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UNIVERSITY OF BRISTOL—A team at the University of Bristol has developed a new method of dating pottery which is allowing archaeologists to date prehistoric finds from across the world with remarkable accuracy.

The exciting new method, reported in detail* today in the journal Nature, is now being used to date pottery from a range of key sites up to 8,000 years old in Britain, Europe and Africa.

Pottery and the dating game

Archaeological pottery has been used to date archaeological sites for more than a century, and from the Roman period onwards can offer quite precise dating. But further back in time, for example at the prehistoric sites of the earliest Neolithic farmers, accurate dating becomes more difficult because the kinds of pottery are often less distinctive and there are no coins or historical records to give context.

This is where radiocarbon dating, also known as 14C-dating, comes to the rescue. Until now, archaeologists had to radiocarbon date bones or other organic materials buried with the pots to understand their age.

But the best and most accurate way to date pots would be to date them directly, which the University of Bristol team has now introduced by dating the fatty acids left behind from food preparation.

Professor Richard Evershed from the University of Bristol’s School of Chemistry led the team. He said: “Being able to directly date archaeological pots is one of the “Holy Grails” of archaeology. This new method is based on an idea I had going back more than 20 years and it is now allowing the community to better understand key archaeological sites across the world.

“We made several earlier attempts to get the method right, but it wasn’t until we established our own radiocarbon facility in Bristol that we cracked it. There’s a particular beauty in the way these new technologies came together to make this important work possible and now archaeological questions that are currently very difficult to resolve could be answered.”

How the method works

The trick was isolating individual fat compounds from food residues, perhaps left by cooking meat or milk, protected within the pores of prehistoric cooking pots. The team brought together the latest high resolution nuclear magnetic resonance spectroscopy and mass spectrometry technologies to design a new way of isolating the fatty acids and checking they were pure enough for accurate dating.

The team then had to show that the new approach gave dates as accurate as those given by materials commonly dated in archaeology, such as bones, seeds and wood. To do this the team looked at fat extracts from ancient pottery at a range of key sites in Britain, Europe and Africa with already precise dating which were up to 8,000 years old.

From the famous Sweet Track site in Somerset and several sites in the Alsace region of France, to the World Heritage site of Çatalhöyük in central Turkey and the famous rock shelter site of Takarkori in Saharan Africa, the new method was proven to date sites incredibly accurately, even to within a human life span.

Professor Alex Bayliss, Head of Scientific Dating at Historic England, who undertook the statistical analyses, added: “It is very difficult to overstate the importance of this advance to the archaeological community. Pottery typology is the most widely used dating technique in the discipline, and so the opportunity to place different kinds of pottery in calendar time much more securely will be of great practical significance.”

Using the pottery calendar to better understand London’s pre-history

In London, England, the new dating method has been used on a remarkable collection of pottery found in Shoreditch, thought to be the most significant group of Early Neolithic pottery ever found in the capital. The extraordinary trove, comprising 436 fragments from at least 24 separate vessels weighing nearly 6.5 kilos in total, was discovered by archaeologists from MOLA (Museum of London Archaeology).

The site appeared to date from the time when the first farmers came to Britain but accurately dating it was difficult until the Bristol team, using their new dating method on traces of milk fats extracted from the pots, showed the pottery was 5,500 years old. The team were able to date the pottery collection to a window of just 138 years, to around 3600BC.

The results indicate that around 5600 years ago the area around what is now Shoreditch High Street was used by established farmers who ate cow, sheep or goat dairy products as a central part of their diet. These people were likely to have been linked to the migrant groups who were the first to introduce farming to Britain from Continental Europe around 4000 BC – just 400 years earlier.

Jon Cotton, a consultant prehistorian working for MOLA, said: “This remarkable collection helps to fill a critical gap in London’s prehistory. Archaeological evidence for the period after farming arrived in Britain rarely survives in the capital, let alone still in-situ. This is the strongest evidence yet that people in the area later occupied by the city and its immediate hinterland were living a less mobile, farming-based lifestyle during the Early Neolithic period.”

The results from this site are a prime example of where pottery survives in circumstances that other organic materials do not, so using this revolutionary new method will unlock important information about our prehistoric past.

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Using radiocarbon dating to date fat compounds within the pores of pottery provides revolutionary, accurate method of dating. Bluebudgie, Pixabay, Public Domain

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*’Accurate compound-specific 14C dating of archaeological pottery vessels’ by R. Evershed, E. Casanova, T. Knowles, A. Bayliss, J. Dunne, M. Baranski et al in Nature

Article Source: UNIVERSITY OF BRISTOL news release

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UNIVERSITY OF SOUTHAMPTON—Research led by scientists at the University of Southampton has found settlers arrived in East Polynesia around 200 years earlier than previously thought.

Colonization of the vast eastern Pacific with its few and far-flung island archipelagos was a remarkable achievement in human history. Yet the timing, character, and drivers of this accomplishment remain poorly understood.

However, this new study has found a major change in the climate of the region, which resulted in a dry period, coinciding with the arrival of people on the tiny island of Atiu, in the southern group of the Cook Islands, around 900AD.

Findings are published in the paper, ‘Human settlement of East Polynesia earlier, incremental and coincident with prolonged South Pacific drought’ in the journal PNAS.

“The ancestors of the Polynesians, the Lapita people, migrated east into the Pacific Ocean as far as Fiji, Tonga and Samoa, reaching them around 2800 years ago. But for almost 1500 years humans failed to migrate any further into the pacific,” explains lead researcher, Professor David Sear of the University of Southampton. “Our research gives us a much more accurate timescale of when people first arrived in the region and helps answer some key questions about why they made their hazardous journey east.”

A team of geographers, archaeologists and geochemists from the UK, New Zealand and the US, worked with the people of Atiu, to collect core samples of lake mud, charting over 6000 years of history. Back in the labs in UK and US, the mud samples were subjected to a range of analyses including new techniques for reconstructing precipitation, and detecting the presence of mammalian faeces.

Apart from fruit bats, the Southern Cook Islands never had mammal populations before humans settled there, so when the researchers found evidence of mammal faeces alongside other evidence for landscape disturbance and burning, it was a clear sign of the arrival of people. Within 100 years the first settlers, most likely from Tonga or Samoa, changed the landscape by burning native forest to make way for crops.

The team, including undergraduate and postgraduate students from the universities of Southampton and Washington, as well as scientists from Newcastle, Liverpool and Auckland universities, also examined lake sediments from Samoa and Vanuatu. Using this data, they found evidence for a major climate change which coincided with the newly established arrival time of the settlers.

The data revealed a major change in the climate of the South Pacific region with the main rainbands that bring water to the archipelagos of Vanuatu, Samoa, Tonga and Fiji migrating north. The result was the driest period in the last 2000 years.

This led the researchers to conclude that, alongside growing populations, water stress drove decisions to make dangerous voyages, aided by changes in winds that enabled easterly sailing. Soon after the arrival of people to Atiu, the climate changed again. Rain returned to the eastern Pacific – supporting a rapid (c. 200 years) settlement of the remaining islands of Polynesia.

Professor Sear adds: “Today, changing climate is again putting pressures on Pacific island communities, only this time the option to migrate is not so simple. Within two centuries of first arrival those first settlers changed the landscape and the ecology, but were able to make a home. Pacific islanders now live with modified ecologies, permanent national boundaries and islands already occupied by people. The ability to migrate in response to changing climate is no longer the option it once was.”

This research was supported by grants from the NERC, Explorers Club and Royal Geographical Society. The team wishes to acknowledge the support of the peoples of the Cook Islands, Samoa and Vanuatu.

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Lake Te Roto on Atiu where evidence was found of the arrival of early humans. University of Southampton

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Two halves of core sample taken from Lake Te Roto on Atiu. University of Southampton

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Article Source: UNIVERSITY OF SOUTHAMPTON news release

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UNIVERSITY OF JOHANNESBURG—An unusual skullcap and thousands of clues have created a southern twist to the story of human ancestors, in research published in Science on 3 April.

The rolling hills northwest of Johannesburg are famous for fossils of human-like creatures called hominins. Because of this, the area is known as the Cradle of Humankind.

“During our field school excavations at Drimolen, a student began uncovering a cluster of fragments. We could see that they were parts of a skull. But they weren’t immediately identifiable,” says Ms Stephanie Baker.

Baker is a researcher and PhD candidate at the Palaeo-Research Institute at the University of Johannesburg. She manages research at the Drimolen fossil site in the Cradle of Humankind where the fragments of DNH 134 were found.

The international team was led by researchers from La Trobe University in Australia and Washington University in St. Louis in the United States.

Fossil forensics

Fossils that are millions of years old often come out of the soil in fragments. The fragments need to be rebuilt before researchers can confidently identify what kind of animal they came from.

“Over the course of the field season more and more fragments were uncovered. We began piecing them together. No one could decide what this skullcap was from, until one night it all came together – and we realised we were looking at a hominin!” she says. They named the skullcap DNH 134.

