doi.org/10.1098/rsif.2022.0040">how bee vibrations eject pollen from anthers</a>. </p>
<h2>Planting for bees</h2>
<p>Many species of bees are <a href="https://theconversation.com/bees-face-many-challenges-and-climate-change-is-ratcheting-up-the-pressure-190296">declining worldwide</a>, thanks to stresses including <a href="http://dx.doi.org/%2010.1126/science.1255957">parasites, pesticides and habitat loss</a>.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/526311/original/file-20230515-18664-v796la.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Wood cubes filled with twigs and bricks." src="https://images.theconversation.com/files/526311/original/file-20230515-18664-v796la.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/526311/original/file-20230515-18664-v796la.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/526311/original/file-20230515-18664-v796la.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/526311/original/file-20230515-18664-v796la.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/526311/original/file-20230515-18664-v796la.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/526311/original/file-20230515-18664-v796la.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/526311/original/file-20230515-18664-v796la.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>
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<span class="caption">A backyard ‘insect hotel’ for solitary bees and other nesting insects, made from stems, bricks and wood blocks.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/insect-hotel-for-solitary-bees-and-artificial-nesting-place-news-photo/601067110">Arterra/Universal Images Group vis Getty Images</a></span>
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<p>Whether you have an apartment window box or several acres of land, you can do a few <a href="https://theconversation.com/to-help-insects-make-them-welcome-in-your-garden-heres-how-153609">simple things to help bees</a>. </p>
<p>First, plant native wildflowers so that blooms are available in every season. Second, try to avoid using insecticides or herbicides. Third, provide open ground where burrowing bees can nest. With luck, soon you’ll have some buzzing new neighbors.</p><img src="https://counter.theconversation.com/content/203837/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Stephen Buchmann 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>Scientists are learning amazing things about bees’ sensory perception and mental capabilities.Stephen Buchmann, Adjunct Professor of Entomology and of Ecology and Evolutionary Biology, University of ArizonaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2030962023-04-05T13:53:51Z2023-04-05T13:53:51ZEaster bunnies, cacao beans and pollinating bugs: A basket of 6 essential reads about chocolate<figure><img src="https://images.theconversation.com/files/519391/original/file-20230404-14-reloqo.jpg?ixlib=rb-1.1.0&rect=422%2C0%2C4914%2C3173&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Easter has its bunnies, but chocolate comes out for every holiday.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/chocolate-bunny-family-royalty-free-image/177875356">garytog/iStock via Getty Images Plus</a></span></figcaption></figure><p><a href="https://www.insider.com/surprising-easter-fun-facts-stats-2019-4#as-many-as-91-million-chocolate-bunnies-are-sold-in-the-us-for-easter-annually-8">Tens of millions of chocolate bunnies</a> get sold in the U.S. every Easter. Here are six articles about chocolate from The Conversation’s archive – great reading while you’re nibbling the ears off your own bunny (if you’re one of the <a href="https://www.insider.com/surprising-easter-fun-facts-stats-2019-4#as-many-as-78-of-americans-eat-the-ears-of-their-chocolate-bunny-first-11">three-quarters of Americans who start</a> at the top).</p>
<h2>1. Food scientist on cocoa chemistry</h2>
<p>Chocolate bunnies don’t grow on trees – but cacao pods do. It takes a lot of processing to get from the raw agricultural input to the finished output.</p>
<p>Food scientist <a href="https://scholar.google.com/citations?user=5iZjEckAAAAJ&hl=en&oi=ao">Sheryl Barringer</a> from The Ohio State University wrote about various chemical reactions that are part of the transformation of beans into chocolate. One is the Maillard reaction, the same thing that gives the browned bits on roasted meats or a bread’s golden crust their flavor. <a href="https://theconversation.com/chocolate-chemistry-a-food-scientist-explains-how-the-beloved-treat-gets-its-flavor-texture-and-tricky-reputation-as-an-ingredient-198222">Barringer also explains that weird white stuff</a> – known as bloom – that might appear on your Easter chocolates if they hang around for a while. (Don’t worry, it’s still edible.)</p>
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Read more:
<a href="https://theconversation.com/chocolate-chemistry-a-food-scientist-explains-how-the-beloved-treat-gets-its-flavor-texture-and-tricky-reputation-as-an-ingredient-198222">Chocolate chemistry – a food scientist explains how the beloved treat gets its flavor, texture and tricky reputation as an ingredient</a>
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<h2>2. Chocolate is a fermented food</h2>
<p>Food science Ph.D. candidate <a href="https://scholar.google.com/citations?user=QjIM6yUAAAAJ&hl=en&oi=ao">Caitlin Clark</a> from Colorado State University focuses her research on the microbes responsible for much of chocolate’s flavor. As a fermented food, chocolate depends on yeast and bacteria to help turn a raw ingredient into the treat you can recognize.</p>
<p>Clark described how the microorganisms that occur naturally in a given geographical location can give high-end chocolates their “terroir” – “<a href="https://theconversation.com/chocolates-secret-ingredient-is-the-fermenting-microbes-that-make-it-taste-so-good-155552">the characteristic flair imparted by a place</a>” you might be more used to thinking about with regard to wine.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/chocolates-secret-ingredient-is-the-fermenting-microbes-that-make-it-taste-so-good-155552">Chocolate's secret ingredient is the fermenting microbes that make it taste so good</a>
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<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/519395/original/file-20230404-2112-yh79aj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Cacao pods and flowers on branch tree close up" src="https://images.theconversation.com/files/519395/original/file-20230404-2112-yh79aj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/519395/original/file-20230404-2112-yh79aj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/519395/original/file-20230404-2112-yh79aj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/519395/original/file-20230404-2112-yh79aj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/519395/original/file-20230404-2112-yh79aj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/519395/original/file-20230404-2112-yh79aj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/519395/original/file-20230404-2112-yh79aj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&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">Tiny flies spread pollen from one cacao tree to another.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/cacao-pods-and-flower-on-branch-royalty-free-image/1165785501">dimarik/iStock via Getty Images Plus</a></span>
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<h2>3. Pollinators are important part of process</h2>
<p>Cacao growers rely on another tiny ally to pollinate their crop. Entomologist <a href="https://scholar.google.com/citations?hl=en&user=qvmWZYwAAAAJ">DeWayne Shoemaker</a> from the University of Tennessee described the mini flies – particularly biting midges and gall midges – that get the job done. “Pollinators must pick up pollen from the male parts of a flower of one tree and deposit it on the female parts of a flower on another tree,” Shoemaker wrote.</p>
<p>But up to <a href="https://theconversation.com/tiny-cacao-flowers-and-fickle-midges-are-part-of-a-pollination-puzzle-that-limits-chocolate-production-154334">90% of cacao flowers don’t get pollinated</a> at all. People can hand-pollinate the little flowers, but it remains a mystery which other insects might do the job in the wild.</p>
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Read more:
<a href="https://theconversation.com/tiny-cacao-flowers-and-fickle-midges-are-part-of-a-pollination-puzzle-that-limits-chocolate-production-154334">Tiny cacao flowers and fickle midges are part of a pollination puzzle that limits chocolate production</a>
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<h2>4. Child labor is chocolate’s bitter secret</h2>
<p>Harvesting and processing cacao is labor-intensive. To meet this need, some farmers turn to child labor. Cultural anthropologist <a href="https://scholar.google.com/citations?user=1ErMxzgAAAAJ&hl=en&oi=ao">Robert Ulin</a> from the Rochester Institute of Technology described how the global chocolate industry is tied to inequality via exploitative labor practices.</p>
<p>“The largest chocolate companies signed a protocol in 2001 that <a href="https://theconversation.com/some-chocolate-has-a-dark-side-to-it-child-labor-179271">condemned child labor and childhood slavery</a>,” Ulin wrote. But he noted that consumers may want more information to make sure their purchase power supports “fair labor practices in the chocolate sector.” </p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/some-chocolate-has-a-dark-side-to-it-child-labor-179271">Some chocolate has a dark side to it – child labor</a>
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<a href="https://images.theconversation.com/files/519398/original/file-20230404-18-7hqbi6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Dog and woman, both with Easter bunny ears on" src="https://images.theconversation.com/files/519398/original/file-20230404-18-7hqbi6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/519398/original/file-20230404-18-7hqbi6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/519398/original/file-20230404-18-7hqbi6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/519398/original/file-20230404-18-7hqbi6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/519398/original/file-20230404-18-7hqbi6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/519398/original/file-20230404-18-7hqbi6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/519398/original/file-20230404-18-7hqbi6.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>
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<span class="caption">Do not share your chocolates with your pooch.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/dog-and-woman-with-costume-and-easter-decorations-royalty-free-image/1359250422">F.J. Jimenez/Moment via Getty Images</a></span>
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<h2>5. Not safe for furry family members</h2>
<p>Eating a ton of chocolate is probably not a healthy choice for anyone. But even a little bit of chocolate can be deadly for dogs and cats. </p>
<p>In an article about all kinds of holiday foods that are unsafe for pets, veterinarian and researcher <a href="https://experts.okstate.edu/le.fanucchi">Leticia Fanucchi</a> from Oklahoma State University explained the chemicals in this human delicacy that can cause fatal “<a href="https://theconversation.com/holiday-foods-can-be-toxic-to-pets-a-veterinarian-explains-which-and-what-to-do-if-rover-or-kitty-eats-them-196453">chocolate intoxication</a>.” Don’t delay getting veterinary help if your pet does raid your Easter basket.</p>
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Read more:
<a href="https://theconversation.com/holiday-foods-can-be-toxic-to-pets-a-veterinarian-explains-which-and-what-to-do-if-rover-or-kitty-eats-them-196453">Holiday foods can be toxic to pets – a veterinarian explains which, and what to do if Rover or Kitty eats them</a>
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<h2>6. An enslaved chocolatier in colonial America</h2>
<p>An enslaved cook named Caesar, born in 1732, was one of the first chocolatiers in the American colonies. Historical archaeologist <a href="https://berkeley.academia.edu/KelleyFantoDeetz">Kelley Fanto Deetz</a> from the University of California, Berkeley described how Caesar “would have had to <a href="https://theconversation.com/oppression-in-the-kitchen-delight-in-the-dining-room-the-story-of-caesar-an-enslaved-chef-and-chocolatier-in-colonial-virginia-151356">roast the cocoa beans on the open hearth</a>, shell them by hand, grind the nibs on a heated chocolate stone, and then scrape the raw cocoa, add milk or water, cinnamon, nutmeg or vanilla, and serve it piping hot.”</p>
<p>Cocoa was a hot commodity for Virginia’s white elite during this period, when it was a culinary component – along with pineapples, Madeira wine, port, champagne, coffee and sugar – of the Columbian Exchange.</p>
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Read more:
<a href="https://theconversation.com/oppression-in-the-kitchen-delight-in-the-dining-room-the-story-of-caesar-an-enslaved-chef-and-chocolatier-in-colonial-virginia-151356">Oppression in the kitchen, delight in the dining room: The story of Caesar, an enslaved chef and chocolatier in Colonial Virginia</a>
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<p><em>Editor’s note: This story is a roundup of articles from The Conversation’s archives.</em></p><img src="https://counter.theconversation.com/content/203096/count.gif" alt="The Conversation" width="1" height="1" />
Two food scientists, an entomologist, an anthropologist, a veterinarian and a historian walk into a bar (of chocolate) and tell bitter and sweet stories of this favorite treat.Maggie Villiger, Senior Science + Technology EditorLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1998262023-02-15T12:21:43Z2023-02-15T12:21:43ZInsects are vanishing worldwide – now it’s making it harder to grow food<figure><img src="https://images.theconversation.com/files/510040/original/file-20230214-28-nfrfs.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C5657%2C3799&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/young-green-corn-growing-on-field-2012418830">Catherine_P/Shutterstock</a></span></figcaption></figure><p>Over the past 20 years a steady trickle of scientific papers has reported that there are fewer insects than there used to be. Both the combined weight (what scientists call biomass) and diversity of insect species have declined. Some studies were based on sightings by amateur entomologists, while others involved scientists counting the number of bugs splattered on car windshields. Some collected flying insects in traps annually for years and weighed them.</p>
<p>In the past six years, this trickle has become a flood, with more and more sophisticated studies confirming that although not all insect species are declining, many are in serious trouble. A 2020 <a href="https://www.science.org/doi/10.1126/science.aax9931">compilation</a> of 166 studies estimated that insect populations were on average declining globally at a rate of 0.9% per year. But the declines are uneven. Even within the same environments, populations of some insect species have waned, while others have remained stable and still some others increased. The reasons for these differences between insects are unknown, though evidently some are more resilient than others.</p>
<p>Until recently, much of the evidence has been drawn from protected areas in Europe and to a lesser extent North America. So what is the picture like elsewhere? <a href="https://www.science.org/doi/10.1126/sciadv.ade9341">A new study</a> offers fresh data on the seasonal migrations of insects in east Asia. These insects, many of them pest species, fly north in spring every year to take advantage of the new growing season, and fly south in autumn to escape the cold.</p>
<figure class="align-center ">
<img alt="A sky filled with monarch butterflies." src="https://images.theconversation.com/files/510041/original/file-20230214-24-2yjxp1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/510041/original/file-20230214-24-2yjxp1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=382&fit=crop&dpr=1 600w, https://images.theconversation.com/files/510041/original/file-20230214-24-2yjxp1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=382&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/510041/original/file-20230214-24-2yjxp1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=382&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/510041/original/file-20230214-24-2yjxp1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=481&fit=crop&dpr=1 754w, https://images.theconversation.com/files/510041/original/file-20230214-24-2yjxp1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=481&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/510041/original/file-20230214-24-2yjxp1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=481&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Insects can travel thousands of miles in seasonal migrations.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/monarch-butterfly-biosphere-reserve-michoacan-mexico-1786064138">Javarman/Shutterstock</a></span>
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</figure>
<p>A progressive fall in the enormous numbers of these migrants indicates that insect declines are indeed a global problem.</p>
<h2>Millions of migrating insects</h2>
<p>Between 2003 and 2020, scientists from the Chinese Academy of Agricultural Sciences in Beijing caught almost 3 million migrating insects from high-altitude searchlight traps on Beihuang Island off the coast of northeast China. A further 9 million insects were detected from radar records. In all, 98 species were identified and counted, most of which were either plant-eating crop pests or insects that are their natural enemies – predators and parasites. Over the whole 18-year period, the yearly tally of all identified insects fell by 7.6%, a steady downward trend of 0.4% a year.</p>
<p>Insect declines clearly are occurring on a large scale in Asia, just as they have been in Europe and North America. It seems reasonable to assume that the causes are the same. Although we don’t know for certain what those causes are, it seems likely that they operate all over the world.</p>
<p>The study also showed that pest insects such as the black cutworm moth, whose caterpillars attack a wide variety of vegetable crops, are as strongly affected by the global decline of insects as non-pest species such as bees and butterflies that were the subjects of most of the previous European and American studies.</p>
<p>We are so used to considering insects as pests that it is tempting to think that, in a world with fewer of them, agriculture might prosper as never before. This new study reveals why that is not the case. The researchers used detailed entomological records from the past to construct a complex food web showing how each of the insect pest species caught in the searchlight traps can be eaten by several kinds of insect predators and parasites, often termed “natural enemies”. As an example, black cutworm caterpillars are eaten by green lacewings, among others. </p>
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<img alt="A long, green insect with curved, transparent wings and small, red eyes." src="https://images.theconversation.com/files/510043/original/file-20230214-22-5s7zav.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/510043/original/file-20230214-22-5s7zav.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/510043/original/file-20230214-22-5s7zav.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/510043/original/file-20230214-22-5s7zav.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/510043/original/file-20230214-22-5s7zav.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/510043/original/file-20230214-22-5s7zav.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/510043/original/file-20230214-22-5s7zav.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">Green lacewings eat crop pests – but there are fewer of them in farm fields.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/extreme-magnification-lacewing-pest-control-465774065">Cornel Constantin/Shutterstock</a></span>
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<p>The researchers compared how fast 124 pests had declined alongside each of their natural enemies. Over the 18-year study, the abundance of natural enemy species fell at a rate of 0.65% a year, while the plant-eating prey did not decrease in number at all, on average. This suggests that beneficial natural enemy species are more likely to decline than the pests that they feed on. As a result, farmers must either tolerate lower crop yields or use even more chemical insecticides to control pests, leading to still worse declines.</p>
<p>Although it is tempting to point a finger at <a href="https://theconversation.com/a-common-soil-pesticide-cut-wild-bee-reproduction-by-89-heres-why-scientists-are-worried-155985">pesticides</a>, <a href="https://theconversation.com/why-the-changing-colour-of-our-streetlights-could-be-a-danger-for-insect-populations-166470">bright streetlights</a> or <a href="https://theconversation.com/climate-change-triggering-global-collapse-in-insect-numbers-stressed-farmland-shows-63-decline-new-research-170738">climate change</a>, insect declines almost certainly have multiple causes that overlap. </p>
<p>The most frequently named suspect is agricultural intensification. This term covers a multitude of sins. Farm mechanisation, the eradication of hedges, crop monocultures, the increased use of chemical fertilisers and regular applications of pesticides are all intended to produce fields without weeds, pests or diseases. Only a reduced range of wild plants and animals can survive in the narrow field margins and neighbouring roadside verges that remain. Another way of putting it is that farmers have made fields unwelcoming to most insects.</p>
<p>Intensification is designed to ensure that as much as possible of the farm ecosystem’s energy flow is diverted into growing crops and livestock for human consumption. It has been estimated that <a href="https://www.pnas.org/doi/full/10.1073/pnas.0704243104">24% of all plant growth</a> annually is now appropriated by humans, and this rises to a staggering 69% on cropland. These figures roughly doubled over the 20th century. It’s no wonder that insects don’t do well in landscapes such as these, and farmland occupies <a href="https://www.fao.org/sustainability/news/detail/en/c/1274219/">almost 40%</a> of the land.</p>
<h2>Why you’ll miss bugs</h2>
<p>Insects are by far the most numerous of all animals on Earth. The estimated <a href="https://www.science.org/doi/10.1126/sciadv.abq4049#">global total</a> of new insect material that grows each year is an astonishing 1,500 million tonnes. Most of this is immediately consumed by an upward food chain of predators and parasites, so that the towering superstructure of all the Earth’s animal diversity is built on a foundation of insects and their arthropod relatives.</p>
<p>If insects decline, then other wild animals must inevitably decline too. There is already evidence that this is happening. In North America, insect-eating bird species experienced an <a href="https://academic.oup.com/condor/article/123/1/duaa059/6063623">average decline in population size</a> of almost 10 million over the past 50 years, while those for which insects are not essential prey did not decline at all. In Europe, parallel declines of insectivorous swallows, house martins and swifts have all been <a href="https://avianres.biomedcentral.com/articles/10.1186/s40657-021-00278-1">linked to insect declines</a>.</p>
<p>While it’s true that a few insects are a menace to humans (disease-carrying mosquitoes come to mind), the vast majority of insects are friendly: they pollinate crops, provide natural pest control, recycle nutrients and form soil by aiding the decomposition of dead animals and plants. All these processes will slow down if insects become scarce. The economic value of these services is incalculable – agriculture could not continue for long without them.</p>
<p>Our insect friends are being crowded out. Somehow, we must find ways to make more room for them.</p>
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<img alt="Imagine weekly climate newsletter" src="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?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">
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<p class="fine-print"><em><span>Stuart Reynolds 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 from China shows how the loss of insects is destabilising food webs.Stuart Reynolds, Emeritus Professor of Biology, University of BathLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1917712023-01-23T00:06:24Z2023-01-23T00:06:24ZDon’t kill the curl grubs in your garden – they could be native beetle babies<figure><img src="https://images.theconversation.com/files/501433/original/file-20221215-19-5mtmdl.jpg?ixlib=rb-1.1.0&rect=6%2C165%2C4594%2C3283&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>Have you ever been in the garden and found a large, white, C-shaped grub with a distinctive brown head and six legs clustered near the head? </p>
<p>If so, you’ve had an encounter with the larva of a scarab beetle (family: <em>Scarabaeidae</em>) also known as a “curl grub”. </p>
<p>Many gardeners worry these large larvae might damage plants. </p>
<p>So what are curl grubs? And should you be concerned if you discover them in your garden?</p>
<h2>What are curl grubs?</h2>
<p>Curl grubs turn into scarab beetles.</p>
<p>There are more than 30,000 species of scarab beetles worldwide. Australia is home to at least 2,300 of these species, including iridescent Christmas beetles (<a href="https://australian.museum/learn/animals/insects/christmas-beetle/"><em>Anoplognathus</em></a>), spectacularly horned rhinoceros beetles (<em>Dynastinae</em>), and the beautifully patterned flower chafers (<a href="https://keys.lucidcentral.org/keys/v3/aus_museum/flower_chafers/key/Cetoniinae/Media/Html/key.htm"><em>Cetoniinae</em></a>). </p>
<p>While the adults might be the most conspicuous life stage, scarabs spend most of their lives as larvae, living underground or in rotting wood. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/499922/original/file-20221209-25133-p3m533.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A bird holds a curl grub in its beak." src="https://images.theconversation.com/files/499922/original/file-20221209-25133-p3m533.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/499922/original/file-20221209-25133-p3m533.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/499922/original/file-20221209-25133-p3m533.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/499922/original/file-20221209-25133-p3m533.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/499922/original/file-20221209-25133-p3m533.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/499922/original/file-20221209-25133-p3m533.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/499922/original/file-20221209-25133-p3m533.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">Curl grubs make an excellent meal for hungry birds.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Scarab larvae can help the environment</h2>
<p>Soil-dwelling scarab larvae can aerate soils and help <a href="https://www-sciencedirect-com.ezproxy.library.sydney.edu.au/science/article/pii/S0006320708001420">disperse</a> seeds. </p>
<p>Species that eat decaying matter help recycle nutrients and keep soils healthy. </p>
<p>Most scarab larvae are large and <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4684676/">full of protein and fat</a>. They make an excellent meal for <a href="https://deepgreenpermaculture.com/2018/08/12/organic-control-of-curl-grubs-in-lawn/#:%7E:text=The%20most%20useful%20natural%20enemies,digging%20them%20out%20of%20lawns.">hungry birds</a>.</p>
<p>Besides being important for ecosystems, scarabs also play a role in <a href="https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1093&context=entomologypapers">cultural celebrations</a>.</p>
<p>For example, the ancient Egyptians famously worshipped the sun through the symbol of the ball-rolling dung beetle. </p>
<p>In Australia, colourful Christmas beetles traditionally heralded the arrival of the holiday season. </p>
<p>Sadly, Christmas beetle numbers have <a href="https://australian.museum/learn/animals/insects/christmas-beetles/">declined</a> over the last few decades, likely due to habitat loss. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1332262556560453632"}"></div></p>
<h2>Are the curl grubs in my garden harming my plants?</h2>
<p>Most scarab larvae feed on grass roots, and this can cause damage to plants when there’s a lot of them.</p>
<p>In Australia, the <a href="https://inaturalist.ala.org.au/taxa/517487-Cyclocephala-signaticollis">Argentine lawn scarab</a> and the <a href="https://www.agric.wa.gov.au/olives/african-black-beetle-horticulture">African black beetle</a> are invasive pest species that cause significant damage to pastures and lawns. </p>
<p>Native scarab species can also be pests under the right circumstances.</p>
<p>For example, when Europeans began planting sugar cane (a type of grass) and converting native grasslands to pastures, many native Australian scarab species found an abundant new food source and were subsequently classified as <a href="https://www.mdpi.com/2075-4450/11/1/54/htm">pests</a>.</p>
<p>Unfortunately, we know little about the feeding habits of many native scarab larvae, including those found in gardens.</p>
<p>Some common garden species, like the beautifully patterned <a href="https://australian.museum/learn/animals/insects/fiddler-beetle/">fiddler beetle</a> (<em>Eupoecila australasiae</em>), feed on decaying wood and are unlikely to harm garden plants. </p>
<p>Even species that consume roots are likely not a problem under normal conditions. </p>
<p>Plants are surprisingly <a href="https://link.springer.com/article/10.1007/s00442-011-2210-y">resilient</a>, and most can handle losing a small number of their roots to beetle larvae. Even while damaging plants, curl grubs may be helping keep soil healthy by providing aeration and nutrient mixing.</p>
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Read more:
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</strong>
</em>
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<hr>
<figure class="align-center ">
<img alt="manicured grass and garden" src="https://images.theconversation.com/files/502386/original/file-20221221-18-bs2txf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/502386/original/file-20221221-18-bs2txf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/502386/original/file-20221221-18-bs2txf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/502386/original/file-20221221-18-bs2txf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/502386/original/file-20221221-18-bs2txf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/502386/original/file-20221221-18-bs2txf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/502386/original/file-20221221-18-bs2txf.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">Most plants can handle losing a small number of their roots to beetle larvae.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>How do I know if I have ‘good’ or ‘bad’ beetle larvae in my garden?</h2>
<p>Unfortunately, identifying scarab larvae species is challenging. Many of the features we use to tell groups apart are difficult to see without magnification.
