tag:theconversation.com,2011:/us/topics/human-80708/articlesHuman – The Conversation2023-02-23T13:15:04Ztag:theconversation.com,2011:article/1908702023-02-23T13:15:04Z2023-02-23T13:15:04ZImagination makes us human – this unique ability to envision what doesn’t exist has a long evolutionary history<figure><img src="https://images.theconversation.com/files/510729/original/file-20230216-24-yo82dh.jpg?ixlib=rb-1.1.0&rect=102%2C53%2C3346%2C2522&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Your brain can imagine things that haven't happened or that don't even exist.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/constellation-of-you-royalty-free-image/487364203">agsandrew/iStock via Getty Images Plus</a></span></figcaption></figure><p>You can easily picture yourself riding a bicycle across the sky even though that’s not something that can actually happen. You can envision yourself doing something you’ve never done before – like water skiing – and maybe even imagine a better way to do it than anyone else.</p>
<p>Imagination involves creating a mental image of something that is not present for your senses to detect, or even something that isn’t out there in reality somewhere. Imagination is one of the key abilities that make us human. But where did it come from?</p>
<p><a href="https://scholar.google.com/citations?user=Ury0hsMAAAAJ&hl=en&oi=ao">I’m a neuroscientist</a> who studies how children acquire imagination. I’m especially interested in the neurological mechanisms of imagination. Once we identify what brain structures and connections are necessary to mentally construct new objects and scenes, scientists like me can look back over the course of evolution to see when these brain areas emerged – and potentially gave birth to the first kinds of imagination.</p>
<h2>From bacteria to mammals</h2>
<p>After <a href="https://doi.org/10.1038/s41586-019-1436-4">life emerged on Earth</a> around 3.4 billion years ago, organisms gradually became more complex. Around 700 million years ago, neurons organized into <a href="https://doi.org/10.1242/jeb.110692">simple neural nets</a> that then <a href="https://doi.org/10.1101/gr.874803">evolved into the brain and spinal cord</a> around 525 million years ago.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/510737/original/file-20230216-20-wy383x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Velociraptor chasing a furry critter" src="https://images.theconversation.com/files/510737/original/file-20230216-20-wy383x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/510737/original/file-20230216-20-wy383x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=375&fit=crop&dpr=1 600w, https://images.theconversation.com/files/510737/original/file-20230216-20-wy383x.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=375&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/510737/original/file-20230216-20-wy383x.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=375&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/510737/original/file-20230216-20-wy383x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=471&fit=crop&dpr=1 754w, https://images.theconversation.com/files/510737/original/file-20230216-20-wy383x.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=471&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/510737/original/file-20230216-20-wy383x.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=471&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">It was to mammals’ advantage to hide out while cold-blooded dinosaurs hunted during the day.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/illustration/velociraptor-chasing-a-rat-sized-mammal-royalty-free-illustration/168839736">Daniel Eskridge/Stocktrek Images via Getty Images</a></span>
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<p><a href="https://doi.org/10.1111/j.1469-185X.2009.00094.x">Eventually dinosaurs evolved around 240 million</a> years ago, with <a href="https://doi.org/10.1038/s41586-022-04963-z">mammals emerging a few million years later</a>. While they shared the landscape, dinosaurs were very good at catching and <a href="https://doi.org/10.1080/02724634.2022.2144337">eating small, furry mammals</a>. Dinosaurs were cold-blooded, though, and, like modern cold-blooded reptiles, could only move and hunt effectively <a href="https://doi.org/10.1126/science.1253143">during the daytime when it was warm</a>. To avoid predation by dinosaurs, mammals stumbled upon a solution: <a href="https://doi.org/10.1016/j.ympev.2014.05.016">hide underground during the daytime</a>.</p>
<p>Not much food, though, grows underground. To eat, mammals had to travel above the ground – but the safest time to forage was at night, when dinosaurs were less of a threat. <a href="https://doi.org/10.1038/s41586-022-04963-z">Evolving to be warm-blooded</a> meant mammals could move at night. That solution came with a trade-off, though: Mammals had to eat a lot more food than dinosaurs per unit of weight <a href="https://doi.org/10.1111/brv.12280">in order to maintain their high metabolism</a> and to support their constant inner body temperature around 99 degrees Fahrenheit (37 degrees Celsius).</p>
<p>Our mammalian ancestors had to find <a href="https://doi.org/10.1126/science.1061967">10 times more food</a> during their short waking time, and they had to find it in the dark of night. How did they accomplish this task?</p>
<p>To optimize their foraging, mammals developed a new system to efficiently memorize places where they’d found food: linking the part of the brain that records sensory aspects of the landscape – how a place looks or smells – to the part of the brain that controls navigation. They encoded features of the landscape in the neocortex, the outermost layer of the brain. They encoded navigation in the entorhinal cortex. And the <a href="https://doi.org/10.1038/s41593-018-0189-y">whole system was interconnected</a> by the brain structure called the hippocampus. <a href="https://doi.org/10.1002/hipo.20205">Humans still use this memory system</a> for remembering objects and past events, such as your car and where you parked it.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/510740/original/file-20230216-14-qjt96p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="two bits of human brain are highlighted, one on each side" src="https://images.theconversation.com/files/510740/original/file-20230216-14-qjt96p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/510740/original/file-20230216-14-qjt96p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/510740/original/file-20230216-14-qjt96p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/510740/original/file-20230216-14-qjt96p.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/510740/original/file-20230216-14-qjt96p.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/510740/original/file-20230216-14-qjt96p.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/510740/original/file-20230216-14-qjt96p.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">An interior brain structure called the hippocampus helps synthesize different kinds of information to create memories.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/illustration/hippocampus-of-the-brain-illustration-royalty-free-illustration/1220616079">Sebastian Kaulitzki/Science Photo Library via Getty Images</a></span>
</figcaption>
</figure>
<p><a href="https://doi.org/10.1016/j.conb.2020.03.014">Groups of neurons</a> in the neocortex encode these memories of objects and past events. Remembering a thing or an episode <a href="https://doi.org/10.1037/a0017937">reactivates the same neurons</a> that initially encoded it. All mammals likely can recall and re-experience previously encoded objects and events by reactivating these groups of neurons. This neocortex-hippocampus-based memory system that evolved 200 million years ago became the first key step toward imagination. </p>
<p>The next building block is the capability to construct a “memory” that hasn’t really happened.</p>
<h2>Involuntary made-up ‘memories’</h2>
<p>The simplest form of imagining new objects and scenes happens in dreams. These vivid, bizarre involuntary fantasies are associated in people with the rapid eye movement (REM) stage of sleep.</p>
<p>Scientists hypothesize that species whose rest includes periods of REM sleep <a href="https://doi.org/10.1038/nrn2716">also experience dreams</a>. Marsupial and placental mammals do have REM sleep, but the egg-laying mammal the echidna does not, suggesting that this stage of the sleep cycle <a href="https://www.worldcat.org/title/317118257">evolved after these evolutionary lines diverged</a> 140 million years ago. In fact, recording from specialized neurons in the brain called <a href="https://doi.org/10.1146/annurev.neuro.31.061307.090723">place cells</a> demonstrated that animals can “dream” of going <a href="https://doi.org/10.7554/eLife.06063">places they’ve never visited before</a>.</p>
<p>In humans, solutions found during dreaming can <a href="https://doi.org/10.1038/nature02223">help solve problems</a>. There are numerous examples of scientific and engineering solutions spontaneously visualized during sleep.</p>
<p>The neuroscientist Otto Loewi dreamed of an experiment that proved nerve impulses are <a href="https://www.nobelprize.org/prizes/medicine/1936/loewi/facts/">transmitted chemically</a>. He immediately went to his lab to perform the experiment – later receiving the Nobel Prize for this discovery.</p>
<p>Elias Howe, the inventor of the first sewing machine, claimed that the main innovation, placing the thread hole near the tip of the needle, <a href="https://dreamsocial.co/famous-dreams-sewing-machine/">came to him in a dream</a>. </p>
<p>Dmitri Mendeleev described seeing in a dream “<a href="https://doi.org/10.1038/35046170">a table where all the elements fell into place as required</a>. Awakening, I immediately wrote it down on a piece of paper.” And that was the periodic table.</p>
<p>These discoveries were enabled by the same mechanism of involuntary imagination first acquired by mammals 140 million years ago.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/510741/original/file-20230216-14-qmauaf.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="young professionals looking at glass wall with post-it notes" src="https://images.theconversation.com/files/510741/original/file-20230216-14-qmauaf.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/510741/original/file-20230216-14-qmauaf.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/510741/original/file-20230216-14-qmauaf.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/510741/original/file-20230216-14-qmauaf.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/510741/original/file-20230216-14-qmauaf.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/510741/original/file-20230216-14-qmauaf.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/510741/original/file-20230216-14-qmauaf.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">Intentionally brainstorming ideas depends on being able to control your imagination.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/diverse-businesspeople-smiling-while-having-a-royalty-free-image/1453986826">Goodboy Picture Company/E+ via Getty Images</a></span>
