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Evolution: South Africa’s hominin record is a fair-weather friend

UNIVERSITY OF CAPE TOWN—New research from an international team of scientists led by University of Cape Town isotope geochemist Dr Robyn Pickering is the first to provide a timeline for fossils from the caves within the Cradle of Humankind. It also sheds light on the climate conditions of our earliest ancestors in the area.

Published online in the journal Nature on 21 November 2018, the work corrects assumptions that the region’s fossil-rich caves could never be related to each other. In fact, the research suggests fossils from Cradle caves date to just six specific time periods.

“Unlike previous dating work, which often focused on one cave, sometimes even just one chamber of the cave, we are providing direct ages for eight caves and a model to explain the age of all the fossils from the entire region,” says Dr Robyn Pickering.

“Now we can link together the findings from separate caves and create a better picture of evolutionary history in southern Africa.”

The Cradle of Humankind is a World Heritage Site made up of complex fossil-bearing caves. It’s the world’s richest early hominin site and home to nearly 40% of all known human ancestor fossils, including the famous Australopithecus africanus skull nicknamed Mrs Ples.

Using uranium-lead dating, researchers analysed 28 flowstone layers that were found sandwiched between fossil-rich sediment in eight caves across the Cradle. The results revealed that the fossils in these caves date to six narrow time-windows between 3.2 and 1.3 million years ago.

“The flowstones are the key,” says Pickering. “We know they can only grow in caves during wet times, when there is more rain outside the cave. By dating the flowstones, we are picking out these times of increased rainfall. We therefore know that during the times in between, when the caves were open, the climate was drier and more like what we currently experience.”

This means the early hominins living in the Cradle experienced big changes in local climate, from wetter to drier conditions, at least six times between 3 and 1 million years ago. However, only the drier times are preserved in the caves, skewing the record of early human evolution.

Up until now, the lack of dating methods for Cradle fossils made it difficult for scientists to understand the relationship between East and South Africa hominin species. Moreover, the South African record has often been considered undateable compared to East Africa where volcanic ash layers allow for high resolution dating.

Professor Andy Herries, a co-author in the study at La Trobe University in Australia, notes that “while the South African record was the first to show Africa as the origin point for humans, the complexity of the caves and difficultly dating them has meant that the South African record has remained difficult to interpret.”

“In this study we show that the flowstones in the caves can act almost like the volcanic layers of East Africa, forming in different caves at the same time, allowing us to directly relate their sequences and fossils into a regional sequence,” he says.

Dr Pickering began dating the Cradle caves back in 2005 as part of her PhD research. This new publication is the result of 13 years of work and brings together a team of 10 scientists from South Africa, Australia and the US. The results return the Cradle to the forefront and open new opportunities for scientists to answer complex questions about human history in the region.

“Robyn and her team have made a major contribution to our understanding of human evolution,” says leading palaeoanthropologist Professor Bernard Wood, of the Center for the Advanced Study of Human Paleobiology at the George Washington University in the USA, who is not an author on the study.

“This is the most important advance to be made since the fossils themselves were discovered. Dates of fossils matter a lot. The value of the southern African evidence has been increased many-fold by this exemplary study of its temporal and depositional context.”

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Typical Cradle of Humankind landscape today. We believe that at specific times in the past, this environment was much wetter and more vegetated than today. Dr Robyn Pickering

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Field photograph of massive flowstone layers from one of the South African hominin caves, with red cave sediments underneath. Robyn Pickering

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Article Source: University of Cape Town news release

The ‘Swiss Army knife of prehistoric tools’ found in Asia suggests homegrown technology

UNIVERSITY OF WASHINGTON—New analysis of artifacts found at a South China archaeological site shows that sophisticated tool technology emerged in East Asia earlier than previously thought.

A study by an international team of researchers, including from the University of Washington, determines that carved stone tools, also known as Levallois cores, were used in Asia 80,000 to 170,000 years ago. Developed in Africa and Western Europe as far back as 300,000 years ago, the cores are a sign of more-advanced toolmaking—the “multi-tool” of the prehistoric world—but, until now, were not believed to have emerged in East Asia until 30,000 to 40,000 years ago.

With the find—and absent human fossils linking the tools to migrating populations—researchers believe people in Asia developed the technology independently, evidence of similar sets of skills evolving throughout different parts of the ancient world.

The study is published online Nov. 19 in Nature.

“It used to be thought that Levallois cores came to China relatively recently with modern humans,” said Ben Marwick, UW associate professor of anthropology and one of the paper’s corresponding authors. “Our work reveals the complexity and adaptability of people there that is equivalent to elsewhere in the world. It shows the diversity of the human experience.”

Levallois-shaped cores—the “Swiss Army knife of prehistoric tools,” Marwick said—were efficient and durable, indispensable to a hunter-gatherer society in which a broken spear point could mean certain death at the claws or jaws of a predator. The cores were named for the Levallois-Perret suburb of Paris, where stone flakes were found in the 1800s.

Featuring a distinctive faceted surface, created through a sequence of steps, Levallois flakes were versatile “blanks,” used to spear, slice, scrape or dig. The knapping process represents a more sophisticated approach to tool manufacturing than the simpler, oval-shaped stones of earlier periods.

The Levallois artifacts examined in this study were excavated from Guanyindong Cave in Guizhou Province in the 1960s and 1970s. Previous research using uranium-series dating estimated a wide age range for the archaeological site—between 50,000 and 240,000 years old—but that earlier technique focused on fossils found away from the stone artifacts, Marwick said. Analyzing the sediments surrounding the artifacts provides more specific clues as to when the artifacts would have been in use.

Marwick and other members of the team, from universities in China and Australia, used optically stimulated luminescence (OSL) to date the artifacts. OSL can establish age by determining when a sediment sample, down to a grain of sand, was last exposed to sunlight—and thus, how long an artifact may have been buried in layers of sediment.

“Dating for this site was challenging because it had been excavated 40 years ago, and the sediment profile was exposed to air and without protection. So trees, plants, animals, insects could disturb the stratigraphy, which may affect the dating results if conventional methods were used for dating,” said Bo Li , an associate professor of archaeology at the University of Wollongong in Australia and one of the paper’s corresponding authors. “To solve this problem we used a new single-grain dating technique recently developed in our OSL lab at the University of Wollongong to date individual mineral grains in the sediment. Luckily we found residual sediment left over by the previous excavations, so that allowed us to take samples for dating.”

The researchers analyzed more than 2,200 artifacts found at Guanyindong Cave, narrowing down the number of Levallois-style stone cores and flakes to 45. Among those believed to be in the older age range, about 130,000 to 180,000 years old, the team also was able to identify the environment in which the tools were used: an open woodland on a rocky landscape, in “a reduced rainforest area compared to today,” the authors note.

In Africa and Europe these kinds of stone tools are often found at archaeological sites starting from 300,000 and 200,000 years ago. They are known as Mode III technology, part of a broad evolutionary sequence that was preceded by hand-axe technology (Mode II) and followed by blade tool technology (Mode IV). Archaeologists thought that Mode IV technologies arrived in China by migration from the West, but these new finds suggest they could have been locally invented. At the time people were making tools in Guanyindong Cave, the Denisovans—ancestors to Homo sapiens and relative contemporaries to Neanderthals elsewhere in the world—roamed East Asia. But while hundreds of fossils of archaic humans and related artifacts, dating as far back as more than 3 million years ago, have been found in Africa and Europe, the archaeological record in East Asia is sparser.

That’s partly why a stereotype exists, that ancient peoples in the region were behind in terms of technological development, Marwick said.

“Our work shows that ancient people there were just as capable of innovation as anywhere else. Technological innovations in East Asia can be homegrown, and don’t always walk in from the West,” he said.

The independent emergence of the Levallois technique at different times and places in the world is not unique in terms of prehistoric innovations. Pyramid construction, for one, appeared in at least three separate societies: the Egyptians, the Aztecs and the Mayans. Boatbuilding began specific to geography and reliant on a community’s available materials. And writing, of course, developed in various forms with distinct alphabets and characters.

In the evolution of tools, Levallois cores represent something of a middle stage. Subsequent manufacturing processes yielded more-refined blades made of rocks and minerals that were more resistant to flaking, and composites that, for example, combined a spear point with blades along the edge. The appearance of blades later in time indicates a further increase in the complexity and the number of steps required to make the tools.

“The appearance of the Levallois strategy represents a big increase in the complexity of technology because there are so many steps that have to work in order to get the final product, compared to previous technologies,” Marwick said.

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These artifacts found in China are among the nearly four dozen that reflect the Levallois technique of toolmaking. In a paper published Nov. 19 in Nature, researchers date these artifacts to between 80,000 and 170,000 years ago. Marwick et al.

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The map shows where Levallois artifacts have been found. The oldest, dating to 337,000 years ago, have been found in Europe and Africa. The star on the map marks the site of Guanyindong Cave, where new research published in the journal Nature shows that this technology was used 80,000 to 170,000 years ago in Asia, much earlier than previously thought. Marwick et al.

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Article Source: University of Washington news release

Other authors on the paper were Yue Hu and Xue Rui of the University of Wollongong; Jia-Fu Zhang of Peking University in China; Ya-Mei Hou, Jian-Ping Yue and Wei-Wen Huang of the Chinese Academy of Sciences; and Wen-Rong Chen of the Bureau of Cultural Relics Protection in Guizhou Province, China.

New virtual reconstruction of a Neanderthal thorax suggests another breathing mechanism

UNIVERSITY OF THE BASQUE COUNTRY—Neanderthals were hunter-gatherers who inhabited western Eurasia for more than 200 thousand years during glacial as well as interglacial periods until they became extinct around 40 thousand years ago. While some of the anatomical regions of these extinct humans are well known, others, such as the vertebral column and the ribs, are less well known because these elements are more fragile and not well preserved in the fossil record. In 1983 a partial Neanderthal skeleton (known officially as Kebara 2, and nicknamed “Moshe”) belonging to a young male Neanderthal individual who died some 60,000 years ago was found in the Kebara site (Mount Carmel, Israel). While this skeleton does not preserve the cranium because some time after burial the cranium was removed, probably as a consequence of a funerary ritual. However, all the vertebrae and ribs are preserved, and so are other fragile anatomical regions, such as the pelvis or the hyoid bone (a bone in the neck to which some of the tongue muscles are attached). So it is the skeleton that preserves the most complete thorax in the fossil record.

New statistical and virtual reconstruction methods have enabled the researchers to extract new information, which has just been published in the prestigious journal Nature Communications.

For over 150 years, Neanderthal remains have been found at many sites in Europe and Western Asia (including the Middle East), and the thorax morphology of this human species has been a subject of debate since 1856, when the first ribs belonging to this human group were found. Over the past decade, virtual reconstructions have become a new tool that is increasingly being used in fossil study. This methodology is particularly useful with fragile fossils, such as the vertebra and ribs that form the thorax. Nearly two years ago, the same research team created a reconstruction of the spine of this Neanderthal individual; it displays the preserved spine of Kebara 2 showing less pronounced curves in these humans when compared with Homo sapiens. The team’s paper, published in the book “Human Paleontology and Prehistory,” pointed to a straighter spine than that of modern humans.