While there are identification guides for scarabs larvae found in <a href="https://cesaraustralia.com/pestfacts/scarabs-and-cockchafers-identification/">pastures</a>, there are currently no such identification resources for the scarabs found in household gardens. </p>
<p>Since identification may not be possible, the best guide to whether or not scarab larvae are a problem in your garden is the health of your plants. Plants with damaged roots may wilt or turn yellow. </p>
<p>Since most root-feeding scarabs prefer grass roots, lawn turf is most at risk and damage is usually caused by exotic scarab species.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/501443/original/file-20221215-14-rbzlz0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/501443/original/file-20221215-14-rbzlz0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/501443/original/file-20221215-14-rbzlz0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/501443/original/file-20221215-14-rbzlz0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/501443/original/file-20221215-14-rbzlz0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/501443/original/file-20221215-14-rbzlz0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/501443/original/file-20221215-14-rbzlz0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/501443/original/file-20221215-14-rbzlz0.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">Unfortunately, identifying scarab larvae species is challenging.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>What should I do if I find curl grubs in my garden?</h2>
<p>Seeing suspiciously plump curl grubs amongst the roots of prized garden plants can be alarming, but please don’t automatically reach for insecticides. </p>
<p>The chemicals used to control curl grubs will harm all scarab larvae, regardless of whether or not they are pests. </p>
<p>Many of the most common treatments for curl grubs contain chemicals called “anthranilic diamides”, which are also <a href="http://npic.orst.edu/factsheets/chlorantraniliprole.html#howwork">toxic</a> to butterflies, moths and aquatic invertebrates.</p>
<p>And by disrupting soil ecosystems, using insecticides might do more harm than good and could kill harmless native beetle larvae.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-has-my-home-been-overrun-by-pantry-moths-and-how-do-i-get-rid-of-them-an-expert-explains-170274">Why has my home been overrun by pantry moths and how do I get rid of them? An expert explains</a>
</strong>
</em>
</p>
<hr>
<p>So what to do instead? </p>
<p>Larvae found in decaying wood or mulch are wood feeders and are useful composters; they will not harm your plants and should be left where they are. </p>
<p>Larvae found in compost bins are helping to break down wastes and should also be left alone.</p>
<p>If you find larvae in your garden soil, use your plant’s health as a guide. If your plants appear otherwise healthy, consider simply leaving curl grubs where they are. Scarab larvae are part of the soil ecosystem and are unlikely to do damage if they are not present in high numbers. </p>
<p>If your plants appear yellow or wilted and you’ve ruled out other causes, such as under-watering or nutrient deficiencies, consider feeding grubs to the birds or squishing them. It’s not nice, but it’s better than insecticides.</p>
<p>Lawns are particularly susceptible to attack by the larvae of non-native scarabs.
Consider replacing lawns with <a href="https://www.sgaonline.org.au/lawn-alternatives/">native</a> ground covers. This increases biodiversity and lowers the chances of damage from non-native scarab larvae.</p>
<p>Scarab beetles are beautiful and fascinating insects that help keep our soils healthy and our wildlife well fed.</p><img src="https://counter.theconversation.com/content/191771/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tanya Latty volunteers for and is affiliated with Invertebrates Australia, a not for profit conservation organisation. She is also affiliated with the Australian Entomological Society and the Australasian Society for the Study of Animal Behaviour. She receives funding from the Australian Research Council</span></em></p><p class="fine-print"><em><span>Chris Reid has received funding from a federal Australian Biological Resources Study grant and the NSW Department of Education.</span></em></p>Many gardeners worry these large larvae might damage plants. But before you squish them, read this.Tanya Latty, Associate professor, University of SydneyChris Reid, Adjunct Associate Professor in Zoology, UNSW SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1976712023-01-20T13:37:37Z2023-01-20T13:37:37ZHow do you vaccinate a honeybee? 6 questions answered about a new tool for protecting pollinators<figure><img src="https://images.theconversation.com/files/505433/original/file-20230119-14-78gogp.jpg?ixlib=rb-1.1.0&rect=7%2C0%2C4759%2C3216&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A new vaccine promises better protection against a virulent honeybee infection. </span> <span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/BeeHealth/dec03c6d562c457fa83f50032ab8a6f1/photo">AP Photo/Elise Amendola</a></span></figcaption></figure><p><em>Honeybees, which pollinate <a href="https://www.fda.gov/animal-veterinary/animal-health-literacy/helping-agricultures-helpful-honey-bees">one-third of the crops Americans eat</a>, face many threats, including infectious diseases. On Jan. 4, 2023, a Georgia biotechnology company called <a href="https://www.dalan.com/">Dalan Animal Health</a> announced that it had <a href="https://www.businesswire.com/news/home/20230104005262/en/First-in-Class-Honeybee-Vaccine-Receives-Conditional-License-from-the-USDA-Center-for-Veterinary-Biologics">received a conditional license</a> from the U.S. Department of Agriculture for a vaccine designed to protect honeybees against American foulbrood, a highly destructive infection.</em> </p>
<p><em>To receive a conditional license, which usually lasts for one year and is subject to further evaluation by the USDA, veterinary biological products must be shown to be <a href="https://www.aphis.usda.gov/animal_health/vet_biologics/publications/pel_2_2.pdf">pure, safe and reasonably likely to be effective</a>. Dr. Jennie Durant, an <a href="https://scholar.google.com/citations?user=B1qAtjIAAAAJ&hl=en">agriculture researcher</a> at the University of California, Davis, who specializes in honeybee health, explains why this vaccine is potentially an important step in ongoing efforts to protect pollinators.</em></p>
<h2>1. What threat does this vaccine address?</h2>
<p>The new bee vaccine, <a href="https://www.dalan.com/product">Paenibacillus Larvae Bacterin</a>, aims to protect honeybees from <a href="https://www.ars.usda.gov/northeast-area/beltsville-md-barc/beltsville-agricultural-research-center/bee-research-laboratory/docs/american-foulbrood-disease/">American foulbrood</a>. This highly destructive bacterial disease gets its name from the foul scent honeybee larvae exude when infected. </p>
<p>An outbreak of American foulbrood is effectively a death sentence for a bee colony and can economically devastate a beekeeping operation. The spores from the bacteria, <em>Paenibacillus larvae</em>, are highly transmissible and can remain <a href="https://pollinators.msu.edu/resources/beekeepers/diagnosing-and-treating-american-foulbrood-in-honey-bee-colonies/">virulent for decades</a> after infection. </p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/VENKKufzMAE?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">How American foulbrood affects honeybee colonies.</span></figcaption>
</figure>
<p>Once an outbreak occurs, beekeepers typically have to <a href="https://extension.psu.edu/honey-bee-diseases-american-foulbrood#:%7E:text=American%20foulbrood%20(AFB)%20is%20a,death%20in%20only%20three%20weeks.">destroy any bee colonies</a> that they know were infected to avoid spreading the disease. They also have to destroy the hive boxes the colonies were stored in and any equipment that may have touched infected colonies. </p>
<p>Beekeepers have used antibiotics preventively for decades to keep foulbrood in check and treat infected colonies. Often they mix the antibiotics with powdered sugar and sprinkle it inside the colony box. As often happens when antibiotics are overused, scientists and beekeepers are seeing <a href="https://doi.org/10.1016/j.vetmic.2007.05.018">antibiotic resistance</a> and <a href="https://doi.org/10.1371/journal.pbio.2001861">negative impacts on hive health</a>, such as disruption of the helpful microbes that live in bees’ guts.</p>
<p>In 2017, the U.S. Food and Drug Administration began <a href="https://www.fda.gov/animal-veterinary/development-approval-process/using-medically-important-antimicrobials-bees-questions-and-answers">requiring a veterinarian’s prescription or feed directive</a> to use antibiotics for foulbrood. While this regulatory change <a href="https://www.fda.gov/animal-veterinary/animal-health-literacy/helping-agricultures-helpful-honey-bees">sought to address antibiotic resistance</a>, it limited beekeepers’ access to antibiotics and their ability to treat foulbrood preventively. The vaccine would ideally provide a more sustainable solution. </p>
<h2>2. How effectively does the vaccine prevent infection?</h2>
<p>Studies are still analyzing its effectiveness. One <a href="https://doi.org/10.3389/fvets.2022.946237">published study</a> demonstrated a 30% to 50% increase in resistance to American foulbrood in a vaccinated queen’s offspring. </p>
<p>While this might seem low, it’s important to put the results in context. Given how deadly and contagious American foulbrood is, researchers did not want to directly expose an outdoor hive to foulbrood with an unproven vaccine. Instead, they conducted lab studies where they exposed test hives to around 1,000 times the number of American foulbrood spores a colony would typically be exposed to in the field. Dalan, the manufacturer, has field trials planned for 2023. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1539702810916360192"}"></div></p>
<h2>3. How do you vaccinate honeybees?</h2>
<p>It’s not done with tiny needles – beekeepers mix the vaccine <a href="https://www.dalan.com/science">into bee food</a>. This approach exposes queen bees to inactive <em>Paenibacillus larvae</em> bacteria, which helps larvae hatched in the hive to resist infection. </p>
<p>This is not a <a href="https://www.cdc.gov/coronavirus/2019-ncov/vaccines/different-vaccines/how-they-work.html">mRNA vaccine</a>, like the Pfizer and Moderna COVID vaccines. It’s a more traditional <a href="https://www.news-medical.net/health/What-is-an-Inactivated-Vaccine.aspx">inactive vaccine</a> like the one we use against polio. To understand how the vaccine works, it’s helpful to know what queen bees eat: a protein-rich substance called “<a href="https://www.beeculture.com/royal-jelly-worker-bee-produced-protein-rich-mothers-milk/">royal jelly</a>” that is secreted from glands on the heads of young worker bees. </p>
<p>When queen bees are shipped to a beekeeper, they are typically placed in a small cage with 50 to 200 worker bees that have been fed something called queen candy. This substance is often made with powdered sugar and corn syrup and has the consistency of sugar cookie dough or modeling clay. Worker bees consume the candy, produce royal jelly and feed it to the queen.</p>
<p>The vaccine’s delivery method uses this unique system. A beekeeper can mix the vaccine with the queen candy, which is then digested by worker bees. They produce royal jelly and feed it to the queen, who digests it and then transfers the vaccine to her ovaries. Once she is transferred to the hive and begins laying eggs, the larvae that hatch from those eggs have a heightened immunity to American foulbrood.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/PcDF23HdlUY?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The new vaccine takes advantage of the queen’s central role in the hive.</span></figcaption>
</figure>
<h2>4. Who will use the vaccine?</h2>
<p>According to representatives at Dalan, limited quantities of the vaccine should be available starting in spring 2023 to commercial beekeepers and bee producers, with the aim of supplying smaller-scale beekeepers and hobbyists in the future. </p>
<h2>5. How long will a dose last?</h2>
<p>Dalan is still researching the specifics. Its current understanding is that it will last as long as the queen bee can lay eggs. If she dies, is killed or is replaced, the beekeeper will have to purchase a new vaccinated queen. </p>
<h2>6. Is this a big scientific advance?</h2>
<p>Yes – it is the <a href="https://www.nytimes.com/2023/01/07/science/honeybee-vaccine.html">first vaccine for any insect in the U.S.</a> and could help pave the way for new vaccines to treat other issues that have plagued the beekeeping industry for decades. Honeybees face many urgent threats, including <a href="https://beelab.umn.edu/varroa-mites"><em>Varroa</em> mites</a>, <a href="https://theconversation.com/bees-face-many-challenges-and-climate-change-is-ratcheting-up-the-pressure-190296">climate change</a> and <a href="https://theconversation.com/poor-nutrition-may-be-another-reason-for-the-declining-honey-bee-population-48684">poor nutrition</a>, which makes this vaccine an exciting new development. </p>
<p>Dalan is also working on a vaccine to protect bees against <a href="https://www.ars.usda.gov/northeast-area/beltsville-md-barc/beltsville-agricultural-research-center/bee-research-laboratory/docs/european-foulbrood-disease/">European foulbrood</a>. This disease is less fatal than American foulbrood, but is still highly infectious. Beekeepers have been able to treat it with antibiotics but, as with American foulbrood, they are seeing signs of resistance.</p><img src="https://counter.theconversation.com/content/197671/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jennie L. Durant 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>A vaccine for bees may evoke images of teeny hypodermic needles, but this product works in a sophisticated way that reflects the social structure of honeybee colonies.Jennie L. Durant, Research Affiliate in Human Ecology, University of California, DavisLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1889392022-11-15T13:22:40Z2022-11-15T13:22:40ZAnts – with their wise farming practices and efficient navigation techniques – could inspire solutions for some human problems<figure><img src="https://images.theconversation.com/files/494699/original/file-20221110-21-p2hi2g.jpg?ixlib=rb-1.1.0&rect=10%2C0%2C2235%2C1329&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Leafcutter ants cultivate fungus gardens that feed sprawling colonies.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/three-leafcutter-ants-carrying-leaves-close-up-royalty-free-image/200187319-004">Tim Flach/Stone via Getty Images</a></span></figcaption></figure><p>King Solomon may have gained some of his famed wisdom from an unlikely source – ants.</p>
<p>According to a <a href="https://www.jewishencyclopedia.com/articles/13842-solomon#anchor14">Jewish legend</a>, Solomon conversed with a clever ant queen that confronted his pride, making quite an impression on the Israelite king. In the biblical book of <a href="https://www.biblegateway.com/passage/?search=Proverbs%206%3A6-8&version=KJV">Proverbs (6:6-8)</a>, Solomon shares this advice with his son: “Look to the ant, thou sluggard, consider her ways and be wise. Which having no guide, overseer, or ruler, provideth her meat in the summer, and gathereth her food in the harvest.”</p>
<p>While I can’t claim any familial connection to King Solomon, despite sharing his name, I’ve long admired the wisdom of ants and have spent over 20 years <a href="https://scholar.google.com/citations?user=bnXkcNUAAAAJ&hl=en&oi=sra">studying their ecology, evolution and behaviors</a>. While the notion that ants may offer lessons for humans has certainly been around for a while, there may be new wisdom to gain from what scientists have learned about their biology.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/vG-QZOTc5_Q?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Ants have evolved highly complex social organizations.</span></figcaption>
</figure>
<h2>Lessons from ant agriculture</h2>
<p>As a researcher, I’m especially intrigued by <a href="https://doi.org/10.1093/isd/ixab029">fungus-growing ants</a>, a group of 248 species that cultivate fungi as their main source of food. They include 79 species of <a href="https://wwnorton.com/books/9780393338683">leafcutter ants</a>, which grow their fungal gardens with freshly cut leaves they carry into their enormous underground nests. I’ve excavated hundreds of leafcutter ant nests from Texas to Argentina as part of the scientific effort to understand how these ants coevolved with their fungal crops.</p>
<p>Much like human farmers, each species of fungus-growing ant is very particular about the type of crops they cultivate. Most varieties descend from a type of fungus that the ancestors of fungus-growing ants began growing <a href="https://doi.org/10.1093/isd/ixab029">some 55 million to 65 million years ago</a>. Some of these fungi became domesticated and are now unable to survive on their own without their insect farmers, much like some human crops such as maize.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/-XuPtW8lBCM?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Ants started farming tens of millions of years before humans.</span></figcaption>
</figure>
<p>Ant farmers face many of the same challenges human farmers do, including the threat of pests. A parasite called <a href="https://doi.org/10.1186/s43008-021-00078-8"><em>Escovopsis</em></a> can devastate ant gardens, causing the ants to starve. Likewise in human agriculture, pest outbreaks have contributed to disasters like the <a href="https://evolution.berkeley.edu/the-relevance-of-evolution/agriculture/monoculture-and-the-irish-potato-famine-cases-of-missing-genetic-variation/">Irish Potato Famine</a>, the 1970 <a href="https://doi.org/10.1126/science.171.3976.1113">corn blight</a> and the <a href="https://theconversation.com/with-the-familiar-cavendish-banana-in-danger-can-science-help-it-survive-64206">current threat to bananas</a>.</p>
<p>Since the 1950s, human agriculture has become industrialized and relies on <a href="https://www.birmingham.ac.uk/research/quest/preserving-and-creating-culture/a-global-history-of-monoculture.aspx">monoculture</a>, or growing large amounts of the same variety of crop in a single place. Yet monoculture makes crops more vulnerable to pests because it is easier to destroy an entire field of genetically identical plants than a more diverse one.</p>
<p>Industrial agriculture has looked to chemical pesticides as a partial solution, turning agricultural pest management into a <a href="https://www.alliedmarketresearch.com/pest-control-market">billion-dollar industry</a>. The trouble with this approach is that pests can <a href="https://islandpress.org/books/chasing-red-queen">evolve new ways to get around pesticides</a> faster than researchers can develop more effective chemicals. It’s an arms race – and the pests have the upper hand.</p>
<p>Ants also <a href="https://mitpress.mit.edu/9780262543200/the-convergent-evolution-of-agriculture-in-humans-and-insects/">grow their crops in monoculture</a> and at a similar scale – after all, a leafcutter ant nest can be home to <a href="https://wwnorton.com/books/9780393338683">5 million ants</a>, all of which feed on the fungi in their underground gardens. They, too, use a pesticide to control <em>Escovopsis</em> and other pests. </p>
<p>Yet, their approach to pesticide use differs from humans’ in one important way. Ant pesticides are <a href="https://doi.org/10.1021/acscentsci.0c00978">produced by bacteria</a> they allow to grow in their nests, and in some cases even on their bodies. Keeping bacteria as a living culture allows the microbes to <a href="https://doi.org/10.1128/AEM.00178-21">adapt in real time</a> to evolutionary changes in the pests. In the arms race between pests and farmers, farming ants have discovered that live bacteria can serve as pharmaceutical factories that can keep up with ever-changing pests.</p>
<p>Whereas recent developments in agricultural pest management have focused on <a href="https://entomology.ca.uky.edu/ef130">genetically engineering</a> <a href="https://www.nature.com/scitable/knowledge/library/use-and-impact-of-bt-maize-46975413/">crop plants</a> to produce their own pesticides, the lesson from 55 million years of ant agriculture is to <a href="https://doi.org/10.3389/fsoil.2022.833181">leverage living microorganisms</a> to make <a href="https://doi.org/10.1007/978-981-16-4843-4_13">useful products</a>. Researchers are currently experimenting with <a href="https://link.springer.com/book/10.1007/978-981-10-0707-1">applying live bacteria to crop plants</a> to determine if they are effective at producing pesticides that can evolve in real time along with pests.</p>
<h2>Improving transportation</h2>
<p>Ants can also offer practical lessons in the realm of transportation.</p>
<p>Ants are notoriously good at quickly locating food, whether it’s a dead insect on a forest floor or some crumbs in your kitchen. They do this by leaving a <a href="https://doi.org/10.1111/j.1365-3032.2008.00658.x">trail of pheromones</a> – chemicals with a distinctive smell ants use to guide their nest mates to food. The shortest route to a destination will accumulate the most pheromone because more ants will have traveled back and forth along it in a given amount of time.</p>
<p>In the 1990s, computer scientists developed a <a href="https://www.sciencedirect.com/topics/engineering/ant-colony-optimization">class of algorithms</a> modeled after ant behavior that are very effective at finding the shortest path between two or more locations. Like with real ants, the shortest route to a destination will accumulate the most virtual pheromone because more virtual ants will have traveled along it in a given amount of time. Engineers have used this simple but effective approach to <a href="https://doi.org/10.1016/j.mcm.2010.04.021">design telecommunication networks</a> and <a href="https://doi.org/10.1007%2F978-3-030-50146-4_25">map delivery routes</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/494755/original/file-20221110-3879-61v327.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Leafcutter ants crowding a patch of dirt" src="https://images.theconversation.com/files/494755/original/file-20221110-3879-61v327.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/494755/original/file-20221110-3879-61v327.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/494755/original/file-20221110-3879-61v327.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/494755/original/file-20221110-3879-61v327.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/494755/original/file-20221110-3879-61v327.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/494755/original/file-20221110-3879-61v327.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/494755/original/file-20221110-3879-61v327.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">Thousands of ants can travel along the same path without causing traffic jams.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/close-up-of-plant-growing-on-field-royalty-free-image/764924521">Esteban Castao Solano/EyeEm via Getty Images</a></span>
</figcaption>
</figure>
<p>Not only are ants good at finding the shortest route from their nests to a source of food, thousands of ants are capable of traveling along these routes without causing traffic jams. I recently began collaborating with physicist <a href="https://scholar.google.com/citations?user=reX35vUAAAAJ&hl=es">Oscar Andrey Herrera-Sancho</a> to study how leafcutter ants maintain such a steady flow along their foraging paths without the slowdowns typical of crowded human sidewalks and highways.</p>
<p>We are <a href="http://solomon.rice.edu/2019/01/11/field-research-in-costa-rica/">using cameras to track</a> how each individual ant responds to artificial obstacles placed on their <a href="https://www.alexanderwild.com/Ants/Making-a-Living/The-Farming-Ants-Leafcutters/i-rWjNDhM/A">foraging trails</a>. Our hope is that by getting a better understanding of the rules ants use to respond to both obstacles and the movement of other ants, we can develop algorithms that can eventually help program self-driving cars that never get stuck in traffic.</p>
<h2>Look to the ant</h2>
<p>To be fair, there are plenty of ways ants are far from perfect role models. After all, some ant species are known for <a href="https://www.hup.harvard.edu/catalog.php?isbn=9780674241558">indiscriminate killing</a>, and others for <a href="https://theconversation.com/slave-ants-and-their-masters-are-locked-in-a-deadly-relationship-36737">enslaving babies</a>. </p>
<p>But the fact is that ants <a href="https://www.basicbooks.com/titles/mark-w-moffett/the-human-swarm/9781541617292/">remind us of ourselves</a> – or the way we might like to imagine ourselves – in many ways. They live in complex societies with <a href="https://doi.org/10.1007/s00265-015-2045-3">division of labor</a>. They <a href="https://www.simonandschuster.com/books/Ants-At-Work/Deborah-Gordon/9781451665703">cooperate to raise their young</a>. And they accomplish <a href="https://press.princeton.edu/books/hardcover/9780691179315/ant-architecture">remarkable engineering feats</a> – like building structures with air funnels that can house millions – all without blueprints or a leader. Did I mention their societies are <a href="https://www.press.jhu.edu/books/title/10551/secret-lives-ants">run entirely by females</a>?</p>
<p>There is still a lot to learn about ants. For example, researchers still don’t fully understand <a href="https://doi.org/10.1016/j.tree.2020.11.010">how an ant larva develops</a> into either a queen – a female with wings that can live for 20 years and lay millions of eggs – or a worker – a wingless, often sterile female that lives for less than a year and performs all the other jobs in the colony. What’s more, scientists are constantly discovering new species – <a href="https://www.antwiki.org/wiki/Taxa_Described_in_2021">167 new ant species</a> were described in 2021 alone, bringing the total to more than 15,980. </p>
<p>By considering ants and their many fascinating ways, there’s plenty of wisdom to be gained.</p><img src="https://counter.theconversation.com/content/188939/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Scott Solomon receives funding from the National Science Foundation and the Big Thicket Association. </span></em></p>Over hundreds of million years of evolution, ants have come up with some pretty smart solutions to problems of agriculture, navigation and architecture. People could learn a thing or two.Scott Solomon, Associate Teaching Professor of Ecology and Evolutionary Biology, Rice UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1933022022-10-31T01:15:18Z2022-10-31T01:15:18Z7 ‘creepy crawlies’ you don’t need to be afraid of this spooky season<figure><img src="https://images.theconversation.com/files/492455/original/file-20221031-18-y3ad6b.jpeg?ixlib=rb-1.1.0&rect=20%2C14%2C1911%2C1931&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.inaturalist.org/observations/54516708">vinitapuniasangwan/iNaturalist</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span></figcaption></figure><p>The <a href="https://australian.museum/learn/teachers/learning/bugwise/invertebrate-biodiversity/">vast majority</a> of animals on Earth are invertebrates (animals without backbones) – such as insects, arachnids and crustaceans.</p>
<p>These amazing animals are absolutely <a href="https://www.caledonianconservation.co.uk/cms/resources/Publications/cieemip68jun2010cathrine.pdf">crucial to our ecosystems</a>: they are pollinators, pest controllers, soil creators and waste managers. Invertebrates also serve as food for countless other animals. Despite all their hard work, many of these creatures are often described as “creepy crawlies”.</p>
