The Great London:
Early Humans

Modern humans have been blamed for killing off the Neanderthals by out competing them, breeding with them and even outright murdering them.

But new research suggests it may actually have been infectious diseases carried by our modern ancestors as they migrated out of Africa that finished them off.

Scientists studying the latest genetic, fossil and archaeological evidence claim that Neanderthals suffered from a wide range of diseases that still plague us today.

They have found evidence that suggests our prehistoric cousins would have been infected by diseases such as tuberculosis, typhoid, whooping cough, encephalitis and the common cold.

But anthropologists from Cambridge University and Oxford Brookes University say that new diseases carried by modern humans may have led to the downfall of Neanderthals.

They speculate that pathogens like Heliocbacter pylori, the bacteria that causes stomach ulcers, were brought to Europe by modern humans from Africa and may have infected Neanderthals, who would have been unable to fight off these new diseases.

However, Neandethals may have also helped modern humans by passing on slivers of immunity against some diseases to our ancestors when they interbred.

Dr Simon Underdown, a principal lecturer in anthropology at Oxford Brookes University and co-author of the study, said: 'As Neanderthal populations became more isolated they developed very small gene pools and this would have impacted their ability to fight off disease.

'When Homo sapiens came out of Africa they brought diseases with them.

'We know that Neanderthals were actually much more advanced than they have been given credit for and we even interbred with them.

'Perhaps the only difference was that we were able to cope with these diseases but Neanderthals could not.'

The findings add to a growing body of evidence that Neanderthals were not as different from modern humans as was originally thought.

Recent discoveries have suggested that rather than being brutish cavemen, Neanderthals had sophisticated culture, were master tool makers and may even have had their own language.

The new study suggests that Neanderthals also suffered from many of the same afflictions and complaints that modern humans experience.

Indeed, there is some evidence from caves that early humans may have burned their bedding in a bid to rid themselves of infestations of lice or bed bugs.

Dr Underdown and his colleague Dr Charlotte Houldcroft, a researcher in infectious diseases at Cambridge University and University College London, analysed recent genetic studies on Neanderthals and other early humans.

They also examined recent genetic research on common human pathogens that have aimed to trace their origins and combined it with fossil and archaeological evidence.

Most evidence from the fossil record suggest that Neanderthals tended to suffer traumatic injuries as a result of their hunter gatherer lifestyle, but there are also signs of inflammation and infection.

Their study, which is published on the open source database bioRxiv, contradicts the common view that infectious diseases only really became a problem for humans in the Holocene about 11,000 years ago when humans began living in dense settlements and farming livestock.

Instead, they say many of the diseases we see around us today were common during the pleistocene when Neanderthals dominated much of Europe and Asia between 250,000 and 45,000 years ago, when they disappeared.

They say pathogens like TB, typhoid and Crimean fever that were thought to be zoonoses caught from herd animals may have actually originated in humans and were only passed to animals during the rise of farming around 8,000 years ago.

Genetic sequencing of Neanderthal and Denisovan - another early human ancestor - DNA has shown that modern humans have inherited a number of genes from these extinct species.

These include genes that provide immunity to viral infections such as tick-borne encephalitis.

Dr Underdown said this virus would probably have been common in the forested areas of northern Europe that Neanderthals inhabited and so immunity would have been an advantage.

Other genes found in modern Papua New Guineans that are involved in the immune response against viruses like dengue and influenza may have come from Neanderthals.

Analysis of ancient DNA has also shown that Neanderthals carried genes that would have protected them against bacterial blood poisoning, or sepsis.

Dr Underdown said: 'There are genetic signals in the Neanderthal genome that suggest quite clearly that they were exposed to these types of diseases but also developed some resistance to them.

'It had been thought that many of these diseases began infecting humans with the population increases that came with domestication of animals and permanent settlements.

'Be here we have got Neanderthals being infected by these diseases long before those developments.'

Author: Richard Gray | Source: Daily Mail Online [April 03, 2015]

New research led by the University of Southampton shows Neanderthals kept coming back to a coastal cave site in Jersey from at least 180,000 years ago until around 40,000 years ago.

As part of a re-examination of La Cotte de St Brelade and its surrounding landscape, archaeologists from Southampton, together with experts from three other universities and the British Museum, have taken a fresh look at artefacts and mammoth bones originally excavated from within the site's granite cliffs in the 1970s. Their findings are published in the >journal Antiquity.

The researchers matched types of stone raw material used to make tools to detailed mapping of the geology of the sea bed, and studied in detail how they were made, carried and modified. This helped reconstruct a picture of what resources were available to Neanderthals over tens of thousands of years -- and where they were travelling from.