The next question was – what kind of hominin? The Cradle of Humankind has several different species of human ancestors and the Drimolen site had at least two kinds.

“This find really challenged us. We compared the assembled skullcap to all of the other examples of hominins in the Cradle area. Eventually, its teardrop shape and relatively big brain cavity meant we were looking at Homo erectus,” says Baker.

Homo erectus is one of our direct human ancestors and is best known for migrating out of Africa into the rest of the world.

These hominins walked upright and were a more human-like species than the other hominins found in the Cradle. They had shorter arms and longer legs. They could walk and run for longer distances over the African grasslands than the others.

How old?

Once the question of ‘which species?’ was answered, two other huge questions presented themselves. How long ago was this individual alive? And how old were they when they died?

The researchers knew that no other Homo erectus fossils had ever been found in South Africa before. Even more surprising was the time period suggested by the soil layers the skull fragments were found in. “Before we found DNH 134, we knew that the oldest Homo erectus in the world was from Dmanisi in Georgia dating to 1.8 million years ago,” says Baker.

Building a 3D puzzle over time

Trying to figure out how old fossils are from the caves west of Johannesburg is quite tricky. There were no volcanoes during the time of the hominins, so there are no ash layers to give the researchers quick age estimates, like they use for eastern African sites.

But while they were uncovering the fragments at Drimolen, they kept and recorded every clue they could find. This included fragments of small animals like bats and lizards, but also things like soil samples.

They can also tell exactly where in 3D-space in the Drimolen quarry each little fossil fragment was found.

Then the research team used every possible dating technique available to get the most accurate possible date for the deposit. This included Palaeomagnetic dating, Electron spin resonance, Uranium lead dating, and faunal dating.

Possible shifted, earlier origin

“We collated all of the dates from each of these techniques and together they showed that we had a very precise age. We now know that the Drimolen Main Quarry and all of the fossils in it, are dated from 2.04 to 1.95 million years ago,” says Baker.

That means that DNH 134 is much older than the next oldest Homo erectus in Africa; and from Georgia.

“The age of the DNH 134 fossil shows that Homo erectus existed 150,000 to 200,000 years earlier than previously thought,” says Professor Andy Herries. Herries is the project co-director with Ms Baker and lead researcher. He is Head of the Department of Archaeology and History, at La Trobe University in Australia and an associate in the Palaeo-Research Institute at UJ.

Because Homo erectus is one of our direct ancestors, the discovery has implications for the origins of modern humans.

“Until this find, we always assumed Homo erectus originated from eastern Africa. But DNH 134 shows that Homo erectus, one of our direct ancestors, possibly comes from southern Africa instead. That would mean that they later moved northwards into East Africa. From there they went through North Africa to populate the rest of the world,” says Baker.

The skull is also unusual because it is the skull of a young Homo erectus.

“The Homo erectus skull we found, was likely aged between two and three years old when it died,” says Herries.

Sharing a landscape

The age of the DNH 134 skullcap shows something else – that three species of early human ancestor lived in southern Africa at the same time at the Drimolen fossil site.

“We can now say Homo erectus shared the landscape with two other types of humans in South Africa, Paranthropus and Australopithecus,” says Herries.

This might mean they needed to use different parts of the landscape to avoid competing with one another. For a start, they looked different.

Paranthropus robustus hominins were shorter than Homo erectus and Australopithecus, says Baker.

“Paranthropus robustus ate things like roots and tubers, which is why their teeth are really big. They used their enormous teeth for grinding down what we call fall-back foods – tough hard plants.”

Changing weather

In comparison to the other two species, Homo erectus hominins were tall and slender. They ate things which are easier to digest, like fruits and berries.

“We also know that they were eating meat, but we aren’t exactly sure how they were getting it yet. We can say that at least these early Homo erectus weren’t hunting with any weaponry yet,” says Baker.

“We also know that they were able to cover long distances. Which turned out lucky for them, because during their time, the climate changed in southern Africa.

Paranthropus and Australopithecus evolved in warm and humid climates and were used to that. But then the weather began to shift from warm and humid, to cool and dry,” she says.

Gradually the tree-cover diminished, and grasses took their place. Eventually the forests were replaced with the African savannah grasslands of today. The cooler weather suited the more mobile and social Homo erectus better. But it meant that Paranthropus had to rely on less desirable foods.

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A Homo erectus (DNH 134) fossil find at Drimolen palaeocave system northwest of Johannesburg in South Africa. The skullcap has been identified as the oldest to date for Homo erectus, based on research published in Science. The hominin is a direct ancestor of modern humans, experienced a changing climate, and moved out of Africa into other continents. The discovery of DNH 134 pushes the possible origin of Homo erectus back between 150,000 and 200,000 years. Therese van Wyk, University of Johannesburg.

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The skull of an African Homo erectus woman at the Natural History Museum in London, England. Emőke Dénes, Wikimedia Commons, Creative Commons Attribution-Share Alike 4.0 International license.

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A model of the face of an adult female Homo erectus, one of the first truly human ancestors of modern humans, on display in the Hall of Human Origins in the Smithsonian Museum of Natural History in Washington, D.C. Reconstruction by John Gurche; photographed by Tim Evanson, Wikimedia Commons, Creative Commons Attribution-Share Alike 2.0 Generic license.

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Article Source: UNIVERSITY OF JOHANNESBURG news release

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Science—Nearly 2 million years ago, three hominin genera – Australopithecus, Paranthropus and the earliest Homo erectus lineage – lived as contemporaries in the karst landscape of what is now South Africa, according to a new geochronological evaluation of the hominin fossil-rich Drimolen Paleocave complex. Combined with other evidence, authors Andy Herries et al. argue that the site reflects a period of transition in southern Africa driven by climatic variability, one marked by endemic species, like Australopithecus, going extinct, while new migrants – Homo and Paranthropus – moved in. In their study, Herries and colleagues describe the geological context and age of two hominin crania fossils recently recovered from the Drimolen, representing Homo and Paranthropus. Using a combination of electron spin resonance, paleomagnetism and uranium-lead dating, Herries et al. pieced together the chronology of the Drimolen Main Quarry (DMQ). The results show that the Homo and Paranthropus fossils recovered from the region date to 2.04-1.95 million-years-old, which establishes both as the oldest definitive examples of their respective species (H. erectus and P. robustus). “If correct, Herries [et al.’s] results provide the most precisely dated remains in South Africa [and] add more than a hundred thousand years to the first appearance dates of at least H. erectus,” writes Susan Antón in a related Perspective. The crania ages also indicate that early Homo and Paranthropus hominins lived at the same time as their older Australopithecus cousins roughly 2 million years ago, which suggests a period of transition at the site; as endemic species, like Australopithecus, went extinct, new migrants – Homo and Paranthropus – moved in, the authors suggest. What’s more, the relative simplicity of the geological context of DMQ as revealed by the new geochronological techniques challenges the perceived complexity of other similarly aged South African paleocave sites, suggesting that much of what is known about the stratigraphy in these hominin-bearing sites may need to be reevaluated, according to the authors.

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La Trobe University PhD student Angeline Leece in front of fossil bearing brecccia at Drimolen. Jesse Martin

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The drimolen fossil site. Andy Herries

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The Drimolen excavations and excavated fossils. Andy Herries

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DNH 134 (Homo erectus) cranium, excavated from Drimolen, with stylized projection of the outline of the rest of the skull. Andy Herries, Jesse Martin and Renaud Joannes-Boyau

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Article Source: Science news release

This research appears in the 3 April 2020 issue of Science.

Science is published by AAAS, the nonprofit science society.

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UNIVERSITY OF PLYMOUTH—Neolithic populations have long been credited with bringing about a revolution in farming practices across Europe. However, a new study suggests it was not until the Bronze Age several millennia later that human activity led to significant changes to the continent’s landscape.

Scientists from the University of Copenhagen and the University of Plymouth led research tracing how the two major human migrations recorded in Holocene Europe – the northwestward movement of Anatolian farmer populations during the Neolithic and the westward movement of Yamnaya steppe peoples during the Bronze Age – unfolded.

In particular, they analyzed how they were associated with changes in vegetation – which led to Europe’s forests being replaced with the agricultural landscape still much in evidence today.

Their results, published in PNAS, show the two migrations differ markedly in both their spread and environmental implications, with the Yamnaya expansion moving quicker and resulting in greater vegetation changes than the earlier Neolithic farmer expansion.

The study – also involving the University of Gothenburg and the University of Cambridge – used techniques commonly applied in environmental science to model climate and pollution, and applied them to instead analyze human population movements in the last 10 millennia of European history.

It showed that a decline in broad-leaf forest and an increase in pasture and natural grassland vegetation was concurrent with a decline in hunter-gatherer ancestry, and may have been associated with the fast movement of steppe peoples during the Bronze Age.

It also demonstrated that natural variations in climate patterns during this period are associated with these land cover changes.

The research is the first to model the spread of ancestry in ancient genomes through time and space, and provides the first framework for comparing human migrations and land cover changes, while also accounting for changes in climate.