<p>Their <a href="https://www.sciencealert.com/this-incredible-photo-of-an-ants-face-is-like-something-out-of-a-nightmare">alien-looking</a> bodies might seem like the stuff of nightmares, but the vast majority of invertebrate species are harmless to humans. In fact, the scariest thing about invertebrates is the rate at which they are <a href="https://www.nature.com/articles/s41467-018-07916-1">quietly disappearing</a> from our planet. </p>
<p>Here are seven fascinating creepy crawlies you don’t need to be afraid of.</p>
<h2>Social huntsman spiders (<em>Delena cancerides</em>)</h2>
<p>Native to Australia, social huntsman spiders live in <a href="https://web.archive.org/web/20131103103011/http://domingo.zoology.ubc.ca/avileslab/reprints/InsSoc95.Delena.pdf">large family groups</a> beneath the loose bark of dead or dying trees.</p>
<figure class="align-center ">
<img alt="Brown, large spiders blending into a wooden background" src="https://images.theconversation.com/files/492423/original/file-20221030-38660-ga5tr8.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/492423/original/file-20221030-38660-ga5tr8.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=426&fit=crop&dpr=1 600w, https://images.theconversation.com/files/492423/original/file-20221030-38660-ga5tr8.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=426&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/492423/original/file-20221030-38660-ga5tr8.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=426&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/492423/original/file-20221030-38660-ga5tr8.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=535&fit=crop&dpr=1 754w, https://images.theconversation.com/files/492423/original/file-20221030-38660-ga5tr8.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=535&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/492423/original/file-20221030-38660-ga5tr8.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=535&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A colony of social huntsman spiders found under bark.</span>
<span class="attribution"><a class="source" href="https://www.inaturalist.org/observations/48302773">meggsyroo/iNaturalist</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span>
</figcaption>
</figure>
<p>Sound like nightmare fuel? Don’t worry, social huntsman spiders are gentle giants who rarely bite humans (and cause minimal harm when they do).</p>
<p>Unlike most spider species, social huntsmans live together in groups containing a large adult female and up to 300 of her offspring. Spiders will aggressively defend their nest <a href="https://link.springer.com/article/10.1007/s00040-009-0015-3">against outsiders</a>, suggesting they have ways of recognising nestmates from non-nestmates.</p>
<figure class="align-center ">
<img alt="A large, slightly translucent brown spider standing on a person's palm" src="https://images.theconversation.com/files/492034/original/file-20221027-19202-e6cmuz.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/492034/original/file-20221027-19202-e6cmuz.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/492034/original/file-20221027-19202-e6cmuz.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/492034/original/file-20221027-19202-e6cmuz.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/492034/original/file-20221027-19202-e6cmuz.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/492034/original/file-20221027-19202-e6cmuz.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/492034/original/file-20221027-19202-e6cmuz.jpeg?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 social huntsman spider is large and entirely innocuous.</span>
<span class="attribution"><a class="source" href="https://www.inaturalist.org/observations/37289318">mitchvandyke/iNaturalist</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>At night, individual huntsmans leave the communal nest to hunt their insect prey. Although they are solitary hunters, spiders that come across the same insect will <a href="https://www.jstor.org/stable/41317219">share food</a> rather than fight with one another. In fact, spiderlings would rather <a href="https://zslpublications.onlinelibrary.wiley.com/doi/abs/10.1111/j.1469-7998.2006.00223.x?casa_token=cN2B1dsuWVsAAAAA:k1GM9iOITclvEOxXa8KnaP1dejBiFzx05PkpFroAdwC5oiYgYQy674ZKbrhtiZRVpsfAU5AD_-ZQrzsC">starve to death than</a> cannibalise a fellow spider. By consuming large numbers of bugs, social huntsmans help to keep insect populations under control. </p>
<h2>Giant burrowing cockroach (<em>Macropanesthia rhinoceros</em>)</h2>
<p>Cockroaches are among the world’s most <a href="https://www.bbc.com/future/article/20140918-the-reality-about-roaches">feared and reviled</a> insects – which is a great pity, as most cockroaches are harmless animals that play <a href="https://www.abc.net.au/news/science/2021-04-18/cockroaches-insects-reasons-love-them-environment/100053056">a crucial role in our natural environment</a>. Take the giant burrowing cockroach, found in the warm <a href="https://bie.ala.org.au/species/https://biodiversity.org.au/afd/taxa/f27d18f2-2e8c-4a29-bbaf-15d06c3f2bed">tropical and subtropical forests of Australia</a>.</p>
<figure class="align-center ">
<img alt="A very large dark brown carapaced beetle that spans the entire width of a human hand" src="https://images.theconversation.com/files/492035/original/file-20221027-20183-52ozfn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/492035/original/file-20221027-20183-52ozfn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/492035/original/file-20221027-20183-52ozfn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/492035/original/file-20221027-20183-52ozfn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/492035/original/file-20221027-20183-52ozfn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/492035/original/file-20221027-20183-52ozfn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/492035/original/file-20221027-20183-52ozfn.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">This burrowing cockroach is giant indeed.</span>
<span class="attribution"><a class="source" href="https://www.inaturalist.org/observations/67279797">jessat/iNaturalist</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span>
</figcaption>
</figure>
<p>This gentle giant is the world’s heaviest species of cockroach, <a href="https://blog.csiro.au/insect-of-the-week-cockroach/">tipping the scales at 30-35 grams</a>. Unlike its infamous relatives, the giant burrowing cockroach is not a pest and prefers to spend most of its time in underground burrows. Giant burrowing cockroaches feed on dry eucalyptus leaves, which they collect and drag into their burrows.</p>
<p>By moving and mixing the soil, giant burrowing cockroaches help keep soils healthy. They are excellent mothers who feed and care for their young for <a href="https://academic.oup.com/aesa/article-abstract/84/6/575/96586?redirectedFrom=fulltext">up to nine months</a> after birth. The giant burrowing cockroach is also surprisingly long-lived, with a lifespan of <a href="https://www.bushheritage.org.au/species/giant-cockroaches">up to 10 years</a>.</p>
<h2>Baphomet moth (<em>Creatonotos gangis</em>)</h2>
<p>With weirdly pulsating tentacles, the Baphomet moth looks like an alien nightmare – but these moths are simply looking for love. When male Baphomet moths sense the presence of a female, they inflate enormous, <a href="https://www.australiangeographic.com.au/blogs/creatura-blog/2017/11/the-creatonotos-gangis-is-one-of-australias-strangest-insects/">tentacle-like organs called “coremata”</a>, which produce an irresistible female-attracting chemical bouquet.</p>
<figure class="align-center ">
<img alt="A grey moth with a red body, and four large, hairy tentacles extending from its lower abdomen" src="https://images.theconversation.com/files/492036/original/file-20221027-20344-3hae63.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/492036/original/file-20221027-20344-3hae63.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=627&fit=crop&dpr=1 600w, https://images.theconversation.com/files/492036/original/file-20221027-20344-3hae63.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=627&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/492036/original/file-20221027-20344-3hae63.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=627&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/492036/original/file-20221027-20344-3hae63.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=787&fit=crop&dpr=1 754w, https://images.theconversation.com/files/492036/original/file-20221027-20344-3hae63.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=787&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/492036/original/file-20221027-20344-3hae63.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=787&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The internet has affectionately dubbed this bug ‘tentacle moth’, for obvious reasons.</span>
<span class="attribution"><a class="source" href="https://www.inaturalist.org/observations/54516708">vinitapuniasangwan/iNaturalist</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span>
</figcaption>
</figure>
<p>While it’s not the only moth species with coremata, Baphomet moths take theirs to ridiculous lengths, with “tentacles” sometimes exceeding the length of their abdomens.</p>
<figure class="align-center ">
<img alt="A grey moth with dark stripes on wings sitting on a red dahlia flower" src="https://images.theconversation.com/files/492037/original/file-20221027-18054-68il0b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/492037/original/file-20221027-18054-68il0b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=397&fit=crop&dpr=1 600w, https://images.theconversation.com/files/492037/original/file-20221027-18054-68il0b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=397&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/492037/original/file-20221027-18054-68il0b.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=397&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/492037/original/file-20221027-18054-68il0b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=499&fit=crop&dpr=1 754w, https://images.theconversation.com/files/492037/original/file-20221027-18054-68il0b.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=499&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/492037/original/file-20221027-18054-68il0b.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=499&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The Baphomet moth doesn’t always have creepy tentacles.</span>
<span class="attribution"><span class="source">Bhupinder Bagga/Shutterstock</span></span>
</figcaption>
</figure>
<p>As caterpillars, male Baphomet moths get the ingredients they need to make their female-attracting scents by eating plant leaves that contain chemicals called <a href="https://en.wikipedia.org/wiki/Pyrrolizidine_alkaloid">pyrrolizidine alkaloids</a>. Plants produce these alkaloids to deter plant-munching animals, but Baphomet moths have evolved a way to <a href="https://fzi.uni-freiburg.de/pdf/1985_Boppre_Schneider.pdf">convert these chemicals</a> into their own attractive scents.</p>
<h2>Black soldier fly maggots (<em>Hermetia illucens</em>)</h2>
<p>A big, writhing mass of maggots might not sound like one of nature’s marvels, but the larvae of the black solder fly are recycling superheroes that may one day help <a href="https://www.canberratimes.com.au/story/7868087/tiny-fly-larvaes-big-food-waste-potential/">humanity cut down on food waste</a>. Roiling masses of soldier fly maggots can rapidly devour food through a process physicists colourfully described as a “<a href="https://www.livescience.com/64691-maggot-fountains.html">maggot fountain</a>”.</p>
<figure class="align-center ">
<img alt="A large pile of wriggly maggots of various shades of brown and beige" src="https://images.theconversation.com/files/492422/original/file-20221030-68119-jkbdp7.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/492422/original/file-20221030-68119-jkbdp7.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=449&fit=crop&dpr=1 600w, https://images.theconversation.com/files/492422/original/file-20221030-68119-jkbdp7.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=449&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/492422/original/file-20221030-68119-jkbdp7.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=449&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/492422/original/file-20221030-68119-jkbdp7.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=564&fit=crop&dpr=1 754w, https://images.theconversation.com/files/492422/original/file-20221030-68119-jkbdp7.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=564&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/492422/original/file-20221030-68119-jkbdp7.jpeg?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">
<figcaption>
<span class="caption">The larvae of the black soldier fly are the quintessential ‘maggot’.</span>
<span class="attribution"><a class="source" href="https://www.inaturalist.org/observations/71319102">eduardo4bv/iNaturalist</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>The incredible speed at which maggots demolish food waste has captured the attention of scientists who hope to use soldier fly maggots to convert waste products such as animal faeces and food waste into maggot-based proteins that can be fed to livestock or <a href="https://www.sciencedaily.com/releases/2020/10/201029104951.htm">humans</a>. Yum!</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/jWEM6ohctwU?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<h2>Tailless whip scorpion (Amblypygi)</h2>
<p>Despite their name, tailless whip scorpions are not scorpions, but instead belong to an unusual group of arachnids called <a href="https://blogs.cornell.edu/rayor/amblypygids/">amblypygids</a>. Despite their fearsome appearance, amblypygids lack venom and are timid animals that rarely bite unless threatened.</p>
<figure class="align-center ">
<img alt="A large spider-like creature on a sandy wall with two eggs nearby" src="https://images.theconversation.com/files/492051/original/file-20221027-23859-k1fiu3.jpeg?ixlib=rb-1.1.0&rect=3%2C27%2C2041%2C1250&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/492051/original/file-20221027-23859-k1fiu3.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/492051/original/file-20221027-23859-k1fiu3.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/492051/original/file-20221027-23859-k1fiu3.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/492051/original/file-20221027-23859-k1fiu3.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/492051/original/file-20221027-23859-k1fiu3.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/492051/original/file-20221027-23859-k1fiu3.jpeg?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">Charon grayi, a type of amblypygid, is a shy, retiring creature.</span>
<span class="attribution"><a class="source" href="https://www.inaturalist.org/observations/73918617">teacherharvey/iNaturalist</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span>
</figcaption>
</figure>
<p>These shy animals prefer to stay hidden in humid habitats such as in leaf litter, inside caves or under bark.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1419903965035044866"}"></div></p>
<p>Amblypygids have elongated front legs that act as feelers and help the arachnid locate its insect prey. Once prey is detected, amblypygids use their sharp pedipalps to impale their victim.</p>
<p>Some of these arachnids display <a href="https://www.researchgate.net/profile/Linda-Rayor/publication/293760646_Family_ties/links/60453ee6a6fdcc9c781dc908/Family-ties.pdf">complex social behaviours</a>, with mothers staying near and caring for their young for up to a year. </p>
<h2>The giant elephant mosquito (<em>Toxorhynchites speciosus</em>)</h2>
<p>Few things in life are as horrifying as the high-pitched squeal of a mosquito in the dark. Now imagine an enormous mosquito five times the size of your average mozzie. Measuring in at a shocking <a href="https://www.qm.qld.gov.au/Explore/Find+out+about/Ask+an+Expert/Question+of+the+month/Question+Archive/Questions/2021/January+2021">8mm in length</a>, the Australian elephant mosquito is the world’s largest mosquito species.</p>
<figure class="align-center ">
<img alt="Close-up of a shiny mosquito with feathered antennae" src="https://images.theconversation.com/files/492053/original/file-20221027-25221-lf1bpj.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/492053/original/file-20221027-25221-lf1bpj.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=443&fit=crop&dpr=1 600w, https://images.theconversation.com/files/492053/original/file-20221027-25221-lf1bpj.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=443&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/492053/original/file-20221027-25221-lf1bpj.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=443&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/492053/original/file-20221027-25221-lf1bpj.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=556&fit=crop&dpr=1 754w, https://images.theconversation.com/files/492053/original/file-20221027-25221-lf1bpj.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=556&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/492053/original/file-20221027-25221-lf1bpj.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=556&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Thankfully, the world’s largest mosquito doesn’t lust after human blood.</span>
<span class="attribution"><a class="source" href="https://www.inaturalist.org/observations/18770512">steve_kerr/iNaturalist</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>But fear not, this enormous mozzie is a <a href="https://www.qm.qld.gov.au/Explore/Find+out+about/Ask+an+Expert/Question+of+the+month/Question+Archive/Questions/2021/January+2021">nectar-sipping vegetarian</a>.</p>
<p>Most female mosquitoes need a meal of blood to provide nutrients for their developing eggs. Female elephant mosquitoes collect much-needed nutrients by feeding voraciously on other aquatic insects when they are larvae. And it gets better, because the favourite food of larval elephant mosquitoes is … <a href="https://www.youtube.com/watch?v=tYOMbTizqKA">other mosquito larvae</a>!</p>
<h2>Common scorpion fly (<em>Panorpa</em>)</h2>
<p>Scorpionflies look like a bizarre mashup between a fly and a scorpion. Combine their sinister appearance with a somewhat ghoulish habit of feeding on <a href="https://academic.oup.com/jme/article/52/2/143/887211?login=false">fresh human corpses</a>, and you have the makings of an excellent horror movie.</p>
<p>Luckily, scorpionflies are not, as their name suggests, flying scorpions, nor are they capable of harming a human. In fact, scorpionfly “stingers” are actually enlarged male genitalia!</p>
<figure class="align-center ">
<img alt="A large fly with mottled wings that appears to have a scorpion's tail" src="https://images.theconversation.com/files/492055/original/file-20221027-19729-pkqydq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/492055/original/file-20221027-19729-pkqydq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/492055/original/file-20221027-19729-pkqydq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/492055/original/file-20221027-19729-pkqydq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/492055/original/file-20221027-19729-pkqydq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/492055/original/file-20221027-19729-pkqydq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/492055/original/file-20221027-19729-pkqydq.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 male scorpionfly has claspers at the end of its tail that look like a scorpion’s tail.</span>
<span class="attribution"><span class="source">CHEN HSI FU/Shutterstock</span></span>
</figcaption>
</figure>
<p>During courtship, male scorpionflies attempt to woo females by offering them either a dead insect or <a href="https://onlinelibrary-wiley-com.ezproxy.library.sydney.edu.au/doi/full/10.1111/j.1463-6395.2010.00474.x?casa_token=_6NoEI7Is3YAAAAA%3AOCP0g5_qtAauQBgfTo0wxxhMAwiTczPXIDoghrG73mbL1PuHHZkzpIUk8uIFpwaXsUjpA1XRp4J2AdtC">a blob of saliva</a>. Scorpion flies are mostly scavengers and are frequently seen stealing prey from spider webs.</p>
<p>They are among the first insects to turn up on newly deceased corpses, making them important for <a href="https://academic.oup.com/jme/article/52/2/143/887211?login=false">establishing time of death</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/when-remains-are-found-in-a-suitcase-forensics-can-learn-a-lot-from-the-insects-trapped-within-189315">When remains are found in a suitcase, forensics can learn a lot from the insects trapped within</a>
</strong>
</em>
</p>
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<img src="https://counter.theconversation.com/content/193302/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tanya Latty receives funding from The Australian Research Council. She is affiliated with Invertebrates Australia (conservation organisation), the Australasian Society for the Study of Animal Behaviour and the Australian Entomological Society </span></em></p>Invertebrates are the most abundant animals on our planet – and the vast majority are nothing to be afraid of, despite their appearances.Tanya Latty, Associate professor, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1918472022-10-06T01:28:04Z2022-10-06T01:28:04ZA large cockroach thought extinct since the 1930s was just rediscovered on a small island in Australia<figure><img src="https://images.theconversation.com/files/488383/original/file-20221005-18-20lau3.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3532%2C2360&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Justin Gilligan/DPE</span>, <span class="license">Author provided</span></span></figcaption></figure><p>In 1887, Australian Museum scientists <a href="https://australian.museum/blog/museullaneous/a-natural-history-classic-robert-etheridge-jnr/">undertook a pioneering expedition</a> to Lord Howe Island, a tiny patch of land off the east coast of Australia. Among their many discoveries, they recorded “a large <em>Blatta</em>” – a type of <a href="https://australian.museum/learn/animals/insects/cockroaches-order-blattodea/">cockroach</a> – under a decaying log.</p>
<p>This was later described as <em><a href="https://bie.ala.org.au/species/https://biodiversity.org.au/afd/taxa/7714ade9-2a0f-439e-a76e-4769776211e9">Panesthia lata</a></em>, the Lord Howe Island wood-feeding cockroach. <em>P. lata</em> was noted as being highly abundant, playing a key role in nutrient recycling, and presumably a food source for the many birds on the island.</p>
<p>Alas, in 1918 <a href="https://www.abc.net.au/news/2021-02-02/lord-howe-island-recovers-from-rat-infestation/13111770">rats arrived on the island</a> from a shipwreck. By the late 20th century, <em>P. lata</em> could not be found despite extensive searches over multiple decades, and was assumed to have gone extinct due to rat predation.</p>
<p>But could it have survived in some unexplored pocket of the island?</p>
<figure class="align-center ">
<img alt="A dark blue ocean with a rocky, curved island in the middle of the photo" src="https://images.theconversation.com/files/488382/original/file-20221005-16-4c41xm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/488382/original/file-20221005-16-4c41xm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=419&fit=crop&dpr=1 600w, https://images.theconversation.com/files/488382/original/file-20221005-16-4c41xm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=419&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/488382/original/file-20221005-16-4c41xm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=419&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/488382/original/file-20221005-16-4c41xm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=527&fit=crop&dpr=1 754w, https://images.theconversation.com/files/488382/original/file-20221005-16-4c41xm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=527&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/488382/original/file-20221005-16-4c41xm.jpg?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">The crescent-shaped Lord Howe Island off the eastern coast of Australia is home to unique flora and fauna.</span>
<span class="attribution"><span class="source">John Carnemolla/Shutterstock</span></span>
</figcaption>
</figure>
<h2>Putting the cockroach back where it belongs</h2>
<p>In 2019, the New South Wales Department of Planning and Environment (NSW DPE) implemented the final stage of its highly successful (although at times controversial) <a href="https://www.lhib.nsw.gov.au/environment/environmental-programs/rodent-eradication">rat eradication program</a> on the island.</p>
<p>Following this, I and my colleagues from NSW DPE, Lord Howe Island Museum, Chau Chak Wing Museum, CSIRO’s Australian National Insect Collection and the University of Melbourne became interested in the biology of <em>P. lata</em> and the potential to repopulate the island with this insect.</p>
<p>This was on the cards because in 2001, <em>P. lata</em> had been discovered on Blackburn and Roach islands, two small islands near Lord Howe Island.</p>
<figure class="align-center ">
<img alt="A very large brown bug on a person's hand" src="https://images.theconversation.com/files/488384/original/file-20221005-22-3b3220.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/488384/original/file-20221005-22-3b3220.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/488384/original/file-20221005-22-3b3220.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/488384/original/file-20221005-22-3b3220.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/488384/original/file-20221005-22-3b3220.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/488384/original/file-20221005-22-3b3220.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/488384/original/file-20221005-22-3b3220.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 wood-feeding cockroach doesn’t go anywhere near people’s homes.</span>
<span class="attribution"><span class="source">Justin Gilligan/DPE</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>But hang on a minute: why would we want to put cockroaches, one of the most reviled creatures on Earth, back on a beautiful island after their seemingly fortuitous extermination?</p>
<p>Well, <em>P. lata</em> is, believe it not, quite cute and charismatic, and has no interest in going into people’s houses. It is wingless, about 4cm long, and stays hidden in the forest, where it burrows into the soil and feeds on leaf litter and rotting wood by night.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-we-wiped-out-the-invasive-african-big-headed-ant-from-lord-howe-island-106447">How we wiped out the invasive African big-headed ant from Lord Howe Island</a>
</strong>
</em>
</p>
<hr>
<h2>Fortuitous rocks</h2>
<p>In July we received funding from the Australia Pacific Science Foundation to investigate the genetics and ecology of <em>P. lata</em> from Blackburn and Roach Islands. So Maxim Adams, an honours student in our lab at the University of Sydney, and Nicholas Carlile from NSW DPE headed off to Lord Howe Island to begin the study.</p>
<figure class="align-center ">
<img alt="Close-up of a large brown bug showing its spiky legs" src="https://images.theconversation.com/files/488385/original/file-20221005-17-vhv6ij.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/488385/original/file-20221005-17-vhv6ij.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/488385/original/file-20221005-17-vhv6ij.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/488385/original/file-20221005-17-vhv6ij.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/488385/original/file-20221005-17-vhv6ij.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/488385/original/file-20221005-17-vhv6ij.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/488385/original/file-20221005-17-vhv6ij.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 wood-feeding cockroach was thought to be extinct for decades, after extensive searches turned up no populations on Lord Howe Island.</span>
<span class="attribution"><span class="source">Justin Gilligan/DPE</span></span>