Lead author Dr Andy Shaw of the Centre for the Archaeology of Human Origins (CAHO) at the University of Southampton said: "La Cotte seems to have been a special place for Neanderthals. They kept making deliberate journeys to reach the site over many, many generations. We can use the stone tools they left behind to map how they were moving through landscapes, which are now beneath the English Channel. 180,000 years ago, as ice caps expanded and temperatures plummeted, they would have been exploiting a huge offshore area, inaccessible to us today."

Previous research focussed on particular levels in the site where mammoth bones are concentrated, but this new study took a longer-term perspective, looking at how Neanderthals used it and explored the surrounding landscape for over 100,000 years.

The team, including academics from the British Museum, University College London (UCL) and the University of Wales found that Neanderthals kept coming back to this particular place, despite globally significant changes in climate and landscape. During glacial phases (Ice Ages), they travelled to the site over cold, open landscapes, now submerged under the sea. They kept visiting as the climate warmed up and Jersey became a striking highpoint in a wide coastal plain connected to France.

Dr Beccy Scott of the British Museum added: "We're really interested in how this site became 'persistent' in the minds of early Neanderthals. You can almost see hints of early mapping in the way they are travelling to it again and again, or certainly an understanding of their geography. But specifically what drew them to Jersey so often is harder to tease out. It might have been that the whole Island was highly visible from a long way off -- like a waymarker -- or people might have remembered that shelter could be found there, and passed that knowledge on."

Paper author Dr Matt Pope, of the Institute of Archaeology at UCL, agrees: "La Cotte de St Brelade is probably the most important Neanderthal site in northern Europe and could be one of the last known places that Neanderthals survived in the region. It was certainly as important to them as it is to us, as we try and understand how they thrived and survived for 200,000 years.

"With new technology we have been able to reconstruct the environment of the La Cotte Neanderthals in a way earlier researchers couldn't. Our project has really put the Neanderthal back into the landscape, but emphasised how significant the changes in climate and landscape have been since then."

Project leader Professor Clive Gamble, of CAHO at the University of Southampton, comments: "Jersey is an island that endures, summed up by the granite cliffs of St Brelade's Bay. The elements which led to Neanderthals coming back for so many thousands of years shows how this persistence is deep rooted in Jersey's past. Our project has shown that more unites the past with the present than separates. We are not the only humans to have coped successfully with major environmental changes. Let's hope we are not the last."

The team's work was undertaken as part of the 'Crossing the Threshold' project led by Professor Clive Gamble and Dr John McNabb at the University of Southampton, together with UCL and the British Museum. The research was funded by the Arts and Humanities Research Council and looks at major changes in how early humans used places from 400,000 years ago.

Source: University of Southampton [December 12, 2016]

Human teeth discovered in southern China provide evidence that our species left the African continent up to 70,000 years earlier than prevailing theories suggest, a study published on Wednesday said.

Homo sapiens reached present-day China 80,000-120,000 years ago, according to the study, which could redraw the migration map for modern humans.

"The model that is generally accepted is that modern humans left Africa only 50,000 years ago," said Maria Martinon-Torres, a researcher at University College London and a co-author of the study.

"In this case, we are saying the H. sapiens is out of Africa much earlier," she told the peer-reviewed journal Nature, which published the study.

While the route they travelled remains unknown, previous research suggests the most likely path out of East Africa to east Asia was across the Arabian Peninsula and the Middle East.

The findings also mean that the first truly modern humans -- thought to have emerged in east Africa some 200,000 years ago -- landed in China well before they went to Europe.

There is no evidence to suggest that H. sapiens entered the European continent earlier than 45,000 years ago, at least 40,000 years after they showed up in present-day China.

The 47 teeth exhumed from a knee-deep layer of grey, sandy clay inside the Fuyan Cave near the town of Daoxian closely resemble the dental gear of "contemporary humans," according to the study.

They could only have come from a population that migrated from Africa, rather than one that evolved from an another species of early man such as the extinct Homo erectus, the authors said.

The scientists also unearthed the remains of some 38 mammals, including specimens of five extinct species, one of them a giant panda larger than those in existence today.

No tools were found.

"Judging by the cave environment, it may not have been a living place for humans," lead author Wu Liu from the Chinese Academy of Science in Beijing told AFP.

The study, published in the journal Nature, also rewrites the timeline of early man in China.

Up to now, the earliest proof of H. sapiens east of the Arabian Peninsula came from the Tianyuan Cave near Beijing, and dated from no more than 40,000 years ago.

The new discovery raises questions about why it took so long for H. sapiens to find their way to nearby Europe.

"Why is it that modern humans -- who were already at the gates -- didn't really get into Europe?", Martinon-Torres asked.

Wu and colleagues propose two explanations.