</figcaption>
</figure>
<h2>Imagining on purpose</h2>
<p>The difference between voluntary imagination and involuntary imagination is analogous to the difference between voluntary muscle control and muscle spasm. Voluntary muscle control allows people to deliberately combine muscle movements. Spasm occurs spontaneously and cannot be controlled.</p>
<p>Similarly, voluntary imagination allows people to deliberately combine thoughts. When asked to mentally combine two identical right triangles along their long edges, or hypotenuses, you envision a square. When asked to mentally cut a round pizza by two perpendicular lines, you visualize four identical slices.</p>
<p>This deliberate, responsive and reliable capacity to combine and recombine mental objects is called prefrontal synthesis. It relies on the ability of the prefrontal cortex located at the very front of the brain to control the rest of the neocortex.</p>
<p>When did our species acquire the ability of prefrontal synthesis? Every artifact dated before 70,000 years ago could have been made by a creator who lacked this ability. On the other hand, starting about that time there are various archeological artifacts unambiguously indicating its presence: composite figurative objects, such as <a href="https://doi.org/10.1038/425007a">lion-man</a>; <a href="https://doi.org/10.1016/j.jas.2007.11.006">bone needles with an eye</a>; <a href="https://doi.org/10.1016/j.jas.2011.04.001">bows and arrows</a>; <a href="https://doi.org/10.1016/j.jhevol.2012.03.003">musical instruments</a>; <a href="https://onlinelibrary.wiley.com/doi/pdfdirect/10.1002/gea.20163">constructed dwellings</a>; <a href="https://doi.org/10.1177/0392192107077649">adorned burials suggesting the beliefs in afterlife</a>, and many more. </p>
<p>Multiple types of archaeological artifacts unambiguously associated with prefrontal synthesis appear simultaneously around 65,000 years ago in multiple geographical locations. This abrupt change in imagination has been characterized by historian Yuval Harari as the “<a href="https://www.penguin.co.uk/books/437186/sapiens-by-yuval-noah-harari/9781784873646">cognitive revolution</a>.” Notably, <a href="https://doi.org/10.1016/j.ajhg.2009.05.001">it approximately coincides with</a> the largest <a href="https://doi.org/10.1086/375120"><em>Homo sapiens</em>‘ migration out of Africa</a>.</p>
<p><a href="https://doi.org/10.1098/rspb.2009.1473">Genetic analyses suggest</a> that a few individuals acquired this prefrontal synthesis ability and then spread their genes far and wide by eliminating other contemporaneous males with the use of an imagination-enabeled strategy and newly developed weapons.</p>
<p>So it’s been a journey of many millions of years of evolution for our species to become equipped with imagination. Most nonhuman mammals have potential for imagining what doesn’t exist or hasn’t happened involuntarily during REM sleep; only humans can voluntarily conjure new objects and events in our minds using prefrontal synthesis.</p><img src="https://counter.theconversation.com/content/190870/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Andrey Vyshedskiy 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>By learning what parts of the brain are crucial for imagination to work, neuroscientists can look back over hundreds of millions of years of evolution to figure out when it first emerged.Andrey Vyshedskiy, Professor of Neuroscience, Boston UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1937642022-11-03T15:51:51Z2022-11-03T15:51:51ZNeanderthals: how a carnivore diet may have led to their demise<figure><img src="https://images.theconversation.com/files/493286/original/file-20221103-24-3lijt3.jpg?ixlib=rb-1.1.0&rect=34%2C60%2C5716%2C3768&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">3D rendering of an Neanderthal man</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-illustration/prehistoric-early-man-neanderthal-3d-rendering-1746110927">RaveeCG/Shutterstock</a></span></figcaption></figure><p>Imagine that you have an unhealthy interest in your neighbours’ lives. Unable to ask them directly, you rifle through their rubbish bins. You find the bones of cooked chickens and try and work out what else they eat.</p>
<p>This is a bit like how archaeologists <a href="https://researchonline.ljmu.ac.uk/id/eprint/12696/1/Buck%20&%20Stringer,%202014_Submission.pdf">study the diets</a> of extinct humans such as the Neanderthals and early homo sapiens. This is about more than satisfying curiosity. Understanding our ancestors’ diets <a href="https://www.ucl.ac.uk/human-evolution/news/2017/mar/neanderthal-behaviour-diet-and-disease-inferred-ancient-dna-dental-calculus">may reveal critical clues</a> about their evolutionary success or failure.</p>
<p>A recent study <a href="https://www.pnas.org/doi/10.1073/pnas.2109315119">which analysed zinc</a> from the tooth of a Neanderthal from Spain reveals they were mainly carnivores, wherever they lived. This discovery helps explain why they became extinct. </p>
<p>Neanderthals dominated <a href="https://www.nhm.ac.uk/discover/who-were-the-neanderthals.html">Europe and western Asia</a> during the last 200,000 years of the Ice Age, while homo sapiens were developing in Africa. Their remains and characteristic stone tools are abundant across Europe and the near East, and in smaller numbers as far east as Tadjikistan (which shares a border with China).</p>
<p>The Neanderthals lived in the heartlands of the <a href="https://www.cms.int/sites/default/files/publication/fact_sheet_eurasian_steppe_climate_change.pdf">Eurasian steppes</a> (the largest grassland in the world, extending from Hungary to China), an area not rich in nutritional vegetables. But <a href="https://books.ub.uni-heidelberg.de/propylaeum/catalog/book/868?lang=en">surveys of their campsites</a> have revealed they ate nuts, fruits, mushrooms, shellfish and other food that can be easily gathered. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/493239/original/file-20221103-24-103iha.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/493239/original/file-20221103-24-103iha.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=557&fit=crop&dpr=1 600w, https://images.theconversation.com/files/493239/original/file-20221103-24-103iha.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=557&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/493239/original/file-20221103-24-103iha.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=557&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/493239/original/file-20221103-24-103iha.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=700&fit=crop&dpr=1 754w, https://images.theconversation.com/files/493239/original/file-20221103-24-103iha.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=700&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/493239/original/file-20221103-24-103iha.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=700&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Cutmarks left by stone tools on this wing bone of a velvet scoter (sea duck), show that.
smaller animals were part of Neanderthals’ diet.</span>
<span class="attribution"><span class="source">Sabine Gaudzinski-Windheuser</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Neanderthals were a species <a href="https://www.ucl.ac.uk/human-evolution/news/2022/feb/unique-foot-posture-neanderthals-reflects-their-body-mass-and-high-mechanical-stress">constantly on the move</a> who needed a high calorie diet. The butchered remains of horse, reindeer, bison and mammoths that Neanderthals left on their campsites reveal they <a href="https://dro.dur.ac.uk/17856/1/17856.pdf">hunted the most dangerous animals</a> in their world. But that doesn’t tell us whether their diets varied from group to group across their massive range.</p>
<h2>Low carb diet</h2>
<p>For the last two decades, advances in <a href="https://www.penn.museum/research/project.php?pid=30">molecular biology</a> have deepened archaeologists’ understanding of early human diets. The cool conditions in northern Europe, such as France and Germany, <a href="https://www.researchgate.net/publication/228431102_Biogeochemical_data_from_well_preserved_200_ka_collagen_and_skeletal_remains">help preserve collagen</a> in fossil bone. With a technique called <a href="https://www.crowcanyon.org/stable-isotope-analysis/">stable isotope analysis</a> we can recover minute amounts of carbon and nitrogen from the collagen in early human bones, and find out where the protein they ate came from. Isotopes are groups of atoms belonging to the same element but have different mass. Studies of these bones’ isotopes have shown Neanderthals in northern Europe got <a href="https://www.pnas.org/doi/full/10.1073/pnas.0903821106">80-90% of their protein</a> from animals. That’s up there with the wolves and hyenas. In the arid southern parts of Europe we’re not so lucky. Collagen in fossil bone easily disintegrates in warmer climates, taking with it the clues to southern Neanderthals’ diets.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/493237/original/file-20221103-19-myadsi.png?ixlib=rb-1.1.0&rect=4%2C2%2C932%2C789&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/493237/original/file-20221103-19-myadsi.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=508&fit=crop&dpr=1 600w, https://images.theconversation.com/files/493237/original/file-20221103-19-myadsi.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=508&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/493237/original/file-20221103-19-myadsi.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=508&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/493237/original/file-20221103-19-myadsi.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=638&fit=crop&dpr=1 754w, https://images.theconversation.com/files/493237/original/file-20221103-19-myadsi.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=638&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/493237/original/file-20221103-19-myadsi.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=638&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The impact from a spear on this pelvic bone of an adult fallow deer shows Neanderthals were hunting with bayonet-style spears around 120,000 years ago.</span>
<span class="attribution"><span class="source">Sabine Gaudzinski-Windheuser.</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>But over the last year archaeologists have found that traces of zinc in Neanderthal bones also preserve information about the diet of the ancient person who they belong to. </p>
<p>Studies over the last few years of zinc isotopes show they have huge potential for unlocking clues about the evolution of life such as the <a href="https://pubmed.ncbi.nlm.nih.gov/29869832/">rise of eukaryotes</a>, a group of organism which humans belong to, and the <a href="https://www.nature.com/articles/s42003-021-02212-z">complexity of marine food</a> webs.</p>
<h2>Expert hunters</h2>
