tag:theconversation.com,2011:/africa/topics/zebra-finches-744/articlesZebra finches – The Conversation2023-11-12T14:02:46Ztag:theconversation.com,2011:article/2167992023-11-12T14:02:46Z2023-11-12T14:02:46ZBirds’ nests express their unique style and past experiences<figure><img src="https://images.theconversation.com/files/558442/original/file-20231108-23-ci8gl3.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3303%2C2185&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Zebra finches learn from experience when it comes to building nests.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><iframe style="width: 100%; height: 100px; border: none; position: relative; z-index: 1;" allowtransparency="" allow="clipboard-read; clipboard-write" src="https://narrations.ad-auris.com/widget/the-conversation-canada/birds-nests-express-their-unique-style-and-past-experiences" width="100%" height="400"></iframe>
<p>Walking through a town or city, you will encounter buildings with diverse shapes and sizes. These unique styles exist in part because the buildings were constructed by different architects, engineers and builders. </p>
<p>Birds are also architects, engineers and builders. <a href="https://doi.org/10.1016/j.isci.2023.108194">Our research</a> finds that, similar to human architecture, individual birds build nests in their own unique style. Experienced birds build with more consistent style and use fewer material resources than inexperienced birds. </p>
<h2>Animal architecture</h2>
<p>Architecture impacts our everyday lives, allowing us to adapt to and thrive in various climates. Humans build different structures to achieve different goals: farms to grow and store food, castles and skyscrapers to display wealth, homes for shelter or as a place to raise a family. </p>
<p>The same is <a href="https://doi.org/10.1016/j.cub.2021.09.082">true for other species</a>. Bees build <a href="https://www.archdaily.com/946778/the-incredible-architecture-of-bees">hives and honey combs</a> to store and protect food. Spiders <a href="https://news.mit.edu/2021/considering-the-spiderweb-0810">spin webs</a> to catch prey. Beavers <a href="https://www.nps.gov/articles/buildabeaverdam.htm">build dams</a> to create a pool. Many species of birds <a href="https://doi.org/10.1016/j.cub.2008.01.020">construct nests</a> for shelter or to raise their chicks.</p>
<p>Building architecture allows animals to shape their environments to better meet specific needs.</p>
<h2>Architectural styles</h2>
<p>Human structures look different, even when those structures share a similar purpose. This might reflect differences in culture and available resources.</p>
<p>In western societies, houses tend to be cuboids made from stone, wood and glass. Plains Indigenous Peoples make conical <a href="https://www.ualberta.ca/folio/2018/05/tipi-raised-to-recognize-relationship-between-first-nations-u-of-a.html">tipis from wood and bison hides</a>. Inuit peoples use <a href="https://www.avataq.qc.ca/en/Nunavimmiuts/Puurtaq-Project/Life-in-an-igloo">ice and snow to make spherical igloos</a>. East African Maasai peoples build cylindrical <a href="https://friendsofnamuncha.org/clearing-the-smoke-from-manyattas/">manyatta huts from earth, grass and cow dung</a>.</p>
<p>There are differences in architectural style among individuals within the same culture using the same materials. </p>
<p>Visualize your home: the size and shape of each room, position of doors and windows, arrangement of furniture. Now compare your visualized blueprint to the blueprint of a friend’s house. They likely look quite different, as humans have individual variation in architectural style.</p>
<p>Our research suggests the same is true for animal architects: animals also build structures with <a href="https://doi.org/10.1016/j.isci.2023.108194">individual variation in architectural style</a>. </p>
<h2>Avian architects</h2>
<p>Birds are among the most <a href="https://doi.org/10.1016/j.cub.2022.06.078">well-known builders in the animal world</a>. Many avian species build nests to create safe, warm environments to incubate their eggs and raise chicks. Nest building is a key task that individuals must complete to successfully reproduce. </p>
<p>Our team, the <a href="https://sites.psych.ualberta.ca/animal-cognition-ualberta/">Animal Cognition Research Group</a> in the <a href="https://www.ualberta.ca/psychology/index.html">Department of Psychology</a> at the <a href="https://www.ualberta.ca/index.html">University of Alberta</a>, ran an experiment testing whether birds built nests in their own individual style. </p>
<p>We studied <a href="https://ebird.org/species/zebfin2">zebra finches</a>, small songbirds native to Australia. Zebra finches have been bred in captivity for years and are common in pet stores and <a href="https://doi.org/10.1071/MUv110n3_ED">scientific research</a>. These birds are ideal for our test, as males build many nests in short periods of time using a range of materials.</p>
<p>We measured the sizes and shapes of multiple nests built by the same zebra finches. Comparing nests built by the same male found similarities in style. Comparing nests built by different males found dissimilarities in style. This shows individuals do build nests in their own unique and repeatable style.</p>
<h2>Psychology of style</h2>
<p>The minds of human architects can be studied through analyzing the style in which they build. This gives insights on their understanding of technology and their cultural influences or social values.</p>
<p>Some ancient structures, like <a href="https://doi.org/10.1088/1742-6596/685/1/012001">the pyramids of Giza, Stonehenge and Mayan structures</a>, are aligned to the sun and stars. This demonstrates ancient architects had the ability to precisely plan and execute designs with great detail. It also suggests that celestial bodies held some significance to these cultures, perhaps for mapping landscapes or the passage of seasons. </p>
<p>An individual architect might specialize in building structures of a particular style, such as <a href="https://www.archdaily.com/983605/the-origins-and-evolution-of-gothic-architecture">Gothic</a>, <a href="https://www.archdaily.com/972018/what-is-art-deco-architecture">Art Deco</a>, <a href="https://www.archdaily.com/774100/should-victorian-era-architecture-be-saved-at-all-costs">Victorian</a> or <a href="https://www.archdaily.com/957201/brutalism-the-architecture-style-we-love-to-love">Brutalist</a>. Their style might change over time as the architect learns and refines their skills through experience. </p>
<p>These examples show how the psychology of style can be analyzed in human architects. We wanted to investigate the psychology of style, specifically learning from experience, in our zebra finches.</p>