For this virtual model of the thorax, researchers used both direct observations of the Kebara 2 skeleton, currently housed at Tel Aviv University, and medical CT (computerized axial tomography) scans of the vertebrae, ribs and pelvic bones. Once all the anatomical elements had been assembled, the virtual reconstruction was done by means of 3D software specifically designed for this purpose. “This was meticulous work,” said Alon Barash of Bar Ilan University in Israel. “We had to scan each vertebra and all of the rib fragments individually and then reassemble them in virtual 3D.”

“In the reconstruction process, it was necessary to virtually ‘cut’ and realign some of the parts that displayed deformation, and mirror-image the ribs that had been best preserved in order to substitute the poorly preserved ones on the other side,” said Asier Gómez-Olivencia, an Ikerbasque research fellow at the University of the Basque Country.

“The differences between the thorax of a Neanderthal and of a modern human are striking,” said Daniel García-Martínez and Markus Bastir, researchers at the National Museum of Natural Sciences (MNCN-CSIC) and co-authors of the work. “The Neanderthal spine is located more inside the thorax with respect to the ribs, which provides more stability. The thorax is also wider in its lower part,” added Mikel Arlegi (UPV/EHU).

“The wider lower thorax of Neanderthals and the more horizontal orientation of the ribs, as shown in its reconstruction, suggest that Neanderthals relied more on the diaphragm for breathing,” said Ella Been of the Ono Academic College. “Modern humans rely on both the diaphragm and on the expansion of the rib cage. Here we can see how new technologies and methodologies in the study of fossil remains are providing new information to understand extinct species.”

This new information is consistent with the recent works on the larger lung capacity of Neanderthals published by two of the co-authors of this study, Markus Bastir and Daniel García-Martínez (Virtual Anthropology Laboratory of the MNCN), in which they support the presence of greater lung capacity in the Neanderthals.).

Patricia Kramer of the University of Washington sums it all up thus: “This is the culmination of 15 years of research into the Neanderthal thorax; we hope that future genetic analyses will provide additional clues about the respiratory physiology of the Neanderthals”.

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Image of the reconstruction of the thorax of Kebara 2. Scale = 5 cm. A. Gómez-Olivencia, A. Barash and E. Been

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Article Source: University of the Basque Country news release.

This work was conducted by an international group of researchers from Ikerbasque, UPV/EHU-University of the Basque Country, the Université de Bordeaux, Ono Academic College, Tel Aviv University, University of Washington, Bar Ilan University and the National Museum of Natural Sciences (NMNC) in Madrid.

Climate change likely caused migration, demise of ancient Indus Valley civilization

WOODS HOLE OCEANOGRAPHIC INSTITUTION—More than 4,000 years ago, the Harappa culture thrived in the Indus River Valley of what is now modern Pakistan and northwestern India, where they built sophisticated cities, invented sewage systems that predated ancient Rome’s, and engaged in long-distance trade with settlements in Mesopotamia. Yet by 1800 BCE, this advanced culture had abandoned their cities, moving instead to smaller villages in the Himalayan foothills. A new study from the Woods Hole Oceanographic Institution (WHOI) found evidence that climate change likely drove the Harappans to resettle far away from the floodplains of the Indus.

Beginning in roughly 2500 BCE, a shift in temperatures and weather patterns over the Indus valley caused summer monsoon rains to gradually dry up, making agriculture difficult or impossible near Harappan cities, says Liviu Giosan, a geologist at WHOI and lead author on the paper that published Nov. 13, 2018, in the journal Climate of the Past.

“Although fickle summer monsoons made agriculture difficult along the Indus, up in the foothills, moisture and rain would come more regularly,” Giosan says. “As winter storms from the Mediterranean hit the Himalayas, they created rain on the Pakistan side, and fed little streams there. Compared to the floods from monsoons that the Harappans were used to seeing in the Indus, it would have been relatively little water, but at least it would have been reliable.”

Evidence for this shift in seasonal rainfall—and the Harappans’ switch from relying on Indus floods to rains near the Himalaya in order to water crops—is difficult to find in soil samples. That’s why Giosan and his team focused on sediments from the ocean floor off Pakistan’s coast. After taking core samples at several sites in the Arabian Sea, he and his group examined the shells of single-celled plankton called foraminifera (or “forams”) that they found in the sediments, helping them understand which ones thrived in the summer, and which in winter.

Once he and the team identified the season based on the forams’ fossil remains, they were able to then focus on deeper clues to the region’s climate: paleo-DNA, fragments of ancient genetic material preserved in the sediments.

“The seafloor near the mouth of the Indus is a very low-oxygen environment, so whatever grows and dies in the water is very well preserved in the sediment,” says Giosan. “You can basically get fragments of DNA of nearly anything that’s lived there.”

During winter monsoons, he notes, strong winds bring nutrients from the deeper ocean to the surface, feeding a surge in plant and animal life. Likewise, weaker winds other times of year provide fewer nutrients, causing slightly less productivity in the waters offshore.

“The value of this approach is that it gives you a picture of the past biodiversity that you’d miss by relying on skeletal remains or a fossil record. And because we can sequence billions of DNA molecules in parallel, it gives a very high-resolution picture of how the ecosystem changed over time,” adds William Orsi, paleontologist and geobiologist at Ludwig Maximilian University of Munich, who collaborated with Giosan on the work.

Sure enough, based on evidence from the DNA, the pair found that winter monsoons seemed to become stronger—and summer monsoons weaker—towards the later years of the Harappan civilization, corresponding with the move from cities to villages.

“We don’t know whether Harappan caravans moved toward the foothills in a matter of months or this massive migration took place over centuries. What we do know is that when it concluded, their urban way of life ended,” Giosan says.

The rains in the foothills seem to have been enough to hold the rural Harappans over for the next millennium, but even those would eventually dry up, likely contributing to their ultimate demise.

“We can’t say that they disappeared entirely due to climate—at the same time, the Indo-Aryan culture was arriving in the region with Iron Age tools and horses and carts. But it’s very likely that the winter monsoon played a role,” Giosan says.

The big surprise of the research, Giosan notes, is how far-flung the roots of that climate change may have been. At the time, a “new ice age” was settling in, forcing colder air down from the Arctic into the Atlantic and northern Europe. That in turn pushed storms down into the Mediterranean, leading to an upswing in winter monsoons over the Indus valley.

“It’s remarkable, and there’s a powerful lesson for today,” he notes. “If you look at Syria and Africa, the migration out of those areas has some roots in climate change. This is just the beginning—sea level rise due to climate change can lead to huge migrations from low lying regions like Bangladesh, or from hurricane-prone regions in the southern U.S. Back then, the Harappans could cope with change by moving, but today, you’ll run into all sorts of borders. Political and social convulsions can then follow.”

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The ancient Indus Valley. Avantiputra7, Wikimedia Commons

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The archaeological remains of Mohenjodaro, the great ancient city of the Harappan civilization. Usman.pg, Wikimedia Commons

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Article Source: Woods Hole Oceanographic Institution news release

Also collaborating on the study was Ann G. Dunlea, Samuel E. Munoz, Jeffrey. P. Donnelly, and Valier Galy of WHOI; William D. Orsi of Ludwig-Maximilians-Universität Munchen; Marco Coolen and Cornelia Wuchter of Curtin University in Australia; Kaustubh Thirumalai of Brown University; Peter D. Clift of Louisiana State University; and Dorian Q. Fuller of University College, London.

Experts find that stone tools connected communities

UNIVERSITY OF THE WITWATERSRAND—The tools – mainly blades and backed knives from the Howiesons Poort – were found in various layers in the Klipdrift Shelter, in the southern Cape in South Africa. They were examined by a group of lithic experts, who found distinct similarities to tools from sites in South Africa’s Western Cape, over 300km away, in particular with the Diepkloof Rock Shelter site.

“While regional specificities in the tools from the various sites exist, the similarities of Klipdrift Shelter with the site of Diepkloof Rock Shelter are astonishing,” says Dr Katja Douze, the corresponding author of the study that was published in PLOS ONE on November 7. Douze is a researcher at the laboratory of Archaeology and Populations in Africa at the University of Geneva, Switzerland. Douze was a post-doctoral fellow at the Center of Excellence in Palaeosciences at the Evolutionary Studies Institute, at University of the Witwatersrand (Wits), at the time of the study. She led the analysis together with Dr Anne Delagnes, Research Director at the French National Center for Research (CNRS) and director of the laboratory PACEA, at the University of Bordeaux, and with Dr Sarah Wurz, Associate professor at the School of Geography, Archaeology and Environmental Sciences, University of the Witwatersrand and also associated with the DST/NRF SARChI Chair in The Origins of Modern Human Behaviour and the SapienCE – Centre for Early Sapiens Behaviour (SFF CoE).

The team, under the leadership of Professor Christopher Henshilwood from Wits University and the University of Bergen’s SapienCE Centre for Early Sapiens Behaviour, examined thousands of stone tools that were excavated from seven layers that represent a time period of between 66 000 years ago and 59 000 years ago, to establish the differences in stone tool design over time. They then also compared the stone tools to various other sites in Howiesons Poort.

“The site of Klipdfrift Shelter is one of the few containing a long archaeological sequence that provides data on cultural changes over time during the Howiesons Poort,” says Douze. “This makes it perfect to study the change in culture over time.”

However, what was even more exciting for the researchers was the fact that for the first time they could show closely networked interaction between distant communities through the way they designed stone tools.

“There was an almost perfect match between the tools from the Klipdrift and Diepkloof shelters,” says Douze. “This shows us that there was regular interaction between these two communities.”

“This is the first time that we can draw such a parallel between different sites based on robust sets of data, and show that there was mobility between the two sites. This is unique for the Middle Stone Age,” says Douze.

The Middle Stone Age in Africa stretches from 350 000 years ago to 25 000 years ago and is a key period for understanding the development of the first Homo sapiens, their behavioral changes through time and their movements in-and-out of Africa.

Named after Howieson’s Poort Shelter archeological site near Grahamstown in South Africa, the Howiesons Poort is a specific techno-culture within the Middle Stone Age that evolves in southern Africa after 100 000 years ago at the Diepkloof Shelter, but between 66 000 – 59 000 years at most other Howiesons Poort sites. The characteristics of the Howiesons Poort are strongly distinctive from other Middle Stone Age industries as it is characterized by the production of small blades and backed tools, used as hunting armatures as much as for cutting flesh, while other MSA industries show flake, large blade and point productions.

The tools found in the deeper layers of the Klipdrift Shelter that represent the earlier phases of the Howiesons Poort were found to be made from heat-treated silcrete, while those from later phases were made from less homogeneous rocks such as quartz and quartzite. This change happens together with changes in tool production strategies. “The changes over time seems to reflect cultural changes, rather than immediate alterations forced on the designers by changes in climate”, says Douze.

“Our preconceived idea of prehistoric groups is that they just struggled to survive, but in fact they were very adaptable to environmental circumstances. There seem to be no synchrony between modification in design choices and environmental changes. However, the aridification of the area over time might have led to a very gradual change that led to the end of the Howiesons Poort.”