<p>The zinc level in carnivores’ bones is lower than those <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8175341/">of their prey</a>. The difference is not affected by age, sex or decay over time. Zinc ratios can be measured from samples as small as 1mg of bone. Even these tiny amounts allow an accurate assessment of an animal’s place in the food chain when they were alive. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/493240/original/file-20221103-18-qqiknd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/493240/original/file-20221103-18-qqiknd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=899&fit=crop&dpr=1 600w, https://images.theconversation.com/files/493240/original/file-20221103-18-qqiknd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=899&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/493240/original/file-20221103-18-qqiknd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=899&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/493240/original/file-20221103-18-qqiknd.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1130&fit=crop&dpr=1 754w, https://images.theconversation.com/files/493240/original/file-20221103-18-qqiknd.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1130&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/493240/original/file-20221103-18-qqiknd.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1130&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Somewhere between 50,000-60,000 years ago Neanderthals used small handaxes such as this to butcher mammoths at Lynford in eastern England.</span>
<span class="attribution"><span class="source">Mark White</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The recent study’s analysis of zinc from the tooth enamel of a Neanderthal, who lived and died around 150,000 years ago in the Spanish Pyrenees, gives new insights into the diet of ancient humans. Zinc isotopes were analysed from 43 teeth of 12 animal species living in a grassland around the Los Moros I cave in Catalonia, Spain. These included carnivores such as wolf, hyena and dhole (also known as mountain wolf), omnivorous cave bears, and herbivores including ibex, red deer, horse and rabbit. The results brought to life a food web of the Pleistocene steppe, a system of interlocking food chains from plants up to the top carnivores. The zinc in the Neanderthal’s tooth had by far the lowest zinc value in the food web, revealing they were a top level carnivore.</p>
<p>The bone heaps on <a href="https://www.nature.com/articles/s41559-018-0596-1">Neanderthal campsites</a> show they hunted big animals in large numbers. These heaps appear even in areas of the landscape where humans would be at a disadvantage, such as at the edge of water courses. Imagine trying to bayonet an adult bison or horse. Both <a href="https://www.nps.gov/articles/15-facts-about-bison.htm">weigh almost a tonne</a>. The new isotope study reveals Neanderthals’ main survival strategy was to hunt whatever animals could be found wherever they were in the world. Small animals and vegetables probably amounted to little more than side dishes. Their game plan was to shoot first, and answer questions later.</p>
<h2>Broader diets made us more resilient</h2>
<p>Isotopes taken from sites across Europe from remains of the <em>Homo sapiens</em> groups who inherited Pleistocene Eurasia from the Neanderthals <a href="https://www.pnas.org/doi/full/10.1073/pnas.111155298">reveal they had broader dietary</a> range. Plants, birds and fish were main courses for these early humans. The Pleistocene was a the grassland-steppe ecosystem that dominated Siberia during the Pleistocene and disappeared 10,000 years ago. It had a remarkably unstable climate and changed from <a href="https://royalsocietypublishing.org/doi/10.1098/rstb.2003.1436">dry grasslands and wet tundras to coniferous woodlands</a>, constantly shaking up the variety and number of large herbivores grazing there. So an omnivorous diet would have made these people far more resilient than those who relied on big game hunting. We don’t know much about what happened to Neanderthals when big game populations collapsed. If reindeer failed to show, what could they do? But with rapid progress in biomolecular science, I doubt we will have to wait long to find out.</p><img src="https://counter.theconversation.com/content/193764/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Paul Pettitt 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>Zinc in their bones reveal that these early humans were top of the food chain.Paul Pettitt, Professor in the Department of Archaeology, Durham UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1919132022-10-07T12:22:44Z2022-10-07T12:22:44ZOur ‘Homo sapiens’ ancestors shared the world with Neanderthals, Denisovans and other types of humans whose DNA lives on in our genes<figure><img src="https://images.theconversation.com/files/488681/original/file-20221007-12-xnxe5b.jpg?ixlib=rb-1.1.0&rect=22%2C11%2C2320%2C1616&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Hundreds of thousands of years ago, our *Homo sapiens* ancestors shared the landscape with multiple other hominins.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/the-exhibit-hall-includes-more-than-75-skulls-including-two-news-photo/129710842">The Washington Post via Getty Images</a></span></figcaption></figure><p>When the <a href="https://www.livescience.com/how-many-human-species.html">first modern humans arose</a> in East Africa sometime between 200,000 and 300,000 years ago, the world was very different compared to today. Perhaps the biggest difference was that we – meaning people of our species, <em>Homo sapiens</em> – were only one of several types of humans (or <a href="https://australian.museum/learn/science/human-evolution/hominid-and-hominin-whats-the-difference/">hominins</a>) that simultaneously existed on Earth.</p>
<p>From the well-known <a href="https://humanorigins.si.edu/evidence/genetics/ancient-dna-and-neanderthals">Neanderthals</a> and <a href="https://theconversation.com/fresh-clues-to-the-life-and-times-of-the-denisovans-a-little-known-ancient-group-of-humans-110504">more enigmatic Denisovans</a> in Eurasia, to the diminutive <a href="https://theconversation.com/the-hobbits-were-extinct-much-earlier-than-first-thought-56922">“hobbit” <em>Homo floresiensis</em></a> on the island of Flores in Indonesia, to <a href="https://theconversation.com/i-was-part-of-the-team-that-found-the-homo-naledi-childs-skull-how-we-did-it-171153"><em>Homo naledi</em> that lived in South Africa</a>, multiple hominins abounded.</p>
<p>Then, between 30,000 and 40,000 years ago, <a href="https://flexbooks.ck12.org/cbook/ck-12-college-human-biology-flexbook-2.0/section/7.6/primary/lesson/neanderthals-and-other-archaic-humans-chumbio/">all but one type of these hominins disappeared</a>, and for the first time we were alone.</p>
<p>Until recently, one of the mysteries about human history was whether our ancestors interacted and mated with these other types of humans before they went extinct. This fascinating question was the subject of great and often contentious <a href="https://www.sfgate.com/science/article/Neanderthal-love-Scientists-split-over-how-much-2626826.php">debates among scientists for decades</a>, because the data needed to answer this question simply didn’t exist. In fact, it seemed to many that the data would never exist.</p>
<p><a href="https://scholar.google.com/citations?user=_Urs-74AAAAJ&hl=en&oi=ao">Svante Pääbo</a>, however, paid little attention to what people thought was or was not possible. His persistence in developing tools to extract, sequence and interpret ancient DNA enabled sequencing the genomes of <a href="https://doi.org/10.1126/science.1188021">Neanderthals</a>, <a href="https://www.nature.com/articles/nature09710">Denisovans</a> and <a href="https://doi.org/10.1038/nature14558">early modern humans</a> who lived over 45,000 years ago.</p>
<p><a href="https://www.nobelprize.org/prizes/medicine/2022/press-release/">For developing this new field of paleogenomics</a>, Pääbo was awarded the 2022 Nobel Prize in Physiology or Medicine. This honor is not only well-deserved recognition for Pääbo’s triumphs, but also for evolutionary genomics and the insights it can contribute toward a more comprehensive understanding of human health and disease.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/488774/original/file-20221007-24-40vkma.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Diagram of human lineages diverging and interbreeding over time" src="https://images.theconversation.com/files/488774/original/file-20221007-24-40vkma.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/488774/original/file-20221007-24-40vkma.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=621&fit=crop&dpr=1 600w, https://images.theconversation.com/files/488774/original/file-20221007-24-40vkma.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=621&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/488774/original/file-20221007-24-40vkma.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=621&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/488774/original/file-20221007-24-40vkma.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=780&fit=crop&dpr=1 754w, https://images.theconversation.com/files/488774/original/file-20221007-24-40vkma.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=780&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/488774/original/file-20221007-24-40vkma.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=780&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 simplified model of human evolution showing how humans are related to Neanderthals and Denisovans. Arrows between different branches show mating that occurred. Events that happened further back in time are closer to the top of the image.</span>
<span class="attribution"><span class="source">Joshua Akey</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Mixing and mating, revealed by DNA</h2>
<p>Genetic studies of living people over the past several decades revealed the general contours of human history. Our species arose in Africa, dispersing out from that continent around 60,000 years ago, ultimately spreading to nearly all habitable places on Earth. Other types of humans existed as modern humans migrated throughout the world, but the genetic data showed little evidence that modern humans mated with other hominins.</p>
<p>Over the past decade, however, the study of ancient DNA, recovered from fossils up to around <a href="https://www.scientificamerican.com/article/oldest-ancient-human-dna-details-dawn-of-neandertals/">400,000 years old</a>, has revealed startling new twists and turns in the story of human history. </p>
<p>For example, the Neanderthal genome provided the data necessary to definitively show that humans and Neanderthals mated. Non-African people alive today inherited about <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5772775/">2% of their genomes</a> from Neanderthal ancestors, thanks to this kind of interbreeding.</p>
