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    An incredible Denisovan skull is upending the story of human evolution

    DNA evidence indicates that a skull unearthed in Harbin, China, belonged to a DenisovanHebei GEO University
    One of the biggest mysteries in human evolution has just been solved. In 2010, a groundbreaking genetic analysis revealed that east Asia was once home to a previously unknown group of enigmatic ancient humans. We knew them as the Denisovans, but until very recently, we had no idea what they looked like.
    That has now changed thanks to a 146,000-year-old skull unearthed in Harbin, China, in mysterious circumstances more than 90 years ago. In June, we learned that it carries Denisovan DNA in the ancient gunk attached to the surface of a tooth, suggesting that the cranium belonged to this ancient relative of modern humans. The discovery shows that these hominins had an unusual combination of features: their faces were similar to ours, but they had thick brow ridges and lacked our tall foreheads.

    This finding closes one chapter of the Denisovan story. But another has just begun – and it looks set to bring even bigger revelations. For one thing, we can expect a new name for this extinct hominin, with at least two rival proposals for what it should be. There will also be a battle over how to accommodate the Denisovans in our family tree, particularly given the suggestion that they are more closely related to living people than any other ancient human – potentially ousting the Neanderthals from their position as our sister species.
    That controversial idea has big implications in the ongoing search for Ancestor X, the population that gave rise to modern humans. It will also prompt a scramble to learn more about Denisovan lives and behaviour – because it is only by studying our closest cousins that we can really understand how we differ from the other humans that once walked the planet.
    The story of the Denisovans, in terms of our recognition of them, begins just a decade and a half ago. They have been a puzzle since their unconventional discovery in 2010. Unlike other ancient humans, all of which are defined by the physical features of their skeletons, these hominins were originally defined solely on the basis of unusual DNA signatures in a tooth and tiny finger bone – both now thought to be between 51,000 and 84,000 years old – found in Denisova cave in Siberia, Russia. That DNA turned out to come from a human lineage that was related to, but distinct from, the Neanderthals.
    Interbreeding
    Bence Viola at the University of Toronto, Canada, who was a member of the team that made the discovery, says the researchers considered placing the fossils in a new species: Homo altaiensis. They ultimately decided not to, in part because the DNA showed that ancestors of living humans had interbred with the mysterious lineage. We now know that there were several episodes of this interbreeding, and that some human populations – particularly in the islands of South-East Asia and Oceania – inherited between 4 and 6 per cent of their DNA from Denisovans.
    “Species names are problematic when you’re looking at populations that are so closely related,” he says. The team opted instead to give the lineage an informal name – the Denisovans – which some researchers view as merely a population within our species, Homo sapiens.
    There isn’t universal agreement that this was the correct decision, however. Species can be defined in dozens of ways, many of which allow for a limited degree of interbreeding with other species. This means, for instance, that many researchers argue that Neanderthals deserve to be considered as a distinct species – Homo neanderthalensis – despite evidence that they interbred with modern humans. In a study published last year, Andra Meneganzin at KU Leuven, Belgium, and Chris Stringer at the Natural History Museum, London, advocated for this position because the Neanderthals developed a unique set of physical features and exploited resources in a distinct way.
    With such ideas in mind, Christopher Bae at the University of Hawaiʻi at Mānoa recalls being intrigued by the fact that the original Denisovan tooth and a handful of others from Denisova cave were strikingly large. They strongly reminded him of teeth associated with ancient human remains that had been unearthed in China during the 20th century. “I said that it was only a matter of time before the Denisovans were given a Chinese species name,” he says.
    The trouble was, says Bae, that no existing names were available there. Researchers in China had traditionally opted for a simple, linear picture of human evolution and so chose to label any human fossils from the past 200,000 years as either H. sapiens or – if the fossil had a primitive appearance – archaic H. sapiens.

    Today, most researchers in China think our evolutionary tree is more complicated. As such, when Xijun Ni at the Chinese Academy of Sciences in Beijing and his colleagues examined the Harbin skull and concluded it didn’t belong to a Neanderthal or a modern human, they were comfortable with placing it in a new species. In 2021, they named this species Homo longi, derived from a Chinese term meaning “dragon”.
    A few years later, in 2023, Bae attended a scientific meeting in Novi Sad, Serbia, to discuss the human evolutionary tree. “We basically agreed that H. longi is OK,” he says.
    Denisovan DNA discovery
    So, with news earlier this year that the Harbin skull contains Denisovan proteins and there is Denisovan mitochondrial DNA in the tartar adhering to its single tooth, a strong case can be made for saying the Denisovans and H. longi are one and the same. But Bae doesn’t see it that way.
    For a few years, he has suspected that H. longi wasn’t the only ancient human wandering around east Asia in the Stone Age. In particular, he points to fragments of hominin skulls from Xujiayao and Xuchang in north China that are between 100,000 and 200,000 years old. He says they would have accommodated truly enormous brains with a volume of 1700 to 1800 cubic centimetres – much larger than the 1350 cc of the average living human.
    Last year, he and his colleague Xiujie Wu at the Chinese Academy of Sciences placed these fossils and some others in a new species named Homo juluensis, which Bae is convinced is where the Denisovans really belong.