The team also attempted to establish why and how the Howiesons Poort ended, and to see whether it came to a sudden, or gradual end.

“The decline of the Howiesons Poort at Klipdrift Shelter shows a gradual and complex pattern of changes, from which the first “symptoms” can be observed much earlier than the final abandonment of typical Howiesons Poort technology and toolkits,” says Douze.

“This does not support a catastrophic scenario involving alarming demographic drops or massive population replacements. The fact that a similar pattern of gradual change has been described for at least three other southern African Howiesons Poort sites (Rose Cottage Cave, Diepkloof Rock Shelter and Klasies River main site), further ascertains convergent evolutions in cultural trajectories rather than isolated groups promptly reacting to locally determined pressures.”

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The location of the Klipdrift Shelter and other South African Howiesons Poort sites. Katja Douze

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Overview of the Klipdrift Complex from sea. Magnus Haaland

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Examples of Howiesons Poort stone tools from Klipdrift. Anne Delagnes and Gauthier Devilder

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[See the article, Exploring the Roots of Modern Humanity, a previously published premium article (now free) that documents a Popular Archaeology interview of renowned archaeologist Christopher Henshilwood about the beginnings of behaviorally modern humans in South Africa.]

Article Source: University of the Witwatersrand news release

Genetic Research Reveals Revelatory New Insights on the Peopling of the Americas

AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE—A comprehensive, hemisphere-spanning study of ancient DNA suggests a highly complex peopling of the American continents – one that cannot be explained by simple models or patterns of dispersal. The study involved an analysis of ancient American genomes unearthed in locations spanning from Alaska to Patagonia. While there has been much focus on the timing and number of initial migrations into North and South America, less attention has been paid to the subsequent expansion throughout the American continents. Previous genomic studies have suggested that the first American populations diverged from their Siberian and East Asian ancestors nearly 25,000 years ago, and subsequently split into distinct North American and South American populations about 10,000 years later. However, the expansion of the first Americans remains a contentious topic and has been difficult to understand from analysis of present-day populations. Víctor Moreno-Mayar and colleagues sequenced the genomes of 15 ancient Americans from locations spanning the Americas, and six of which were more than 10,000 years old. The results reveal a complex picture of population expansion and diversification. According to Moreno-Mayar et al., people spread out rapidly, yet unevenly, throughout the Americas, and diversified into multiple populations, some of which were unknown before this analysis -visible only in the genetic record. Interestingly, the authors identified the presence of a Late Pleistocene (about 11,700 BP) population with Australasian ancestry evident only in South America, which left no apparent genetic traces in North America. In addition, the authors find evidence of a smaller Mesoamerican-related population expansion evident through a geographically widespread admixture of genetic material. While the study’s results fill some gaps in our understanding of early Americans and reveal a complex population history, the authors note that the peopling of the Americas is likely more complicated still, as evidenced by the identification of unknown groups here.

Clovis, Genetic Exchanges, and Population Turnover in Central and South America

HARVARD MEDICAL SCHOOL—The international team of researchers revealed unexpected details about the peopling of Central and South America by studying the first high-quality ancient DNA data from those regions.

The findings include two previously unknown genetic exchanges between North and South America, one of which represents a continent-wide population turnover.

The results suggest that the people who spread the Clovis culture, the first widespread archaeological culture of North America, had a major demographic impact further south than previously appreciated.

The authors analyzed genome-wide data from 49 individuals from Central and South America, some as old as 11,000 years. Previously, the only genomes that had been reported from this region and that provided sufficient quality data to analyze were less than 1,000 years old.

By comparing ancient and modern genomes from the Americas and other parts of the globe, the researchers were able to obtain qualitatively new insights into the early history of Central and South America.

Published in the journal Cell, the study was led by researchers at Harvard Medical School; the Howard Hughes Medical Institute; the Max Planck Institute for the Science of Human History; the University of California, Santa Cruz; Pennsylvania State University; the University of New Mexico; the University of São Paulo and other institutions in Argentina, Australia, Belize, Brazil, Chile, the European Union, Peru and the United States.

The researchers obtained official permits to excavate and conduct analysis on ancient human remains and consulted with local governmental agencies and indigenous communities.

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The exterior of the rock shelter site of Lapa do Santo in Brazil. André Strauss

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Excavation in progress at the rock shelter site of Lapa do Santo in Brazil, where an individual dating to approximately~9,600 years ago was found. AndréStrauss

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This individual from the site of Los Rieles in Chile is the oldest in the study at ~11,000 years ago. Bernardita Ladrón de Guevara, 2008

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Graphic showing the geographic movement of populations discussed in the study. Graphic: Michelle O’Reilly; Posth, Nakatsukaet al. 2018. Reconstructing the Deep Population History of Central and South America. Cell.

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Clovis link in the oldest Central and South Americans

A distinctive DNA type associated with the Clovis culture was found in Chile, Brazil and Belize 11,000 to 9,000 years ago.

“A key discovery was that a Clovis culture-associated individual from North America dating to around 12,800 years ago shares distinctive ancestry with the oldest Chilean, Brazilian and Belizean individuals,” said co-lead author Cosimo Posth of the Max Planck Institute for the Science of Human History. “This supports the hypothesis that the expansion of people who spread the Clovis culture in North America also reached Central and South America.”

However, the Clovis culture-associated lineage is missing in present-day South Americans and in ancient samples that are less than 9,000 years old.

“This is our second key discovery,” said co-senior author David Reich, professor of genetics at Harvard Medical School and a Howard Hughes Medical Institute investigator. “We have shown that there was a continent-wide population replacement that began at least 9,000 years ago.”

After the population replacement, there was striking genetic continuity between ancient individuals dating to up to 9,000 years ago and modern people from multiple South American regions. This contrasts with West Eurasia and Africa, where there are few places with such long-standing continuity.

California Channel Island-associated ancestry in the Andes

The second previously unknown spread of people revealed itself in an analysis showing that ancient Californians from the Channel Islands have a distinctive shared ancestry with groups that became widespread in the southern Peruvian Andes by at least 4,200 years ago.

The researchers say this is unlikely to reflect population spread specifically from the Channel Islands into South America. Instead, they hypothesize that the connection between these regions is the result of expansions of people that occurred thousands of years earlier, and that such ancestry became more widespread in the Andes after subsequent events within South America.

“It could be that this ancestry arrived in South America thousands of years before and we simply don’t have earlier individuals showing it,” said Nathan Nakatsuka, a research assistant in the Reich lab at Harvard Medical School and co-lead author of the study. “There is archaeological evidence that the population in the Central Andes area greatly expanded after around 5,000 years ago. Spreads of particular subgroups during these events may be why we detect this ancestry afterward.”

The promise of ancient DNA research in the Americas

The researchers emphasize that their study gives only a glimpse of the discoveries that may come through future work.

To learn about the initial movements of people into Central and South America, they say, it would be necessary to obtain ancient DNA from individuals dating to before 11,000 years ago.

Even for the period between 11,000 and 3,000 years ago that this study focused on, the picture is far from complete.

“We lacked ancient data from Amazonia, northern South America and the Caribbean, and thus cannot determine how individuals in these regions relate to the ones we analyzed,” said Reich. “Filling in these gaps should be a priority for future work.”

“We are excited about the potential of research in this area,” said co-senior author Johannes Krause of the Max Planck Institute for the Science of Human History. “With future regionally-focused studies with large sample sizes, we could realize the potential of ancient DNA to reveal how the human diversity of this region came to be the way it is today.”

An Ancient Child’s Tooth and Early Alaskan Inhabitants

UNIVERSITY OF ALASKA FAIRBANKS—Recent research on a newly rediscovered 9,000-year-old child’s tooth has reshaped our understanding of Alaska’s ancient people, their genetic background and their diets.

The tooth is only the second known remnant of a population of early migrants known as Ancient Beringians. Combined with previous University of Alaska Fairbanks research, the find indicates that Ancient Beringians remained in Alaska for thousands of years after first migrating across the Bering Land Bridge that connected eastern Asia and Alaska.

Investigation of the tooth, conducted by researchers at UAF and the National Park Service in Alaska, was part of a larger study documented by a paper published Nov. 8 in the journal Science. That research included genetic analysis of 15 diverse bone samples from sites across North and South America, revealing a broad picture of how the Americas were populated by its earliest peoples.

The Alaska tooth had been largely forgotten since it was excavated in 1949 by Danish archaeologists from the Trail Creek Caves site on Alaska’s Seward Peninsula. For almost 70 years it remained in storage in Copenhagen, Denmark, until it was found in 2016 by Jeff Rasic, a Fairbanks-based NPS archaeologist who was conducting new analyses of this old collection.

Radiocarbon dating determined the tooth, which belonged to a 1½-year-old child, is by far the oldest human specimen in the North American Arctic—more than twice as old as the next oldest remains. Genomic testing connected the tooth to the Ancient Beringian lineage. The only other trace of that population was discovered in 2013 by a team led by UAF associate professor Ben Potter at a site in Alaska’s Interior.

When looked at together, those two sites—separated by about 400 miles and 2,500 years—show that Ancient Beringians were present across the vast expanse of Alaska for millennia.

“This one small tooth is a treasure trove of information about Alaska’s early populations, not only their genetic affinities but also their movements, interactions with other people and diet,” said Rasic.

Researchers worked with tribal officials from the Seward Peninsula village of Deering to coordinate efforts to study the tooth.

Analysis at UAF’s Alaska Stable Isotope Facility also revealed surprising details about the lives of the child and, by proxy, the mother who fed the child. By studying chemical signatures preserved in the tooth, ASIF Director Matthew Wooller was able to analyze their diet.

“The child’s food sources were entirely terrestrial, a sharp contrast with other sites that indicate inclusion of anadromous fish and marine resources.” Wooller said.

That land-based diet is a surprise—during the time the child lived on the Seward Peninsula, sea levels had risen to nearly modern levels. Those rising waters had cut off the Bering Land Bridge and surrounded most of the peninsula, making marine resources accessible.

Further isotope results and modeling, which were conducted by Rasic, Wooller and Clement Bataille from the University of Ottawa, also determined the family resided in the region surrounding the caves, and were not migrants from elsewhere in Alaska or Siberia.

“The combination of isotope signatures found in the tooth is pretty specific to the interior Seward Peninsula, making a local origin for the family very probable,” Bataille said.

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An aerial view of the Trail Creek Caves site on Alaska’s Seward Peninsula. Analysis of a 9,000-year-old tooth from the site has broadened understanding of Alaska’s early inhabitants. NPS photo by Jeff Rasic

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Artifact collections from Helge Larsen’s 1949-50 excavations from the Trail Creek Caves site, housed at the Danish National Museum in Copenhagen, Denmark. NPS photo by Jeff Rasic

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Early Settlement and Survival in the Andean Highlands

UNIVERSITY OF CHICAGO MEDICAL CENTER—A multi-center study of the genetic remains of people who settled thousands of years ago in the Andes Mountains of South America reveals a complex picture of human adaptation from early settlement, to a split about 9,000 years ago between high and lowland populations, to the devastating exposure to European disease in the 16th-century colonial period.