<p>In one of the biggest surprises, when Pääbo and his colleagues sequenced ancient DNA obtained from a small finger bone fragment that was assumed to be Neanderthal, it turned out to be an entirely <a href="https://doi.org/10.1038/nature09710">unknown type of human, now called Denisovans</a>. <a href="https://nautil.us/the-human-family-tree-it-turns-out-is-complicated-238239/">Humans and Denisovans also mated</a>, with the highest levels of Denisovan ancestry present today – between 4% and 6% – in individuals of Oceanic ancestry.</p>
<p>Strikingly, ancient DNA from a 90,000-year-old female revealed that she had <a href="https://doi.org/10.1038/d41586-018-06004-0">a Neanderthal mother and a Denisovan father</a>. Although there are still many unanswered questions, the picture emerging from analyses of ancient and modern DNA is that not only did multiple hominins overlap in time and space, but that matings were relatively common.</p>
<h2>Archaic genes you carry today</h2>
<p>Estimating the proportion of ancestry that modern individuals have from Neanderthals or Denisovans is certainly interesting. But ancestry proportions provide limited information about the consequences of these ancient matings.</p>
<p>For instance, does DNA inherited from Neanderthals and Denisovans influence biological functions that occur within our cells? Does this DNA influence traits like eye color or susceptibility to disease? Were DNA sequences from our evolutionary cousins ever beneficial, helping humans adapt to new environments?</p>
<p>To answer these questions, we need to identify the bits of Neanderthal and Denisovan DNA scattered throughout the genomes of modern individuals.</p>
<p>In 2014, <a href="https://akeylab.princeton.edu">my group</a> and <a href="https://reich.hms.harvard.edu">David Reich’s group</a> independently published the <a href="https://www.science.org/doi/10.1126/science.1245938">first maps of</a> <a href="https://www.nature.com/articles/nature12961">Neanderthal sequences</a> that survive in the DNA of modern humans. Today, roughly 40% of the Neanderthal genome has been recovered not by sequencing ancient DNA recovered from a fossil, but indirectly by <a href="https://doi.org/10.1016/j.cub.2022.08.027">piecing together the Neanderthal sequences</a> that persist in the genomes of contemporary individuals.</p>
<p>Similarly, in 2016 <a href="https://doi.org/10.1126/science.aad9416">my group</a> and <a href="https://doi.org/10.1016/j.cub.2016.03.037">David Reich’s group</a> published the first comprehensive catalogs of DNA sequences in modern individuals inherited from Denisovan ancestors. Surprisingly, when we analyzed the Denisovan sequences that persist in people today, we discovered they came from two distinct Denisovan populations, and therefore at least <a href="https://doi.org/10.1016/j.cell.2018.02.031">two separate waves of matings occurred between Denisovans and modern humans</a>. </p>
<p>The analysis of Neanderthal and Denisovan DNA in modern humans reveals that some of their sequence was harmful and rapidly got purged from human genomes. In fact, the initial fraction of Neanderthal ancestry in humans who lived approximately 45,000 years ago was around 10%. That amount rapidly declined over a small number of generations to the 2% <a href="https://doi.org/10.1073/pnas.1814338116">observed in contemporary individuals</a>.</p>
<p>The removal of deleterious archaic sequences also created large regions of the human genome that are significantly depleted of both Neanderthal and Denisovan ancestry. These deserts of archaic hominin sequences are interesting because they may help identify genetic changes that contribute to <a href="https://www.ncbi.nlm.nih.gov/books/NBK210023/">uniquely modern human traits</a>, such as our capacity for language, symbolic thought and culture, although there is debate about just <a href="https://doi.org/10.1098/rstb.2019.0424">how unique these traits are to modern humans</a>. </p>
<p>In contrast, there are also sequences inherited from Neanderthals and Denisovans that were advantageous, and helped modern humans adapt to new environments as they dispersed out of Africa. Neanderthal versions of several immune-related genes have risen to high frequency in several non-African populations, which likely <a href="https://www.quantamagazine.org/how-neanderthal-dna-helps-humanity-20160526/">helped humans fend off exposure to new pathogens</a>. Similarly, a version of the <em>EPAS1</em> gene, which contributes to <a href="https://www.nationalgeographic.com/science/article/sex-with-extinct-humans-passed-high-altitude-gene-to-tibetans">high-altitude adaptation</a> in Tibetan populations, was inherited from Denisovans.</p>
<p>It is also becoming clear that DNA sequences inherited from Neanderthal and Denisovan ancestors contribute to the burden of disease in present day individuals. Neanderthal sequences have been shown to <a href="https://doi.org/10.1038/s41586-020-2818-3">influence both susceptibility to</a> and <a href="https://doi.org/10.1073/pnas.2026309118">protection against severe COVID-19</a>. Archaic hominin sequences have also <a href="https://doi.org/10.1016/j.cub.2022.08.027">been shown to influence</a> susceptibility to depression, Type 2 diabetes and celiac disease among others. Ongoing studies will undoubtedly reveal more about how Neanderthal and Denisovan ancestry contributes to human disease.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/488685/original/file-20221007-17489-agxzvz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="photo of man holding a human skull and looking at the face" src="https://images.theconversation.com/files/488685/original/file-20221007-17489-agxzvz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/488685/original/file-20221007-17489-agxzvz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/488685/original/file-20221007-17489-agxzvz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/488685/original/file-20221007-17489-agxzvz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/488685/original/file-20221007-17489-agxzvz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/488685/original/file-20221007-17489-agxzvz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/488685/original/file-20221007-17489-agxzvz.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">Svante Pääbo’s work built the foundation of the new field of paleogenomics.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/svante-paabo-director-of-the-max-planck-institute-for-news-photo/1243699506">Jens Schluete via Getty Images News</a></span>
</figcaption>
</figure>
<p>I was a graduate student when the <a href="https://www.genome.gov/11006929/2003-release-international-consortium-completes-hgp">Human Genome Project</a> was nearing completion a little over two decades ago. I was drawn to genetics because I found it fascinating that, by analyzing the DNA of present-day individuals, you could learn aspects about a population’s history that occurred tens of thousands of years ago.</p>
<p>Today, I am just as fascinated by the stories contained in our DNA, and the work of Svante Pääbo and his colleagues has enabled these stories to be told in a way that simply was not possible before.</p><img src="https://counter.theconversation.com/content/191913/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Joshua Akey receives funding from NIH. </span></em></p>Ancient DNA helps reveal the tangled branches of the human family tree. Not only did our ancestors live alongside other human species, they mated with them, too.Joshua Akey, Professor at the Lewis-Sigler Institute for Integrative Genomics, Princeton UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1902742022-09-21T16:39:22Z2022-09-21T16:39:22ZSix recent discoveries that have changed how we think about human origins<figure><img src="https://images.theconversation.com/files/485592/original/file-20220920-3640-v1n0aj.jpg?ixlib=rb-1.1.0&rect=17%2C34%2C5734%2C3794&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Neanderthal adult male, based on 40,000 year-old remains found at Spy in Belgium.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/london-uk-march-11-2018-neanderthal-1130172149">IR Stone/Shutterstock</a></span></figcaption></figure><p>Scientific study of human evolution historically reassured us of a comforting order to things. It has painted humans as as cleverer, more intellectual and caring than our ancestral predecessors. </p>
<p>From <a href="http://blog.wbkolleg.unibe.ch/wp-content/uploads/Sommer2006_MirrorMirrorNeanderthals.pdf">archaeological reconstructions of Neanderthals</a> as stooped, hairy and brutish, to “cavemen” movies, our ancient ancestors got a bad press. </p>
<p>Over the last five years discoveries have upended this unbalanced view. In my recent book, <a href="https://universitypress.whiterose.ac.uk/site/books/m/10.22599/HiddenDepths/">Hidden Depths: The Origins of Human Connection</a>, I argue that this matters for how we see ourselves today and so how we imagine our futures, as much as for our understanding of our past. </p>
<p>Six revelations stand out.</p>
<p><strong>1. There are more human species than we ever imagined</strong> </p>
<p>Species such as <em><a href="https://en.wikipedia.org/wiki/Homo_longi">Homo Longi</a></em> have only been identified as recently as 2018. There are now <a href="https://www.livescience.com/how-many-human-species.html">21 known species of human</a>. </p>
<p>In the last few years we have realised that our <em>Homo sapiens</em> ancestors may have met as many as eight of these different types of human, from robust and stocky species including Neanderthals and their close relatives Denisovans, to the short (less than 5ft tall) and small-brained humans such as <em><a href="https://www.nhm.ac.uk/discover/homo-naledi-your-most-recently-discovered-human-relative.html">Homo naledi</a></em>. </p>
<p>But <em>Homo sapiens</em> weren’t the inevitable evolutionary destination. Nor do they fit into any simple linear progression or <a href="https://www.sapiens.org/biology/evolution-march-of-progress/">ladder of progress</a>. <em>Homo naledi</em>‘s brain may have been smaller than that of a chimpanzee but there is evidence they were culturally complex and <a href="https://www.youtube.com/watch?v=YLJVHgCZmzI">mourned their dead</a>.</p>
<p>Neanderthals <a href="https://www.nature.com/articles/s41559-021-01506-z">created symbolic art</a> but they weren’t the same as us. Neanderthals had many different <a href="https://www.sapiens.org/biology/neanderthal-anatomy/">biological adaptations</a>, which may <a href="https://www.theguardian.com/science/2020/dec/20/early-humans-may-have-survived-the-harsh-winters-by-hibernating">have included hibernation</a>. </p>
<p><strong>2. Hybrid humans are part of our history</strong></p>
<p>Hybrid species of human, once seen by experts as science fiction, may have played a key role in our evolution. Evidence of the importance of <a href="https://www.nature.com/articles/s41559-022-01875-z">hybrids</a> comes from genetics. The trail is not only in the DNA of our own species (which often includes important genes inherited from Neanderthals) but also skeletons of hybrids. </p>
<p>One example is “<a href="https://www.theguardian.com/science/2018/nov/24/denisovan-neanderthal-hybrid-denny-dna-finder-project">Denny</a>,” a girl with a <a href="https://www.nature.com/articles/d41586-018-06004-0">Neanderthal mother and Denisovan father</a>. Her bones were found in a cave in Siberia. </p>