<h2>Style and experience</h2>
<p>We gave one group of zebra finches practise building five nests, giving each male opportunities to learn from this nest-building experience. A second group of zebra finches had no practise building. These males had never built a nest before the start of the experiment. Both groups then built nests so that we could compare the nest style built by the two groups.</p>
<p>Experienced birds had more consistent nest style and used less material compared to inexperienced birds. This indicates that learning opportunities influence nest style. </p>
<p>Practice building nests allows birds to <a href="https://doi.org/10.1016/j.beproc.2011.06.011">develop motor skills</a> and better manipulate materials. Birds also <a href="https://doi.org/10.1016/j.beproc.2021.104336">remember past outcomes</a> of nests and will replicate successful design elements. </p>
<p>Individual style might develop from differences in learning opportunities. Maintaining a style might even be beneficial. Creating consistent nests while using fewer resources may be advantageous, especially if the style has been successful or resources are limited.</p>
<p>We can learn a lot about how both human and animal architects adapt and respond to their surroundings and culture by studying the structures they build. Our research also shows home isn’t just where the heart is … it’s also in the brain.</p><img src="https://counter.theconversation.com/content/216799/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Birds’ nest-building skills are informed by their environment and experiences, and nests can reflect the individual styles of their builders.Ben Whittaker, Postdoctoral Researcher, Department of Psychology, University of AlbertaLauren Guillette, Assistant Professor & Canada Research Chair in Cognitive Ecology, Department of Psychology, University of Alberta, University of AlbertaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/474962015-09-16T13:46:58Z2015-09-16T13:46:58ZHolding out for ‘the one’ makes evolutionary sense, suggests lovebirds study<figure><img src="https://images.theconversation.com/files/95049/original/image-20150916-6281-1lhr6pl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">No, I said I love YOU more.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/sunphlo/9521173315/">sunphlo/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span></figcaption></figure><p>Most of us have spent a considerable part of our life looking for true love – our perfect match. The search for an ideal partner isn’t exclusive to humans, many animals do it too. But from an evolutionary perspective it is not actually clear why we couple up at all. Why spend time and effort on being fuzzy when we could be reproducing?</p>
<p>Now a new study in birds has shed some light on this long-standing problem, suggesting there are actually <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1002248">evolutionary benefits</a> from finding the ideal mate. The findings may apply to humans, too.</p>
<h2>It’s complicated</h2>
<p>So how do you know who your perfect partner is? The answer seem to change from species to species. Because females usually <a href="http://www.jstor.org/stable/2462085?seq=1#page_scan_tab_contents">invest more</a> in reproduction than males, they tend to be the choosier sex. Often, there is broad agreement on which <a href="http://www.pnas.org/content/103/44/16343.full">males are the most desirable</a>. These males either provide superior resources, such as really good territory, or superior genes that guarantee healthier offspring. </p>
<p>In humans too, there are some individuals who are generally agreed upon <a href="http://legacy.jyi.org/volumes/volume6/issue6/features/feng.html">to be extremely attractive</a>. This kind of agreement, however, is not necessarily a big factor when it comes to choosing a long-term partner. In fact when it comes to finding “the one”, the right mate seems to differ from person to person.</p>
<p>Although humans are quite rare among mammals in maintaining long-term (or even life-long) relationships, they share this trait with many bird species. One such species is the zebra finch, a common bird often used in research. Like people, zebra finches <a href="http://phys.org/news/2012-01-monogamous-birds-neighbors.html">pair up for the long term</a>, and each bird has its own preference. </p>
<p>The new study, published in the journal PLoS Biology, investigated why this might be. The researchers reasoned that if animals put so much effort into finding the perfect partner, then there must be a benefit of reproducing with that partner rather than another one, or many other ones. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/95002/original/image-20150916-12004-b6muer.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/95002/original/image-20150916-12004-b6muer.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=614&fit=crop&dpr=1 600w, https://images.theconversation.com/files/95002/original/image-20150916-12004-b6muer.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=614&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/95002/original/image-20150916-12004-b6muer.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=614&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/95002/original/image-20150916-12004-b6muer.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=771&fit=crop&dpr=1 754w, https://images.theconversation.com/files/95002/original/image-20150916-12004-b6muer.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=771&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/95002/original/image-20150916-12004-b6muer.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=771&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Lovebirds.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/maryshattock/14724734439/in/photolist-orb7xH-rvrfos-qyxnxC-qyxkeu-rvrd4s-oAy4Tz-oAzh3H-cDUDrY-oAyB2C-oAyoDG-oR1Zgj-oT3e8H-oAyBYM-oAxNnL-oT2ke9-oT1sPS-oT3GSv-oSMpa2-oAygD1-oAyAjV-oAxNT7-oT4kLR-oAy1yQ-oSM2kR-oSLLmn-oT4iLi-saHj7d-oAywr7-oAxvJY-oAzdyZ-rg15Z3-oAyMqc-oT39ag-6nvGtL-pegrda-oT34L6-oT1gM1-oR1nKu-gNutCZ-6pWhcu-6oAMPa-qvujty-r3iiR-6v3KJS-t5JFTJ-nawXrK-sT7Mb-sT7S5-6tH2tA-et9Fg1">m.shattock/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>To find out, they let 160 birds pick their own partners in a large communal enclosure. After the birds had paired up, they were put in smaller cages for two months. Half of the couples were housed with their own chosen partner, while the other half was housed with someone else’s choice of partner. </p>