    “You just have to look at the molars,” says Bae. The unusually large teeth from Denisova cave are, he says, virtually indistinguishable from the teeth associated with the fossils he and Wu placed in H. juluensis. And while he accepts that the Harbin skull carries Denisovan-like DNA and protein signatures, he suspects that, if DNA can be extracted from some of the H. juluensis fossils, they will provide an even closer genetic match with the remains from Denisova cave.
    As things stand, then, there are now three potential ways to think about the Denisovans. The research community may begin to refer to them as H. longi or as H. juluensis – or a decision may be made to continue using the informal term Denisovan on the assumption that they really belong in H. sapiens. Currently, there is no consensus, but one is needed, says Bae. “You have to give them some kind of name because otherwise it’s really difficult to have a conversation about the variation and the evolutionary history of these human groups.”
    Names are particularly important in light of new research. In an as-yet-unpublished study, Ni and Stringer have teamed up, together with other colleagues, and used anatomical information from dozens of ancient fossils to reconstruct the evolutionary relationships among species in our human genus. The results led to a radical redrawing of our family tree (see diagram below). Traditionally, the Neanderthals have been viewed as the closest ancient humans to living people. But Ni and Stringer’s team concluded that Denisovans are more closely related to us than the Neanderthals are. According to their analysis, the Denisovans and modern humans last shared a common ancestor about 1.32 million years ago. The Neanderthals branched away from our evolutionary line earlier, around 1.38 million years ago.

    Ni and Stringer won’t discuss their conclusions until the work is accepted for publication in a scientific journal, but many researchers consider them to be controversial, given they clash with the DNA evidence. Not only does that DNA evidence suggest that Neanderthals and Denisovans are equally closely related to living humans, it also implies that the divergence between the Neanderthal-Denisovan line and our own occurred between 500,000 and 700,000 years ago – far more recently than Ni and Stringer’s team found.
    “It’s very clear from the genetic data that a major split between the lineages leading to modern humans on the one hand, and Denisovans/Neanderthals on the other, occurred within the last 500-700,000 years,” says David Reich at Harvard University.
    That being said, Aylwyn Scally at the University of Cambridge says such divergence estimates depend to some extent on the methods used to analyse the genetic data. José María Bermúdez de Castro at the National Human Evolution Research Centre (CENIEH) in Spain also thinks there is wiggle room on the divergence date. “The last common ancestor may be up to 1 million years old,” he says.
    Last common ancestor
    Conventionally, it is believed that this Ancestor X was located somewhere in Africa. But if Denisovans – a group that seems to have been largely confined to east Asia – emerged from the Ancestor X population too, an African location might seem less likely.
    Some researchers are already willing to entertain the idea that Ancestor X lived in Eurasia rather than in Africa. In a 2022 study, Bermúdez de Castro and María Martinón-Torres at CENIEH argued that south-west Asia might make more sense, particularly the Levantine region bordering the eastern Mediterranean Sea. “It’s the umbilical cord linking Africa to Eurasia,” says Bermúdez de Castro.