</figcaption>
</figure>
<p>Bad weather prevented them from going out to Blackburn Island, so they decided to examine potential sites on Lord Howe Island that might have once been teeming with <em>P. lata</em> before the rats arrived.</p>
<p>They walked to a secluded area in the north of the island, and decided to turn over a few rocks. Literally the first rock they checked revealed a small congregation of the cockroaches! I was due to join them three days later, but they called me that afternoon with great excitement to relay the news.</p>
<figure class="align-center ">
<img alt="Two men crouching under an old tree examining rocks" src="https://images.theconversation.com/files/488386/original/file-20221005-12-54l5u6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/488386/original/file-20221005-12-54l5u6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/488386/original/file-20221005-12-54l5u6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/488386/original/file-20221005-12-54l5u6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/488386/original/file-20221005-12-54l5u6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/488386/original/file-20221005-12-54l5u6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/488386/original/file-20221005-12-54l5u6.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">Maxim Adams and Nicholas Carlile under the banyan tree where they made the surprise discovery.</span>
<span class="attribution"><span class="source">Justin Gilligan/DPE</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>They found a few others within a few metres under the same fig tree, but extensive searching over the next few days revealed none in other nearby areas or other parts of the island. </p>
<h2>Not the same as their neighbours</h2>
<p>We carried out some preliminary DNA tests upon our return to Sydney, finding the rediscovered Lord Howe Island population of cockroaches was distinct from the ones found on Blackburn and Roach islands.</p>
<p>It is possible the population hung on as a result of rodent baiting in the area. The baiting was done in recent decades to assist the survival of various other threatened species.</p>
<p>We are now carrying out more extensive DNA studies, including historical museum samples collected from the late 19th and early 20th centuries, and samples from Ball’s Pyramid, roughly 20km southeast of Lord Howe Island, collected by Dick Smith in the 1960s.</p>
<figure class="align-center ">
<img alt="A jagged shard of rock stretching up from the surface of the ocean" src="https://images.theconversation.com/files/488387/original/file-20221005-24-3b3220.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/488387/original/file-20221005-24-3b3220.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/488387/original/file-20221005-24-3b3220.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/488387/original/file-20221005-24-3b3220.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/488387/original/file-20221005-24-3b3220.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/488387/original/file-20221005-24-3b3220.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/488387/original/file-20221005-24-3b3220.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">Ball’s Pyramid is the eroded remnant of an ancient shield volcano, and part of Lord Howe Island Marine Park.</span>
<span class="attribution"><span class="source">Ashley Whitworth/Shutterstock</span></span>
</figcaption>
</figure>
<p>Through these studies, we hope to determine the relationship of the rediscovered population with those originally collected on the island a century or more ago and those on the outer islands. We also hope to uncover the origins and evolutionary history of <em>P. lata</em>.</p>
<p>The Lord Howe Island Group is a <a href="https://whc.unesco.org/en/list/186/">UNESCO world heritage site</a> of global natural significance, and is home to more than 100 plant species found nowhere else on Earth, and many more endemic animal species. The biology of many of these species, particularly the island’s invertebrates, remains mysterious.</p>
<p>We hope our use of DNA techniques will help us to establish <em>P. lata</em> as a model for understanding several million years of evolution on the Lord Howe Island archipelago, and aid the re-establishment of this shy yet charismatic creature on its homeland.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-we-traced-the-underwater-volcanic-ancestry-of-lord-howe-island-110503">How we traced the underwater volcanic ancestry of Lord Howe Island</a>
</strong>
</em>
</p>
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<img src="https://counter.theconversation.com/content/191847/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Nathan Lo receives funding from The Australia and Pacific Science Foundation.</span></em></p>A small congregation of the cockroaches was under the first rock scientists looked under, by sheer accident.Nathan Lo, Associate Professor, School of Biological Sciences, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1828552022-09-19T05:53:39Z2022-09-19T05:53:39ZWhat constitutes a mind? Lars Chittka challenges our perception of sentience with the smallest of creatures<figure><img src="https://images.theconversation.com/files/479811/original/file-20220818-22-n03lif.jpg?ixlib=rb-1.1.0&rect=6%2C0%2C1017%2C766&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Jon Sullivan/Wikimedia Commons</span></span></figcaption></figure><p>At the beginning of my research career around 15 years ago, any suggestion that a bee, or any invertebrate, had a mind of its own or that it could experience the world in an intricate and multifaceted way would be met with ridicule. As Lars Chittka points out in the opening chapters of <a href="https://press.princeton.edu/books/hardcover/9780691180472/the-mind-of-a-bee">The Mind of a Bee</a>, the attribution of human emotions and experiences was seen as naivety and ignorance; anthropomorphism was a dirty word. </p>
<p>Pet owners eagerly ascribe emotions to their animals, but the simple brain of a bee surely could not experience the rich tapestry that is our existence. They are far too simplistic and robotic, right?</p>
<hr>
<p><em>Review: The Mind of a Bee – Lars Chittka (Princeton University Press).</em></p>
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<a href="https://images.theconversation.com/files/479813/original/file-20220818-1579-ok5ass.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/479813/original/file-20220818-1579-ok5ass.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/479813/original/file-20220818-1579-ok5ass.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=906&fit=crop&dpr=1 600w, https://images.theconversation.com/files/479813/original/file-20220818-1579-ok5ass.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=906&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/479813/original/file-20220818-1579-ok5ass.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=906&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/479813/original/file-20220818-1579-ok5ass.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1138&fit=crop&dpr=1 754w, https://images.theconversation.com/files/479813/original/file-20220818-1579-ok5ass.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1138&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/479813/original/file-20220818-1579-ok5ass.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1138&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<p>Lars Chittka has been researching honeybees for the past 30 years. The Mind of a Bee is a collection of his research stories. It also covers the influential figures in bee research and provides a historical perspective on the research that much behavioural work is built on today. </p>
<p>People have long been curious about the behaviour of bees. Many questions posed in the 1800s are still around. While Chittka’s beautifully collated and captivating “story” does not present research results that are necessarily new, to read them presented together like this, I find myself tantalised by questions I had not thought to ponder. For example, how do bees decide who stays and who leaves when a swarm is formed? </p>
<h2>The world of a bee</h2>
<p>The book opens by challenging you to put yourself into the <em>world</em> of a bee. </p>
<p>A honeybee’s experience of the world is so completely foreign to our own that to understand and research it is a challenge not to be underestimated. Indeed, it is understandable that we have relegated the experience of bees to something simplistic and robotic when you discover the difficulties faced by researchers. </p>
<p>First, picture yourself as a bee. You have wings, allowing flight. Your vision is not as sharp anymore, worse than your grandfather’s with his coke-bottle glasses, but you see things more quickly. Life is experienced on a faster time line – what was once a movie is now more like a series of images in a slideshow. </p>
<p>The antennae protruding from your head function as hands, ears, tongues and noses, all in one. You can tell if someone has visited a flower before you – a flower you picked out of a field of hundreds by its scent, and which you found by following the directions you felt a fellow bee dance for you inside the pitch-black hive perhaps ten kilometres from your current position. </p>
<p>Chittka then invites us to imagine the <em>life</em> of the bee. Upon exiting the hive for the first time, you must learn its location through a series of flights – behaviour observed in other central-place foragers such as ants and wasps. Failure to recognise your hive and return home equals death. </p>
<p>Once you have memorised the location of your hive, you then must successfully navigate your way to and from various resource-rich patches as efficiently as possible, learning new locations, the timing of certain flowers releasing their nectar, and the techniques required to manipulate other flowers into relinquishing theirs. </p>
<p>So far, this sounds instinctual, a basic response to hunger. Yet Chittka presents additional research – historical and current – that provides insights into the cognitive skills of bees. We learn that bees can count. They can learn rules and categorise flowers. And they can learn from others, not only which flowers are rewarding, but how to access them. </p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/exsrX6qsKkA?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
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<p>One of my favourite experiments, perhaps for the videos that accompanied the publication, is of bumblebees pushing balls into holes to get rewards. This skill can be learnt by an observer bee and, what is truly fascinating, it can be improved upon. The observer bee can solve the task by copying the goal rather than strictly copying the technique, demonstrating an understanding of the task and the desired outcome. </p>
<p>But when would a bee ever need to push a ball into a hole to be rewarded with some “nectar”? </p>
<p>As Chittka rightly points out, the questions we pose to understand the minds of bees must have a biological relevance to make sense. That is, we need to understand what is important to the survival of bees, what is essential in their existence, and frame our questions of intelligence and sentience around that aspect. If we ask the wrong questions, we will never fully understand the answers – like asking a fish to climb a tree and finding it lacking.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/480260/original/file-20220822-18038-tcb5ik.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/480260/original/file-20220822-18038-tcb5ik.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/480260/original/file-20220822-18038-tcb5ik.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=802&fit=crop&dpr=1 600w, https://images.theconversation.com/files/480260/original/file-20220822-18038-tcb5ik.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=802&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/480260/original/file-20220822-18038-tcb5ik.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=802&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/480260/original/file-20220822-18038-tcb5ik.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1007&fit=crop&dpr=1 754w, https://images.theconversation.com/files/480260/original/file-20220822-18038-tcb5ik.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1007&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/480260/original/file-20220822-18038-tcb5ik.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1007&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">Lars Chittka.</span>
<span class="attribution"><span class="source">Wikimedia commons</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h2>Consciousness and emotion</h2>
<p>The punch this book packs is in the subtle build-up to the final chapters, whereupon it becomes increasingly hard to deny the “mind” of a bee. </p>
<p>While it is impossible to prove consciousness in another organism, the research Chittka has collated provides a compelling argument. In The Mind of a Bee, you will read that bees feel emotions and pain, display metacognition (that is, they know what they know), and show individual differences in their ability to learn, with fast and slow learners. Bees are aware of their bodies and the outcomes of their actions, and they display intentionality through tool use – previously only recognised in humans, primates, and the <a href="https://en.wikipedia.org/wiki/Corvidae">corvidae</a> family of birds. </p>
<p>Regardless of whether you believe a bee has a mind or not, globally there has been a <a href="https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/2041-210X.13208">change in research practices as invertebrates are seen to experience the world more fully</a>. </p>
<p>Ethics approval is required for work on some invertebrates, including crustaceans and cephalopods, and statements of ethical treatment of other invertebrates are required for submission of manuscripts to some journals. To suggest an invertebrate, such as a bee, may have these fuller experiences of life is no longer attracting ridicule, but instead is creating an uncomfortable space for insect researchers, who may not wish to confront the reality of their experiments.</p>
<p>We have underestimated the intelligence of bees and other “lower” species for far too long; it is time to pay attention. Chittka shows us that bees have the key ingredients of a mind: they have a representation of space, they can learn by observation, and they display simple tool use. Bees have demonstrated a flexible memory, with ideas of what they want to achieve, an ability to explore suitable solutions to get it, and an awareness of the possible outcomes of their own actions. </p>
<p>Experiments have further shown that bees appear to attach emotional states to rewards and punishments. While their biology and experience of the world is very different to ours, it is reasonable to believe that they do indeed possess a mind capable of experiencing the rich tapestry of life we have so long thought only available to us.</p>
<p>Written with moments of levity and soaked in curiosity, The Mind of a Bee is a delight. While some may not be ready to ascribe sentience to something as “simple” as a bee, this book will prompt you to question why not. As Chittka so eloquently put it in a recent talk: “We are thinking, suffering, enjoying beings in a world of other thinking, suffering and enjoying beings, with different minds and perceptions.” </p>
<p>I for one am looking at the world a little differently with that in mind.</p><img src="https://counter.theconversation.com/content/182855/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Eliza Middleton receives funding from the Australian Research Council</span></em></p>Recent studies suggest that the mind of a bee is far more sophisticated than once believed.Eliza Middleton, Laboratory Manager, School of Life and Environmental Sciences, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1885592022-09-12T12:12:36Z2022-09-12T12:12:36ZHow do ants crawl on walls? A biologist explains their sticky, spiky, gravity-defying grip<figure><img src="https://images.theconversation.com/files/478784/original/file-20220811-23-w41scx.jpg?ixlib=rb-1.1.0&rect=0%2C6%2C2272%2C1693&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Walking vertically – or even upside down – is a piece of cake for ants.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/climbing-up-a-wall-royalty-free-image/175996454">pecchio/iStock via Getty Images Plus</a></span></figcaption></figure><figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=293&fit=crop&dpr=1 600w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=293&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=293&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=368&fit=crop&dpr=1 754w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=368&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=368&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><em><a href="https://theconversation.com/us/topics/curious-kids-us-74795">Curious Kids</a> is a series for children of all ages. If you have a question you’d like an expert to answer, send it to <a href="mailto:curiouskidsus@theconversation.com">curiouskidsus@theconversation.com</a>.</em></p>
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<blockquote>
<p><strong>How do ants crawl on walls? – Ethan, age 9, Dallas, Texas</strong></p>
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<hr>
<p>When I first started my job <a href="https://scholar.google.com/citations?user=hrO-baMAAAAJ&hl=en&oi=ao">as a biologist</a> at the University of South Florida, I drove my Jeep to a grassy field, dug up a mound of fire ants and shoveled it into a 5-gallon bucket. Immediately, thousands of ants swarmed out of the soil and up the walls of the bucket headed for freedom. Luckily I had a lid.</p>
<p>How do ants make climbing walls, ceilings and other surfaces look so easy? <a href="https://scholar.google.com/citations?hl=en&view_op=list_works&gmla=AJsN-F7sTTsnLhAu39Zwg-90iH0Hwx9849J-UEbRISOmCR2ouYfcOp2_o8P0yqau7y64vL6XeYU3LFJ-RpqacVDz2Q8Qln7xBQ&user=hrO-baMAAAAJ">I’ve been studying ants for 30 years</a>, and their climbing abilities never cease to amaze me. </p>
<p>Worker ants – <a href="https://theconversation.com/six-amazing-facts-you-need-to-know-about-ants-100478">who are all female</a> – have an impressive <a href="https://doi.org/10.1007/s00114-006-0194-y">toolbox of claws, spines, hairs</a> and sticky pads on their feet that enable them to scale almost any surface.</p>
<h2>Human hands vs. ant feet</h2>
<p>To understand ant feet, it helps to compare them with human hands. Your hand has one broad segment, the palm. Sprouting from your palm are four fingers and an opposable thumb. Each finger has three segments, while your thumb has only two segments. A hard nail grows from the tips of your fingers and thumb.</p>
<p>Humans have two hands – ants have six feet. Ant feet are similar to your hands but are more complex, with an additional set of weird-looking parts that enhance them. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/479207/original/file-20220815-14662-uvsojl.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A microscopic view of an ant's foot, with segments numbered. Labeled are claw, thick spine, thin spine and hairs." src="https://images.theconversation.com/files/479207/original/file-20220815-14662-uvsojl.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/479207/original/file-20220815-14662-uvsojl.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/479207/original/file-20220815-14662-uvsojl.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/479207/original/file-20220815-14662-uvsojl.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/479207/original/file-20220815-14662-uvsojl.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/479207/original/file-20220815-14662-uvsojl.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/479207/original/file-20220815-14662-uvsojl.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>
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<span class="caption">A closeup view of one multisegmented ant foot. Each foot is lined with spiky tools that help grip almost any surface.</span>
<span class="attribution"><span class="source">Deby Cassill</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
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<p>Ant feet have five jointed segments, with the end segment sporting a pair of claws. The claws are shaped like a cat’s and can grip irregularities on walls. Each foot segment also has thick and thin spines and hairs that provide additional traction by sticking into microscopic pits on textured surfaces like bark. Claws and spines have the added benefit of protecting ant feet from hot pavement and sharp objects, just as your feet are protected by shoes. </p>
<p>But the feature that truly separates human hands from ant feet are inflatable sticky pads, called arolia.</p>
<h2>Sticky feet</h2>
<p><a href="https://pubs.rsc.org/en/content/articlehtml/2011/sm/c1sm06269g">Arolia are located between the claws at the tip of every ant foot</a>. These balloonlike pads allow ants to defy gravity and crawl on ceilings or ultrahard surfaces like glass.</p>
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<a href="https://images.theconversation.com/files/478782/original/file-20220811-27-lrnm6e.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A microscopic view of a fire ant's foot. The end shows two retracted claws revealing an inflated pillow like structure." src="https://images.theconversation.com/files/478782/original/file-20220811-27-lrnm6e.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/478782/original/file-20220811-27-lrnm6e.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/478782/original/file-20220811-27-lrnm6e.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/478782/original/file-20220811-27-lrnm6e.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/478782/original/file-20220811-27-lrnm6e.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/478782/original/file-20220811-27-lrnm6e.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/478782/original/file-20220811-27-lrnm6e.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">Inflatable sticky pads bring the cling.</span>
<span class="attribution"><span class="source">Deby Cassill</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>When an ant walks up a wall or across a ceiling, gravity causes its claws to swing wide and pull back. At the same time, its leg muscles pump fluids into the pads at the end of its feet, causing them to inflate. This <a href="https://bugunderglass.com/do-insects-have-blood/">body fluid is called hemolymph</a>, which is a sticky fluid similar to your blood that circulates throughout an ant’s body. </p>
<p>After the hemolymph pumps up the pad, some of it leaks outside the pad, which is how ants can stick to a wall or a ceiling. But when an ant picks up its foot, its leg muscles contract and suck most of the fluid back into the pad and then back up the leg. This way an ant’s blood is reused over and over – pumped from the leg into the pad, then sucked back up the leg – so none is left behind. </p>
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<img src="https://cdn.theconversation.com/static_files/files/2250/ezgif.com-gif-maker.gif?1660317974">
<figcaption><span class="Ant feet in action on glass. Courtesy of Deby Cassill.">Ant feet in action on glass. Courtesy of Deby Cassill.</span></figcaption>
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<p>Ants are feather-light, so six sticky pads are enough to hold them against the pull of gravity on any surface. In fact, at home in their underground chambers, <a href="https://doi.org/10.1007/s00114-006-0194-y">ants use their sticky pads to sleep on the ceiling</a>. By sleeping on the ceiling, ants avoid the rush-hour traffic of other ants on the chamber floors.</p>
<h2>A unique gait</h2>
<p>When you walk, your left and right feet alternate so one is on the ground while the other is in the air, moving forward. Ants also alternate their feet, with three on the surface and three in the air at a time. </p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/lduoLbm0_IU?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">A computer simulation showing an ant’s special walk. Created by Shihui Guo.</span></figcaption>
</figure>
<p>The walking pattern of ants is <a href="https://doi.org/10.1242/jeb.156.1.215">unique among six-legged insects</a>. In ants, the front and back left feet are on the ground with the middle right foot, while the front and back right feet and the middle left foot are in the air. Then they switch. It’s fun to try to copy this triangular pattern using three fingers on each hand. </p>
<p>The next time you see an ant crawling up a wall, look closely and you might witness some of these fascinating features at work.</p>
<hr>
<p><em>Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to <a href="mailto:curiouskidsus@theconversation.com">CuriousKidsUS@theconversation.com</a>. Please tell us your name, age and the city where you live.</em></p>
<p><em>And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.</em></p><img src="https://counter.theconversation.com/content/188559/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Deby Cassill 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>Ant feet are equipped with an array of tools – from retractable sticky pads to claws to special spines and hairs – enabling them to defy gravity and grip virtually any surface.Deby Cassill, Associate Professor of Integrative Biology, University of South FloridaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1840302022-07-29T12:21:41Z2022-07-29T12:21:41ZCharles Henry Turner: The little-known Black high school science teacher who revolutionized the study of insect behavior in the early 20th century<figure><img src="https://images.theconversation.com/files/475880/original/file-20220725-12-r36mpc.png?ixlib=rb-1.1.0&rect=1%2C1%2C1010%2C573&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Turner was the first scientist to prove certain insects could remember, learn and feel.</span> <span class="attribution"><span class="source">Courtesy of Charles I. Abramson</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>On a crisp autumn morning in 1908, an elegantly dressed African American man strode back and forth among the pin oaks, magnolias and silver maples of <a href="https://www.stlouis-mo.gov/parks/parks/browse-parks/view-park.cfm?parkID=68&parkName=O%27Fallon%20Park">O’Fallon Park in St. Louis, Missouri</a>. After placing a dozen dishes filled with strawberry jam atop several picnic tables, biologist Charles Henry Turner retreated to a nearby bench, notebook and pencil at the ready. </p>
<p>Following a midmorning break for tea and toast (topped with strawberry jam, of course), Turner returned to his outdoor experiment. At noon and again at dusk, he placed jam-filled dishes on the park tables. As he discovered, <a href="https://entnemdept.ufl.edu/creatures/misc/BEES/euro_honey_bee.htm">honeybees (<em>Apis mellifera</em>)</a> were reliable breakfast, lunch and dinner visitors to the sugary buffet. After a few days, Turner stopped offering jam at midday and sunset, and presented the treats only at dawn. Initially, the bees continued appearing at all three times. Soon, however, <a href="https://mellenpress.com/author/charles-i-abramson/4825/">they changed their arrival patterns</a>, visiting the picnic tables only in the mornings.</p>
<p>This <a href="https://psychology.okstate.edu/museum/turner/turnerbio.html">simple but elegantly devised experiment</a> led Turner to conclude that bees can perceive time and will rapidly develop new feeding habits in response to changing conditions. These results were among the first in a cascade of groundbreaking discoveries that Turner made about insect behavior.</p>
