tag:theconversation.com,2011:/fr/topics/domestication-7095/articlesDomestication – The Conversation2024-02-11T19:04:45Ztag:theconversation.com,2011:article/2225142024-02-11T19:04:45Z2024-02-11T19:04:45ZPermaculture showed us how to farm the land more gently. Can we do the same as we farm the sea?<figure><img src="https://images.theconversation.com/files/574289/original/file-20240208-28-ugs4w9.jpg?ixlib=rb-1.1.0&rect=1166%2C32%2C3789%2C2076&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>As wild fish and other marine species get scarcer from overfishing and demand for ‘<a href="https://www.sciencedirect.com/science/article/pii/S2211912422000281">blue foods</a>’ grows around the world, farming of the ocean is growing rapidly. Fish, kelp, prawns, oysters and more are now widely farmed. The world now <a href="https://ourworldindata.org/rise-of-aquaculture">eats more farmed seafood</a> than wild-caught. </p>
<p>These farms are springing up along coasts and in offshore waters worldwide. Australians will be familiar with Tasmania’s salmon industry, New South Wales’ oyster farms, and <a href="https://www.frdc.com.au/seaweed-aquaculture-australia#:%7E:text=Asparagopsis%20aquaculture&text=The%20commercial%20seaweed%20farming%20industry,South%20Australia%2C%20and%20Western%20Australia.">seaweed farms</a> along the southern coastline. Aquaculture is already <a href="https://www.theguardian.com/australia-news/2023/mar/18/if-we-want-to-eat-it-we-have-to-farm-it-the-push-to-grow-australias-2bn-aquaculture-industry">larger than fishing</a> in Australia. Farming the sea is hailed as a vital source of food and biomass essential to reduce the damage we do to our oceans and <a href="https://academic.oup.com/bioscience/article/59/11/967/251334">help feed a growing population</a>.</p>
<p>But the booming “<a href="https://www.tandfonline.com/doi/full/10.1080/09733159.2016.1175131">blue economy</a>” is no panacea. Fish farms can pollute the water. Mangroves are often felled to make way for prawn farms. The solutions of today could turn out to be <a href="https://link.springer.com/article/10.1007/s11160-020-09628-6">problems of the future</a>. We cannot simply shift from one form of environmental exploitation to another. </p>
<p>There is an alternative: permaculture. This approach has proven itself on land as a way to blend farming with healthy ecosystems. What if it could do the same on water? </p>
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Read more:
<a href="https://theconversation.com/farming-fish-in-fresh-water-is-more-affordable-and-sustainable-than-in-the-ocean-151904">Farming fish in fresh water is more affordable and sustainable than in the ocean</a>
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<h2>Making aquaculture better</h2>
<p>Many of today’s most pressing problems – from climate change to biodiversity loss to pollution – are <a href="https://foodsystemeconomics.org/wp-content/uploads/FSEC-Executive_Summary-Global_Policy_Report.pdf">linked to the way</a> we produce food on land. To make new farmland often involves removing habitat, destroying trees and adding synthetic fertilisers and pesticides.</p>
<p>Since humans began farming about 12,000 years ago, we have expanded to the point where we now <a href="https://www.ipcc.ch/srccl/chapter/summary-for-policymakers/">actively control about 70%</a> of Earth’s ice-free land to make food, build cities, and many other uses. </p>
<p>On land, we are farmers, tending domesticated species. But at sea, we’ve been hunters, seeking wild populations. Now, the seas are to be farmed. We should farm in ways which do not damage these ecosystems.</p>
<p>We cannot afford to use the same intensive methods of farming in the oceans as we have been on land. Given how sick many of the world’s ocean systems are already from overfishing, algal blooms from nutrient overload, and habitat loss, there’s not much room for error. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/574278/original/file-20240208-20-e8eu7y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="prawn farms in Thailand" src="https://images.theconversation.com/files/574278/original/file-20240208-20-e8eu7y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/574278/original/file-20240208-20-e8eu7y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/574278/original/file-20240208-20-e8eu7y.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/574278/original/file-20240208-20-e8eu7y.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/574278/original/file-20240208-20-e8eu7y.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/574278/original/file-20240208-20-e8eu7y.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/574278/original/file-20240208-20-e8eu7y.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=565&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">It’s entirely possible for aquaculture to be done too intensively.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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<h2>What is marine permaculture?</h2>
<p>Permaculture as we know it was developed in the 1960s by Australians Bill Mollison and David Holmgren. The latter is a co-author of the research forming the basis of this article. </p>
<p>The goal was simple: create ways of farming which give back to the soil and ecosystems, using tools like no-till farming, companion planting and food forests. Over the last 50 years, it has been adopted by farmers around the world.</p>
<p>Permaculture is framed around three ethics – care of Earth, care of people, and a fair share – aimed at producing benefits and distributing costs equitably between different people and nature. </p>
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Read more:
<a href="https://theconversation.com/let-them-eat-carp-fish-farms-are-helping-to-fight-hunger-90421">Let them eat carp: Fish farms are helping to fight hunger</a>
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<p>So what would permaculture of the seas look like? While it hasn’t been fully articulated, many recent developments in ocean production and governance have strong parallels with the work permaculture practitioners have been doing for decades. </p>
<p>Aquaculture systems can, many now believe, not only be low-impact but work to <a href="https://conbio.onlinelibrary.wiley.com/doi/full/10.1111/csp2.12982">restore lost or damaged ecosystems</a>. Picture oyster farms slowly bringing back the natural oyster reefs which once carpeted shallow coastal waters, or prawn farms surrounded by regrowing mangroves to protect the coast from erosion. </p>
<p>There are strong parallels between the closed-loop approach taken by permaculture on land and an emerging sea farming approach called integrated multi-trophic aquaculture. Here, species with different ecological roles are grown together, producing more food from your farm – and strengthening <a href="https://www.frontiersin.org/articles/10.3389/fmars.2018.00165/full">natural ecosystem services</a>. </p>
<p>In these systems, food waste from consumers is recycled by seaweeds and shellfish, which in turn provide food and habitat to farmed fish species. If well-designed, these benefits flow out from the farm. </p>
<p>Permaculture’s influence is also evident in <a href="https://academic.oup.com/pnasnexus/article/1/4/pgac196/6702749">nature-inspired design and biomimicry</a>, using natural shapes to give nature a boost. Australian work here includes efforts to restore rocky reefs by <a href="https://www.theage.com.au/national/victoria/like-sculptures-in-the-sea-artificial-reef-brings-hope-to-threatened-shoreline-20231018-p5edci.html">creating structures</a> with the nooks and crannies small sea creatures need. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/574279/original/file-20240208-26-t5obr6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="fish farms seen from above" src="https://images.theconversation.com/files/574279/original/file-20240208-26-t5obr6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/574279/original/file-20240208-26-t5obr6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=337&fit=crop&dpr=1 600w, https://images.theconversation.com/files/574279/original/file-20240208-26-t5obr6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=337&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/574279/original/file-20240208-26-t5obr6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=337&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/574279/original/file-20240208-26-t5obr6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/574279/original/file-20240208-26-t5obr6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/574279/original/file-20240208-26-t5obr6.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"></a>
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<span class="caption">Fish farming is becoming big business. But that comes with risks.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/salmon-fish-farm-hordaland-norway-703043050">Marius Dobilas/Shutterstock</a></span>
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<h2>From the grassroots</h2>
<p>At present, a handful of corporations have disproportionately high <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0127533">levels of control over fisheries and aquaculture</a>. In part, that’s because <a href="https://www.msc.org/en-au/what-we-are-doing/our-approach/fishing-methods-and-gear-types/can-a-super-trawler-fish-sustainably">supertrawlers</a>, <a href="https://www.abc.net.au/news/rural/2023-08-08/sea-swift-prawn-trawler-motherships-gulf-of-carpentaria/102696476">motherships</a>, and large blue-water fish farms are expensive.</p>
<p>If we instead took a marine permaculture approach to the blue economy, we would seek to return power back to the people who live and work at the water’s edge – a permaculture equivalent to <a href="https://news.mongabay.com/2023/01/mongabay-explains-whats-the-difference-between-artisanal-and-industrial-fishing/">artisanal fishing</a>. </p>
<p>A localised approach to aquaculture has real benefit. Individuals and communities could develop their own versions of marine permaculture which work in their area, by adopting design solutions used elsewhere or just by tinkering and trialing. </p>
<p>If something isn’t working or it’s creating flow-on consequences, people can see what’s happening and respond quickly. </p>
<p>Small-scale sea farms are less likely to do damage, and should also boost resilience by investing in local social and environmental benefits.</p>
<h2>How do we make this a reality?</h2>
<p>For their part, governments can help by creating policy frameworks encouraging small-scale producers – especially those able to demonstrate positive social and ecological outcomes. </p>
<p>Governments have an essential role in creating comprehensive <a href="https://www.sciencedirect.com/science/article/pii/S0308597X10000436">spatial plans</a> to guide aquaculture in an area or region. This is important, as it removes uncertainty and avoids conflict between different uses. </p>
<p>Researchers can help by developing measures of success and testing new techniques to help guide the new communities which will form to farm the sea.</p>
<p>Over the past half-century, permaculture on land has grown into a diverse movement challenging conventional wisdom about how to produce food. </p>
<p>We’ll need that same intense creative energy to make marine permaculture a reality. It’s entirely possible to design food-producing seascapes which give back to the sea as well as take from it – while making it possible for smaller sea farmers to flourish. </p>
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Read more:
<a href="https://theconversation.com/a-revolution-disguised-as-organic-gardening-in-memory-of-bill-mollison-66137">A revolution disguised as organic gardening: in memory of Bill Mollison</a>
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<p><em>Climate Foundation CEO Brian von Herzen and permaculture pioneer David Holmgren contributed to the research this article is based on.</em></p><img src="https://counter.theconversation.com/content/222514/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Scott Spillias 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>As we go from fishing to fish farming, we should borrow restorative approaches from permaculture.Scott Spillias, Postdoctoral Research Fellow, CSIROLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2178682023-12-14T19:00:58Z2023-12-14T19:00:58ZMutton, an Indigenous woolly dog, died in 1859 − new analysis confirms precolonial lineage of this extinct breed, once kept for their wool<figure><img src="https://images.theconversation.com/files/562497/original/file-20231129-22-cxtdyy.jpg?ixlib=rb-1.1.0&rect=0%2C444%2C2995%2C2883&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Indigenous Coast Salish women wove woolly dogs' fur into blankets.</span> <span class="attribution"><span class="source">Artist's reconstruction by Karen Carr</span></span></figcaption></figure><p>Dogs have been in the Americas for more than 10,000 years. They were already domesticated when they <a href="https://doi.org/10.1126/science.aao4776">came from Eurasia with the first people</a> to reach North America. In the coastal parts of present-day Washington state and southwestern British Columbia, archaeologists have found dog remains dating back as far as <a href="https://doi.org/10.1016/j.jaa.2020.101209">about 5,000 years ago</a>.</p>
<p>Dogs performed many different roles in North American Indigenous communities, including transportation, that in other parts of the world were done by multiple other domestic animals. </p>
<p>Prior to the arrival of Europeans, the <a href="https://www.burkemuseum.org/collections-and-research/culture/contemporary-culture/coast-salish-art/coast-salish-people">Indigenous Coast Salish peoples</a> of the Pacific Northwest had traditionally maintained a breed of long-haired dog for the purpose of harvesting their hair, or wool, for textile fibers. Along with <a href="https://doi.org/10.1016/0305-4403(95)90012-8">alpacas and llamas</a>, these woolly dogs are one of only a few known animals intentionally bred for their fleece in all of the Americas.</p>
<p>But the practice of keeping woolly dogs and weaving textiles made from woolly dog yarn declined throughout the 19th century, and the dogs were considered extinct by the beginning of the 20th century. What had happened to them? </p>
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<a href="https://images.theconversation.com/files/562505/original/file-20231129-19-wyniuw.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="dog paw on furry pelt with handwritten tag" src="https://images.theconversation.com/files/562505/original/file-20231129-19-wyniuw.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/562505/original/file-20231129-19-wyniuw.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/562505/original/file-20231129-19-wyniuw.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/562505/original/file-20231129-19-wyniuw.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/562505/original/file-20231129-19-wyniuw.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/562505/original/file-20231129-19-wyniuw.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/562505/original/file-20231129-19-wyniuw.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>
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<span class="caption">Mutton’s pelt has been preserved at the Smithsonian Institution for more than 160 years.</span>
<span class="attribution"><span class="source">Audrey Lin</span></span>
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<p>Today, the only confirmed woolly dog specimen is “Mutton,” whose pelt has been housed <a href="http://n2t.net/ark:/65665/3299968b9-99b2-4db0-9aee-b8ee388fcb57">in the Smithsonian’s collection</a> since his death in 1859. In life, this “Indian dog” was the companion of <a href="https://en.wikipedia.org/wiki/George_Gibbs_(ethnologist)">George Gibbs</a>, a naturalist working on the Northwest Boundary Survey expedition to map out British Columbia and the American Pacific Northwest. In death, Mutton offered the opportunity to learn more about woolly dog ancestry, selection and management.</p>
<p>We are <a href="https://scholar.google.com/citations?user=th7mXK0AAAAJ&hl=en&oi=ao">an archaeologist</a>, an <a href="https://scholar.google.com/citations?user=5sYVrEsAAAAJ&hl=en&oi=ao">evolutionary molecular biologist</a> and a <a href="https://scholar.google.com/citations?user=G5OGkjUAAAAJ&hl=en&oi=ao">molecular anthropologist</a> who are part of a large research team. It’s important to note that although we collaborated with a number of Indigenous people on our study, the scientists, including the three of us, are not Indigenous. Alongside historical documents and interviews of Coast Salish elders, knowledge keepers, weavers and artists, our team utilized “<a href="https://doi.org/10.1111/faf.12516">Two-Eyed Seeing</a>” – viewing the world through the combined strengths of Indigenous knowledge and western science – to <a href="https://doi.org/10.1126/science.adi6549">bring Mutton’s story and legacy back to life</a>.</p>
<h2>A prestigious part of Indigenous culture</h2>
<p>Prior to the arrival of Europeans, there were <a href="https://archpress.lib.sfu.ca/index.php/archpress/catalog/download/52/23/1900?inline=1">several types of dogs</a> in the Pacific Northwest: larger “village” dogs and hunting dogs and smaller <a href="https://hakaimagazine.com/features/the-dogs-that-grew-wool-and-the-people-who-love-them/">woolly dogs</a>, kept separately to prevent interbreeding. Woolly dogs were a little larger than the modern <a href="https://www.akc.org/dog-breeds/american-eskimo-dog/">American Eskimo dog breed</a> and had curled tails, pricked ears and a pointed foxlike face. Instead of barking, they howled. </p>
<p>Traditionally, only high-status Coast Salish women were allowed to keep woolly dogs, and a woman’s individual wealth could be measured by how many she had. Blankets woven of dog hair, often mixed with hair from mountain goats and waterfowl or plant fibers, were important trade and gift items.</p>
<p>Historians and economists, looking back, first claimed the disappearance of the woolly dog breed was the result of simple capitalist forces: The availability of cheap manufactured blankets offered by businesses like the <a href="https://www.hbcheritage.ca/things/fashion-pop/hbc-point-blanket">Hudson’s Bay Company</a> meant the Coast Salish didn’t need to make their own blankets. Why go through the immense time and labor in keeping wool dogs and crafting blankets in the traditional way when you could just buy a machine-woven blanket? </p>
<p>But the Coast Salish don’t agree. <a href="https://vanmuralfest.ca/blog/debra-sparrow">Debra qwasen Sparrow</a>, a master weaver of the <a href="https://www.musqueam.bc.ca/">Musqueam Nation</a>, explained to us, “The blankets really tell a story of our history, our families, the way in which they identified in the communities, (they’re) all reflected in the blankets.”</p>
<p>And Coast Salish people say they would never have willingly parted with their beloved canine friends. The simple economic explanation ignores the massive role colonialism played in the demise of the woolly dogs. Repressive government policies <a href="https://www.washington.edu/uwired/outreach/cspn/Website/Classroom%20Materials/Pacific%20Northwest%20History/Lessons/Lesson%2012/12.html">tried to control and subdue</a> <a href="https://www.kitsapsun.com/story/news/2022/05/12/indian-boarding-schools-operated-washington-state-interior-department-deb-haaland/9749676002/">Indigenous cultural practices</a>.</p>
<p>“They were told they couldn’t do their cultural things. There was the police, the Indian agent and the priests,” <a href="https://www.stolonation.bc.ca">Stó:lō Nation</a> elder Xweliqwiya Rena Point Bolton told our research team. “The dogs were not allowed. (My grandmother) had to get rid of the dogs. And so the family never ever saw them.”</p>
<p>Eventually, there were no more Coast Salish woolly dogs.</p>
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<a href="https://images.theconversation.com/files/565318/original/file-20231212-23-cut1vu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="pelt fur-side down on a paper-covered table" src="https://images.theconversation.com/files/565318/original/file-20231212-23-cut1vu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/565318/original/file-20231212-23-cut1vu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=468&fit=crop&dpr=1 600w, https://images.theconversation.com/files/565318/original/file-20231212-23-cut1vu.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=468&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/565318/original/file-20231212-23-cut1vu.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=468&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/565318/original/file-20231212-23-cut1vu.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=588&fit=crop&dpr=1 754w, https://images.theconversation.com/files/565318/original/file-20231212-23-cut1vu.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=588&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/565318/original/file-20231212-23-cut1vu.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=588&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Researchers used a portable X-ray fluorescence analyzer as part of their investigation of Mutton’s remains.</span>
<span class="attribution"><span class="source">Audrey Lin</span></span>
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<h2>Piecing together a picture of Mutton’s life</h2>
<p>We did have access to Mutton’s pelt, though, which had been archived for more than 160 years. No one knows exactly how Gibbs initially acquired Mutton, but it’s likely he got the dog while working with local communities in <a href="https://www.stolonation.bc.ca/">Stó:lō territory</a> in present-day British Columbia. Using modern techniques, we set out to answer questions about Mutton’s breed and ancestry.</p>
<p>First we used <a href="https://www.nature.com/scitable/knowledge/library/the-use-of-stable-isotopes-in-the-96648168/">stable isotope analysis</a>, a chemical analysis of once-living tissues, to understand more about Mutton’s environment when he was alive: what kinds of foods he ate and the state of his health.</p>
<p>Interviews of the <a href="https://doi.org/10.1126/science.adi6549">elders and knowledge keepers confirmed</a> that the woolly dog diet was very different from village dogs, including special foods that kept the dogs healthy and their coats shiny. For example, salmon, elk or certain local plants would be set aside for the woolly dogs. </p>
<p>The stable isotope values of Mutton’s fur suggested he’d been eating maize for some time, but less and less up to the point when he died. The <a href="https://www.trafford.com/en/bookstore/bookdetails/407988-Joseph-S-Harris-and-the-U-S-Northwest-Boundary-Survey-1857-1861">letters of one expedition member</a> imply they were running low on cornmeal and supplementing their imported supplies by trading with locals. Although <a href="https://siarchives.si.edu/sites/all/modules/sia/sia_mirador/mirador/mirador_player3?manifest=https://iiif.si.edu/manifests/siarchives/SIA-007209_B01_F02_MODSI1328.json">Gibbs noted in his journal</a> that Mutton was ill before he died, there was no isotopic evidence to support chronic illness; Mutton may have become sick quickly.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/565265/original/file-20231212-23-zikxpo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Scientist with blue gloves uses a tool to lift a bit of hair from the pelt" src="https://images.theconversation.com/files/565265/original/file-20231212-23-zikxpo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/565265/original/file-20231212-23-zikxpo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/565265/original/file-20231212-23-zikxpo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/565265/original/file-20231212-23-zikxpo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/565265/original/file-20231212-23-zikxpo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/565265/original/file-20231212-23-zikxpo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/565265/original/file-20231212-23-zikxpo.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">Chris Stantis carefully removes a minimal sample from Mutton’s pelt for further analyses.</span>
<span class="attribution"><span class="source">Hsiao-Lei Liu</span></span>
</figcaption>
</figure>
<p>Next, we turned to genetic analysis for insight into the dog’s ancestry to understand long-term management of this breed. We sequenced Mutton’s DNA and compared it with a contemporaneous village dog that was killed by the explorers in an unknown village in the Pacific Northwest. We also compared Mutton’s DNA with a genetic panel of many other modern and ancient dogs.</p>
<p><a href="https://doi.org/10.1126/science.adi6549">We found that Mutton</a> is a rare example of an Indigenous North American dog with precolonial ancestry who lived well after the arrival of white settlers. Using a dataset of mitochondrial genomes from Mutton and more than 200 ancient and modern dogs, we made an elaborate family tree. Called a <a href="http://dunnlab.org/phylogenetic_biology/phylogenies-and-time.html">time-calibrated phylogenetic tree</a>, it creates a diagram of the evolution of Mutton’s maternal lineage.</p>
<p>Based on the tree, we estimate that Mutton’s most recent common ancestor diverged from one other ancient dog from British Columbia between 1,800 and 4,800 years ago, corresponding with the known archaeological record. In other words, Mutton’s woolly dog lineage has been isolated from other dogs for millennia.</p>
<p>We see evidence of inbreeding in Mutton’s genome that can result only from careful long-term selective breed management. We identified variants of genes associated with hair and skin, including KRT77 and KANK2, which are linked to <a href="https://doi.org/10.1136/jmedgenet-2014-102346">woolly hair in humans</a>. </p>
<p>However, Mutton lived during a very volatile <a href="https://www.nps.gov/places/the-fraser-river-gold-rush.htm">time period</a>. For example, in 1858 more than 33,000 miners flooded into present-day British Columbia in <a href="https://www.thecanadianencyclopedia.ca/en/article/fraser-river-gold-rush">search of gold</a>. This influx left its mark in Mutton’s DNA, and we found that about one eighth of his genome – representating about one great-grandparent’s worth of DNA – came from settler-introduced European dogs. </p>
<p>Finally, we worked closely with a <a href="https://www.karencarr.com/">scientific artist</a>, using archaeological dog bones and Mutton’s pelt, to reconstruct what these dogs looked like in life with scientific accuracy.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/562506/original/file-20231129-21-3c76dg.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="zig-zag patterened blanket with fringe on three sides" src="https://images.theconversation.com/files/562506/original/file-20231129-21-3c76dg.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/562506/original/file-20231129-21-3c76dg.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=433&fit=crop&dpr=1 600w, https://images.theconversation.com/files/562506/original/file-20231129-21-3c76dg.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=433&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/562506/original/file-20231129-21-3c76dg.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=433&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/562506/original/file-20231129-21-3c76dg.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=544&fit=crop&dpr=1 754w, https://images.theconversation.com/files/562506/original/file-20231129-21-3c76dg.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=544&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/562506/original/file-20231129-21-3c76dg.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=544&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 Coast Salish classic-style blanket, which has woolly dog hair in the warp fibers that were stretched across the loom. Accessioned 1838-1842.</span>
<span class="attribution"><span class="source">USNM E2124, Smithsonian National Museum of Natural History</span></span>
</figcaption>
</figure>
<h2>What this woolly dog confirms about the past</h2>
<p>With Mutton’s pelt, our team wove together these different ways of exploring the many lives of Mutton – his ancestry as an Indigenous dog, his life traveling with white settlers, and finally his time in the Smithsonian Institution.</p>
<p>Mutton is the latest dog we’re aware of with that much precolonial dog ancestry. European colonization was devastating to Indigenous people in North America. The fact that Mutton carries as much Indigenous dog DNA as he does is a testament to the care that Coast Salish people took to keep the woolly dog tradition alive.</p>
<p>Our Coast Salish weaving collaborators are very keen to learn more about how traditional blankets housed in museum collections are made – to inform efforts to revive complex techniques and better understand the unique materials used. With Mutton’s genetic sequencing, future researchers may be able to identify dog hair in heritage woven materials. Some Coast Salish would like to see the woolly dogs return to their families once again. There’s currently no way to bring back the original woolly dogs, such as by cloning Mutton, because his DNA is far too degraded after more than 160 years. But a new kind of woolly dog could be created in the future through <a href="https://www.britannica.com/science/selective-breeding">selective breeding</a> and care.</p>
<p>“But the thing that’s most important (is) that (the) wool dog created a gift to produce and to make something, to create something, to bring something alive,” Michael Pavel, elder of the <a href="https://skokomish.org/culture-and-history/">Twana/Skokomish Tribe</a>, told us. “Let’s do that. Let’s bring that back to life. … The wool dog is still very much a part of our life.”</p><img src="https://counter.theconversation.com/content/217868/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Dogs have lived with Indigenous Americans since before they came to the continent together 10,000 years ago. A new analysis reveals the lineage of one 1800s ‘woolly dog’ from the Pacific Northwest.Audrey T. Lin, Research Associate in Anthropology, Smithsonian InstitutionChris Stantis, Postdoctoral Research Fellow in Geology and Geophysics, University of UtahLogan Kistler, Curator of Archaeobotany and Archaeogenomics, National Museum of Natural History, Smithsonian InstitutionLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2187032023-12-07T05:01:59Z2023-12-07T05:01:59ZIf humans disappeared, what would happen to our dogs?<figure><img src="https://images.theconversation.com/files/563803/original/file-20231206-29-g9446.jpg?ixlib=rb-1.1.0&rect=15%2C15%2C5080%2C3376&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>For many of us, dogs are our best friends. But have you wondered what would happen to your dog if we suddenly disappeared? Can domestic dogs make do without people? </p>
<p>At least 80% of the world’s <a href="https://press.princeton.edu/books/hardcover/9780691196183/a-dogs-world">one billion or so dogs</a> actually live independent, free-ranging lives – and they offer some clues. Who would our dogs be if we weren’t around to influence and care for them?</p>
<h2>What are dogs?</h2>
<p>Dogs hold the title of the most successful domesticated species on Earth. For millennia they have <a href="https://iview.abc.net.au/show/dog-s-world-with-tony-armstrong">evolved under our watchful eye</a>. More recently, selective breeding has led to people-driven diversity, resulting in unique breeds ranging from the towering Great Dane to the tiny Chihuahua. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/562913/original/file-20231201-15-zku7cs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/562913/original/file-20231201-15-zku7cs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/562913/original/file-20231201-15-zku7cs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=392&fit=crop&dpr=1 600w, https://images.theconversation.com/files/562913/original/file-20231201-15-zku7cs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=392&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/562913/original/file-20231201-15-zku7cs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=392&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/562913/original/file-20231201-15-zku7cs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=492&fit=crop&dpr=1 754w, https://images.theconversation.com/files/562913/original/file-20231201-15-zku7cs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=492&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/562913/original/file-20231201-15-zku7cs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=492&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Today’s diverse dog breeds are a result of the modern approach to selective breeding.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>Humanity’s quest for the perfect canine companion has resulted in more than 400 modern dog breeds with unique blends of physical and behavioural traits. Initially, dogs were bred primarily <a href="https://theconversation.com/managing-mutations-of-a-species-the-evolution-of-dog-breeding-96635">for functional roles</a> that benefited us, such as herding, hunting and guarding. This practice only emerged prominently over the past 200 years. </p>
<p>Some experts suggest companionship is just another type of work <a href="https://www.sciencedirect.com/science/article/pii/S0168159122000983">humans selected dogs for</a>, while placing a greater emphasis on looks. Breeders play a crucial role in this, making deliberate choices about which traits are desirable, thereby influencing the future direction of breeds. </p>
<h2>Are we good for dogs?</h2>
<p>We know certain features that appeal to people have serious impacts on <a href="https://theconversation.com/vets-can-do-more-to-reduce-the-suffering-of-flat-faced-dog-breeds-110702">health and happiness</a>. For instance, <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0137496">flat-faced dogs struggle with breathing</a> due to constricted nasal passages and shortened airways. This “<a href="https://www.tandfonline.com/doi/abs/10.1080/00480169.2014.940410">air hunger</a>” has been likened to experiencing an asthma attack. These dogs are also prone to higher rates of skin, eye and dental problems compared with dogs with longer muzzles.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/562919/original/file-20231201-21-o3gi7e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/562919/original/file-20231201-21-o3gi7e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/562919/original/file-20231201-21-o3gi7e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/562919/original/file-20231201-21-o3gi7e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/562919/original/file-20231201-21-o3gi7e.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/562919/original/file-20231201-21-o3gi7e.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/562919/original/file-20231201-21-o3gi7e.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/562919/original/file-20231201-21-o3gi7e.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">Flat-faced dogs such as pugs and bulldogs often aren’t comfortable in the bodies we’ve bred them for.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>Many modern dogs depend on human medical intervention to reproduce. For instance, French Bulldogs and Chihuahuas frequently require a caesarean section to give birth, as the puppies’ heads are <a href="https://kb.rspca.org.au/knowledge-base/what-are-the-welfare-risks-associated-with-difficulty-giving-birth-in-brachycephalic-dogs/">very large compared with</a> the mother’s pelvic width. This reliance on surgery to breed highlights the profound impact intensive selective breeding has on dogs.</p>
<p>And while domestic dogs can benefit from being part of human families, some live highly isolated and controlled lives in which they have little agency <a href="https://frontiersin.org/articles/10.3389/fvets.2023.1284869/">to make choices</a> – a factor that’s important to their happiness.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/in-an-australian-first-the-act-may-legally-recognise-animals-feelings-111079">In an Australian first, the ACT may legally recognise animals' feelings</a>
</strong>
</em>
</p>
<hr>
<h2>Dogs without us</h2>
<p>Now imagine a world where dogs are free from the guiding hand of human selection and care. The immediate impact would be stark. Breeds that are heavily dependent on us for basic needs such as food, shelter and healthcare wouldn’t do well. They would struggle to adapt, and many would succumb to the harsh realities of a life without human support.</p>