Dr Fernando Racimo, Assistant Professor at the University of Copenhagen and the study’s lead author, said: “The movement of steppe peoples that occurred in the Bronze Age had a particularly strong impact on European vegetation. As these peoples were moving westward, we see increases in the amount of pasture lands and decreases in broad leaf forests throughout the continent. We can now also compare movements of genes to the spread of cultural packages. In the case of the Neolithic farming revolution, for example, the two track each other particularly well, in both space and time.”

The research made use of land cover maps showing vegetation change over the past 11,000 years, which were produced through the University of Plymouth’s Deforesting Europe project.

Scientists working on that project have previously shown more than half of Europe’s forests have disappeared over the past 6,000 years due to increasing demand for agricultural land and the use of wood as a source of fuel.

Dr Jessie Woodbridge, Research Fellow at the University of Plymouth and co-author on the study, added: “European landscapes have been transformed drastically over thousands of years. Knowledge of how people interacted with their environment in the past has implications for understanding the way in which people use and impact upon the world today. Collaboration with palaeo-geneticists has allowed the migration of human populations in the past to be tracked using ancient DNA, and for the first time allowed us to assess the impact of different farming populations on land-cover change, which provides new insights into past human-environment interactions.”

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A graphic depicting the spread of Yamnaya ancestry over time over a period of around 8,000 years. Fernando Racimo

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Article Source: UNIVERSITY OF PLYMOUTH news release

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UNIVERSITY AT BUFFALO—BUFFALO, N.Y.—In recent years, scientists have uncovered evidence that modern humans and Neanderthals share a tangled past. In the course of human history, these two species of hominins interbred not just once, but at multiple times, the thinking goes.

A new study supports this notion, finding that people in Eurasia today have genetic material linked to Neanderthals from the Altai mountains in modern-day Siberia. This is noteworthy because past research has shown that Neanderthals connected to a different, distant location — the Vindija Cave in modern-day Croatia — have also contributed DNA to modern-day Eurasian populations.

The results reinforce the concept that Neanderthal DNA has been woven into the modern human genome on multiple occasions as our ancestors met Neanderthals time and again in different parts of the world.

The study was published on March 31 in the journal Genetics.

“It’s not a single introgression of genetic material from Neanderthals,” says lead researcher Omer Gokcumen, a University at Buffalo biologist. “It’s just this spider web of interactions that happen over and over again, where different ancient hominins are interacting with each other, and our paper is adding to this picture. This project will now add to an emerging chorus — we’ve been looking into this phenomenon for a couple of years, and there are a couple of papers that came out recently that deal with similar concepts.”

“The picture in my mind now is we have all these archaic hominin populations in Europe, in Asia, in Siberia, in Africa. For one reason or another, the ancestors of modern humans in Africa start expanding in population, and as they expand their range, they meet with these other hominins and absorb their DNA, if you will,” Gokcumen says. “We probably met different Neanderthal populations at different times in our expansion into other parts of the globe.”

Gokcumen, associate professor of biological sciences in the UB College of Arts and Sciences, led the study with first author Recep Ozgur Taskent, a recent UB PhD graduate in the department. Co-authors include UB PhD graduate Yen Lung Lin, now a postdoctoral scholar at the University of Chicago; and Ioannis Patramanis and Pavlos Pavlidis, PhD, of the Foundation for Research and Technology in Greece.

The research was funded by the U.S. National Science Foundation.

To complete the project, scientists analyzed the DNA of hundreds of people of Eurasian ancestry. The goal was to hunt for fragments of genetic material that may have been inherited from Neanderthals.

This research found that the Eurasian populations studied could trace some genetic material back to two different Neanderthal lineages: one represented by a Neanderthal whose remains were discovered in the Vindija cave in Croatia, and another represented by a Neanderthal whose remains were discovered in the Altai mountains in Russia.

Scientists also discovered that the modern-day populations they studied also share genetic deletions — areas of DNA that are missing — with both the Vindija and Altai Neanderthal lineages.

The DNA of the Vindija and Altai Neanderthals, along with the modern human populations studied, were previously sequenced by different research teams.

“It seems like the story of human evolution is not so much like at tree with branches that just grow in different directions. It turns out that the branches have all these connections between them,” Gokcumen says. “We are figuring out these connections, which is really exciting. The story is not as neat as it was before. Every single ancient genome that is sequenced seems to create a completely new perspective in our understanding of human evolution, and every new genome that’s sequenced in the future may completely change the story again.”

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Neanderthals and modern humans interbred in multiple locations as modern humans migrated across the landscape. Pixabay Public Domain Image

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Article Source: UNIVERSITY AT BUFFALO news release

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ARIZONA STATE UNIVERSITY—Scientists have long been able to measure and analyze the fossil skulls of our ancient ancestors to estimate brain volume and growth. The question of how these ancient brains compare to modern human brains and the brains of our closest primate cousin, the chimpanzee, continues to be a major target of investigation.

A new study published in Science Advances used CT-scanning technology to view three-million-year old brain imprints inside fossil skulls of the species Australopithecus afarensis (famous for “Lucy” and “Selam” from Ethiopia’s Afar region) to shed new light on the evolution of brain organization and growth. The research reveals that while Lucy’s species had an ape-like brain structure, the brain took longer to reach adult size, suggesting that infants may have had a longer dependence on caregivers, a human-like trait.

The CT-scanning enabled the researchers to get at two long-standing questions that could not be answered by visual observation and measurement alone: Is there evidence for human-like brain reorganization in Australopithecus afarensis, and was the pattern of brain growth in this species more similar to that of chimpanzees or that of humans?

To study brain growth and organization in A. afarensis, the researchers, including ASU paleoanthropologist William Kimbel, scanned eight fossil crania from the Ethiopian sites of Dikika and Hadar using high-resolution conventional and synchrotron-computed tomography. Kimbel, leader of the field work at Hadar, is director of the Institute of Human Origins and Virginia M. Ullman Professor of Natural History and the Environment in the School of Human Evolution and Social Change.

Lucy’s species inhabited eastern Africa more than three million years ago–“Lucy” herself is estimated to be 3.2 million years old–and occupies a key position in the hominin family tree, as it is widely accepted to be ancestral to all later hominins, including the lineage leading to modern humans.

“Lucy and her kin provide important evidence about early hominin behavior–they walked upright, had brains that were around 20 percent larger than those of chimpanzees, and may have used sharp stone tools,” explains coauthor Zeresenay Alemseged (University of Chicago), who directs the Dikika field project in Ethiopia and is an International Research Affiliate with the Institute of Human Origins.

Brains do not fossilize, but as the brain grows and expands before and after birth, the tissues surrounding its outer layer leave an imprint on the inside of the bony braincase. The brains of modern humans are not only much larger than those of our closest living ape relatives but are also organized differently and take longer to grow and mature. Compared with chimpanzees, modern human infants learn longer and are entirely dependent on parental care for longer periods of time. Together, these characteristics are important for human cognition and social behavior, but their evolutionary origins remain unclear.

The CT scans resulted in high-resolution digital “endocasts” of the interior of the skulls, where the anatomical structure of the brains could be visualized and analyzed. Based on these endocasts, the researchers could measure brain volume and infer key aspects of cerebral organization from impressions of the brain’s structure.

A key difference between apes and humans involves the organization of the brain’s parietal lobe–important in the integration and processing of sensory information–and occipital lobe in the visual center at the rear of the brain. The exceptionally preserved endocast of “Selam,” a skull and associated skeleton of an Australopithecus afarensis infant found at Dikika in 2000, has an unambiguous impression of the lunate sulcus–a fissure in the occipital lobe marking the boundary of the visual area that is more prominent and located more forward in apes than in humans–in an ape-like position. The scan of the endocranial imprint of an adult A. afarensis fossil from Hadar (A.L. 162-28) reveals a previously undetected impression of the lunate sulcus, which is also in an ape-like position.

Some scientists had conjectured that human-like brain reorganization in australopiths was linked to behaviors that were more complex than those of their great ape relatives (e.g., stone-tool manufacture, mentalizing, and vocal communication). Unfortunately, the lunate sulcus typically does not reproduce well on endocasts, so there was unresolved controversy about its position in Australopithecus.

“A highlight of our work is how cutting-edge technology can clear up long-standing debates about these three million-year-old fossils,” notes coauthor Kimbel. “Our ability to ‘peer’ into the hidden details of bone and tooth structure with CT scans has truly revolutionized the science of our origins.”

A comparison of infant and adult endocranial volumes also indicates more human-like protracted brain growth in Australopithecus afarensis, likely critical for the evolution of a long period of childhood learning in hominins.

In infants, CT scans of the dentition make it possible to determine an individual’s age at death by counting dental growth lines. Similar to the growth rings of a tree, virtual sections of a tooth reveal incremental growth lines reflecting the body’s internal rhythm. Studying the fossilized teeth of the Dikika infant, the team’s dental experts calculated an age at death of 2.4 years.