The first is the intimidating presence of Neanderthal man. While this species of early human eventually died out, they were spread across the European continent up until at least some 50,000 years ago.

"The classic idea is that H. sapiens... took over the Neanderthal empire, but maybe Neanderthals were a kind of ecological barrier, and Europe was too small a place" for both, Martinon-Torres said.

Another impediment might have been the cold.

Up until the Ice Age ended 12,000 years ago, ice sheets stretched across a good part of the European continent, a forbidding environment for a new species emerging from the relative warmth of East Africa.

"H. sapiens originated in or near the tropics, so it makes sense that the species' initial dispersal was eastwards rather than northwards, where winter temperatures rapidly fell below freezing," Robin Dennell of the University of Exeter said in a commentary, also in Nature.

Martinon-Torres laid out some of the questions to be addressed in future research, using both genetics and fossil records.

"What are the origins of these populations, and what was their fate? Did they vanish? Could they be the ancestors of later and current populations that entered Europe?"

She also suggested there might have been "different movements and migrations" out of Africa, not just one.

Besides the prehistoric panda, called Ailuropoda baconi, the scientists found an extinct species of a giant spotted hyaena.

An elephant-like creature called Stegodon orientalis and a giant tapir, also present, were species that may have survived into the era when the Chinese had developed writing, some 3500 years ago.

The cache of teeth nearly went unnoticed, Wu told AFP.

He and his Chinese colleagues discovered the cave -- and its menagerie of long-deceased animals -- in the 1980s, but had no inkling that it also contained human remains.

But 25 years later, while revisiting the site, Wu had a hunch.

"By thinking about the cave environment, we realised that human fossils might be found there," he told AFP by email. "So we started a five-year excavation."

Author: Marlowe Hood | Source: AFP [October 14, 2015]

Analysis of ancient cadavers recovered at a famous archaeological site confirm the existence of a sophisticated culture of butchering and carving human remains, according to a team of scientists from the Natural History Museum, University College London, and a number of Spanish universities.

Gough's Cave in Somerset was thought to have given up all its secrets when excavations ended in 1992, yet research on human bones from the site has continued in the decades since.

After its discovery in the 1880s, the site was developed as a show cave and largely emptied of sediment, at times with minimal archaeological supervision.

The excavations uncovered intensively-processed human bones intermingled with abundant butchered large mammal remains and a diverse range of flint, bone, antler, and ivory artefacts.

New radiocarbon techniques have revealed remains were deposited over a very short period of time, possibly during a series of seasonal occupations, about 14,700 years ago.

Dr Silvia Bello, from the Natural History Museum's Department of Earth Sciences, lead researcher of the work said, "The human remains have been the subject of several studies. In a previous analysis, we could determine that the cranial remains had been carefully modified to make skull-cups. During this research, however, we've identified a far greater degree of human modification than recorded in earlier. We've found undoubting evidence for defleshing, disarticulation, human chewing, crushing of spongy bone, and the cracking of bones to extract marrow."

The presence of human tooth marks on many of the bones provides incontrovertible evidence for cannibalism, the team found. In a wider context, the treatment of the human corpses and the manufacture and use of skull-cups at Gough's Cave has parallels with other ancient sites in central and western Europe.

But the new evidence from Gough's Cave suggests that cannibalism during the 'Magdalenian period' was part of a customary mortuary practice that combined intensive processing and consumption of the bodies with the ritual use of skull-cups.

Simon Parfitt, of University College London, said, "A recurring theme of this period is the remarkable rarity of burials and how commonly we find human remains mixed with occupation waste at many sites. Further analysis along the lines used to study Gough's Cave will help to establish whether the type of ritualistic cannibalism practiced there is a regional ('Creswellian') phenomenon, or a more widespread practice found throughout the Magdalenian world."

Source: Natural History Museum [April 16, 2015]

Analysis of the first fossil bee nest from the Plio-Pleistocene of South Africa suggests that the human ancestor Australopithecus africanus lived in a dry savannah environment, according a study published in the >open-access journal PLOS ONE by Jennifer Parker from University College London, United Kingdom, and colleagues.

Little paleoecological information is available for the site in South Africa where the first Au. africanus fossil—the 'Taung Child'—was discovered. However, insect-related fossils, abundant at the discovery site, can yield insights into the paleoenvironment. Bees, for example, tend to build characteristic nests in characteristic conditions. Parker and colleagues analyzed CT scans of a fossil bee nest that was discovered near the Taung Child site to determine its internal structure and thus the kinds of bees that built it.

The fossil nest was exceptionally well preserved, and the structure of its cells and tunnels suggested that it was made by a ground-nesting solitary bee. These bees typically nest on bare, light, dry soil that is exposed to the sun, which bolsters other recent evidence that Au. africanus lived in dry savannahs. Insect-related fossils are common but largely overlooked at sites where human ancestors lived, the researchers said, and their work underscores the contribution such fossils can make to understanding the environments where human ancestors lived.