<p>By using birds that had previously been chosen by another bird, they controlled for the possible confound of partnering up birds with “objectively” inferior mates. Still, applying Stephen Stills’ “<a href="http://www.metrolyrics.com/love-the-one-youre-with-lyrics-stephen-stills.html">Love the one you’re with</a>” principle, these birds eventually formed pair bonds as well. Finally, all of the now-established pairs were put into larger aviaries again (six pairs in each cage) to reproduce.</p>
<p>The outcome was dramatic. Birds that reproduced with their own choice of partner had 37% more chicks that survived to adulthood than birds that mated with a partner not of their choice. This showed that some form of partner compatibility is important for these birds’ reproductive success. </p>
<h2>Domestic harmony</h2>
<p>But why were the “forced” pairs less successful at reproduction? There are two possibilities. One is that the partners were genetically less compatible. In humans, being genetically similar may mean a good match (though it has also been reported that humans are more <a href="http://www.eoht.info/page/Sweaty+T-shirt+study">attracted to the smell of sweaty t-shirts</a> worn by people who have genetically different <a href="http://www.geneticliteracyproject.org/2014/05/20/genes-matter-people-marry-mates-with-similar-dna-but-different-immune-systems/">immune systems</a>). </p>
<p>The other possibility is that the partners were less compatible behaviourally (for example in their temperaments).</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/95015/original/image-20150916-12018-db4aer.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/95015/original/image-20150916-12018-db4aer.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=437&fit=crop&dpr=1 600w, https://images.theconversation.com/files/95015/original/image-20150916-12018-db4aer.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=437&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/95015/original/image-20150916-12018-db4aer.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=437&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/95015/original/image-20150916-12018-db4aer.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=549&fit=crop&dpr=1 754w, https://images.theconversation.com/files/95015/original/image-20150916-12018-db4aer.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=549&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/95015/original/image-20150916-12018-db4aer.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=549&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Believe it or not, birds may be able to tell us something about the importance of finding the one.</span>
<span class="attribution"><span class="source">Pedro Ribeiro Simões/Flickr</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>And the authors of the study had previously shown that <a href="http://beheco.oxfordjournals.org/content/24/1/119">embryo viability</a> of zebra finches is down to the genetic make-up of the embryo and therefore the genetic compatibility of the biological parents, while survival after hatching was purely due to <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3883492/">parental care</a>. </p>
<p>Again, their results in the new study were clear: whereas embryo viability did not differ between the two groups, more young died after hatching in the “forced” group. They were even able to show that “forced” pairs were less lovey-dovey with each other – females in the “forced” group were less attentive to their mate’s courtship, while the males spent less time at the nest and more time courting other females than in pairs who chose their own partners.</p>
<p>But can zebra finches tell us anything about the evolution of mate choice in our own species? Well, despite the similarities, we are not zebra finches. Human mating systems vary across cultures and time. Nevertheless, we have evolved emotions like “attraction” and “love”, which serve the function of finding and pair bonding with a particular individual.</p>
<p>And, just like the zebra finches, different people are attracted to, and compatible with, different partners. It is therefore likely that our own mate choice behaviours, including “dating” and “breaking up”, are part of an evolved strategy to find a compatible partner, who would (at least in evolutionary history) improve our reproductive success. So if you haven’t found “the one” yet, don’t despair. Evolutionary biology suggests it’s worth the time and effort spent searching.</p><img src="https://counter.theconversation.com/content/47496/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tom Smulders 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>Humans as well as zebra finches go through hurdles to find their perfect partner – and this may better ensure the survival of any offspring.Tom Smulders, Senior Lecturer, Centre for Behaviour and Evolution, Newcastle UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/346112014-11-28T16:28:15Z2014-11-28T16:28:15ZBad parenting could give zebra finches the evolutionary edge<figure><img src="https://images.theconversation.com/files/65450/original/image-20141125-2383-173h9mg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Zebra finches may have the potential to become brood parasites</span> <span class="attribution"><a class="source" href="http://en.wikipedia.org/wiki/Zebra_finch#mediaviewer/File:Taeniopygia_guttata_-Bird_Kingdom,_Niagara_Falls,_Ontario,_Canada_-pair-8a.jpg">Keith Gerstung</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>Species must reproduce to survive, and animals have found unique ways of achieving this. For some, including us, it seems as though producing a few offspring that require extended care is the best strategy. For others, such as many coral reef fishes, many offspring that require little care appears better suited.</p>
<p>Brood parasitism is among the most bizarre breeding strategies in nature. A brood parasite, such as a cuckoo, manipulates another individual into raising its young. Hosts do <a href="https://theconversation.com/how-birds-cooperate-to-defeat-cuckoos-21556">all they can</a> to stop brood parasites from successfully reproducing, because they usually harm their own young. Brood parasites <a href="https://theconversation.com/egg-colours-make-cuckoos-masters-of-disguise-34217">fight back</a>, and the two species can become locked in a coevolutionary arms race. </p>