<p>Across his distinguished 33-year career, <a href="https://doi.org/10.1016/j.cub.2020.08.075">Turner authored 71 papers</a> and was the first African American to have his research <a href="https://doi.org/10.1126/science.ns-19.466.16">published in the prestigious journal Science</a>. Although his name is barely known today, <a href="https://psychology.okstate.edu/museum/turner/turnermain.html">Charles Henry Turner was a pioneer in studying bees</a> and should be considered among the great entomologists of the 19th and 20th centuries. While researching <a href="https://www.penguinrandomhouse.com/books/557206/the-butterfly-effect-by-edward-d-melillo/">my book on human interactions with insects in world history</a>, I became aware of Turner’s pioneering work on insect cognition, which constituted much of his groundbreaking research on animal behavior.</p>
<h2>Humble beginnings</h2>
<p>Turner was born in Cincinnati in 1867, a mere two years after the Civil War ended. The son of a church custodian and a nurse who was formerly enslaved, he grew up under the specter of Jim Crow – a set of formal laws and informal practices that relegated <a href="https://www.history.com/topics/early-20th-century-us/jim-crow-laws">African Americans to second-class status</a>.</p>
<p>The social environment of Turner’s childhood included school and housing segregation, frequent lynchings and the denial of basic democratic rights to the city’s nonwhite population. Despite immense obstacles to his educational goals and professional aspirations, Turner’s tenacious spirit carried him through.</p>
<p>As a young boy, he developed an abiding fascination with small creatures, capturing and cataloging thousands of ants, beetles and butterflies. An aptitude for science was just one of Turner’s many talents. At Gaines High School, he led his all-Black class, securing his place as valedictorian.</p>
<p>Turner went on to earn a Bachelor of Science degree from the University of Cincinnati, and he became the first African American to receive a <a href="https://www.britannica.com/biography/Charles-Henry-Turner">doctorate in zoology from the University of Chicago</a>. Turner’s cutting-edge doctoral dissertation, “<a href="https://doi.org/10.1002/cne.920170502">The Homing of Ants: An Experimental Study of Ant Behavior</a>,” was later excerpted in the September 1907 issue of the Journal of Comparative Neurology and Psychology.</p>
<p>Despite his brilliance, Turner was unable to secure long-term employment in higher education. The <a href="https://doi.org/10.1007/s13592-021-00855-9">University of Chicago refused to offer him a job</a>, and Booker T. Washington was too cash-strapped to hire him at the <a href="https://www.tuskegee.edu/about-us/history-and-mission">all-Black Tuskegee Normal and Industrial Institute in Alabama</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/474367/original/file-20220715-16-uu04fh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Black and white photo of a large brick high school building." src="https://images.theconversation.com/files/474367/original/file-20220715-16-uu04fh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/474367/original/file-20220715-16-uu04fh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=299&fit=crop&dpr=1 600w, https://images.theconversation.com/files/474367/original/file-20220715-16-uu04fh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=299&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/474367/original/file-20220715-16-uu04fh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=299&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/474367/original/file-20220715-16-uu04fh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=376&fit=crop&dpr=1 754w, https://images.theconversation.com/files/474367/original/file-20220715-16-uu04fh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=376&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/474367/original/file-20220715-16-uu04fh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=376&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Sumner High School in St. Louis, Mo., circa 1908.</span>
<span class="attribution"><a class="source" href="https://mohistory.org/collections/item/N46489">Missouri Historical Society</a></span>
</figcaption>
</figure>
<p>Following a brief stint at the University of Cincinnati and a temporary position at Clark College (now Clark Atlanta University), Turner spent the remainder of his career teaching at <a href="https://www.slps.org/domain/8207">Sumner High School in St. Louis</a>. As of 1908, his salary was a meager US$1,080 a year – <a href="https://www.in2013dollars.com/us/inflation/1908">around $34,300 in today’s dollars</a>. At Sumner – without access to a fully equipped laboratory, a research library or graduate students – Turner made trailblazing discoveries about insect behavior. </p>
<h2>Probing the minds of insects</h2>
<p>Among Turner’s most significant findings was that wasps, bees, sawflies and ants – members of the <em>Hymenoptera</em> order – are <a href="https://psychology.okstate.edu/museum/turner/turnerbio.html">not simply primitive automatons</a>, as so many of his contemporaries thought. Instead, they are organisms with the capacities to remember, learn and feel. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/474365/original/file-20220715-22-fzxqs6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Black and white engraving of a variety of bees from 1894." src="https://images.theconversation.com/files/474365/original/file-20220715-22-fzxqs6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/474365/original/file-20220715-22-fzxqs6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=394&fit=crop&dpr=1 600w, https://images.theconversation.com/files/474365/original/file-20220715-22-fzxqs6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=394&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/474365/original/file-20220715-22-fzxqs6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=394&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/474365/original/file-20220715-22-fzxqs6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=495&fit=crop&dpr=1 754w, https://images.theconversation.com/files/474365/original/file-20220715-22-fzxqs6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=495&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/474365/original/file-20220715-22-fzxqs6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=495&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Bees were not well understood at the turn of the 20th century. Illustration published by Popular Encyclopedia, 1894.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/old-engraved-illustration-of-bees-antique-royalty-free-image/1211227581">mikroman6/Moment via Getty Images</a></span>
</figcaption>
</figure>
<p>During the early 1900s, biologists were aware that <a href="https://us.macmillan.com/books/9781250070975/astinginthetale">flowers attracted bee pollinators by producing certain scents</a>. However, these researchers knew next to nothing about the visual aspects of such attractions, when bees were too far from the flowers to smell them. </p>
<p>To investigate, Turner pounded rows of wooden dowels into the O’Fallon Park lawn. Atop each rod, he affixed a red disk dipped in honey. Soon, bees began traveling from far away to his makeshift “flowers.”</p>
<p>Turner then added a series of “control” rods topped with blue disks that bore no honey. The bees paid little heed to the new “flowers,” <a href="https://doi.org/10.2307/1536088">demonstrating that visual signals provided guidance</a>, when the bees were too distant to smell their targets. Although a <a href="https://doi.org/10.1080/07929978.1997.10676682">honeybee’s ability to detect red remains controversial</a>, scientists have determined that Turner’s bees were likely responding to something called <a href="https://www.encyclo.co.uk/meaning-of-achromatic_stimulus">achromatic stimuli</a>, which <a href="https://doi.org/10.1016/j.cub.2020.08.075">allowed them to discern among various shades and tints</a>.</p>
<h2>Lasting legacies of an underappreciated pioneer</h2>
<p>Turner’s astounding range of findings from three decades of experiments established his reputation as an authority on the <a href="https://psychology.okstate.edu/museum/turner/turnerbio.html">behavioral patterns of bees, cockroaches, spiders and ants</a>.</p>
<p>As a scientific researcher without a university position, he occupied an odd niche. In large part, his situation was the product of systemic racism. It was also a result of his commitment to training young Black students in science. </p>
<p>Alongside his scientific publications, Turner wrote extensively on African American education. In his 1902 essay “<a href="https://books.google.com/books?id=39R1AAAAMAAJ&q=Charles+Henry+Turner#v=snippet&q=Charles%20Henry%20Turner&f=false">Will the Education of the Negro Solve the Race Problem?</a>” Turner contended that trade schools were not the pathway to Black empowerment. Instead, he called for widespread public education of African Americans in all subjects: “if we cast aside our prejudices and try the highest education upon both white and Black, in a few decades there will be no Negro problem.”</p>
<p>Turner was only <a href="https://www.britannica.com/biography/Charles-Henry-Turner">56 when he died of acute myocarditis</a>, an infectious heart inflammation. He was survived by two children and his second wife, Lillian Porter.</p>
<p>Turner’s scientific contributions endure. <a href="https://doi.org/10.4324/9781315802558">His articles continue to be widely cited</a>, and entomologists have subsequently <a href="https://doi.org/10.1038/542031d">verified most of his conclusions</a>.</p>
<p>Despite the colossal challenges he faced throughout his career, Charles Henry Turner was among the first scientists to shed light on the secret lives of bees, the <a href="https://www.penguinrandomhouse.com/books/557206/the-butterfly-effect-by-edward-d-melillo/">winged pollinators that ensure</a> the welfare of human food systems and the survival of Earth’s biosphere.</p><img src="https://counter.theconversation.com/content/184030/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Edward D. Melillo 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>The son of a formerly enslaved mother, Charles Henry Turner was the first to discover that bees and other insects have the ability to modify their behavior based on experience.Edward D. Melillo, William R. Kenan, Jr. Professor of History and Environmental Studies, Amherst CollegeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1875852022-07-26T11:58:35Z2022-07-26T11:58:35ZMonarch butterflies join the Red List of endangered species, thanks to habitat loss, climate change and pesticides<figure><img src="https://images.theconversation.com/files/475922/original/file-20220725-21-ra4ovi.jpg?ixlib=rb-1.1.0&rect=11%2C3%2C2444%2C1634&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Monarch butterflies cluster on a eucalyptus tree at Pismo State Beach's Monarch Butterfly Grove in California. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/monarch-butterflies-cluster-in-eucalyptus-trees-at-pismo-news-photo/1369034696">Ruby Wallau/Getty Images</a></span></figcaption></figure><p><em>On July 21, 2022, the International Union for the Conservation of Nature placed the migratory monarch butterfly on its Red List of threatened species and classified it as <a href="https://www.iucn.org/press-release/202207/migratory-monarch-butterfly-now-endangered-iucn-red-list">endangered</a>. Monarchs migrate across North America each year and are one of the continent’s most widely recognized species. The Conversation asked Oklahoma State University biologist <a href="https://scholar.google.com/citations?user=69XIDjoAAAAJ&hl=en">Kristen Baum</a>, who has studied pollinators for more than 25 years, to explain the listing’s implications for the monarch butterfly in the U.S.</em> </p>
<h2>What is the IUCN, and what does its action mean?</h2>
<p>The IUCN is a network of public, private and nonprofit organizations that <a href="https://www.iucn.org/our-work">work to conserve nature worldwide</a>. The Red List, which was developed in 1964, provides a standardized approach for assessing the extinction risks of species. Listing the monarch butterfly draws attention to its status and to areas where more research is needed to understand factors contributing to its decline. </p>
<p>The IUCN listing applies to the migratory subspecies of the monarch butterfly, or <em>Danaus plexippus plexippus</em>. There are two migratory populations: one east and one west of the Rocky Mountains. </p>
<p>The eastern population migrates thousands of miles from overwintering sites in central Mexico to breeding grounds in the Upper Midwest and southern Canada. The western population migrates from overwintering sites along the Pacific Coast in California and Baja California in Mexico to breeding grounds west of the Rocky Mountains. Monarchs in other locations throughout the world, such as in Europe and many Pacific Islands, don’t migrate and are not part of the listing.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/475923/original/file-20220725-23-4gpno7.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Map of North America showing monarch butterfly fall migration routes." src="https://images.theconversation.com/files/475923/original/file-20220725-23-4gpno7.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/475923/original/file-20220725-23-4gpno7.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=358&fit=crop&dpr=1 600w, https://images.theconversation.com/files/475923/original/file-20220725-23-4gpno7.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=358&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/475923/original/file-20220725-23-4gpno7.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=358&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/475923/original/file-20220725-23-4gpno7.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=450&fit=crop&dpr=1 754w, https://images.theconversation.com/files/475923/original/file-20220725-23-4gpno7.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=450&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/475923/original/file-20220725-23-4gpno7.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=450&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 fall, eastern North American monarchs fly south using several flyways that mostly then merge into a single flyway in central Texas that leads to their overwintering sites in central Mexico. Western monarchs migrate from the Rocky Mountains to overwintering sites on the Pacific Coast.</span>
<span class="attribution"><a class="source" href="https://www.fs.fed.us/wildflowers/pollinators/Monarch_Butterfly/migration/">USFS</a></span>
</figcaption>
</figure>
<h2>What are the main factors threatening monarchs?</h2>
<p>There are many factors <a href="https://www.iucnredlist.org/species/194052138/200522253">contributing to monarchs’ decline</a>. One of the most serious threats is habitat fragmentation and loss. Habitat fragmentation occurs when urban development or agricultural expansion break up large areas of habitat into smaller, often isolated patches. This leaves fewer areas for monarchs to find <a href="https://xerces.org/monarchs/monarch-nectar-plant-guides">the nectar-rich plants that adult butterflies feed on</a>, or <a href="https://www.xerces.org/milkweed/milkweed-guides">milkweed, the sole food source for monarch caterpillars</a>.</p>
<p>Other threats include <a href="https://doi.org/10.3389/fevo.2020.00162">pesticides</a>, <a href="https://doi.org/10.1046/j.1365-2311.2000.00246.x">disease</a>, <a href="https://www.pnas.org/doi/10.1073/pnas.1805114116">climate change</a> and <a href="https://monarchjointventure.org/images/uploads/documents/Swallow-wort_flyer_Updated.pdf">invasive species</a>. Providing more suitable habitat for monarchs in more places could help them tolerate these stresses. </p>
<p>Monarchs are particularly susceptible to threats during the parts of their annual cycle when many millions of them cluster together. For example, a winter storm in March 2016 <a href="https://doi.org/10.1093/ae/tmx052">killed 31%-40% of the monarchs</a> in some overwintering colonies in central Mexico. Winter storms also blow down trees, which can reduce habitat for overwintering colonies in subsequent years. </p>
<p>Temperature and precipitation can influence monarchs’ spring and fall migrations and breeding season success. For example, <a href="https://doi.org/10.1038/s41559-021-01504-1">spring weather</a> is an important factor influencing the size of the summer monarch population. Slightly warmer and drier springs produce more monarchs on the summer breeding grounds. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/lWOySU_hAz0?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Scientists send a hummingbird-shaped drone to film swarming monarch butterflies in Mexico at close range.</span></figcaption>
</figure>
<h2>Are monarch butterflies protected in the US?</h2>
<p>Not yet, although the U.S. Fish and Wildlife Service recognizes that they are at risk. </p>
<p>The agency <a href="https://www.biologicaldiversity.org/species/invertebrates/pdfs/Monarch_ESA_Petition.pdf">received a petition</a> in 2014 to list the monarch butterfly as threatened under the Endangered Species Act. It concluded in 2020 that listing the monarch was <a href="https://www.fws.gov/press-release/2020-12/endangered-species-act-listing-monarch-butterfly-warranted-precluded">warranted but precluded</a>. This means that while monarchs are at risk of extinction, they are less at risk than other species that are currently higher priorities, such as the <a href="https://www.fws.gov/species/rusty-patched-bumble-bee-bombus-affinis">rusty patched bumblebee</a>. </p>
<p>That decision put monarchs on the candidate list, where the agency reviews their status every year. Only a <a href="http://dx.doi.org/%2010.1111/j.1755-263X.2011.00205.x">subset of species</a> on the IUCN Red List is also protected under the Endangered Species Act. For insects, that number is less than 20%.</p>
<p>The <a href="https://www.iucnredlist.org/species/194052138/200522253">IUCN report</a> estimates that the eastern monarch population has declined by 22%-72% over the past decade, and the western population has declined by 66%-91%. Evaluating trends for insect populations can be challenging because they tend to fluctuate from year to year. </p>
<p><div data-react-class="InstagramEmbed" data-react-props="{"url":"https://www.instagram.com/p/CgXCRhVOqkf","accessToken":"127105130696839|b4b75090c9688d81dfd245afe6052f20"}"></div></p>
<p>Another challenge for measuring the populations of migratory species is that patterns can differ depending on when in the annual cycle they are evaluated, such as breeding versus overwintering. To estimate how many eastern monarchs overwinter in central Mexico, scientists measure how many hectares of trees are covered with monarchs and convert that number into an <a href="http://dx.doi.org/10.7717/peerj.3221">estimated number of butterflies</a>. </p>
<p>Many factors influence how densely monarchs cluster together in trees on their overwintering grounds. Estimates based on data from the summer breeding grounds are also challenging because monarchs go through multiple generations per year and breed across a large area.</p>
<h2>Would an ‘endangered’ listing in the US help monarchs?</h2>
<p>Migratory monarchs have a huge range that extends from southern Canada to central Mexico and includes all of the contiguous U.S. They use many types of open habitats, from prairies to urban parks. This makes it challenging to implement and enforce regulatory actions. </p>
<p>The <a href="https://www.iucnredlist.org/species/194052138/200522253">IUCN report</a> points out that the decline of the eastern migratory population seems to have slowed, or even stabilized, over the past 10 years. The <a href="https://www.biologicaldiversity.org/species/invertebrates/pdfs/Monarch_ESA_Petition.pdf">2014 petition</a> to list monarchs under the U.S. Endangered Species Act spurred many actions to support monarchs that likely contributed to slowing their decline, from planting milkweeds and nectar plants in home gardens to <a href="https://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/plantsanimals/pollinate/?cid=nrcseprd402207">large-scale restoration projects</a>. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1550613498937368577"}"></div></p>
<p>Supporting these efforts could <a href="https://doi.org/10.1111/j.1523-1739.2003.00258.x">provide more benefits than a listing</a> under the Endangered Species Act. When a species is listed, the federal government produces a recovery plan that often includes restrictions on actions that threaten the species, such as hunting or land development. Studies have found that private land owners often become <a href="https://doi.org/10.1016/j.rama.2015.08.003">less willing to participate in conservation activities</a>, such as allowing researchers to monitor the species on their property, after a species is listed. </p>
<p>It’s hard to say whether listing monarchs would have this effect. People love monarch butterflies, and community science projects that involve activities like monitoring eggs and caterpillars and tagging monarchs are very popular. Data collected by citizen scientists has <a href="https://doi.org/10.1093/biosci/biv011">expanded what researchers know about monarchs</a>. Many of these efforts have taken place over large areas and long time spans that would be hard for scientists to replicate.</p>
<p>I see community scientists as critical for informing monarch conservation efforts, and hope the IUCN’s action will inspire more people to get involved.</p><img src="https://counter.theconversation.com/content/187585/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kristen Baum receives funding from the Agricultural Biotechnology Stewardship Technical Committee – Non-Target Organism Sub-Committee, Foundation for Food & Agriculture Research, National Park Service, Natural Resources Conservation Service, National Science Foundation, Oklahoma Center for the Advancement of Science & Technology, Oklahoma Department of Wildlife Conservation, Texas Comptroller of Public Accounts, The Nature Conservancy, Transportation Research Board, U.S. Department of Agriculture, U.S. Fish and Wildlife Service, U.S. Forest Service, and U.S. Geological Survey. She has participated in working groups related to monarchs and other pollinators through the Midwest Association of Fish & Wildlife Agencies, Monarch Conservation Science Partnership, Natural Resources Conservation Service, Oklahoma Department of Agriculture Food and Forestry, and Oklahoma Monarch and Pollinator Collaborative.</span></em></p>The iconic monarch butterfly has been added to the Red List of endangered species, but hasn’t received protection in the US yet. That’s not necessarily a bad thing.Kristen A. Baum, Professor of Integrative Biology and Associate Dean for Research, Oklahoma State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1850212022-06-21T02:57:04Z2022-06-21T02:57:04ZWhere do all the mosquitoes go in the winter?<figure><img src="https://images.theconversation.com/files/469915/original/file-20220621-17-wrrp6a.jpg?ixlib=rb-1.1.0&rect=77%2C240%2C5044%2C3205&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://unsplash.com/photos/iuJgEBVSRIo?utm_source=unsplash&utm_medium=referral&utm_content=creditShareLink">Cameron Webb/NSW Health Pathology</a>, <span class="license">Author provided</span></span></figcaption></figure><p>Summer evenings by the pool, lake or BBQ mean mosquitoes. But what about during winter when we’re mostly indoors? As the weather cools, these bloodsucking pests are rarely seen. </p>
<p>But where do they go?</p>
<h2>Warm, wet conditions suit mosquitoes</h2>
<p>Mosquitoes have complex life cycles that rely on water brought to <a href="https://theconversation.com/hidden-housemates-the-mosquitoes-that-battle-for-our-backyards-59072">wetlands, flood plains, and water-holding containers</a> by seasonal rainfall. Depending on whether we’re experiencing a summer under the influence of <a href="https://theconversation.com/will-the-arrival-of-el-nino-mean-fewer-mosquitoes-this-summer-102496">El Niño</a> or <a href="https://theconversation.com/la-nina-will-give-us-a-wet-summer-thats-great-weather-for-mozzies-147180">La Niña</a>, mosquito populations will change in different ways.</p>
<p>During warmer months, their life cycle lasts about a month. Eggs laid around water hatch and the immature mosquitoes go through four developmental stages. Larvae then change to pupae, from which an adult mosquito emerges, sits briefly on the water surface, and then flies off to buzz and bite and continue the cycle. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-worst-year-for-mosquitoes-ever-heres-how-we-find-out-68433">The worst year for mosquitoes ever? Here's how we find out</a>
</strong>
</em>
</p>
<hr>
<p>Water is crucial but temperature is really important too. Unlike warm-blooded animals, mosquitoes can’t control their own body temperatures. The warmer it is, the more active mosquitoes will be. There’s usually more of them about too.</p>
<p>But once cold weather arrives, their activity slows. They fly less, they don’t bite as often, they reproduce less, and their life cycle takes longer to complete.</p>
<p>Temperature also plays a role in determining the ability of mosquitoes to <a href="https://www.frontiersin.org/articles/10.3389/fmicb.2020.584846/full">spread viruses</a>.</p>
<p>Cold weather isn’t great for mosquitoes but <a href="https://www.annualreviews.org/doi/abs/10.1146/annurev-ento-011613-162023">millions of years of evolution</a> have given them a <a href="https://link.springer.com/article/10.1186/s13071-017-2235-0">few tricks to survive</a>. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/468677/original/file-20220614-21-qmcj4w.jpg?ixlib=rb-1.1.0&rect=0%2C43%2C4883%2C3211&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/468677/original/file-20220614-21-qmcj4w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/468677/original/file-20220614-21-qmcj4w.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/468677/original/file-20220614-21-qmcj4w.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/468677/original/file-20220614-21-qmcj4w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/468677/original/file-20220614-21-qmcj4w.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/468677/original/file-20220614-21-qmcj4w.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">Ponds and puddles may be frozen but that doesn’t mean all mosquitoes have disappeared.</span>
<span class="attribution"><a class="source" href="https://unsplash.com/photos/7UYnlgDyf0o">Tom Keldenich/Unsplash</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>Mosquitoes don’t disappear completely</h2>
<p>On a sunny afternoon in winter, you may notice the occasional mosquito buzzing about in your backyard. Not as many as in summer but they’re still around.</p>
<p>Some mosquitoes do disappear. For example, the activity of the pest mosquito <em>Culex annulirostris</em>, thought to play an important role in the <a href="https://theconversation.com/japanese-encephalitis-virus-has-been-detected-in-australian-pigs-can-mozzies-now-spread-it-to-humans-178017">spread of Japanese encephalitis virus</a> in Australia, dramatically declines when temperatures start dropping <a href="https://onlinelibrary.wiley.com/doi/10.1111/j.1442-9993.1980.tb01260.x">below 17.5°C</a>.</p>
<p><a href="https://onlinelibrary.wiley.com/doi/10.1111/aen.12021">Studies in Sydney</a> have shown some mosquitoes, such as <em>Culex annulirostris</em>, disappear. Others, such as <em>Culex quinquefasciatus</em> and <em>Culex molestus</em>, remain active throughout the winter. You just may not notice them (unless they enter your home to buzz about your ears). </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/469917/original/file-20220621-17-k6jyri.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/469917/original/file-20220621-17-k6jyri.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/469917/original/file-20220621-17-k6jyri.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/469917/original/file-20220621-17-k6jyri.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/469917/original/file-20220621-17-k6jyri.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/469917/original/file-20220621-17-k6jyri.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/469917/original/file-20220621-17-k6jyri.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">Some mosquitoes, such as the common Aedes notoscriptus, may occasionally be seen buzzing about in winter.</span>