"When Raymond Dart published his description of the 'Taung Child' in 1925 he profoundly changed our understanding of human evolution," says study co-author Philip Hopley. "In the 90 years following his discovery, attention of anthropologists has moved to other African sites and specimens, and research at Taung has been hampered by the complex geology and uncertain dating. New research at Taung is helping to reconstruct the environment in which this enigmatic little hominin lived and died."

Source: Public Library of Science [September 29, 2016]

A research team led by scientists of the Max Planck Institute for Evolutionary Anthropology scanned the skulls of Neandertals and found the small middle ear ossicles, which are important for hearing, still preserved within the cavities of the ear. To their surprise, the Neandertal ossicles are morphologically distinct from the ossicles of modern humans. Despite the differences in morphology, the function of the middle ear is largely the same in the two human species.

The authors relate the morphological differences in the ossicles to different evolutionary trajectories in brain size increase and suggest that these findings might be indicative of consistent aspects of vocal communication in modern humans and Neandertals. These findings are also of importance for shedding light on the emergence of human spoken language, which can only be inferred indirectly from the archaeological and fossil record.

The three bones of the middle ear (hammer, anvil, stapes) make up the ossicular chain. This bony chain, which is found in all mammals is dedicated to the transmission of sound waves from the tympanic membrane to the inner ear and helps in amplifying the energy of airborne sound in order to allow the sound wave to travel within the fluid-filled inner ear.

Moreover, the ear ossicles are not only important for correct hearing but are also the smallest bones of our body. Thus, it does not surprise that the ossicles are among the most rarely found bones in the mammalian fossil record including the one of human ancestors. Given their important role in audition this lack of knowledge has ever been frustrating for researchers interested in studying hearing capacities of extinct species.

Tiny bones still present

This also applies to our closest extinct relatives - the Neandertals whose communicative capacities including existence of human spoken language is a major scientific debate ever since the first discovery of Neandertal remains. A research team led by Alexander Stoessel from the Max Planck Institute for Evolutionary Anthropology in Leipzig used high-resolution computer tomography scans of Neandertal skulls and systematically checked for ossicles that potentially became trapped within the cavity of the middle ear.

And indeed, the researchers found ear ossicles in 14 Neandertal individuals coming from sites in France, Germany, Croatia and Israel, resulting in the largest sample of ear ossicles of any fossil human species. “We were really astonished how often the ear ossicles are actually present in these fossil remains, particularly when the ear became filled with sediments” says lead researcher Alexander Stoessel.

After virtually reconstructing the bones, the team - which also included scientist from the Friedrich-Schiller University in Jena and the University College in London – compared them to ossicles of anatomically modern humans and also chimpanzees and gorillas which are our closest living relatives.

Since ossicles are not only small but also complex-shaped the researchers compared them by means of three-dimensional analysis that uses a much larger number of measuring points allowing for examination of the three-dimensional shape of a structure. “Despite the close relationship between anatomically modern humans and Neandertals to our surprise the ear ossicles are very differently shaped between the two human species” says Romain David who was involved in the study.

Based on the results of the morphological comparison the research team examined the potential reasons for these different morphologies. In order to see if these differences may affect hearing capacity of Neandertals and modern humans or reflects a tight relationship with the base of the skull they also analyzed the structures surrounding the ear ossicles. The outcome of this analysis was surprising, again since the functional parameters of the Neandertal and modern human middle ear are largely similar despite contrasting morphologies.

Similar communication skills in archaic humans

Instead, the team found the ear ossicles strongly related to the morphology of the surrounding cranial structures which also differ between the two human groups. The reseachers attribute these differences to different evolutionary trajectories that Neandertals and modern humans pursued in order to increase their brain volume which also impacted the structures of the cranial base which the middle ear is a part of.

“For us these results could be indicative for consistent aspects of vocal communication in anatomically modern humans and Neandertals that were already present in their common ancestor” says Jean-Jacques Hublin who is an author of this study and continues “these findings should be a basis for continuing research on the nature of the spoken language in archaic hominins”.

The findings are published in >Proceedings of the National Academy of Sciences.

Source: Max Planck Institute for Evolutionary Anthropology [September 27, 2016]

The Sima de los Huesos (SH) site has provided the largest collection of hominin crania in the fossil record, offering an unprecedented opportunity to perform a complete forensic taphonomic study on a population from the Middle Pleistocene.

The fractures found in seventeen crania from SH display a postmortem fracturation pattern, which occurred in the dry bone stage and is compatible with collective burial assemblages.