<p>Despite these troubles, not having to build a nest, incubate eggs or care for offspring allows brood parasites to produce more eggs than they would otherwise. This can make brood parasitism viable through evolutionary time.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/65453/original/image-20141125-2362-1lxp2sy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/65453/original/image-20141125-2362-1lxp2sy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=357&fit=crop&dpr=1 600w, https://images.theconversation.com/files/65453/original/image-20141125-2362-1lxp2sy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=357&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/65453/original/image-20141125-2362-1lxp2sy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=357&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/65453/original/image-20141125-2362-1lxp2sy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=449&fit=crop&dpr=1 754w, https://images.theconversation.com/files/65453/original/image-20141125-2362-1lxp2sy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=449&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/65453/original/image-20141125-2362-1lxp2sy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=449&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A zebra finch getting ready to line its nest.</span>
<span class="attribution"><span class="source">Gil Dekel</span></span>
</figcaption>
</figure>
<p>But how can this bizarre breeding strategy evolve? </p>
<p>Consider this example: if a bird lays its eggs over several days, but its nest gets destroyed before it completes its clutch, it could salvage the remaining eggs by laying them in the nests of birds from other species. If the offspring was successfully raised by the unsuspecting host, this unexpected brood parasitism event may provide a stepping stone this behaviour to evolve further. </p>
<p>In a study published today in <a href="http://onlinelibrary.wiley.com/doi/10.1002/ece3.1243/abstract?campaign=wolearlyview">Ecology and Evolution</a>, we experimentally investigated this idea using captive zebra finches. These finches are well studied and commonly used in behavioural experiments. </p>
<p>We conducted experiments on 17 pairs of zebra finches. Each experimental aviary contained three identical nests as well as nesting material. When the birds chose a nest and laid their first egg, a zebra finch egg was added to one of the additional nests, and a Bengalese finch egg was added to the other. Bengalese finches are a closely related to zebra finches, and lay eggs that are larger and sometimes different in colour to zebra finch eggs.</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/65452/original/image-20141125-2371-15hdhxj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/65452/original/image-20141125-2371-15hdhxj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=820&fit=crop&dpr=1 600w, https://images.theconversation.com/files/65452/original/image-20141125-2371-15hdhxj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=820&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/65452/original/image-20141125-2371-15hdhxj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=820&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/65452/original/image-20141125-2371-15hdhxj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1030&fit=crop&dpr=1 754w, https://images.theconversation.com/files/65452/original/image-20141125-2371-15hdhxj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1030&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/65452/original/image-20141125-2371-15hdhxj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1030&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A) a small zebra finch egg next to a Bengalese finch egg, B) the number of zebra finches that laid in nest containing either a zebra finch or Bengalese finch egg.</span>
<span class="attribution"><span class="source">Ecology and Evolution (John Wiley and Sons)</span></span>
</figcaption>
</figure>
<p>The active zebra finch nest was then removed from the experimental aviary. The finch was left with the choice of laying its next egg either in a nest containing a zebra finch egg, a nest containing a Bengalese finch egg, or somewhere else in the aviary. If the eggs were not preferentially laid in nests containing other zebra finch eggs, it may suggest that they either do not use cues from the eggs in the nest to make a decision where to lay their own egg, or that they show no preference for what nest their egg is laid in following destruction of their own nest.</p>
<p>We found that there was no significant difference between where the next egg was laid. Ten of the zebra finches laid their next egg in the nest containing a Bengalese finch egg and seven laid in the nest containing another zebra finch egg. This is the first experiment to suggest that an unexpected change in conditions – in this case, nest destruction during egg laying – may provide an evolutionary pathway to brood parasitism in birds.</p>
<p>These are the kinds of biological leaps that Darwin discovered when he first studied finches. And, even today, we are still learning.</p><img src="https://counter.theconversation.com/content/34611/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>William Feeney receives funding from Australian Geographic and the Australian National University.</span></em></p>Species must reproduce to survive, and animals have found unique ways of achieving this. For some, including us, it seems as though producing a few offspring that require extended care is the best strategy…William Feeney, PhD student, Australian National UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/115202013-01-10T19:26:37Z2013-01-10T19:26:37ZBirds and boasting: honest when mating, dishonest when dating<figure><img src="https://images.theconversation.com/files/19107/original/9ky9n3nn-1357780942.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A female zebra finch finds herself surrounded by male suitors - but who to listen to?</span> <span class="attribution"><span class="source">Simon Griffith</span></span></figcaption></figure><p>A <a href="http://www.ncbi.nlm.nih.gov/pubmed/23256191">new study</a> has revealed what many people possibly already suspect – males are more honest when displaying their “quality” to a partner than to an unfamiliar female.</p>
<p>These findings, from a study of a socially monogamous bird, are likely to apply to any animal that forms long-term partnerships, including humans. </p>
<p>What do we mean by “quality” here? Well, in evolutionary terms, “quality” refers to the variation in an individual’s health, strength, size, and ability to provide resources.</p>
<p>In socially monogamous animals it makes sense for females to try and identify all the qualities of a male that will help her to produce lots of offspring. Males often hold territories, and provide food to the offspring, as well as providing sperm that help to create the offspring in the first place.</p>