Led by Anna Di Rienzo, PhD, and John Lindo, PhD, JD, from the University of Chicago; Mark Aldenderfer, PhD, from the University of California, Merced; and Ricardo Verdugo from the University of Chile, the researchers used newly available samples of DNA from seven whole genomes to study how ancient Andean people—including groups that clustered around Lake Titicaca in Peru and Bolivia, 12,000 feet above sea level—adapted to their environment over the centuries.

In the journal Science Advances, they compared their seven historical genomes to 64 modern-day genomes from a current highland Andean population, the agropastoral Aymara of Bolivia, and the lowland hunter-gatherer Huilliche-Pehuenche in coastal Chile.

The goals were (1) to date the initial migration to the Andean highlands, (2) to identify the genetic adaptations to the high-altitude environment that allowed that settlement, (3) to estimate the impact of the European contact starting in the 1530s that caused the near annihilation of many lowland communities of South America.

“We have very ancient samples from the high Andes,” said Di Rienzo. “Those early settlers have the closest affinity to the people who now live in that area. This is a harsh, cold, resource-poor environment, with low oxygen levels, but people there adapted to that habitat and the agrarian lifestyle.”

The study, “The Genetic prehistory of the Andean highlands 7,000 years BP through European contact,” uncovered several unexpected features.

The researchers found that highland Andeans experienced much smaller than expected population declines following contact with European explorers who first came to South America in the 1530s. In the lowlands, demographic modeling and historical records infer that up to 90 percent of residents may had been wiped out after the arrival of Europeans. But the people living in the upper Andes had only a 27-percent population reduction.

Even though the highlanders lived in altitudes above 8,000 feet, which meant reduced oxygen, frequent frigid temperatures and intense ultra-violet radiation, they did not develop the responses to hypoxia seen in natives of other high-altitude settings, such as Tibet.

The Andeans may have adapted to high altitude hypoxia “in a different way, via cardiovascular modifications,” the researchers suggest. They found evidence of alterations in a gene called DST, which is associated with the formation of cardiac muscle. Andean highlanders tend to have enlarged right ventricles. This may have improved oxygen intake, enhancing blood flow to the lungs.

But the strongest adaptation signal the researchers found was in a gene called MGAM (maltase-glucoamylase) an intestinal enzyme. It plays an important role in the digestion of starchy foods such as potatoes—a food native to the Andes. A recent study suggests that the potato may have been domesticated in the region at least 5,000 years ago. Positive selection on the MGAM gene, the authors note, “may represent an adaptive response to greater reliance upon starchy domesticates.”

The early presence of this variant in Andean peoples suggests “a significant shift in diet from one that was likely more meat based to one more plant based,” said UC Merced’s Aldenderfer, an anthropologist. “The timing of the appearance of the variant is quite consistent with what we know of the paleo-ethno-botanical record in the highlands.”

Although Andean settlers consumed a high-starch diet after they started to farm, their genomes did not develop additional copies of the starch related amylase gene, commonly seen in European farming populations.

A comparison of the ancient genomes with their living descendants also revealed selection for immune-related genes soon after the arrival of Europeans, suggesting that Andeans who survived may have had an advantage with regard to the newly introduced European pathogens.

“Contact with Europeans had a devastating impact on South American populations, such as the introduction of disease, war, and social disruption,” explained Lindo. “By focusing on the period before that, we were able to distinguish environmental adaptations from adaptations that stemmed from historical events.”

“In our paper,” said Aldenderfer, “there was none of this prioritization of genes at the expense of archaeological data. We worked back and forth, genetics and archaeology, to create a narrative consistent with all of the data at hand.”

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Location of ancient samples near Lake Titicaca, elevation 3812 meters, in what is now Peru and Bolivia. Authors of the study

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Entry into the Americas 20 ka ago. High/low altitude split 8750 years. European contact 1532 AD. Study authors

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The Oldest Natural Mummy, Paleoamericans, and Australasians

ST JOHN’S COLLEGE, UNIVERSITY OF CAMBRIDGE—A legal battle over a 10,600 year old ancient skeleton – called the ‘Spirit Cave Mummy’ – has ended after advanced DNA sequencing found it was related to a Native American tribe.

The revelation was published in Science as part of the wide-ranging international study that genetically analyzed the DNA of a series of famous and controversial ancient remains across North and South America, including Spirit Cave, the Lovelock skeletons, the Lagoa Santa remains, an Inca mummy, and the oldest remains in Chilean Patagonia. This study also looked at the second oldest human remains from Trail Creek Cave in Alaska – the 9,000 year old milk tooth from a young girl [related previously above].

The team of academics not only discovered that the Spirit Cave remains – the world’s oldest natural mummy – was a Native American but they were able to dismiss a longstanding theory that a group called Paleoamericans existed in North America before Native Americans.

The ground-breaking research also discovered clues of a puzzling Australasian genetic signal in the 10,400 year old Lagoa Santa remains [as mentioned previously above] from Brazil, revealing a previously unknown group of early South Americans – but the Australasian link left no genetic trace in North America. It was described by one of the scientists as ‘extraordinary evidence of an extraordinary chapter in human history’.

Professor Eske Willeslev, who holds positions both at St John’s College, University of Cambridge, and the University of Copenhagen, and led the study, said: “Spirit Cave and Lagoa Santa were very controversial because they were identified as so-called ‘Paleoamericans’ based on craniometry – it was determined that the shape of their skulls was different to current day Native Americans. Our study proves that Spirit Cave and Lagoa Santa were actually genetically closer to contemporary Native Americans than to any other ancient or contemporary group sequenced to date.”

The Lagoa Santa remains were retrieved by Danish explorer Peter W. Lund in the 19th century and his work led to this ‘Paleoamerican hypothesis’ based on cranial morphology that theorized the famous group of skeletons could not be Native Americans. But this new study disproves that theory and the findings were launched under embargo by Professor Willeslev with representatives from the Brazilian National Museum in Rio on Tuesday, November 6 2018.

He added: “Looking at the bumps and shapes of a head does not help you understand the true genetic ancestry of a population – we have proved that you can have people who look very different but are closely related.”

The scientific and cultural significance of the Spirit Cave remains, which were found in 1940 in a small rocky alcove in the Great Basin Desert, was not properly understood for 50 years. The preserved remains of the man in his forties were initially believed to be between 1,500 and 2000 years old, but during the 1990s new textile and hair testing dated the skeleton at 10,600 years old.

The Fallon Paiute-Shoshone Tribe, a group of Native Americans based in Nevada near Spirit Cave, claimed cultural affiliation with the skeleton and requested immediate repatriation of the remains under the Native American Graves Protection and Repatriation Act.

The request was refused because the ancestry was disputed, the tribe sued the federal government and the lawsuit pitted tribal leaders against anthropologists, who argued the remains provided invaluable insights into North America’s earliest inhabitants and should continue to be displayed in a museum.

The deadlock continued for 20 years until the tribe agreed that Professor Willeslev could carry out genome sequencing on DNA extracted from the Spirit Cave for the first time.

Professor Willeslev said: “I assured the tribe that my group would not do the DNA testing unless they gave permission and it was agreed that if Spirit Cave was genetically a Native American the mummy would be repatriated to the tribe.”

The team painstakingly extracted DNA from the petrus bone from the inside of the skull, proving that the skeleton was an ancestor of present day Native Americans. Spirit Cave was returned to the tribe in 2016 and there was a private reburial ceremony earlier this year that Professor Willeslev attended and details have just been released.

The geneticist explained: “What became very clear to me was that this was a deeply emotional and deeply cultural event. The tribe have real feelings for Spirit Cave, which as a European it can be hard to understand but for us it would very much be like burying our mother, father, sister or brother.

“We can all imagine what it would be like if our father or mother was put in an exhibition and they had that same feeling for Spirit Cave. It has been a privilege to work with them.”

The tribe was kept informed throughout the two year project and two members visited the lab in Copenhagen to meet the scientists and they were present when all of the DNA sampling was taken.

According to a statement from the Fallon Paiute-Shoshone Tribe: “The Tribe has had a lot of experience with members of the scientific community, mostly negative. However, there are a handful of scientists that seemed to understand the Tribe’s perspective and Eske Willerslev was one of them.

“He took the time to acquaint himself with the Tribe, kept us well-informed of the process, and was available to answer our questions. His new study confirms what we have always known from our oral tradition and other evidence – that the man taken from his final resting place in Spirit Cave is our Native American ancestor.”

The genome of the Spirit Cave skeleton has wider significance because it not only settled the legal and cultural dispute between the tribe and the Government, it also helped reveal how ancient humans moved and settled across the Americas. The scientists were able to track the movement of populations from Alaska to as far south as Patagonia. They often separated from each other and took their chances traveling in small pockets of isolated groups.

Dr David Meltzer, from the Department of Anthropology, Southern Methodist University, Dallas, said: “A striking thing about the analysis of Spirit Cave and Lagoa Santa is their close genetic similarity which implies their ancestral population traveled through the continent at astonishing speed. That’s something we’ve suspected due to the archaeological findings, but it’s fascinating to have it confirmed by the genetics. These findings imply that the first peoples were highly skilled at moving rapidly across an utterly unfamiliar and empty landscape. They had a whole continent to themselves and they were traveling great distances at breath-taking speed.”

The study also revealed surprising traces of Australasian ancestry in ancient South American Native Americans but no Australasian genetic link was found in North American Native Americans. Dr Victor Moreno-Mayar, from the Centre for GeoGenetics, University of Copenhagen and first author of the study, said: “We discovered the Australasian signal was absent in Native Americans prior to the Spirit Cave and Lagoa Santa population split which means groups carrying this genetic signal were either already present in South America when Native Americans reached the region, or Australasian groups arrived later. That this signal has not been previously documented in North America implies that an earlier group possessing it had disappeared or a later arriving group passed through North America without leaving any genetic trace.”

Dr Peter de Barros Damgaard, from the Centre for GeoGenetics, University of Copenhagen, explained why scientists remain puzzled but optimistic about the Australasian ancestry signal in South America. He explained: “If we assume that the migratory route that brought this Australasian ancestry to South America went through North America, either the carriers of the genetic signal came in as a structured population and went straight to South America where they later mixed with new incoming groups, or they entered later. At the moment we cannot resolve which of these might be correct, leaving us facing extraordinary evidence of an extraordinary chapter in human history! But we will solve this puzzle.”

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Skulls and other human remains from P.W. Lund’s Collection from Lagoa Santa, Brazil kept in the Natural History Museum of Denmark. Natural History Museum of Denmark

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Article Sources: AAAS Science Advances, Harvard Medical School, University of Alaska Fairbanks, and University of Chicago Medical Center. and St. John’s College news releases

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If you liked this article, you may like The Girl in the Cave, a free premium article previously published in Popular Archaeology about the spectacular discovery of the remains of an ancient girl within a submerged cave in Mexico.

Quantitative 3D analysis of bone tools sheds light on ancient manufacture and use

PLOS—Quantitative three-dimensional analysis of bone wear patterns can provide insight into the manufacture and use of early human tools, according to a study by Naomi Martisius of the University of California at Davis and colleagues, published November 7 in the open-access journal PLOS ONE.