Nevertheless, in addition to the postmortem fractures, eight crania also display some typical perimortem traumas.

By using CT images we analyzed these fractures in detail. Interpersonal violence as a cause for the perimortem fractures can be confirmed for one of the skulls, Cranium 17 and also probable for Cranium 5 and Cranium 11.

For the rest of the crania, although other causes cannot be absolutely ruled out, the violence-related traumas are the most plausible scenario for the perimortem fractures.

If this hypothesis is confirmed, the team may be able to interpret that interpersonal violence was a recurrent behaviour in this population from the Middle Pleistocene.

The study is published in the >Journal of Archaeological Science.

Source: University College London [June 17, 2016]

On the outskirts of Beijing, a small limestone mountain named Dragon Bone Hill rises above the surrounding sprawl. Along the northern side, a path leads up to some fenced-off caves that draw 150,000 visitors each year, from schoolchildren to grey-haired pensioners. It was here, in 1929, that researchers discovered a nearly complete ancient skull that they determined was roughly half a million years old. Dubbed Peking Man, it was among the earliest human remains ever uncovered, and it helped to convince many researchers that humanity first evolved in Asia.

Since then, the central importance of Peking Man has faded. Although modern dating methods put the fossil even earlier—at up to 780,000 years old—the specimen has been eclipsed by discoveries in Africa that have yielded much older remains of ancient human relatives. Such finds have cemented Africa's status as the cradle of humanity—the place from which modern humans and their predecessors spread around the globe—and relegated Asia to a kind of evolutionary cul-de-sac.

But the tale of Peking Man has haunted generations of Chinese researchers, who have struggled to understand its relationship to modern humans. "It's a story without an ending," says Wu Xinzhi, a palaeontologist at the Chinese Academy of Sciences' Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) in Beijing. They wonder whether the descendants of Peking Man and fellow members of the species Homo erectus died out or evolved into a more modern species, and whether they contributed to the gene pool of China today.

Keen to get to the bottom of its people's ancestry, China has in the past decade stepped up its efforts to uncover evidence of early humans across the country. It is reanalysing old fossil finds and pouring tens of millions of dollars a year into excavations. And the government is setting up a US$1.1-million laboratory at the IVPP to extract and sequence ancient DNA.

The investment comes at a time when palaeoanthropologists across the globe are starting to pay more attention to Asian fossils and how they relate to other early hominins—creatures that are more closely related to humans than to chimps. Finds in China and other parts of Asia have made it clear that a dazzling variety of Homo species once roamed the continent. And they are challenging conventional ideas about the evolutionary history of humanity.

"Many Western scientists tend to see Asian fossils and artefacts through the prism of what was happening in Africa and Europe," says Wu. Those other continents have historically drawn more attention in studies of human evolution because of the antiquity of fossil finds there, and because they are closer to major palaeoanthropology research institutions, he says. "But it's increasingly clear that many Asian materials cannot fit into the traditional narrative of human evolution."

Chris Stringer, a palaeoanthropologist at the Natural History Museum in London, agrees. "Asia has been a forgotten continent," he says. "Its role in human evolution may have been largely under-appreciated."

Evolving story

In its typical form, the story of Homo sapiens starts in Africa. The exact details vary from one telling to another, but the key characters and events generally remain the same. And the title is always 'Out of Africa'.

In this standard view of human evolution, H. erectus first evolved there more than 2 million years ago. Then, some time before 600,000 years ago, it gave rise to a new species: Homo heidelbergensis, the oldest remains of which have been found in Ethiopia. About 400,000 years ago, some members of H. heidelbergensis left Africa and split into two branches: one ventured into the Middle East and Europe, where it evolved into Neanderthals; the other went east, where members became Denisovans—a group first discovered in Siberia in 2010. The remaining population of H. heidelbergensis in Africa eventually evolved into our own species, H. sapiens, about 200,000 years ago. Then these early humans expanded their range to Eurasia 60,000 years ago, where they replaced local hominins with a minuscule amount of interbreeding.

A hallmark of H. heidelbergensis—the potential common ancestor of Neanderthals, Denisovans and modern humans—is that individuals have a mixture of primitive and modern features. Like more archaic lineages, H. heidelbergensis has a massive brow ridge and no chin. But it also resembles H. sapiens, with its smaller teeth and bigger braincase. Most researchers have viewed H. heidelbergensis—or something similar—as a transitional form between H. erectus and H. sapiens.

Unfortunately, fossil evidence from this period, the dawn of the human race, is scarce and often ambiguous. It is the least understood episode in human evolution, says Russell Ciochon, a palaeoanthropologist at the University of Iowa in Iowa City. "But it's central to our understanding of humanity's ultimate origin."