<h2>The long haul</h2>
<p>Because of the prolonged association between partners, it is very difficult for a male to keep deceiving a partner about his quality in the long term. Why? It’s all about the cost.</p>
<p>In birds, singing is costly to males in terms of:</p>
<ul>
<li>the energy required to produce song</li>
<li>the time invested in singing at the expense of other activities (such as foraging), and</li>
<li>the cost of exposing oneself to predators.</li>
</ul>
<p>As a result, only males in good condition can maintain high levels of singing for an extended period. </p>
<p>When initially encountering an unknown female for the first time, it makes sense for all males to “display” at a similarly high rate, in an attempt to attract a female’s attention and make a good first impression.</p>
<p>For displays that are energetically expensive, such as singing, even lower-quality males are able to perform at a similar level to their rivals for that important but short first encounter. After a short period, lower-quality males are unable to sustain the effort, but if the female has already moved on it doesn’t matter.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/19115/original/dfsdnzgb-1357793185.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/19115/original/dfsdnzgb-1357793185.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=424&fit=crop&dpr=1 600w, https://images.theconversation.com/files/19115/original/dfsdnzgb-1357793185.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=424&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/19115/original/dfsdnzgb-1357793185.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=424&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/19115/original/dfsdnzgb-1357793185.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=533&fit=crop&dpr=1 754w, https://images.theconversation.com/files/19115/original/dfsdnzgb-1357793185.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=533&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/19115/original/dfsdnzgb-1357793185.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=533&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
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<span class="attribution"><span class="source">bartolomeo/Flickr</span></span>
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</figure>
<h2>Speed-dating</h2>
<p>In their new study, Morgan David and colleagues at the University of Bergundy in France placed male <a href="http://en.wikipedia.org/wiki/Zebra_Finch">zebra finches</a> in a cage with an unknown female for either five minutes or one hour. The researchers found that all males took the opportunity to court the female with their song.</p>
<p>In these “speed-dating” trials, the amount of song produced by different males was unrelated to the underlying quality of those males.</p>
<p>(In this study quality was measured by looking at individual body mass. High quality birds typically carry a little more weight than those in lower condition, and this measure of condition is a great predictor of long-term survival and how many offspring a male produces over its life.)</p>
<p>By contrast, when the researchers examined song rates in males that had already established partnerships, and that were singing to a “steady” female partner, they found that call rate was a very reliable predictor of underlying quality.</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/19117/original/2mj6n8wf-1357793359.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/19117/original/2mj6n8wf-1357793359.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=1012&fit=crop&dpr=1 600w, https://images.theconversation.com/files/19117/original/2mj6n8wf-1357793359.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=1012&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/19117/original/2mj6n8wf-1357793359.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=1012&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/19117/original/2mj6n8wf-1357793359.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1272&fit=crop&dpr=1 754w, https://images.theconversation.com/files/19117/original/2mj6n8wf-1357793359.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1272&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/19117/original/2mj6n8wf-1357793359.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1272&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
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<span class="attribution"><span class="source">Peripitus/Wikimedia Commons</span></span>
</figcaption>
</figure>
<p>That is, only males in the best condition produced song at a high rate.</p>
<p>This is probably because males of lower quality were unable to sustain this costly activity for as long, or may have depleted their reserves more quickly and had to break off from their displaying to feed, or rest and recover.</p>
<h2>The long game</h2>
<p>In the short-term, low quality males can potentially bluff and perhaps dig deeper into their reserves. But when there is a true cost to a signal, it is increasingly difficult to maintain such bluff over the long-term, and it might cause long-term damage (if the male chooses singing over foraging, for example).</p>
<p>A good reason for the honesty with which an individual signals its quality to a partner is the nature of the partnership itself. Given partnerships are ultimately about reproduction (in animals at least), socially monogamous partners have a shared interest in being honest with one another about their quality.</p>
<p>It makes sense for a male to signal to his partner about his condition and qualities, because that information is useful to a female in deciding when, and how many offspring to produce. As mentioned above, it may be detrimental to a male to falsely signal his quality to his partner.</p>
<p>If the female tailors her reproduction to his signal, and the number of young she believes he is capable of feeding, then they may end up with too many offspring, none of which will get enough food to ensure healthy development. The male and the female will therefore both lose out in the long-run.</p>
<figure>
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</figure>
<h2>Not just birds</h2>
<p>While this study was conducted on small birds native to the harsh conditions of the Australian outback, there are <a href="https://theconversation.com/australias-first-supermodel-no-not-that-one-2469">lessons about ourselves</a> that can be taken from such studies.</p>