The pace of dental development of the Dikika infant was broadly comparable to that of chimpanzees and therefore faster than in modern humans. But given that the brains of Australopithecus afarensis adults were roughly 20 percent larger than those of chimpanzees, the Dikika child’s small endocranial volume suggests a prolonged period of brain development relative to chimpanzees.

“The combination of apelike brain structure and humanlike protracted brain growth in Lucy’s species was unexpected,” says Kimbel. “That finding supports the idea that human brain evolution was very much a piecemeal affair, with extended brain growth appearing before the origin of our own genus, Homo.”

Among primates, different rates of growth and maturation are associated with different infant-care strategies, suggesting that the extended period of brain growth in Australopithecus afarensis may have been linked to a long dependence on caregivers. Alternatively, slow brain growth could also primarily represent a way to spread the energetic requirements of dependent offspring over many years in environments where food is not always abundant. In either case, protracted brain growth in Australopithecus afarensis provided the basis for subsequent evolution of the brain and social behavior in hominins and was likely critical for the evolution of a long period of childhood learning.

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Brain imprints in fossil skulls of the species Australopithecus afarensis (famous for “Lucy” and the “Dikika child” from Ethiopia pictured here) shed new light on the evolution of brain growth and organization. The exceptionally preserved endocranial imprint of the Dikika child reveals an ape-like brain organization, and no features derived towards humans. Philipp Gunz, MPI EVA Leipzig.

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Article Source: ARIZONA STATE UNIVERSITY news release

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UNIVERSITY OF COPENHAGEN THE FACULTY OF HEALTH AND MEDICAL SCIENCES—Genetic information from an 800,000-year-old human fossil has been retrieved for the first time. The results from the University of Copenhagen shed light on one of the branching points in the human family tree, reaching much further back in time than previously possible.

An important advancement in human evolution studies has been achieved after scientists retrieved the oldest human genetic data set from an 800,000-year-old tooth belonging to the hominin species Homo antecessor.

The findings by scientists from the University of Copenhagen (Denmark), in collaboration with colleagues from the CENIEH (National Research Center on Human Evolution) in Burgos, Spain, and other institutions, are published April 1st in Nature.

“Ancient protein analysis provides evidence for a close relationship between Homo antecessor, us (Homo sapiens), Neanderthals, and Denisovans. Our results support the idea that Homo antecessor was a sister group to the group containing Homo sapiens, Neanderthals, and Denisovans”, says Frido Welker, Postdoctoral Research Fellow at the Globe Institute, University of Copenhagen, and first author on the paper.

Reconstructing the human family tree

By using a technique called mass spectrometry, researchers sequenced ancient proteins from dental enamel, and confidently determined the position of Homo antecessor in the human family tree.

The new molecular method, palaeoproteomics, developed by researchers at the Faculty of Health and Medical Sciences, University of Copenhagen, enables scientists to retrieve molecular evidence to accurately reconstruct human evolution from further back in time than ever before.

The human and the chimpanzee lineages split from each other about 9-7 million years ago. Scientists have relentlessly aimed to better understand the evolutionary relations between our species and the others, all now extinct, in the human lineage.

“Much of what we know so far is based either on the results of ancient DNA analysis, or on observations of the shape and the physical structure of fossils. Because of the chemical degradation of DNA over time, the oldest human DNA retrieved so far is dated at no more than approximately 400.000 years”, says Enrico Cappellini, Associate Professor at the Globe Institute, University of Copenhagen, and leading author on the paper.

“Now, the analysis of ancient proteins with mass spectrometry, an approach commonly known as palaeoproteomics, allow us to overcome these limits”, he adds.

Theories on human evolution

The fossils analyzed by the researchers were found by palaeoanthropologist José María Bermúdez de Castro and his team in 1994 in stratigraphic level TD6 from the Gran Dolina cave site, one of the archaeological and paleontological sites of the Sierra de Atapuerca, Spain.

Initial observations led to conclude that Homo antecessor was the last common ancestor to modern humans and Neanderthals, a conclusion based on the physical shape and appearance of the fossils. In the following years, the exact relation between Homo antecessor and other human groups, like ourselves and Neanderthals, has been discussed intensely among anthropologists.

Although the hypothesis that Homo antecessor could be the common ancestor of Neanderthals and modern humans is very difficult to fit into the evolutionary scenario of the genus Homo, new findings in TD6 and subsequent studies revealed several characters shared among the human species found in Atapuerca and the Neanderthals. In addition, new studies confirmed that the facial features of Homo antecessor are very similar to those of Homo sapiens and very different from those of the Neanderthals and their more recent ancestors.

“I am happy that the protein study provides evidence that the Homo antecessor species may be closely related to the last common ancestor of Homo sapiens, Neanderthals, and Denisovans. The features shared by Homo antecessor with these hominins clearly appeared much earlier than previously thought. Homo antecessor would therefore be a basal species of the emerging humanity formed by Neanderthals, Denisovans, and modern humans”, adds José María Bermúdez de Castro, Scientific Co-director of the excavations in Atapuerca and co-corresponding author on the paper.

World class-expertise

Findings like these are made possible through an extensive collaboration between different research fields: from paleoanthropology to biochemistry, proteomics and population genomics.

Retrieval of ancient genetic material from the rarest fossil specimens requires top quality expertise and equipment. This is the reason behind the now ten-years-long strategic collaboration between Enrico Cappellini and Jesper Velgaard Olsen, Professor at the Novo Nordisk Foundation Center for Protein Research, University of Copenhagen and co-author on the paper.

“This study is an exciting milestone in palaeoproteomics. Using state of the art mass spectrometry, we determine the sequence of amino acids within protein remains from Homo antecessor dental enamel. We can then compare the ancient protein sequences we ‘read’ to those of other hominins, for example Neanderthals and Homo sapiens, to determine how they are genetically related”, says Jesper Velgaard Olsen.

“I really look forward to seeing what palaeoproteomics will reveal in the future”, concludes Enrico Cappellini.

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Homo antecessor, incomplete skull from “Gran Dolina” (ATD6-15 & ATD6-69), in Atapuerca, Spain. Locutus Borg, Wikimedia Commons

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Article Source: UNIVERSITY OF COPENHAGEN THE FACULTY OF HEALTH AND MEDICAL SCIENCES news release

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MASSACHUSETTS INSTITUTE OF TECHNOLOGY—When Spanish invaders arrived in the Americas, they were generally able to subjugate the local peoples thanks, in part, to their superior weaponry and technology. But archeological evidence indicates that, in at least one crucial respect, the Spaniards were quite dependent on an older indigenous technology in parts of Mesoamerica (today’s Mexico, Guatemala, Belize, and Honduras).

The invaders needed copper for their artillery, as well as for coins, kettles, and pans, but they lacked the knowledge and skills to produce the metal. Even Spain at that time had not produced the metal domestically for centuries, relying on imports from central Europe. In Mesoamerica they had to depend on local smelters, furnace builders, and miners to produce the essential material. Those skilled workers, in turn, were able to bargain for exemption from the taxes levied on the other indigenous people.

This dependence continued for at least a century, and perhaps as long as two centuries or more, according to new findings published in the journal Latin American Antiquity, in a paper by Dorothy Hosler, professor of archeology and ancient technology at MIT, and Johan Garcia Zaidua, a researcher at the University of Porto, in Portugal.

The research, at the site of El Manchón, in Mexico, made use of information gleaned from more than four centuries worth of archeological features and artifacts excavated by Hosler and her crew over multiple years of fieldwork, as well as from lab work and historical archives in Portugal, Spain, and Mexico analyzed by Garcia.

El Manchón, a large and remote settlement, initially displayed no evidence of Spanish presence. The site consisted of three steep sectors, two of which displayed long house foundations, some with interior rooms and religious sanctuaries, patios, and a configuration that was conceptually Mesoamerican but unrelated to any known ethnic groups such as the Aztec. In between the two was an area that contained mounds of slag (the nonmetallic material that separates out during smelting from the pure metal, which floats to the surface).

The Spanish invaders urgently needed enormous quantities of copper and tin to make the bronze for their cannons and other armaments, Hosler says, and this is documented in the historical and archival records. But “they didn’t know how to smelt,” she says, whereas archaeological data suggest the indigenous people had already been smelting copper at this settlement for several hundred years, mostly to make ritual or ceremonial materials such as bells and amulets. These artisans were highly skilled, and in Guerrero and elsewhere had been producing complex alloys including copper-silver, copper-arsenic, and copper-tin for hundreds of years, working on a small scale using blowpipes and crucibles to smelt the copper and other ores.

But the Spanish desperately required large quantities of copper and tin, and in consultation with indigenous smelters introduced some European technology into the process. Hosler and her colleagues excavated an enigmatic feature that consisted of two parallel courses of stones leading toward a large cake of slag in the smelting area. They identified this as the remains of a thus-far-undocumented hybrid type of closed furnace design, powered by a modified hand-held European bellows. A small regional museum in highland Guerrero illustrates just such a hybrid furnace design, including the modified European-introduced bellows system, capable of producing large volumes of copper. But no actual remains of such furnaces had previously been found.