The tale is further muddled by Chinese fossils analysed over the past four decades, which cast doubt over the linear progression from African H. erectus to modern humans. They show that, between roughly 900,000 and 125,000 years ago, east Asia was teeming with hominins endowed with features that would place them somewhere between H. erectus and H. sapiens, says Wu.

"Those fossils are a big mystery," says Ciochon. "They clearly represent more advanced species than H. erectus, but nobody knows what they are because they don't seem to fit into any categories we know."

The fossils' transitional characteristics have prompted researchers such as Stringer to lump them with H. heidelbergensis. Because the oldest of these forms, two skulls uncovered in Yunxian in Hubei province, date back 900,000 years >^{1, 2}>, Stringer even suggests that H. heidelbergensis might have originated in Asia and then spread to other continents.

But many researchers, including most Chinese palaeontologists, contend that the materials from China are different from European and African H. heidelbergensis fossils, despite some apparent similarities. One nearly complete skull unearthed at Dali in Shaanxi province and dated to 250,000 years ago, has a bigger braincase, a shorter face and a lower cheekbone than most H. heidelbergensis specimens>3, suggesting that the species was more advanced.

Such transitional forms persisted for hundreds of thousands of years in China, until species appeared with such modern traits that some researchers have classified them as H. sapiens. One of the most recent of these is represented by two teeth and a lower jawbone, dating to about 100,000 years ago, unearthed in 2007 by IVPP palaeoanthropologist Liu Wu and his colleagues>4. Discovered in Zhirendong, a cave in Guangxi province, the jaw has a classic modern-human appearance, but retains some archaic features of Peking Man, such as a more robust build and a less-protruding chin.

Most Chinese palaeontologists—and a few ardent supporters from the West—think that the transitional fossils are evidence that Peking Man was an ancestor of modern Asian people. In this model, known as multiregionalism or continuity with hybridization, hominins descended from H. erectus in Asia interbred with incoming groups from Africa and other parts of Eurasia, and their progeny gave rise to the ancestors of modern east Asians, says Wu.

Support for this idea also comes from artefacts in China. In Europe and Africa, stone tools changed markedly over time, but hominins in China used the same type of simple stone instruments from about 1.7 million years ago to 10,000 years ago. According to Gao Xing, an archaeologist at the IVPP, this suggests that local hominins evolved continuously, with little influence from outside populations.

Politics at play?

Some Western researchers suggest that there is a hint of nationalism in Chinese palaeontologists' support for continuity. "The Chinese—they do not accept the idea that H. sapiens evolved in Africa," says one researcher. "They want everything to come from China."

Chinese researchers reject such allegations. "This has nothing to do with nationalism," says Wu. It's all about the evidence—the transitional fossils and archaeological artefacts, he says. "Everything points to continuous evolution in China from H. erectus to modern human."

But the continuity-with-hybridization model is countered by overwhelming genetic data that point to Africa as the wellspring of modern humans. Studies of Chinese populations show that 97.4% of their genetic make-up is from ancestral modern humans from Africa, with the rest coming from extinct forms such as Neanderthals and Denisovans>5. "If there had been significant contributions from Chinese H. erectus, they would show up in the genetic data," says Li Hui, a population geneticist at Fudan University in Shanghai. Wu counters that the genetic contribution from archaic hominins in China could have been missed because no DNA has yet been recovered from them.

Many researchers say that there are ways to explain the existing Asian fossils without resorting to continuity with hybridization. The Zhirendong hominins, for instance, could represent an exodus of early modern humans from Africa between 120,000 and 80,000 years ago. Instead of remaining in the Levant in the Middle East, as was thought previously, these people could have expanded into east Asia, says Michael Petraglia, an archaeologist at the University of Oxford, UK.

Other evidence backs up this hypothesis: excavations at a cave in Daoxian in China's Hunan province have yielded 47 fossil teeth so modern-looking that they could have come from the mouths of people today. But the fossils are at least 80,000 years old, and perhaps 120,000 years old, Liu and his colleagues reported last year>6. "Those early migrants may have interbred with archaic populations along the way or in Asia, which could explain Zhirendong people's primitive traits," says Petraglia.

Another possibility is that some of the Chinese fossils, including the Dali skull, represent the mysterious Denisovans, a species identified from Siberian fossils that are more than 40,000 years old. Palaeontologists don't know what the Denisovans looked like, but studies of DNA recovered from their teeth and bones indicate that this ancient population contributed to the genomes of modern humans, especially Australian Aborigines, Papua New Guineans and Polynesians—suggesting that Denisovans might have roamed Asia.