    Ancestor X might even have existed further east. In their yet-to-be-published study, Ni and Stringer’s team took a fresh look at two complete, but slightly squashed, ancient human skulls found in Yunxian, central China, about 35 years ago. They used software to create an undistorted model of one of the skulls, and realised that its anatomy was almost exactly in line with that expected of Ancestor X. For instance, it has features of our modern human face coupled with a more primitive-looking braincase that originally housed a brain of roughly 1140 cubic centimetres – smaller than that of the average living human.
    Moreover, its age – about 0.9 to 1.1 million years old – is roughly in line with the researchers’ estimate for when our last common ancestor with ancient humans roamed the world. As such, they reached a striking conclusion: this Yunxian skull came from a human very closely related to Ancestor X. What other researchers make of such a bold suggestion, however, remains to be seen.
    Denisovan behaviour
    With these ideas swirling around the research community, it has never been more important to understand the lives of the Denisovans. This is because assessing how much of a behavioural overlap there was between these ancient humans and our modern human ancestors could provide vital information about our own behavioural evolution.
    But it is difficult to conclude much about Denisovan behaviour without excavating sites that they occupied. We have known since 2010 that Denisova cave is one such location, but ancient DNA indicates that Neanderthals and modern humans also occupied the cave at various times during the Stone Age. This complicates things when it comes to interpreting the artefacts unearthed there, which include plenty of stone tools, bone needles for sewing and even ancient jewellery, such as an ivory tiara and a bracelet of polished green rock. Simply put, we don’t know which Stone Age humans made those artefacts.
    Other sites, however, are beginning to offer some insights into Denisovan lives. In 2022, for instance, a research team reported the discovery of a tooth with a Denisovan-like appearance in Tam Ngu Hao 2 – dubbed Cobra cave – in Laos. It suggested that some Denisovans adapted to humid tropical conditions quite unlike those found around Denisova cave – although such a conclusion was tentative given that it wasn’t possible to extract Denisovan-specific DNA or proteins from the tooth.
    But it is Baishiya Karst cave on the Tibetan plateau that is emerging as perhaps the most important Denisovan archaeological site. A study published last year concluded there is DNA evidence that the Denisovans – and no other humans – sporadically occupied the cave between 160,000 and 60,000 years ago.
    Excavations have yet to unearth anything as striking as the Denisova cave jewellery, but they are still revealing important information about the Denisovans. Perhaps most interesting is the fact that they occupied the cave at all given the extreme environment in which it is located. “It’s cold throughout the year,” says Dongju Zhang at Lanzhou University, China. “Snow covers the whole area in the wintertime, and you need a thick jacket even in July or August.”
    This fragment of mandible bone, found in Baishiya Karst cave in 1980, now turns out to have been from a DenisovanDongju Zhang, Lanzhou University
    Unsurprisingly, then, Zhang and her colleagues have found evidence that the Denisovans made fires inside the cave. It is also likely that they wore clothing to further protect themselves from the elements, with evidence that they skinned animals including the bharal (Pseudois nayaur), also known as the blue sheep. “We think they took the skins to cover their bodies and keep themselves warm,” says Zhang.
    Adding to the challenges the Denisovans faced is that the site is 3200 metres above sea level. “I was at the cave last year for a scientific workshop and the lack of oxygen is shocking – I got a horrible headache,” says Viola. Astonishingly, there are now hints that the Denisovans took to even higher altitudes: in as-yet-unpublished work, Zhang and her colleagues have found evidence of an ancient archaeological site on the Tibetan plateau at about 3700 metres above sea level.
    Hunting strategies
    Finding food on the plateau can be difficult because prey is thin on the ground. This may explain why Zhang and her colleagues discovered that the Denisovans at Baishiya Karst cave hunted a wide range of animals, including large mammals like the bharal and snow leopards as well as rodents such as marmots, and even birds. “It seems they had to use all the animal resources available to them,” says Zhang. To do so, the Denisovans must have developed a range of hunting strategies, because each of their prey species had a unique suite of behaviours.
    Collectively, these discoveries paint a picture of the Denisovans as remarkably adaptable. Indeed, some archaeologists have commented that their behavioural flexibility is strikingly reminiscent of modern humans.
    But even as we are finding echoes of ourselves in the Denisovans, we are also identifying subtle ways in which we differed from them. For instance, the stable isotopes in fossil teeth – which can reveal information about the variety of plants and animals an individual ate – suggest that modern humans adapted to hunt and forage in the rainforests of south and South-East Asia tens of thousands of years ago. But a 2023 analysis of the suspected Denisovan tooth from Cobra cave in Laos indicates that our ancient cousins lacked the tools and skill set to do so: they seem to have hunted only on nearby savannahs, says Mike Morley at Flinders University in Australia.
    Archaeological discoveries in the years ahead should help us more precisely define the similarities and differences between the Denisovans and modern humans. The odds of making such discoveries received a boost earlier this year. After analysing ancient proteins inside a jawbone dredged up off the west coast of Taiwan, a research team concluded that the bone came from a male Denisovan – providing the strongest fossil evidence yet that the Denisovans really did occupy a vast territory. “The geographic range for Denisovans was likely huge,” says Morley. “Just think how much more there must be to find.”

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    Did childcare fuel language? A new book makes the case

    Beekman suggests the complexity of childcare drove language’s spreadShutterstock/Artem Varnitsin
    The Origin of LanguageMadeleine Beekman (Simon & Schuster)
    Language is one of the few faculties that still seems to be uniquely human. Other animals, like chimpanzees and songbirds, have developed elaborate communication systems, but none appears to convey such a range and depth of meaning as ours. So how and why did our ancestors first develop language?
    Evolutionary biologist Madeleine Beekman has spent much of her career studying insects, especially bees. In her first book for a non-specialist audience, she branches out in a big way to propose an explanation for the evolution of human language.
    Her idea is that it evolved out of necessity, to enable us to cope with the demands of childcare. Compared with other mammals, human infants are exceptionally underdeveloped at birth, needing 24-hour care.
    Following in the footsteps of decades of palaeoanthropological research, Beekman links helpless babies to two features of human bodies: bipedality and large brains. “As our skeletons adjusted to walking upright, our hips became narrower,” she writes. Later, our brains also expanded. “Babies with a large head and mothers with narrow hips do not make a good combination,” Beekman observes, drily.
    To get around this “obstetrical dilemma”, babies are born early, before their heads get too big to squeeze through the birth canal. This enables humans to give birth relatively safely, at the cost of months spent caring for vulnerable infants.
    So far, so familiar. Beekman’s big leap is her proposal that the demands of looking after human babies drove the evolution of complex language. “Taking care of human infants is so singularly difficult that evolution had to craft a completely new tool to aid the effort,” she writes, and “the design fault that started the problem in the first place also provided its solution”. Our brains made birth harder, but they also enabled us to evolve a capacity for rich and flexible language.
    In proposing this idea, Beekman is wading into a very crowded marketplace. Many scenarios have been put forward for the evolution of language. Some say it developed in concert with technologies like stone tools: as we created more advanced tools, we needed more descriptive language to teach others how to make and use them. Or maybe language was a means of showing off, including through witty wordplay and insults. Then again, it might have allowed individuals to organise their own thoughts, and was only secondarily used to communicate with others.
    One appealing aspect of Beekman’s proposal is that it places women and children at the centre. Because science has traditionally been skewed towards the male, ideas about human evolution tended to overly focus on them (“Man the Hunter” and all that), despite the fact that some of the most dramatic changes in our evolution involved pregnancy.