<p><strong>3. We got lucky</strong></p>
<p>Our <a href="https://www.nature.com/articles/s41559-022-01787-y">evolutionary past</a> is messier than scientists used to think. Have you ever been troubled with backache? Or stared jealously after your dog as it lolloped across an uneven landscape? </p>
<p>That should have been enough to show you we are far from perfectly adapted. We have known for some time that evolution cobbles together solutions in response to an ecosystem which may already have changed. However, many of the changes in our human evolutionary lineage maybe the result of <a href="https://www.sciencedirect.com/science/article/abs/pii/S004724841630152X?via%3Dihub">chance</a>. </p>
<p>For example, where isolated populations have a characteristic, such as some aspect of their appearance, which doesn’t make much difference to their survival and this form continues to change in descendants. Features of Neanderthals’ faces (such as their pronounced brows) or body (including large rib cages) might have resulted simply from genetic drift. </p>
<p><a href="https://onlinelibrary.wiley.com/doi/abs/10.1002/evan.21883">Epigenetics</a>, which is where genes are only activated in specific environments, complicate things too. Genes might predispose someone to depression or schizophrenia for example. Yet they may only develop the condition if triggered by things that happen to them.</p>
<p><strong>4. Our fate is intertwined with nature</strong></p>
<p>We may like to imagine ourselves as masters of the environment. But it is
increasingly clear ecological changes moulded us. </p>
<p>The <a href="https://www.science.org/doi/10.1126/sciadv.abc8975">origins of our own species</a> coincided with major shifts in climate as we became more distinct from other species at these points in time. All other species of human seem to have <a href="https://www.cell.com/one-earth/fulltext/S2590-3322(20)30476-0?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS2590332220304760%3Fshowall%3Dtrue">died out</a> as a result of climate change. </p>
<p>Three major human species <em>Homo erectus, Homo heidelbergensis</em>, and <em>Homo neanderthalensis</em> died out with major shifts in climate such as the Adams event. This was a temporary breakdown of Earth’s magnetic field 42,000 years ago, which coincided with the <a href="https://newsroom.unsw.edu.au/news/science-tech/ancient-relic-points-turning-point-earths-history-42000-years-ago#">extinction of the Neanderthals</a>. </p>
<p><strong>5. Kindness is an evolutionary advantage</strong></p>
<p>Research has uncovered new reasons to feel hopeful about future human societies. Scientists used to believe the <a href="https://www.academia.edu/39331079/EMERGENT_WARFARE_IN_OUR_EVOLUTIONARY_PAST">violent parts of human nature</a> gave us a leg up the evolution ladder. </p>
<p>But evidence has emerged of the <a href="https://universitypress.whiterose.ac.uk/site/chapters/m/10.22599/HiddenDepths.c/">caring side</a> of human nature and its contribution to our success. Ancient skeletons show remarkable signs of survival from illness and injuries, which would have been difficult if not impossible without help. </p>
<p>The trail of human compassion extends back one and a half million years ago. Scientist have traced medical knowledge to at least the time of the Neanderthals. </p>
<p>Altruism has many <a href="https://www.sciencedirect.com/science/article/pii/S0277379118305389">important survival benefits</a>. It enabled older community members to pass on important knowledge. And medical care kept skilled hunters alive. </p>
<p><strong>6. We’re a sensitive species</strong></p>
<p>Evolution made us more emotionally exposed than we like to imagine. Like <a href="https://universitypress.whiterose.ac.uk/site/chapters/m/10.22599/HiddenDepths.h/">domestic dogs</a>, with whom we share many genetic adaptations, such as greater tolerance for outsiders, and sensitivity to social cues, human hypersociability has come with a price: emotional vulnerabilities. </p>
<p>We are more sensitive to how people around us feel, and more vulnerable to social influences, we’re more <a href="https://www.frontiersin.org/articles/10.3389/fpsyg.2020.582090/full">prone to emotional disorders</a>, to <a href="https://pubmed.ncbi.nlm.nih.gov/32561254/">loneliness</a> and to <a href="https://www.scientificamerican.com/article/depressions-evolutionary/">depression</a> than our predecessors. Our complex feelings may not always be pleasant to live with, but they are part of <a href="https://link.springer.com/article/10.1007/s10816-020-09503-5">key transformations</a> which created large, connected communities. Our emotions are essential to human collaborations. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/485641/original/file-20220920-9768-9z7s5f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/485641/original/file-20220920-9768-9z7s5f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=412&fit=crop&dpr=1 600w, https://images.theconversation.com/files/485641/original/file-20220920-9768-9z7s5f.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=412&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/485641/original/file-20220920-9768-9z7s5f.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=412&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/485641/original/file-20220920-9768-9z7s5f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=517&fit=crop&dpr=1 754w, https://images.theconversation.com/files/485641/original/file-20220920-9768-9z7s5f.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=517&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/485641/original/file-20220920-9768-9z7s5f.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=517&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A socialised wolf enjoying affectionate contact.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:He_can_stand_stroking,_too..._(27205424372).jpg">Vilmos Vincze / Wikimedia Commons:</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>This is a far less reassuring view of our place in the world than the one we had even five years ago. But seeing ourselves as selfish, rational and entitled to a privileged place in nature hasn’t worked out well. Just read the latest reports about the state of our planet.</p>
<p>If we accept that humans are not a pinnacle of progress, then we cannot just wait for things to turn out right. Our past suggests that our future won’t get better unless we do something about it.</p><img src="https://counter.theconversation.com/content/190274/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Penny Spikins received funding from The John Templeton Foundation, grant 59475, for the production of Hidden Depths: the origins of human connection (White Rose University Press). </span></em></p>You may have heard science has reconsidered its view of Neanderthals but did you know human hybrid species played a key role in our evolution?Penny Spikins, Professor of the Archaeology of Human Origins, University of YorkLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1859042022-07-25T04:02:29Z2022-07-25T04:02:29ZIrony machine: why are AI researchers teaching computers to recognise irony?<figure><img src="https://images.theconversation.com/files/473359/original/file-20220711-19-5d335n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">shutterstock thinking robot</span> </figcaption></figure><p>What was your first reaction when you heard about <a href="https://theconversation.com/a-google-software-engineer-believes-an-ai-has-become-sentient-if-hes-right-how-would-we-know-185024">Blake Lemoine</a>, the Google engineer who announced last month the AI program he was working on had developed consciousness?</p>
<p>If, like me, you’re instinctively suspicious, it might have been something like: <em>Is this guy serious? Does he honestly believe what he is saying? Or is this an elaborate hoax?</em></p>
<p>Put the answers to those questions to one side. Focus instead on the questions themselves. Is it not true that even to <em>ask</em> them is to presuppose something crucial about Blake Lemoine: specifically, <em>he</em> is conscious?</p>
<p>In other words, we can all imagine Blake Lemoine being deceptive.</p>
<p>And we can do so because we assume there is a difference between his inward convictions – what he genuinely believes – and his outward expressions: what he <em>claims</em> to believe.</p>
<p>Isn’t that difference the mark of consciousness? Would we ever assume the same about a computer?</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/a-google-software-engineer-believes-an-ai-has-become-sentient-if-hes-right-how-would-we-know-185024">A Google software engineer believes an AI has become sentient. If he’s right, how would we know?</a>
</strong>
</em>
</p>
<hr>
<h2>Consciousness: ‘the hard problem’</h2>
<p>It is not for nothing philosophers have taken to calling consciousness “<a href="https://iep.utm.edu/hard-problem-of-conciousness/#:%7E:text=The%20hard%20problem%20of%20consciousness%20is%20the%20problem%20of%20explaining,directly%20appear%20to%20the%20subject.">the hard problem</a>”. It is notoriously difficult to define.</p>
<p>But for the moment, let’s say a conscious being is one capable of having a thought and not divulging it.</p>
<p>This means consciousness would be the prerequisite for irony, or saying one thing while meaning the opposite. I know you are being ironic when I realise your words <em>don’t</em> correspond with your thoughts.</p>
<p>That most of us have this capacity – and most of us routinely convey our unspoken meanings in this manner – is something that, I think, should surprise us more often than it does.</p>
<p>It seems almost discretely human.</p>
<p>Animals can certainly be funny – but not deliberately so. </p>
<p>What about machines? Can they deceive? Can they keep secrets? Can they be ironic?</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/475553/original/file-20220722-24-8kdn4w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="a kitten peeks out from between a pile of knits" src="https://images.theconversation.com/files/475553/original/file-20220722-24-8kdn4w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/475553/original/file-20220722-24-8kdn4w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/475553/original/file-20220722-24-8kdn4w.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/475553/original/file-20220722-24-8kdn4w.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/475553/original/file-20220722-24-8kdn4w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/475553/original/file-20220722-24-8kdn4w.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/475553/original/file-20220722-24-8kdn4w.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">Animals can be funny, but not on purpose.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>AI and irony</h2>
<p>It is a truth universally acknowledged (among academics at least) that any research question you might cook up with the letters “AI” in it is already being studied somewhere by an army of obscenely well-resourced computational scientists – often, if not always, funded by the US military.</p>