<p>That said, this would probably impact fewer than 20% of all dogs (roughly the percentage living in our homes). Most of the world’s dogs are free-ranging and prevalent across Europe, Africa and Asia.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/562921/original/file-20231201-17-4hsi2p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/562921/original/file-20231201-17-4hsi2p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/562921/original/file-20231201-17-4hsi2p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/562921/original/file-20231201-17-4hsi2p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/562921/original/file-20231201-17-4hsi2p.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/562921/original/file-20231201-17-4hsi2p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/562921/original/file-20231201-17-4hsi2p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/562921/original/file-20231201-17-4hsi2p.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">Many dogs live independently around people, like these dogs seen on the street in India.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>But while these dogs aren’t domesticated in a traditional sense, they still coexist with humans. As such, their survival depends almost exclusively on human-made resources such as garbage dumps and food handouts. Without people, <a href="https://theconversation.com/explainer-theory-of-evolution-2276">natural selection</a> would swiftly come into play. Dogs that lack essential survival traits such as adaptability, hunting skills, disease resistance, parental instincts and sociability would gradually decline. </p>
<p>Dogs that are either extremely large or extremely small would also be at a disadvantage, because a dog’s size will impact its caloric needs, body temperature regulation across environments, and susceptibility to predators. </p>
<p>Limited behavioural strategies, such as being too shy to explore new areas, would also be detrimental. And although sterilised dogs might have advantageous survival traits, they would be unable to pass their genes on to future generations.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/563817/original/file-20231206-23-djskol.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/563817/original/file-20231206-23-djskol.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=416&fit=crop&dpr=1 600w, https://images.theconversation.com/files/563817/original/file-20231206-23-djskol.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=416&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/563817/original/file-20231206-23-djskol.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=416&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/563817/original/file-20231206-23-djskol.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=523&fit=crop&dpr=1 754w, https://images.theconversation.com/files/563817/original/file-20231206-23-djskol.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=523&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/563817/original/file-20231206-23-djskol.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=523&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Rearing puppies without human support happens successfully around the world.</span>
<span class="attribution"><a class="source" href="https://www.mdpi.com/2075-4450/14/7/618">Shutterstock</a></span>
</figcaption>
</figure>
<h2>No more designer breeds</h2>
<p>Ultimately, a different type of dog would emerge, shaped by health and behavioural success rather than human desires.</p>
<p>Dogs don’t select mates based on breed, and will readily mate with others that look very different to them when given the opportunity. Over time, distinct dog breeds would fade and unrestricted mating would lead to a uniform “village dog” appearance, similar to “camp dogs” in <a href="https://journals.sagepub.com/doi/full/10.1177/11771801231167671">remote Indigenous Australian communities</a> and dogs seen in South-East Asia.</p>
<p>These dogs typically have a medium size, balanced build, short coats in various colours, and upright ears and tails. However, regional variations such as a shaggier coat could arise due to factors such as climate.</p>
<p>In the long term, dogs would return to a wild canid lifestyle. These “re-wilded” dogs would likely adopt social and dietary behaviours similar to those of their current wild counterparts, <a href="https://www.publish.csiro.au/book/7138/">such as Australia’s dingoes</a>. This might include living in small <a href="https://7news.com.au/news/wildlife/dingo-drone-footage-captured-by-thermal-camera-on-qld-property-shows-family-fun-time-c-12586477">family units within defined territories</a>, reverting to an annual breeding season, engaging in social hunting, and attentive parental care (especially from dads).</p>
<p>This transition would be more feasible for certain breeds, particularly herding types and those already living independently in the wild or as village dogs.</p>
<h2>What makes a good life for dogs?</h2>
<p>In their book <a href="https://press.princeton.edu/books/hardcover/9780691196183/a-dogs-world">A Dog’s World</a>, Jessica Pierce and Marc Bekoff explore the idea of “doomsday prepping” our dogs for a future without people. They encourage us to give our dogs more agency, and consequently more happiness. This could be as simple as letting them pick which direction to walk in, or letting them take their time when sniffing a tree. </p>
<p>As we reflect on a possible future without dogs, an important question arises: are our actions towards dogs sustainable, in their best interests, and true to their nature? Or are they more aligned with our own desires?</p>
<p>By considering how dogs might live without us, perhaps we can find ways to improve their lives with us.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/562914/original/file-20231201-15-2sncwg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/562914/original/file-20231201-15-2sncwg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/562914/original/file-20231201-15-2sncwg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=446&fit=crop&dpr=1 600w, https://images.theconversation.com/files/562914/original/file-20231201-15-2sncwg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=446&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/562914/original/file-20231201-15-2sncwg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=446&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/562914/original/file-20231201-15-2sncwg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=560&fit=crop&dpr=1 754w, https://images.theconversation.com/files/562914/original/file-20231201-15-2sncwg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=560&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/562914/original/file-20231201-15-2sncwg.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">Providing a good life for dogs requires thinking about their mental well-being, health and environment.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure><img src="https://counter.theconversation.com/content/218703/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>If we weren’t here to shape, feed and care for our dogs – how might they change?Bradley Smith, Senior Lecturer in Psychology, CQUniversity AustraliaMia Cobb, Research Fellow, Animal Welfare Science Centre, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2114622023-10-22T11:15:32Z2023-10-22T11:15:32ZAncient pots hold clues about how diverse diets helped herders thrive in southern Africa<p>The introduction of herding – a way of life which centres on keeping herds of mobile domesticated animals – significantly changed Africa’s <a href="https://doi.org/10.1016/J.CELL.2017.08.049">genetic</a>, economic, <a href="https://doi.org/10.1006/jaar.1998.0323">social and cultural</a> landscapes during the last 10,000 years. Unlike other parts of the world, mobile herding spread throughout the continent thousands of years before farming and did not replace foraging in many places. This gave rise to complex mosaics of foragers and food producers across sub-Saharan Africa. </p>
<p>Once herding reached southern Africa during the <a href="https://doi.org/10.1017/S0003598X00046196">early first millennium AD</a>, it spread rapidly throughout the region, in part because of presumed <a href="https://doi.org/10.1371/journal.pone.0113672">local adoption</a> of sheep by diverse groups of foragers. Since these foragers and herders left similar types of artefacts it is difficult to pinpoint who was herding in the archaeological record, their dietary choices, and how this way of life spread. </p>
<p>Traditional archaeological data alone – such as the types of animal bones present at sites – can’t always help. So, researchers need to combine multiple lines of evidence from both traditional and biomolecular archaeology, which involves studying ancient lipids (fats) and proteins.</p>
<p>I am an anthropological archaeologist whose research focuses on understanding how herders thrived in the Namaqualand coastal desert of South Africa over the last 2,000 years. </p>
<p>Recently I was part of a research team that wanted to better understand how ancient herders in Namaqualand incorporated sheep into their diet. We <a href="https://doi.org/10.1038/s41598-023-28577-1">analysed the residues of past meals preserved in archaeological pottery</a>. By analysing lipids entrapped in ancient pottery we found evidence for dairy fats. </p>
<p>This may seem, at first glance, to be merely historical curiosity with no current applications. But in reality, conducting this research now – while herding is still a viable economic activity in Namaqualand – can contribute to the broader discussion about climate resilient landscape use. Herding initially spread to Namaqualand amid environmental, economic and social change. Similar forces threaten the practice’s future. Understanding how ancient herders managed their herds in an unpredictable environment may offer insights for altering or refining current practices.</p>
<h2>Studying the pots</h2>
<p>Namaqualand, which covers around 50,000km², is located in the westernmost part of South Africa’s Northern Cape province. </p>
<p>It is bounded by the Atlantic Ocean to the west, the Kamiesberg Mountains about 100km to the east, the Oliphants River to the south and the Orange River to the north. This semi-arid desert has an <a href="https://doi.org/10.1023/A:1009831308074">average annual rainfall of 150mm</a>; more than 66% of that falls in the winter months. The largest town in the region is Springbok, with a population of just under <a href="https://www.statssa.gov.za/?page_id=4286&id=6898">13,000</a>. </p>
<p>There generally aren’t many livestock bones present at archaeological sites in the region. This is because herders were highly mobile, with small herds, and didn’t regularly consume their sheep. </p>
<p>However, there is an archaeological resource that exists in abundance: pottery sherds. These contain microscopic traces of the ancient meals cooked in them. Analysing these pottery-bound lipids using a method called <a href="https://www.youtube.com/watch?v=nxNMm78tvrI">organic residue analysis</a> allows researchers to identify ruminant (for example sheep, cow, antelope), non-ruminant (for example seal, shellfish, fish), and ruminant dairy fats that were cooked in the pots. Finding dairy fats in pottery provides evidence for livestock when their bones are absent or unidentifiable at archaeological sites. </p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/chemical-traces-in-ancient-west-african-pots-show-a-diet-rich-in-plants-177579">Chemical traces in ancient West African pots show a diet rich in plants</a>
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<p>We <a href="https://www.nature.com/articles/s41598-023-28577-1">analysed pottery</a> from four archaeological sites in the region dated to between AD 137 and AD 1643 to help unravel the dietary choices of ancient herders and foragers in Namaqualand. </p>
<p>The two inland sites located along the Orange River <a href="https://ora.ox.ac.uk/objects/uuid:eb329a96-a52f-4ba2-bdfd-73c73293d99e">contained</a> the <a href="https://sahris.sahra.org.za/sites/default/files/heritagereports/9-2-066-0034-20010901-ACO_0.pdf">remains of domesticated animals and pottery</a>. The two coastal sites did not contain domesticate remains but <a href="https://ora.ox.ac.uk/objects/uuid:eb329a96-a52f-4ba2-bdfd-73c73293d99e">did</a> contain <a href="https://open.uct.ac.za/items/f09f3b8b-4c06-4f18-a891-1719f5a5c5ab">pottery</a>, generally regarded as a proxy for herders.</p>
<p>We found that the people using these pots ate a variety of foodstuff including ruminant and non-ruminant animal fats. We also found the first direct evidence for people processing milk in South African pottery. </p>
<p>These findings suggest that low-intensity herders living in Namaqualand during the period we studied didn’t rely solely on their domesticated animals for all or even most of their daily dietary needs. Instead they had diverse diets and relied on a range of species for daily subsistence.</p>
<h2>Looking ahead</h2>
<p>Our next step is to characterise the ceramic-bound proteins preserved in the pottery. Organic residue analysis is a powerful tool. But it can only separate lipids into broad categories (dairy, ruminant, non-ruminant). Ceramic-bound proteins, meanwhile, are similar to DNA in that they encode fundamental genetic information that is key to identifying species. This species-level data is vital since early food producer sites consist of wild and domestic species that look similar.</p>
<p>Though this research focuses on the distant past, it has applications today, too. </p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/livestock-are-threatened-by-predators-but-old-fashioned-shepherding-may-be-an-effective-solution-201193">Livestock are threatened by predators – but old-fashioned shepherding may be an effective solution</a>
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</em>
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<hr>
<p>In Namaqualand, herding remains an important livelihood for many: <a href="https://www.statssa.gov.za/?page_id=735&id=4=1">60% of households</a> participate in some form of daily herding activity. Globally, many herders face <a href="https://doi.org/10.1016/j.gfs.2020.100488">serious water, food, and pasture scarcity</a>. Herders in Namaqualand are being exposed to extreme temperatures and often have severely <a href="https://doi.org/10.1016/j.envdev.2018.12.001">limited access</a> to water and pasture.</p>
<p>So, this more targeted type of research on the resource use and subsistence decisions of archaeological herders who thrived in an unpredictable environment is important and timely.</p><img src="https://counter.theconversation.com/content/211462/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Courtneay Hopper receives funding from the Social Science and Humanities Research Council (SSHRC).</span></em></p>Archaeological data alone can’t always help to answer researchers’ questions: multiple lines of evidence are needed.Courtneay Hopper, Postdoctoral researcher and Lecturer in Anthropology, University of British ColumbiaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2059942023-10-20T21:17:54Z2023-10-20T21:17:54ZDid Australia’s First Peoples domesticate dingoes? They certainly buried them with great care<figure><img src="https://images.theconversation.com/files/544721/original/file-20230825-29-dja0ah.jpg?ixlib=rb-1.1.0&rect=335%2C323%2C1347%2C940&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>Dingoes are an iconic Australian wild animal, <a href="https://theconversation.com/living-blanket-water-diviner-wild-pet-a-cultural-history-of-the-dingo-80189">with close links</a> to Australia’s First Peoples throughout the mainland. Yet the origins and history of these animals are shrouded in obscurity.</p>
<p>The question of whether dingoes are a <a href="https://zslpublications.onlinelibrary.wiley.com/doi/full/10.1111/jzo.12134">truly wild</a> or formerly domestic animal that <a href="https://theconversation.com/dingoes-dogs-and-the-feral-identity-11635">has become feral</a> has eluded a clear answer or consensus amongst scientists for well over a century. </p>
<p>Published in <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0286576">PLOS One today</a>, our new study of dingoes buried alongside First Nations people in ancient times has provided crucial clues to this mystery. Our findings may help change the way we think about the connections between dingoes and people.</p>
<h2>Living alongside people</h2>
<p>When outsiders observed traditional First Peoples’ societies in the 19th and 20th centuries throughout mainland Australia, they noticed many took dingo pups from wild dens and raised them to keep as companions and <a href="https://www.mdpi.com/2076-2615/12/17/2285">for a variety of other purposes</a> including as guards, hunting aids and living “blankets”.</p>
<p>However, these dingoes always returned to the bush to find a mate after reaching about a year of age, seemingly never to return. This is quite unlike our domestic dogs – they may wander, but ultimately tend to stay with their human families in the long term.</p>
<p>The fact most dingoes live without any reliance on people is one of <a href="https://pubmed.ncbi.nlm.nih.gov/31716519/">the main reasons</a> scientific opinion differs over whether dingoes should be thought of as domestic animals or not.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/544720/original/file-20230825-29-am7gat.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Close-up of very red coarse sand with several paw prints." src="https://images.theconversation.com/files/544720/original/file-20230825-29-am7gat.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/544720/original/file-20230825-29-am7gat.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/544720/original/file-20230825-29-am7gat.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/544720/original/file-20230825-29-am7gat.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/544720/original/file-20230825-29-am7gat.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/544720/original/file-20230825-29-am7gat.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/544720/original/file-20230825-29-am7gat.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">Dingo tracks in the red desert sand of central Australia.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/dingo-canis-tracks-native-wolf-dog-1389629552">Shutterstock</a></span>
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</figure>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/new-dna-testing-shatters-wild-dog-myth-most-dingoes-are-pure-206397">New DNA testing shatters 'wild dog' myth: most dingoes are pure</a>
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<hr>
<p>But is it possible different arrangements between dingoes and Australia’s First Peoples existed before traditional ways of life were disrupted by colonial violence, displacement and disease? Answers might be found in the bones of dingoes that lived with people and were buried after death. </p>
<p>There are historical accounts of funerary and burial rituals of deceased tamed dingoes. Skeletons of dingoes or dogs have been found alongside First Peoples’ burials in many areas of Australia from <a href="https://www.tandfonline.com/doi/abs/10.1080/03122417.2010.11689380">Arnhem Land</a> to the <a href="https://www.tandfonline.com/doi/abs/10.2752/175303713X13636846944088">Murray-Darling</a> basin, but to date there’s been no comprehensive study of this important cultural practice.</p>
<p>In a search of historical records and findings of dingo burials, we found they were concentrated in the Murray-Darling Basin and on the southern coastlines of New South Wales and Victoria. A secondary, more recent cluster was located in north-western Australia.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/528499/original/file-20230526-23-5faty3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A map of Australia showing a few locations of dingo burials with yellow dots" src="https://images.theconversation.com/files/528499/original/file-20230526-23-5faty3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/528499/original/file-20230526-23-5faty3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=424&fit=crop&dpr=1 600w, https://images.theconversation.com/files/528499/original/file-20230526-23-5faty3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=424&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/528499/original/file-20230526-23-5faty3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=424&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/528499/original/file-20230526-23-5faty3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=533&fit=crop&dpr=1 754w, https://images.theconversation.com/files/528499/original/file-20230526-23-5faty3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=533&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/528499/original/file-20230526-23-5faty3.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"></a>
<figcaption>
<span class="caption">Map of Australia illustrating the distribution of dingo burials reported in archaeological, historical and news literature.</span>
<span class="attribution"><span class="source">Loukas Koungoulos</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h2>Buried alongside people</h2>
<p>Historical records and archaeological evidence both show that when dingoes were buried, it was invariably in the manner in which people were buried in the same region. Often, dingoes were buried alongside people.</p>
<p>The act of burial implies a degree of care and belonging to a community. Some archaeologists argue animal burial is a <a href="https://www.sciencedirect.com/science/article/abs/pii/S0305440305001597?via%3Dihub">fundamental sign of domestication</a>. But by examining the skeletons of buried dingoes we can further investigate the life histories of these important animals. </p>
<p>The archaeological site of Curracurrang, a rock shelter in the Royal National Park just south of Sydney, was excavated <a href="https://www.journals.uchicago.edu/doi/abs/10.1086/200906?journalCode=ca">in the 1960s</a>. The excavations found First People were buried there over many centuries.</p>
<p>But our new primary investigations of previously unstudied animal bones reveal the site also contained the skeletons of several dingoes. Radiocarbon dates taken from their bones found the earliest of these were buried around 2,300–2,000 years ago. Dingo burials continued here until the colonial era. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/528500/original/file-20230526-25-5fzgqw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Several bone fragments and teeth on a white background" src="https://images.theconversation.com/files/528500/original/file-20230526-25-5fzgqw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/528500/original/file-20230526-25-5fzgqw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=284&fit=crop&dpr=1 600w, https://images.theconversation.com/files/528500/original/file-20230526-25-5fzgqw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=284&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/528500/original/file-20230526-25-5fzgqw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=284&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/528500/original/file-20230526-25-5fzgqw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=356&fit=crop&dpr=1 754w, https://images.theconversation.com/files/528500/original/file-20230526-25-5fzgqw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=356&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/528500/original/file-20230526-25-5fzgqw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=356&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Mandibular and dental fragments of one of the dingo burials from Curracurrang; this was an elderly individual with highly worn teeth, suggesting a lifetime of crunching bones discarded by people.</span>
<span class="attribution"><span class="source">Loukas Koungoulos</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>Some of the dingoes were adults, at least six to eight years old – well past the age at which they’d be expected to return to the wild to breed. They had severely worn teeth, indicating a diet heavy in large bones, likely from the scraps of human meals.</p>
<p>In addition, one dingo showed signs of suffering from an aggressive, mobility-restricting form of cancer in the last weeks of its life. It was likely looked after by people during its decline.</p>
<p>Several other burials were pups, less than a month or two in age. Since dingoes of breeding age were also found at Curracurrang, it is entirely probable some of these pups were born there but did not survive long, and were buried soon after. These individuals are the first known evidence of dingo pup burial in Australia. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/barkindji-custodians-near-broken-hill-continue-to-care-for-ancestral-dingo-remains-with-help-from-archaeologists-215457">Barkindji custodians near Broken Hill continue to care for ancestral dingo remains with help from archaeologists</a>
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</p>
<hr>
<h2>A previously obscured relationship</h2>
<p>Dingo burials reveal aspects of the relationship between Australia’s First Peoples and their dingo companions which had been, until now, obscured.</p>
<p>At Curracurrang, tame dingoes lived to advanced ages alongside people. They ate the same foods and possibly even bore litters of pups within human camps. While traditional views of domestication involve <a href="https://theconversation.com/why-do-animals-living-with-humans-evolve-such-similar-features-a-new-theory-could-explain-domestication-syndrome-201765">dramatic transformations in appearance</a> and human control over animal reproduction, newer perspectives focus on long-lasting relationships between people and animals. </p>
<p>The evidence from Curracurrang suggests some dingoes, at least in certain settings, were domesticated in ancient times. This doesn’t mean all dingoes were domesticated, nor does it conclusively indicate they originate from domestic dogs. </p>
<p>Most dingoes were, and still are, wild animals with various adaptations to life independent of people in Australian environments. </p>
<p>However, the new findings do mark an important development in our understanding of the deep antiquity and closeness of the connection between Australia’s First Peoples and their native dogs. It attests to long-lasting relationships beyond the transient, temporary associations recorded during the colonial era. </p>
<hr>
<p><em>Acknowledgments: we are grateful to the La Perouse Local Aboriginal Land Council and community for their permission to undertake research on the Curracurrang dingo remains. We also give thanks to the Australian Museum for facilitating access to these materials.</em></p><img src="https://counter.theconversation.com/content/205994/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Loukas Koungoulos receives funding from The Australian Research Council.</span></em></p><p class="fine-print"><em><span>Jane Balme receives funding from The Australian Research Council.</span></em></p><p class="fine-print"><em><span>Shane Ingrey is a member of the La Perouse Aboriginal community and the La Perouse Local Aboriginal Land Council. </span></em></p><p class="fine-print"><em><span>Sue O'Connor receives funding from The Australian Research Council.</span></em></p>There’s been a long-standing debate over whether dingoes started out wild or domesticated. One thing is clear – they had a close relationship with First Peoples.Loukas Koungoulos, Postdoctoral research fellow, Australian National UniversityJane Balme, Professor Emerita of Archaeology, The University of Western AustraliaShane Ingrey, Postdoctoral research fellow, ARC Centre of Excellence for Australian Biodiversity and Heritage (CABAH), UNSW SydneySue O'Connor, Distinguished Professor, School of Culture, History & Language, Australian National UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2119172023-09-21T02:29:20Z2023-09-21T02:29:20ZCurious Kids: what came first, the chicken or the egg?<figure><img src="https://images.theconversation.com/files/549468/original/file-20230921-15-j14ijn.png?ixlib=rb-1.1.0&rect=92%2C16%2C5497%2C4232&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock/Edited by The Conversation</span></span></figcaption></figure><blockquote>
<p><strong>What came first, the chicken or the egg? — Grace, age 12, Melbourne</strong></p>
</blockquote>
<p><a href="https://theconversation.com/au/topics/curious-kids-36782"><img src="https://images.theconversation.com/files/291898/original/file-20190911-190031-enlxbk.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=90&fit=crop&dpr=1" width="100%"></a></p>
<p>Hi Grace!</p>
<p>Thanks for this great question. It’s an age-old dilemma that has left many people scratching their heads. </p>
<p>From an evolutionary perspective, both answers could be considered true! It all depends on how you interpret the question.</p>
<h2>The case for the egg</h2>
<p>When the first vertebrates – that is, the first animals with backbones – came out of the sea to live on land, they faced a challenge. </p>
<p>Their eggs, similar to those of modern fish, were covered only in a thin layer called a membrane. The eggs would quickly dry up and die when exposed to air. Some animals such as amphibians (the group that includes frogs and axolotls) solved this problem by simply laying their eggs in water – but this limited how far inland they could travel. </p>
<p>It was the early reptiles that evolved a key solution to this problem: an egg with a protective outer shell. The first egg shells would have <a href="https://phys.org/news/2020-06-hard-eggshells-evolved-dinosaur-family.html">been soft and leathery</a> like the eggs of a snake or a sea turtle. Hard-shelled eggs, such as those of birds, likely appeared much later. </p>
<p>Some of the <a href="https://www.nature.com/articles/s41598-019-40604-8">oldest known hard-shelled eggs</a> appear in the fossil record during the Early Jurassic period, roughly 195 million years ago. Dinosaurs laid these eggs, although reptiles such as crocodiles were also <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0171919">producing hard-shelled eggs</a> during the Jurassic.</p>
<p>As we know now, it was a line of dinosaurs that eventually gave rise to the many species of birds we see today, including the chicken. </p>
<p>Chickens belong to an order of birds known as the Galliformes, which includes other ground-dwelling birds such as turkeys, pheasants, peafowl and quails. </p>
<p>Specifically, chickens are part of a galliform genus called <em>Gallus</em>, which is thought to have started changing into its modern species between 6 million and 4 million <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7014787/">years ago in South-East Asia</a>. Domestic chickens only began appearing some time within the <a href="https://www.smithsonianmag.com/smart-news/researchers-pinpoint-date-when-chickens-were-first-domesticated-180980212">past 10,000 years</a>.</p>
<p>This means hard-shelled eggs like the ones chickens lay are older than chickens themselves by almost 200 million years. So problem solved, right? </p>
<p>Well, it’s a matter of perspective.</p>
<h2>The case for the chicken</h2>
<p>If we interpret the question as referring specifically to chicken eggs – and not all eggs – the answer is very different.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/549469/original/file-20230921-24-bdrveo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/549469/original/file-20230921-24-bdrveo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/549469/original/file-20230921-24-bdrveo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/549469/original/file-20230921-24-bdrveo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/549469/original/file-20230921-24-bdrveo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/549469/original/file-20230921-24-bdrveo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/549469/original/file-20230921-24-bdrveo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/549469/original/file-20230921-24-bdrveo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">No fowl play here.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>Unlike most species of animals, the modern chicken didn’t evolve naturally through evolution. Rather, it’s the result of domestication: a process where humans selectively breed animals to create individuals that are more tame and have more desirable traits.</p>
<p>The most famous example is the domestication of wolves into dogs by humans. Wolves and dogs have <a href="https://www.scientificamerican.com/article/how-wolf-became-dog/">almost entirely the same DNA</a>, but are very different in how they look and behave. Dogs came from wolves, and so scientists consider dogs to be a subspecies of wolf.</p>
<p>Similarly, chickens came from a species called the red junglefowl, which is found across Southern and South-East Asia. Researchers think red junglefowl were first drawn to humans thousands of years ago, when <a href="https://www.arch.ox.ac.uk/article/major-new-international-research-reveals-new-evidence-about-when-where-and-how-chickens-were">people started farming</a> rice and other cereal grains. </p>
<p>This closeness then allowed domestication to take place. Over many generations the descendants of these tamed birds became their own subspecies. </p>
<p>Technically, the first chicken would have hatched from the egg of a selectively bred junglefowl. It was only when this chicken matured and started reproducing that the first true chicken eggs were laid.</p>
<h2>So which answer is the better one?</h2>
<p>That’s completely up to you to decide. As is the case with many dilemmas, the whole point of the question is to make you think – not necessarily to come up with the perfect answer. </p>
<p>In this case, evolutionary biology allows us to make an argument for both sides – and that is one of the wonderful things about science.</p><img src="https://counter.theconversation.com/content/211917/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ellen K. Mather 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>Evolutionary biology and the fossil record reveal a great deal about the origins of chickens and eggs.Ellen K. Mather, Adjunct Associate Lecturer in Palaeontology, Flinders UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2118322023-08-25T02:08:55Z2023-08-25T02:08:55ZAn expert’s top 5 reasons why dogs can be considered exceptional animals<p>Dogs are important to a lot of humans, but what makes them so?</p>
<p>Apart from being warm, soft and capable of inspiring our unconditional love, there are a number of unique characteristics that set dogs apart from other animals. </p>
<p>As a dog researcher, animal behaviour consultant and canophile (which means I <em>love</em> dogs), let me share five traits that I think make dogs so special.</p>
<h2>Dogs are hypersocial</h2>
<p>We all know those golden retriever-type dogs that appear absurdly delighted to meet any new social being. It’s hard not to be taken in by their infectious friendliness. These furry, hypersocial creatures have some key genetic differences even to other domestic dogs. </p>
<p>Most fascinatingly, these genetic differences are in the area of the genome <a href="https://www.insidescience.org/news/rare-human-syndrome-may-explain-why-dogs-are-so-friendly">associated</a> with hypersociability in people with a genetic condition called Williams-Beuren syndrome. Although people with this syndrome experience negative health effects, they also tend to be very open, engaging and sociable.</p>
<p>Not all dogs fall into this hypersocial category – but even those that don’t are unusually accepting of unfamiliar people and dogs. </p>
<p>Unlike other social wild canids such as wolves, domestic dogs can quite happily live in harmony with different species, as well as individuals of their own species that aren’t from their family. This is what makes it so easy to slot dogs into our lives.</p>
<h2>Dogs are wired to understand us</h2>
<p>Humans have selectively bred dogs for many generations. And in many cases, we’ve bred them to take direction to help us in a wide variety of jobs – including being companions to us. This has led to domestic dogs being born with an interest in humans. </p>
<p>From an early age, <a href="https://www.sciencedirect.com/science/article/pii/S0960982221006023">puppies are attracted</a> to human faces. While dogs are as co-operative as wolves, they tend to be submissive towards humans and follow our directions – whereas wolves are bolder and more likely to lead when <a href="https://www.pnas.org/doi/10.1073/pnas.1709027114">co-operating with humans</a>. </p>
<p>Dogs also learn to follow our gaze, and show a left-gaze bias when looking at human faces. This means they spend more time looking at the left side of our faces (which would be the right side from our perspective). This bias emerges in several species when they are processing emotional information, which shows that dogs are <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0152393">reading our faces</a> to figure out how we’re feeling.</p>
<p>For a while it was also thought dogs were particularly attentive to human gestures such as pointing – but recent research suggests many domestic species and some wild animal species can also <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7555673/">follow pointing</a>. </p>