    The author argues that language is only around 100,000 years old and is unique to our species

    It is good to consider the roles of women and children in the origin of language. However, this doesn’t necessarily mean that Beekman is right. She marshals intriguing evidence, notably that all large-brained birds, including parrots and New Caledonian crows, produce under-cooked offspring. Why? A 2023 study showed that the strongest predictor of brain size in birds was the amount of parental provisioning.
    This all sounds distinctly human-like and in line with Beekman’s narrative. But the biggest issue is timing. Humans have been bipedal for at least 6 million years and our brains grew rapidly from 2 million years ago. When, in this timespan, did childbirth become really difficult, and when did language evolve?
    Beekman argues that language is only around 100,000 years old and is unique to our species. She cites a 2020 study identifying “unique gene regulatory networks that affect the anatomical structures needed for the production of precise words”. These networks are apparently only present in our species, suggesting other hominins like Neanderthals couldn’t speak as well as humans.
    Beekman says this “nails it”, but other researchers have found evidence suggesting complex speech may have existed in other hominins. The evolution of human childbirth is equally tangled and uncertain. In short: nice idea, needs more evidence.
    Michael Marshall is a writer based in Devon, UK

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    Why bosses exploit their most loyal employees

    Ferran Traite Soler/Getty Images
    “I’ve always prided myself on my can-do attitude,” a reader told me this month. “Recently, however, I’ve started to feel resentful of the amount of work my boss puts at my door compared to colleagues. The more I do, the more he seems to expect of me, and I now feel that I’m cracking under the stress.”
    Our reader’s frustration is surely justified. A good work ethic should be one of the most highly prized – and rewarded – qualities in an employee. Everyday experience, though, reveals this is rarely the case. Indeed, according to studies by Matthew Stanley at the National University of Singapore and his colleagues, a pernicious bias can lead managers to exploit the very people they should be prizing.
    In one experiment, a group of managers were asked to read about a fictional employee named John, whose company was facing financial difficulties. They had to decide how willing they would be to give John extra hours and responsibilities without any extra pay. The researchers found that the managers were far more willing to do so if they learned that John had proved to be a loyal member of the team – compared with someone who was known to be more detached from their work.
    Further studies confirmed that small displays of loyalty encouraged managers to take this attitude: the more “John” gives, the more his managers will take. As Stanley and his co-authors note, this could create a “vicious cycle” of suffering – while less loyal workers manage to escape the sacrifices. But before you start viewing your boss too harshly, it is worth noting that Stanley and his colleagues don’t believe that the managers are conscious of their behaviour, instead regarding this as a form of “ethical blindness”.
    This may be compounded by the fact that many of us struggle to turn down extra responsibilities for fear of seeming disagreeable. If we are to break free from that pattern of behaviour, we need to learn how to say no. Research by Vanessa Bohns at Cornell University in New York state suggests it is easier to do so by email than in voice-to-voice or face-to-face conversations. If the request comes in person, or on the phone, I have found that it helps to ask whether you can check your schedule before agreeing. That small delay should prevent a knee-jerk “yes”, and if you want to refuse, it gives you time to formulate a polite response. Try to use assertive language. Saying “I don’t have time” is more persuasive than “I can’t make time”, for example, since it is simply reflecting the reality of your situation, rather than apologising for your inability to create more hours in the day.
    But I can’t help think the onus should be on our managers to change their behaviour. A little self-awareness about their tendency to exploit their hardest workers might lead them to rethink how they reward that loyalty.

    Vanessa Bohns’s book You Have More Influence Than You Think (W. W. Norton) explores the psychology and ethics of compliance, including many strategies to become more assertive.

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    David Robson is an award-winning science writer and author of The Laws of Connection: 13 social strategies that will transform your life

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    Introvert, extravert, otrovert? There’s a new personality type in town

    Elaine Knox
    When I was growing up, it was customary for children to join the scouts once they reached fifth grade, around the age of 9 or 10. My parents bought me the scout uniform with the matching scarf and leather loop to fasten it around the collar, and I still remember feeling special and grown-up as I wore the uniform to the local scouts chapter.
    We all formed a circle, sitting cross-legged on the ground as the group leader sat on a small stool and addressed us very seriously. When he finished talking about what it meant to be a junior scout, he told us to stand to attention as he recited the scouting pledge, and we repeated it solemnly after him.