Humans have been using bone tools for at least 2 million years, and by approximately 100 thousand years ago, were manufacturing them with formal processes such as grinding and scraping. Ancient bone tools carry marks of their manufacture and use, which can provide information about the group of people that made the tools and the specific uses to which tools were put. Microscopy has been used to study these marks, but the study of use-wear on bone tools requires a comparative body of quantitative examples of wear over time and contact with different materials, to ensure that these studies are replicable. In the current study, the authors sought to determine the basics of use-wear formation over time by taking incremental molds of bone specimens subjected to a controlled, mechanical experiment.

The authors initially shaped bone with sandstone or flint, or left it unshaped, and then used it to work fresh skin, leather, or bark, all while taking sequential surface scans using confocal microscopy, to generate three-dimensional data for a quantitative Bayesian analysis. While individual samples of bone varied in both texture and structure, they found that duration of use was the largest and most unequivocal determinant affecting the surface of the bone. Fresh skin was the most abrasive of the three materials, and the degree of wear correlated with duration of use for working skin.

Further refinement of the specific methodological techniques may be needed to fully investigate correlations that link tool shaping and target material to observed wear patterns. However, the study provides a proof of principle for application of quantitative measures to bone wear analysis. The novel technique provides a possible alternative to current methods of bone wear analysis, which are largely qualitative and dependent on expert interpretation.

Martisius adds: “If we want to understand how ancient humans used bone tools, we need to understand what the traces left on the tools mean. We tested manufacturing and use variables over time using a quantitative method for looking at these traces, and by extension, at human behavior”

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Material wear on bone over time. Martisius et al., 2018

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Article Source: A PLOS ONE news release

*Martisius NL, Sidéra I, Grote MN, Steele TE, McPherron SP, Schulz-Kornas E (2018) Time wears on: Assessing how bone wears using 3D surface texture analysis. PLoS ONE 13(11): e0206078. https://doi.org/10.1371/journal.pone.0206078

Skeletal abnormalities in Pleistocene people

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES—A study* finds that developmental anomalies in fossil individuals from the Pleistocene occurred at higher-than-expected rates. Multiple skeletal abnormalities have been identified among fossil Homo specimens from the Pleistocene, including examples from the last 200,000 years, preserved by the practice of burial, as well as cases as old as 1.5 million years. Erik Trinkaus calculated the probability of discovering disorders from abnormal growth and development in the limited samples preserved from the Pleistocene, based on both modern human incidences of similar disorders and known size and shape distributions of Pleistocene samples. Around one-third of the abnormalities were classified as moderately common, with abnormalities expected in less than 1-5% of cases. Most of the rest of the abnormalities were rare to extremely rare, expected in less than 0.01-0.1% of cases, or had no known cause in recent humans. According to the author, the results stimulate further research on possible demographic factors, such as inbreeding, behind the unusually high incidence of skeletal abnormalities, the social structures in which such individuals lived, burial practices, and chronic stresses faced by Pleistocene foragers.

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Examples of developmental abnormalities in Pleistocene people. Left to right: the Tianyuan 1, Sunghir 3 and Dolní V?stonice 15 abnormal femora, Center, top to bottom: the Palomas 23 mandibular “flange”, the Rochereil 3 cranial lacuna, the long Sunghir 1 clavicle, the Malarnaud 1 incisor agenesis. Right, top to bottom: the Shanidar 1 sacral hiatus, the Pataud 1 polygenesis, and the Dolní V?stonice 16 cleft palate. Image courtesy of Erik Trinkaus.

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Article Source: PNAS news release

*”An abundance of developmental anomalies and abnormalities in Pleistocene people,” by Erik Trinkaus.

What the Teeth Show: Seasons of Neanderthal Birth and Weaning, First Evidence of Lead Exposure

By analyzing teeth of two 250,000-year-old French Neanderthals, scientists have shed light on the seasons when the Neanderthals were born, as well as on their weaning trajectories and their exposure to extreme climatic stress. The study also reveals the oldest documented exposure to lead in hominin remains. Together, these results show direct effects of climate on the growth and development of our ancestors in the distant past, important for understanding human evolution. Experts have long attempted to reveal the relationship between human evolution and climate change. Although environmental variability, such as extreme seasonal cold, is believed to have strongly influenced human evolution, it has proven very difficult to directly measure because of the coarseness of standard analytical methods. In a novel use of oxygen isotope and trace element analysis involving micro-sampling of tooth enamel from two Neanderthal individuals and one modern human from an archaeological site in southeastern France, Tanya M. Smith and colleagues investigated relationships between patterns of seasonal variation and Neanderthal life history. Oxygen isotopes in the approximately 250,000-year-old Neanderthals display multiyear patterns indicating winter and summer seasons, analysis of which suggests the Neanderthal individuals experienced cooler winters and otherwise more extreme seasonal periods compared to the more recent modern human from the same archeological site. This led to childhood development stresses during wintertime in the former, the authors say, based on further analyses. One of the Neanderthal samples shows elevated barium levels until nine months of age, consistent with nursing through that time, the authors say. It appears this individual was born in the spring and weaned in the fall around two and a half years of age, which is in line with the pattern in most mammals that give birth during times of increased food availability. Additionally, the researchers found evidence that both Neanderthals were exposed to lead at least twice in their early life. This represents the oldest documented exposure to lead in hominin remains, they say.

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Photograph of one of the Neanderthal children’s teeth. © Smith et al.

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A 250,000-year-old Neanderthal tooth yields an unprecedented record of the seasons of birth, nursing, illness, and lead exposures over the first three years of this child’s life. Tanya Smith & Daniel Green

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A 250,000 year-old Neanderthal tooth yields an unprecedented record of the seasons of birth, nursing, illness, and lead exposures over the first 3 years of this child’s life.
Smith et al. 2018 Science Advances

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Article Sources: AAAS Science Advances and CNRS news releases Science Advances is published by AAAS, the nonprofit science society.

The Indians of the Ecuadorian Amazon were using cocoa 5,300 years ago

CIRAD—Traces of cocoa dating back 5300 years have been found in ancient pots in the Ecuadorian Amazon. This is the oldest proof of cocoa use ever found. It predates the domestication of cocoa by the Olmec and the Maya in Central America by some 1500 years.

This evidence was collected in the southern Ecuadorian Amazon, at the Santa Ana La Florida (SALF) archaeological site near Palanda, discovered 16 years ago by the archaeologist Francisco Valdez and his Franco-Ecuadorian team (IRD/INPC) (2). The Mayo Chinchipe, the oldest known Amerindian civilization in the upper Amazon, had consumed cocoa almost continuously from at least 5300 years to 2100 years before present. Traces of houses and of a ceremonial site remain.

“Evidence of cocoa use was found by analyzing the starch grains characteristic of the genus Theobroma, traces of theobromine, a biochemical compound specific to mature cocoa beans, and ancient cocoa DNA found in ceramic vessels, some of which dated back more than 5300 years” , says Claire Lanaud, a geneticist from CIRAD specializing in cocoa, who is one of the lead authors of the study*. “The vessels came from tombs or domestic settings; they clearly showed that cocoa was used both as a funerary offering and for daily consumption.”

The ancient DNA analyses were conducted by a team of geneticists from CIRAD (1), in collaboration with the INPC, the IRD (2), and INRA (3), as part of a project on the past and present domestication of cocoa funded by Agropolis Fondation. After sequencing, the team demonstrated the presence of DNA fragments specific to the species Theobroma cacao, despite their severe degradation due to the humid tropical environment in which they were found.

The Santa Ana-La Florida archaeological site in Ecuador

The Santa Ana-La Florida archaeological site is located within the area of origin of the Nacional cocoa variety grown on the Pacific coast of Ecuador, from which all the fine cocoa produced in the country originated. The presence of seashells, such as spondylus and strombus, from the Pacific coast, at the archaeological site demonstrates that there were communication links between the peoples of the Pacific coast and those of the Amazon, such as the Mayo Chinchipe. “This latter group may therefore have played a major role in domesticating cocoa in general and the Nacional variety in particular.”

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Ceremonial site of Santa Ana La Florida archaeological site near Palanda, Ecuador. © C. Lanaud, CIRAD

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Article Source: CIRAD news release

*Zarrillo S. ±, Gaikwad N. ±, Lanaud C.±, Terry Powis T.,Viot C., Lesur I., Fouet O., Argout X., Guichoux E., Salin F., Loor Solorzano R.G., Bouchez O., Vignes H., Severts P., Hurtado J., Yepez A., Grivetti L., Blake M., Valdez F. The use and domestication of Theobroma cacao during the mid-Holocene in the upper Amazon. Nature Ecology and Evolution ± Lead authors of the study

Amazcacao: a new project on Amazon fine cocoas.

A new project launched in October 2018 to run for three years, funded by Montpellier University of Excellence (MUSE), will be continuing this work on the domestication of the fine and aromatic cocoas of the Amazon. The project, called Amazcacao, which is coordinated by CIRAD, is a multidisciplinary study covering aspects relating to the biodiversity of the cocoa trees in the Ecuadorian Amazon and its use, with the help of local people; the history and domestication of fine cocoa varieties, studied using paleogenomics; an understanding of the genetic and biochemical bases of cocoa aroma quality and sanitary quality; and the socioeconomic aspects of the crop.

*Study partners:

INPC: Instituto Nacional de Patrimonio Cultural, INIAP: Instituto Nacional de Investigación Agropecuaria, Ministry of Heritage and Culture (Ecuador);

University of Calgary, University of British Columbia (Canada);

University of California, UC-Davis, Kennesaw State University (USA);

CIRAD, HelixVenture, INRA, IRD (France).

Study reconstructs Neanderthal ribcage, offers new clues to ancient human anatomy

UNIVERSITY OF WASHINGTON—An international team of scientists has completed the first 3D virtual reconstruction of the ribcage of the most complete Neanderthal skeleton unearthed to date, potentially shedding new light on how this ancient human moved and breathed.

The team, which included researchers from universities in Spain, Israel, and the United States, including the University of Washington, focused on the thorax—the area of the body containing the rib cage and upper spine, which forms a cavity to house the heart and lungs. Using CT scans of fossils from an approximately 60,000-year-old male skeleton known as Kebara 2, researchers were able to create a 3D model of the chest—one that is different from the longstanding image of the barrel-chested, hunched-over “caveman.” The conclusions point to what may have been an upright individual with greater lung capacity and a straighter spine than today’s modern human.

The study is published Oct. 30 in Nature Communications.

“The shape of the thorax is key to understanding how Neanderthals moved in their environment because it informs us about their breathing and balance,” said Asier Gomez-Olivencia, an Ikerbasque Fellow at the University of the Basque Country and the study’s lead author.

And how Neanderthals moved would have had a direct impact on their ability to survive on the resources available to them, said Patricia Kramer, professor in the UW Department of Anthropology and corresponding author on the paper.

“Neanderthals are closely related to us with complex cultural adaptations much like those of modern humans, but their physical form is different from us in important ways,” she said. “Understanding their adaptations allows us to understand our own evolutionary path better.”