<h2>Dogs come in countless shapes and sizes</h2>
<p>No other species comes in such a huge variety of shapes and sizes as domestic dogs. Not even cats or horses display the same diversity. </p>
<p>The largest dogs may be close to 25 times the size of the smallest! Beyond that, we have dogs with drop ears and prick ears and everything in between, tails and no tails, or bob tails, short legs and long legs, long noses and short noses – and a huge variety of coat colours, lengths and textures. </p>
<p>For dogs, this huge variation might mean they have more to learn than other animals when it comes to understanding their own kind. For example, owners of herding breed dogs may find their dog a bit confused, or even defensive, when meeting a very different short-faced breed such as a bulldog.</p>
<p>For us, it means we should appreciate how the size and shape of dogs can influence <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0149403">their behaviour</a> and experiences. For instance, dogs with longer noses have sharper vision, while dogs with a lighter build tend to be more energetic and fearful.</p>
<h2>Dogs form deep emotional bonds</h2>
<p>Domestic dogs have been shown to form attachment bonds with human caregivers that are very similar to those formed between <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0065296">children and parents</a>. </p>
<p>This may partly explain why they can read our <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10426098/">emotional signals</a>, why they become distressed (and try to help us) when <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0231742">we are distressed</a>, and why MRI studies show dogs are happy when they smell <a href="https://www.sciencedirect.com/science/article/pii/S0376635714000473">their owners</a>. </p>
<p>It may also be why they panic when separated from us. Dogs’ attachment to humans goes beyond being hypersocial. To them, we are a lot more than the food we provide and the balls we throw. We are an attachment figure akin to a parent. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/544437/original/file-20230824-15-wnoet.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/544437/original/file-20230824-15-wnoet.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/544437/original/file-20230824-15-wnoet.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/544437/original/file-20230824-15-wnoet.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/544437/original/file-20230824-15-wnoet.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/544437/original/file-20230824-15-wnoet.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/544437/original/file-20230824-15-wnoet.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/544437/original/file-20230824-15-wnoet.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Dogs’ attachment to humans helps explain why they may experience emotional distress when separated from us.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/dogs-can-smell-peoples-stress-new-study-191212">Dogs can smell people's stress – new study</a>
</strong>
</em>
</p>
<hr>
<h2>Dogs can help us be our best selves</h2>
<p>Most dog owners would agree their dog brings out the best in them. They can confide in their dog and love them unconditionally – sometimes more easily than they can another human.</p>
<p>Dogs are playing important roles in animal-assisted therapy, where their nonjudgmental presence can be a calming influence and <a href="https://link.springer.com/article/10.1007/s40489-019-00188-5">facilitate social interactions</a>. They can even help children <a href="https://link.springer.com/article/10.1007/s10643-022-01392-5">learn to read</a> and <a href="https://www.mdpi.com/2077-0383/10/21/5171">alleviate anxiety</a>. </p>
<p>Although assisting humans with their emotional problems can be a difficult task for such an emotionally sensitive species, research suggests the right dogs can rise to the task if their workload is <a href="https://www.sciencedirect.com/science/article/pii/S1558787818302193">managed carefully</a>. </p>
<p>Horses are also used in animal-assisted therapy, as are some smaller furry animals. However, dogs are more portable and can remain at ease in stimulating environments such as courtrooms, schools and airports. They are uniquely placed to accompany us wherever we go.</p>
<h2>Paws for thought</h2>
<p>We might like to think dogs are special for some of the traits we value in humans, such as intelligence, selflessness or a loving nature. But really dogs are exceptional for simply being dogs. </p>
<p>They are social acrobats that can find social harmony wherever they go. They have rich emotional lives in which they co-exist with different species and can even forge bonds <a href="https://www.youtube.com/watch?v=89dCR3VinMM&ab_channel=WCCO-CBSMinnesota">outside of their own species</a>. </p>
<p>They are also generally tolerant of our primate ways – and good at receiving our love. And for me that’s enough.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/544441/original/file-20230824-17-jct3ra.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/544441/original/file-20230824-17-jct3ra.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/544441/original/file-20230824-17-jct3ra.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/544441/original/file-20230824-17-jct3ra.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/544441/original/file-20230824-17-jct3ra.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/544441/original/file-20230824-17-jct3ra.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/544441/original/file-20230824-17-jct3ra.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/544441/original/file-20230824-17-jct3ra.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Dogs are special for all the things that make them who they are.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure><img src="https://counter.theconversation.com/content/211832/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Melissa Starling 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>Dogs have rich emotional lives in which they can coexist with different species, and even forge bonds outside of their own species.Melissa Starling, Postdoctoral Researcher in Veterinary Science, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2089092023-08-03T18:01:18Z2023-08-03T18:01:18ZCats first finagled their way into human hearts and homes thousands of years ago – here’s how<figure><img src="https://images.theconversation.com/files/541015/original/file-20230803-19-fmuwe.jpg?ixlib=rb-1.1.0&rect=10%2C0%2C6647%2C4626&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Who run the world? Cats!</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/black-cat-stretches-on-rug-in-bedroom-royalty-free-image/1402118614">Grace Cary/Moment via Getty Images</a></span></figcaption></figure><p>A few years ago, I had the opportunity to go on safari in southern Africa. One of the greatest thrills was going out at night looking for predators on the prowl: lions, leopards, hyenas.</p>
<p>As we drove through the darkness, though, our spotlight occasionally lit up a smaller hunter – a slender, tawny feline, faintly spotted or striped. The glare would catch the small cat for a moment before it darted back into the shadows.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/540798/original/file-20230802-25-fqa49r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="long-legged, striped cat peeks out of scrubby greens" src="https://images.theconversation.com/files/540798/original/file-20230802-25-fqa49r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/540798/original/file-20230802-25-fqa49r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/540798/original/file-20230802-25-fqa49r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/540798/original/file-20230802-25-fqa49r.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/540798/original/file-20230802-25-fqa49r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1131&fit=crop&dpr=1 754w, https://images.theconversation.com/files/540798/original/file-20230802-25-fqa49r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1131&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/540798/original/file-20230802-25-fqa49r.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"></a>
<figcaption>
<span class="caption">An African wildcat doesn’t look so different from a domestic cat.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/african-wildcat-falbkatze-felis-lybica-african-wild-royalty-free-image/494894455">pum_eva/iStock via Getty Images Plus</a></span>
</figcaption>
</figure>
<p>Based on its size and appearance, I initially presumed it was someone’s pet inexplicably out in the bush. But further scrutiny revealed distinctive features: legs slightly longer than those of most domestic cats, and a striking black-tipped tail. Still, if you saw one from your kitchen window, your first thought would be “Look at that beautiful cat in the backyard,” not “How’d that African wildcat get to New Jersey?”</p>
<p><a href="https://scholar.google.com/citations?user=G4Np3c0AAAAJ&hl=en&oi=ao">As an evolutionary biologist</a>, I’ve spent my career <a href="https://www.jonathanlosos.com/research">studying how species adapt to their environment</a>. My research has been reptile-focused, investigating the workings of <a href="https://www.britannica.com/science/natural-selection">natural selection</a> on lizards.</p>
<p>Yet, I’ve always loved and been fascinated by felines, ever since we adopted a shelter cat when I was 5 years old. And the more I’ve thought about those African wildcats, the more I’ve marveled at their evolutionary success. The species’ claim to fame is simple: The <a href="https://doi.org/10.1126/science.1139518">African wildcat is the ancestor</a> of our beloved household pets. And despite changing very little, their descendants have become among the world’s two most popular companion animals. (Numbers are fuzzy, but the global population of <a href="https://media.nature.com/original/magazine-assets/d41586-018-01018-0/d41586-018-01018-0.pdf">cats</a> and <a href="https://www.wellbeingintlstudiesrepository.org/wbn/vol2/iss5/1/">dogs</a> approaches a billion for each.)</p>
<p>Clearly, the few evolutionary changes the domestic cat has made have been the right ones to wangle their way into people’s hearts and homes. How did they do it? I explored this question in my book “<a href="https://www.penguinrandomhouse.com/books/610619/the-cats-meow-by-jonathan-b-losos/">The Cat’s Meow: How Cats Evolved from the Savanna to Your Sofa</a>.”</p>
<h2>Why the African wildcat?</h2>
<p>Big cats – like lions, tigers and pumas – are the attention-grabbing celebrities of the feline world. But of the <a href="https://en.wikipedia.org/wiki/List_of_felids">41 species of wild felines</a>, the vast majority are about the size of a housecat. Few people have heard of the black-footed cat or the Borneo bay cat, much less the kodkod, oncilla or marbled cat. Clearly, the little-cat side of the feline family needs a better PR agent.</p>
<p>In theory, any of these species could have been the progenitor of the domestic cat, but <a href="https://doi.org/10.1126/science.1139518">recent DNA studies demonstrate unequivocally</a> that today’s housecats arose from the African wildcat – specifically, the North African subspecies, <em>Felis silvestris lybica</em>.</p>
<p>Given the profusion of little pusses, why was the North African wildcat the one to give rise to our household companions?</p>
<p>In short, it was the right species in the right place at the right time. <a href="https://www.britannica.com/place/Mesopotamia-historical-region-Asia">Civilization began</a> in the <a href="https://www.britannica.com/place/Fertile-Crescent">Fertile Crescent</a> about 10,000 years ago, when people first settled into villages and started growing food.</p>
<p>This area – spanning parts of modern-day Egypt, Turkey, Syria, Iran and more – is <a href="https://en.wikipedia.org/wiki/List_of_felids">home to numerous small cats</a>, including the caracal, serval, jungle cat and sand cat. But of these, the African wildcat is the one that to this day enters villages and <a href="https://www.saveacat.org/african-wildcats.html">can be found around humans</a>. </p>
<p>African wildcats are among the friendliest of feline species; raised gently, they <a href="https://www.hachettebookgroup.com/titles/john-bradshaw/cat-sense/9780465064960/">can make affectionate companions</a>. In contrast, despite the most tender attention, their close relative the European wildcat <a href="https://www.hachettebookgroup.com/titles/john-bradshaw/cat-sense/9780465064960/">grows up to be hellaciously mean</a>.</p>
<p>Given these tendencies, it’s easy to <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5790555/">envision what likely happened</a>. People settled down and started raising crops, storing the excess for lean times. These granaries led to rodent population explosions. Some African wildcats – those with the least fear of humans – took advantage of this bounty and started hanging around. People saw the benefit of their presence and treated the cats kindly, perhaps giving them shelter or food. The boldest cats entered huts and perhaps allowed themselves to be petted – kittens are adorable! – and, voilà, the domestic cat was born.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/541018/original/file-20230803-15-fpyrml.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Mummy of a cat wrapped in material with an X-ray image of the skeleton inside" src="https://images.theconversation.com/files/541018/original/file-20230803-15-fpyrml.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/541018/original/file-20230803-15-fpyrml.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=1030&fit=crop&dpr=1 600w, https://images.theconversation.com/files/541018/original/file-20230803-15-fpyrml.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=1030&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/541018/original/file-20230803-15-fpyrml.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=1030&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/541018/original/file-20230803-15-fpyrml.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1294&fit=crop&dpr=1 754w, https://images.theconversation.com/files/541018/original/file-20230803-15-fpyrml.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1294&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/541018/original/file-20230803-15-fpyrml.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1294&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Egyptian mummified cat.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/mummified-cat-from-egypt-dated-2493-bc-news-photo/590674867">Universal History Archive/Universal Images Group via Getty Images</a></span>
</figcaption>
</figure>
<p>Where exactly domestication occurred – if it was a single place and not simultaneously throughout the entire region – is unclear. But <a href="https://mymodernmet.com/cats-in-ancient-egyptian-art/">tomb paintings and sculptures</a> show that by 3,500 years ago, domestic cats lived in Egypt. <a href="https://doi.org/10.1038/s41437-022-00568-4">Genetic analysis</a> – including <a href="https://doi.org/10.1038/s41559-017-0139">DNA from Egyptian cat mummies</a> – and archaeological data chart the feline diaspora. They moved northward through Europe (and ultimately to North America), south deeper into Africa and eastward to Asia. Ancient DNA even demonstrates that <a href="https://doi.org/10.1038/s41559-017-0139">Vikings played a role in spreading felines</a> far and wide.</p>
<h2>What cat traits did domestication emphasize?</h2>
<p>Domestic cats possess many colors, patterns and hair textures not seen in wildcats. Some <a href="https://cfa.org/">cat breeds</a> have distinctive physical features, like <a href="https://www.tica.org/breeds/browse-all-breeds?view=article&id=857:munchkin-breed&catid=79">munchkins’ short legs</a>, <a href="https://cfa.org/siamese/">Siameses’ elongated faces</a> or <a href="https://cfa.org/persian/">Persians’ lack of muzzle</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/541021/original/file-20230803-19-s56je1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="closeup of a fluffy gray cat's face with a flat smooshed face" src="https://images.theconversation.com/files/541021/original/file-20230803-19-s56je1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/541021/original/file-20230803-19-s56je1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=474&fit=crop&dpr=1 600w, https://images.theconversation.com/files/541021/original/file-20230803-19-s56je1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=474&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/541021/original/file-20230803-19-s56je1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=474&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/541021/original/file-20230803-19-s56je1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=595&fit=crop&dpr=1 754w, https://images.theconversation.com/files/541021/original/file-20230803-19-s56je1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=595&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/541021/original/file-20230803-19-s56je1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=595&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 fluffy, flat-faced Persian cat has changed a lot in looks from its wildcat ancestor.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/flossie-a-persian-cat-is-groomed-during-the-shropshire-cat-news-photo/1463247867">Shirlaine Forrest via Getty Images</a></span>
</figcaption>
</figure>
<p>Yet many domestics appear basically indistinguishable from wildcats. In fact, only <a href="https://doi.org/10.1073/pnas.1410083111">13 genes have been changed by natural selection</a> during the domestication process. By contrast, <a href="https://doi.org/10.1038/nature11837">almost three times as many genes changed</a> during the descent of dogs from wolves.</p>
<p>There are only two ways to indisputably identify a wildcat. You can measure the size of its brain – <a href="https://doi.org/10.1007/978-3-642-70877-0_13">housecats</a>, <a href="https://doi.org/10.3998/jar.0521004.0068.201">like other domestic animals</a>, have evolved reductions in the parts of the brain associated with aggression, fear and overall reactivity. Or you can measure the length of its intestines – <a href="https://doi.org/10.1111/j.1439-0469.2009.00537.x">longer in domestic cats</a> to digest vegetable-based food provided by or scavenged from humans.</p>
<p>The most significant evolutionary changes during cat domestication involve their behavior. The common view that domestic cats are aloof loners couldn’t be further from the truth. When lots of domestic cats live together – in places where humans provide copious amounts of food – <a href="https://www.researchgate.net/publication/266757891_Group-living_in_the_Domestic_Cat_Its_Sociobiology_and_Epidemiology">they form social groups very similar to lion prides</a>. Composed of related females, these cats are very friendly – grooming, playing with and lying on top of each other, nursing each other’s kittens, even serving as midwives during birth.</p>
<p>To signal friendly intentions, <a href="https://gwern.net/doc/cat/psychology/2000-bradshaw.pdf">an approaching cat raises its tail straight up</a>, a trait shared with lions and no other feline species. As anyone who has lived with a cat knows, they use this “I want to be friends” message toward people as well, indicating that they include us in their social circle.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/541024/original/file-20230803-29-bnot80.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="orange cat stretches toward tabletop where woman grates cheese" src="https://images.theconversation.com/files/541024/original/file-20230803-29-bnot80.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/541024/original/file-20230803-29-bnot80.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/541024/original/file-20230803-29-bnot80.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/541024/original/file-20230803-29-bnot80.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/541024/original/file-20230803-29-bnot80.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/541024/original/file-20230803-29-bnot80.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/541024/original/file-20230803-29-bnot80.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">Cats use plenty of tools and tricks to get you to hand over what they want.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/ginger-cat-begs-food-in-the-kitchen-while-cooking-royalty-free-image/1219723659">Nail Galiev/iStock via Getty Images Plus</a></span>
</figcaption>
</figure>
<h2>Evolution of a master manipulator</h2>
<p>Household cats are quite vocal to their human companions, using <a href="https://gwern.net/doc/cat/psychology/2003-nicastro.pdf">different meows to communicate different messages</a>. Unlike the tail-up display, however, this is not an example of their treating us as part of their clan. Quite the contrary, <a href="https://gwern.net/doc/cat/psychology/2000-bradshaw.pdf">cats rarely meow to one another</a>.</p>
<p>The sound of these meows has <a href="https://doi.org/10.1037/0735-7036.118.3.287">evolved during domestication</a> to more effectively communicate with us. Listeners rate the wildcat’s call as more urgent and demanding (“Mee‑O‑O‑O‑O‑O‑W!”) compared with the domestic cat’s more pleasing (“MEE‑ow”). Scientists suggest that these shorter, higher-pitched sounds are <a href="https://doi.org/10.1037/0735-7036.118.3.287">more pleasing to our auditory system</a>, perhaps because young humans have high-pitched voices, and domestic cats have evolved accordingly to curry human favor.</p>
<p>Cats similarly <a href="https://doi.org/10.1016/j.cub.2009.05.033">manipulate people with their purrs</a>. When they want something – picture a cat rubbing against your legs in the kitchen while you open a can of wet food – they purr extra loudly. And this purr is not the agreeable thrumming of a content cat, but an insistent chainsaw br-rr-oom demanding attention.</p>
<p>Scientists digitally compared the spectral qualities of the <a href="https://www.sciencedirect.com/science/article/pii/S0960982209011683#app2">two types of purrs</a> and discovered that the major difference is that the insistent purr includes a component very similar to the sound of a human baby crying. People, of course, are <a href="https://doi.org/10.1111/j.1651-2227.2011.02554.x">innately attuned to this sound</a>, and cats have evolved to take advantage of this sensitivity to get our attention.</p>
<p>Of course, that won’t surprise anyone who’s lived with a cat. <a href="https://www.hachettebookgroup.com/titles/john-bradshaw/the-trainable-cat/9780465093717/">Although cats are very trainable</a> – they’re very food motivated – cats usually train us more than we train them. As the old saw goes, “Dogs have owners, cats have staff.”</p><img src="https://counter.theconversation.com/content/208909/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jonathan Losos recently published a book, "The Cat's Meow," on the topic of this essay.</span></em></p>Natural selection changed just 13 genes to separate your Felix and Fluffy from their African wildcat ancestor.Jonathan Losos, William H. Danforth Distinguished University Professor, Arts & Sciences at Washington University in St. LouisLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1845822022-06-22T13:00:08Z2022-06-22T13:00:08ZBefore chickens became food for people, they were regarded as special exotica<figure><img src="https://images.theconversation.com/files/468976/original/file-20220615-23-j1gma.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A modern cockerel with dramatic plumage</span> <span class="attribution"><a class="source" href="https://robertmay.photography/">Robert May, https://robertmay.photography/</a>, <span class="license">Author provided</span></span></figcaption></figure><p>There are more chickens than any other species of bird on the planet. With three chickens for every <a href="https://royalsocietypublishing.org/doi/full/10.1098/rsos.180325">human being</a>, they are a food staple for millions of people around the world. But new research shows chickens were domesticated only <a href="https://www.pnas.org/doi/10.1073/pnas.2121978119">relatively recently</a> and were once <a href="https://doi.org/10.15184/aqy.2021.90">revered</a>. </p>
<p>The question of where chickens come from and how humans have interacted with them over time has eluded us for decades, <a href="https://www.pnas.org/doi/10.1073/pnas.2121978119">until now</a>. For many people it is difficult to think of chickens as anything other than food. But <a href="https://doi.org/10.15184/aqy.2021.90">two new studies</a> are changing our understanding of human-chicken relationships.</p>
<figure class="align-center ">
<img alt="Blue gloved hands hold up chicken bones" src="https://images.theconversation.com/files/468961/original/file-20220615-13-32g7sz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/468961/original/file-20220615-13-32g7sz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=344&fit=crop&dpr=1 600w, https://images.theconversation.com/files/468961/original/file-20220615-13-32g7sz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=344&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/468961/original/file-20220615-13-32g7sz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=344&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/468961/original/file-20220615-13-32g7sz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=432&fit=crop&dpr=1 754w, https://images.theconversation.com/files/468961/original/file-20220615-13-32g7sz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=432&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/468961/original/file-20220615-13-32g7sz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=432&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Ancient and modern samples Photo credit.</span>
<span class="attribution"><span class="source">Jonathan Rees/ Cardiff University</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>One of our new studies <a href="https://theconversation.com/explainer-what-is-radiocarbon-dating-and-how-does-it-work-9690?fbclid=IwAR27t8VvixTt9a3U7H0U4AoimHpJqWWsbrIAXL0g7UcAOyMuez1eu5WVaoE">radiocarbon dated</a> bones from 23 of the earliest proposed chickens in <a href="https://doi.org/10.15184/aqy.2021.90">Europe and northwest Africa</a>, to test their age. By confirming which chickens are actually ancient we get a clearer insight into when they arrived in these areas and how people interacted with them. <a href="https://twitter.com/Estalwin/status/1534325838816104450">Only five</a> specimens corresponded with the dates that archaeologists had previously assigned to them. The other 18 were much more recent than previously thought, sometimes by thousands of years. </p>
<p>Earlier hypotheses, which based their dates on contextual clues such as where these bones had been located and what other artefacts they were found with, suggested that chickens were present in Europe up to 7,000 years ago. But <a href="https://doi.org/10.15184/aqy.2021.90">our results</a> show they were not introduced until around 800 BC (2,800 years ago). This reveals that chickens are a rather recent arrival to Europe, compared to domestic cattle, pigs and sheep which reached Britain around 6,000 years ago. The new dating also suggests that in many locations there was a <a href="https://doi.org/10.15184/aqy.2021.90">time-lag</a> of several hundred years from when chickens were first introduced to an area, to them really being thought of as food.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/470296/original/file-20220622-21-isx7zt.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/470296/original/file-20220622-21-isx7zt.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=534&fit=crop&dpr=1 600w, https://images.theconversation.com/files/470296/original/file-20220622-21-isx7zt.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=534&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/470296/original/file-20220622-21-isx7zt.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=534&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/470296/original/file-20220622-21-isx7zt.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=671&fit=crop&dpr=1 754w, https://images.theconversation.com/files/470296/original/file-20220622-21-isx7zt.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=671&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/470296/original/file-20220622-21-isx7zt.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=671&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Calibrated radiocarbon results for each specimen, with previous proposed dates in brackets.</span>
<span class="attribution"><a class="source" href="https://www.cambridge.org/core/journals/antiquity/article/redefining-the-timing-and-circumstances-of-the-chickens-introduction-to-europe-and-northwest-africa/0797DAA570D51D988B0514C37C2EC534">Antiquity</a>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Many of the <a href="https://doi.org/10.15184/aqy.2021.90">early chickens</a> identified by our radiocarbon dating are complete or almost complete skeletons. In Britain none of the most ancient skeletons show evidence they were butchered for human consumption. They were often <a href="https://onlinelibrary.wiley.com/doi/10.1002/oa.2988">older animals</a>, buried alone in pits. One specimen even had a well-healed leg fracture, indicating human care. She was also still able to lay eggs: she had a substance called medullary bone inside her skeleton which is formed during egg production. </p>
<p>These clues suggest that rather than being considered a source of food, these early arrivals to northern Europe were more likely regarded as <a href="https://www.cardiff.ac.uk/news/view/2628884-chickens-for-life-not-just-for-dinner">special exotica</a>, especially given their small population size at the time. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/470345/original/file-20220622-19-i2kwtv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/470345/original/file-20220622-19-i2kwtv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=259&fit=crop&dpr=1 600w, https://images.theconversation.com/files/470345/original/file-20220622-19-i2kwtv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=259&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/470345/original/file-20220622-19-i2kwtv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=259&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/470345/original/file-20220622-19-i2kwtv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=325&fit=crop&dpr=1 754w, https://images.theconversation.com/files/470345/original/file-20220622-19-i2kwtv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=325&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/470345/original/file-20220622-19-i2kwtv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=325&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Iron Age hen skeleton from Weston Down, England.</span>
<span class="attribution"><span class="source">Julia Best and Grace Clark</span></span>
</figcaption>
</figure>
<p>In some locations shortly after chickens were introduced, we find them buried with humans. A new survey of British Late Iron Age and Roman <a href="https://doi.org/10.15184/aqy.2021.90">burials that contained chickens</a> indicates these burial rites were often gendered: males were buried with cockerels and females with hens. Chickens may have been included in human graves as “psychopomps”, whose role it was to lead human souls to the afterlife. Such a role would have been in keeping with their association with Mercury (the Roman god of communication and travel). Large quantities of cockerels were sacrificed to Mercury at temples such as Uley, Gloucestershire. In other cases, the chickens in graves were a food offering. This is a practice that became more common in Britain through the Roman period. </p>
<p>It is clear that human-chicken relationships were <a href="https://webarchive.nationalarchives.gov.uk/ukgwa/20210802102845/https://ahrc-blog.com/2020/04/10/the-fable-of-britains-easter-animals/">complex</a> and about more than just food for quite some time, <a href="https://fb.watch/dFLKAB2qkT/">even after</a> they started to venture onto the dinner table.</p>
<p>So where did these special birds first come from? </p>
<h2>From the jungle to the fields</h2>
<p>Recent <a href="https://www.nature.com/articles/s41422-020-0349-y">DNA analyses</a> confirmed chickens were domesticated from a subspecies of red jungle fowl called <em>Gallus gallus spadiceus</em> which lived in south or south-east Asia. This would imply chickens were domesticated within this broad region. </p>
<p>Before now, there were three main hypotheses on location and timing. The first places domestication around 4,000 years ago in the <a href="https://agris.fao.org/agris-search/search.do?recordID=US201300589148">Indus Valley</a>. The second argues it happened in <a href="https://www.sciencedirect.com/science/article/abs/pii/0305440388900805">south-east Asia</a> well over 8,000 years ago. The third sees their origins in <a href="https://www.pnas.org/doi/abs/10.1073/pnas.1411882111">northern China</a> 10,000 years ago. </p>
<p>But these theories fail to take into account crucial factors. These include: dating uncertainties, skeletal similarities between chickens and other local wild species, and the broader cultural and environmental context.</p>
<p>In the second new study our team <a href="https://www.pnas.org/doi/epdf/10.1073/pnas.2121978119">reassessed</a> the identification of the species, the domestic status and the dating of the most ancient reported chicken bones from more than 600 archaeological sites across 89 countries, in four continents. We found all three hypotheses are wrong. The oldest bones now confidently assigned to domestic chickens come from the Neolithic site of Ban Non Wat in central Thailand, and date to around 3,500 years ago – much later than previously thought.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/468963/original/file-20220615-26-o4evj0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/468963/original/file-20220615-26-o4evj0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=420&fit=crop&dpr=1 600w, https://images.theconversation.com/files/468963/original/file-20220615-26-o4evj0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=420&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/468963/original/file-20220615-26-o4evj0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=420&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/468963/original/file-20220615-26-o4evj0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=528&fit=crop&dpr=1 754w, https://images.theconversation.com/files/468963/original/file-20220615-26-o4evj0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=528&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/468963/original/file-20220615-26-o4evj0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=528&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">A rooster retracing the footsteps of its ancestor the red jungle fowl.</span>
<span class="attribution"><span class="source">Nikolas Noonan/ Unsplash.com</span>, <span class="license">Author provided</span></span>
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<p>While uncertainty remains about why chickens were domesticated, one thing appears to have drawn chickens and people together: rice. The introduction of dry rice farming in central Thailand coincides with the date of the oldest chicken remains. This suggests the new type of farming may have been a catalyst for the domestication process. </p>
<p>The clearing of the jungle for cereal cultivation would have created a <a href="https://thesiamsociety.org/wp-content/uploads/2020/04/NHBSS_022_1-2n_Collias_EcologyOfTheRedJ.pdf">comfortable environment</a> for the red jungle fowl. Simultaneously, the newly grown rice, along with <a href="https://link.springer.com/article/10.1007/s41826-021-00040-y">millet</a>, would have drawn the wild jungle fowl into close contact with humans, sparking the domestication process, after which their chicken descendants were dispersed across the world with human societies.</p><img src="https://counter.theconversation.com/content/184582/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Julia Best was supported by the AHRC (AH/L006979/1 and AH/N004558/1), by the NERC Radiocarbon Facility (NF/2015/2/5). The work was conducted when she was employed by both Cardiff University and Bournemouth University. </span></em></p><p class="fine-print"><em><span>Ophélie Lebrasseur is affiliated with the Centre for Anthropobiology and Genomics of Toulouse, UMR 5288, CNRS/Université Toulouse III Paul Sabatier, Toulouse, France, and the Instituto Nacional de Antropología y Pensamiento Latinoamericano, Ministry of Culture, Buenos Aires, Argentina. She receives funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement no. 895107.