Maria Martinon-Torres, a palaeoanthropologist at University College London, is among those who proposed that some of the Chinese hominins were Denisovans. She worked with IVPP researchers on an analysis>7, published last year, of a fossil assemblage uncovered at Xujiayao in Hebei province—including partial jaws and nine teeth dated to 125,000–100,000 years ago. The molar teeth are massive, with very robust roots and complex grooves, reminiscent of those from Denisovans, she says.

A third idea is even more radical. It emerged when Martinon-Torres and her colleagues compared more than 5,000 fossil teeth from around the world: the team found that Eurasian specimens are more similar to each other than to African ones>8. That work and more recent interpretations of fossil skulls suggest that Eurasian hominins evolved separately from African ones for a long stretch of time. The researchers propose that the first hominins that left Africa 1.8 million years ago were the eventual source of modern humans. Their descendants mostly settled in the Middle East, where the climate was favourable, and then produced waves of transitional hominins that spread elsewhere. One Eurasian group went to Indonesia, another gave rise to Neanderthals and Denisovans, and a third ventured back into Africa and evolved into H. sapiens, which later spread throughout the world. In this model, modern humans evolved in Africa, but their immediate ancestor originated in the Middle East.

Not everybody is convinced. "Fossil interpretations are notoriously problematic," says Svante Paabo, a palaeogeneticist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. But DNA from Eurasian fossils dating to the start of the human race could help to reveal which story—or combination—is correct. China is now making a push in that direction. Qiaomei Fu, a palaeogeneticist who did her PhD with Paabo, returned home last year to establish a lab to extract and sequence ancient DNA at the IVPP. One of her immediate goals is to see whether some of the Chinese fossils belong to the mysterious Denisovan group. The prominent molar teeth from Xujiayao will be an early target. "I think we have a prime suspect here," she says.

Fuzzy picture

Despite the different interpretations of the Chinese fossil record, everybody agrees that the evolutionary tale in Asia is much more interesting than people appreciated before. But the details remain fuzzy, because so few researchers have excavated in Asia.

When they have, the results have been startling. In 2003, a dig on Flores island in Indonesia turned up a diminutive hominin>9, which researchers named Homo floresiensis and dubbed the hobbit. With its odd assortment of features, the creature still provokes debate about whether it is a dwarfed form of H. erectus or some more primitive lineage that made it all the way from Africa to southeast Asia and lived until as recently as 60,000 years ago. Last month, more surprises emerged from Flores, where researchers found the remains of a hobbit-like hominin in rocks about 700,000 years old>10.

Recovering more fossils from all parts of Asia will clearly help to fill in the gaps. Many palaeoanthropologists also call for better access to existing materials. Most Chinese fossils—including some of the finest specimens, such as the Yunxian and Dali skulls—are accessible only to a handful of Chinese palaeontologists and their collaborators. "To make them available for general studies, with replicas or CT scans, would be fantastic," says Stringer. Moreover, fossil sites should be dated much more rigorously, preferably by multiple methods, researchers say.

But all agree that Asia—the largest continent on Earth—has a lot more to offer in terms of unravelling the human story. "The centre of gravity," says Petraglia, "is shifting eastward."

Author: Jane Qiu | Source: Nature 535, 22–25 (14 July 2016) doi:10.1038/535218a [July 15, 2016]

In a remarkable technical feat, researchers have sequenced DNA from fossils in Spain that are about 300,000 to 400,000 years old and have found an ancestor—or close relative—of Neanderthals. The nuclear DNA, which is the oldest ever sequenced from a member of the human family, may push back the date for the origins of the distinct ancestors of Neanderthals and modern humans, according to a presentation here yesterday at the fifth annual meeting of the European Society for the study of human evolution.

Ever since researchers first discovered thousands of bones and teeth from 28 individuals in the mid-1990s from Sima de los Huesos (“pit of bones”), a cave in the Atapuerca Mountains of Spain, they had noted that the fossils looked a lot like primitive Neanderthals. The Sima people, who lived before Neanderthals, were thought to have emerged in Europe. Yet their teeth, jaws, and large nasal cavities were among the traits that closely resembled those of Neanderthals, according to a team led by paleontologist Juan-Luis Arsuaga of the Complutense University of Madrid. As a result, his team classified the fossils as members of Homo heidelbergensis, a species that lived about 600,000 to 250,000 years ago in Europe, Africa, and Asia. Many researchers have thought H. heidelbergensis gave rise to Neanderthals and perhaps also to our species, H. sapiens, in the past 400,000 years or so.