The period when this site was occupied spanned from about 1240 to 1680, Hosler says, and may have extended to both earlier and later times.

The Guerrero site, which Hosler excavated over four field seasons before work had to be suspended because of local drug cartel activity, contains large heaps of copper slag, built up over centuries of intensive use. But it took a combination of the physical evidence, analysis of the ore and slags, the archaeological feature in the the smelting area, the archival work, and reconstruction drawing to enable identification of the centuries of interdependence of the two populations in this remote outpost.

Earlier studies of the composition of the slag at the site, by Hosler and some of her students, revealed that it had formed at a temperature of 1150 degrees Celsius, which could not have been achieved with just the blowpipe system and would have required bellows. That helps to confirm the continued operation of the site long into the colonial period, Hosler says.

Years of work went into trying to find ways to date the different deposits of slag at the site. The team also tried archaeomagnetic data but found that the method was not effective for the materials in that particular region of Mexico. But the written historical record proved key to making sense of the wide range of dates, which reflected centuries of use of the site.

Documents sent back to Spain in the early colonial period described the availability of the locally produced copper, and the colonists’ successful tests of using it to cast bronze artillery pieces. Documents also described the bargains made by the indigenous producers to gain economic privileges for their people, based on their specialized metallurgical knowledge.

“We know from documents that the Europeans figured out that the only way they could smelt copper was to collaborate with the indigenous people who were already doing it,” Hosler says. “They had to cut deals with the indigenous smelters.”

Hosler says that “what’s so interesting to me is that we were able to use traditional archeological methods and data from materials analysis as well as ethnographic data” from the furnace in a museum in the area, “and historical and archival material from 16th century archives in Portugal, Spain, and Mexico, then to put all the data from these distinct disciplines together into an explanation that is absolutely solid.”

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European colonists cooperated with indigenous people to smelt copper. Alexas Fotos, Pixabay, Public Domain

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Article Source: MASSACHUSETTS INSTITUTE OF TECHNOLOGY news release

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UNIVERSITY OF KENT—A new study led by the University of Kent has found evidence that human ancestors as recent as two million years ago may have regularly climbed trees.

Walking on two legs has long been a defining feature to differentiate modern humans, as well as extinct species on our lineage (aka hominins), from our closest living ape relatives: chimpanzees, gorillas and orangutans. This new research, based on analysis of fossil leg bones, provides evidence that a hominin species (believed to be either Paranthropus robustus or early Homo) regularly adopted highly flexed hip joints; a posture that in other non-human apes is associated with climbing trees.

These findings came from analyzing and comparing the internal bone structures of two fossil leg bones from South Africa, discovered over 60 years ago and believed to have lived between 1 and 3 million years ago. For both fossils, the external shape of the bones were very similar showing a more human-like than ape-like hip joint, suggesting they were both walking on two legs. The researchers examined the internal bone structure because it remodels during life based on how individuals use their limbs. Unexpectedly, when the team analyzed the inside of the spherical head of the femur, it showed that they were loading their hip joints in different ways.

The research project was led by Dr Leoni Georgiou, Dr Matthew Skinner and Professor Tracy Kivell at the University of Kent’s School of Anthropology and Conservation, and included a large international team of biomechanical engineers and palaeontologists. These results demonstrate that novel information about human evolution can be hidden within fossil bones that can alter our understanding of when, where and how we became the humans we are today.

Dr Georgiou said: ‘It is very exciting to be able to reconstruct the actual behavior of these individuals who lived millions of years ago and every time we CT scan a new fossil it is a chance to learn something new about our evolutionary history.’

Dr Skinner said: ‘It has been challenging to resolve debates regarding the degree to which climbing remained an important behavior in our past. Evidence has been sparse, controversial and not widely accepted, and as we have shown in this study the external shape of bones can be misleading. Further analysis of the internal structure of other bones of the skeleton may reveal exciting findings about the evolution of other key human behaviors such as stone tool making and tool use. Our research team is now expanding our work to look at hands, feet, knees, shoulders and the spine.’

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Photograph of the fossil and artifact-bearing surface exposed deposits of the Sterkfontein Cave site. View looking towards the west. Dominic Stratford

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Article Source: UNIVERSITY OF KENT news release

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UNIVERSITY OF GÖTTINGEN—Over 80,000 years ago, Neanderthals were already feeding themselves regularly on mussels, fish and other marine life. The first robust evidence of this has been found by an international research team with the participation of the University of Göttingen during an excavation in the cave of Figueira Brava in Portugal. Dr Dirk Hoffmann at the Göttingen Isotope Geology Department dated flowstone layers – calcite deposits that form like stalagmites from dripping water – using the uranium-thorium method, and was thus able to determine the age of the excavation layers to between 86,000 and 106,000 years. This means that the layers date from the period in which the Neanderthals settled in Europe. The use of the sea as a source of food at that time has so far only been attributed to anatomically modern humans (Homo sapiens) in Africa. The results of the study* were published in the journal Science.

The cave of Figueira Brava is located 30 kilometers south of Lisbon on the slopes of the Serra da Arrábida. Today it is located directly on the waterfront, but at that time it was up to two kilometers from the coast. The research team, coordinated by the first author of the study, Professor João Zilhão from the University of Barcelona, found that the Neanderthals living there were able to routinely harvest mussels and fish, and to hunt seals. Their diet included mussels, crustaceans and fish as well as waterfowl and marine mammals such as dolphins and seals. Food from the sea is rich in omega-3 fatty acids and other fatty acids that promote the development of brain tissue.

The cave yielded remains of this marine life associated with the excavation layers dated to the time period between 86,000 and 106,000 years. The site also yielded tens of thousands of stone tools identified with Middle Paleolithic technology, and a tooth that exhibited features typically characteristic of neanderthals.

Until now, it has always been suspected that this consumption increased the cognitive abilities of the human populations in Africa. “Among other influences, this could explain the early appearance of a culture of modern people that used symbolic artifacts, such as body painting with ochre, the use of ornaments or the decoration of containers made of ostrich eggs with geometric motifs,” explains Hoffmann. “Such behavior reflects human’s capacity for abstract thought and communication through symbols, which also contributed to the emergence of more organized and complex societies of modern humans”.

The recent results of the excavation of Figueira Brava now confirm that if the habitual consumption of marine life played an important role in the development of cognitive abilities, this is as true for Neanderthals as it is for anatomically modern humans. Hoffmann and his co-authors previously found that Neanderthals made cave paintings in three caves on the Iberian Peninsula more than 65,000 years ago and that perforated and painted shells must also be attributed to the Neanderthals.

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View on the Figueira Brava cave with its three entrances. João Zilhão

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Horizontal exposure of a mussel shell bed. João Zilhão

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Cracked-open and burnt fragments of pincers of the edible crab (cancer pagurus). João Zilhão

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Article Source: Edited and adapted from the UNIVERSITY OF GÖTTINGEN news release

*J. Zilhão et al., Last Interglacial Iberian Neandertals as fisher-hunter-gatherers, Science, 10.1126/science.aaz7943

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Science Advances—New artifacts uncovered at the Waim archaeological site in the highlands of New Guinea – including a fragment of the earliest symbolic stone carving in Oceania – illustrate a shift in human behavior between 5050 and 4200 years ago in response to the widespread emergence of agriculture, ushering in a regional Neolithic Era similar to the Neolithic in Eurasia. The location and pattern of the artifacts at the site suggest a fixed domestic space and symbolic cultural practices, hinting that the region began to independently develop hallmarks of the Neolithic about 1000 years before Lapita farmers from Southeast Asia arrived in New Guinea. While scientists have known that wetland agriculture originated in the New Guinea highlands between 8000 and 4000 years ago, there has been little evidence for corresponding social changes like those that occurred in other parts of the world. To better understand what life was like in this region as agriculture spread, Ben Shaw et al. excavated and examined a trove of artifacts from the recently identified Waim archaeological site. “What is truly exciting is that this was the first time these artifacts have been found in the ground, which has now allowed us to determine their age with radiocarbon dating,” Shaw said. The researchers analyzed a stone carving fragment depicting the brow ridge of a human or animal face, a complete stone carving of a human head with a bird perched on top (recovered by Waim residents), and two ground stone pestle fragments with traces of yam, fruit and nut starches on their surfaces. They also identified an obsidian core that provides the first evidence for long-distance, off-shore obsidian trade, as well as postholes where house posts may have once stood.

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The first pestle found during initial spade pitting, the find that started it all. Ben Shaw

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Ben recording postholes in the excavated section. Judith Field

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Complex stone artefacts recovered by Waim residents which initiated excavations. Ben Shaw

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Waim base camp where the team stayed during excavation. Judith Field

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Article Source: Science Advances news release

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WELLCOME TRUST SANGER INSTITUTE—A new study has provided the most comprehensive analysis of human genetic diversity to date, after the sequencing of 929 human genomes by scientists at the Wellcome Sanger Institute, the University of Cambridge and their collaborators. The study uncovers a large amount of previously undescribed genetic variation and provides new insights into our evolutionary past, highlighting the complexity of the process through which our ancestors diversified, migrated and mixed throughout the world.