Part of the work was conducted when Ophélie Lebrasseur was employed by the University of Oxford, where she was supported by the Arts and HumanitiesResearch Council (grant AH/L006979/1) (2014-2017) and the European Research Council(ERC) starting grant (ERC-2013-StG-337574-UNDEAD) (2017-2018).</span></em></p>Why did the chicken cross the globe? A new study has revealed how chickens were domesticated.Julia Best, Lecturer in archaeology, Cardiff UniversityOphélie Lebrasseur, MSCA Research Fellow, Université de Toulouse III – Paul SabatierLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1805362022-04-04T19:59:50Z2022-04-04T19:59:50ZThe hidden world of octopus cities and culture shows why it’s wrong to farm them<figure><img src="https://images.theconversation.com/files/455855/original/file-20220401-25-1le5ts.jpg?ixlib=rb-1.1.0&rect=0%2C38%2C6496%2C4288&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Research shows that octopuses are sentient, emotional creatures.</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/the-hidden-world-of-octopus-cities-and-culture-shows-why-it-s-wrong-to-farm-them" width="100%" height="400"></iframe>
<p>A recently proposed aquaculture octopus farm in the Canary Islands <a href="https://www.bbc.com/news/science-environment-59667645">would raise 3,000 tonnes of octopus a year</a>, which means almost 275,000 individual octopuses will be killed annually.</p>
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Read more:
<a href="https://theconversation.com/octopus-farms-raise-huge-animal-welfare-concerns-and-theyre-unsustainable-too-179134">Octopus farms raise huge animal welfare concerns - and they're unsustainable too</a>
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<p>My research examines animal minds and ethics, and to me, the phrase “octopus culture” brings to mind <a href="https://arstechnica.com/science/2017/09/why-octopuses-are-building-small-cities-off-the-coast-of-australia/">Octopolis and Octlantis</a>, two communities of wild octopuses in Jarvis Bay, Australia. </p>
<p>In Octopolis, numerous octopuses share — and fight over — a few square metres of seabed. In these watery towns, octopuses form dominance hierarchies, and they’ve started developing new behaviours: male octopuses fight over territory and, perhaps, females by <a href="https://www.newscientist.com/article/dn28085-octopuses-seen-throwing-things-may-be-using-shells-as-weapons/">throwing debris at one another</a> and <a href="https://metazoan.net/15-panocticon/">boxing</a>.</p>
<h2>Octopus community-building</h2>
<p>The discovery of octopus communities came as a surprise to biologists who have long described octopuses as solitary animals that interact with others in three specific contexts: <a href="https://doi.org/10.51291/2377-7478.1370">hunting, avoiding being hunted and mating</a>. </p>
<p>What Octopolis suggests can happen in the wild is what has also been observed in captive octopuses: when living in an overly dense captive environment, <a href="https://doi.org/10.51291/2377-7478.1370">octopuses will form dominance hierarchies</a>. </p>
<p>In their fights for power, male octopuses perform <a href="https://metazoan.net/33-octopus-signals/">an array of antagonistic behaviours</a>, including throwing scallop shells to defend their den, and the “mantle up” display which makes an octopus look like a <a href="https://metazoan.net/wp-content/uploads/2016/01/Nosferatu-from-sst-1.jpg">menacing vampire</a>. Submissive octopuses signal their compliance with light colours and flattened body postures. For their efforts, the dominants appear to gain better access to high-quality dens and to females.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/CaKx1PzejHs?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">A look into the social life of octopus by Australian philosopher Peter Godfrey-Smith.</span></figcaption>
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<h2>Animal culture</h2>
<p>What is going on in Octopolis and Octlantis is properly called octopus culture. The idea of <a href="https://doi.org/10.1007/978-1-4419-1428-6_745">animal culture</a> emerged after scientists noticed that in some groups, animals perform actions that aren’t seen in other groups of the same species.</p>
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Read more:
<a href="https://theconversation.com/did-they-mean-to-do-that-accident-and-intent-in-an-octopuses-garden-85462">Did they mean to do that? Accident and intent in an octopuses' garden</a>
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<p>One of the earliest proponents of animal cultures was the Japanese primatologist <a href="https://www.routledge.com/A-Japanese-View-of-Nature-The-World-of-Living-Things-by-Kinji-Imanishi/Imanishi-Asquith/p/book/9780700716326">Kinji Imanishi</a> who in the 1950s observed that <a href="https://youtu.be/H88M3Av9q-w">a group of Japanese macaques on Koshima Island would wash sweet potatoes in the water before eating them</a>. </p>
<p>This was a new behaviour, not seen in other macaque groups, and observers were lucky enough to observe its origins. A monkey named Imo was the first to wash a potato in the salty water and others soon copied her, leading to a community-wide behaviour pattern. </p>
<p>The idea of animal culture drove much subsequent Japanese primatology, but in Europe and North America culture didn’t get much attention until 1999, when an article <a href="https://doi.org/10.1038/21415">about culture in chimpanzees was published</a>. Since then, evidence of culture — group-typical behaviours that are socially learned — has been found <a href="https://www.ciaoamico.it/pdf/culturaAnimale.pdf">all across the animal kingdom, including among fish, birds and insects</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/455862/original/file-20220401-22-7vgvv6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="a group of japanese macaques in a steamy lake surrounded by snow" src="https://images.theconversation.com/files/455862/original/file-20220401-22-7vgvv6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/455862/original/file-20220401-22-7vgvv6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/455862/original/file-20220401-22-7vgvv6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/455862/original/file-20220401-22-7vgvv6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/455862/original/file-20220401-22-7vgvv6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/455862/original/file-20220401-22-7vgvv6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/455862/original/file-20220401-22-7vgvv6.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">Japanese macaques exhibited social behaviour and influenced a cultural approach to primatology that later extended to other macaques.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
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<h2>A new kind of octopus</h2>
<p>The proposal to start an octopus farm is a proposal to create a new octopus culture, because when cultural animals are brought together, they can’t help but create society. It’s also a proposal to create a new kind of octopus: the cultural behaviours coupled with the captive environment will be a novel environmental niche that shapes subsequent evolution.</p>
<p>Our familiar farmed animals — like Angus cows and Chocktaw hogs — <a href="https://www.nationalgeographic.com/animals/article/domesticated-animals">have been domesticated</a> and are entirely different from the animals they evolved from. </p>
<p>Many of our domesticated animals cannot survive without human care. Examples include <a href="https://www.thesprucepets.com/domesticated-rabbits-in-the-wild-1835750">domestic rabbits</a>, that have evolved without the instincts and colouring wild rabbits have to protect them from predators, <a href="https://www.theguardian.com/australia-news/2021/feb/25/mammoth-woolly-baarack-the-overgrown-sheep-shorn-of-his-35kg-fleece">sheep whose wool grows too thick without regular trimming</a> and <a href="https://www.wired.com/2008/02/chickens-cant-w/">chickens bred for meat that can’t walk as adults because their breasts are too heavy</a>.</p>
<p>Starting an octopus farm is a commitment to creating a new kind of animal that relies on humans for its existence. It isn’t an idea to be taken up lightly, or a project that can responsibly be attempted and then discarded when it turns out to be too difficult or not profitable. </p>
<h2>Managing octopus populations</h2>
<p>There are many reasons to worry that an octopus farm will not be easy to manage. Unlike other farmed animals, octopuses need their space. Octopolis is already a battleground of boxing octopuses; one can only wonder what that will look like on a scale of thousands. </p>
<p>Octopuses are sentient — they are <a href="https://doi.org/10.1126/science.abo2378">emotional animals that feel pain</a>. A recent report commissioned by the <a href="https://www.gov.uk/government/organisations/department-for-environment-food-rural-affairs">department for Environment, Food & Rural Affairs in the United Kingdom</a> reviewed the scientific evidence for pain experience in cephalopod molluscs (octopuses, squid and cuttlefish). </p>
<p>Sentient animals used for food are protected under welfare laws and killed in ways that should minimize their pain. Current methods of slaughtering octopuses include clubbing, slicing open the brain or suffocating them. The report’s authors conclude that none of these methods of slaughter are humane <a href="https://www.lse.ac.uk/News/News-Assets/PDFs/2021/Sentience-in-Cephalopod-Molluscs-and-Decapod-Crustaceans-Final-Report-November-2021.pdf">and recommend against octopus farming</a>. </p>
<p>Octopuses are <a href="https://www.theguardian.com/world/2016/apr/13/the-great-escape-inky-the-octopus-legs-it-to-freedom-from-new-zealand-aquarium">escape artists</a>. The kind of housing needed to shelter them will be difficult to achieve, especially while also providing enrichment, since an enriched environment will be one full of possible getaway routes.</p>
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<a href="https://images.theconversation.com/files/455863/original/file-20220401-21-rfq621.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="an octopus pressed against the glass of an aquarium display tank" src="https://images.theconversation.com/files/455863/original/file-20220401-21-rfq621.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/455863/original/file-20220401-21-rfq621.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=436&fit=crop&dpr=1 600w, https://images.theconversation.com/files/455863/original/file-20220401-21-rfq621.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=436&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/455863/original/file-20220401-21-rfq621.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=436&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/455863/original/file-20220401-21-rfq621.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=548&fit=crop&dpr=1 754w, https://images.theconversation.com/files/455863/original/file-20220401-21-rfq621.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=548&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/455863/original/file-20220401-21-rfq621.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=548&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">Octopus are known for their ability to escape tanks.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
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<p>If an octopus farm is started, and then abandoned, the thousands of domesticated cultural octopuses cannot be released into the sea and be expected to flourish. We learned from the many expensive attempts to release Keiko, the killer whale that starred in the <a href="https://www.imdb.com/title/tt0106965/"><em>Free Willy</em> franchise</a>, that successful reintroduction of captive cultural animals into the wild is not easy. Even after spending US$20 million, <a href="https://www.seattletimes.com/seattle-news/the-20m-lessons-of-freeing-keiko-the-whale/">Keiko died in captivity</a>.</p>
<p>The proposal to bring thousands of animals together into an octopus megacity would scale octopus culture far beyond anything found in nature or in captivity. It would create hundreds of thousands of Keikos, aquatic cultural animals captured from the wild and brought into captivity. And it would force them to live together and create a new culture in what is sure to be a violent octopus slum. </p>
<p>Just now, we are learning that octopuses <a href="https://www.scientificamerican.com/article/octopus-teachers-demonstrate-they-feel-emotional-pain/">feel emotions</a> and have culture, and we are starting to <a href="https://time.com/5819801/rethink-industrialized-farming-next-pandemic/">rethink current practices of intensive animal farming</a>. </p>
<p>It is exactly the wrong moment to propose such a scheme. We now know better.</p><img src="https://counter.theconversation.com/content/180536/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kristin Andrews receives funding from SSHRC, Templeton World Charity Foundation, and York University. She is on the Board of Directors for Borneo Orangutan Society Canada. </span></em></p>Octopus build cities, establish hierarchies and show social group behaviours. Domesticating will mean creating a new kind of octopus, with ecological and ethical implications.Kristin Andrews, Professor, Philosophy, York University, CanadaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1516152020-12-08T00:10:51Z2020-12-08T00:10:51ZWe found algae-farming fish that domesticate tiny shrimp to help run their farms<figure><img src="https://images.theconversation.com/files/373457/original/file-20201207-19-w5awdq.png?ixlib=rb-1.1.0&rect=0%2C2%2C1579%2C880&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Longfin damselfish (left) have domesticated mysid shrimps (right).</span> <span class="attribution"><span class="source">Rohan Brooker</span>, <span class="license">Author provided</span></span></figcaption></figure><p>Humans are experts at domesticating other species and our world would be unrecognisable without it. There would be no cities, no supermarkets, and no pets. Domestication is a special kind of cooperative relationship, where one species provides prolonged support in exchange for a predictable resource.</p>
<p>While humans have domesticated various plants and animals, these relationships are surprisingly rare in other species. It’s true some insects (ants, beetles, and termites among them) domesticate fungi, but few other examples exist outside the insect world.</p>
<p>In <a href="https://www.nature.com/articles/s41467-020-19958-5">our new study</a>, we describe what appears to be first example of a non-human vertebrate domesticating another animal. </p>
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<a href="https://images.theconversation.com/files/373464/original/file-20201207-72125-121b6ld.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Reef in Belize" src="https://images.theconversation.com/files/373464/original/file-20201207-72125-121b6ld.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/373464/original/file-20201207-72125-121b6ld.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/373464/original/file-20201207-72125-121b6ld.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/373464/original/file-20201207-72125-121b6ld.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/373464/original/file-20201207-72125-121b6ld.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/373464/original/file-20201207-72125-121b6ld.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/373464/original/file-20201207-72125-121b6ld.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>
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<span class="caption">On the coral reefs off the coast of Belize, in Central America, longfin damselfish create, manage and feed from algae farms.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/w/index.php?curid=25009448">By Andy Blackledge - P4120130, CC BY 2.0</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
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Read more:
<a href="https://theconversation.com/listen-up-many-farmed-fish-are-hard-of-hearing-heres-why-it-matters-58587">Listen up: many farmed fish are hard of hearing – here's why it matters</a>
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<h2>Farming fish domesticate shrimps</h2>
<p>On the coral reefs off the coast of Belize, in Central America, longfin damselfish create, manage and feed from algae farms. We noticed they regularly have “swarms” of tiny crustaceans called mysid shrimps floating above their farms.</p>
<p>We found this unusual, as most farming damselfishes chase away anything that ventures near their farm. We were unsure why these species associated with one another, so we decided to try to find out what was going on.</p>
<p>First, to see whether mysid shrimps and farming damselfish are regularly found together, we ran a series of what’s known as “<a href="https://www.bbc.co.uk/bitesize/guides/zmxbkqt/revision/5#:%7E:text=A%20transect%20is%20a%20line,and%20recorded%20at%20regular%20intervals.">transects</a>”. In other words, we conducted a series of 30 metre swims along the reef, and during each one we recorded each time we saw mysid shrimps, as well as whether they were near farming damselfish or other fish species. </p>
<p>We found these mysids were far more likely to be found near farming species, like the longfin damselfish, than other species.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/373405/original/file-20201207-17-1nb998r.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/373405/original/file-20201207-17-1nb998r.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/373405/original/file-20201207-17-1nb998r.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/373405/original/file-20201207-17-1nb998r.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/373405/original/file-20201207-17-1nb998r.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/373405/original/file-20201207-17-1nb998r.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/373405/original/file-20201207-17-1nb998r.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">
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<span class="caption">The Smithsonian’s Carrie Bow Cay Marine Research Station off the coast of Belize.</span>
<span class="attribution"><span class="source">Rohan Brooker</span></span>
</figcaption>
</figure>
<p>Next, we wanted to know if the mysids specifically seek out their damselfish partners. </p>
<p>So, we collected mysid shrimps from the field, brought them into the lab and exposed the mysids to water soaked with different things. For example, do they avoid the smell of a predator? Are they attracted to the smell of a farming damselfish? </p>
<p>We found the mysids shrimps were attracted to the longfin damselfish, repulsed by a predator and indifferent towards a non-farming fish — and to the farm itself. </p>
<h2>I help you, you help me</h2>
<p>Many fish eat mysid shrimps, so we ran an experiment to see if longfin damselfish provided protection to the mysids when they are in the fish’s farm. </p>
<p>To do this, we placed mysid shrimps in a clear plastic bag and placed the bag either inside or outside a farm. </p>
<p>We found that when placed outside a farm, other fish tried to eat the mysid shrimps. When inside the farms, any fish that tried to come close to the bag was chased off by the longfin damselfish. This suggested the mysids seek out longfin damselfish, as they provide mysids with protection from predators.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/373410/original/file-20201207-17-3rlho2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Slippery Dick Wrasse is a common predator of shrimps." src="https://images.theconversation.com/files/373410/original/file-20201207-17-3rlho2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/373410/original/file-20201207-17-3rlho2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=374&fit=crop&dpr=1 600w, https://images.theconversation.com/files/373410/original/file-20201207-17-3rlho2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=374&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/373410/original/file-20201207-17-3rlho2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=374&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/373410/original/file-20201207-17-3rlho2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=470&fit=crop&dpr=1 754w, https://images.theconversation.com/files/373410/original/file-20201207-17-3rlho2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=470&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/373410/original/file-20201207-17-3rlho2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=470&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Slippery Dick Wrasse is a common predator of mysid shrimps.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/19731486@N07/3782286043">Brian Gratwicke/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>One question remained: do the mysid shrimps provide a benefit to the longfin damselfish? </p>
<p>Given the damselfish eat the algae they farm, we thought maybe by hovering above the farm, the mysid shrimps waste might act as fertiliser. </p>
<p>To test this, we examined the quality of the algae within farms that did, or did not have mysid shrimps. We also examined the body condition of fish that did, or did not, have mysid shrimps within their farms. </p>
<p>We found farms with shrimps had higher quality algae, and fish from farms with mysid shrimps were in better condition.</p>
<h2>Insight into how domestication happens</h2>
<p>These different analyses together suggest longfin damselfish have domesticated mysid shrimps. The longfin damselfish provide a safe refuge, and in exchange the mysid shrimps provide the damselfish with fertiliser for its farm. </p>
<p>This relationship is important, because while fantastic research has provided insight into the history of domestication in our ancestors, these things happened in the distant past.</p>
<p>In the longfin damselfish, we can watch the early stages of domestication occur as it’s happening. </p>
<p>This is fascinating because it’s very similar to the proposed series of events that led to our domestication of species such as chickens, cats, dogs and pigs. </p>
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Read more:
<a href="https://theconversation.com/it-might-be-the-worlds-biggest-ocean-but-the-mighty-pacific-is-in-peril-150745">It might be the world's biggest ocean, but the mighty Pacific is in peril</a>
</strong>
</em>
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<img src="https://counter.theconversation.com/content/151615/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>William Feeney receives funding from Griffith University and the Alexander von Humboldt Foundation. </span></em></p><p class="fine-print"><em><span>Rohan Brooker received funding from Deakin University and the National Geographic Society. </span></em></p>While humans domesticate plants and animals, these relationships are surprisingly rare in other species. Our new study found a species of fish that appears to have domesticated a kind of tiny shrimp.William Feeney, Postdoctoral Research Fellow in Evolutionary Ecology, Griffith UniversityRohan Brooker, Casual Research Fellow, Deakin UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1318312020-03-02T20:38:31Z2020-03-02T20:38:31ZHumans domesticated horses – new tech could help archaeologists figure out where and when<figure><img src="https://images.theconversation.com/files/317952/original/file-20200302-57541-1t03zoe.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C1305%2C953&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Archaeologists investigate an ancient habitation site in western Mongolia, seeking clues to the early history of domestic horses.</span> <span class="attribution"><span class="source">William Taylor</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>In the increasingly urbanized world, few people still ride horses for reasons beyond sport or leisure. However, on horseback, people, goods and ideas moved across vast distances, shaping the <a href="https://www.sciencemag.org/news/2017/11/how-taming-cows-and-horses-sparked-inequality-across-ancient-world">power structures and social systems</a> of the premechanized era. From the trade routes of the Silk Road or the great Mongol Empire to the equestrian nations of the American Great Plains, horses were the engines of the ancient world.</p>
<p>Where, when and how did humans first domesticate horses?</p>
<p>Tracing the origins of horse domestication in the prehistoric era has proven to be an exceedingly difficult task. Horses – and the people who care for them – tend to live in remote, dry or cold grassland regions, moving often and leaving only ephemeral marks in the archaeological record. In the steppes, pampas and plains of the world, historic records are often ambiguous or absent, archaeological sites are poorly investigated and research is published in a variety languages.</p>
<p>At the heart of the issue is a more basic struggle: How can you distinguish a “domestic” animal from its wild cousin? What does it even mean to be “domesticated”? And can scientists trace this process in archaeological sites that are thousands of years old and often consist of nothing more than piles of discarded bones? </p>
<p><a href="https://scholar.google.com/citations?hl=en&user=mlo_aD8AAAAJ">As an archaeozoologist, I work in a field</a> that seeks to develop ways to do just this – and with the aid of new technologies, recent research is turning up some surprising answers.</p>
<h2>Looking for traces of domestication</h2>
<p>Analyzing horse bones from archaeological sites across Eurasia, 20th-century scholars argued over whether changes in the size and shape of horse bones might reflect the impacts of human control. They debated whether management of a domestic herd would leave recognizable patterns in the ages and sex of horses in the archaeological record.</p>
<p>Without agreed-upon criteria for how to recognize horse domestication in the archaeological record, a staggering range of different ideas emerged.</p>
<p>In nearly every corner of the world with grassland ecosystems and wild horses, various researchers hypothesized domestication began in Anatolia, Iberia, China and even North America. Some more outlandish models suggested an origin for horse domestication <a href="https://www.jstor.org/stable/124404">as far back as the last Ice Age</a>, about 20,000 years ago. </p>
<p>Toward the end of the 20th century, a key breakthrough in the debate came when researchers recognized that the use of bridle mouthpieces, known as a “bit,” can cause unique damage to the teeth of a horse, known as “bit wear.”</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/317951/original/file-20200302-57517-1muwfsw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/317951/original/file-20200302-57517-1muwfsw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/317951/original/file-20200302-57517-1muwfsw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/317951/original/file-20200302-57517-1muwfsw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/317951/original/file-20200302-57517-1muwfsw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/317951/original/file-20200302-57517-1muwfsw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/317951/original/file-20200302-57517-1muwfsw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/317951/original/file-20200302-57517-1muwfsw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=565&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Horse teeth exhibiting damage to the front of the second premolar, caused by a metal mouthpiece – known as ‘bit wear.’</span>
<span class="attribution"><span class="source">William Taylor</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Still the complicated nature of archaeological data has made the search for horse domestication a process of trial and error. For example, one famous horse with bit wear, from the site of Derievka in Ukraine, seemed to place horse domestication in Eastern Europe <a href="https://www.latimes.com/archives/la-xpm-1995-03-14-wr-42503-story.html">as early as around 4000 B.C.</a> – until scientific dating showed that this animal lived around 600 B.C. </p>
<h2>Evidence from Kazakhstan</h2>
<p>In the late 2000s, a proliferation of scientific research seemed to narrow the field to a single, compelling answer for the first domestication of the horse.</p>
<p>Researchers zeroed in on <a href="https://www.researchgate.net/publication/281350504_Early_horse_domestication_on_the_Eurasian_steppe">a site called Botai</a>, in northern Kazakhstan, dating back to around 5,500 years ago. Nearly 100% of the animal bones they identified there were from horses. These animals were butchered and eaten, and their bones were used to make a variety of tools. Some were buried in ritual pits.</p>
<p>Initially, skeptics argued that the age and sex patterns of Botai horses were inconsistent with a domestic herd. Pastoral management involves culling young, mostly male animals, and far too many of these remains were from adults and females. </p>
<p>However, individual teeth found at Botai showed apparent bit wear. And, in a dramatic discovery made in 2009, a new technique that analyzes ancient fat residues suggested that the ceramic vessels recovered at Botai <a href="https://doi.org/10.1126/science.1168594">once contained horse milk products</a>. If true, that finding would indicate humans had raised and cared for the horses that produced it. </p>
<p>This new biomolecular evidence appeared to place horse domestication deep into the past, around 3500 B.C. To some, if people were eating and milking horses, logic dictated that they must have also ridden them. </p>
<p>Many researchers took this thinking a step further, using this early timeline to argue that horse domestication kicked off the <a href="https://press.princeton.edu/books/paperback/9780691148182/the-horse-the-wheel-and-language">continent-wide dispersal of Indo-European peoples and language groups</a> around five or six thousand years ago. </p>
<h2>Newer techniques cast doubt on Botai</h2>
<p>As the 2020s begin, the pace of <a href="https://theconversation.com/archaeological-discoveries-are-happening-faster-than-ever-before-helping-refine-the-human-story-128743">technological innovation in archaeology</a> continues to accelerate. And new archaeological data have begun to trickle in from understudied areas.</p>
<p>With improving methods, new information has triggered serious doubts about the Botai/Indo-European model about domestication.</p>
<p>In a shocking 2018 study, a French research team revealed that the horses of Botai were in fact not the domestic horse (<em>Equus caballus</em>) at all, <a href="https://doi.org/10.1126/science.aao3297">but instead <em>Equus przewalskii</em></a> – the Przewalski’s horse, a wild animal with no documented evidence of management by human societies.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/317950/original/file-20200302-57512-aj8ppb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/317950/original/file-20200302-57512-aj8ppb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/317950/original/file-20200302-57512-aj8ppb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=473&fit=crop&dpr=1 600w, https://images.theconversation.com/files/317950/original/file-20200302-57512-aj8ppb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=473&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/317950/original/file-20200302-57512-aj8ppb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=473&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/317950/original/file-20200302-57512-aj8ppb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=595&fit=crop&dpr=1 754w, https://images.theconversation.com/files/317950/original/file-20200302-57512-aj8ppb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=595&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/317950/original/file-20200302-57512-aj8ppb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=595&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 family of wild Przewalski’s horses at sunset in Khustai National Park, Mongolia, where they have been reintroduced following their near-extinction.</span>