    As I said the words out loud, I knew for the first time that I was different. While the other kids seemed awed by this initiation – by the sacred bond forged with their fellow inductees and all those who had come before them – I felt nothing. They were just words.
    Most people find it hard to imagine what it is like to not feel any particular affinity or loyalty towards any group. This is so unusual that it is understood by some as a psychological problem to be treated. However, over my 40 years as a clinical psychiatrist I have realised that for many of my patients (and for me) disinterest in group membership and assimilation isn’t a psychological problem – it is simply a personality type that hasn’t been recognised before.
    Otroverts is the term I use for those who don’t feel the obligation to merge their identities with others. We are all born as otroverts, before the cultural conditioning of childhood cements our affiliations with various identities and groups.
    Being unable to adopt a group identity can have social consequences in a culture that is designed for joining. However, it can also be quite advantageous. When you don’t belong to any group, you aren’t subject to the group’s implicit rules or swayed by its influence. This confers two beneficial traits: originality and emotional independence.
    Being outside the hive, so to speak, allows you to think and create freely: to come up with unique ideas, untainted by groupthink or by what has come before. Able to distinguish between the gravitational pull of the group consensus and your own inner, personal centre of gravity, you are free to think whatever you want and to be flexible when situations change, without fear of subverting collective notions about what makes an idea “good”.
    Given that you can’t be cast out of a group to which you don’t belong, you have no fear of such social rejection. You don’t seek external validation, nor do you rely on others for emotional support. You don’t feel the need to convince anyone of anything, least of all your own worth.

    Our communal society often conflates belonging with connection. However, while it is true that people who struggle to connect might find it hard to achieve a sense of belonging, it isn’t true that not belonging means no connections at all. In fact, without the noise of popular culture, gossip, family conflicts or political tribes (all disinteresting to otroverts), you are free to focus on deepening bonds with the people you feel genuinely close to.
    History is full of independent thinkers who aren’t emotionally dependent on any group and can therefore see the fanaticism of a hive mind long before most people do: George Orwell comes to mind.
    Sadly, it often seems that people need to emerge from the ashes of self-destructive groupthink before they realise that individual thinkers can be right.
    Perhaps we can learn from otroverts that, while there are many reasons to praise community, we should also be acutely aware of its darker side – tribalism.
    Rami Kaminski is a psychiatrist and author of The Gift of Not Belonging

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    Fossil teeth may come from a new species of early hominin

    A model of an Australopithecus homininCredit: Cro Magnon/Alamy
    Thirteen hominin teeth have been discovered in Ethiopia in layers of volcanic ash between 2.6 and 2.8 million years old. The researchers think some of the teeth belong to one of the earliest members of the Homo genus, while others appear to be from a new hominin, suggesting both species lived alongside each other.
    “They either shared resources, and everything was hunky-dory, or maybe one of them was marginalised,” says Kaye Reed at Arizona State University. “We just don’t know at this point.”

    Previous discoveries show that before around 3 million years ago, several species of early hominins in the genus Australopithecus lived in this region, including Australopithecus afarensis, the species to which the famous Lucy fossil belonged.
    From around 2.5 million years ago, the first hominins from the genus Homo start appearing, with features more similar to those of modern humans. So what happened in between? To find out, Reed and her colleagues have been digging in an area called Ledi-Geraru, where there are volcanic deposits from this crucial time.
    In 2013, her team found a 2.8-million-year-old jaw that appears to be from a Homo species, pushing back the origin of this genus. Now her team has found 13 teeth in three different layers of ash.

    The teeth in the oldest and the youngest layers – which are dated to 2.79 and 2.59 million years ago – also belong to the genus Homo, according to the team. But they think the teeth in the middle layer – which is dated to 2.63 million years – are from an Australopithecus. The sites are all within a kilometre of each other.
    “We were expecting to find more of our genus Homo, and then we found Australopithecus as well,” says Reed.
    Molar teeth from Ledi-Geraru, which may come from an unknown species of AustralopithecusBrian Villmoare: University of Nevada Las Vegas
    What’s more, the Australopithecus teeth are different enough from those of A. afarensis and other australopithecines that the team thinks it is probably a new species. If they are right, it means the evolutionary tree leading to modern humans is bushier and more complex than we thought.
    It is a great discovery, says John Hawks at the University of Wisconsin–Madison, but it is hard to draw conclusions based on a few teeth.
    “When you find evidence that spans 200,000 years, as these teeth do, you can’t be sure that they lived at the same time,” says Hawks. “That’s a huge amount of time.”

    The identification of the teeth as separate species is also questionable. “Many fossils that we find combine features that are sometimes found in different species. You can always take a small sample and break it up into the most Homo-like and most Australopithecus-like,” says Hawks.
    “The question is what, statistically, you can say, and in this case the statistics on size measurements don’t show that the teeth are very different from each other. They’re in the range of overlap of early Australopithecus species and early Homo species.”