Neanderthals are a type of human that emerged about 400,000 years ago, living mostly from what is today Western Europe to Central Asia. They were hunter-gatherers who, in some areas, lived in caves and who weathered several glacial periods before going extinct about 40,000 years ago. Studies in recent years have suggested that Neanderthals and early Homo sapiens interbred, because evidence of Neanderthal DNA has turned up in many populations.

Over the past 150 years, Neanderthal remains have been found at many sites in Europe, Asia and the Middle East. This team worked with a skeleton labeled Kebara 2, also known as “Moshe,” which was found in Kebara Cave in Northern Israel’s Carmel mountain range in 1983. Though the cranium is missing, the remains of the young adult male are considered one of the most complete Neanderthal skeletons ever found. Two different forms of dating of the surrounding soil, thermoluminescence and electron spin resonance, put the age at somewhere between 59,000 and 64,000 years.

Discoveries and studies of other Neanderthal remains in the 19th and early 20th centuries gave rise to theories and images of a stereotypical, hunched-over caveman. Over time, further research clarified scientific understanding of many Neanderthal traits, but some debate has lingered over the structure of the thorax, the capacity of the lungs and what conditions Neanderthals might have been able to adapt to, or not.

Over the past decade, virtual reconstruction has become more commonplace in biological anthropology, Kramer explained. The approach is useful with fossils such as the thorax, where fragile bones make physical reconstruction difficult and risky.

Nearly two years ago, the same research team created a virtual reconstruction of the Kebara 2 spine, the first step in updating theories of Neanderthal biomechanics. The team’s paper, published in the book “Human Paleontology and Prehistory,” reaffirmed the likelihood of upright posture but pointed to a straighter spine than that of modern humans.

For this model of the thorax, researchers used both direct observations of the Kebara 2 skeleton, currently housed at Tel Aviv University, and medical CT scans of vertebrae, ribs and pelvic bones, along with 3D software designed for scientific use. “This was meticulous work,” said Alon Barash, a lecturer at Bar Ilan University in Israel. “We had to CT scan each vertebra and all of the ribs fragments individually and then reassemble them in 3D.”

They then used a technique called morphometric analysis to compare the images of Neanderthal bones with medical scans of bones from present-day adult men. “In the reconstruction process, it was necessary to virtually ‘cut’ and realign some of the parts that showed deformation, and mirror-image some of those that were not so well-preserved in order to get a complete thorax,” said Gomez-Olivencia.

The reconstruction of the thorax, coupled with the team’s earlier finding, shows ribs that connect to the spine in an inward direction, forcing the chest cavity outward and allowing the spine to tilt slightly back, with little of the lumbar curve that is part of the modern human skeletal structure. “The differences between a Neanderthal and modern human thorax are striking,” said Markus Bastir, senior research scientist at the Laboratory of Virtual Anthropology at the National Museum of Natural History in Spain.

“The Neanderthal spine is located more inside the thorax, which provides more stability,” said Gomez-Olivencia. “Also, the thorax is wider in its lower part.” This shape of the rib cage suggests a larger diaphragm and thus, greater lung capacity.

“The wide lower thorax of Neanderthals and the horizontal orientation of the ribs suggest that Neanderthals relied more on their diaphragm for breathing,” said senior author Ella Been of Ono Academic College. “Modern humans, on the other hand, rely both on the diaphragm and on the expansion of the rib cage for breathing. Here we see how new technologies in the study of fossil remains is providing new information to understand extinct species.”

What that means for how Kebara 2 lived is ripe for further research, Kramer said. How did Neanderthals breathe, and for what physical demands might they have needed powerful lungs? What does that tell us about how they moved, and the environment in which they lived? Did any of these physical traits make them more or less adaptive to climate change?

Reconstructing the thorax was an exercise in starting from scratch, deliberately trying to avoid being influenced by past theories of how Neanderthals looked or lived, Kramer said.

“Thinking through all the permutations of the different fragments, it was like a jigsaw without all the pieces. What do the pieces tell us?” she said. “People have told you it should be a certain way, but you want to make sure you’re not over-reconstructing, or reconstructing it the way you think it should be. You’re trying to maintain a neutral approach.”

Other authors of the study were Daniel Garcia-Martinez of the National Museum of Natural History and Mikel Arlegi, of the University of the Basque Country.

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Patricia Kramer, a University of Washington professor of anthropology, is part of an international team that completed a virtual 3D reconstruction of portions of a Neanderthal skeleton. Here, she shows part of the collection of model Neanderthal skulls. Dennis Wise, University of Washington

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This image from the virtual reconstruction shows how the ribs attach to the spine in an inward direction, forcing an even more upright posture than in modern humans. Gomez-Olivencia, et al

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If you liked this article, you may like The Last Neanderthals, a premium article in the Fall 2018 issue of Popular Archaeology.

Article Source: University of Washington news release

Interior northwest Indians used tobacco long before European contact

WASHINGTON STATE UNIVERSITY—PULLMAN, Wash. – Washington State University researchers have determined that Nez Perce Indians grew and smoked tobacco at least 1,200 years ago, long before the arrival of traders and settlers from the eastern United States. Their finding upends a long-held view that indigenous people in this area of the interior Pacific Northwest smoked only kinnikinnick or bearberry before traders brought tobacco starting around 1790.

Shannon Tushingham, a WSU assistant professor and director of its Museum of Anthropology, made the discovery after teaming up with David Gang, a professor in the Institute of Biological Chemistry, to analyze pipes and pipe fragments in the museum’s collection.

“Usually in archaeology we just find little pieces of artifacts, things that you might not think much of,” she said. “But the information that we can extract from them on a molecular level is phenomenal.”

Indeed, writing in the Proceedings of the National Academy of Sciences, the researchers say their dating of various materials reveals “the longest continuous biomolecular record of ancient tobacco smoking from a single region anywhere in the world.”

Tushingham first became interested in the subject when, while excavating plank houses in far northern California for her dissertation, she came across two soapstone pipes.

“I just thought, ‘Wouldn’t it be interesting to know what people were smoking?'” she said. “Then I started looking at the different plants and it wasn’t just tobacco. People smoked lots of different plants. I realized it was an open question whether people had smoked tobacco in many places in North America.”

Indigenous tobacco is scarce in the cool climate of the northwest. Coyote tobacco, or Nicotiana attenuata, is found mostly on sandy river bars, while the natural range of N. quadrivalvus lies south of southwestern Oregon.

Meanwhile, the more potent dried trade tobacco was easy to transport in bundles, or “twists,” and Hudson’s Bay Company explorers, fur traders and the Lewis and Clark expedition found an eager audience for it as they came through the region in the 1700 and 1800s.

“This occurred so rapidly and so early in the historic record that a complete understanding of in situ pre-contact smoking practices has been obscured,” Tushingham and Gang write in their paper.

In the 1930s, anthropologist Alfred Kroeber oversaw a survey of more than 200 tribes and bands west of the Rocky Mountains. In one of the ensuing monographs, “Salt, Dogs, Tobacco,” he reported that the smoking of non-tobacco products was “more universal,” with planting confined to a “long irregular area” from the Oregon coast into south-central California. An accompanying map, however, shows three spots in the Columbia River basin where tobacco could have been mixed with kinnikinnick.

Working with Nez Perce tribal leaders, Tushingham and Gang analyzed a dozen pipes and fragments from three sites on the Snake River. Gang said he could use a solvent to get the substance from a pipe and analyze it using mass spectrometry. That left the pipes intact.

The technique extracts molecular amounts of residue on the surface and inside of the pipes, Gang said. “We don’t want to destroy them. We don’t want to damage them. We had one pipe that was 5,000 years old that we were really worried about that was sandstone.”

Results were inconclusive, but the pipe was fine.

The researchers did detect nicotine in pipes from both after and well before Euro-American contact. None appeared to contain arbutin, a compound associated with kinnikinnick.

Because tobacco in the interior northwest needed to be planted, Tushingham said their finding offers a new view of native interactions with the landscape. Indigenous people have often been thought of as “passive consumers of the environment,” yet they managed camas and even grew clams on the coast, she said.

“I think it’s a very reasonable proposition that people were cultivating tobacco,” Tushingham said. “This is just another sign of the sophistication of cultures in this area and how they managed plants and animals.”

The researchers hope that their findings will inform native smoking-cessation programs, acknowledging the deep cultural role of tobacco while addressing health problems.

“If we know there’s this eons-long use of psychoactive plants, doesn’t that tell you something about human physiology, human health?” asked Tushingham. “Isn’t that important information to know in terms of what we would do for treating people today, if we know more about the evolutionary history of this powerful plant and its long history of use by people?”

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In this image from around 1861 Nez Perce Chief Lawyer holds an elbow pipe that was commonly used after trade tobacco spread across the Pacific Northwest. Washington State University researchers have found tobacco use among the Nez Perce goes way back, with nicotine in pipes 1,200 years old creating “the longest continuous biomolecular record of ancient tobacco smoking from a single region anywhere in the world.” University of Washington Libraries, Special Collections, NA 627

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Nicotiana quadravalvus is one of several species of tobacco that indigenous people used in religious and ceremonial practices. Washington State University researchers have found tobacco use among Nez Perce Indians goes way back, with nicotine in pipes 1,200 years old creating “the longest continuous biomolecular record of ancient tobacco smoking from a single region anywhere in the world.” Emily Hull

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Article Source: Washington Statue University news release

The research was funded by the National Science Foundation. The other co-authors on the paper are Korey Brownstein and William Damitio of WSU and Charles Snyder of the University of Tennessee Health Science Center.

Earliest hominin migrations into the Arabian Peninsula required no novel adaptations

MAX PLANCK INSTITUTE FOR THE SCIENCE OF HUMAN HISTORY—A new study, led by scientists from the Max Planck Institute for the Science of Human History and published in Nature Ecology and Evolution, suggests that early hominin dispersals beyond Africa did not involve adaptations to environmental extremes, such as to arid and harsh deserts. The discovery of stone tools and cut-marks on fossil animal remains at the site of Ti’s al Ghadah provides definitive evidence for hominins in Saudi Arabia at least 100,000 years earlier than previously known. Stable isotope analysis of the fossil fauna indicates a dominance of grassland vegetation, with aridity levels similar to those found in open savanna settings in eastern Africa today. The stable isotope data indicates that early dispersals of our archaic ancestors were part of a range expansion rather than a result of novel adaptations to new environmental contexts outside Africa.

Studies of early and late dispersals of hominin populations beyond Africa are important for understanding the course of global human evolution and what it means to be human. Although the species that make up the genus Homo are often termed ‘human’ in academic and public discourse, this evolutionary group (or genus), which emerged in Africa around 3 million years ago, is highly diverse. Indeed, there is continuing debate as to what extent our own species Homo sapiens, which emerged in Africa around 300,000 years ago, showed unique ecological plasticity in adapting to novel environments compared to other hominin members in the genus Homo.

Distinguishing ecological settings for members of the genus Homo outside Africa

It has recently been argued that early Homo sapiens occupied a diversity of extreme environments, including deserts, tropical rainforests, arctic, and high-altitude settings, around the world. By contrast, the dispersals of other earlier and contemporaneous species of Homo, such as Neanderthals, appear to be associated with generalized use of different forest and grassland mosaics in and among river and lake settings. A lack of palaeoenvironmental information has made it difficult to systematically test this idea and indeed a number of researchers maintain that non-Homo sapiens species demonstrate cultural and ecological adaptive flexibility.