<p>An individual’s evolutionary interests change over time and vary with their status in the mating game. Single, young-blooded males are prone to displays of wealth, status and prowess, the reliability of which is not necessarily easy for a potential partner to assess. Having one good suit or hiring a Porsche for the weekend are good examples of ways individuals can create a false impression of status.</p>
<p>But having a wardrobe full of Italian suits and owning a Porsche outright is more difficult to achieve, and it’s a more honest signal of underlying wealth. </p>
<p>The obvious implication here is to be wary of first impressions – they can be deceptive. The secret to getting an honest appraisal of an individual is through long-term acquaintance. In that sense, a second date is probably far more useful than the first date!</p>
<p>The stronger a bond becomes between a couple and the more intimate they become the better they know and understand the quality and current condition of their partner.</p>
<p>This makes sense because, they are now working as a team and looking out for each other and trying to plan for the future accordingly.</p>
<p>Decisions about where to live, when and if and how many children to have are all very important and are best optimised with a good understanding of each other’s position. </p>
<p>The nice thing about this recent work is that it demonstrates the complexity with which animal signals are used and abused. As well as listening to the song, we need to also consider who is singing, and what his agenda is likely to be.</p><img src="https://counter.theconversation.com/content/11520/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Simon Griffith receives funding from the Australian Research Council.</span></em></p>A new study has revealed what many people possibly already suspect – males are more honest when displaying their “quality” to a partner than to an unfamiliar female. These findings, from a study of a socially…Simon Griffith, Associate Professor of Avian Behavioural Ecology, Macquarie UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/24692011-07-26T21:05:32Z2011-07-26T21:05:32ZAustralia’s first supermodel … no, not that one<figure><img src="https://images.theconversation.com/files/2439/original/aapone-20070412000033127901-elle_macpherson_intimates_launch_sydney-original.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Could the zebra finch's growing popularity ruffle The Body's feathers?</span> <span class="attribution"><span class="source">Tracey Nearmy/AAPIMAGE</span></span></figcaption></figure><p>Long before Elle Macpherson staked her claim to the title, indeed by the end of the 1890s, Australia had inadvertently exported a model to the northern hemisphere that has become internationally famous, the focus of multi-million dollar projects, and the subject of hundreds of articles. </p>
<p>As with some of the more recent antipodean stars such as Kylie, this model is well-known, in the right circles, for its singing <em>and</em> appearance.</p>
<p>Introducing the Zebra finch, <em>Taeniopygia guttata</em>, a bird familiar to many as a childhood pet. </p>
<p>Over the past few decades, this little Aussie has become one of the most important model systems in modern biology and is now the most studied bird in the world. </p>
<p>The crowning glory for this 10-gram finch was that it became just the second bird for which the entire genome was <a href="http://www.nature.com/nature/journal/v464/n7289/full/nature08819.html?guid=ON">sequenced</a>, following work by a 20-institution team in the US and Europe and funded by government research funds in those countries. </p>
<p>That <a href="http://neurolex.org/wiki/Category:Resource:ZEBrA:_A_Zebra_Finch_Brain_Expression_Atlas">publicly accessible</a> genome now provides a very rich resource for understanding how a bird’s genes are arranged and control every aspect of its development, morphology and behaviour. </p>
<p>Most of that work lies in the future and the sequenced genome of the zebra finch provides a framework that will ensure this Australian species plays a central role in the next generation of biological research.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/2443/original/zebmale.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/2443/original/zebmale.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=638&fit=crop&dpr=1 600w, https://images.theconversation.com/files/2443/original/zebmale.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=638&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/2443/original/zebmale.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=638&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/2443/original/zebmale.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=802&fit=crop&dpr=1 754w, https://images.theconversation.com/files/2443/original/zebmale.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=802&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/2443/original/zebmale.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=802&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
<span class="attribution"><span class="source">Simon Griffith</span></span>
</figcaption>
</figure>
<p>In the past half-century, modern biology has developed and utilised a number of famous “animal models” such as the fruit fly, <em>Drosophila melanogaster</em>, a roundworm <em>Caenorhabditis elegans</em>, the zebra fish <em>Danio rerio</em> and the laboratory mouse <em>Mus musculus</em>. </p>
<p>The benefits of concentrating research effort on a few species is considerable. Every new incremental finding can be better interpreted and placed in context against the huge background of other detailed information about that particular organism. </p>
<p>That, in turn, helps develop a deep understanding of animal evolution, genetics, development, physiology and behaviour. </p>
<p>Logistically, it’s also far easier to work on a species for which generations of earlier workers have perfected methods of holding, breeding and raising in captivity, and that, to a large degree, have adapted to laboratory conditions. </p>
<p>While most of the research conducted on these animal models may seem quite arcane to most people, such model systems have a profound effect on our ability to understand biological systems at a fundamental level, contributing to diverse fields such as medicine, cognitive science, and the effort to conserve biodiversity.</p>
<p>The zebra finch has become a particularly important model in the study of neuroscience, and specifically how a brain can support the higher mental processes of language development. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/vM7VTSy1ZX8?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<h2>Dreams from my father</h2>