The resource, published in Science (20 March), is the most detailed representation of the genetic diversity of worldwide populations to date. It is freely available to all researchers to study human genetic diversity, including studies of genetic susceptibility to disease in different parts of the world.

The consensus view* of human history tells us that the ancestors of present-day humans diverged from the ancestors of extinct Neanderthal and Denisovan groups around 500,000-700,000 years ago, before the emergence of ‘modern’ humans in Africa in the last few hundred thousand years.

Around 50,000-70,000 years ago, some humans expanded out of Africa and soon after mixed with archaic Eurasian groups. After that, populations grew rapidly, with extensive migration and mixture as many groups transitioned from hunter-gatherers to food producers over the last 10,000 years.

This study is the first to apply the latest high-quality sequencing technology to such a large and diverse set of humans, covering 929 genomes from 54 geographically, linguistically and culturally diverse populations from across the globe. The sequencing and analysis of these genomes, which are part of the Human Genome Diversity Project (HGDP)-CEPH panel**, now provides unprecedented detail of our genetic history.

The team found millions of previously unknown DNA variations that are exclusive to one continental or major geographical region. Though most of these were rare, they included common variations in certain African and Oceanian populations that had not been identified by previous studies.

Variations such as these may influence the susceptibility of different populations to disease. However, medical genetics studies have so far predominantly been conducted in populations of European ancestry, meaning that any medical implications that these variants might have are not known. Identifying these novel variants represents a first step towards fully expanding the study of genomics to underrepresented populations.

However, no single DNA variation was found to be present in 100 per cent of genomes from any major geographical region while being absent from all other regions. This finding underlines that the majority of common genetic variation is found across the globe.

Dr Anders Bergström, of the Francis Crick Institute and an alumnus of the Wellcome Sanger Institute, said: “The detail provided by this study allows us to look deeper into human history, particularly inside Africa where less is currently known about the timescale of human evolution. We find that the ancestors of present-day populations diversified through a gradual and complex process mostly during the last 250,000 years, with large amounts of gene flow between these early lineages. But we also see evidence that small parts of human ancestries trace back to groups that diversified much earlier than this.”

Hélène Blanché, Head of the Biological Resource Centre at the Centre d’Etude du Polymorphisme Humain (CEPH) in Paris, France, said: “The Human Genome Diversity Project resource has facilitated many new discoveries about human history in the past two decades. It is exciting to see that with the latest genomic sequencing technology, these genomes will continue to help us understand our species and how we have evolved.”

The study also provides evidence that the Neanderthal ancestry of modern humans can be explained by just one major ‘mixing event’, most likely involving several Neanderthal individuals coming into contact with modern humans shortly after the latter had expanded out of Africa. In contrast, several different sets of DNA segments inherited from Denisovans were identified in people from Oceania and East Asia, suggesting at least two distinct mixing events.

The discovery of small amounts of Neanderthal DNA in west African people, most likely reflecting later genetic backflow into Africa from Eurasia, further highlights how human genetic history is characterized by multiple layers of complexity. Until recently, it was thought that only people outside sub-Saharan Africa had Neanderthal DNA.

Dr Chris Tyler-Smith, recently retired from the Wellcome Sanger Institute, said: “Though this resource is just the beginning of many avenues of research, already we can glimpse several tantalizing insights into human history. It will be particularly important for better understanding human evolution in Africa, as well as facilitating medical research for the full diversity of human ancestries.”

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The latest technology and techniques are being used to sequence the human genome, allowing scientists to peer into our deep evolutionary history. Courtesy Kenneth Rodrigues, Pixabay

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Article Source: WELLCOME TRUST SANGER INSTITUTE news release

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UNIVERSITY OF THE WITWATERSRAND—High-resolution micro-CT scanning of the skull of the fossil specimen known as “Little Foot” has revealed some aspects of how this Australopithecus species used to live more than 3 million years ago.

The meticulous excavation, cleaning and scanning of the skull of the ~3.67 million-year-old fossil specimen has revealed the most complete Australopithecus adult first cervical vertebra yet found. A description of the vertebra by Wits University researchers Dr Amélie Beaudet and the Sterkfontein team was published in the Scientific Reports. This research program is supported by the the Centre of Excellence in Palaeosciences, Scientific Palaeontological Trust, National Research Foundation, University of the Witwatersrand and the French National Centre for Scientific Research through the French Institute of South Africa.

The first cervical vertebra (or atlas) plays a crucial role in vertebrate biology. Besides acting as the connection between the head and the neck, the atlas also plays a role in how blood is supplied to the brain via the vertebral arteries.

By comparing the atlas of “Little Foot” with other fossils from South and East Africa as well as living humans and chimpanzees, the Wits University team shows that Australopithecus was capable of head movements that differ from modern humans.

“The morphology of the first cervical vertebra, or atlas, reflects multiple aspects of an organism’s life,” says Beaudet, the lead author of the study. “In particular, the nearly complete atlas of ‘Little Foot’ has the potential to provide new insights into the evolution of head mobility and the arterial supply to the brain in the human lineage.”

The shape of the atlas determines the range of head motions while the size of the arteries passing through the vertebrae to the skull is useful for estimating blood flow supplying the brain.

“Our study shows that Australopithecus was capable of head movements that differ from us. This could be explained by the greater ability of Australopithecus to climb and move in the trees. However, a southern African Australopithecus specimen younger than ‘Little Foot’ (probably younger by about 1 million years) may have partially lost this capacity and spent more time on the ground, like us today.”

The overall dimensions and shape of the atlas of “Little Foot” are similar to living chimpanzees. More specifically, the ligament insertions (that could be inferred from the presence and configuration of bony tubercles) and the morphology of the facet joints linking the head and the neck all suggest that “Little Foot” was moving regularly in trees.

Because “Little Foot” is so well-preserved, blood flow supply to the brain could also be estimated for the first time, using evidence from the skull and vertebrae. These estimations demonstrate that blood flow, and thus the utilization of glucose by the brain, was about three times lower than in living humans, and closer to the those of living chimpanzees.

“The low investment of energy into the brain of Australopithecus could be tentatively explained by a relatively small brain of the specimen (around 408cm3), a low quality diet (low proportion of animal products) or high costs of other aspects of the biology of Australopithecus (such as upright walking). In any case, this might suggest that the human brain’s vascular system emerged much later in our history.”

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Pictures of the ‘Little Foot’ skull. The view from the bottom (right) shows the original position of the first cervical vertebra still embedded in the matrix. R.J. Clarke

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Comparison of the nearly intact first cervical vertebra of ‘Little Foot’ and two other Australopithecus from Sterkfontein in South Africa and from Hadar in Ethiopia showing how complete ‘Little Foot’ is compared to the rest of the fossil record. Amélie Beaudet/Wits University

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Article Source: UNIVERSITY OF THE WITWATERSRAND news release

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If you liked this article, you may like this one:

Sterkfontein: A History of Evolution in the Cradle of Humanity

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UNIVERSITY OF EXETER—Mysterious bone circles made from the remains of dozens of mammoths have revealed clues about how ancient communities survived Europe’s ice age.

About 70 of these structures are known to exist in Ukraine and the west Russian Plain.

New analysis shows the bones at one site are more than 20,000 years old, making it the oldest such circular structure built by humans discovered in the region. The bones were likely sourced from animal graveyards, and the circle was then hidden by sediment and is now a foot below current surface level.

The majority of the bones found at the site investigated, in the Russian Plains, are from mammoths. A total of 51 lower jaws and 64 individual mammoth skulls were used to construct the walls of the 30ft by 30ft structure and scattered across its interior. Small numbers of reindeer, horse, bear, wolf, red fox and arctic fox bones were also found.

Archaeologists from the University of Exeter have also found for the first time the remains of charred wood and other soft non-woody plant remains within the circular structure, situated just outside the modern village of Kostenki, about 500km south of Moscow. This shows people were burning wood as well as bones for fuel, and the communities who lived there had learned where to forage for edible plants during the Ice Age. The plants could also have been used for poisons, medicines, string or fabric. More than 50 small charred seeds were also found – the remains of plants growing locally or possibly food remains from cooking and eating.

Dr Alexander Pryor, who led the study, said: “Kostenki 11 represents a rare example of Palaeolithic hunter-gatherers living on in this harsh environment. What might have brought ancient hunter gatherers to this site? One possibility is that the mammoths and humans could have come to the area on masse because it had a natural spring that would have provided unfrozen liquid water throughout the winter – rare in this period of extreme cold.

“These finds shed new light on the purpose of these mysterious sites. Archaeology is showing us more about how our ancestors survived in this desperately cold and hostile environment at the climax of the last ice age. Most other places at similar latitudes in Europe had been abandoned by this time, but these groups had managed to adapt to find food, shelter and water.”