<p>This is certainly the case with the question of AI and irony, which has recently attracted a significant amount of <a href="https://www.frontiersin.org/articles/10.3389/fnhum.2021.791374/full">research interest</a>.</p>
<p>Of course, given that irony involves saying one thing while meaning the opposite, creating a machine that can detect it, let alone generate it, is no simple task.</p>
<p>But if we <em>could</em> create such a machine, it would have a multitude of practical applications, some more sinister than others.</p>
<p>In the age of online reviews, for example, retailers have become very keen on <a href="https://www.mdpi.com/1099-4300/23/4/394">so-called</a> “opinion mining” and “sentiment analysis”, which uses AI to map not merely the content, but the mood of reviewer’s comments. </p>
<p>Knowing whether your product is being praised or becoming the butt of the joke is valuable information.</p>
<p>Or consider content moderation on social media. If we want to limit online abuse while protecting freedom of speech, would it not be helpful to know when someone is serious and when they are joking?</p>
<p>Or what if someone tweets that they have just joined their local terrorist cell or they’re packing a bomb in their suitcase and heading for the airport? (Don’t ever tweet that, by the way.) Imagine if we could determine instantly whether they are serious, or whether they are just “being ironic”. </p>
<p>In fact, given irony’s proximity to lying, it’s not hard to imagine how the entire shadowy machinery of governmental and corporate surveillance that has grown up around new communications technologies would find the prospect of an irony-detector extremely interesting. </p>
<p>And that goes a long way towards explaining the growing literature on the topic.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/weaponised-irony-after-fictionalising-elizabeth-macarthurs-life-kate-grenville-edits-her-letters-180335">'Weaponised irony': after fictionalising Elizabeth Macarthur's life, Kate Grenville edits her letters</a>
</strong>
</em>
</p>
<hr>
<h2>AI, from Clippy to facial recognition</h2>
<p>To understand the state of current research into AI and irony, it is helpful to know a little about <a href="https://books.google.com.au/books/about/Your_Wit_Is_My_Command.html?id=toY8EAAAQBAJ&printsec=frontcover&source=kp_read_button&hl=en&newbks=1&newbks_redir=0&redir_esc=y#v=onepage&q&f=false">the history of AI</a> more generally. </p>
<p>That history is typically broken down into two periods.</p>
<p>Until the 1990s, researchers sought to program computers with a set of handcrafted formal rules for how to behave in predefined situations. </p>
<p>If you used Microsoft Word in the 1990s, you might remember the irritating office assistant Clippy, who was endlessly popping up to offer unwanted advice.</p>
<p>Since the turn of the century, that model has been replaced by data-driven machine learning and neural networks.</p>
<p>Here, enormous caches of examples of a given phenomena are translated into numerical values, on which computers can perform complex mathematical operations to determine patterns no human could ever discover.</p>
<p>Moreover, the computer does not merely apply a rule. Rather, it learns from experience, and develops new operations independent of human intervention.</p>
<p>The difference between the two approaches is the difference between Clippy and, say, facial recognition technology.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/facial-recognition-is-on-the-rise-but-the-law-is-lagging-a-long-way-behind-185510">Facial recognition is on the rise – but the law is lagging a long way behind</a>
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</em>
</p>
<hr>
<h2>Researching sarcasm</h2>
<p>To build <a href="https://aclanthology.org/W16-0425/">a neural network with the ability to detect irony</a>, researchers focus initially on what some would consider its simplest form: sarcasm.</p>
<p>The researchers begin with data stripped from social media.</p>
<p>For instance, they might collect all tweets labelled #sarcasm or Reddit posts labelled /s, a shorthand that Reddit users employ to indicate they are not serious.</p>
<p>The point is not to teach the computer to recognise the two separate meanings of any given sarcastic post. Indeed, meaning is of no relevance whatsoever.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1549009741602504706"}"></div></p>
<p>Instead, the computer is instructed to search for recurring patterns, or what one researcher calls “syntactical fingerprints” – words, phrases, emojis, punctuation, errors, contexts, and so forth.</p>
<p>On top of that, the data set is bolstered by adding more streams of examples – other posts in the same threads, for instance, or from the same account.</p>
<p>Each new individual example is then run through a battery of calculations until we arrive at a single determination: sarcastic or not sarcastic.</p>
<p>Finally, a bot can be programmed to reply to each original poster and ask whether they were being sarcastic. Any response can be added to the computer’s growing mountain of experience.</p>
<p>The success rate of the most recent sarcasm detectors approaches <a href="https://aclanthology.org/W16-0425/">an astonishing 90%</a> – greater, I suspect, than many humans could achieve. </p>
<p>So, assuming AI will continue to advance at the rate that took us from Clippy to facial recognition technology in less than two decades, can ironic androids be far off?</p>
<h2>What is irony?</h2>
<p>But isn’t there a qualitative difference between sorting through the “syntactical fingerprints” of irony and actually understanding it?</p>
<p>Some would suggest <a href="https://en.wikipedia.org/wiki/Synthetic_intelligence">not</a>. If a computer can be taught to behave exactly like a human, then it’s immaterial whether a rich internal world of meaning lurks beneath its behaviour.</p>
<p>But irony is arguably a unique case: it <em>relies</em> on the distinction between external behaviours and internal beliefs.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/7GM--22zOlw?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">In 1994 film Reality Bites, Ethan Hawke’s character famously defines irony (in very simplistic terms).</span></figcaption>
</figure>
<p>Here it might be worth remembering that, while computational scientists have only recently become interested in irony, philosophers and literary critics have been thinking about it for a very long time.</p>
<p>And perhaps exploring that tradition would shed old light, as it were, on a new problem.</p>
<p>Of the many names one could invoke in this context, two are indispensable: the German Romantic philosopher <a href="https://plato.stanford.edu/entries/schlegel/">Friedrich Schlegel</a>; and the post-structuralist literary theorist <a href="https://www.oxfordbibliographies.com/view/document/obo-9780190221911/obo-9780190221911-0023.xml">Paul de Man</a>.</p>
<p>For Schlegel, irony does not simply entail a false, external meaning and a true, internal one. Rather, in irony, two opposite meanings are presented as equally true. And the resulting indeterminacy has devastating implications for logic, most notably the law of non-contradiction, which holds that a statement cannot be simultaneously true and false.</p>
<p>De Man follows Schlegel on this score, and in a sense, universalises his insight. He <a href="http://users.clas.ufl.edu/burt/unintelgbledethbyflm/concepofirony.pdf">notes</a> every effort to define a concept of irony is bound to be infected by the phenomena it purports to explain. </p>
<p>Indeed, de Man believes <em>all</em> language is infected by irony, and involves what he calls “permanent parabasis”. Because humans have the power to conceal their thoughts from one another, it will always be possible – permanently possible – that they do not mean what they are saying. </p>
<p>Irony, in other words, is not one kind of language among many. It structures – or better, haunts – every use of language and every interaction.</p>
<p>And in this sense, it exceeds the order of proof and computation. The question is whether the same is true of human beings in general.</p><img src="https://counter.theconversation.com/content/185904/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Charles Barbour 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>Irony is linked to the ability to say one thing while thinking another – which means it’s also intrinsic to being human. What does new research into artificial intelligence and irony reveal?Charles Barbour, Senior Lecturer, School of Humanities and Communication Arts, Western Sydney UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1791502022-03-21T20:33:21Z2022-03-21T20:33:21ZUkraine refugee crisis exposes racism and contradictions in the definition of human<figure><img src="https://images.theconversation.com/files/452270/original/file-20220315-25-i4kwhh.jpg?ixlib=rb-1.1.0&rect=242%2C335%2C7467%2C4774&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">African residents in Ukraine wait at Lviv railway station on Feb. 27, 2022. The Ukraine refugee crisis revealed deep-seated racism as racialized and Black refugees from Ukraine were treated differently.</span> <span class="attribution"><span class="source">(AP Photo/Bernat Armangue)</span></span></figcaption></figure><p>Not only has the Russian invasion of Ukraine brought to light the awful tragedies that accompany armed conflict, but the subsequent refugee crisis has also uncovered deeply seated racism in the country. </p>
<p>Reporters have documented dehumanizing treatment against <a href="https://nypost.com/2022/03/05/russia-ukraine-war-african-students-say-they-faced-guns-hostile-guards-as-they-fled-ukraine/?utm_source=twitter_sitebuttons&utm_medium=site%20buttons&utm_campaign=site%20buttons">international students from Africa</a>, <a href="https://www.abc.net.au/news/2022-03-16/indian-students-trapped-in-ukraine-amid-accusations-of-racism/100910370">South Asia</a> and <a href="https://www.aljazeera.com/news/2022/3/5/thats-poland-now-walk-arab-students-plight-out-of-ukraine">the Middle East</a> in Ukraine. This treatment also extended to racialized permanent residents of Ukraine, <a href="https://www.cbc.ca/radio/day6/fleeing-ukraine-twisted-sister-s-dee-snider-batman-movies-ranked-pandemic-travel-tips-and-more-1.6373164/nigerian-doctor-fleeing-kyiv-for-poland-calls-treatment-by-ukrainian-officials-dehumanizing-1.6373301">including a long-time practising Nigerian doctor</a>.</p>
<p>While white women and children were given priority on vehicles departing the country, <a href="https://www.cbc.ca/listen/live-radio/1-63-the-current/clip/15898360-russians-speaking-invasion-ukraine-despite-risk-entails-refugees?share=true">African women</a> were barred from trains leaving Kyiv even though there were empty seats.</p>
<p>These incidents demonstrate a racist logic that positions some people as vulnerable, and others as beyond the realm of moral obligation to receive protection. Black and racialized people, it seems, are not as deserving of care. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1497974245737050120"}"></div></p>