<span class="attribution"><span class="source">Cameron Webb/NSW Health Pathology</span></span>
</figcaption>
</figure>
<h2>Mosquitoes can disappear into diapause</h2>
<p>We’re familiar with the idea of mammals hibernating through winter but mosquitoes, like many other insects, can enter a phase of inactivity called <a href="https://onlinelibrary.wiley.com/doi/10.1111/eea.12753">diapause</a>. </p>
<p>Once cold weather arrives, adult mosquitoes find hiding places such as tree hollows and animal burrows, within the cracks and crevices of bushland environments, or in garages, basements or other structures around our homes, suburbs and cities. These mosquitoes may only live a few weeks during summer but going into diapause allows them to survive many months through winter.</p>
<p>Mosquitoes can also be found in frozen bodies of water, whether it is a bucket of water in your backyard or a near freezing wetland. For example, there is a group of mosquitoes that belong to the genus <em>Coquillettidia</em> whose <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/jvec.12338">larvae attach</a> to the submerged parts of aquatic plants and can survive the cold winter temperatures. Their development dramatically slows and they’ll stay in the water until spring arrives.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/469888/original/file-20220621-11-eny4r6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/469888/original/file-20220621-11-eny4r6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/469888/original/file-20220621-11-eny4r6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/469888/original/file-20220621-11-eny4r6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/469888/original/file-20220621-11-eny4r6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/469888/original/file-20220621-11-eny4r6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/469888/original/file-20220621-11-eny4r6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/469888/original/file-20220621-11-eny4r6.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">By going into ‘diapause’ adults can survive in places like tree hollows for the cold months.</span>
<span class="attribution"><a class="source" href="https://images.unsplash.com/photo-1625635756778-218152037ccc?ixlib=rb-1.2.1&ixid=MnwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8&auto=format&fit=crop&w=1770&q=80">Unsplash/Pat Whelan</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-can-the-bite-of-a-backyard-mozzie-in-australia-make-you-sick-171601">How can the bite of a backyard mozzie in Australia make you sick?</a>
</strong>
</em>
</p>
<hr>
<h2>All their eggs in one winter basket</h2>
<p>Some mosquitoes make it through the winter thanks to their eggs. Mosquito eggs can be incredibly resilient. They survive being dried out in hot and salty coastal wetlands during summer but also frozen in snow-covered creeks in winter.</p>
<p>In coastal regions of Australia, eggs of the saltmarsh mosquito (<em>Aedes vigilax</em>), sit perfectly safely on soil. Once the weather warms and tides bring in water to the wetlands, these eggs will be ready to hatch.</p>
<p>There is also a special mosquito in Australia known as the “snow melt mosquito” (<em>Aedes nivalis</em>) whose <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1440-6055.1996.tb01371.x">eggs survive under snow</a> and hatch once that snow melts and fills ponds, creeks and wetlands throughout alpine regions.</p>
<h2>Does it matter where mosquitoes go in the winter?</h2>
<p>It also isn’t just the mosquitoes that survive the cold months. Viruses, such as <a href="https://theconversation.com/japanese-encephalitis-virus-can-cause-deadly-brain-swelling-but-in-less-than-1-of-cases-178985">Japanese encephalitis virus</a> or <a href="https://theconversation.com/explainer-what-is-ross-river-virus-24630">Ross River virus</a>, can survive from <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2631767/">summer to summer</a> in mosquito eggs, immature stages, or diapausing adults.</p>
<p>Knowing the seasonal spread of mosquitoes helps health authorities design surveillance and control programs. It may help understand how <a href="https://entomologytoday.org/2022/05/24/snow-covered-tires-help-invasive-mosquitoes-survive-cold-winters/">invasive mosquitoes survive</a> conditions in Australia outside their native ranges by <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0211167">hiding out from the cold</a>, such as in rainwater tanks. </p>
<p>Even mosquitoes typically found in tropical locations can even <a href="https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/1365-2664.13480">adapt to cooler climates</a>.</p>
<p>This knowledge may even expose the chilly chink in mosquito’s armour that we can use to better control mosquito populations and reduce the risks of disease outbreaks.</p><img src="https://counter.theconversation.com/content/185021/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Cameron Webb and the Department of Medical Entomology, NSW Health Pathology, have been engaged by a wide range of insect repellent and insecticide manufacturers to provide testing of products and provide expert advice on mosquito biology. Cameron has also received funding from local, state and federal agencies to undertake research into mosquito-borne disease surveillance and management.</span></em></p>Mosquitoes are commonplace in summer but where do they go once the weather cools? They don’t completely disappear but find fascinating ways to survive the winter.Cameron Webb, Clinical Associate Professor and Principal Hospital Scientist, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1794302022-06-03T12:17:46Z2022-06-03T12:17:46ZBed bugs’ biggest impact may be on mental health after an infestation of these bloodsucking parasites<figure><img src="https://images.theconversation.com/files/466798/original/file-20220602-24-e1ajb7.jpg?ixlib=rb-1.1.0&rect=597%2C134%2C1546%2C704&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Dozens of bed bugs and their eggs and fecal material on a metal bed frame.</span> <span class="attribution"><span class="source">Jerome Goddard</span></span></figcaption></figure><p>Bed bugs are back with a vengeance. After an absence of around 70 years, thanks to effective pesticides such as DDT, they’ve been popping up in fancy hotels, spas, department stores, subway trains, movie theaters – and, of course, people’s homes.</p>
<p><a href="https://scholar.google.com/citations?user=JVfeckwAAAAJ&hl=en&oi=ao">I’m a public health entomologist</a>. In the course of my work, I’ve studied these little bloodsuckers, even letting bed bugs feast on my own appendages in the name of science. <a href="https://www.cc.com/video/5klha6/the-colbert-report-threatdown-bedbugs-environmentalists-jerome-goddard">No one likes dealing with bed bugs</a> – and there are ways to minimize your chances of needing to.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/466795/original/file-20220602-22-q1mksl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="closeup of the front underside of a brown insect" src="https://images.theconversation.com/files/466795/original/file-20220602-22-q1mksl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/466795/original/file-20220602-22-q1mksl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=408&fit=crop&dpr=1 600w, https://images.theconversation.com/files/466795/original/file-20220602-22-q1mksl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=408&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/466795/original/file-20220602-22-q1mksl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=408&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/466795/original/file-20220602-22-q1mksl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=513&fit=crop&dpr=1 754w, https://images.theconversation.com/files/466795/original/file-20220602-22-q1mksl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=513&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/466795/original/file-20220602-22-q1mksl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=513&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Colorized scanning electron microscopic image reveals the underside of a bed bug, including the proboscis (purple) and two eyes (red).</span>
<span class="attribution"><a class="source" href="https://phil.cdc.gov/Details.aspx?pid=11739">CDC/Janice Haney Carr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>Know thy bed bug enemy</h2>
<p>The common bed bug, <em>Cimex lectularius</em>, has been a parasite of humans for thousands of years. Historically, these tiny bloodsuckers were common in human dwellings worldwide, giving the old saying “sleep tight, don’t let the bed bugs bite” real meaning. They had nearly disappeared in developing countries until the mid-1990s, when they began <a href="https://doi.org/10.1093/ae/52.2.102">making a comeback</a> because of restriction or loss of certain pesticides, changes in pest control practices and increased international travel. <a href="https://medent.usyd.edu.au/bedbug/papers/doggett_icup2008.pdf">In many areas</a> around the world, they are now <a href="https://npmapestworld.org/default/assets/File/publicpolicy/executivesummaryreleasetomembersFINAL.pdf">a major urban pest</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/455860/original/file-20220401-30316-7hdfi7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="brown insect on white human skin, eating" src="https://images.theconversation.com/files/455860/original/file-20220401-30316-7hdfi7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/455860/original/file-20220401-30316-7hdfi7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/455860/original/file-20220401-30316-7hdfi7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/455860/original/file-20220401-30316-7hdfi7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/455860/original/file-20220401-30316-7hdfi7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/455860/original/file-20220401-30316-7hdfi7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/455860/original/file-20220401-30316-7hdfi7.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 bed bug extends its beaklike proboscis to feed on human blood.</span>
<span class="attribution"><span class="source">Jerome Goddard</span></span>
</figcaption>
</figure>
<p>Adult bed bugs are less than a quarter-inch long (about 5 mm), oval-shaped and flattened, resembling unfed ticks or small cockroaches. Tucked backward underneath their head they have a long proboscis – a tubular mouthpart they can extend to take a blood meal. A bed bug needs only between three and 10 minutes to <a href="http://ipm.ucanr.edu/PMG/PESTNOTES/pn7454.html">consume up to six times its weight in blood</a> in a single meal.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/455865/original/file-20220401-11604-l3fugz.gif?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Small insect sits on a dime" src="https://images.theconversation.com/files/455865/original/file-20220401-11604-l3fugz.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/455865/original/file-20220401-11604-l3fugz.gif?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=537&fit=crop&dpr=1 600w, https://images.theconversation.com/files/455865/original/file-20220401-11604-l3fugz.gif?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=537&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/455865/original/file-20220401-11604-l3fugz.gif?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=537&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/455865/original/file-20220401-11604-l3fugz.gif?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=675&fit=crop&dpr=1 754w, https://images.theconversation.com/files/455865/original/file-20220401-11604-l3fugz.gif?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=675&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/455865/original/file-20220401-11604-l3fugz.gif?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=675&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 yellowish-white first-stage bed bug nymph is tiny.</span>
<span class="attribution"><span class="source">Jerome Goddard</span></span>
</figcaption>
</figure>
<p>Adults are reddish brown, while the babies are extremely tiny and yellowish-white in color. They hide in cracks and crevices, generally within a few feet of a bed, coming out only to feed on an unsuspecting host. Then they run back to their hiding places, where they mate and lay eggs. </p>
<p>Houses can become infested with thousands of the little bloodthirsty pests in the mattress and box spring, where they leave telltale black fecal spots. In severe infestations there may be thick feces, hundreds of shed skins and eggs several millimeters thick.</p>
<h2>Biggest health impacts may be psychological</h2>
<p>Bed bugs have been <a href="https://doi.org/10.2307/4591852">suspected in the transmission</a> of more than 40 disease organisms, but there is <a href="https://doi.org/10.1001/jama.2009.405">little evidence bed bugs transmit human pathogens</a>, with the <a href="https://doi.org/10.4269/ajtmh.14-0483">possible exception of the microorganism that causes Chagas disease</a>. Extreme infestations can, in rare cases, lead to <a href="https://doi.org/10.1503/cmaj.090482">blood loss severe enough to cause anemia</a>.</p>
<p>Their <a href="https://www.cdc.gov/parasites/bedbugs/faqs.html">principal medical impacts</a> are related to nuisance biting and the associated itching and inflammation. The most common bite reactions are <a href="https://doi.org/10.1016/j.parint.2006.12.002">itchy red spots at feeding sites</a> that usually go away in a week or so. Some people have <a href="https://pubmed.ncbi.nlm.nih.gov/11534921/">complex skin</a> <a href="https://doi.org/10.1007/978-1-4471-1356-0">reactions</a>, <a href="https://doi.org/10.4314/wajm.v21i4.27994">including hives</a> and <a href="https://doi.org/10.1016/j.amjmed.2011.11.020">blisters</a>, or allergic responses.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/455870/original/file-20220401-11-2vzeac.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="pink irritated patch on white skin of an arm" src="https://images.theconversation.com/files/455870/original/file-20220401-11-2vzeac.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/455870/original/file-20220401-11-2vzeac.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/455870/original/file-20220401-11-2vzeac.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/455870/original/file-20220401-11-2vzeac.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/455870/original/file-20220401-11-2vzeac.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/455870/original/file-20220401-11-2vzeac.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/455870/original/file-20220401-11-2vzeac.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">The marks from bed bug bites can persist on human skin for several days.</span>
<span class="attribution"><span class="source">Jerome Goddard and Kristine T. Edwards</span></span>
</figcaption>
</figure>
<p>Then there’s bed bugs’ <a href="http://dx.doi.org/10.1136/bmjopen-2012-000838">emotional and</a> <a href="https://doi.org/10.1016/j.amjmed.2011.08.010">psychological effects on their victims</a>. Run-ins with these parasites can trigger nervousness, anxiety and insomnia. Bed bugs commonly come with a side effect of constant worrying and feelings of shame. <a href="http://habitatservices.org/wp-content/uploads/PDF3-Bed-Bugs-Are-Back-Report.pdf">One distressed Canadian expressed it this way</a>:</p>
<blockquote>
<p>“To be honest, until you go through [an infestation], you have no idea just how horrifying it really is. It is just natural for you to become paranoid; you lose sleep, you end up dreaming and thinking about bed bugs – they just consume every fiber of your being.”</p>
</blockquote>
<p><a href="http://hdl.handle.net/1866/10783">One study of people exposed to bed bugs</a> found about half reported sleep difficulties and social isolation associated with the infestation.</p>
<p>My colleague and I analyzed <a href="https://doi.org/10.1016/j.amjmed.2011.08.010">135 internet posts concerning bed bug infestations</a>. The majority, 81% of the posts, reported three or more behaviors commonly associated with post-traumatic stress disorder – reactions like reexperiencing the event through intrusive memories and nightmares, startle responses and hypervigilance. Six posts detailed intense and repeated cleanings of homes or offices. Five posts reported persistent avoidance of people, activities and places that might lead to transmission of insects or arouse recollections of the original encounter. And five posts detailed suicidal thoughts or attempts. There are other anecdotal reports of <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3700489/">suicides</a> or drug overdoses by people struggling with bed bugs.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/455868/original/file-20220401-19-26i6dl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Bed bugs and fecal spots on a bed sheet." src="https://images.theconversation.com/files/455868/original/file-20220401-19-26i6dl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/455868/original/file-20220401-19-26i6dl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/455868/original/file-20220401-19-26i6dl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/455868/original/file-20220401-19-26i6dl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/455868/original/file-20220401-19-26i6dl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/455868/original/file-20220401-19-26i6dl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/455868/original/file-20220401-19-26i6dl.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">You can check for the telltale marks of a bed bug infestation on a bed’s mattress and box spring.</span>
<span class="attribution"><a class="source" href="https://www.acq.osd.mil/eie/afpmb/docs/techguides/tg44.pdf">H.J. Harlan, U.S. Armed Forces Pest Management Board</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
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<h2>How to protect yourself from bed bugs</h2>
<p>Not every hotel room has bed bugs, but some do. Simple precautions can help protect you and your belongings from infestation. </p>
<p>Leave all unnecessary items in your vehicle, such as extra clothing, gear and equipment. When first entering your hotel room, place luggage in the bathroom until you have had a chance to inspect the place. Pull back sheets and check the mattress and box spring for live bed bugs or black fecal spots. If any bugs or suspicious signs of infestation are found, go to the front desk and request another room. Because bed bugs don’t usually travel far on their own, other nonadjacent rooms may be perfectly clean of the parasites.</p>
<p>Keeping bed bugs out of houses and apartments can be difficult, especially if you travel a lot. After traveling, unpack luggage outside or in the garage, and wash all clothing from the luggage in hot water and dry on high heat if possible. A dryer is a great tool in the fight against bed bugs. Bed bugs can also hitch a ride into your home on used furniture or items purchased at secondhand stores or garage sales. Be sure to disinfect – more precisely “dis-insect” – those kinds of items. It’s a good idea to never purchase used mattresses or beds, no matter how good a bargain. </p>
<p>What can you do if you are forced to confront these bloodsuckers? A bed bug infestation found in a hotel room should immediately be reported to management. If you find bed bugs in your home, or in secondhand purchases, it’s best not to try to spray them yourself with over-the-counter pesticides. My recommendation is to contact a competent pest exterminator, who will treat the space with pesticides, use complex heat systems or both to kill the bugs.</p>
<p>Try not to panic. Keep in mind that bed bugs are only insects. They’re not magic. Believe me, they can be killed and eliminated from a dwelling.</p><img src="https://counter.theconversation.com/content/179430/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jerome Goddard 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>Bed bugs are pretty much universally reviled. But a public health entomologist explains how – while potentially traumatizing to deal with – they aren’t likely to make you sick.Jerome Goddard, Extension Professor of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1828142022-05-11T12:05:04Z2022-05-11T12:05:04ZBeyond honey: 4 essential reads about bees<figure><img src="https://images.theconversation.com/files/462307/original/file-20220510-12-bnz0cm.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C2330%2C1681&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Bumblebees at work, dotted with pollen.</span> <span class="attribution"><a class="source" href="https://flic.kr/p/cFk2Cm">Crabchick/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>As spring gardening kicks into high gear, bees emerge from hibernation and start moving from flower to flower. These hardworking insects play an essential role <a href="https://www.fs.fed.us/wildflowers/pollinators/animals/bees.shtml">pollinating plants</a>, but they’re also interesting for many other reasons. Scientists study bees to learn about their intricate social networks, learning patterns and adaptive behaviors. These four stories from The Conversation’s archive offer diverse views of life in the hive.</p>
<h2>1. Females are the future</h2>
<p>The survival of bee colonies <a href="https://theconversation.com/spring-signals-female-bees-to-lay-the-next-generation-of-pollinators-134852">depends on female bees</a>, although they play different roles depending on their species. In social bee species, females find nesting spots to establish new colonies and lay hundreds of eggs there. </p>
<p>Other species are solitary, meaning that each bee lives alone. Females create segmented nests, lay an egg in each segment, deposit a ball of pollen to feed the larva, and then die off. </p>
<p>Female bees need support, especially early in the year when foraging options are few, doctoral student <a href="https://www.researchgate.net/profile/Lila-Westreich">Lila Westreich</a> notes. “It’s best to provide female bees with many early spring flowers – they rely on nectar from flowers to fuel their search for a nesting spot. Planting early-flowering plants such as willow, poplar, cherry trees and other spring blooms provides nectar for queen bees,” she writes. </p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/spring-signals-female-bees-to-lay-the-next-generation-of-pollinators-134852">Spring signals female bees to lay the next generation of pollinators</a>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/vf8QyIF3eoY?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">In solitary bee species, females play the roles of queen and worker.</span></figcaption>
</figure>
<h2>2. Some bees are curious, others are focused</h2>
<p>All bees forage, but they do it in different ways. Some become very focused on the smell, colors and locations of known food sources and return to those flowers over and over. Others are more willing to explore and will change their behavior when they learn about new food sources. </p>
<p>As part of an experiment, Marquette University biologist <a href="https://scholar.google.com/citations?user=lGDvqJ8AAAAJ&hl=en">Chelsea Cook</a> and her colleagues bred populations of bees that were genetically programmed to be <a href="https://theconversation.com/some-bees-are-born-curious-while-others-are-more-single-minded-new-research-hints-at-how-the-hive-picks-which-flowers-to-feast-on-144900">either curious or focused</a>, and a colony that mixed these two styles together. Then they offered the bees a familiar food source and novel sources. Sure enough, the focused colony concentrated on the familiar source and the curious colony visited both known and novel sources. </p>
<p>In the mixed colony, bees came to concentrate more on the familiar source than the new ones over time. Why? The researchers observed how the bees communicated through their “waggle dance,” which tells nestmates where to find food, and saw that the focused bees were dancing faster. This conveyed their message more intensely than signals from slower dancers.</p>
<p>“Because curious bees are interested in everything, including new information about possible food locations, they are perfect listeners and are easily convinced to visit the chosen feeder of their enthusiastic nestmates,” Cook observes.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/some-bees-are-born-curious-while-others-are-more-single-minded-new-research-hints-at-how-the-hive-picks-which-flowers-to-feast-on-144900">Some bees are born curious while others are more single-minded – new research hints at how the hive picks which flowers to feast on</a>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/12Q8FfyLLso?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">A scientist breaks down bees’ waggle dance.</span></figcaption>
</figure>
<h2>3. It takes a colony</h2>
<p>Bees communicate with one another about <a href="https://theconversation.com/honey-bees-cant-practice-social-distancing-so-they-stay-healthy-in-close-quarters-by-working-together-141106">many things besides food</a>. For example, bees use dancing to persuade their colony to move to a new nest site, write Providence College biologist <a href="https://scholar.google.com/citations?user=B6WmgvLL8vMC&hl=en">Rachael Bonoan</a> and Tufts University biologist <a href="https://scholar.google.com/citations?user=KF4sBDIAAAAJ&hl=en">Phil Starks</a>.</p>
<p>And bees work together to defend their colonies against external threats. Bonoan and Starks analyzed how honeybee colonies of varying sizes protected themselves against a fungus that causes a bee disease called chalkbrood. To do this, the researchers infected the colonies with the fungus and tracked the bees’ responses with thermal imaging.</p>
<p>The pathogen needs cool temperatures to infect bees, so the bees respond with heat. “When this pathogen is detected, worker bees protect the vulnerable young by contracting their large flight muscles to generate heat. This raises the temperature in the brood comb area of the hive just enough to kill the pathogen,” the biologists explain. Worker bees also remove diseased and dead young from the colony, which reduces the chance of infection spreading.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/honey-bees-cant-practice-social-distancing-so-they-stay-healthy-in-close-quarters-by-working-together-141106">Honey bees can't practice social distancing, so they stay healthy in close quarters by working together</a>
</strong>
</em>
</p>
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<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1395430362315067396"}"></div></p>
<h2>4. Straining for the good of the swarm</h2>
<p>Computer scientist <a href="https://scholar.google.com/citations?user=xH5Ryy4AAAAJ&hl=en">Orit Peleg</a> at the University of Colorado Boulder studied yet another way in which bees work together for the good of the group. Peleg and her colleagues analyzed swarms that European honeybees form when a colony becomes so large that it’s about to split into two new groups. The relocating group forms a swarm that can hang from objects such as tree branches, and can change its shape, with each bee essentially holding hands with others next to it.</p>
<p>The scientists used a motor to shake a wooden board with a swarm of 10,000 honeybees hanging from the underside. By seeing how the swarm <a href="https://theconversation.com/what-a-bundle-of-buzzing-bees-can-teach-engineers-about-robotic-materials-125194">responded to shaking in various directions</a>, they hoped to gain insights that could inform the creation of adaptive structures made up of robots linked together. </p>