    Neanderthals, ancient humans and cave art: France

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    DNA analysis reveals West African ancestry in early medieval England

    The skeleton of a girl from Updown cemetary, who was found to have West African ancestryM George et al.
    Two unrelated young people buried in cemeteries in England in the Early Middle Ages probably had grandparents from West Africa. How and when their relatives arrived in Britain is unknown, but the discovery implies that migrants in Anglo-Saxon times were coming from much further afield than previously thought.
    After the Romans finally withdrew from Britain in AD 410, Britain was invaded and settled by Germanic Angles, Saxons and Jutes. To investigate whether people also arrived from elsewhere, Duncan Sayer at the University of Central Lancashire, UK, and his colleagues have analysed ancient DNA from the bones of people buried in two 7th-century cemeteries on England’s southern coast.

    One of them is in Updown in Kent, where many traded objects from around the world have been found, including pots, buckles and brooches from Frankish Gaul, and garnets in jewellery that may have come from India. The people in the cemetery were often buried with items like cookware, cutlery or combs.
    The other cemetery is in Worth Matravers, Dorset, further west. The people there are buried in a Romano-British manner, with few grave goods.
    The majority of those in the cemeteries had, as expected, either northern European or western British and Irish ancestry, but a girl at Updown and a young man at Worth Matravers had a recent ancestor, likely a grandparent, from West Africa.

    In both cases, the mitochondrial DNA, which is passed down from the mother, was northern European, but the autosomal DNA, which comes from both parents equally, had 20 to 40 per cent ancestry akin to that of the present-day Yoruba, Mende, Mandinka and Esan groups from sub-Saharan West Africa.
    This means the West African DNA probably comes from a grandfather – and it is the first evidence for genetic connections between Britain and Africa during the Early Middle Ages.
    Both young people were buried as typical members of the community. The DNA analysis also showed that two relatives of “Updown Girl”, who was about 11 to 13 years old when she died, are in the same cemetery: a grandmother and an aunt.
    Looking at the ratios of isotopes of carbon and nitrogen in a bone sample from the Worth Matravers youth, who was aged between 17 and 25 when he died, showed what he had eaten when the bones were forming.
    “From his diet, it looks like he was born and raised in England,” says team member Ceiridwen Edwards at the University of Huddersfield, UK.
    There is evidence for African DNA in York in the Roman period, says Edwards. However, Sayer thinks the proportion of West African DNA in the youngsters in the cemeteries would be far lower if they were descendants of people from the days of Roman rule. “This is a grandparent, so it’s definitely not about surviving Roman military or administrators, which were several hundred years in the past,” he says.

    There is also no evidence to suggest that these people were slaves, says Sayer: “These individuals are being buried as fully fledged members of their community.”
    Instead, he suggests, this is to do with trading and the movement of goods and people. At some point, people from West Africa had come to Britain, perhaps on a trading ship, and stayed.
    Sayer thinks their arrival may have been linked to the reconquest of North Africa by the Byzantine Empire, also known as the Eastern Roman Empire, in the 6th century. That military action was taken to get access to gold from sub-Saharan Africa. “The reopening of this channel is taking place at a time that would correspond very much with the grandparents of these two people,” he says.
    “This work exemplifies how dynamic the post-[Western] Roman and early medieval periods were in Britain,” says Marina Soares Da Silva at the Francis Crick Institute in London. “The authors propose trading routes facilitated by the Byzantine Empire rule in North Africa, and I think that’s a valid possibility.”
    Seventh-century England was certainly no “dark age” collection of small, rural, isolated communities, says Sayer. “These are dynamic communities with artefacts being traded, and gene flow taking place, all the way from West Africa and beyond.”

    Historic Herculaneum – Uncovering Vesuvius, Pompeii and ancient Naples

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    Why a mysterious group of ancient humans doesn’t have a species name

    Illustration of an ancient Denisovan manJOHN BAVARO FINE ART/SCIENCE PHOTO LIBRARY
    This is an extract from Our Human Story, our newsletter about the revolution in archaeology. Sign up to receive it in your inbox every month.
    One of the things I try to do in Our Human Story is answer the most commonly asked questions about human evolution. Back in February 2021, I tried to explain something that bugs a lot of people: how Neanderthals and modern humans could interbreed if they were separate species. (Short answer: the boundaries between species are fuzzy).
    This month we’re going to tackle another perennial source of confusion. Why don’t the Denisovans, an extinct human group that was once widespread in Asia, have a species name? And what should their name be, if they ever get one?

    The question of what the Denisovans’ “official” name should be has been rumbling on ever since they were discovered in 2010. It came up again in June, when a major discovery was announced. A skull from Harbin in North China, dubbed the Dragon Man, had been identified as a Denisovan using molecular evidence. We had never had a Denisovan skull before, so this was the first time we had a good idea of what their faces were like.
    When I went on New Scientist’s podcast The World, the Universe and Everything to talk about the find, host Rowan Hooper asked me why the Denisovans don’t have a species name. Why can’t we call them Homo denisovanensis or something, the way we call Neanderthals Homo neanderthalensis?