The last ice age, which swept northern Europe between 75-18,000 years ago, reached its coldest and most severe stage at around 23-18,000 years ago, just as the site at Kostenki 11 was being built. Climate reconstructions indicate at the time summers were short and cool and winters were long and cold, with temperatures around -20 degrees Celsius or colder. Most communities left the region, likely because of lack of prey to hunt and plant resources they depended upon for survival. Eventually the bone circles were also abandoned as the climate continued to get colder and more inhospitable.

Previously archaeologists have assumed that the circular mammoth bone structures were used as dwellings, occupied for many months at a time. The new study suggests this may not always have been the case as the intensity of activity at Kostenki 11 appears less than would be expected from a long term base camp site.

Other finds include more than 300 tiny stone and flint chips just a few millimeters in size, debris left behind the site’s inhabitants as they knapped stone nodules into sharp tools with distinctive shapes used for tasks such as butchering animals and scraping hides.

The research, conducted by academics from the University of Exeter, University of Cambridge, Kostenki State Museum Preserve, University of Colorado Boulder and the University of Southampton, is published in the journal Antiquity.

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Above and below: The majority of the bones found at the site investigated, in the Russian Plains, are from mammoths. A total of 51 lower jaws and 64 individual mammoth skulls were used to construct the walls of the 30ft by 30ft structure and scattered across its interior. Alex Pryor

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Article Source: UNIVERSITY OF EXETER news release

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Science Advances—Archaeologists have excavated a 3400-year-old ballcourt in the mountains of Oaxaca, Mexico. The discovery challenges current assumptions about the origin and evolution of the ballgame that held ritual and political importance across Mesoamerica, a pre-Columbian cultural region encompassing Guatemala, Belize, most of Mexico, and parts of Honduras and El Salvador. Researchers have found more than 2300 probable ballcourts, and to the region’s best-known civilizations, the Maya and the Aztec, the game symbolized the regeneration of life and the maintenance of cosmic order. Because chemical analysis of several Aztec balls showed that their rubber came from Castilla elastica, a tree species associated with the plains of southern Mesoamerica, archaeologists have favored the lowlands as the place of origin and primary evolution of the ballgame. Additionally, the oldest known ballcourt, dated to 1650 B.C., is at Paso de la Amada in the coastal lowlands of southern Chiapas, Mexico. At the site of Etlatongo in Oaxaca, Mexico, however, Jeffrey Blomster and Victor Chavez discovered two ballcourts, the older of which dates to 1374 B.C., pushing back the appearance of such structures in the Mesoamerican highlands by approximately 800 years. Based on this finding, Blomster and Chavez argue that both lowland and highland societies contributed to the evolution of the Mesoamerican ballgame. Because nearly a millennium separates the Paso de la Amada and Etlatongo sites from the next ballcourts documented in their respective regions, future research could provide context by uncovering ballcourts at more highland and lowland sites.

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Location of Etlatongo in Mesoamerica and the setting of its ballcourt. (A) Map showing location of Etlatongo in the Mixteca Alta and other referenced sites in Mesoamerica. (B) Aerial view of the ballcourt on Mound 1-1 (colored blue) in relation to domestic space excavated in Operations G & I (purple) to the north. Blomster and Salazar Chávez, Sci. Adv. 2020; 6 : eaay6964

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The surface of Mound 1-1 at Etlatongo before excavations began in 2015. Deep below the surface, the project found the ballcourts. Note the old threshing floor on the surface, no longer in use, from the time when these lands belonged to an hacienda. Formative Etlatongo Project

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Excavations beginning on Etlatongo Mound 1-1 in the early morning. A small pile of dirt from the excavations has already accumulated on the southern portion of the mound. The modern town of San Mateo Etlatongo is at the foot of the hill in the background of the photo, obscured by the low hanging cloud. Formative Etlatongo Project

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Etlatongo’s ballcourts, Structure 1-2 and Structure 1-3, reconstructed plan views and related cross-sections, with separate scales, based on the excavations. Photograph shows architectural details of both ballcourts; the white rectangles over the plan views show excavation locations. Formative Etlatongo Project

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Early ballcourts in Mesoamerica. Comparison of early ballcourt cross-sections (to scale), with earliest on top, with plan views (not to scale) from Paso de la Amada (Chiapas) and La Laguna (Tlaxcala). Blomster and Salazar Chávez, Sci. Adv. 2020; 6 : eaay6964

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Etlatongo ballplayer figurine. One of numerous ceramic ballplayers from the termination event, front view shows a thick belt or yoke with a loincloth project from it, while the profile view illustrates broken tripod support at bottom, which allowed the figurine to stand, and whistle chamber above it. Blomster and Salazar Chávez, Sci. Adv. 2020; 6 : eaay6964

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Additional ceramic ballplayer figurines found above the ballcourt. Both wear thick belts or yokes with a loincloth; the figure on the left also has an additional costume element, a collar or pectoral, over the chest. Formative Etlatongo Project

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Article Source: Science Advances news release

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PLOS—The El Algar society thrived in complex hilltop settlements across the Iberian Peninsula from 2200-1550 cal BCE, and gravesites and settlement layouts provide strong evidence of a marked social hierarchy.

Knipper and colleagues conducted carbon and nitrogen isotope analysis at two different El Algar hilltop settlements: the large fortified urban site La Bastida (in present-day Totana, Murcia), and the smaller settlement Gatas (Turre, Almería). Their sample included remains of 75 human individuals from across social strata, 28 bones from domestic animals and wild deer, charred barley (75 grains total), and charred wheat (29 grains) from the middle and late phases of El Algar civilization across the two sites.

The sampled human individuals showed no significant difference between isotope values for males and for females, suggesting that diets may have been similar between genders. However, “elite” individuals at La Bastida showed higher levels of both carbon and nitrogen. This might have implied that the people of La Bastida consumed higher levels of animal-based food, but the authors suggest that the isotope value differences between La Bastida and Gatas could in fact have resulted from similar dietary compositions. Nitrogen values are similar at both sites for barley, but higher for the domestic animals at La Bastida, meaning that diets with similar relative contributions of barley and meat/dairy products would have led to higher nitrogen values in the humans at La Bastida compared to Gatas.

The researchers found a strong reliance on cereal farming, supplemented by livestock, in the El Algar economy. The range and values of carbon in the barley and wheat sample reflect what was likely a dry, unirrigated landscape, though nitrogen levels in the cereal crops suggest the El Algar people applied animal manure to their fields. Cereals and their by-products appear to have contributed substantially to the forage of domesticated sheep/goats, cattle and pigs.

Though the sample used in this study* is relatively small, and there are limitations to what can be sampled with this type of isotope analysis, this study shows the importance of considering the complete trophic chain in order to adequately interpret isotope data from human remains–and also demonstrates the sophistication of El Algar farming techniques.

Knipper adds: “It is essential to not only investigate human remains, but also comparative samples of different former food stuffs as well as to interpret the data in the light of the archaeological and social historical context.”

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La Bastida 3D reconstruction. Dani Méndez-REVIVES

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Article Source: PLOS One news release

*Knipper C, Rihuete-Herrada C, Voltas J, Held P, Lull V, Micó R, et al. (2020) Reconstructing Bronze Age diets and farming strategies at the early Bronze Age sites of La Bastida and Gatas (southeast Iberia) using stable isotope analysis. PLoS ONE 15(3): e0229398. https://doi.org/10.1371/journal.pone.0229398

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UNIVERSITY OF MICHIGAN—ANN ARBOR–A clump of grass grows on an outcrop of shale 33,000 years ago. An ostrich pecks at the grass, and atoms taken up from the shale and into the grass become part of the eggshell the ostrich lays.

A member of a hunter-gatherer group living in southern Africa’s Karoo Desert finds the egg. She eats it, and cracks the shell into dozens of pieces. Drilling a hole, she strings the fragments onto a piece of sinew and files them into a string of beads.

She gifts the ornaments to friends who live to the east, where rainfall is higher, to reaffirm those important relationships. They, in turn, do the same, until the beads eventually end up with distant groups living high in the eastern mountains.

Thirty-three thousand years later, a University of Michigan researcher finds the beads in what is now Lesotho, and by measuring atoms in the beads, provides new evidence for where these beads were made, and just how long hunter-gatherers used them as a kind of social currency.

In a study published in the Proceedings of the National Academy of Science, U-M paleolithic archeologist Brian Stewart and colleagues establish that the practice of exchanging these ornaments over long distances spans a much longer period of time than previously thought.

“Humans are just outlandishly social animals, and that goes back to these deep forces that selected for maximizing information, information that would have been useful for living in a hunter-gatherer society 30,000 years ago and earlier,” said Stewart, assistant professor of anthropology and assistant curator of the U-M Museum of Anthropological Archaeology.

“Ostrich eggshell beads and the jewelry made from them basically acted like Stone Age versions of Facebook or Twitter ‘likes,’ simultaneously affirming connections to exchange partners while alerting others to the status of those relationships.”

Lesotho is a small country of mountain ranges and rivers. It has the highest average of elevation in the continent and would have been a formidable place for hunter-gatherers to live, Stewart says. But the fresh water coursing through the country and belts of resources, stratified by the region’s elevation, provided protection against swings in climate for those who lived there, as early as 85,000 years ago.