<span class="attribution"><span class="source">William Taylor</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Another project using ancient DNA analysis of human remains from Botai showed <a href="https://www.sciencemag.org/news/2018/05/these-asian-hunter-gatherers-may-have-been-first-people-domesticate-horses">no genetic links between the area’s ancient residents and Indo-European groups</a>, undermining the idea that horse domestication at Botai stimulated a continental dispersal on horseback.</p>
<p>In the ensuing chaos, researchers must now find a way to piece together the horse’s story, and find an explanation that fits these new facts.</p>
<p>Some, including the equine DNA researchers who published the new discoveries, now suggest that Botai represents a <a href="https://www.sciencemag.org/news/2018/02/ancient-dna-upends-horse-family-tree">separate, failed domestication event of Przewalski’s horse</a>.</p>
<p>Other scholars now seek to reevaluate the archaeological and historical records around the horse’s initial domestication with a more skeptical eye. </p>
<p>As of the writing of this story, the oldest clearly identified remains of the modern domestic horse, <em>Equus caballus</em>, date back only as far as about 2000 B.C. – to the chariot burials of Russia and Central Asia. From here, researchers are scrambling backwards in time, seeking to find the “big bang” of the human-horse relationship.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/318141/original/file-20200302-18303-8dxwf5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/318141/original/file-20200302-18303-8dxwf5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/318141/original/file-20200302-18303-8dxwf5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=388&fit=crop&dpr=1 600w, https://images.theconversation.com/files/318141/original/file-20200302-18303-8dxwf5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=388&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/318141/original/file-20200302-18303-8dxwf5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=388&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/318141/original/file-20200302-18303-8dxwf5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=488&fit=crop&dpr=1 754w, https://images.theconversation.com/files/318141/original/file-20200302-18303-8dxwf5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=488&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/318141/original/file-20200302-18303-8dxwf5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=488&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Pastoral herding is still a key way of life in Mongolia, and horses are important as both livestock and transportation.</span>
<span class="attribution"><a class="source" href="https://www.facebook.com/OrsooBayarsaikhanPhotography/">Orsoo Bayarsaikhan Photography</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>No clear answers, but a path forward</h2>
<p>New data from places typically left out of the conversation, such as Mongolia, may help fill the holes in the story of horse domestication. </p>
<p>My colleagues and I, led by <a href="https://scholar.google.com/citations?user=vi30G9cAAAAJ&hl=en&oi=ao">Shevan Wilkin</a>, recently recovered ancient proteins from the teeth of Mongolia’s ancient herders that suggest these pastoralists who lived around 3000 B.C. <a href="https://doi.org/10.1038/s41559-020-1120-y">drank the milk of cattle or sheep or goats</a> – with no evidence they drank milk from horses.</p>
<p>In fact, much of Central Asia may not have had domestic horses at all until well after 2000 B.C. Another recent study suggests the late second millennium B.C. saw a spike in the frequency of domestic horses <a href="https://doi.org/10.1038/s41598-020-57735-y">across the continent</a> – perhaps because the innovation of horseback riding occurred much later than researchers had commonly assumed. </p>
<p>The urgent question now becomes: Where did the first ancestors of the modern domestic horse first find themselves under human care? And what does this tell researchers about the rest of human history that followed?</p>
<p>In the decades to come, the story of humans and horses is likely to be dramatically rewritten – maybe more than once.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/318140/original/file-20200302-18303-1q59bl4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/318140/original/file-20200302-18303-1q59bl4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/318140/original/file-20200302-18303-1q59bl4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/318140/original/file-20200302-18303-1q59bl4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/318140/original/file-20200302-18303-1q59bl4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/318140/original/file-20200302-18303-1q59bl4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/318140/original/file-20200302-18303-1q59bl4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/318140/original/file-20200302-18303-1q59bl4.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 work to extract collagen at the Max Planck Institute for the Science of Human History in Jena, Germany, to identify ancient horse bones from Central Asia for DNA analysis.</span>
<span class="attribution"><span class="source">William Taylor</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Archaeologists must continue to use cutting-edge technology, constantly reevaluating old conclusions developed with earlier techniques. DNA and biomolecular data must be paired with other kinds of information, such as skeletal clues, that can tell us <a href="https://www.smithsonianmag.com/smithsonian-institution/how-dan-zebra-stopped-ill-fated-governent-breeding-program-tracks-180973542/">how horses were bridled, exerted or cared for</a>. That can help to distinguish wild horses from early domestic horses managed by humans.</p>
<p>Species identifications from archaeological sites must be made using DNA rather than assumed (as at Botai) – and each specimen must be directly radiocarbon dated to determine its age, rather than lumped in with other similar objects and dated through guesswork (as at Derievka). </p>
<p>Most importantly, archaeologists must continue to dive deeper into the archaeological record of the desert and grassland regions of the Old World – Eastern Europe, Russia, Central Asia, Mongolia and elsewhere – where the secrets of the past have not yet all been brought to light.</p>
<p>[<em>You’re smart and curious about the world. So are The Conversation’s authors and editors.</em> <a href="https://theconversation.com/us/newsletters/weekly-highlights-61?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=weeklysmart">You can get our highlights each weekend</a>.]</p><img src="https://counter.theconversation.com/content/131831/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>William Taylor receives funding from the National Science Foundation, the Fulbright Program, National Geographic, the Germanic Academic Exchange (DAAD), and the Max Planck Institute for the Science of Human History. </span></em></p>Archaeologists have long argued over when and how people first domesticated horses. A decade ago, new techniques appeared to have provided answers – but further discoveries change the story again.William Taylor, Assistant Professor and Curator of Archaeology, University of Colorado BoulderLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1300412020-01-30T13:13:31Z2020-01-30T13:13:31ZModern tomatoes are very different from their wild ancestors – and we found missing links in their evolution<figure><img src="https://images.theconversation.com/files/312304/original/file-20200128-81416-1odt8n2.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C5000%2C2971&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Tomatoes' ancestors looked very different.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/flatlay-fresh-colorful-ripe-fall-summer-1124959727"> Foxys Forest Manufacture/Shutterstock</a></span></figcaption></figure><p><em>The Research Brief is a short take on interesting academic work.</em></p>
<p><strong>The Big Idea:</strong> The tomato’s path from wild plant to household staple is much more complex than researchers have long thought. For many years, scientists believed that humans domesticated the tomato in two major phases. First, native people in South America cultivated blueberry-sized wild tomatoes about 7,000 years ago to breed a plant with a cherry-sized fruit. Later, people in <a href="https://en.wikipedia.org/wiki/Mesoamerica">Mesoamerica</a> bred this intermediate group further to form the large cultivated tomatoes that we eat today. </p>
<p>But in a 2020 study, we show that the cherry-sized tomato likely <a href="https://doi.org/10.1093/molbev/msz297">originated in Ecuador around 80,000 years ago</a>. No human groups were domesticating plants that long ago, so this implies that it started as a wild species, although people in Peru and Ecuador probably cultivated it later. </p>
<p>We also found that two subgroups from this intermediate group spread northward to Central America and Mexico, possibly as weedy companions to other crops. As this happened, their fruit traits changed radically. They came to look more like wild plants, with smaller fruits than their South American counterparts and higher levels of citric acid and beta carotene. </p>
<p>We were surprised to find that modern cultivated tomatoes seem most closely related to this wild-like tomato group, which is still found in Mexico, although farmers don’t deliberately cultivate it. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/312295/original/file-20200128-81341-1aqkfhm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/312295/original/file-20200128-81341-1aqkfhm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/312295/original/file-20200128-81341-1aqkfhm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=109&fit=crop&dpr=1 600w, https://images.theconversation.com/files/312295/original/file-20200128-81341-1aqkfhm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=109&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/312295/original/file-20200128-81341-1aqkfhm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=109&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/312295/original/file-20200128-81341-1aqkfhm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=137&fit=crop&dpr=1 754w, https://images.theconversation.com/files/312295/original/file-20200128-81341-1aqkfhm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=137&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/312295/original/file-20200128-81341-1aqkfhm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=137&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Average fruit size in the cultivated tomato in comparison with its semi-domesticated and fully wild relatives.</span>
<span class="attribution"><span class="source">Hamid Razifard</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p><strong>Why it matters:</strong> This research has direct implications for crop improvement. For example, some intermediate tomato groups have high levels of glucose, which makes the fruit sweeter. Breeders could use those plants to make cultivated tomatoes more attractive to consumers. </p>
<p>We also saw signals that some varieties in this intermediate group had traits that promoted disease resistance and drought tolerance. Those plants could be used to breed hardier tomatoes.</p>
<p><strong>What still isn’t known:</strong> We don’t know how the intermediate group of tomatoes spread from South America to Central America and Mexico. Birds may have eaten the fruits and excreted the seeds elsewhere, or humans may have cultivated or traded them.</p>
<p>Another question is why this intermediate group “regressed” and lost so many domestication traits once it spread north. Natural selection in new northern habitats may have actively favored tomatoes with more wild-like traits. It also could be that humans weren’t breeding these plants and selecting for domestication traits, such as large fruits, which may require plants to use more energy than they would put into fruiting naturally.</p>
<p><strong>How we do our work:</strong> We <a href="https://scholar.google.com/citations?user=tNvKhWwAAAAJ&hl=en">reconstruct tomato history</a> by <a href="https://scholar.google.com/citations?user=E_vnipYAAAAJ&hl=en">sequencing the genomes</a> of wild, intermediate and domesticated tomato varieties. We also carry out population genomic analyses, in which we use models and statistics to deduce the changes that have occurred to tomatoes over time.</p>
<p>This work involves writing a lot of computer codes to analyze large amounts of data and look at patterns of variation in DNA sequences. We also work with other scientists to grow tomato samples and record data on many traits, such as fruit size, sugar content, acid content and flavor compounds. </p>
<p><strong>What else is happening in the field:</strong> Feeding a growing human population will require improving crop yields and quality. To do this, scientists need to know more about plant genes that are involved in phenomena such as fruit development and flavor and disease resistance. </p>
<p>For example, research led by <a href="http://lippmanlab.labsites.cshl.edu/people/">Zachary Lippman</a> at the <a href="https://www.cshl.edu/">Cold Spring Harbor Laboratory</a> in New York is using genome editing to manipulate traits that can help improve tomato yield. By tweaking genes native to two popular varieties of tomato plants, they have devised a rapid method to make the plants flower and produce ripe fruit more quickly. This means more plantings per growing season, which increases yield. It also means that the plant can be grown in latitudes more northerly than currently possible – an important attribute as the Earth’s climate warms.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/Jem3hP734uA?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Gene editing has produced tomatoes that flower and ripen weeks earlier.</span></figcaption>
</figure>
<p><strong>What’s next for you:</strong> Our research provides an atlas of candidates for future tomato gene function studies. We now can identify which genes were important at each stage of domestication history, and discover what they do. We also can search for beneficial alleles, or variants of specific genes, that may have been lost or diminished as the tomato was domesticated. We want to find out whether some of those lost variants could be used to improve growth and desirable traits in cultivated tomatoes.</p><img src="https://counter.theconversation.com/content/130041/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Hamid Razifard receives funding from National Science Foundation of USA. </span></em></p><p class="fine-print"><em><span>Ana Caicedo receives funding from the National Science Foundation (NSF) of the USA and the National Institute of Food and Agriculture (NIFA) of the USA. </span></em></p>Through genetic detective work, scientists have identified missing links in the tomato’s evolution from a wild blueberry-sized fruit in South America to the larger modern tomato of today.Hamid Razifard, Postdoctoral Researcher in Biology, UMass AmherstAna Caicedo, Associate Professor of Biology, UMass AmherstLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1281652019-12-05T16:02:32Z2019-12-05T16:02:32ZA 6,000-year-old fruit fly gave the world modern cheeses and yogurts<figure><img src="https://images.theconversation.com/files/305365/original/file-20191205-39023-1xjlqu8.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3458%2C2427&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">He died so that we might eat cheese.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/fruit-fly-380208508?src=2726c309-ebfc-414d-861f-cab0b366c33b-1-24">Vasekk/Shutterstock</a></span></figcaption></figure><p>Historians often trace the dawn of human civilisation back 10,000 years, when Neolithic tribes first settled and began farming in the Fertile Crescent, which stretches through much of what we now call the Middle East. Prehistoric peoples domesticated plants to create the cereal crops we still grow today, and in the Zagros mountains of Iran, Iraq and Turkey, <a href="https://science.sciencemag.org/content/287/5461/2254">sheep, goats and cows</a> were bred from their wild relatives to ensure a steady supply of meat and milk. But around the same time as plants and animals were tamed for agriculture, long before anyone even knew of microscopic life, early humans were domesticating microbes too.</p>
<p><a href="https://www.cell.com/current-biology/fulltext/S0960-9822(19)31384-3">In a paper published in Current Biology</a>, we discovered how “milk yeast” – the handy microorganism that can decompose lactose in milk to create dairy products like cheese and yoghurt – originated from a chance encounter between a fruit fly and a pail of milk around 5,500 years ago. This happy accident allowed prehistoric people to domesticate yeast in much the same way they domesticated crop plants and livestock animals, and produce the cheeses and yogurts billions of people enjoy today.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/305229/original/file-20191204-70126-jxdaj1.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/305229/original/file-20191204-70126-jxdaj1.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/305229/original/file-20191204-70126-jxdaj1.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/305229/original/file-20191204-70126-jxdaj1.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/305229/original/file-20191204-70126-jxdaj1.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/305229/original/file-20191204-70126-jxdaj1.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/305229/original/file-20191204-70126-jxdaj1.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">
<figcaption>
<span class="caption">Milk yeast cells are large and oval and here surrounded by rod-shaped bacterial cells.</span>
<span class="attribution"><span class="source">Loughlin Gethins & Suzanne Crotty, UCC</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>The domesticated diet</h2>
<p>Domestication is evolution directed by a human hand. After wild parents have bred, farmers retain the offspring with properties that are beneficial for future breeding. Take farmed wheat, for example. This crop species produces a lot more seeds than wild grasses do, because these seeds are the grain that humans harvest. Early farmers <a href="https://theconversation.com/what-3-000-year-old-egyptian-wheat-tells-us-about-the-genetics-of-our-daily-bread-126387">deliberately bred pairs of wheat plants</a> that produced lots of grain so that their offspring would inherit this trait. As these pairings were repeated over many generations, grain-rich descendants were gradually created. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/what-3-000-year-old-egyptian-wheat-tells-us-about-the-genetics-of-our-daily-bread-126387">What 3,000-year-old Egyptian wheat tells us about the genetics of our daily bread</a>
</strong>
</em>
</p>
<hr>
<p>It’s survival of the fittest, but the fittest are variants that have characteristics that are useful for humans. The wary and vicious wolf <a href="https://theconversation.com/why-dog-breeds-arent-considered-separate-species-56113">becomes the friendly and obedient dog</a>.</p>
<p>Neolithic farmers stumbled on the practice of domesticating microbes when they tried to preserve food by fermenting it. Fermentation relies on microbes, such as bacteria, yeast and fungi, increasing the acidity of the food to protect it against spoilage. Microbes that were good at making fermented products that were palatable and safe were kept to start the next batch, and so useful microbes were evolved and domesticated. “Baker’s yeast,” or <em>Saccharomyces cerevisiae</em>, was a microbe selected from nature to make beer, wine and other fermented drinks <a href="https://theconversation.com/thank-fungi-for-cheese-wine-and-beer-this-holiday-season-125793">13,000 years ago</a>.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/gourmet-meals-are-filled-with-bacteria-and-they-taste-delicious-57008">Gourmet meals are filled with bacteria – and they taste delicious</a>
</strong>
</em>
</p>
<hr>
<p><em>Kluyveromyces lactis</em>, or milk yeast, is found in French and Italian cheeses made from unpasteurised milk, and in natural fermented dairy drinks like <a href="https://www.bbcgoodfood.com/howto/guide/health-benefits-kefir">kefir</a>. But the ancestor of this microbe was originally associated with the fruit fly, so how did it end up making many of the dairy products that people eat today? We believe milk yeast owes its very existence to a fly landing in fermenting milk and starting an unusual sexual liaison. The fly in question was the common fruit fly, <em>Drosophila</em>, and it carried with it the ancestor of <em>K. lactis</em>. Although the fly died, the yeast lived, but with a problem – it could not use the lactose in milk as a food source. Instead, it found an unconventional solution – sex with its cousin.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/305359/original/file-20191205-39028-rntflh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/305359/original/file-20191205-39028-rntflh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/305359/original/file-20191205-39028-rntflh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/305359/original/file-20191205-39028-rntflh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/305359/original/file-20191205-39028-rntflh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/305359/original/file-20191205-39028-rntflh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/305359/original/file-20191205-39028-rntflh.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">Humans began fermenting milk to create cheeses and yogurts around 6,000 years ago.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/assorted-dairy-product-1161597100?src=f146c918-59b0-4df3-a58e-2cf3193d20d8-1-5">Margouillat photo/Shutterstock</a></span>
</figcaption>
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<p>When <em>K. lactis</em> arrived with the fly, its cousin <em>K. marxianus</em> was already happily growing in the milk. <em>K. marxianus</em> is able to use lactose for growth because it has two extra proteins which can help break down lactose into simple sugars that it then uses for energy. The cousins reproduced and the genes needed to use lactose transferred from <em>K. marxianus</em> to <em>K. lactis</em>. The end result was that <em>K. lactis</em> acquired two new genes and could then grow on lactose and survive on its own. The fermented product that <em>K. lactis</em> made must have been particularly delicious as it was used to start a new fermentation – a routine that has continued to the present day.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/do-humans-need-dairy-heres-the-science-70434">Do humans need dairy? Here's the science</a>
</strong>
</em>
</p>
<hr>
<p>We think that by 6,000 years ago, farmers were using fermented goat and sheep milk to make tasty beverages like yoghurt and kefir. We know that milk-producing animals – cows, sheep, goats – were all domesticated between 8,000 and 10,000 years ago, and <a href="https://www.bbc.com/news/science-environment-49650806">analysis of human tartar</a> found on teeth shows that humans were consuming milk, most likely as cheese or other fermented products by 5,500 years ago. The chance encounter between two yeast species and a little bit of illicit sex made all of this possible. </p>
<p>Who could’ve imagined that such a random series of events would produce so many of the world’s great culinary delicacies?</p><img src="https://counter.theconversation.com/content/128165/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>John Morrissey receives funding from the European Union Horizon 2020 Programme and from Science Foundation Ireland.</span></em></p>Your taste for cheese and yoghurt may never have been satisfied were it not for illicit microbial sex.John Morrissey, Lecturer in Microbiology, University College CorkLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1148002019-04-09T11:07:09Z2019-04-09T11:07:09ZMysterious museum shows how humans have modified nature for themselves – with important consequences<figure><img src="https://images.theconversation.com/files/268340/original/file-20190409-2898-njp1m4.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C1003%2C782&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Genetically modified mice express a green fluorescent protein which causes them to glow in the dark.</span> <span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:GFP_Mice_01.jpg">Moen et al. (2012)/Wikipedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>Humans have shaped aspects of the living world to suit themselves throughout their history. We’ve domesticated plants and animals for food, security and companionship for tens of <a href="https://www.britannica.com/science/domestication">thousand of years</a>, ensuring <a href="https://www.nature.com/articles/nature01019">early civilisations could survive</a>, develop, and eventually <a href="https://www.nationalgeographic.org/encyclopedia/domestication/">trade</a> with each other.</p>
<p>Throughout history, our relationship with other species has been tied to meeting human needs. Species have been <a href="https://www.yourgenome.org/facts/what-is-selective-breeding">selectively bred</a> so that their offspring over-express particular genetic traits, such as obedient behaviour in dogs or larger size and power in horses. </p>
<p>Over time humans have become more ambitious about <a href="http://science.sciencemag.org/content/316/5833/1866">choosing behavioural and physical traits</a> to embed in other life forms. In recent decades, humans have also become increasingly capable of <a href="https://www.yourgenome.org/facts/what-is-genetic-engineering">genetically engineering</a> species – manipulating their DNA by splicing or inserting genetic material from other species into their genome.</p>
<p>A museum which opened in Pittsburgh, USA in 2012 has sought to chart the human influence in the biology of other species. The <a href="https://postnatural.org/">Center for PostNatural History</a> invites visitors to explore how humans have shaped the living world, <a href="https://postnatural.org/About">defining “postnatural history”</a> as: </p>
<blockquote>
<p>the study of the origins, habitats, and evolution of organisms that have been intentionally and heritably altered by humans.</p>
</blockquote>
<p>The Center’s director and founder, <a href="https://www.cmu.edu/cas/people/pell_richard.html">Richard Pell</a>, went further in <a href="https://theinfluencers.org/en/center-for-postnatural-history/video/1">explaining the postnatural</a>.</p>
<blockquote>
<p>It’s not just giving a dog a weird haircut, it’s breeding a dog that has weird hair. And its offspring will have weird hair forever. It’s sculpting the evolutionary process. […] It’s that moment at which culture intervenes in nature, and the organism has not just a story to tell about evolution or habitat, but has a story to tell about us.</p>
</blockquote>
<h2>The postnatural planet</h2>
<p>The Center claims to be the world’s only museum that is exclusively focused on postnatural lifeforms, exhibiting species often <a href="https://vimeo.com/56855772">omitted from typical natural history museums</a>. There’s a <a href="https://theinfluencers.org/en/center-for-postnatural-history/video/2">hairless, obese rat</a>, fish which <a href="https://postnatural.org/Press-1/Nature-Interview">glow in the dark</a>, and <a href="https://postnatural.org/Exhibits/Transgenic-Mosquito-of-Southern-California">transgenic mosquitoes</a> which have been bred so they can’t carry dengue fever. There’s also a mix of familiar species – different breeds of dogs and chickens – and species often less associated with human interference, such as <a href="http://science.sciencemag.org/content/143/3606/538">corn</a>, <a href="https://www.sciencedirect.com/science/article/pii/S2405985416300295">bananas</a> and <a href="https://books.google.co.uk/books?hl=en&lr=&id=G95hgSRYy9kC&oi=fnd&pg=PA1&dq=domestication+%2522chestnut+tree%2522&ots=pcIuLzmX3n&sig=midn-DHfvCaYdWdzVfHGQCE2tNA#v=onepage&q=domestication%2520%2522chestnut%2520tree%2522&f=false">chestnut trees</a>. </p>
<p>All these species, and many others, have different genetic traits over-expressed to accentuate desirable features. Dogs, for example, have been domesticated and selectively bred out from a common wolf ancestor to more than <a href="http://www.fci.be/en/Nomenclature/">350 breeds</a>, according to strict guidelines in keeping with particular cultural desires around behavioural traits and visual qualities.</p>
<p>Often these human whims to breed dogs with flattened faces, aggressive behaviour or short legs have had <a href="https://books.google.co.uk/books?hl=en&lr=&id=ZOoRn4KgIawC&oi=fnd&pg=PR15&dq=dog+breeds+cause+health+disease+problems&ots=DvEXITZ9XH&sig=ijj7VYNsAAMFPLSY7JfN-hzyER4#v=onepage&q=dog%2520breeds%2520cause%2520health%2520disease%2520problems&f=false">little or no regard</a> for the species’ <a href="https://www.sciencedirect.com/science/article/pii/S1558787809001348">long-term welfare</a>.</p>
<p>These standards reflect the values and desires of those who bred them and are particularly evident in three exhibits at the museum. The Silkie chicken originated in China and has fluffy plumage - bred to satisfy visual desires rather than Western appetites for <a href="https://www.aspca.org/sites/default/files/chix_white_paper_nov2015_lores.pdf">enormous breasted</a> factory-farmed chickens, which are bred for <a href="https://theinfluencers.org/en/center-for-postnatural-history/video/1">uniform size</a> to fit in processing machines. </p>
<p>The Center also has a stuffed mount of an “alcoholic” rat, bred to choose alcohol over water when given the choice, as part of a laboratory experiment by researchers in Finland to <a href="https://www.nature.com/articles/ncb437">help find a cure for alcoholism</a>. Then there’s “Freckles” – a stuffed goat bred by the company Nexia to produce spider silk in her milk as a potential <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/j.1748-5967.2007.00121.x">replacement for Kevlar in military uniforms</a>.</p>
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<p>These three exhibits demonstrate how non-humans have been moulded to reflect human <a href="https://www.jstor.org/stable/622652?seq=1#metadata_info_tab_contents">expectations and desires</a>. The cultural systems which govern human life also increasingly apply to non-humans. It’s also no coincidence that the species discussed here have been bred in pursuit of profit, directly or indirectly. This suggests the pervasive influence of <a href="https://link.springer.com/article/10.1023/A:1006419715108">consumer capitalism</a> in human behaviour.</p>
<p>The most profitable organisms – such as cattle – have received the most investment and attention. The Belgian Blue cow, for example, has been bred for enormous, succulent and tasty shoulder and thigh muscles. But these mean <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/j.1439-0531.2006.00825.x">Caesarean sections</a> are needed to avoid <a href="https://www.rspca.org.uk/adviceandwelfare/farm/beef/keyissues">birth canal blockages</a>. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/267639/original/file-20190404-123405-tngn42.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/267639/original/file-20190404-123405-tngn42.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=402&fit=crop&dpr=1 600w, https://images.theconversation.com/files/267639/original/file-20190404-123405-tngn42.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=402&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/267639/original/file-20190404-123405-tngn42.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=402&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/267639/original/file-20190404-123405-tngn42.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=505&fit=crop&dpr=1 754w, https://images.theconversation.com/files/267639/original/file-20190404-123405-tngn42.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=505&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/267639/original/file-20190404-123405-tngn42.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=505&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The Belgian Blue’s muscular build reflects consumer demand for succulent thigh and shoulder meat but causes severe health problems for the animal.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Spitzenbulle.JPG">Mastiff/Wikipedia</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Profitable crop species are usually <a href="https://www.theguardian.com/environment/2017/oct/18/warning-of-ecological-armageddon-after-dramatic-plunge-in-insect-numbers">treated with pesticides to kill insects</a>, or <a>habitats are destroyed</a> to farm profitable species on. We leave little room for the species we haven’t exploited – <a href="https://www.ecowatch.com/biomass-humans-animals-2571413930.html">humans and livestock account for 96% of mammal biomass</a>.</p>