‘Green Arabia’ and early human migrations

In spite of its crucial geographic position at the crossroads between Africa and Eurasia, the Arabian Peninsula has been astoundingly absent from discussions about early human expansions until recently. However, recent analysis of climate models, cave records, lake records, and animal fossils have shown that at certain points in the past, the harsh, hyper-arid deserts that cover much of Arabia today were replaced by ‘greener’ conditions that would have represented an attractive setting for various hominin populations.

Following the ‘savanna’? Direct environmental evidence for first steps ‘Out of Africa’

In the current paper, the researchers undertook renewed archaeological excavations and analysis of fossil fauna found at the site of Ti’s al Ghadah, in the Nefud Desert of northern Saudi Arabia. As one of the lead authors, Mathew Stewart says, “Ti’s al Ghadah is one of the most important palaeontological sites in the Arabian Peninsula and it currently represents the only dated collection of middle Pleistocene fossil animals in this part of the world, and includes animals such as elephant, jaguar and water birds.” Until now, however, the absence of stone tools has made linking these animals with early hominin presence uncertain.

Significantly, the research team found stone tools alongside evidence for the butchery of animals on bones, confirming a hominin presence in association with these animals 500,000 to 300,000 years ago. Michael Petraglia, the principal archaeologist of the project and a co-author on the paper says, “This makes Ti’s al Ghadah the first, early hominin-associated fossil assemblage from the Arabian Peninsula, demonstrating that our ancestors were exploiting a variety of animals as they wandered into the green interior.”

The authors were also able to innovatively apply geochemical methods to fossil animal tooth enamel to determine vegetation and aridity conditions associated with the movements of our ancestors into this region. The stable isotope findings highlight the presence of an abundance of grass in all animal diets, as well as aridity levels somewhat similar to those found in East Africa ‘savanna’ settings today. This information fits with analysis of the types of animals found on site, and indicates the availability of significant amounts of water at certain points in time.

Implications for our understanding of changing human adaptive capacities

“While these early hominin populations may have possessed significant cultural capacities, their movement into this part of the world would not have required adaptations to harsh and arid deserts,” Dr. Patrick Roberts, the lead author of the paper, explains. “Indeed, the isotope evidence suggests that this expansion is more characteristic of a range expansion similar to that seen among other mammals moving between Africa, the Levant, and Eurasia at this time.” More detailed study of past environments, closely associated with different forms of hominin species in the Arabian Peninsula and elsewhere should enable more refined testing as to whether our species is uniquely flexible in terms of its adaptations to varying environments.

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This is a sand dune in the Nefud Desert, Saudi Arabia. Palaeodeserts Project (Klint Janulis)

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Excavation of mammal fossils at the Ti’s al Ghadah site, Saudi Arabia. Palaeodeserts Project (Michael Petraglia)

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Mammal fossil recovered from the Ti’s al Ghadah site, Saudi Arabia. Palaeodeserts Project (Ian R. Cartwright)

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If you liked this article, see The First Arabians, a free premium article previously published in Popular Archaeology, and One Small Arabian Finger Bone, also a premium article previously published in Popular Archaeology.

Article Source: Max Planck Institute for the Science of Human History news release

The international consortium of researchers involved in this project is headed by the Max Planck Institute for the Science of Human History, in partnership with HRH Prince Sultan bin Salman and the Saudi Commission for Tourism and National Heritage. Additional partners include the Saudi Geological Survey, King Saud University and other key institutions in the United Kingdom and Australia.

New Projectile Point Style Could Suggest Two Separate Migrations into North America

Science Advances—Through excavation of a site in Texas, researchers have identified a particular style of projectile point – or triangular blade often attached to a weapon that would be thrown – dated between 13,500 and 15,500 years ago, they say. This is earlier than typical Clovis-style technologies dated to 13,000 years ago. The finding suggests that projectile points changed over time from the stemmed form found here into the more widespread, Clovis-style lanceolate fluted projectile point. It’s also possible, say the study’s authors, that the projectile point style they found in Texas is a distinct style created by people of an earlier, separate migration into the Americas. Clovis points – thought to date as early as 13,000 years ago – were once thought to reflect the earliest occupation of North America. However, more recent excavations in western North America have identified a different style of point technology – the Western Stemmed Tradition. The connections between the artifact assemblages of Clovis and Western Stemmed Traditions, however, remain unknown. Here, Michael R. Waters and his colleagues report more than 100,000 artifacts, including 328 tools and 12 complete and fragmented projectile points, excavated from the Buttermilk Creek Complex horizon of the Debra L. Friedkin site, which dates earlier than the Clovis history. From 19 optically stimulated luminescence dates of sediments, they determined the artifacts were between 13,500- and 15,500- years-old. The Buttermilk Creek Complex featured bladed projectile points that exhibited similarities to artifact assemblages of the Clovis, with lanceolate features. Waters and colleagues suggest that once developed, the lanceolate fluted point technology (associated with Clovis) could have spread over much of North America into northern Mexico, or alternatively, the stemmed and lanceolate point traditions may be evidence of two separate human migrations into North America.

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Excavations at the Debra L. Friedkin site 2016. Center for the Study of the First Americans, Texas A&M University

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A 15,000-year-old stemmed point tradition. Center for the Study of the First Americans, Texas A&M University

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A stemmed lanceolate projectile point that is about 15,000 years old. Center for the Study of the First Americans, Texas A&M University

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Read a more in-depth article about the findings at the Debra L. Friedkin site, The First Americans, published previously as a premium article (now free) in Popular Archaeology. 

Source: A Science Advances news release. Science Advances is published by AAAS, the nonprofit science society.

Ancient Andean genomes show distinct adaptations to farming and altitude

AMERICAN SOCIETY OF HUMAN GENETICS, SAN DIEGO, Calif. – Ancient populations in the Andes of Peru adapted to their high-altitude environment and the introduction of agriculture in ways distinct from other global populations that faced similar circumstances, according to findings* presented at the American Society of Human Genetics (ASHG) 2018 Annual Meeting in San Diego, Calif.

John Lindo, PhD, JD, assistant professor of anthropology at Emory University, and a group of international collaborators headed by Anna Di Rienzo, PhD, at the University of Chicago and Mark Aldenderfer, PhD, at the University of California, Merced, set out to use newly available samples of 7,000-year-old DNA from seven whole genomes to study how ancient people in the Andes adapted to their environment. They compared these genomes with 64 modern-day genomes from both highland Andean populations and lowland populations in Chile, in order to identify the genetic adaptations that took place before the arrival of Europeans in the 1500s.

“Contact with Europeans had a devastating impact on South American populations, such as the introduction of disease, war, and social disruption,” explained Dr. Lindo. “By focusing on the period before that, we were able to distinguish environmental adaptations from adaptations that stemmed from historical events.”

They found that Andean populations’ genomes adapted to the introduction of agriculture and resulting increase in starch consumption differently from other populations. For example, the genomes of European farming populations show an increased number of copies of the gene coding for amylase, an enzyme in saliva that helps break down starch. While Andeans also followed a high-starch diet after they started to farm, their genomes did not have additional copies of the amylase gene, prompting questions about how they may have adapted to this change.

Similarly, Tibetan genomes, which have been studied extensively for their adaptations to high altitude, show many genetic changes related to the hypoxia response – how the body responds to low levels of oxygen. The Andean genomes did not show such changes, suggesting that this group adapted to high altitude in another way.

The researchers also found that after contact with Europeans, highland Andeans experienced an effective population reduction of 27 percent, far below the estimated 96 percent experienced by lowland populations. Previous archaeological findings showed some uncertainty to this point, and the genetic results suggested that by living in a harsher environment, highland populations may have been somewhat buffered from the reach and resulting effects of European contact. The findings also showed some selection for immune-related genes after the arrival of Europeans, suggesting that Andeans who survived were better able to respond to newly introduced diseases like smallpox.

Building on these findings, Dr. Lindo and his colleagues are currently exploring a new set of ancient DNA samples from the Incan capital Cusco, as well as a nearby lowland group. They are also interested in gene flow and genetic exchange resulting from the wide-ranging trade routes of ancient Andeans.

“Our findings thus far are a great start to an interesting body of research,” said Dr. Lindo. “We would like to see future studies involving larger numbers of genomes in order to achieve a better resolution of genetic adaptations throughout history,” he said.

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The ancient Inka site of Macchu Picchu, nestled in the Andes. Martin St-Amant, Wikimedia Commons

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Article Source: American Society of Human Genetics news release

*Lindo J et al. (2018 Oct 17). Abstract: The genetic prehistory of the Andean highlands 7,000 years BP through European contact. Presented at the American Society of Human Genetics 2018 Annual Meeting. San Diego, California.

What Contributed to the Downfall of the Ancient City of Angkor in Modern Cambodia?

Monsoon-driven flooding weakened the water infrastructural network of Angkor, likely leading to the fall of this urban infrastructural network – the largest of the preindustrial world – according to a new analysis*. The findings may help experts better understand the vulnerabilities of modern infrastructural networks in urban environments where high-impact, low-frequency weather events pose a threat, say the study’s authors. The multifaceted infrastructural networks seen in cities provide critical services to many people around the world. According to Dan Penny and colleagues, the study of the stability of preindustrial urban networks stressed by climatic variation can provide important insights into the stability of such networks over long periods of time. Here, Penny et al. analyzed the topology of the ancient city of Angkor, one of the world’s most extensive cities by the 13th century CE. It featured canals, moats and reservoirs used to acquire, store and distribute water resources, as well as to regulate flooding. The authors investigated the ancient city’s topological vulnerability to erosion and sedimentation as caused by variations in rainfall conditions. After modeling the city’s infrastructure network based on archeological remote sensing and mapping, the researchers applied a numerical simulation model of erosion and sedimentation within the water network to determine whether the processes could change how water traveled through the network. They found that very large floods would result in systematic instability of the water distribution network, with the damage more severe near important upstream junctions. Extreme rainfall occurred in mainland Southeast Asia during the final decades of the 14th century and likely forced the network into a sudden unstable phase that contributed to the fragmentation of Angkor’s infrastructure network at that time, Penny et al. say.

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Sunrise at Angkor Wat. Magnetic Manifestations, Wikimedia Commons

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If you liked this article, you will like Undiscovered Country, a free premium article published previously in Popular Archaeology.

Article Source: A Science Advances news release. Science Advances is a publication of the AAAS (American Association for the Advancement of Science)

*“The demise of Angkor: Systemic vulnerability of urban infrastructure to climatic variations,” by D. Penny; C. Zachreson; R. Fletcher; D. Lau; J. Lizier; N. Fischer; M. Prokopenko at University of Sydney in Sydney, NSW, Australia; D. Evans; C. Pottier at École Française d’Extrême-Orient in Paris, France.