    Time was short, so I gave what I hoped was a simple answer: “It comes down to the fact that we have never had enough information about the Denisovans to be able to describe them properly… Their DNA is as different from Neanderthals as Neanderthal DNA is from us. Just on that basis, they’re different enough to count as a new species. But that’s not enough, according to the official rules of scientific taxonomy. You can’t just say, ‘That’s a new species’. You actually have to be able to describe in detail what the species looked like, what its skeleton was like. And we’ve just never had that.”
    While that’s true, there’s also a lot more to it. There are two entangled questions. First, which fossils are actually Denisovans (and which aren’t)? That’s a question about objective reality, and very tricky to resolve, because it involves considering dozens of fossils and decades of research. Second, which of the many names that have been assigned should actually take precedence according to our rules of taxonomy? That’s a legalistic question about human processes – and thus even trickier.
    Who’s in and who’s out?
    First, here’s a reminder about the Denisovans. They’re a mysterious group of humans, first described in 2010 on the basis of a sliver of finger bone found in Denisova cave in the Altai mountains of Siberia. DNA from the bone revealed it was neither a modern human nor a Neanderthal, but something different. Furthermore, many people today carry some Denisovan DNA, especially in South-East Asia and Melanesia – indicating that Denisovans and modern humans interbred.
    This implied that Denisovans must have been fairly widespread in east Asia within the last few hundred thousand years. So where are all the Denisovan fossils?
    Fast forward 15 years to the present, and a small number of Denisovan fossils have been positively identified. For instance, a lower jawbone was found in a cave on the Tibetan plateau, and was identified using both proteins from the fossil and DNA from sediments. Likewise, a jawbone was dredged from the Penghu channel off the coast of Taiwan: in April, preserved proteins confirmed it was Denisovan.
    Still, we are a long way from having a complete skeleton. The identification of the Harbin skull as a Denisovan took us a step closer by giving us a face. But there’s still a whole lot of skeleton still to find.
    Now, there are a great many hominin fossils from East Asia that could, in theory, be Denisovan. Many of the finds have proved hard to classify: they don’t seem to quite match modern humans, or Neanderthals or any of the other established species like Homo erectus. This is enticing: if enough of them prove to be Denisovan, we’ll have a much more complete picture and maybe we could formally describe the species.
    But how do we decide which fossils are Denisovan? Ideally, we’d have molecular evidence – preserved DNA or proteins – we could compare to the original Denisovan remains. But most of the specimens either haven’t been analysed or haven’t yielded anything.

    One of the most prominent attempts to solve this problem was a preliminary study posted in 2024, with revisions in March, by a group led by Xijun Ni at the Chinese Academy of Sciences in Beijing. The team compared 57 hominin fossils, looking at as many physical traits as possible. This enabled them to draw up a family tree of all the various fossils.
    Ni’s team found Eurasian hominins clustered into three main groups: modern humans, Neanderthals and a third group. This third group included the original Denisovan fossils, the jawbone from the Tibetan cave, the Penghu jawbone and the Harbin skull. It seems like the third group is the people we’ve been calling the Denisovans.
    This is very neat if it’s true – but of course others disagree.
    One contentious set of fossils comes from Hualongdong in South China. It’s a good collection: a nearly-complete skull with 14 teeth, an upper jaw, six isolated teeth and other bits. They’re all about 300,000 years old.
    Ni’s team identified the Hualongdong fossils in the Denisovan group. However, a study in July led by Xiujie Wu, also at the Chinese Academy of Sciences, took a close look at the Hualongdong teeth. It found they didn’t match anything terribly well, and suggested they might represent yet another group. Of course, there’s another possible explanation: Denisovans were surely diverse, so maybe the Hualongdong Denisovans were a bit different from those elsewhere.
    Meanwhile, there are many other mysterious Asian fossils, including the 260,000-year-old Dali skull and the also-260,000-year-old Jinniushan partial skeleton – both of which Ni’s team suggested were Denisovan.
    At any rate, we have a growing list of Denisovan fossils, some more confidently identified than others. What are we going to call them?
    The Harbin skullHebei GEO University
    Homo whatever
    It so happens Ni was one of the researchers that described the Harbin skull in 2021. The team named it Homo longi. So maybe that’s what we ought to call the Denisovans?
    But wait. A competing proposal was put forward last year, by Wu and Christopher Bae at the University of Hawai’i at Mānoa in Honolulu. In two papers, in Paleoanthropology and Nature Communications, they argued we should instead build a species around a set of fossils from Xujiayao in northern China. They proposed calling this new species Homo juluensis and including the original Denisovan fossils. So we should call the Denisovans Homo juluensis.
    The selling point of this idea is the Xujiayao fossils do resemble the Denisovan fossils. In fact, Ni’s team also classed them as Denisovan. The difference is Bae and Wu wanted to treat the Xujiayao fossils as the “type specimen”, the one that the entire species gets named after.
    This is simultaneously an argument about which fossils should be grouped together and about naming conventions. Let’s separate the two.
    On the first front, the Homo juluensis proposal has a big problem. Bae and Wu explicitly said the Harbin skull isn’t a Homo juluensis/Denisovan, because it doesn’t look similar enough. However, the study from June clearly shows, using molecular evidence, the Harbin skull is a Denisovan. So as a description of the objective reality – which fossils are and are not Denisovan – Homo juluensis seems to have fallen flat.
    What about taxonomy? The rules here are complicated. One key element is, essentially, first come first served: the first name to be applied is considered to have priority. On this basis, Homo longi has the advantage over Homo juluensis, because it was put forward three years earlier.
    Are there any other possible names for the Denisovans?
    The excavators of Denisova cave never formally described the Denisovans as a species. One member of that team, Anatoly Derevianko, referred to them as Homo sapiens altaiensis, which would make them a subspecies of modern human – but he didn’t do a formal description so it apparently doesn’t count.