<p>This has created <a href="https://www.theguardian.com/environment/2014/sep/29/earth-lost-50-wildlife-in-40-years-wwf">dangerous imbalances in ecosystems</a>, while many of the species we exploit are being <a href="https://www.theguardian.com/news/2018/mar/12/what-is-biodiversity-and-why-does-it-matter-to-us">consumed faster than they can reproduce</a>. Humans have <a href="https://www.ufaw.org.uk/dogs/english-bulldog-dystocia">inserted themselves into the life cycles</a> of much of the living world, and these changes are heritable – their genetic trajectory is irreversibly set.</p>
<p>The Center for PostNatural History therefore shows us our collective power to shape the living world in our image. This power must be used responsibly.</p><img src="https://counter.theconversation.com/content/114800/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Dominic Walker 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>Human changes to the living world have benefited us, but the ecological consequences are mounting.Dominic Walker, Researcher in Cultural Geography, Royal Holloway University of LondonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1085592018-12-12T11:29:14Z2018-12-12T11:29:14ZHow chickens became the ultimate symbol of the Anthropocene<figure><img src="https://images.theconversation.com/files/249960/original/file-20181211-76974-7zsxft.jpg?ixlib=rb-1.1.0&rect=529%2C323%2C5461%2C3664&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Svetlana.Is / shutterstock</span></span></figcaption></figure><p>We are living on the planet of the chickens. The broiler (meat) chicken now outweighs all wild birds put together by three to one. It is the most numerous vertebrate (not just bird) species on land, with 23 billion alive at any one time. Across the world, chicken is the most commonly eaten meat. This has made it a vivid symbol of the <a href="https://theconversation.com/dawn-of-the-anthropocene-five-ways-we-know-humans-have-triggered-a-new-geological-epoch-52867">Anthropocene</a> – the proposed new geological epoch that marks the overwhelming impact of humans on the Earth’s surface geological processes. The modern bird is now so changed from its ancestors, that its distinctive bones will undoubtedly become fossilised markers of the time when humans reigned the planet. </p>
<p>In a recent study together with colleagues, published by <a href="http://rsos.royalsocietypublishing.org/lookup/doi/10.1098/rsos.180325">Royal Society Open Science</a>, we compared the bones of the modern meat chicken to the bones of their ancestors dating back to Roman times. Modern broiler chickens are radically different – they have a super-sized skeleton, distinct bone chemistry reflecting the homogeneity of their diet and significantly reduced genetic diversity. This is because a modern broiler is twice the size of a chicken from the medieval period and they have been bred for one thing: rapid weight gain. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/250010/original/file-20181211-76956-gjy7yh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/250010/original/file-20181211-76956-gjy7yh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/250010/original/file-20181211-76956-gjy7yh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=1258&fit=crop&dpr=1 600w, https://images.theconversation.com/files/250010/original/file-20181211-76956-gjy7yh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=1258&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/250010/original/file-20181211-76956-gjy7yh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=1258&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/250010/original/file-20181211-76956-gjy7yh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1581&fit=crop&dpr=1 754w, https://images.theconversation.com/files/250010/original/file-20181211-76956-gjy7yh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1581&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/250010/original/file-20181211-76956-gjy7yh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1581&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 modern broiler at five weeks old, alongside its ancestor the red jungle fowl at six weeks old (same scale).</span>
<span class="attribution"><a class="source" href="http://rsos.royalsocietypublishing.org/lookup/doi/10.1098/rsos.180325">Bennett et al / Royal Society</a>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The speed of growth accelerated in the second half of the 20th century, with the modern broiler putting on weight <a href="https://www.ncbi.nlm.nih.gov/pubmed/14601725">five times faster</a> than meat chickens from the 1950s. The result is that at just five or six weeks old they are already slaughter ready. The evidence of this extraordinary growth is preserved in their bones, which are less dense and often deformed. Poignantly, these birds cannot even be “rescued” from their factory farms – the strain of their enormous body means that if left to live even for another month, <a href="https://academic.oup.com/jas/article-abstract/90/6/2003/4764698">many birds die</a> from heart or respiratory failure. </p>
<p>The modern chicken only exists in its current form due to human intervention. We have altered their genes to mutate the receptor which <a href="https://www.nature.com/articles/nature08832">regulates their metabolism</a>, which means that the birds are always hungry and so will eat and grow more rapidly. Not only that, their entire life cycle is controlled by human technology. For example, the chickens are hatched in factories with computer-controlled temperature and humidity. From one day old, they live under electric lights to maximise the hours they can feed. Their slaughter by machine allows for thousands of birds to be processed every hour.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/249977/original/file-20181211-76971-1ib0tj9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/249977/original/file-20181211-76971-1ib0tj9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/249977/original/file-20181211-76971-1ib0tj9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/249977/original/file-20181211-76971-1ib0tj9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/249977/original/file-20181211-76971-1ib0tj9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/249977/original/file-20181211-76971-1ib0tj9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/249977/original/file-20181211-76971-1ib0tj9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/249977/original/file-20181211-76971-1ib0tj9.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">Controlled by humans – and their computers.</span>
<span class="attribution"><span class="source">David Tadevosian / shutterstock</span></span>
</figcaption>
</figure>
<p>Domesticated cows, pigs and sheep each number a billion or so, but it is chickens that are the most striking example of the modern biosphere. Their bones are scattered across landfill sites and farms worldwide and therefore have a good chance of being preserved in the rock record as symbols of how our planet and its biosphere has changed from its pre-human state to one dominated by humans and our <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1728-4457.2011.00450.x">domesticated animals</a>. </p>
<p>While humans have been selectively breeding chickens since their domestication in south-east Asia <a href="https://www.sciencedirect.com/science/article/pii/S027737911630107X">around 6,000 years ago</a>, the speed and scale of change in the 20th century is far beyond anything observed in the past. From the 1950s, the chicken population has risen in step with the rise in human population, as has our use of fossil fuels, plastics and other resources: now, this enfeebled and short-lived animal is more numerous than any bird species in Earth history.</p>
<p>What does the future hold? Right now, chicken consumption is on the rise. The meat is cheap, and many are moving away from beef and pork in order to reduce their greenhouse gas emissions. Somehow we must adapt to a growing population in a world affected by climate change. But business as usual may be off the cards. In a surprising move, the world’s largest chicken producers – Tyson Foods and Perdue Farms – are now investing in <a href="https://www.bloomberg.com/news/articles/2018-09-05/perdue-explores-non-meat-options-as-plant-protein-appetite-grows">plant-based proteins</a>. Does this mean the era of chickens could be over in a (geological) instant? </p>
<p>Nevertheless, the record of this human-engineered bird will be forever set in stone. Any intelligent species which arises in the far future – hyper-evolved rats or octopuses, perhaps? – will have a puzzle on their hands (or tentacles) in trying to figure out how and why millions of these rapidly-evolved bones lie mixed with the technofossil debris of the huge petrified dumpsites we will leave behind. As these future explorers reconstruct this bird – a creature far more helpless than the dodo – they may well rumble it too as a technological construct.</p><img src="https://counter.theconversation.com/content/108559/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span><a href="mailto:rmt12@le.ac.uk">rmt12@le.ac.uk</a> received funding from the Arts and Humanities Research Council and the City of London Archaeological Trust</span></em></p><p class="fine-print"><em><span>Carys Bennett, Jan Zalasiewicz, and Mark Williams 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>Our research shows that, millions of years from now, fossilised chicken bones will mark the era of human domination.Carys Bennett, Honorary Fellow in Geology, University of LeicesterJan Zalasiewicz, Senior Lecturer in Palaeobiology, University of LeicesterMark Williams, Professor of Palaeobiology, University of LeicesterRichard Thomas, Reader in Archaeology, University of LeicesterLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/922042018-02-22T19:08:17Z2018-02-22T19:08:17ZWhy it’s so hard to unravel the mysterious origins of domestic horses<figure><img src="https://images.theconversation.com/files/207517/original/file-20180222-152382-ln12dx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/infomastern/28016823760/sizes/l">Infomastern/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>There’s still a lot we don’t know about how, and where, horses were first domesticated. Experts long thought that all modern horses <a href="http://science.sciencemag.org/content/356/6336/442.full">were probably descended from</a> a group of animals that belonged to the Botai culture, which flourished in Kazakhstan around 5,500 years ago. </p>
<p>But now, <a href="http://science.sciencemag.org/content/early/2018/02/21/science.aao3297">a new study</a> published in Science suggests that the Botai horses were not the ancestors of our modern equine companions – and challenges what we thought we knew about one of the only “wild” horse species left today: the Przewalski’s horse. </p>
<p>There are now very few, if any, genuinely wild species of horse, which have never been domesticated. Scientists have known that Przewalski’s horse <a href="http://www.pnas.org/content/pnas/99/16/10905.full.pdf">is not an ancestor</a> of modern domestic horses, since studies were carried out on equine mitochondrial DNA in 2002. But now it seems that far from being the last remnants of a truly wild horse species, the Przewalski’s horse is the feral descendant of the domesticated Botai horses.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/207503/original/file-20180222-152360-1buta8u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/207503/original/file-20180222-152360-1buta8u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/207503/original/file-20180222-152360-1buta8u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=487&fit=crop&dpr=1 600w, https://images.theconversation.com/files/207503/original/file-20180222-152360-1buta8u.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=487&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/207503/original/file-20180222-152360-1buta8u.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=487&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/207503/original/file-20180222-152360-1buta8u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=612&fit=crop&dpr=1 754w, https://images.theconversation.com/files/207503/original/file-20180222-152360-1buta8u.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=612&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/207503/original/file-20180222-152360-1buta8u.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=612&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Study authors imagine what Przewalski’s ancient ancestors would have looked like.</span>
<span class="attribution"><span class="source">Ludovic Orlando, Seas Goddard, Alan Outram.</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Let’s take a look at the science. </p>
<h2>Born wild?</h2>
<p>Led by <a href="http://snm.ku.dk/english/staffsnm/staff/?pure=en%2Fpersons%2Fcharleen-gaunitz(17bfee3a-7ea7-4d8e-8d59-7b4a9c9cd40e)%2Fpublications.html">Charleen Gaunitz</a> from the Natural History Museum of Denmark, the study’s 47 authors sequenced the genomes of 42 ancient horses from Kazakhstan and various sites in Eurasia, and compared them with published data from 46 ancient and modern horses. </p>
<p>Their analysis showed that Przewalski’s horse and the most ancient horses from Eurasia were not genetically similar, as might be expected. In fact, the Przewalski’s horse were found to be most closely related to the Botai horses, while all modern domesticated horses belong to a separate group. If this is right, it turns what we thought we knew about wild and domestic horses on its head. </p>
<p>But one of the difficulties of drawing conclusions from the DNA of a modern Przewalski’s horse, is that the species suffered a massive decline in the first half of the 20th century. The last one seen in the wild was spotted <a href="http://www.appliedanimalbehaviour.com/article/S0168-1591(06)00334-0/fulltext">back in the 1960s</a>, and it was declared extinct in the wild. A captive breeding programme began, and all of <a href="http://www.jstor.org/stable/2386637?seq=1#page_scan_tab_contents">today’s Przewalski’s horses</a> trace their ancestry back to 13 individuals, which were in zoos around the world at the time. <em>Equus ferus przewalskii</em> was reintroduced to the wild at the end of the 20th century. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/207519/original/file-20180222-152354-1bzqx4l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/207519/original/file-20180222-152354-1bzqx4l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/207519/original/file-20180222-152354-1bzqx4l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/207519/original/file-20180222-152354-1bzqx4l.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/207519/original/file-20180222-152354-1bzqx4l.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/207519/original/file-20180222-152354-1bzqx4l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/207519/original/file-20180222-152354-1bzqx4l.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/207519/original/file-20180222-152354-1bzqx4l.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">Back where they belong: Przewalski’s horses in the Mongolian wilderness.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/garrettziegler/8582785530/sizes/l">gsz/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<p>Gaunitz and her colleagues suggest that there has been considerable invasion of modern horse genes into the species. But the team were fortunate enough to have DNA from one specimen dating to the 19th century, before the population collapse occurred. This allowed them to show that the Botai horses were direct ancestors of another breed of horse from the early bronze age, called Borly4, and that these Borly4 horses were the direct ancestors of the pre-collapse Przewalski’s horse.</p>
<h2>Unsolved mysteries</h2>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/207537/original/file-20180222-152382-9a5lt6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/207537/original/file-20180222-152382-9a5lt6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/207537/original/file-20180222-152382-9a5lt6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=904&fit=crop&dpr=1 600w, https://images.theconversation.com/files/207537/original/file-20180222-152382-9a5lt6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=904&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/207537/original/file-20180222-152382-9a5lt6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=904&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/207537/original/file-20180222-152382-9a5lt6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1135&fit=crop&dpr=1 754w, https://images.theconversation.com/files/207537/original/file-20180222-152382-9a5lt6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1135&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/207537/original/file-20180222-152382-9a5lt6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1135&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Who nose?</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/rachelpatterson/4734833430/sizes/l">RPatts/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<p>This leaves the origins of modern horses shrouded in mystery. It seems they are descended from a completely different group of horses, but the genomic analysis suggests that they managed to interbreed with the Botai horses to a small degree as the population expanded across the continental landmass. The authors of the study suggest that Hungary, in Eastern Europe, might be one of a number of places where the ancestors of modern horses were first domesticated, because the oldest horse remains were recovered from there. </p>
<p>Earlier studies have suggested Iberia, North Africa and Eurasia <a href="http://repositorio.ul.pt/bitstream/10451/28846/1/Silvaetal-2015-DNA-Horse.pdf">as possible sites of domestication</a>. And it seems likely that horses – like dogs – were independently domesticated in a number of different places and over a long period of time. </p>
<p>Scientists – and horse owners – often wonder exactly how horses were domesticated. It has been suggested that they were <a href="https://link.springer.com/article/10.1007/s10963-011-9051-9">originally prey animals</a> that humans began to protect and breed to ensure a steady supply of meat. Over time their keepers began to use them for milk, hides and transport. Alternatively, they may have been <a href="https://s3.amazonaws.com/academia.edu.documents/31931403/Zeder.Geptsetal.2012.pdf?AWSAccessKeyId=AKIAIWOWYYGZ2Y53UL3A&Expires=1519131580&Signature=XqV92fZnYo39Pl%2BP1ot6%2BvfGfRQ%3D&response-content-disposition=inline%3B%20filename%3DPathways_to_Animal_Domestication.pdf">deliberately brought under human control</a> to help with the hunting of wild horse herds. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/207521/original/file-20180222-152357-woqryq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/207521/original/file-20180222-152357-woqryq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/207521/original/file-20180222-152357-woqryq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/207521/original/file-20180222-152357-woqryq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/207521/original/file-20180222-152357-woqryq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/207521/original/file-20180222-152357-woqryq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/207521/original/file-20180222-152357-woqryq.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">
<figcaption>
<span class="caption">Catch us if you can.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/brian395/35008830402/sizes/l">Brian395/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Whatever the method, it now seems likely that the very robust horses of the Botai were not the ultimate ancestors of the delicate modern thoroughbred racehorse, nor of the heavy draft horses that were the staple workforce of agriculture in many parts of the world until the beginning of the 20th century. </p>
<p>The Botai horse genes are preserved only in the small and precarious populations of Przewalski’s horse, which struggle to survive in <a href="http://www.appliedanimalbehaviour.com/article/S0168-1591(06)00334-0/fulltext">the areas of the Gobi desert</a> and the mountain steppe regions of Mongolia where they were reintroduced. All the more reason then, to continue to ensure the survival of this species – possibly the last repository of ancient horse DNA.</p><img src="https://counter.theconversation.com/content/92204/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jan Hoole 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>A new study of ancient Botai horses turns our knowledge about wild and domestic horses on its head.Jan Hoole, Lecturer in Biology, Keele UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/795842017-06-19T15:10:42Z2017-06-19T15:10:42ZAncient DNA reveals how cats conquered the world<figure><img src="https://images.theconversation.com/files/174477/original/file-20170619-27202-dxytnv.jpg?ixlib=rb-1.1.0&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>Humans may have had pet cats for as long as 9,500 years. In 2004, archaeologists in Cyprus found <a href="science.sciencemag.org/content/304/5668/259">a complete cat skeleton</a> buried in a Stone Age village. Given that Cyprus has no native wildcats, the animal (or perhaps its ancestors) must have been brought to the island by humans all those millennia ago.</p>
<p>Yet despite our long history of keeping pet cats and their <a href="https://www.researchgate.net/profile/Jane_Murray5/publication/281644650_Assessing_changes_in_the_UK_pet_cat_and_dog_populations_numbers_and_household_ownership/links/5656e5d908ae4988a7b50eb0.pdf">popularity today</a>, felines aren’t the easiest of animals to domesticate (as anyone who’s felt a cat’s cold shoulder might agree). There is also little evidence in the archaeological record to show how cats became our friends and went on to spread around the world.</p>
<p>Now a new DNA study published in <a href="http://nature.com/articles/doi:10.1038/s41559-017-0139">Ecology and Evolution</a> suggests how cats may have followed the development of Western civilisation along land and sea trade routes. This process was eventually helped by a more concerted breeding attempt in the 18th century, creating the much-loved domestic short-haired or “tabby” cat we know today.</p>
<p>While the origin of the domesticated cat is still a mystery, it seems likely the process of becoming pets took a very long time. It seems that, because cats are so <a href="https://books.google.co.uk/books?hl=en&lr=&id=m-NRAgAAQBAJ&oi=fnd&pg=PA63&dq=social+behaviour+of+cats&ots=DOHsPwVzo5&sig=aI8zsdc0XKd1Ara2S0LoiGQXE2I#v=onepage&q=social%20behaviour%20of%20cats&f=false">independent, territorial</a> and, at times, downright antisocial, they were not so easy to domesticate as the co-operative, pack-orientated wolf. <a href="http://www.pnas.org/content/106/Supplement_1/9971.full">It’s likely</a> that cats lived around humans for many centuries before succumbing to the lure of the fire and the cushion, and coming in from the cold to become true companions to humans.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/174453/original/file-20170619-12445-1abnqrz.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/174453/original/file-20170619-12445-1abnqrz.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=464&fit=crop&dpr=1 600w, https://images.theconversation.com/files/174453/original/file-20170619-12445-1abnqrz.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=464&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/174453/original/file-20170619-12445-1abnqrz.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=464&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/174453/original/file-20170619-12445-1abnqrz.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=583&fit=crop&dpr=1 754w, https://images.theconversation.com/files/174453/original/file-20170619-12445-1abnqrz.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=583&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/174453/original/file-20170619-12445-1abnqrz.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">
<figcaption>
<span class="caption">The ancestors of today’s domestic cats encountered and interbred with various wildcat species.</span>
<span class="attribution"><span class="source">Ottoni et al., 2017/Nature</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The cat found in Cyprus corresponds to the Neolithic period of around 10,000 BC to 4,000 BC and the <a href="onlinelibrary.wiley.com/doi/10.1525/aa.1991.93.1.02a00030/full">agricultural revolution</a>. This was when people were beginning to settle down and become farmers instead of carrying on the nomadic hunter-gatherer existence that humans had followed for the previous 200,000 years or so. An <a href="http://science.sciencemag.org/content/317/5837/519">earlier DNA study</a> of other ancient remains confirms that domestic cats first emerged in what archaeologists call the Near East, the land at the eastern end of the Mediterranean where some of the first human civilisations emerged.</p>
<p>Of course, farming brings its own problems, including infestations of rats and mice, so perhaps it’s not surprising that it is at this time that we see the first occurrence of a cat <a href="https://lirias.kuleuven.be/handle/123456789/522935">buried in a human grave</a>. It’s not hard to imagine that early farmers might have encouraged cats to stay around by helping them out with food during lean times of the year, and allowing them to come into their houses.</p>
<p>The gaps in the archaeological record mean that, after the Cyprus remains, evidence for domestic cats doesn’t appear again for thousands of years. More cat graves then <a href="http://www.sciencedirect.com/science/article/pii/S0305440314000636">start to appear</a> among ancient Egyptian finds (although there is <a href="https://www.theguardian.com/science/2013/dec/17/ancient-cat-bone-research-china-domestic-pet">also evidence</a> for tame cats in Stone Age China). It was in Egypt that cats really got their furry paws under the table and became not just part of the family but objects of religious worship.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/SgZKFVaSDRw?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<p>To track the spread of the domestic cat, the authors of the new study examined DNA taken from bones and teeth of ancient cat remains. They also studied samples from the skin and hair of mummified Egyptian cats (and you thought emptying the litter tray was bad enough).</p>
<p>They found that all modern cats have ancestors among the Near Eastern and Egyptian cats, although the contributions of these two groups to the gene pool of today’s cats probably happened at different times. From there, the DNA analysis suggests domestic cats spread out over a period of around 1,300 years to the 5th century AD, with remains recorded in Bulgaria, Turkey and Jordan.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/174434/original/file-20170619-12397-14naxg2.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/174434/original/file-20170619-12397-14naxg2.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/174434/original/file-20170619-12397-14naxg2.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=303&fit=crop&dpr=1 600w, https://images.theconversation.com/files/174434/original/file-20170619-12397-14naxg2.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=303&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/174434/original/file-20170619-12397-14naxg2.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=303&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/174434/original/file-20170619-12397-14naxg2.PNG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=381&fit=crop&dpr=1 754w, https://images.theconversation.com/files/174434/original/file-20170619-12397-14naxg2.PNG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=381&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/174434/original/file-20170619-12397-14naxg2.PNG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=381&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">‘Blotched’ tabby cat genes became more common alongside striped ‘mackerel’ patterns in the later Middle Ages.</span>
<span class="attribution"><span class="source">Ottoni et al., 2017/Nature, Ashmolean Museum, University of Oxford</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Over the next 800 years, domestic cats spread further into northern Europe. But it wasn’t until the 18th century that the traditional “mackerel” coat of the wildcat began to change in substantial numbers to the blotched pattern that we see in many modern tabbies. This suggests that, at that time, serious efforts to breed cats for appearance began – perhaps the origin of modern cat shows.</p>
<p>Another interesting finding is that domestic cats from earliest times, when moved around by humans to new parts of the world, promptly mated with local wildcats and spread their genes through the population. And, in the process, they permanently changed the gene pool of cats in the area.</p>
<p>This has particular relevance to today’s efforts to protect the endangered European wildcat, because conservationists often think <a href="https://link.springer.com/article/10.1007/s13364-015-0253-x">interbreeding with domestic cats</a> is one of the greatest threats to the species. If this has been happening all over the old world for the past 9,000 or so years, then perhaps it’s time to stop worrying about wildcats breeding with local moggies. This study suggests that none of the existing species of non-domesticated cats is likely to be pure. In fact, cats’ ability to interbreed has helped them conquer the world.</p><img src="https://counter.theconversation.com/content/79584/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jan Hoole 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>Scientists have shown the origins of today’s popular ‘tabby’ cat.Jan Hoole, Lecturer in Biology, Keele UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/774342017-05-16T11:05:43Z2017-05-16T11:05:43ZDid the first farmers deliberately domesticate wild plants?<figure><img src="https://images.theconversation.com/files/169331/original/file-20170515-7005-1upz4a.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Egyptian_harvest.jpg">Scanned from 'The Oxford encyclopedia of ancient Egypt'</a></span></figcaption></figure><p>The beginning of agriculture <a href="https://theconversation.com/andrea-leadsom-is-wrong-about-the-history-of-farming-and-heres-why-it-matters-70923">changed human history</a> and has fascinated scholars for centuries. Yet it’s hard to study because it happened 10,000 or so years ago. As a result, a number of important issues remain unresolved, including why hunter-gatherers first began farming, and how crops were domesticated to depend on people.</p>