<p>As Black Studies researchers in the field of education, we study how colonialism and anti-Blackness shape what we know. Although some have been shocked by these reports, we are not surprised. </p>
<p>The contradictions inherent in the incidents of racism occurring in Ukraine are part of a long legacy of the exclusive ways the West defines who counts as human.</p>
<h2>Appalled, but not surprised</h2>
<figure class="align-center ">
<img alt="A group of Black students wait at a railway station with suitcases." src="https://images.theconversation.com/files/452574/original/file-20220316-8547-1x1mdi4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/452574/original/file-20220316-8547-1x1mdi4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/452574/original/file-20220316-8547-1x1mdi4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/452574/original/file-20220316-8547-1x1mdi4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/452574/original/file-20220316-8547-1x1mdi4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/452574/original/file-20220316-8547-1x1mdi4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/452574/original/file-20220316-8547-1x1mdi4.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">Nigerian students trying to flee Ukraine wait at the platform in Lviv railway station in February.</span>
<span class="attribution"><span class="source">(AP Photo/Bernat Armangue, File)</span></span>
</figcaption>
</figure>
<p>The liberal notion of western society was forged during the 15th-19th centuries <a href="https://cosmopolis.woo.cat/media/pages/events/08-11-19/collective-thinking/2931087183-1573123705/sylvia-wynter-1492-a-new-world-view.pdf">when Africans were enslaved across the West</a>. Because of this, liberal conceptions of justice do not consider Indigenous, Black and racialized persons to be on the same level as white Europeans. </p>
<p>For example, the French Revolution pursued the values of liberté, egalité, fraternité even <a href="https://www.penguinrandomhouse.com/books/86417/the-black-jacobins-by-c-l-r-james/">while the French fought to uphold Black enslavement in Haiti (then known as Saint Domingue).</a> </p>
<p>Similarly, the American constitution declared that “all men are created equal” while declaring that <a href="https://www.blackpast.org/african-american-history/events-african-american-history/three-fifths-clause-united-states-constitution-1787/">Black persons counted as only three-fifths of a person</a>.</p>
<p><a href="https://doi.org/10.4000/rccs.6793">The 1948 UN Declaration of human rights</a> was created to contest Nazism and anti-semitism, but did not seek to redress centuries of colonialism of racialized people. Author and poet <a href="https://www.jstor.org/stable/j.ctt9qfkrm.4">Aimé Césaire pointed out</a>: “Europeans tolerated Nazism before it was inflicted on them… because until then, it had been applied only to non-European people.”</p>
<h2>Different levels of ‘human’</h2>
<p>Jamaican philosopher Sylvia Wynter explores the contradictions within our working definitions of what it means to be human. She explains that since <a href="https://trueleappress.files.wordpress.com/2020/04/wynter-columbus-and-the-poetics-of-the-propter-nos-1.pdf">the rise of Renaissance Humanism</a> and the spread of colonialism, western origin stories have used a binary opposition between an ideal <a href="https://doi.org/10.1353/ncr.2004.0015">Human and a “dysselected other”</a>, where the “other” is Black, Indigenous or racialized. </p>
<p>Beginning in the 15th century, when Europeans began colonizing the Americas, <a href="https://monoskop.org/File:Wynter_Sylvia_1995_The_Pope_Must_Have_Been_Drunk_the_King_of_Castile_a_Madman.pdf">European intellectuals introduced an origin story</a> that considered rationality the defining characteristic of being human. </p>
<p>In contrast, they <a href="https://www.dloc.com/UF00090030/00043/images/26">framed Indigenous people in the Americas, and Africans everywhere, as inherently lacking rationality</a>, marking them as less than fully human. This logic justified European colonialism and the dispossession of Indigenous peoples. Africans and their descendants would be viewed as enslaveable by nature, supposedly the most lacking in reason. </p>
<p>Around the 18th century, <a href="https://doi.org/10.1353/ncr.2004.0015">a revised origin story</a> placed all human groups in a supposed evolutionary hierarchy in which white people were seen as the pinnacle of human development. </p>
<p>All these origin stories have one thing in common: they require the dehumanization of non-white, and especially Black, people. The idea of Black humanity becomes an oxymoron. </p>
<p>As the crisis in Ukraine shows, this continues today, allowing some human beings to be disregarded as what <a href="https://www.editionsladecouverte.fr/les_damnes_de_la_terre-9782707142818">Frantz Fanon calls “les damnés.”</a> The racist behaviour at both individual and state levels is rooted in longstanding origin stories. </p>
<figure class="align-center ">
<img alt="A soldier holds a bundled up baby while another soldier stands beside him with a bag" src="https://images.theconversation.com/files/452570/original/file-20220316-7542-1n88184.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/452570/original/file-20220316-7542-1n88184.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/452570/original/file-20220316-7542-1n88184.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/452570/original/file-20220316-7542-1n88184.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/452570/original/file-20220316-7542-1n88184.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/452570/original/file-20220316-7542-1n88184.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/452570/original/file-20220316-7542-1n88184.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">Polish soldiers come to the aid of refugees fleeing war in neighboring Ukraine as they arrive at the Medyka border crossing on March 10, 2022.</span>
<span class="attribution"><span class="source">(AP Photo/Daniel Cole)</span></span>
</figcaption>
</figure>
<h2>The boundary between ‘humans’ and others</h2>
<p>The prioritization of some people over others, based on racist logic, is a result of these origin stories. </p>
<p>Some reporters have expressed disbelief that a refugee crisis could occur in Europe among people <a href="https://www.washingtonpost.com/media/2022/02/27/media-ukraine-offensive-comparisons/">“so like us.”</a> </p>
<p><a href="https://www.minnpost.com/community-voices/2022/03/why-dont-we-treat-all-refugees-as-though-they-were-ukrainian/">White Ukrainian refugees are treated differently than racialized refugees</a> from places like <a href="https://www.washingtonpost.com/world/2022/03/17/calais-ukraine-refugees-migrants/">South Sudan</a>, Somalia, Syria, Afghanistan and Haiti.</p>
<p>For example, Canada has accepted <a href="https://www.cbc.ca/news/politics/multiple-refugee-crises-across-globe-put-pressure-on-canada-s-immigration-system-1.6389238">the same number of refugees from Ukraine in the last three months as from Afghanistan</a> over the past year, despite longstanding promises to accept Afghan refugees.</p>
<p>European countries that <a href="https://www.politico.eu/article/politics-nationalism-and-religion-explain-why-poland-doesnt-want-refugees/">originally resisted admitting racialized refugees have now felt moved to provide refuge</a> for their fellow white Europeans. </p>
<p>The imagined racial boundary between selected and dysselected explains this difference in treatment. This boundary is so entrenched, that even when racism is pointed out, it is difficult for many to avoid. </p>
<p>When asked about the reports of racism, <a href="https://www.independent.co.uk/news/world/europe/ukraine-ambassador-black-asian-refugees-racism-b2031847.html">Ukraine ambassador to the United Kingdom Vadym Prystaiko said</a>: </p>
<blockquote>
<p>“Maybe we will put all foreigners in some other place so they won’t be visible… And (then) there won’t be conflict with Ukrainians trying to flee in the same direction.” </p>
</blockquote>
<h2>A vision of ‘the human’ for all humans</h2>
<p>Genuine change begins with a re-imagined notion of the human. <a href="https://trueleappress.files.wordpress.com/2020/04/wynter.black-studies-manifesto.pdf">Wynter advocates for</a> the rupture of these definitions of the “human” and replacing them with a revolutionary definition that values all humans. </p>
<p>Wynter also says that a revolutionary notion of the human is best crafted by those who most experience <a href="https://www.taylorfrancis.com/chapters/mono/10.4324/9781315052717-8/towards-sociogenic-principle-fanon-identity-puzzle-conscious-experience-like-black-antonio-gomez-moriana-mercedes-duran-cogan">the discrepancy between the current definition of the “human” and their own humanity</a>. </p>
<p>Indeed, throughout history, Black freedom movements have been essential to challenging dehumanizing conditions. They have recognized the futility of depending on western systems to correct themselves since they are founded on anti-Blackness. </p>
<p>In this spirit, we pose these questions for consideration:</p>
<ul>
<li><p>What does it mean to be human, and what will it take for us to recognize everyone’s humanity, vulnerability and dignity without condition?</p></li>
<li><p>What might be required to make ostensible spaces of refuge into true refuge for everyone? </p></li>
<li><p>How might the experiences of Black and racialized persons in this crisis be embraced as the foundation for necessary policy change?</p></li>
<li><p>What can we learn from Black Studies and Black liberation struggles toward crafting a vision of the “human” in which all humans count?</p></li>
</ul><img src="https://counter.theconversation.com/content/179150/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>The racism seen in the Ukraine refugee crisis reflects a long legacy of how the West defines who is human. We need a new definition that respects the dignity of all humans.Philip S. S. Howard, Assistant Professor of Education, McGill UniversityBryan Chan Yen Johnson, Faculty Lecturer, School of Continuing Studies, McGill UniversityKevin Ah-Sen, PhD Student in Education, McGill UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1219322020-01-14T13:48:42Z2020-01-14T13:48:42ZBeing copycats might be key to being human<figure><img src="https://images.theconversation.com/files/309363/original/file-20200109-80144-17dxqav.jpg?ixlib=rb-1.1.0&rect=0%2C131%2C3736%2C2687&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Imitation is the sincerest form of being human?</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/father-teaching-son-how-tie-like-747377575">Rawpixel.com/Shutterstock.com</a></span></figcaption></figure><p>Chimpanzees, human beings’ closest animal relatives, <a href="https://www.nationalgeographic.com/news/2005/8/chimps-humans-96-percent-the-same-gene-study-finds/">share up to 98% of our genes</a>. Their human-like hands and facial expressions can send uncanny shivers of self-recognition down the backs of zoo patrons.</p>