    This year, Derevianko has put out a series of papers proposing what Denisovans might have done in Mongolia, Uzbekistan, Tajikistan and Iran. He refers to them throughout as Homo sapiens denisovan. I haven’t been able to read the papers as only the abstracts are publicly available, so I don’t know if he has provided a formal description – but if he did, he did so four years after Homo longi was named.
    If you really dig around, you can find a few more options. A 2015 paper uses Homo denisovensis and a 2018 study plumps for Homo denisensis. Neither has been widely accepted.
    Finally, there’s the possibility of a really old name. Maybe someone named one of the Asian hominin fossils decades ago in an obscure paper: if that fossil turns out to be Denisovan, that name would have priority (assuming the description was done properly). However, Wu, Bae, Ni and others looked into this in a 2023 paper. They found key fossils were never properly named. There had been loose suggestions that, for example, the Dali skull could be called Homo daliensis, but these were throwaway remarks rather than formal descriptions.
    At this point your head is probably spinning from all these fossil names and species names, so let’s sum up. The main point is we are fleshing out our understanding of the Denisovans – and that means we’re getting closer to being able to give them a taxonomic name.
    For what it’s worth, based on my understanding of taxonomic rules, I think Homo longi has a good chance of becoming the official name. I’m not sure it would have been my choice, but it isn’t up to me. In any case, they’ll always be the Denisovans to me.

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    Human bones found in Spanish cave show signs of ancient cannibalism

    Cut marks on a foot bone from El Mirador cave in SpainIPHES-CERCA
    Butchered human remains found in a cave in northern Spain suggest that Neolithic people may have eaten their enemies after killing them in combat.
    Francesc Marginedas at the Catalan Institute of Human Paleoecology and Social Evolution (IPHES) in Tarragona, Spain, and his colleagues studied 650 fragments of human remains belonging to 11 people, which were found in El Mirador cave in the Atapuerca mountains and dated back 5700 years.

    All of the bones had signs that these individuals had been eaten by fellow humans. Some had chop marks, indicating that the people’s skin was cut off with stone tools, while others were translucent with slightly rounded edges, suggesting they had been boiled. Some of the longer bones had been broken open with stones, probably to extract and eat the marrow, while smaller ones like metatarsals and ribs featured human teeth marks.
    The study adds to evidence that cannibalism was more common than previously thought throughout human history.
    El Mirador is at least the fifth site with strong evidence of cannibalism in Spain in the Neolithic period, when people switched from foraging to farming, says Marginedas. “We are really starting to see that this kind of behaviour was more common than what we expected.”

    Why humans ate each other so much is less certain. At some sites, evidence including skull cups suggests that cannibalism may have had a ceremonial purpose. At others, it appears to have been a means of survival during extreme famine.
    Marginedas and his colleagues say the evidence at El Mirador instead points to war. An abundance of animal remains and no signs of nutritional stress in the humans indicate this early farming community didn’t face famine, the researchers say. They found no telltale signs of ritual, with the human remains mixed in with animal bones.
    The age of the individuals ranged from under 7 to more than 50 years old, suggesting a whole family had been wiped out in conflict. Radiocarbon dating revealed that all 11 people were probably killed and eaten in a matter of days.
    The researchers say this mirrors signs of conflict and cannibalism also seen at two other Neolithic sites: Fontbrégoua cave in France and Herxheim in Germany. This period increasingly looks like it was defined by instability and violence, as communities clashed with neighbours or newly arrived settlers over territory.

    Marginedas and his colleagues are less sure why these people then ate their adversaries, but ethnographical studies of humans eating each other in war throughout history suggest cannibalism was a form of “ultimate elimination”. “We think this one group killing the other group and then consuming it is a way of humiliating them,” says Marginedas.
    “The degree to which the remains were processed and consumed is striking,” says Paul Pettitt at Durham University in the UK. “Whether or not they were consumed by kin or strangers, the violence practised on these remains is redolent of a process of dehumanisation during the process of consumption.”
    Silvia Bello at the Natural History Museum in London agrees the deaths were probably the result of conflict, but isn’t convinced they were eaten as a form of humiliation. While the cannibalism may have been fuelled by aggression or hatred rather than kindness, as one would expect in funerary practices, it could still have been ceremonial, she says.
    “I think it could be more complicated. Even if it was warfare, the fact that they eat them still has a sort of ritualistic meaning,” she says.

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