<p>“Using a computational model, we showed that bonds between bees located closer to where the swarm attaches to the board stretch more than bonds between bees at the far tip of the swarm,” Peleg recounts. “Bees could sense these different amounts of stretching, and use them as a directional signal to move upwards and make the swarm spread.”</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/462309/original/file-20220510-16-hqlk80.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A football-shaped cluster of bees hangs from a branch." src="https://images.theconversation.com/files/462309/original/file-20220510-16-hqlk80.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/462309/original/file-20220510-16-hqlk80.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=806&fit=crop&dpr=1 600w, https://images.theconversation.com/files/462309/original/file-20220510-16-hqlk80.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=806&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/462309/original/file-20220510-16-hqlk80.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=806&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/462309/original/file-20220510-16-hqlk80.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1013&fit=crop&dpr=1 754w, https://images.theconversation.com/files/462309/original/file-20220510-16-hqlk80.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1013&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/462309/original/file-20220510-16-hqlk80.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1013&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Bee swarm on a tree branch in Arkansas.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Swarming_(honey_bee)#/media/File:Bee_Swarm.JPG">Mark Osgathard/Wikipedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>Put another way, the bees moved from locations where bonds stretched less to locations where they stretched more. “This behavioral response improves the collective stability of the swarm as a whole at the expense of increasing the average burden experienced by the individual bee,” Peleg concludes. </p>
<p>They found that when they shook the board horizontally, the swarm spread out into a wider, more stable cone. But it was less able to react to vertical shaking and eventually broke apart. That’s because vertical shaking didn’t disrupt the bonds between individual bees as much as horizontal shaking, so the swarm didn’t respond to vertical shaking by changing its shape.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/what-a-bundle-of-buzzing-bees-can-teach-engineers-about-robotic-materials-125194">What a bundle of buzzing bees can teach engineers about robotic materials</a>
</strong>
</em>
</p>
<hr>
<p><em>Editor’s note: This story is a roundup of articles from The Conversation’s archive.</em></p><img src="https://counter.theconversation.com/content/182814/count.gif" alt="The Conversation" width="1" height="1" />
Bees offer insights into many scientific questions, from cooperating in close quarters to strategies for finding food.Jennifer Weeks, Senior Environment + Cities Editor, The ConversationLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1762412022-05-10T20:01:12Z2022-05-10T20:01:12ZThe book that changed me: how field guides showed me the awe-inspiring diversity of insects<figure><img src="https://images.theconversation.com/files/461911/original/file-20220509-21-ckdpcr.jpg?ixlib=rb-1.1.0&rect=22%2C0%2C3765%2C2252&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Close up of a citrus swallowtail butterfly.</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p><em>In this series, writers nominate a book that changed their life – or at least their thinking.</em></p>
<p>I am an avid reader and have devoured many books over the years, especially science fiction. For me, reading is about escapism; it’s an opportunity to explore strange new worlds and discover new ideas and new futures. </p>
<p>Yet the book that changed my life wasn’t about far away planets or alien civilisations; instead, it introduced me to a strange and beautiful world that existed all around me.</p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/461875/original/file-20220509-12-n3pqqb.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/461875/original/file-20220509-12-n3pqqb.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/461875/original/file-20220509-12-n3pqqb.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=937&fit=crop&dpr=1 600w, https://images.theconversation.com/files/461875/original/file-20220509-12-n3pqqb.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=937&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/461875/original/file-20220509-12-n3pqqb.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=937&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/461875/original/file-20220509-12-n3pqqb.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1178&fit=crop&dpr=1 754w, https://images.theconversation.com/files/461875/original/file-20220509-12-n3pqqb.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1178&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/461875/original/file-20220509-12-n3pqqb.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1178&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<p><a href="https://www.google.com.au/books/edition/A_Field_Guide_to_Insects/BkG5T2tg6B4C?hl=en">Peterson’s A Field Guide to the Insects of America North of Mexico</a> by Donald J. Borror and Richard E. White opened my eyes to a hidden world populated by an unimaginable cast of fantastic creatures.</p>
<p>In its pages, I learned about the <a href="https://www.wired.com/2015/01/absurd-creature-of-the-week-strepsiptera/">deeply bizarre</a> “twisted wing parasites” (<a href="https://en.wikipedia.org/wiki/Strepsiptera">order <em>Strepsiptera</em></a>) who live most of their peculiar lives inside the rear ends of other insects; the webspinning <a href="https://en.wikipedia.org/wiki/Embioptera">Embioptera</a> who collectively weave gossamer nests out of silk they shoot from their forelegs; and the tiny and <a href="https://thesmallermajority.com/2014/05/27/my-life-is-now-complete/">ultra-enigmatic</a> “angel insects” (<a href="https://en.wikipedia.org/wiki/Zoraptera">order <em>Zoraptera</em></a>), which live in small social groups beneath the bark of rotting logs. </p>
<p>I learned that the everyday world was full of creatures every bit as bizarre and interesting as science fiction aliens. The Earth was so much more diverse – and weird – than I’d ever imagined. </p>
<p>I first encountered Field Guide to the Insects as a budding biology student who loved searching for creepy crawlies under logs and rocks. I was excited by the prospect that, field guide in hand, I would finally be able to put a name to every single one of the insects I saw on my outdoor explorations. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/462168/original/file-20220510-16-pjijco.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/462168/original/file-20220510-16-pjijco.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/462168/original/file-20220510-16-pjijco.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=443&fit=crop&dpr=1 600w, https://images.theconversation.com/files/462168/original/file-20220510-16-pjijco.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=443&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/462168/original/file-20220510-16-pjijco.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=443&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/462168/original/file-20220510-16-pjijco.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=557&fit=crop&dpr=1 754w, https://images.theconversation.com/files/462168/original/file-20220510-16-pjijco.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=557&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/462168/original/file-20220510-16-pjijco.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=557&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 author with a millipede, circa 2002.</span>
<span class="attribution"><span class="source">Author provided</span></span>
</figcaption>
</figure>
<p>One of the first things this book taught me was how impossible that task was. At the time it was first written (1970), there were 88,600 named species of insect in North America; today, that number likely exceeds <a href="https://www.si.edu/spotlight/buginfo/bugnos#:%7E:text=At%20any%20time%2C%20it%20is,is%20estimated%20at%20some%2073%2C000.">100,000 </a>. </p>
<p>Globally, there are 900,000 described species of insects, making them by far the most diverse group of animals on our planet. Even the most dedicated entomologist would struggle to identify every insect species they encounter; there are simply too many.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/461910/original/file-20220509-20-mhqfs8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/461910/original/file-20220509-20-mhqfs8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/461910/original/file-20220509-20-mhqfs8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=458&fit=crop&dpr=1 600w, https://images.theconversation.com/files/461910/original/file-20220509-20-mhqfs8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=458&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/461910/original/file-20220509-20-mhqfs8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=458&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/461910/original/file-20220509-20-mhqfs8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=575&fit=crop&dpr=1 754w, https://images.theconversation.com/files/461910/original/file-20220509-20-mhqfs8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=575&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/461910/original/file-20220509-20-mhqfs8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=575&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Embioptera weave gossamer nests out of silk they shoot from their forearms.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/climate-change-triggering-global-collapse-in-insect-numbers-stressed-farmland-shows-63-decline-new-research-170738">Climate change triggering global collapse in insect numbers: stressed farmland shows 63% decline – new research</a>
</strong>
</em>
</p>
<hr>
<h2>Powerful and precious</h2>
<p>Field Guide to the Insects navigates the overwhelming number of insect species by focusing on the identification of broad insect groups called “<a href="https://anic.csiro.au/insectfamilies/">families</a>”. The 1,300 drawings and 142 stunning colour images taught me to recognise the most common insects around me.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/461907/original/file-20220509-1215-6eoga3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/461907/original/file-20220509-1215-6eoga3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/461907/original/file-20220509-1215-6eoga3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=750&fit=crop&dpr=1 600w, https://images.theconversation.com/files/461907/original/file-20220509-1215-6eoga3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=750&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/461907/original/file-20220509-1215-6eoga3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=750&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/461907/original/file-20220509-1215-6eoga3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=943&fit=crop&dpr=1 754w, https://images.theconversation.com/files/461907/original/file-20220509-1215-6eoga3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=943&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/461907/original/file-20220509-1215-6eoga3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=943&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Migrating Monarch butterflies on their way to Mexico.</span>
<span class="attribution"><span class="source">Chip Taylor/AP</span></span>
</figcaption>
</figure>
<p>I found myself discovering amazing new insects everywhere I looked. The animals I found were not new to science; they were common species, and I had been surrounded by them my entire life. I had just never noticed. </p>
<p>To me, that’s the power of field guides; they help us uncover the hidden diversity of our world. Our little planet is absolutely teaming with a riotous diversity of life forms.</p>
<p>I’ve learned that the knowledge a field guide provides can be powerful and precious. Thanks to a field guide, I know that the leggy spider hanging in my bathroom is a harmless <a href="https://australian.museum/learn/animals/spiders/daddy-long-legs-spider/">daddy long legs (<em>Pholcus phalangioides</em>)</a> and that the weird caterpillar that looks like bird droppings on my lemon tree will one day become an elegant citrus swallowtail butterfly (<em><a href="https://en.wikipedia.org/wiki/Papilio_aegeus">Papilio aegeus</a></em>) . </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/461924/original/file-20220509-24-hbk2zc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/461924/original/file-20220509-24-hbk2zc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/461924/original/file-20220509-24-hbk2zc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=446&fit=crop&dpr=1 600w, https://images.theconversation.com/files/461924/original/file-20220509-24-hbk2zc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=446&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/461924/original/file-20220509-24-hbk2zc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=446&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/461924/original/file-20220509-24-hbk2zc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=560&fit=crop&dpr=1 754w, https://images.theconversation.com/files/461924/original/file-20220509-24-hbk2zc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=560&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/461924/original/file-20220509-24-hbk2zc.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">From ugliness to elegance … the caterpillar that becomes a citrus swallowtail butterfly.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>A field guide taught me that the <a href="https://en.wikipedia.org/wiki/Blue-ringed_octopus">tiny octopus</a> flashing blue in a local tide-pool was best admired from a distance. At a time when engagement with nature appears to be declining (particularly in urban areas), field guides provide us with the opportunity to connect deeply with it. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-book-that-changed-me-journeying-to-the-self-with-ana-s-nins-sensual-transgressive-diaries-176135">The book that changed me: journeying to the self with Anaïs Nin's sensual, transgressive diaries</a>
</strong>
</em>
</p>
<hr>
<h2>From opera glasses to apps</h2>
<p>Field guides make specialist knowledge accessible to non-professional audiences; empowering us to explore nature no matter what our background, education or employment.</p>
<p>But prior to the 1890’s, most guides to animals and plants were written exclusively for professional scientists. They used dense technical language to describe often minute differences between specimens, many of which could only be observed as dead animals. </p>
<p>In the late 1800’s two books, <a href="https://www.google.com.au/books/edition/Birds_Through_an_Opera_Glass/r6gaAAAAYAAJ?hl=en&gbpv=1&printsec=frontcover">Birds Through an Opera Glass</a> (Florence Merriam Bailey ) and <a href="https://www.metmuseum.org/art/collection/search/405911">How to Know the Wildflowers</a> (Frances Theodora Parsons) became the first modern field guides written for recreational nature-watchers. </p>
<figure class="align-left zoomable">
<a href="https://images.theconversation.com/files/461913/original/file-20220509-15-6eoga3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/461913/original/file-20220509-15-6eoga3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/461913/original/file-20220509-15-6eoga3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=594&fit=crop&dpr=1 600w, https://images.theconversation.com/files/461913/original/file-20220509-15-6eoga3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=594&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/461913/original/file-20220509-15-6eoga3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=594&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/461913/original/file-20220509-15-6eoga3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=746&fit=crop&dpr=1 754w, https://images.theconversation.com/files/461913/original/file-20220509-15-6eoga3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=746&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/461913/original/file-20220509-15-6eoga3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=746&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Florence Merriam Bailey photographed in 1886.</span>
</figcaption>
</figure>
<p>Both books featured accessible language and illustrations aimed at helping non-professionals identify plants and animals in the field.</p>
<p>In 1934, Roger Tory <a href="https://blog.library.si.edu/blog/2018/12/04/spotting-a-first-edition-of-petersons-a-field-guide-to-the-birds/#.YhToQehBzb0">Peterson</a> revolutionised the way field guides approached identification with his Field Guide to the Birds. It featured two key innovations: the grouping of similar-looking birds on a single page, and the use of arrows to point out distinguishing features. </p>
<p>The <a href="https://en.wikipedia.org/wiki/Peterson_Identification_System">Peterson’s identification system</a> has since been adapted and used by hundreds of field guides.</p>
<p>In recent years, field guides have been joined by automated identification apps such as <a href="https://www.inaturalist.org/">iNaturalist</a>, <a href="https://www.plantsnap.com/">PlantSnap</a>, <a href="https://merlin.allaboutbirds.org/">Merlin BirdID</a> and <a href="https://www.frogid.net.au/">FrogID</a> that use sophisticated algorithms to identify organisms using photos or audio clips. Some apps, like iNaturalist, can identify an enormous range of organisms, far beyond the scope of even the most ambitious guide. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/461919/original/file-20220509-14-mevi76.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/461919/original/file-20220509-14-mevi76.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/461919/original/file-20220509-14-mevi76.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=430&fit=crop&dpr=1 600w, https://images.theconversation.com/files/461919/original/file-20220509-14-mevi76.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=430&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/461919/original/file-20220509-14-mevi76.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=430&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/461919/original/file-20220509-14-mevi76.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=540&fit=crop&dpr=1 754w, https://images.theconversation.com/files/461919/original/file-20220509-14-mevi76.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=540&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/461919/original/file-20220509-14-mevi76.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=540&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Apps can now identify an enormous range of organisms.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>Plants, slime moulds, spiders, fungi</h2>
<p>Do these apps replace field guides? I don’t think so. I see apps and field guides as complementary tools that enhance my explorations of nature. Flipping through a field guide helps me to learn the gestalt of features that identifies a group of organisms. Field guides allow for this kind of learning in a way that apps currently do not. </p>
<p>I still have my old copy of Peterson’s field guide , though I rarely use it now. As a professional entomologist, I’ve learned to use more sophisticated identification tools. But I still collect field guides to other groups – plants, slime moulds, spiders, fungi – I am not an expert at identifying. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/461921/original/file-20220509-18-utx0j8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/461921/original/file-20220509-18-utx0j8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/461921/original/file-20220509-18-utx0j8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/461921/original/file-20220509-18-utx0j8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/461921/original/file-20220509-18-utx0j8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/461921/original/file-20220509-18-utx0j8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/461921/original/file-20220509-18-utx0j8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/461921/original/file-20220509-18-utx0j8.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">Field guides can help identify funghi too.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>Field guides taught me to see the world in all its weird and wonderful diversity. Knowing that I am surrounded by a teeming multitude of unique life forms has made my life so much richer.</p><img src="https://counter.theconversation.com/content/176241/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tanya Latty receives funding from the Australian Research Council and the Herman Slade foundation. She is affiliated with the Australian Entomological Society, the Australasian Society for the Study of Animal Behaviour, and the not-for-profit organisation Invertebrates Australia.</span></em></p>There are 900,000 described species of insects in the world. Field guides help us make sense of them.Tanya Latty, Associate professor, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1771182022-03-28T12:37:55Z2022-03-28T12:37:55ZHow did cockroaches survive the asteroid that led to the extinction of dinosaurs?<figure><img src="https://images.theconversation.com/files/453979/original/file-20220323-19-1ijv5iq.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C5000%2C3495&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Artist's rendering of the Chicxulub asteroid entering Earth's atmosphere 66 million years ago, triggering events that caused a mass extermination.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/illustration/end-of-cretaceous-kt-event-illustration-royalty-free-illustration/724237133">Roger Harris/Science Photo library via Getty Images</a></span></figcaption></figure><figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=293&fit=crop&dpr=1 600w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=293&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=293&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=368&fit=crop&dpr=1 754w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=368&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=368&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p><em><a href="https://theconversation.com/us/topics/curious-kids-us-74795">Curious Kids</a> is a series for children of all ages. If you have a question you’d like an expert to answer, send it to <a href="mailto:curiouskidsus@theconversation.com">curiouskidsus@theconversation.com</a>.</em></p>
<hr>
<blockquote>
<p><strong>How did cockroaches survive the asteroid that led to the extinction of dinosaurs? – Kinjal, age 11, Delhi, India</strong></p>
</blockquote>
<p>When the rock now known as the <a href="https://www.nytimes.com/2021/09/13/science/chicxulub-dinosaur-extinction.html">Chicxulub impactor</a> plummeted from outer space and slammed into the Earth 66 million years ago, cockroaches were there. The impact caused a massive earthquake, and scientists think it also <a href="https://theconversation.com/more-bad-news-for-dinosaurs-chicxulub-meteorite-impact-triggered-global-volcanic-eruptions-on-the-ocean-floor-91053">triggered volcanic eruptions</a> thousands of miles from the impact site. Three-quarters of plants and animals on Earth died, including all dinosaurs, <a href="https://www.birdlife.org/news/2021/12/21/its-official-birds-are-literally-dinosaurs-heres-how-we-know/">except for some species</a> that were ancestors of today’s birds.</p>
<p>How could roaches a couple of inches long survive when so many powerful animals went extinct? It turns out that they were nicely equipped to live through a meteoric catastrophe.</p>
<p>If you’ve ever seen a cockroach, you’ve probably noticed that their bodies are very flat. This is not an accident. Flatter insects can squeeze themselves into tighter places. This enables them to hide practically anywhere – and it may have helped them survive the Chicxulub impact.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/1ro6PNqkHEM?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Cockroaches have flat bodies that help them squeeze through tiny spaces. They’re also strong and fast.</span></figcaption>
</figure>
<p>When the meteor struck, <a href="https://www.smithsonianmag.com/science-nature/dinosaur-killing-asteroid-impact-chicxulub-crater-timeline-destruction-180973075/">temperatures on Earth’s surface skyrocketed</a>. Many animals had nowhere to flee, but roaches could take shelter in tiny soil crevices, which provide excellent protection from heat.</p>
<p>The meteor’s impact <a href="https://www.livescience.com/dinosaur-killing-asteroid-struck-earth">triggered a cascade of effects</a>. It kicked up so much dust that the sky darkened. As the sun dimmed, temperatures plunged and conditions became wintry around the globe. With little sunlight, surviving plants struggled to grow, and many other organisms that relied on those plants went hungry. </p>
<p>Not cockroaches, though. Unlike some insects that <a href="https://www.fs.fed.us/wildflowers/pollinators/pollinator-of-the-month/yucca_moths.shtml">prefer to eat one specific plant</a>, cockroaches are <a href="https://cockroachfacts.com/what-do-cockroaches-eat/">omnivorous scavengers</a>. This means they will eat most foods that come from animals or plants as well as cardboard, some kinds of clothing and even poop. Having appetites that aren’t picky has allowed cockroaches to survive lean times since the Chicxulub extinction and other natural disasters.</p>
<p>Another helpful trait is that cockroaches <a href="https://extension.umn.edu/insects-infest-homes/cockroaches">lay their eggs in little protective cases</a>. These egg cartons look like dried beans and are called oothecae, which means “egg cases.” Like phone cases, oothecae are hard and protect their contents from physical damage and other threats, such as flooding and drought. Some cockroaches may have waited out part of the Chicxulub catastrophe from the comfort of their oothecae. </p>
<figure class="align-right ">
<img alt="Small brown rectangular egg case on white background" src="https://images.theconversation.com/files/453995/original/file-20220323-17-10395k5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/453995/original/file-20220323-17-10395k5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/453995/original/file-20220323-17-10395k5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/453995/original/file-20220323-17-10395k5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/453995/original/file-20220323-17-10395k5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/453995/original/file-20220323-17-10395k5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/453995/original/file-20220323-17-10395k5.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">Cockroach egg cases are about 0.5 inches long (10 millimeters) and contain up to 50 eggs, depending on the species.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/ootheca-of-cockroach-isolated-on-white-royalty-free-image/488873689">VitalisG/iStock via Getty Images</a></span>
</figcaption>
</figure>
<p>Modern cockroaches are little survivors that can live just about anywhere on land, from the heat of the tropics to some of the coldest parts of the globe. Scientists estimate that <a href="https://bugguide.net/node/view/342386">there over 4,000 cockroach species</a>. </p>