<p>Domesticated crops have been transformed almost beyond recognition in comparison with their wild relatives. Look at how maize differs from its wild equivalents, for instance:</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/169337/original/file-20170515-6984-clo9tj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/169337/original/file-20170515-6984-clo9tj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/169337/original/file-20170515-6984-clo9tj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=376&fit=crop&dpr=1 600w, https://images.theconversation.com/files/169337/original/file-20170515-6984-clo9tj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=376&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/169337/original/file-20170515-6984-clo9tj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=376&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/169337/original/file-20170515-6984-clo9tj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=473&fit=crop&dpr=1 754w, https://images.theconversation.com/files/169337/original/file-20170515-6984-clo9tj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=473&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/169337/original/file-20170515-6984-clo9tj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=473&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Maize, or corn, is a domesticated version of teosinte, a grass found in Mexico.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/nsf_beta/3745571067">Nicolle Rager Fuller, National Science Foundation</a></span>
</figcaption>
</figure>
<p>This transformation largely happened during the early stages of farming, back in the Stone Age, when crops were first deliberately sown, tended and harvested using stone sickles. </p>
<p>One controversy in this area is about the extent to which ancient peoples knew they were domesticating crops. Did anyone in 8,000BC think thin, wispy “teosintes” could one day <a href="http://learn.genetics.utah.edu/content/selection/corn/">become corn on the cob</a>? Did anyone really look at <a href="http://www.sciencemag.org/news/2015/11/study-argues-rice-was-domesticated-least-three-times">wild rice</a> and imagine turning it into basmati or long-grain? Many archaeologists think not, but it’s difficult to rule out deliberate breeding.</p>
<p>The question is whether these first farmers knowingly bred domesticated crops, or whether domestication characteristics simply evolved as farmers repeatedly cultivated and harvested wild plants?</p>
<p>To investigate this, colleagues and I have a new paper published <a href="http://onlinelibrary.wiley.com/doi/10.1002/evl3.6/epdf">Evolution Letters</a> in which we looked at seed sizes in wild and domesticated plants. Domesticated cereal crops such as wheat, rice or maize have lost the ability to disperse their seeds naturally – they no longer fall off the plants by themselves, and instead depend on people or machines to plant them. Their seeds have become much larger, however. Maize seeds are 15 times bigger than wild teosinte, while soybeans are seven times larger than their wild relatives. Even in plants like barley, a more modest increase in seed size (60% larger) translates into <a href="http://onlinelibrary.wiley.com/wol1/doi/10.1111/1365-2435.12760/abstract">hugely increased yield</a>.</p>
<p>Of course, the farmers who bred the early versions of these crops may have been targeting large seeds because they knew these would give larger yields. This is why we also compared cereal crops with vegetables. This gets around the problem of looking at seed size in crops that were grown for their grain.</p>
<p>Any selective breeding of vegetables by early farmers would have acted on the leaves, stems or roots that were eaten as food, but should not have directly affected seed size. Instead, any changes in vegetable seed size probably arose unintentionally. </p>
<p>Natural selection could have caused larger seeds to evolve in cultivated fields if larger seedlings competed or survived better than smaller ones. Larger seeds could also have resulted from genetic links to other characteristics like overall plant size. In this case, people might have bred larger crops by saving and planting seeds from the biggest plants, or unintentionally by thinning out small plants while preserving larger ones. But larger seeds would not have been inevitable – there are many plants which are large when mature, but grow from small seeds.</p>
<p>We gathered together seed size data for lots of modern crops and living examples of their wild relatives. Across seven vegetable species we found strong evidence for a general enlargement of seeds due to domestication. This is especially stunning in crops like potato, cassava and sweet potato, where people don’t even plant seeds, let alone harvest them. It is hard to think of any reason why people would breed large seeds in these crops. Instead, larger seeds in these species (found in the flowering plant above ground) surely arose unintentionally. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/169341/original/file-20170515-6987-jsipst.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/169341/original/file-20170515-6987-jsipst.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/169341/original/file-20170515-6987-jsipst.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/169341/original/file-20170515-6987-jsipst.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/169341/original/file-20170515-6987-jsipst.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/169341/original/file-20170515-6987-jsipst.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/169341/original/file-20170515-6987-jsipst.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/169341/original/file-20170515-6987-jsipst.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A sweet potato root system. Potatoes are generally grown from existing potatoes or cuttings yet their seeds have still become larger since domestication.</span>
<span class="attribution"><span class="source">saint1533/Pixabay</span></span>
</figcaption>
</figure>
<p>If early farmers unintentionally produced vegetables with larger seeds simply by cultivating them, then what about grain crops? The size of the domestication effect for vegetable seeds falls completely within the range seen in cereals and pulse grains like lentils and beans. This makes it likely that at least part of the seed enlargement in these crops also evolved during domestication without deliberate foresight from Stone Age farmers – people did not set out to breed larger grains, but these evolved through natural selection or genetic links to plant size.</p>
<p>Our findings have important implications for understanding how crops evolved. Unintentional selection was probably more important in the genesis of our food plants than previously realised. Early increases in the yields of crops might well have evolved in farmers’ fields rather than being bred artificially.</p><img src="https://counter.theconversation.com/content/77434/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Colin Osborne receives funding from the UK Natural Environment Research Council (NERC) and the European Research Council (ERC). </span></em></p>New study finds little evidence that farmers consciously tried to turn wild plants into more useful crops.Colin Osborne, Professor of Plant Biology, University of SheffieldLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/682072017-03-10T04:19:06Z2017-03-10T04:19:06ZWhy losing a dog can be harder than losing a relative or friend<figure><img src="https://images.theconversation.com/files/160225/original/image-20170309-21047-yikfkr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Dogs are a big part of their owners' routines – which makes their loss even more jarring.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/download/confirm/83837074?size=huge_jpg">'Silhouette' via www.shutterstock.com</a></span></figcaption></figure><p>Recently, my wife and I went through one of the more excruciating experiences of our lives – the euthanasia of our beloved dog, Murphy. I remember making eye contact with Murphy moments before she took her last breath – she flashed me a look that was an endearing blend of confusion and the reassurance that everyone was ok because we were both by her side. </p>
<p>When people who have never had a dog see their dog-owning friends mourn the loss of a pet, they probably think it’s all a bit of an overreaction; after all, it’s “just a dog.” </p>
<p>However, those who have loved a dog know the truth: Your own pet is never “just a dog.” </p>
<p>Many times, I’ve had friends guiltily confide to me that they grieved more over the loss of a dog than over the loss of friends or relatives. <a href="http://www.ehbonline.org/article/S0162-3095(99)80001-4/abstract">Research has confirmed</a> that for most people, the loss of a dog is, in almost every way, comparable to the loss of a human loved one. Unfortunately, there’s little in our cultural playbook – no grief rituals, no obituary in the local newspaper, no religious service – to help us get through the loss of a pet, which can make us feel more than a bit <a href="http://www.telegraph.co.uk/lifestyle/9467927/Why-like-Ben-Fogle-are-we-embarrassed-to-show-grief-over-our-dead-pets.html">embarrassed to show too much public grief over our dead dogs</a>. </p>
<p>Perhaps if people realized just how strong and intense the bond is between people and their dogs, such grief would become more widely accepted. This would greatly help dog owners to integrate the death into their lives and help them move forward.</p>
<h2>An interspecies bond like no other</h2>
<p>What is it about dogs, exactly, that make humans bond so closely with them?</p>
<p>For starters, dogs have had to adapt to living with humans over the past 10,000 years. And they’ve done it very well: They’re the only animal to have evolved specifically to be our companions and friends. <a href="http://brianhare.net/">Anthropologist Brian Hare</a> has developed the “Domestication Hypothesis” to explain how dogs morphed from their grey wolf ancestors into the socially skilled animals that we now interact with in very much the same way as we interact with other people.</p>
<p>Perhaps one reason our relationships with dogs can be even more satisfying than our human relationships is that dogs provide us with such unconditional, uncritical positive feedback. (<a href="https://img1.etsystatic.com/155/0/13618223/il_340x270.1142491229_fvka.jpg">As the old saying goes</a>, “May I become the kind of person that my dog thinks I already am.”) </p>
<p>This is no accident. They have been selectively bred through generations to pay attention to people, and <a href="https://www.psychologytoday.com/blog/canine-corner/201608/do-your-dog-love-you-more-food">MRI scans show</a> that dog brains respond to praise from their owners just as strongly as they do to food (and for some dogs, praise is an even more effective incentive than food). Dogs recognize people and can learn to interpret human emotional states <a href="http://cdp.sagepub.com/content/25/5/339.full">from facial expression alone</a>. Scientific studies also indicate that dogs can understand human intentions, <a href="http://cdp.sagepub.com/content/25/5/322.full">try to help their owners</a> and <a href="https://www.psychologytoday.com/blog/canine-corner/201508/dogs-avoid-people-who-are-not-cooperative-their-owners">even avoid people</a> who don’t cooperate with their owners or treat them well.</p>
<p>Not surprisingly, humans respond positively to such unqualified affection, assistance and loyalty. Just looking at dogs <a href="https://www.psychologytoday.com/blog/canine-corner/201609/just-looking-dog-can-make-you-smile">can make people smile</a>. <a href="https://www.psychologytoday.com/blog/canine-corner/201607/stop-the-presses-dog-owners-are-happier">Dog owners score higher on measures of well-being</a> and they are happier, on average, than people who own cats or no pets at all.</p>
<h2>Like a member of the family</h2>
<p>Our strong attachment to dogs was subtly revealed in <a href="https://www.psychonomic.org/news/311582/Roll-calling-the-dog-but-not-the-cat.htm">a recent study</a> of “misnaming.” Misnaming happens when you call someone by the wrong name, like when parents mistakenly call one of their kids by a sibling’s name. It turns out that the name of the family dog also gets confused with human family members, indicating that the dog’s name is being pulled from the same cognitive pool that contains other members of the family. (Curiously, the same thing rarely happens with cat names.) </p>
<p>It’s no wonder dog owners miss them so much when they’re gone. </p>
<p><a href="http://psychcentral.com/lib/grieving-the-loss-of-a-pet/">Psychologist Julie Axelrod has pointed out</a> that the loss of a dog is so painful because owners aren’t just losing the pet. It could mean the loss of a source of unconditional love, a primary companion who provides security and comfort, and maybe even a protégé that’s been mentored like a child. </p>
<p>The loss of a dog can also seriously disrupt an owner’s daily routine more profoundly than the loss of most friends and relatives. For owners, their daily schedules – even their vacation plans – can revolve around the needs of their pets. Changes in lifestyle and routine are <a href="http://www.simplypsychology.org/SRRS.html">some of the primary sources of stress</a>. </p>
<p><a href="http://www.sciencedirect.com/science/article/pii/S1090513816301088">According to a survey</a>, many bereaved pet owners will even mistakenly interpret ambiguous sights and sounds as the movements, pants and whimpers of the deceased pet. This is most likely to happen shortly after the death of the pet, especially among owners who had very high levels of attachment to their pets. </p>
<p>While the death of a dog is horrible, dog owners have become so accustomed to the reassuring and nonjudgmental presence of their canine companions that, more often than not, they’ll eventually get a new one. </p>
<p>So yes, I miss my dog. But I’m sure that I’ll be putting myself through this ordeal again in the years to come.</p>
<p>[ <em>Like what you’ve read? Want more?</em> <a href="https://theconversation.com/us/newsletters?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=likethis">Sign up for our daily newsletter</a>. ]</p><img src="https://counter.theconversation.com/content/68207/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Frank T. McAndrew 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>Many are embarrassed to publicly show too much grief over the death of a dog. But research has shown just how devastating the loss can be.Frank T. McAndrew, Cornelia H. Dudley Professor of Psychology, Knox CollegeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/738782017-03-03T09:37:15Z2017-03-03T09:37:15ZThe Amazon’s ancient human history is written in its trees<figure><img src="https://images.theconversation.com/files/159171/original/image-20170302-14703-1v3kcvx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A Yanomami woman cultivates a medicinal tree.</span> <span class="attribution"><span class="source">William Milliken, RBG Kew</span></span></figcaption></figure><p>When I started doing fieldwork in Borneo 17 years ago, most people thought of tropical forests as wildernesses, hostile to civilised human life and home only to vagrant, primitive people. Major textbooks portrayed these forests as largely unchanging over several million years.</p>
<p>This mindset suited common political goals, previously for imperial expansion and more lately for corporate development. Logging, ranching, mining and dam construction were seen as bringing better lives to impoverished (and inferior) hunter-gatherers and small-scale farmers.</p>
<p>In fact, there is growing evidence that tropical forests have been cultivated on an impressive scale for thousands of years. But there is still intense debate about the extent to which ancient human actions have altered tropical forests.</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/159193/original/image-20170302-14682-17x89du.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/159193/original/image-20170302-14682-17x89du.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/159193/original/image-20170302-14682-17x89du.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/159193/original/image-20170302-14682-17x89du.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/159193/original/image-20170302-14682-17x89du.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/159193/original/image-20170302-14682-17x89du.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/159193/original/image-20170302-14682-17x89du.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">Domesticated trees.</span>
<span class="attribution"><span class="source">Carolina Levis</span></span>
</figcaption>
</figure>
<p><a href="http://science.sciencemag.org/cgi/doi/10.1126/science.aal0157">A new study</a> of the current plantlife of the Amazon rainforest shows it has been significantly shaped by ancient people, including sophisticated groups that died out more than 500 years ago. Not only could the information about these living plants teach us about these ancient cultures, it could also help improve our approach to managing the forest today. </p>
<p>The researchers, led by the <a href="https://science.naturalis.nl/en/">Naturalis Biodiversity Centre in the Netherlands</a>, looked at 1,091 mostly one-hectare plots of land across the Amazon. They identified 85 tree species that showed signs of at least some domestication before the first Western contact, of which 20 were very common species including the cocoa tree, the Amazon grape and the Brazil nut.</p>
<p>They then compared how these domesticated trees, particularly the 20 common ones, were distributed against the pattern of evidence for ancient human activity. This included <a href="http://science.sciencemag.org/content/321/5893/1214">archaeological sites</a> <a href="http://www.mdpi.com/1424-2818/2/4/473/htm">and soils</a> showing evidence for ancient cultivation. The two sets of data didn’t cover precisely the same places. But the researchers were still able to show that plots closer to evidence for ancient human activity regularly contained many more domesticated trees.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/159182/original/image-20170302-14724-bzarm3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/159182/original/image-20170302-14724-bzarm3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/159182/original/image-20170302-14724-bzarm3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/159182/original/image-20170302-14724-bzarm3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/159182/original/image-20170302-14724-bzarm3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/159182/original/image-20170302-14724-bzarm3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/159182/original/image-20170302-14724-bzarm3.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">
<figcaption>
<span class="caption">Mauritia flexuosa, a common domesticated Amazon trees.</span>
<span class="attribution"><span class="source">Hans ter Steege</span></span>
</figcaption>
</figure>
<p>This pattern suggests ancient people were probably managing these species within the forests by controlling the kinds of tree that grew – and quite possibly cultivating desirable trees. Some plots far from known archaeological sites also had high numbers of domesticated trees. This might be because they are close to undiscovered archaeological sites. Environmental variables and seasonality of rainfall also accounted for some of the patterning.</p>
<p>The link between domesticated trees and ancient human activity was particularly noticeable on the southwestern edge of the Amazon basin. This area is <a href="http://www.mdpi.com/1424-2818/2/1/72/htm">known to be the origin</a> of many of the domesticated trees and crops such as manioc. And it also has the oldest evidence for human activity, with ancient cultivated soils dating from around <a href="https://scholar.google.com/scholar_lookup?author=EG+Neves&author=JB+Petersen&author=RN+Bartone&author=CA+Silva&title=Historical+and+socio-cultural+origins+of+Amazonian+dark+earth&publication_year=2003&pages=29-50">4,800 years ago</a>. </p>
<h2>Human impact</h2>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/159186/original/image-20170302-14690-evbtxs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/159186/original/image-20170302-14690-evbtxs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=802&fit=crop&dpr=1 600w, https://images.theconversation.com/files/159186/original/image-20170302-14690-evbtxs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=802&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/159186/original/image-20170302-14690-evbtxs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=802&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/159186/original/image-20170302-14690-evbtxs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1008&fit=crop&dpr=1 754w, https://images.theconversation.com/files/159186/original/image-20170302-14690-evbtxs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1008&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/159186/original/image-20170302-14690-evbtxs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1008&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Peach palm was domesticated by pre-Colombian people.</span>
<span class="attribution"><span class="source">Tinde van Andel</span></span>
</figcaption>
</figure>
<p>We know from accounts of the <a href="http://www.worldcat.org/title/discovery-of-the-amazon-according-to-the-account-of-friar-gaspar-de-carvajal-and-other-documents/oclc/358733">first Western voyages of discovery</a> that tropical forests once had sophisticated societies that organised and used the vegetation on an impressive scale. And a growing body of recent research has suggested that wide-scale cultivation of a wide variety of plants in the Amazon <a href="http://www.sciencedirect.com/science/article/pii/S2213305414000241">goes back much further</a>. <a href="http://rspb.royalsocietypublishing.org/content/282/1812/20150813">One study from 2015</a> suggests people were domesticating plants there as long as 8,000 years ago. And in the past year, <a href="http://www.pnas.org/content/114/8/1868">evidence has emerged</a> of enormous agricultural settlements and cities lying abandoned below the tropical forest.</p>
<p>But what we haven’t known is the impact on the forest of this activity, which largely ended 500 years ago when the population collapsed as the result of epidemic diseases introduced from Europe. Doing research in the tropical forests of the world is extremely arduous, dangerous and expensive. As a result, many projects are small in scale and are therefore limited in what they can tell us. In many respects, the size, scope and rigour of this latest study provides much stronger proof of the depth of the human shaping of tropical forests than we have ever had before. </p>
<p>This matters, on many levels. It could help those trying to balance the desperate need to develop modern productive systems with the <a href="https://books.google.co.uk/books?hl=en&lr=&id=8XO-tpu8ae0C&oi=fnd&pg=PR10&dq=Conservation+and+indigenous+peoples&ots=Ajx79brfBb&sig=iYlBO2oH3mniKye0gfTX_zfJqto&redir_esc=y#v=onepage&q=Conservation%20and%20indigenous%20peoples&f=false">need to conserve forests and recognise the rights of their indigenous peoples</a>. It could also benefit conservationists striving to find the best ways to manage these increasingly <a href="http://www.nature.com/nature/journal/v404/n6780/full/404836a0.html">fragmented and damaged ecosystems</a>. Not least, recognising land use as a mark of ownership and therefore land rights is vital for the <a href="http://onlinelibrary.wiley.com/doi/10.1111/j.1470-9856.2000.tb00119.x/full">indigenous peoples</a> themselves.</p>
<p>Today, parts of the tropical forests of this vast region are still cultural artefacts, reflecting the activities of generations of sophisticated cultivators and forest managers. It is time for us all to see the tropical forests of the world in a new light, and <a href="https://books.google.co.uk/books?hl=en&lr=&id=dw5VwTKm1PoC&oi=fnd&pg=PR10&dq=Conservation+and+indigenous+peoples&ots=zQ47StheWZ&sig=UI8pIzPFufsh8SytrLnECZp30fs&redir_esc=y#v=onepage&q=Conservation%20and%20indigenous%20peoples&f=false">to recognise the important role of their indigenous populations in shaping them</a> –- and in their future management.</p><img src="https://counter.theconversation.com/content/73878/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Chris O Hunt has received funding from the British Academy, AHRC and the Evans Fund for work in tropical forests. </span></em></p>New research shows how ancient rainforest cultures have left their mark on today’s plantlife.Chris Hunt, Professor of Cultural Palaeoecology, Liverpool John Moores UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/650182016-09-14T11:37:25Z2016-09-14T11:37:25ZWhy zebra refused to be saddled with domesticity<figure><img src="https://images.theconversation.com/files/137405/original/image-20160912-19237-dlsfl4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Just a stripey horse? Neigh ...</span> <span class="attribution"><a class="source" href="http://www.shutterstock.com/pic-281622710/stock-photo-zebra.html?src=tWar6vP5ZHAoJNCfWRt9gA-1-0">Shutterstock</a></span></figcaption></figure><p>In many ways, zebra appear very like horses (or ponies, given their size). Yet underlying differences in behaviour have meant that while horses and donkeys have been successfully domesticated, the zebra remains predominantly wild. So how did the zebra avoid the load bearing, farm working, fence jumping fate of its cousins? And which animal ended up with the better deal?</p>
<p>Because of their obvious similarity to horses – and for novelty value – attempts have been made by humans to ride and race zebra. The 2005 movie, <a href="http://www.film4.com/reviews/2005/racing-stripes">Racing Stripes</a>, was the story of a young zebra who wanted to compete in horse races – although the filmmakers were forced to use a horse stand-in for some scenes (the tail gives it away). </p>
<p>The manes and tails of zebra are in fact more similar to those of asses (donkeys) and reflect the <a href="http://chem.tufts.edu/science/evolution/HorseEvolution.htm">evolutionary history of the genus Equus</a>. Although horses, assess and zebra all evolved from a common ancestor (<a href="https://www.britannica.com/animal/dawn-horse">Hyracotherium</a>) which lived in Europe and North America around 55m years ago, divergence meant that the zebra and donkey are more closely related to each other than either is to the horse.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/PL64Q_JM5qw?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<p>The North American equids (members of the horse family) <a href="http://www.horsetalk.co.nz/2012/11/29/why-did-horses-die-out-in-north-america/#axzz4KE50zAfX">disappeared</a> about 8-10,000 years ago, and in Europe and Asia, Palaeolithic man extensively hunted the herds of wild horses on the open plains. A combination of climatic change, forestation and human predation pushed the animals eastwards to the semi-deserts of central Asia. </p>
<p>The wild ancestor of today’s domestic horses (Equus ferus) <a href="http://www.cam.ac.uk/research/news/mystery-of-the-domestication-of-the-horse-solved">was first domesticated in the western Eurasian Steppe</a>, an area where the <a href="http://www.cam.ac.uk/research/news/mystery-of-the-domestication-of-the-horse-solved">earliest archaeological evidence for domesticated horses was found</a>. Recent research also shows the <a href="http://phys.org/news/2016-05-history-eurasian-wild-horses.html">domestic herds were repeatedly restocked with wild horses as they spread across Eurasia</a>. </p>
<p>Horses were initially kept as a food animal, but their full potential as a means of transport, communication and warfare resulted in them being of increasing importance in the <a href="http://www.equineheritageinstitute.org/shaping-civilizations-the-role-of-the-horse-in-human-societies/">development of human civilisation</a>. In Mongolia, <a href="http://www.amnh.org/explore/science-bulletins/bio/documentaries/the-last-wild-horse-the-return-of-takhi-to-mongolia/article-the-horse-in-mongolian-culture">the land of the horse</a>, the legendary 13th-century warlord <a href="http://afe.easia.columbia.edu/mongols/conquests/khans_horses.pdf">Genghis Khan used the animal to establish a domain</a> that extended from Hungary to Korea, and from Siberia to Tibet: an Asian empire won on horseback. </p>
<p>So, if horses were so important to human civilisation, why not the zebra? <a href="http://news.nationalgeographic.com/news/2007/07/070718-african-origin.html">Humans originated in Africa</a> so it seems strange that they missed exploiting such a potentially useful animal living on the same continent. </p>
<p>Unlike the Equids of Eurasia, however, the zebra population of Africa was relatively secure and particularly well adapted to its environment. All equids are herbivorous prey species with a <a href="http://www.cfsph.iastate.edu/Emergency-Response/Just-in-Time/08-Animal-Behavior-Restraint-Equine-HANDOUT.pdf">well developed “flight or fight” response</a>. But to survive in an environment where there is an abundance of large predators including lions, cheetahs and hyenas, the zebra evolved into a particularly alert, responsive animal that flees in the face of danger but also possesses a powerful response if captured. </p>
<p>The <a href="http://www.bbc.co.uk/newsround/14407260">kick of a zebra</a> can break a lion’s jaw. They can be <a href="http://www.nbcwashington.com/news/local/Zebra-Bites-Zookeeper-at-National-Zoo-232342411.html">savage biters</a> and possess a <a href="http://mentalfloss.com/article/80999/14-zany-facts-about-zebras">“ducking” reflex</a> that helps them avoid being caught by lasso. Familiarity with human hunter gatherers may also have fostered a strong avoidance response in the zebra.</p>
<p>All of this means that zebra are not really “people friendly” and as a species they do not fit the criteria for domestication. According to the English explorer and polymath Francis Galton (a relative of Charles Darwin), <a href="http://www.galton.org/essays/1860-1869/galton-1865-domestication-animals.pdf">these requirements</a> include displaying a desire for comfort, being easy to tend, being useful and showing a fondness for man. </p>
<p>Galton uses the zebra as an example of an unmanageable species, stating that the Dutch Boers repeatedly tried to break zebra to harness. Although they had some success, the wild, mulish nature of the animals would frequently break out and thwart their efforts. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/137567/original/image-20160913-4980-1502nie.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/137567/original/image-20160913-4980-1502nie.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/137567/original/image-20160913-4980-1502nie.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/137567/original/image-20160913-4980-1502nie.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/137567/original/image-20160913-4980-1502nie.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/137567/original/image-20160913-4980-1502nie.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/137567/original/image-20160913-4980-1502nie.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">
<figcaption>
<span class="caption">Ride me? Bite me.</span>
<span class="attribution"><a class="source" href="http://www.shutterstock.com/pic-21179662/stock-photo-a-zebra-stallion-shows-his-teeth.html?src=0tyMMW2BsOgISoCak7Dslw-3-29">Shutterstock</a></span>
</figcaption>
</figure>
<p>Although it appears <a href="http://www.dailymail.co.uk/news/article-2763629/Your-eyes-not-deceiving-This-girl-really-riding-think-Prepare-amazed-magic-THE-ZEBRA-WHISPERER.html">possible to tame</a> individual zebra, this species was not a good candidate for domestication. In addition to the intractable nature of the zebra and its strong survival instinct, the fact that this species is “lion fodder” may also have made them appear less attractive “partners” to early humans. </p>
<p>Domestication and selective breeding will <a href="http://www.academia.edu/1785218/From_wild_horses_to_domestic_horses_a_European_perspective">undoubtedly have changed</a> both the physical and behavioural characteristics of the horse, which during the early stages would probably have been smaller, wilder and more similar to the zebra than today’s horse. </p>