<p>Yet people and chimpanzees lead very different lives. <a href="https://www.iucnredlist.org/species/15933/129038584%23population">Fewer than 300,000 wild chimpanzees</a> live in a few forested corners of Africa today, while humans have colonized every corner of the globe, from the Arctic tundra to the Kalahari Desert. At <a href="https://theconversation.com/7-5-billion-and-counting-how-many-humans-can-the-earth-support-98797">more than 7 billion</a>, humans’ population dwarfs that of nearly all other mammals – despite our physical weaknesses.</p>
<p>What could account for our species’ incredible evolutionary successes? </p>
<p>One obvious answer is <a href="https://theconversation.com/your-big-brain-makes-you-human-count-your-neurons-when-you-count-your-blessings-127398">our big brains</a>. It could be that our raw intelligence gave us an unprecedented ability to think outside the box, innovating solutions to gnarly problems as people migrated across the globe. Think of “<a href="https://www.imdb.com/title/tt3659388/?ref_=fn_al_tt_1">The Martian</a>,” where Matt Damon, trapped alone in a research station on Mars, heroically “<a href="https://www.youtube.com/watch?v=BABM3EUo990">sciences</a>” his way out of certain death.</p>
<p>But a growing number of cognitive scientists and anthropologists are rejecting that explanation. These researchers think that, rather than making our living as innovators, human beings survive and thrive precisely because we don’t think for ourselves. Instead, people cope with challenging climates and ecological contexts by <a href="https://doi.org/10.1016/j.tics.2015.08.005">carefully copying others</a> – especially those we respect. Instead of <em>Homo sapiens</em>, or “man the knower,” we’re really <em><a href="https://doi.org/10.1016/j.infbeh.2003.06.004">Homo imitans</a></em>: “man the imitator.”</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/JwwclyVYTkk?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Chimps and children watch how to open a puzzle box.</span></figcaption>
</figure>
<h2>Watching and learning</h2>
<p>In <a href="https://doi.org/10.1007/s10071-004-0239-6">a famous study</a>, psychologists Victoria Horner and Andrew Whiten showed two groups of test subjects – children and chimpanzees – a mechanical box with a treat inside. In one condition, the box was opaque, while in the other it was transparent. The experimenters demonstrated how to open the box to retrieve a treat, but they also included the irrelevant step of tapping on the box with a stick.</p>
<p>Oddly, human children carefully copied all the steps to open the box, even when they could see that the stick had no practical effect. That is, they copied irrationally: Instead of doing only what was necessary to get their reward, children slavishly imitated every action they’d witnessed.</p>
<p>Of course, that study only included three- and four-year-olds. But additional research has showed that <a href="https://doi.org/10.1098/rstb.2009.0069">older children and adults</a> are <a href="https://doi.org/10.1348/000712610X493115">even more likely</a> to mindlessly copy others’ actions, and <a href="https://doi.org/10.1177/1745691618794921">young infants are less likely</a> to over-imitate – that is, to precisely copy even impractical actions.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/309364/original/file-20200109-80159-s32mwr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/309364/original/file-20200109-80159-s32mwr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/309364/original/file-20200109-80159-s32mwr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=736&fit=crop&dpr=1 600w, https://images.theconversation.com/files/309364/original/file-20200109-80159-s32mwr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=736&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/309364/original/file-20200109-80159-s32mwr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=736&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/309364/original/file-20200109-80159-s32mwr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=925&fit=crop&dpr=1 754w, https://images.theconversation.com/files/309364/original/file-20200109-80159-s32mwr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=925&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/309364/original/file-20200109-80159-s32mwr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=925&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Chimpanzees skip extraneous steps and just do what works, as when using a stick to extract termites to eat.</span>
<span class="attribution"><span class="source">Auscape/Universal Images Group via Getty Images</span></span>
</figcaption>
</figure>
<p>By contrast, chimpanzees in Horner and Whiten’s study only over-imitated in the opaque condition. In the transparent condition – where they saw that the stick was mechanically useless – they ignored that step entirely, merely opening the box with their hands. Other research has since <a href="https://doi.org/10.4000/primatologie.254">supported these findings</a>.</p>
<p>When it comes to copying, chimpanzees are more rational than human children or adults.</p>
<h2>The benefits of following without question</h2>
<p>Where does the seemingly irrational human preference for over-imitation come from? In his book “<a href="https://press.princeton.edu/books/paperback/9780691178431/the-secret-of-our-success">The Secret of Our Success</a>,” anthropologist Joseph Henrich points out that people around the world rely on technologies that are often <a href="https://slatestarcodex.com/2019/06/04/book-review-the-secret-of-our-success/">so complex that no one can learn them rationally</a>. Instead, people must learn them step by step, trusting in the wisdom of more experienced elders and peers.</p>
<p>For example, the best way to master making a bow is by observing successful hunters doing it, with the assumption that everything they do is important. As an inexperienced learner, you can’t yet judge which steps are actually relevant. So when your band’s best hunter waxes his bowstring with two fingers or touches his ear before drawing the string, you copy him. </p>
<p>The human propensity for over-imitation thus makes possible what anthropologists call <a href="https://doi.org/10.1111/bjdp.12139">cumulative culture</a>: the long-term development of skills and technologies over generations. No single person might understand all the practical reasons behind each step to making a bow or carving a canoe, much less transforming rare earth minerals into iPhones. But as long as people copy with high fidelity, the technology gets transmitted.</p>
<p>Ritual and religion are also domains in which people carry out actions that <a href="https://doi.org/10.1016/j.cognition.2015.08.002">aren’t connected in a tangible way with practical outcomes</a>. For example, a Catholic priest blesses wafers and wine for Communion by uttering a series of repetitive words and doing odd motions with his hands. One could be forgiven for wondering what on Earth these ritualistic acts have to do with eating bread, just as a chimpanzee can’t see any connection between tapping a stick and opening a box. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/309365/original/file-20200109-80153-glrsaq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/309365/original/file-20200109-80153-glrsaq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/309365/original/file-20200109-80153-glrsaq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=425&fit=crop&dpr=1 600w, https://images.theconversation.com/files/309365/original/file-20200109-80153-glrsaq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=425&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/309365/original/file-20200109-80153-glrsaq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=425&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/309365/original/file-20200109-80153-glrsaq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=535&fit=crop&dpr=1 754w, https://images.theconversation.com/files/309365/original/file-20200109-80153-glrsaq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=535&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/309365/original/file-20200109-80153-glrsaq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=535&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Rituals bond groups together.</span>
<span class="attribution"><a class="source" href="http://www.apimages.com/metadata/Index/Watchf-Associated-Press-Domestic-News-New-York-/e7637a8aa426406eb02395701dbafee8/2/0">AP Photo</a></span>
</figcaption>
</figure>
<p>But rituals have a hidden effect: They bond people to one another and <a href="https://doi.org/10.1016/j.evolhumbehav.2015.08.002">demonstrate cultural affiliation</a>. For an enlightening negative example, consider a student who refuses to stand for the Pledge of Allegiance. Her action clearly telegraphs her rejection of authorities’ right to tell her how to behave. And as anthropologist Roy Rappaport <a href="https://www.cambridge.org/us/academic/subjects/anthropology/social-and-cultural-anthropology/ritual-and-religion-making-humanity?format=PB">pointed out</a>, ritual participation is binary: Either you say the pledge or you don’t. This clarity makes it easily apparent who is or isn’t committed to the group.</p>
<h2>Surprise secret ingredient that makes us human</h2>
<p>In a broader sense, then, over-imitation helps enable much of what comprises <a href="https://doi.org/10.1111/cdep.12297">distinctively human culture</a>, which turns out to be much more complicated than mechanical cause and effect.</p>
<p>At heart, human beings are not brave, self-reliant innovators, but careful if savvy conformists. We perform and imitate apparently impractical actions because doing so is the key to learning complex cultural skills, and because rituals create and <a href="https://doi.org/10.1111/cdep.12297">sustain the cultural identities and solidarity</a> we <a href="https://doi.org/10.1177/0956797615607205">depend on for survival</a>. Indeed, copying others is a powerful way to <a href="https://doi.org/10.1037/0022-3514.76.6.893">establish social rapport</a>. For example, mimicking another’s body language can induce them to like and trust you more.</p>
<p>So the next time you hear someone arguing passionately that everyone should embrace nonconformity and avoid imitating others, you might chuckle a bit. We’re not chimpanzees, after all.</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?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=youresmart">You can read us daily by subscribing to our newsletter</a>. ]</p><img src="https://counter.theconversation.com/content/121932/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Connor Wood receives funding from the John Templeton Foundation. </span></em></p>A quirk of psychology that affects the way people learn from others may have helped unlock the complicated technologies and rituals that human culture hinges on.Connor Wood, Visiting Researcher in Theology, Boston UniversityLicensed as Creative Commons – attribution, no derivatives.