<p>A handful of these species like to live with humans and quickly become pests. Once cockroaches become established in a building, it’s hard to rid every little crack of these insects and their oothecae. When large numbers of roaches are present in unsanitary places, they can spread diseases. The biggest threat they pose to human health is from allergens they produce that can <a href="https://www.nytimes.com/2018/08/03/science/cockroach-diseases.html">trigger asthma attacks and allergic reactions</a> in some people.</p>
<p>Cockroach pests are hard to manage because they can <a href="https://www.nationalgeographic.com/animals/article/pesticides-are-making-german-cockroaches-stronger">resist many chemical insecticides</a> and because they have the same abilities that helped their ancestors outlive many dinosaurs. Still, cockroaches are much more than a pest to control. Researchers study cockroaches to understand <a href="https://news.umich.edu/lessons-from-cockroaches-could-inform-robotics/">how they move</a> and <a href="https://www.nytimes.com/2016/02/09/science/cockroaches-indestructible-and-instructive-to-robot-makers.html">how their bodies are designed</a> to get ideas for building better robots.</p>
<p><a href="https://www.researchgate.net/profile/Brian-Lovett">As a scientist</a>, I see all insects as beautiful, six-legged inspirations. Cockroaches have already overcome odds that were too great for dinosaurs. If another meteorite hit the Earth, I’d be more worried for humans than for cockroaches.</p>
<hr>
<p><em>Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to <a href="mailto:curiouskidsus@theconversation.com">CuriousKidsUS@theconversation.com</a>. Please tell us your name, age and the city where you live.</em></p>
<p><em>And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.</em></p><img src="https://counter.theconversation.com/content/177118/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Brian Lovett 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>Cockroaches have been on Earth far longer than humans and may outlast us. Here are a few reasons why.Brian Lovett, Postdoctoral Researcher in Mycology, West Virginia UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1685492021-11-08T13:43:51Z2021-11-08T13:43:51ZDo flies really throw up on your food when they land on it?<figure><img src="https://images.theconversation.com/files/423207/original/file-20210925-14-1yipuw9.jpg?ixlib=rb-1.1.0&rect=115%2C121%2C3765%2C2445&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A fly regurgitating digestive juices.</span> <span class="attribution"><span class="source">Carlos Ruiz</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=293&fit=crop&dpr=1 600w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=293&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=293&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=368&fit=crop&dpr=1 754w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=368&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=368&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p><em><a href="https://theconversation.com/us/topics/curious-kids-us-74795">Curious Kids</a> is a series for children of all ages. If you have a question you’d like an expert to answer, send it to <a href="mailto:curiouskidsus@theconversation.com">curiouskidsus@theconversation.com</a>.</em></p>
<hr>
<blockquote>
<p><strong>Do flies really throw up on my food when they land on it? – Henry E., age 10, Somerville, Massachusetts</strong></p>
</blockquote>
<hr>
<p>Imagine you’re at a picnic and just about to bite into your sandwich. Suddenly you spot a fly headed your way, homing in on your food with help from its <a href="https://askentomologists.com/2015/02/25/through-the-compound-eye/">compound eyes</a> and antennae. It manages to escape your swatting, lands on the sandwich and then seems to throw up on it!</p>
<p>It can look kind of gross, but the fly might be just airing out its own digested food, or <a href="https://doi.org/10.1093/aesa/90.2.184">spitting on yours</a>.</p>
<p>Most of the <a href="https://www.si.edu/spotlight/buginfo/true-flies-diptera">over 110,000</a> known fly species <a href="https://doi.org/10.1673/031.008.7301">have no teeth</a>, so they cannot chew solid food. Their mouthparts are like a spongy straw. Once they land on your food, they need to release digestive juices to liquefy it into a predigested, slurpable soup they can swallow. In short, some flies are on a <a href="https://doi.org/10.1673/031.008.7301">liquid diet</a>.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/N23E4jYTExk?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">A fly slurping its liquid meal.</span></figcaption>
</figure>
<p>To fit more food in their stomachs, some flies try to reduce the liquid in what they have already eaten. They regurgitate food into vomit bubbles to dry it out a bit. Once <a href="https://doi.org/10.1111/j.1365-3032.1992.tb01193.x">some water has evaporated</a> they can ingest this more concentrated food. </p>
<p>Human beings don’t need to do all this spitting and regurgitating to get nutrients out of our food. But you do produce a digestive juice in your saliva, an enzyme called <a href="https://1md.org/health-guide/digestive/ingredients/alpha-amylase">amylase</a>, which predigests some of the sandwich bread while you chew. Amylase breaks down starch, which you can’t taste, into simple sugars like glucose, which you can taste. That’s why <a href="https://doi.org/10.1093/chemse/bjz010">bread gets sweeter</a> the longer you chew it. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/423212/original/file-20210925-23-18a0vfd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="closeup of a reddish insect with bristly black hairs on its body" src="https://images.theconversation.com/files/423212/original/file-20210925-23-18a0vfd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/423212/original/file-20210925-23-18a0vfd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=459&fit=crop&dpr=1 600w, https://images.theconversation.com/files/423212/original/file-20210925-23-18a0vfd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=459&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/423212/original/file-20210925-23-18a0vfd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=459&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/423212/original/file-20210925-23-18a0vfd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=577&fit=crop&dpr=1 754w, https://images.theconversation.com/files/423212/original/file-20210925-23-18a0vfd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=577&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/423212/original/file-20210925-23-18a0vfd.jpg?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">Bristles and hair on a Tachinid fly.</span>
<span class="attribution"><span class="source">Maria Cleopatra Pimienta</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Did you know flies can taste food without their mouths? As soon as they land, they use receptors on their feet to decide whether they’re on something nutritious. You may have noticed a fly rubbing its legs together, like a hungry customer getting ready to devour a meal. <a href="https://doi.org/10.1016/j.cub.2020.01.045">This is called grooming</a> – the fly is essentially cleaning itself, and may also clean the <a href="https://doi.org/10.1016/j.conb.2009.07.001">taste sensors</a> on the <a href="https://doi.org/10.1523/JNEUROSCI.0649-14.2014">bristles and fine hair of its feet</a>, to get a better idea of what is in the food it has landed on.</p>
<h2>Should you trash food a fly’s landed on?</h2>
<p>When a fly touches down on your sandwich, that’s probably not the only thing it’s landed on that day. Flies often sit on gross stuff, like a dumpster or decomposing food, that’s full of microbes. The germs can hitch a ride and, if the fly stays put long enough, hop onto your meal. This is much more dangerous than their saliva because <a href="https://doi.org/10.1038/s41598-017-16353-x">some of the microbes</a> can cause diseases, like <a href="https://doi.org/10.1016/j.vaccine.2019.07.078">cholera</a> and <a href="https://doi.org/10.1353/pbm.2006.0005">typhoid</a>. But if the fly doesn’t stay longer than a few seconds the <a href="https://theconversation.com/should-i-throw-away-food-once-a-fly-has-landed-on-it-50895">chances of microbes transferring are low</a>, and your food is probably fine. </p>
<p>To keep insects from landing on your food, you should always cover it. If your house is infested with flies, you can use <a href="https://theconversation.com/how-to-kill-fruit-flies-according-to-a-scientist-81740">simple traps</a> to get rid of them. Carnivorous plants can also eat the flies and help control their population.</p>
<h2>Are flies good for anything?</h2>
<p>Spitting on food and spreading diseases sounds disgusting, but flies aren’t all bad. </p>
<p>Watch closely the next time you’re outside and you might be surprised by how many flies visit flowers to get nectar. They’re an important group of <a href="https://doi.org/10.3390/insects11060341">pollinators</a>, and many plants need flies to <a href="https://theconversation.com/tiny-cacao-flowers-and-fickle-midges-are-part-of-a-pollination-puzzle-that-limits-chocolate-production-154334">help them reproduce</a>.</p>
<p>Flies are also a good source of food for frogs, lizards, spiders and birds, so they’re a valuable <a href="https://doi.org/10.1002/ps.5807">part of the ecosystem</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/429602/original/file-20211101-25-1rfhnd6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="doctor working on patient's foot in background, tubes of maggots in foreground" src="https://images.theconversation.com/files/429602/original/file-20211101-25-1rfhnd6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/429602/original/file-20211101-25-1rfhnd6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=422&fit=crop&dpr=1 600w, https://images.theconversation.com/files/429602/original/file-20211101-25-1rfhnd6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=422&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/429602/original/file-20211101-25-1rfhnd6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=422&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/429602/original/file-20211101-25-1rfhnd6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=531&fit=crop&dpr=1 754w, https://images.theconversation.com/files/429602/original/file-20211101-25-1rfhnd6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=531&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/429602/original/file-20211101-25-1rfhnd6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=531&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 doctor uses sterile maggots like those in these tubes to clean a patient’s foot wound.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/steril-gezüchtete-maden-im-vordergrund-in-reagenzgläsern-zu-news-photo/1213178783">Norbert Försterling/picture alliance via Getty Images</a></span>
</figcaption>
</figure>
<p>Some <a href="https://doi.org/10.1134/S0013873819030023">flies have medical uses</a>, too. For example, doctors use blow fly maggots – the young, immature form of flies – to remove decomposing tissue in wounds. The maggots release antiviral and antimicrobial juices, and these have helped scientists create new treatments for infections.</p>
<p>More importantly, the fruit flies you may have seen flying around ripe bananas in your kitchen have been <a href="https://theconversation.com/ode-to-the-fruit-fly-tiny-lab-subject-crucial-to-basic-research-38465">invaluable in biological research</a>. Biomedical scientists from all over the world study fruit flies to find <a href="https://doi.org/10.1016/S1369-7021(11)70113-4">causes and cures for diseases and genetic disorders</a>. And in <a href="https://faculty.fiu.edu/%7Etheobald/people/">our lab</a>, we study what the world looks like to insects, and how they use their vision to fly. This knowledge can inspire engineers to build better robots.</p>
<p>So, although it’s a nuisance to shoo flies away from your sandwich, maybe you can spare a few bits of your lunch?</p>
<hr>
<p><em>Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to <a href="mailto:curiouskidsus@theconversation.com">CuriousKidsUS@theconversation.com</a>. Please tell us your name, age and the city where you live.</em></p>
<p><em>And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.</em></p><img src="https://counter.theconversation.com/content/168549/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jamie Theobald receives funding from the National Science Foundation: IOS-1750833. </span></em></p><p class="fine-print"><em><span>Ravindra Palavalli-Nettimi 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>A fly does some of its digesting outside its body before it even eats any food.Ravindra Palavalli-Nettimi, Postdoctoral Research Associate, Florida International UniversityJamie Theobald, Associate Professor of Biological Sciences, Florida International UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1584032021-08-27T12:30:54Z2021-08-27T12:30:54ZThe invasive emerald ash borer has destroyed millions of trees – scientists aim to control it with tiny parasitic wasps<figure><img src="https://images.theconversation.com/files/417871/original/file-20210825-15-1ja4r42.jpg?ixlib=rb-1.1.0&rect=25%2C0%2C4255%2C2843&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Emerald ash borer larva cut these feeding galleries on the trunk of a dead ash tree in Michigan. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/emerald-ash-borer-traces-on-a-dead-tree-trunk-royalty-free-image/157602074">corfoto via Getty Images</a></span></figcaption></figure><p>The emerald ash borer (<em>Agrilus planipennis</em>) is a deceptively attractive metallic-green adult beetle with a red abdomen. But few people ever actually see the insect itself – just the trail of destruction it leaves behind under the bark of ash trees. </p>
<p>These insects, which are native to Asia and Russia, were first discovered in Michigan in 2002. Since then they have spread to 35 states and become the <a href="https://www.aphis.usda.gov/aphis/ourfocus/planthealth/plant-pest-and-disease-programs/pests-and-diseases/emerald-ash-borer">most destructive and costly invasive wood-boring insect</a> in U.S. history. They have also been detected in the Canadian provinces of <a href="https://www.invasivespeciescentre.ca/invasive-species/meet-the-species/invasive-insects/emerald-ash-borer/">Ontario, Quebec, Manitoba, New Brunswick and Nova Scotia</a>. </p>
<p>In 2021 the U.S. Department of Agriculture <a href="https://www.federalregister.gov/documents/2020/12/15/2020-26734/removal-of-emerald-ash-borer-domestic-quarantine-regulations">stopped regulating the movement of ash trees and wood products in infested areas</a> because the beetles <a href="https://youtu.be/VYMsSefX-qc">spread rapidly despite quarantine efforts</a>. Now federal regulators and researchers are pursuing a different strategy: biological control. Scientists think that <a href="https://www.nrs.fs.fed.us/disturbance/invasive_species/eab/control_management/biological_control/">tiny parasitic wasps</a>, which prey on emerald ash borers in their native range, hold the key to curbing this invasive species and returning ash trees to North American forests. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/417872/original/file-20210825-23-1khh9n5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Metallic green beetle." src="https://images.theconversation.com/files/417872/original/file-20210825-23-1khh9n5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/417872/original/file-20210825-23-1khh9n5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=1042&fit=crop&dpr=1 600w, https://images.theconversation.com/files/417872/original/file-20210825-23-1khh9n5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=1042&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/417872/original/file-20210825-23-1khh9n5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=1042&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/417872/original/file-20210825-23-1khh9n5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1309&fit=crop&dpr=1 754w, https://images.theconversation.com/files/417872/original/file-20210825-23-1khh9n5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1309&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/417872/original/file-20210825-23-1khh9n5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1309&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Adult emerald ash borer beetles are about 0.5 inches long (photo not to scale).</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Emerald_ash_borer#/media/File:Agrilus_planipennis_001.jpg">PA DEC</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p><a href="https://biology.richmond.edu/faculty/kgrayson/">I study invasive forest insects</a> and work with the USDA to develop easier ways of raising emerald ash borers and other invasive insects in research laboratories. This work is critical for discovering and testing ways to better manage forest recovery and prevent future outbreaks. But while the emerald ash borer has spread uncontrollably in nature, producing a consistent laboratory supply of these insects is surprisingly challenging – and developing an effective biological control program requires a lot of target insects.</p>
<h2>The value of ash trees</h2>
<p>Researchers believe the emerald ash borer likely arrived in the U.S. on imported wood packaging material from Asia sometime in the 1990s. The insects lay eggs in the bark crevices of ash trees; when larvae hatch, they tunnel through the bark and feed on the inner layer of the tree. Their impact becomes apparent when the bark is peeled back, revealing dramatic feeding tracks. These channels damage the trees’ <a href="https://www.britannica.com/science/vascular-tissue">vascular tissue</a> – internal networks that transport water and nutrients – and ultimately kill the tree. </p>
<p>Before this invasive pest appeared on the scene, ash trees were particularly popular for residential developments, representing 20-40% of planted trees in some Midwestern communities. Emerald ash borers have killed tens of millions of U.S. trees with an estimated replacement cost of US$10-25 billion. </p>
<p>Ash wood is also <a href="http://www.hardwooddistributors.org/postings/ash-lumber-and-the-emerald-ash-borer">popular for lumber</a> used in furniture, sports equipment and paper, among many other products. The ash timber industry produces <a href="https://www.aphis.usda.gov/import_export/plants/manuals/domestic/downloads/eab-manual.pdf">over 100 million board feet annually, valued at over $25 billion</a>. </p>
<h2>Why quarantines have failed</h2>
<p>State and federal agencies have used quarantines to combat the spread of several invasive forest insects, including <a href="https://www.aphis.usda.gov/aphis/resources/pests-diseases/hungry-pests/the-threat/asian-longhorned-beetle/asian-longhorned-beetle">Asian longhorned beetles</a> and <a href="https://www.aphis.usda.gov/aphis/ourfocus/planthealth/plant-pest-and-disease-programs/pests-and-diseases/gypsy-moth/ct_gypsy_moth"><em>Lymantria dispar</em></a>, <a href="https://www.entsoc.org/better-common-names-project">previously known as gypsy moth</a>. This approach seeks to reduce the movement of eggs and young insects hidden in lumber, nursery plants and other wood products. In counties where an invasive species is detected, regulations typically require wood products to be heat-treated, stripped of bark, fumigated or chipped before they can be moved. </p>
<p>The federal emerald ash borer quarantine started with 13 counties in Michigan in 2003 and increased exponentially over time to cover than a quarter of the continental U.S. Quarantines can be effective when forest insect pests mainly spread through movement of their eggs, hitchhiking long distances when humans transport wood. </p>
<p>However, female emerald ash borers <a href="https://www.federalregister.gov/documents/2020/12/15/2020-26734/removal-of-emerald-ash-borer-domestic-quarantine-regulations">can fly up to 12 miles per day for as long as six weeks after mating</a>. The beetles also are difficult to trap, and typically are not detected until they have been present for three to five years – too late for quarantines to work. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/417874/original/file-20210825-23-1ukonjt.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Map showing range of ash trees and counties where emerald ash borer has been detected." src="https://images.theconversation.com/files/417874/original/file-20210825-23-1ukonjt.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/417874/original/file-20210825-23-1ukonjt.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=464&fit=crop&dpr=1 600w, https://images.theconversation.com/files/417874/original/file-20210825-23-1ukonjt.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=464&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/417874/original/file-20210825-23-1ukonjt.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=464&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/417874/original/file-20210825-23-1ukonjt.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=583&fit=crop&dpr=1 754w, https://images.theconversation.com/files/417874/original/file-20210825-23-1ukonjt.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=583&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/417874/original/file-20210825-23-1ukonjt.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=583&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 emerald ash borer has been detected throughout much of the range of ash trees in the U.S.</span>
<span class="attribution"><a class="source" href="https://www.aphis.usda.gov/plant_health/plant_pest_info/emerald_ash_b/downloads/eab-ash-range-map.pdf">USDA</a></span>
</figcaption>
</figure>
<h2>Next option: Wasps</h2>
<p>Any biocontrol plan poses concerns about unintended consequences. One notorious example is the introduction of cane toads in Australia in the 1930s to reduce beetles on sugarcane farms. The toads didn’t eat the beetles, but they spread rapidly and ate lots of other species. And <a href="https://www.environment.gov.au/biodiversity/invasive-species/publications/factsheet-cane-toad-bufo-marinus">their toxins killed predators</a>. </p>
<p>Introducing species for biocontrol is strictly regulated in the U.S. It can take two to 10 years to demonstrate the effectiveness of potential biocontrol agents, and obtaining a permit for field testing can take two more years. Scientists must demonstrate that the released species specializes on the target pest and has minimal impacts on other species.</p>
<p>Four wasp species from China and Russia that are natural enemies of the emerald ash borer have gone through the approval process for field release. These wasps are parasitoids: They deposit their eggs or larvae into or on another insect, which becomes an unsuspecting food source for the growing parasite. Parasitoids are great candidates for biocontrol because they typically exploit a single host species.</p>
<p>The selected wasps are tiny and don’t sting, but their egg-laying organs can penetrate ash tree bark. And they have specialized sensory abilities to find emerald ash borer larva or eggs to serve as their hosts.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/418053/original/file-20210826-23-se9m77.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Ash borer larva and a wasp species that preys on it." src="https://images.theconversation.com/files/418053/original/file-20210826-23-se9m77.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/418053/original/file-20210826-23-se9m77.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=306&fit=crop&dpr=1 600w, https://images.theconversation.com/files/418053/original/file-20210826-23-se9m77.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=306&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/418053/original/file-20210826-23-se9m77.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=306&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/418053/original/file-20210826-23-se9m77.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=385&fit=crop&dpr=1 754w, https://images.theconversation.com/files/418053/original/file-20210826-23-se9m77.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=385&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/418053/original/file-20210826-23-se9m77.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=385&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 emerald ash borer larva in wood (left); <em>Tetrastichus planipennisi</em>, a parasitic wasp that preys on ash borers; and wasp larva that have grown and eaten the ash borer.</span>
<span class="attribution"><span class="source">USDA</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>The USDA is working to rear massive numbers of parasitoid wasps in lab facilities by providing lab-grown emerald ash borers as hosts for their eggs. Despite COVID-19 disruptions, the agency produced over 550,000 parasitoids in 2020 and released them at over 240 sites.</p>
<p>The goal is to create self-sustaining field populations of parasitoids that reduce emerald ash borer populations in nature enough to allow replanted ash trees to grow and thrive. Several studies have shown <a href="https://www.fs.fed.us/nrs/pubs/jrnl/2015/nrs_2015_bauer_001.pdf">encouraging early results</a>, but securing a future for ash trees will require more time and research. </p>
<p>One hurdle is that emerald ash borers grown in the lab need fresh ash logs and leaves to complete their life cycle. I’m part of a team working to develop an alternative to the time- and cost-intensive process of collecting logs: an artificial diet that the beetle larvae can eat in the lab. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/416540/original/file-20210817-15-sq9zae.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/416540/original/file-20210817-15-sq9zae.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/416540/original/file-20210817-15-sq9zae.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/416540/original/file-20210817-15-sq9zae.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/416540/original/file-20210817-15-sq9zae.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/416540/original/file-20210817-15-sq9zae.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/416540/original/file-20210817-15-sq9zae.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/416540/original/file-20210817-15-sq9zae.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">Fresh cut ash logs await processing to collect newly emerging emerald ash borer adults, which will lay eggs for the laboratory colony.</span>
<span class="attribution"><a class="source" href="https://drive.google.com/drive/folders/1gayeW50DEK6sQ6-zahQIRkIMbrhfO3Hi">Anson Eaglin/USDA</a></span>
</figcaption>
</figure>
<p>The food must provide the right texture and nutrition. Other leaf-feeding insects readily eat artificial diets made from wheat germ, but species whose larvae digest wood are pickier. In the wild, emerald ash borers only feed on species of ash tree.</p>
<p>In today’s global economy, with people and products moving rapidly around the world, it can be hard to find effective management options when invasive species become established over a large area. But lessons learned from the emerald ash borer will help researchers mobilize quickly when the next forest pest arrives.</p>
<p><em>This article has been updated to correct the plural form of larva to larvae.</em></p><img src="https://counter.theconversation.com/content/158403/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kristine Grayson receives cooperative agreement funding from the USDA Animal and Plant Health Inspection Service (APHIS) program for Plant Protection and Quarantine (PPQ). </span></em></p>Biological control strategies curb pests using other species that attack the invader. A biologist explains why it can take more than a decade to develop an effective biological control program.Kristine Grayson, Associate Professor of Biology, University of RichmondLicensed as Creative Commons – attribution, no derivatives.