<p>And while horses may work harder, live in more urbanised environments and do the bidding of their owners, they also lead safer, more comfortable lives. Domestication saved the horse from extinction. In fact, as a survival strategy, domestication has certainly worked for the global horse population, which numbers 60m.</p>
<p>By contrast, zebra numbers are probably now fewer than 800,000, with humans posing the greatest threat to their survival. Faced with these facts, which would you rather be?</p><img src="https://counter.theconversation.com/content/65018/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Carol Hall 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>They look like stripey horses – so why don’t we ride them?Carol Hall, Reader in Equitation Science, Nottingham Trent UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/561132016-03-11T15:02:36Z2016-03-11T15:02:36ZWhy dog breeds aren’t considered separate species<figure><img src="https://images.theconversation.com/files/114740/original/image-20160310-26248-1dlu2cu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Susan Schmitz / shutterstock</span></span></figcaption></figure><p>Dog owners might disagree, but as far as evolutionary biologists are concerned, all dogs are just dogs. It may seem odd that <em>Canis (lupus) familiaris</em> extends from rabbit-sized Chihuahuas to Great Danes which can be almost the size of a small pony, whereas seemingly much smaller differences place many animals into separate species or sub-species. One has to dig a bit into evolutionary theory for this to make sense.</p>
<p>The dog is <a href="http://www.pbs.org/wgbh/evolution/library/01/5/l_015_02.html">a direct descendant</a> of the grey wolf (<em>Canis lupus</em>), with evidence that lots of different wolves fed into the dog gene pool over the years. In the course of dog domestication, their behaviour, morphology and physique has changed, and differences among dog breeds are indeed astonishing. Imagine if future palaeontologists were to find Chihuahua remains in the fossil record: this animal would appear to have little in common with wolves. </p>
<p>But these differences among dog breeds – and between dogs and wolves – aren’t enough to warrant recognition as distinct species. Dogs are simply too young, from an evolutionary perspective.</p>
<p>It usually takes hundreds of thousands of years or more for mammals to evolve into distinct new species, requiring the slow accumulation of mutations that cause inheritable changes to its physical characteristics – or “phenotype”. Archaeological data and analysis of DNA from today’s dogs and wolves, as well as ancient remains, suggest that domestication started about <a href="http://dx.doi.org/10.1016/j.cub.2015.04.019">16,000-40,000 years ago</a>, with most current dog breeds originating in the past 200 years.</p>
<h2>We’ve sped up dog evolution – but not enough</h2>
<p>Charles Darwin pointed out that humans have accelerated the process of selection by choosing particular individuals for breeding, based on certain desired characteristics – what we call <a href="http://evolution.berkeley.edu/evolibrary/article/evo_30">artificial selection</a>. Natural selection generally requires much more time, because it acts on novel variants introduced into the gene pool through the slow process of chance DNA mutation. Nevertheless, the power of artificial selection in generating extreme phenotypes does not change the fundamental fact that dog breeds have been separated for only a short evolutionary time.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/114774/original/image-20160311-11288-mfueq9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/114774/original/image-20160311-11288-mfueq9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/114774/original/image-20160311-11288-mfueq9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=504&fit=crop&dpr=1 600w, https://images.theconversation.com/files/114774/original/image-20160311-11288-mfueq9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=504&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/114774/original/image-20160311-11288-mfueq9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=504&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/114774/original/image-20160311-11288-mfueq9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=633&fit=crop&dpr=1 754w, https://images.theconversation.com/files/114774/original/image-20160311-11288-mfueq9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=633&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/114774/original/image-20160311-11288-mfueq9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=633&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Great Dane, meet Chihuahua. You have lots in common.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Big_and_little_dog_1.jpg">Ellen Levy Finch</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>This means that dog breeds differ drastically in their appearance and other characteristics, while most of their genomes are still very much alike. Comparing different breeds, most of their genomes indeed show only little differentiation. In other words, Chihuahuas and Great Danes are overall very similar to one another. The vast physical differences are largely driven by relatively few loci (regions) in the genome. These loci have a large phenotypic effect, leading to strong differentiation among breeds. </p>
<p>This is particularly interesting for evolutionary biologists, and pinpointing such regions in the genome has for example recovered the genetic basis of <a href="http://www.nature.com/news/2006/061009/full/news061009-12.html">size variation among dog breeds</a>. We now also have an understanding of the mutations that control traits such as <a href="http://science.sciencemag.org/content/326/5949/150">coat characteristics</a> and <a href="http://bmcgenomics.biomedcentral.com/articles/10.1186/s12864-015-1702-2">ear floppiness</a>.</p>
<h2>Dog breeds are artificial and potentially temporary</h2>
<p>So if breeds are that similar to one another in their genomes, how are the vast differences maintained? The obvious answer is the mating pattern we impose on our dogs – we keep breeds separate by preventing interbreeding between them. </p>
<p>The fact humans keep them apart is crucial here. Species are <a href="http://darwiniana.org/mayrspecies.htm">commonly defined</a> as “groups of interbreeding natural populations that are reproductively isolated from other such groups”. This requires hybrids between distinct species to either be non-viable (such as the proposed “humanzee”), or for their offspring to be infertile like most mules, or the more exotic “ligers”. In both these cases there would be complete reproductive isolation between the two groups, whether they be humans and chimps, lions and tigers, or Labradors and poodles.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/114838/original/image-20160311-11274-1troby6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/114838/original/image-20160311-11274-1troby6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/114838/original/image-20160311-11274-1troby6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/114838/original/image-20160311-11274-1troby6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/114838/original/image-20160311-11274-1troby6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/114838/original/image-20160311-11274-1troby6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/114838/original/image-20160311-11274-1troby6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/114838/original/image-20160311-11274-1troby6.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">Labrador (right) + poodle = the fluffy and fertile labradoodle (left).</span>
<span class="attribution"><span class="source">Bildagentur Zoonar GmbH / shutterstock</span></span>
</figcaption>
</figure>
<p>Yet two entirely different dogs will produce perfectly fertile offspring, and many modern breeds in fact originated in this way. Of course in some cases other factors might make mating very tricky. A female Chihuahua would have trouble naturally delivering a male Great Dane’s offspring, for instance. But though some breeds would never mate with each other without human intervention, middle-sized breeds could provide the link between extremely large and small dogs. </p>
<p>Street dogs are a vivid illustration of this point – they show how the distinct gene pools of dog breeds can rapidly mix once the restrictions of artificial breeding are removed. Moscow’s <a href="https://theconversation.com/how-did-moscows-stray-dogs-learn-to-navigate-the-metro-54790">famous feral dogs</a> have existed separate from purebred pets for at least 150 years now. In this time they have largely lost features like the spotty colouration that distinguish one breed from another, or the wagging tails and friendly behaviour towards humans that distinguish dogs from wolves.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/114777/original/image-20160311-11302-b7aky3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/114777/original/image-20160311-11302-b7aky3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/114777/original/image-20160311-11302-b7aky3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=343&fit=crop&dpr=1 600w, https://images.theconversation.com/files/114777/original/image-20160311-11302-b7aky3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=343&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/114777/original/image-20160311-11302-b7aky3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=343&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/114777/original/image-20160311-11302-b7aky3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=430&fit=crop&dpr=1 754w, https://images.theconversation.com/files/114777/original/image-20160311-11302-b7aky3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=430&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/114777/original/image-20160311-11302-b7aky3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=430&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Left to their own devices, street dogs soon stop looking like distinct breeds.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/akras/2299311609/in/album-72157604174353563/">Andrey</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>So genetic exchange would still be common among dog breeds, were they allowed to reproduce freely. In that sense, dog breeds would not be classified as separate species under most definitions. If those Chihuahuas and Great Danes don’t look like the same species right now, it’s only because humans are constantly maintaining a barrier between them.</p><img src="https://counter.theconversation.com/content/56113/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Frank Hailer 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>We’ve bred them into all shapes and sizes, but dogs haven’t been around for long enough to have evolved beyond Canis familiaris.Frank Hailer, Lecturer in Evolutionary Biology, Cardiff UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/558852016-03-09T12:54:53Z2016-03-09T12:54:53ZA scientist at Crufts: why this dog show is more than a canine beauty pageant<p>Every year, the NEC in Birmingham, England, becomes a magnet for dog lovers, as more than <a href="http://www.expressandstar.com/entertainment/2016/03/08/crufts-2016-when-does-it-start-what-are-the-top-events-your-guide-to-the-125th-anniversary-of-the-birmingham-nec-show/">22,000 canines assemble</a> for Crufts. Founded by travelling dog-food salesman <a href="http://www.crufts.org.uk/content/show-information/history-of-crufts/">Charles Cruft in 1891</a>, Crufts has become one of the world’s largest and most prestigious dog events. Here, you can meet dogs of every shape and size, see inspiring human-dog partnerships and shop for all things dog-related. There’s always a fascinating mix of people in attendance – and this year, I get to be among them. </p>
<p>So what is it about Crufts I find so enthralling? Well, far from being a beauty pageant for pampered pooches, these days Crufts is a celebration of all things canine – and for a self-confessed “dog person” like me, that’s an exciting prospect. But more importantly, Crufts challenges me to reflect on the bond between humans and dogs from a scientific perspective. </p>
<h2>Best of friends</h2>
<p>There is no doubt that humans and dogs have a prolonged <a href="http://science.sciencemag.org/content/276/5319/1687">evolutionary relationship</a>. Since dogs were first domesticated, humans have selectively bred them to bring out particular <a href="http://bmcevolbiol.biomedcentral.com/articles/10.1186/1471-2148-8-28">physical and behavioural</a> characteristics. Selective breeding has resulted in the wide diversity of about 400 pedigree dog breeds recognised today, from the diminutive Chihuahua to the Great Dane. But sadly, many pedigree dog breeds suffer from defects and diseases, which affect their welfare and longevity – these are often a consequence of <a href="http://www.sciencedirect.com/science/article/pii/S1090023311002309?np=y">inbreeding</a>. </p>
<p>Yet it seems that science is coming to the rescue of our doggy companions. Recent research has shown that rates of inbreeding in many pedigree dogs are actually declining <a href="http://cgejournal.biomedcentral.com/articles/10.1186/s40575-015-0027-4">from a high in the 1980s and 1990s</a>. This suggests that dog breeders are becoming better informed, and improving their practices. For example, genetic tests are now used by many dog breeders, to ensure that breeding animals are genetically healthy. </p>
<p>Crufts provides an ideal place to <a href="http://cgejournal.biomedcentral.com/articles/10.1186/s40575-015-0014-9">educate and inform</a> dog owners, breeders and puppy hunters about the value of such health tests. Increasing our awareness of issues associated with all dog breeds – including “designer” cross-breeds such as <a href="http://dogtime.com/dog-breeds/cockapoo">cockapoos</a> and <a href="http://www.labradoodle.org.uk/">labradoodles</a> – can only improve quality of life for both dog and owner. </p>
<h2>Health kick</h2>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/114450/original/image-20160309-13693-1y65awd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/114450/original/image-20160309-13693-1y65awd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=747&fit=crop&dpr=1 600w, https://images.theconversation.com/files/114450/original/image-20160309-13693-1y65awd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=747&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/114450/original/image-20160309-13693-1y65awd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=747&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/114450/original/image-20160309-13693-1y65awd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=939&fit=crop&dpr=1 754w, https://images.theconversation.com/files/114450/original/image-20160309-13693-1y65awd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=939&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/114450/original/image-20160309-13693-1y65awd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=939&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Out and about.</span>
<span class="attribution"><span class="source">from www.shutterstock.com</span></span>
</figcaption>
</figure>
<p>The deep bond between people and their dogs is also demonstrated in a wide range of canine activities at Crufts: from the frenetic relay races of flyball, to the precise movements of dog and handler in obedience. These activities offer a physical and mental challenge for dogs and owners alike. And with rising levels of <a href="https://theconversation.com/its-a-dogs-life-when-mans-best-friend-becomes-his-fattest-5657">canine obesity</a> mirroring that of the <a href="http://www.bmj.com/content/333/7581/1261">human population</a>, strategies to improve <a href="http://www.sciencedirect.com/science/article/pii/S1469029216300048">physical activity levels</a> for both species will be of significant mutual benefit. </p>
<p>Crufts offers a great platform to promote schemes such as “<a href="http://www.thekennelclub.org.uk/activities/get-fit-with-fido/">Get Fit with Fido</a>” – a weight loss competition run by the Kennel Club. Research suggests that many pet dogs aren’t walked daily, so showcasing mutually enjoyable physical activities, such as agility training, might just encourage some dog owners to get a little more active with their pets.</p>
<p>The activities at Crufts can help us to understand the science behind what makes a good canine athlete: from gundogs, to “dancing” dogs in the canine freestyle event, to world-class agility dogs. In fact, <a href="http://www.sciencedirect.com/science/article/pii/S0376635714002538">canine performance science</a> is a rapidly growing area of interest, encompassing genetic selection, puppy rearing, training, housing, handling and health for working dogs. Crufts visitors will see many dogs trained using methods which have been improved by <a href="http://www.sciencedirect.com/science/article/pii/S0168159114000264">new insights into canine learning</a> – a simple way that science has contributed to canine welfare. </p>
<h2>Two way street</h2>
<p>Yet this relationship goes both ways: in fact, dogs can be credited with providing many human health benefits, beyond the customary “walkies”. </p>
<p>Dog owners report higher levels of perceived health than non-dog owners, and <a href="http://www.sciencedirect.com/science/article/pii/S155878781400118X">were found to have</a> more vitality, and better social lives and mental health. One famous study even suggested that <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1422527/pdf/pubhealthrep00128-0003.pdf">dog owners lived longer after a heart attack</a> than non-dog owners. Whether this is a genuine effect of pet ownership, or a sign that people who own pets tend to have a particular personality type, has not been established – but it remains an area of fascination for those interested in the human-dog relationship. </p>
<p>Of course, assistance dogs such as guide dogs, hearing dogs and mobility dogs <a href="http://www.sciencedirect.com/science/article/pii/S1936657415000989">are essential companions and lifesavers</a>. What’s more, anecdotal reports of dogs signalling to their owners the onset of <a href="http://online.liebertpub.com/doi/abs/10.1089/acm.2008.0288">diabetic hypoglycaemic attacks</a> or <a href="http://ac.els-cdn.com/S0920121111003275/1-s2.0-S0920121111003275-main.pdf?_tid=079b800a-e489-11e5-b6ad-00000aab0f27&acdnat=1457371469_aee7c29e31b7764f657df50c29b3bc23">epileptic fits</a> have been confirmed by scientific study. So-called “therapy pets” play a valuable role in homes, hospices and hospitals, making patients happier and acting as non-judgemental confidants. Some dogs have even been trained to <a href="http://www.sciencedirect.com/science/article/pii/S002253471404573X">detect prostate cancer</a>, putting a whole new spin on the “lab test”. </p>
<p>Many organisations involved in the training of these dogs are represented at Crufts, and the “<a href="http://www.crufts.org.uk/content/eukanuba-friends-for-life-2016/">Friends for Life</a>” award recognises their exceptional bravery, support and companionship. There is no doubt about it: we humans share a special connection with our canine companions. And Crufts is the perfect place to celebrate it.</p><img src="https://counter.theconversation.com/content/55885/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jacqueline Boyd is a member of The Kennel Club's Activities Health and Welfare Sub-Group and is employed as a lecturer in Animal Science by Nottingham Trent University.
</span></em></p>An animal science expert explains why Crufts teaches us so much about man’s best friend.Jacqueline Boyd, Lecturer in Animal Science, Nottingham Trent UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/492712015-10-20T10:04:19Z2015-10-20T10:04:19ZNew DNA analysis says your pooch’s ancestors were Central Asian wolves<figure><img src="https://images.theconversation.com/files/98931/original/image-20151019-23275-1b3yqz5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">You've come a long way, baby.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/moggafogga/17145148895">moggafogga</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span></figcaption></figure><p>Dogs’ origin story goes something like this: sometime between 16,000 and 30,000 years ago, there were some stressed-out hungry wolves whose hunting territory had been encroached upon by humans. Luckily, these wolves were resourceful and they noticed human beings have a tendency to leave delicious things lying around. Scavenging leftovers seemed significantly easier than going out and hunting, so they hung around the people.</p>
<p>Wolves make unnerving neighbors. However, some are less unnerving than others. The humans were a lot more inclined to tolerate the proximity of less aggressive, more people-oriented wolves. As an added bonus, other predators are less likely to harass you when you are surrounded by wolves. So the people and the nicest wolves came to an agreement – the people tolerated and fed the tamest and most helpful wolves.</p>
<p>Smart, tame wolves have smarter, tamer wolf cubs, and so over time the wolves became more and more pleasant to have around. Obviously, friendly, helpful wolves hanging around people and eating leftovers aren’t really wolves; we have a word for those things – they’re dogs.</p>
<p>That’s biologists’ reasonable guess for <em>how</em> dogs came about. We have some idea <em>when</em> it all happened, but it’s been harder to figure out <em>where</em>. Who first took in scavenging gray wolves and turned them into dogs?</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/98937/original/image-20151019-23257-1ycv68u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/98937/original/image-20151019-23257-1ycv68u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/98937/original/image-20151019-23257-1ycv68u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/98937/original/image-20151019-23257-1ycv68u.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/98937/original/image-20151019-23257-1ycv68u.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/98937/original/image-20151019-23257-1ycv68u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/98937/original/image-20151019-23257-1ycv68u.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/98937/original/image-20151019-23257-1ycv68u.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">Dogs still know a good thing when they see it – warmth and food with people ‘round the campfire.</span>
<span class="attribution"><a class="source" href="http://www.shutterstock.com/pic-156781970/stock-photo-dog-near-campfire-with-boiled-tea-in-autumn-forest.html">Camping image via www.shutterstock.com.</a></span>
</figcaption>
</figure>
<h2>Investigating this wheredunit</h2>
<p>Scientists have looked at <a href="http://doi.org/10.1093/molbev/msp195">DNA inherited exclusively from the mother</a> (called mitochondrial) and <a href="http://doi.org/10.1038/hdy.2011.114">DNA inherited exclusively from the father</a> (the Y-chromosome) and suggested that dogs were first domesticated in China, south of the Yangtze River.</p>
<p>However, the oldest dog bones anyone has found are from the other end of Eurasia, all the way in Northern Europe. Furthermore, the mitochondria of modern dogs are closely related to the mitochondria of <a href="http://doi.org/10.1126/science.1243650">ancient European wolves</a>.</p>
<p>Finally, Middle Eastern wolves share the most genetic sequences with today’s dogs, which makes it seem like <a href="http://doi.org/10.1038/nature08837">maybe Middle Eastern wolves</a> are the ancestral wolf population.</p>
<p>All these threads of evidence broadly agree that dogs are from somewhere in Eurasia. But my colleagues and I wanted to narrow that down a bit – and to do that, we decided we needed DNA from at as many dogs as possible <a href="http://doi.org/10.1073/pnas.1516215112">for our new study</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/98924/original/image-20151019-23260-sh77f9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/98924/original/image-20151019-23260-sh77f9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/98924/original/image-20151019-23260-sh77f9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/98924/original/image-20151019-23260-sh77f9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/98924/original/image-20151019-23260-sh77f9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/98924/original/image-20151019-23260-sh77f9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/98924/original/image-20151019-23260-sh77f9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/98924/original/image-20151019-23260-sh77f9.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">Team members sampling a village dog in the Pacific Islands.</span>
<span class="attribution"><span class="source">Adam Boyko</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Modern dogs cover the globe</h2>
<p>Dogs are found almost everywhere people are, and over time we have bred them to do everything from guarding livestock to going fishing. The breeds we’ve created come in many shapes and sizes, ranging from tiny Chihuahuas to giant Great Danes. The vast <a href="http://doi.org/10.1073/pnas.1203005109">majority of these breeds</a> are less than 200 years old and come from Europe. But these purebred dogs or even mixes of these breed dogs are the minority of dogs on the planet.</p>
<p>Most dogs are free-ranging village dogs, which live around and among people but aren’t necessarily what you’d think of as pets. You can learn more about ancient dogs by studying these village dogs (as compared to studying breed dogs) because village dogs have more genetic diversity; the number of different versions of the same genes in village dogs is higher than it is in breed dogs. </p>
<p>All dogs were formed from a select group of wolves, and therefore have a subset of the genetic diversity found in wolves. But breeds were formed from a subset of dogs so they have only a further subset of the diversity found in dogs.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/98938/original/image-20151019-23249-1u2jeii.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/98938/original/image-20151019-23249-1u2jeii.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/98938/original/image-20151019-23249-1u2jeii.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/98938/original/image-20151019-23249-1u2jeii.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/98938/original/image-20151019-23249-1u2jeii.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/98938/original/image-20151019-23249-1u2jeii.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/98938/original/image-20151019-23249-1u2jeii.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/98938/original/image-20151019-23249-1u2jeii.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>
<figcaption>
<span class="caption">In the cradle of dogkind?</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/pirateparrot/229962390">Coss and Johanna</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span>
</figcaption>
</figure>
<h2>Tracing the trail through DNA sequences</h2>
<p>Members of our lab traveled to collect blood or spit from dogs in a variety of locales, and collaborators sent us fluids from places to which we didn’t manage to travel. Village dogs are fairly easy to find for researchers carrying food. In total, we extracted DNA from the fluids of 549 dogs from 38 countries spanning the majority of the globe as well as 4,676 purebred dogs. Our lab at Cornell is conveniently located in the same building as a veterinary hospital, so most of our purebred dogs were patients.</p>
<p>Once we had our samples, we then determined each dog’s genotype at about 180,000 distinct points in the genome. This is the largest data set anyone has used to address the question of dog origins so far.</p>
<p>We were looking for a very specific pattern of historical genetic diversity. When a select group of wolves became dogs, those dogs contained only the genetic diversity present in that subset of wolves. When people took some of the dogs and moved on to new regions of the globe, or traded dogs with people in other regions, they took only a subset of the total dogs, and by extension a subset of the total diversity.</p>
<p>Therefore, we expect the original population of dogs to be the most diverse. There would be a gradient of decreasing diversity in all populations as they move away from the center of origin.</p>
<p>And this is the pattern we observed when we compared the genetics of dogs from different populations. Dogs from Central Asia, Mongolia and Nepal are the most diverse, with genomes that correspond to the early, original variation in the population right after domestication happened. When we look at the same DNA markers in dogs from neighboring regions, diversity decreases. It decreases further corresponding to the location’s increasing distance from Central Asia. This is the pattern we would expect if the people who first took in scavenging gray wolves and turned them into dogs were located in Central Asia.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/98925/original/image-20151019-23257-17j4zqz.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/98925/original/image-20151019-23257-17j4zqz.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/98925/original/image-20151019-23257-17j4zqz.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/98925/original/image-20151019-23257-17j4zqz.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/98925/original/image-20151019-23257-17j4zqz.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/98925/original/image-20151019-23257-17j4zqz.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/98925/original/image-20151019-23257-17j4zqz.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/98925/original/image-20151019-23257-17j4zqz.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">Even dogs we sampled in the Pacific Islands traced their forebears back to Central Asia.</span>
<span class="attribution"><span class="source">Adam Boyko</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Looking at the largest data set of dogs amassed so far, we observe a very clear signal that most dogs alive today descended from dogs in Central Asia. However, we only looked at dogs alive right now. We have no information about historical populations of dogs that have no living descendants. Furthermore, the patterns of diversity we observe are reflective of the origins of dogs but also of everything that has happened to dog populations since domestication.</p>
<p>Other research groups are extracting DNA from bones of ancient dogs, and these sequences will provide exciting new insights from time points closer to domestication. However, ancient DNA studies are limited by the availability of ancient dog bones – which is affected by many factors other than the distribution of historic populations; for instance, some environments are more conducive to the preservation of bone and DNA than others, some regions have been more extensively investigated by archaeologists than others, and so on. If we see similar patterns in ancient and modern dogs, that will add clarity to the history of dogs and the people who love them.</p><img src="https://counter.theconversation.com/content/49271/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>This project was funded by the National Science Foundation, National Geographic Society Expedition Council, Zoetis Animal Health, Cornell University Center for Advanced Technology, Cornell University, and dozens of PetriDish donors</span></em></p>The how and the when of dog domestication are fairly settled. As for the where: now DNA says Fido traces his roots back to wolves in Central Asia that lingered around people’s camps millennia ago.Laura Shannon, Postdoctoral Research Associate in Biological Sciences, Cornell UniversityLicensed as Creative Commons – attribution, no derivatives.