<p>The song of the male zebra finch (see above) is learned from his father during adolescence by listening and copying in a process that reflects the acquisition of language in a human infant, as they progress from babbling to the formation of words. </p>
<p>It is hoped that eventually work currently being done by research teams in the US will identify genes that will in turn lead to treatments for speech disabilities related to autism and strokes. </p>
<p>The animal models that are used today are selected because they are easy to work with and represent different elements of the tree of life. </p>
<p>The zebra finch is a great model system as a product of the landscape in which it evolved over millions of years – the Australian outback: one of the toughest and most unpredictable environments in the world. </p>
<p>The zebra finch has evolved to overcome the challenge of this environment by ranging around the desert in small social groups. When good conditions are found in this land of boom and bust individuals rapidly nest and produce youngsters. </p>
<p>Remarkably they will breed at any time of the year and for as long as the conditions allow, before the desert dries out once again and the opportunity is lost. </p>
<p>They have the fastest developmental rate of any bird, with the young able to fly within two weeks of hatching, becoming sexually mature and breeding at just over two months of age.</p>
<p>All of these characteristics have made them the perfect bird to study in the laboratory, particularly for evolutionary studies where it is quite possible to work on several generations in the space of a short-term research grant. </p>
<p>Being socially monogamous and having life-long pair bonds, the social and mating system of the zebra finch is actually far more similar to ours than any of the mammals on which behavioural research is typically conducted, none of which are socially monogamous. </p>
<p>The zebra finch also provides an excellent opportunity to investigate, through experiments and cross-generational studies, the evolutionary dynamics of gender roles and strategies in a social system that fundamentally is very similar to our own.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/2446/original/zebfence.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/2446/original/zebfence.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/2446/original/zebfence.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/2446/original/zebfence.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/2446/original/zebfence.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1131&fit=crop&dpr=1 754w, https://images.theconversation.com/files/2446/original/zebfence.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1131&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/2446/original/zebfence.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1131&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
<span class="attribution"><span class="source">Simon Griffith</span></span>
</figcaption>
</figure>
<h2>Bird brain</h2>
<p>If the questions addressed are appropriate and taken in the right context, it is reasonable to learn about ourselves from a bird because evolution is a fundamental process and the mechanisms through which <a href="http://theconversation.com/explainer-theory-of-evolution-2276">Darwinian selection</a> will act apply equally to modern humans as to a bird in the desert or the laboratory. </p>
<p>The zebra finch has been used to experimentally examine the dynamics of conflict between male and female partners over the level of investment in their offspring. </p>
<p>That conflict exists because each individual has the potential to increase its own fitness at the expense of its partner by investing in <a href="http://theconversation.com/all-about-the-girl-the-mating-game-and-how-not-to-win-it-527">alternative strategies</a>.</p>
<p>These alternatives differ between males and females in similar ways across sexually reproducing animals. </p>
<p>In organisms with internal fertilisation and social pair bonds, female behaviour and investment in offspring is underscored by a confidence that the offspring are genetically hers. </p>
<p>Males can never be as confident because it is possible that <a href="http://theconversation.com/one-flew-over-the-cuckolds-nest-a-birds-eye-view-of-female-infidelity-1909">other males may have copulated with their female partner</a>, and this results in a different set of selective pressures on male behaviour and investment. </p>
<p>The specifics of parental care in zebra finches and humans are obviously very different but the fundamentals guiding selection on male and female investment strategies are similar. </p>
<p>The evolutionary dynamics can be demonstrated through experimental manipulation in a bird model in a way that is not ethically or logistically possible in a human. </p>
<p>Preventing a male bird from seeing his partner for a few hours during her fertile period may subsequently change the effort he makes in parental care weeks later.</p>
<p>The guiding principle when deciding when it would be appropriate to extrapolate from one animal to another (humans included) is whether there is a common fundamental biological process in play. </p>
<p>As such, the zebra finch is more comparable to all other birds than it is to humans, and intensive studies of this model in the laboratory have provided important insight into many areas of avian biology. </p>
<p>Ultimately, by understanding how birds work through detailed studies of common and abundant birds such as the zebra finch, we will be better placed to manage and conserve those birds that are at a higher risk of extinction. </p>
<p>So next time you hear the distinctive “meep meep” of a $5 zebra finch in a pet shop, don’t underestimate what this iconic species can tell us about the ourselves and the biological systems that are so important to the future health of the planet. </p>
<p>As for Elle Macpherson … she’s done not too badly at all.</p><img src="https://counter.theconversation.com/content/2469/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Simon Griffith receives funding from the Australian Research Council.</span></em></p>Long before Elle Macpherson staked her claim to the title, indeed by the end of the 1890s, Australia had inadvertently exported a model to the northern hemisphere that has become internationally famous…Simon Griffith, Associate Professor of Avian Behavioural Ecology, Macquarie UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/19092011-06-27T04:19:17Z2011-06-27T04:19:17ZOne flew over the cuckold’s nest: a birds-eye view of female infidelity<figure><img src="https://images.theconversation.com/files/1885/original/zebpairsaltbushsmall.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Wild zebra finch pairs keep their eyes peeled for opportunities to cheat.</span> <span class="attribution"><span class="source">Simon Griffith</span></span></figcaption></figure><p>Infidelity between sexual partners is ubiquitous – almost as prevalent as the tight and long-lasting social bonds that couples form. </p>