But in 2013, the Sima fossils’ identity suddenly became complicated when a study of the maternally inherited mitochondrial DNA (mtDNA) from one of the bones revealed that it did not resemble that of a Neanderthal. Instead, it more closely matched the mtDNA of a Denisovan, an elusive type of extinct human discovered when its DNA was sequenced from a finger bone from Denisova Cave in Siberia. That finding was puzzling, prompting researchers to speculate that perhaps the Sima fossils had interbred with very early Denisovans or that the “Denisovan” mtDNA was the signature of an even more ancient hominin lineage, such as H. erectus. At the time, researchers at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, who had obtained the mtDNA announced that they would try to sequence the nuclear DNA of the fossils to solve the mystery.

After 2 years of intense effort, paleogeneticist Matthias Meyer of the Max Planck Institute for Evolutionary Anthropology has finally sequenced enough nuclear DNA from fossils of a tooth and a leg bone from the pit to solve the mystery. The task was especially challenging because the ancient DNA was degraded to short fragments, made up of as few as 25 to 40 single nucleotides. (Nucleotides—also known as base pairs—are the building blocks of DNA.) Although he and his colleagues did not sequence the entire genomes of the fossils, Meyer reported at the meeting that they did get 1 million to 2 million base pairs of ancient nuclear DNA.

They scanned this DNA for unique markers found only in Neanderthals or Denisovans or modern humans, and found that the two Sima fossils shared far more alleles—different nucleotides at the same address in the genome—with Neanderthals than Denisovans or modern humans. “Indeed, the Sima de los Huesos specimens are early Neanderthals or related to early Neanderthals,” suggesting that the split of Denisovans and Neanderthals should be moved back in time, Meyer reported at the meeting.

Researchers at the meeting were impressed by this new breakthrough in ancient DNA research. “This has been the next frontier with ancient DNA,” says evolutionary biologist Greger Larson of the University of Oxford in the United Kingdom.

The close affinity with Neanderthals, but not with Denisovans or modern humans, suggests that the lineage leading to Neanderthals was separate from other archaic humans earlier than most researchers have thought. That means that the ancestors of modern humans also had to split earlier than expected from the population that gave rise to Neanderthals and Denisovans, who were more closely related to each other than they were to modern humans. (Although all three groups interbred at low levels after their evolutionary paths diverged—and such interbreeding may have been the source of the Denisovan mtDNA in the first Sima fossil whose DNA was sequenced.) Indeed, Meyer suggested in his talk that the ancestors of H. sapiens may have diverged from the branch leading to Neanderthals and Denisovans as early as 550,000 to 765,000 years ago, although those results depend on different mutation rates in humans and are still unpublished.

That would mean that the ancestors of humans were already wandering down a solitary path apart from the other kinds of archaic humans on the planet 100,000 to 400,000 years earlier than expected. “It resolves one controversy—that they’re in the Neanderthal clade,” says paleoanthropologist Chris Stringer of the Natural History Museum in London. “But it’s not all good news: From my point of view, it pushes back the origin of H. sapiens from the Neanderthals and Denisovans.” The possibility that humans were a distinct group so early shakes up the human family tree, promising to lead to new debate about when and where the branches belong.

Author: Ann Gibbons | Source: ScienceMag/AAAS [September 11, 2015]

Archaeologists have uncovered a stone grinding tool in southern Italy which shows signs it was used to make flour that was boiled into gruel or baked into bread.

The discovery, which predates the dawn of farming, suggests that stone age man's first cultivated meal may have been a bowl of porridge made from grains growing wild and is the earliest known instance of human consumption of oats.

The find was made by a team led by Marta Mariotti Lippi at the University of Florence in Italy who made analysed starch grains found on the artefact.

They found evidence that the stone's creators also heated the grains before grinding them, perhaps to dry them out in the colder climate of the time and make the grain easier to grind and longer-lasting.

This multi-stage process would have been time consuming, but beneficial, while turning it into flour would have been a good way to transport it, which was important for Palaeolithic nomads.

Evidence of porridge consumption in Scotland dates back to 4,000 BC, when oats and other grains began to be cultivated by the first farmers.

Mariotti Lippi’s team hopes to continue studying ancient grinding stones to find out more about the stone age plant diet.

The stone was found in the Grotta Paglicci, Apulia, which was home to stone age hunter gatherers between 34,000 and 32,000 years ago and contains mural paintings, depicting horses and handprints. Images of goats, cows, a serpent, a nest with eggs, and a hunting scene have also been found engraved on bone.

Archaeologist Matt Pope, of University College London, said that the find shed light on the diet of early humans and the spread of food cultivation.

He said: “There is a relationship there to be explored between diet, experimentation with processing plant food and cultural sophistication.

“We’ve had evidence of the processing of roots and cattails, but here we’ve got a grain, and a grain that we’re very familiar with.

“If we were to look more systematically for ground stone technology we would find this is a more widespread phenomenon.”

The study is published in Proceedings of the National Academy of Sciences.

Author: Jody Harrison | Source: Herald Scotland [September 08, 2015]