Anthropologists have long known that contemporary hunter-gatherers use ostrich eggshell beads to establish relationships with others. In Lesotho, archeologists began finding small ornaments made of ostrich eggshell. But ostriches don’t typically live in that environment, and the archeologists didn’t find evidence of those ornaments being made in that region–no fragments of unworked eggshell, or beads in various stages of production.

So when archeologists began discovering eggshell beads without evidence of production, they suspected the beads arrived in Lesotho through these exchange networks. Testing the beads using strontium isotope analysis would allow the archeologists to pinpoint where they were made.

Strontium-87 is the daughter isotope of the radioactive element rubidium-87. When rubidium-87 decays it produces strontium-87. Older rocks such as granite and gneiss have more strontium than younger rocks such as basalt. When animals forage from a landscape, these strontium isotopes are incorporated into their tissues.

Lesotho is roughly at the center of a bullseye-shaped geologic formation called the Karoo Supergroup. The supergroup’s mountainous center is basalt, from relatively recent volcanic eruptions that formed the highlands of Lesotho. Encircling Lesotho are bands of much older sedimentary rocks. The outermost ring of the formation ranges between 325 and 1,000 kilometers away from the Lesotho sites.

To assess where the ostrich eggshell beads were made, the research team established a baseline of strontium isotope ratios–that is, how much strontium is available in a given location–using vegetation and soil samples as well samples from modern rodent tooth enamel from museum specimens collected from across Lesotho and surrounding areas.

According to their analysis, nearly 80% of the beads the researchers found in Lesotho could not have originated from ostriches living near where the beads were found in highland Lesotho.

“These ornaments were consistently coming from very long distances,” Stewart said. “The oldest bead in our sample had the third highest strontium isotope value, so it is also one of the most exotic.”

Stewart found that some beads could not have come from closer than 325 kilometers from Lesotho, and may have been made as far as 1,000 kilometers away. His findings also establish that these beads were exchanged during a time of climactic upheaval, about 59 to 25 thousand years ago. Using these beads to establish relationships between hunter-gatherer groups ensured one group access to others’ resources when a region’s weather took a turn for the worse.

“What happened 50,000 years ago was that the climate was going through enormous swings, so it might be no coincidence that that’s exactly when you get this technology coming in,” Stewart said. “These exchange networks could be used for information on resources, the condition of landscapes, of animals, plant foods, other people and perhaps marriage partners.”

Stewart says while archeologists have long accepted that these exchange items bond people over landscapes in the ethnographic Kalahari, they now have firm evidence that these beads were exchanged over huge distances not only in the past, but for over a long period of time. This study places another piece in the puzzle of how we persisted longer than all other humans, and why we became the globe’s dominant species.

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Above and below: Archeologists work at rock shelters at Sehonghong and Melikane in southern Africa. Brian Stewart

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Above and below: Ostrich eggshell beads have been used to cement relationships in Africa for more than 30,000 years. John Klausmeyer, Yuchao Zhao and Brian Stewart

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Article Source: University of Michigan news release

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Science Advances—Scientists have discovered new fragments of two Homo erectus skulls alongside different types of stone tool technologies, helping to dispel the assumption that these different technologies were used by different species of hominins or in different eras. The skull fragments also hold clues to possible differences between male and female members of H. erectus, a species of human ancestor that appeared about two million years ago, as well as to the lifestyle and diet of the species. Archaeologists and paleoanthropologists classify stone tools by their complexity and the time period in which they were used. “Mode I” tools are those with simple modifications—a few pieces chipped off to make sharp edges. Mode II tools are created by removing flakes on both sides of the stone resulting in more refined, “pear-shaped” hand axes. It was previously assumed that H. erectus invented Mode II tools, which succeeded Mode I tools used by earlier hominins, though some researchers have proposed a more complex history. Now, Sileshi Semaw and colleagues have discovered H. erectus skulls in close association with both kinds of tools in Ethiopia. They date one skull to 1.26 million years ago and the other to 1.6 to 1.5 million years ago. They interpret these findings to mean H. erectus used both technologies concurrently over hundreds of thousands of years, indicating the species was behaviorally flexible and diverse. The researchers also analyzed the features of the skulls, one male and the other female. The female skull was smaller and slimmer, indicating H. erectus may have been sexually dimorphic. The isotope data point to these individuals as having a broad, varied diet – consisting of plants, eggs, insects and more – but additional isotopic data from more samples over a larger geographic range would be needed to confirm this, the authors say.

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The DAN5 cranium, held by Dr. S. Semaw.
Michael J. Rogers, Southern Connecticut State University

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The DAN5 cranium, view from the front and above. Michael J. Rogers, Southern Connecticut State University

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Two opposing views of Oldowan stone tools from DAN5. Michael J. Rogers, Southern Connecticut State University

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Two opposing views of Acheulian stone tools from DAN5. Michael J. Rogers, Southern Connecticut State University

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Map of the Gona Study Area. Michael J. Rogers, Southern Connecticut State University

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Article Source: Science Advances news release

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MAX PLANCK INSTITUTE FOR THE SCIENCE OF HUMAN HISTORY—The historic economies of Mongolia are among the least understood of any region in the world. The region’s persistent, extreme winds whisk away signs of human activity and prevent the buildup of sediment which archaeologists rely on to preserve the past. Today crop cultivation comprises only a small percent of Mongolia’s food production, and many scholars have argued that Mongolia presents a unique example of dense human populations and hierarchical political systems forming without intensive farming or stockpiling grains.

The current study*, led by Dr. Shevan Wilkin of the Max Planck Institute for the Science of Human History provides, for the first time, a detailed glimpse into the diets and lives of ancient Mongolians, underscoring the importance of millets during the formation of the earliest empires on the steppe.

Isotopic analysis and the imperial importance of millets

Collaborating with archaeologists from the National University of Mongolia and the Institute of Archaeology in Ulaanbaatar, Dr. Wilkin and her colleagues from the MPI SHH sampled portions of teeth and rib bones from 137 previously excavated individuals. The skeletal fragments were brought back to the ancient isotope lab in Jena, Germany, where researchers extracted bone collagen and dental enamel to examine the ratios of stable nitrogen and carbon isotopes within. With these ratios in hand, scientists were able to reconstruct the diets of people who lived, ate, and died hundreds to thousands of years ago.

Researchers tracked the trends in diet through the millennia, creating a “dietscape” which clearly showed significant differences between the diets of Bronze Age peoples and those who lived during the Xiongnu and Mongol Empires. A typical Bronze Age Mongolian diet was based on milk and meat, and was likely supplemented with small amounts of naturally available plants. Later, during the Xiongnu Empire, human populations displayed a larger range of carbon values, showing that some people remained on the diet common in the Bronze Age, but that many others consumed a high amount of millet-based foods. Interestingly, those living near the imperial heartlands appear to have been consuming more millet-based foods than those further afield, which suggests imperial support for agricultural efforts in the more central political regions. The study also shows an increase in grain consumption and increasing dietary diversity through time, leading up to the well-known Mongolian Empire of the Khans.

Rethinking Mongolian prehistory

The new discoveries presented in this paper show that the development of the earliest empires in Mongolia, like in other parts of the world, was tied to a diverse economy that included the local or regional production of grain. Dr. Bryan K. Miller, a co-author who studies the historical and archaeological records of Inner Asian empires, remarks that “these regimes were like most empires, in that they directed intricate political networks and sought to amass a stable surplus – in this case a primarily pastoral one that was augmented by other resources like millet.”

“In this regard,” Dr. Miller adds, “this study brings us one step closer to understanding the cultural processes that led humanity into the modern world.”

The view that everyone in Mongolian history was a nomadic herder has skewed discussions concerning social development in this part of the world. Dr. Wilkin notes that “setting aside our preconceived ideas of what prehistory looked like and examining the archaeological record with modern scientific approaches is forcing us to rewrite entire sections of humanity’s past.” Dr. Spengler, the director of the archaeobotany labs at the MPI SHH, emphasizes the importance of this discovery, noting that “this study pulls the veil of myth and lore off of the real people who lived in Mongolia millennia ago and lets us peak into their lives.”

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Mongolian landscape with pastoral herd of sheep and goats. Alicia Ventresca Miller

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Cultivated land in northern Mongolia. Alicia Ventresca Miller

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Horses are still used by many for transport across Mongolia. Shevan Wilkin

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Article Source: MAX PLANCK INSTITUTE FOR THE SCIENCE OF HUMAN HISTORY news release

*Shevan Wilkin, Alicia Ventresca Miller, Bryan K. Miller, Robert N. Spengler, William T. T. Taylor, Ricardo Fernandes, Madeleine Bleasdale, Jana Zech, S. Ulziibayar, Erdene Myagmar, Nicole Boivin, Patrick Roberts, Economic Diversification Supported the Growth of Mongolia’s Nomadic Empires, Scientific Reports, DOI: 10.1038/s41598-020-60194-0

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