<p>But thanks to <a href="http://sn-web01.sciencenews.org/view/generic/id/331272/title/Female_infidelity_may_violate_goose-gander_parity_principle">a recent German study of Australian zebra finches</a>, a cheating partner now has a new excuse: they can blame both their male and female ancestors. </p>
<p>It now seems that the genes driving promiscuous behaviour have a long history of being shaped by evolutionary selection in both males and females. </p>
<p>The costs of infidelity can be high, with both males and females likely to desert an unfaithful partner, or at least reduce their investment into the partnership and any resulting offspring. Despite the risks, both males and females regularly cheat on each other. </p>
<p>The evolutionary forces underlying such behaviour have been the focus of research over the past three decades. The potential reward for a male that cheats on his partner is the opportunity to sire additional offspring with another female, without having to invest any parental effort into those offspring. </p>
<p>Throughout the ages, it is well known that high-status males such as kings, politicians and more recently <a href="http://theconversation.com/get-laid-or-die-trying-how-rock-stars-get-their-kicks-in-1784">rock stars</a> have produced many offspring outside the marital bed (but of course such behaviour is more widespread). </p>
<p>The difference in the number of offspring sired by such men, compared to those who remain faithful to their partner, is a very powerful evolutionary force – first described by Darwin in 1871 as <a href="http://en.wikipedia.org/wiki/Sexual_selection">“sexual selection”</a>.</p>
<p>Successful cheats will, on average, leave more descendants (and therefore genes) in following generations than those males who remain faithful. Cheats will probably also produce children with their own partner and be less likely to be cuckolded themselves. </p>
<p>A male that is attractive enough to succeed in gaining extra-pair copulations with other females is likely to be highly valued by his own partner and she is unlikely to cheat on him. </p>
<h2>Be still my cheating heart</h2>
<p>In contrast to the male side of the story, the benefits of infidelity are not as obvious for females. An unfaithful female is unlikely to increase the number of offspring that she produces, and she will still have to invest as heavily in offspring sired by an extra-pair male. </p>
<p>The costs of desertion by a partner who suspects he has been cuckolded are also probably higher to a female because she is likely to have to bear the full cost of rearing offspring on her own. </p>
<p>Females typically receive nothing from extra-pair males other than sperm, so it has been suggested that the main benefit to a female from an extra-pair coupling is to gain good genes from that male for some of her offspring. </p>
<p>But despite much work, there has been very little evidence that the extra-pair offspring are better than within-pair offspring. There are already some theories as to why females are as likely as males to engage in risky extra-pair behaviour (and they typically are because “it takes two to tango”).</p>
<p>Wolfgang Forstmeier and his colleagues in Germany have added an exciting new angle to the debate by showing that there is a genetic correlation between promiscuous behaviour in males and females. Their findings suggest that some of the same genes drive cheating behaviour in males and females. </p>
<p>Strong selection on the behaviour in one sex will see the behaviour being expressed in the other sex simply as a by-product of the fact that all of us carry genes from both our mother and father. </p>
<p>A gene that makes a male particularly successful is likely to be passed on to his daughters as well as his sons.</p>
<h2>Tweet to woo</h2>
<p>In the study, Dr Forstmeier and his team analysed thousands of hours of video footage of male Australian zebra finches (<em>Taeniopygia guttata</em>) courting females. The team were interested in whether the males’ advances were rejected or accepted by the female, often resulting in a successful copulation. </p>
<p>The team were able to demonstrate the key “genetic correlation” in the propensity to engage in extra-pair behaviour. </p>
<p>They did so by studying more than 1,500 individuals over five consecutive generations and tracking the behavioural similarities between male and female relatives in a large pedigree. </p>
<p>This excellent and highly detailed study tells us how evolution works in sexually reproducing animals. It shows us that the genetics underlying behavioural traits are often very complex, and our ability to study the Darwinian selection of such traits is difficult. </p>
<p>While males and females are very different in both structure and behaviour, many of the genes that determine male characters will also be carried by females (and vice versa). </p>
<p>This means that as genes move across generations and spend time in either male or female individuals, natural selection will often be trying to pull them in different directions. </p>
<p>In their study, Forstmeier and colleagues show that the genes that help to determine promiscuity in males and increase their success in producing descendants, are quite costly when carried by females. </p>
<p>As a result many females in the population are participating in behaviour that makes little sense for them but may ultimately improve the success of their male descendants.</p>
<p>This study provides a fundamental understanding about how evolution and genetics shape sexual behaviour in socially monogamous animals. The study is of great relevance to humans and any other animals that form long-term pair bonds for reproductive purposes.</p>
<p><strong>_Why do you think people cheat on their partners? Is “it’s only evolution, darling,” an acceptable excuse? Leave your views below. _</strong></p><img src="https://counter.theconversation.com/content/1909/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Simon Griffith receives funding from the Australian Research Council.</span></em></p>Infidelity between sexual partners is ubiquitous – almost as prevalent as the tight and long-lasting social bonds that couples form. But thanks to a recent German study of Australian zebra finches, a cheating…Simon Griffith, Associate Professor of Avian Behavioural Ecology, Macquarie UniversityLicensed as Creative Commons – attribution, no derivatives.