Extensive trade in fish between Egypt and Canaan already 3,500 years ago

JOHANNES GUTENBERG UNIVERSITAET MAINZ—Some 3,500 years ago, there was already a brisk trade in fish on the shores of the southeastern Mediterranean Sea. This conclusion follows from the analysis of 100 fish teeth that were found at various archeological sites in what is now Israel. The saltwater fish from which these teeth originated is the gilthead sea bream, which is also known as the dorade. It was caught in the Bardawil lagoon on the northern Sinai coast and then transported from Egypt to sites in the southern Levant. This fish transport persisted for about 2,000 years, beginning in the Late Bronze Age and continuing into the early Byzantine Period, roughly 300 to 600 AD. “Our examination of the teeth revealed that the sea bream must have come from a very saline waterbody, containing much more salt than the water in the Mediterranean Sea,” said Professor Thomas Tütken of Johannes Gutenberg University Mainz (JGU). The geoscientist participated in the study together with colleagues from Israel and Göttingen. The Bardawil lagoon formed 4,000 years ago, when the sea level finally stabilized after the end of the last Ice Age. The lagoon was fished intensively and was the point of origin of an extensive fish trade.

As demonstrated by archeological finds, fishing was an important economic factor for many ancient cultures. In the southern Levant, the gilthead sea bream with the scientific name of Sparus aurata was already being fished by local costal fishermen 50,000 years ago. More exotic fish, such as the Nile perch, were already being traded between Egypt and Canaan over 5,000 years ago. However, the current study shows the extent to which the trade between the neighbors increased in the Late Bronze Age and continued for 2,000 years into the Byzantine Period. “The Bardawil lagoon was apparently a major source of fish and the starting point for the fish deliveries to Canaan, today’s Israel, even though the sea bream could have been caught there locally,” stated co-author Professor Andreas Pack from the University of Göttingen.

Fish teeth document over 2,000 years of trade

Gilthead sea bream are a food fish that primarily feed on crabs and mussels. They have a durophagous dentition with button-shaped teeth that enable them to crush the shells to get at the flesh. For the purposes of the study, 100 large shell-cracking teeth of gilthead sea bream were examined. The teeth originate from 12 archeological sites in the southern Levant, some of which lie inland, some on the coast, and cover a time period from the Neolithic to the Byzantine Period. One approach of the researchers was to analyze the content of the oxygen isotopes ^18O and ^16O in the tooth enamel of the sea bream. The ratio of ^18O to ^16O provides information on the evaporation rate and thus on the salt content of the surrounding water in which the fish lived. In addition, the researchers were able to estimate the body size of the fish on the basis of the size of the shell-cracking teeth.

The analyses showed that some of the gilthead sea bream originated from the southeastern Mediterranean but that roughly three out of every four must have lived in a very saline body of water. The only water that comes into question in the locality is that of the Bardawil lagoon, the hypersaline water of which has a salt content of 3.9 to 7.4 percent, providing the perfect environment for the growth of sea bream. The Bardawil lagoon on the Sinai coast is approximately 30 kilometers long, 14 kilometers wide, and has a maximum depth of 3 meters. It is separated from the Mediterranean by a narrow sand bar.

“There was a mainland route from there to Canaan, but the fish were probably first dried and then transported by sea,” added Tütken. Even back then, sea bream were probably a very popular food fish, although it is impossible to estimate actual quantities consumed. However, it became apparent that the fish traded from the period of the Late Bronze Age were significantly smaller than in the previous era.

According to the researchers, this reduction in body size is a sign of an increase in the intensity of fishing that led to a depletion of stocks, which is to be witnessed also in modern times. “It would seem that fishing and the trade of fish expanded significantly, in fact to such a degree that the fish did not have the chance to grow as large,” continued Tütken, pointing out that this was an early form of the systematic commercial exploitation of fish, a type of proto-aquaculture, which persisted for some 2,000 years.

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Jaw with a durophagous dentition consisting of teeth with thick enamel of the gilthead sea bream (Sparus aurata): The large molariform tooth was used for oxygen isotope analysis and to estimate the size of the fish. photo/©: Guy Sisma-Ventura, Israel

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Changes of the oxygen isotopes in the crushing teeth as well as the fish body mass over the last 10,000 years: From the Late Bronze Age, the sea bream originated from the hypersaline Bardawil lagoon but their body mass was smaller than before, which is an indication of intensification of fishing. ill./©: Thomas Tütken, JGU

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Map of the archeological sites in Israel where the sea bream teeth analyzed were found. Also shown is the Bardawil lagoon on the north coast of the Sinai Peninsula, from which the sea bream remains found in Israel dating back as far as the Late Bronze Age primarily originated. ill./©: Thomas Tütken, JGU

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Article Source: JOHANNES GUTENBERG UNIVERSITAET MAINZ news release

Geoscientist Professor Thomas Tütken of the Department of Applied and Analytical Paleontology at JGU received an ERC Consolidator Grant from the European Research Council in 2016. The current research study was undertaken jointly with another ERC project of his colleagues in Israel. Dr. Guy Sisma-Ventura, who currently works at the Israel Oceanographic and Limnological Research (IOLR), stayed for a month in Mainz, where the researchers performed the major part of the oxygen isotope analyses.

‘Vampire burial’ reveals efforts to prevent child’s return from grave

UNIVERSITY OF ARIZONA—The discovery of a 10-year-old’s body at an ancient Roman site in Italy suggests measures were taken to prevent the child, possibly infected with malaria, from rising from the dead and spreading disease to the living.

The skeletal remains, uncovered by archaeologists from the University of Arizona and Stanford University, along with archaeologists from Italy, included a skull with a rock intentionally inserted into the mouth. Researchers believe the stone may have been placed there as part of a funeral ritual designed to contain disease – and the body itself.

The discovery of this unusual, so-called “vampire burial” was made over the summer in the commune of Lugnano in Teverina in the Italian region of Umbria, where UA archaeologist David Soren has overseen archaeological excavations since 1987.

“I’ve never seen anything like it. It’s extremely eerie and weird,” said Soren, a Regents’ Professor in the UA School of Anthropology and Department of Religious Studies and Classics. “Locally, they’re calling it the ‘Vampire of Lugnano.'”

A 10-year-old was discovered lying on its side in a fifth-century Italian cemetery previously believed to be designated for babies, toddlers and unborn fetuses. David Pickel/Stanford University

The discovery was made at La Necropoli dei Bambini, or the Cemetery of the Babies, which dates to the mid-fifth century when a deadly malaria outbreak swept the area, killing many vulnerable babies and small children. The bodies of the young victims were buried at the site of an abandoned Roman villa that was originally constructed at the end of the first century B.C.

Until now, archaeologists believed the cemetery was designated specifically for infants, toddlers and unborn fetuses; in previous excavations of more than 50 burials, a 3-year-old girl was the oldest child found.

The discovery of the 10-year-old, whose age was determined based on dental development but whose sex is unknown, suggests that the cemetery may have been used for older children as well, said bioarcheologist Jordan Wilson, a UA doctoral student in anthropology who analyzed the skeletal remains in Italy.

“There are still sections of the cemetery that we haven’t excavated yet, so we don’t know if we’ll find other older kids,” Wilson said.

Excavation director David Pickel, who has a master’s degree in classical archaeology from the UA and is now a doctoral student at Stanford, said the discovery has the potential to tell researchers much more about the devastating malaria epidemic that hit Umbria nearly 1,500 years ago, as well as the community’s response to it.

“Given the age of this child and its unique deposition, with the stone placed within his or her mouth, it represents, at the moment, an anomaly within an already abnormal cemetery,” Pickel said. “This just further highlights how unique the infant – or now, rather, child – cemetery at Lugnano is.”

Witchcraft as disease control

In previous excavations at the Cemetery of the Babies, archaeologists found infant and toddler bones alongside items like raven talons, toad bones, bronze cauldrons filled with ash and the remains of puppies that appear to have been sacrificed – all objects commonly associated with witchcraft and magic. In addition, the body of the 3-year-old girl had stones weighing down her hands and feet – a practice used by different cultures throughout history to keep the deceased in their graves.

“We know that the Romans were very much concerned with this and would even go to the extent of employing witchcraft to keep the evil – whatever is contaminating the body – from coming out,” Soren said.

The “evil,” in the case of the babies and toddlers uncovered in Lugnano, was malaria, Soren believed. DNA testing of several of the excavated bones supported his theory.

Although the 10-year-old’s remains have not yet undergone DNA testing, the child had an abscessed tooth – a side effect of malaria – that suggests he or she may also have fallen victim to the disease, Wilson said.

The child was one of five new burials uncovered at the cemetery over the summer. The body was found lying on its left side in a makeshift tomb created by two large roof tiles propped against a wall – an alla cappuccina-style burial typical of Roman Italy.

“Knowing that two large roof tiles were used for this burial, I was expecting something unique to be found inside, perhaps a ‘double-inhumation’ – not uncommon for this cemetery – where a single burial contains two individuals,” Pickel said. “After removing the roof tiles, however, it became immediately clear to us that we were dealing with an older individual.”

The open position of the child’s jaw, which would not have opened naturally during decomposition with the body positioned on its side, suggests that the rock was intentionally inserted in the mouth after death, Wilson said. Teeth marks on the surface of the stone provide further evidence that it was placed purposefully.

The 10-year old was the first at the cemetery to be found with a stone in its mouth. Similar burials have been documented in other locations, including in Venice, where an elderly 16th-century woman dubbed the “Vampire of Venice” was found with a brick in her mouth in 2009. In Northamptonshire, England, in 2017, an adult male from the third or fourth century was found buried facedown with his tongue removed and replaced with a stone.

These types of burials are often referred to as vampire burials, since they are associated with a belief that the dead could rise again. Other examples of vampire burials throughout history include bodies being staked to the ground through the heart or dismembered prior to interment.

“This is a very unusual mortuary treatment that you see in various forms in different cultures, especially in the Roman world, that could indicate there was a fear that this person might come back from the dead and try to spread disease to the living,” Wilson said.

Archaeologists will return to Lugnano next summer to complete excavations of the cemetery and learn more about a dark time in history.

“It’s a very human thing to have complicated feelings about the dead and wonder if that’s really the end,” Wilson said. “Anytime you can look at burials, they’re significant because they provide a window into ancient minds. We have a saying in bioarchaeology: ‘The dead don’t bury themselves.’ We can tell a lot about people’s beliefs and hopes and by the way they treat the dead.”

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A rock was inserted into the mouth of a 10-year-old to keep the deceased child from rising from the grave and spreading malaria, researchers believe. David Pickel/Stanford University

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This is the rock that was inserted into the child’s mouth in this so-called “vampire burial.” David Pickel/Stanford University

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For a more in-depth article about “vampire burial” practices discovered through archaeology, see the previously published free premium article, Walking Dead and Vengeful Spirits, published in Popular Archaeology.

Article Source: University of Arizona news release

Reconstructing the history of mankind with the help of fecal sterols — first test on the Maori

UNIVERSITÀ CA’ FOSCARI VENEZIA—It is now possible to tell the story of mankind’s presence and evolution on the planet by analyzing trends in soil and sediment accumulation of fecal sterols, chemical compounds which are crucial in human physiology. Scientists at Ca’ Foscari University of Venice and the Institute for the Dynamics of Environmental Processes of the National Research Council (CNR-IDPA) have identified and dated traces of sterols within the sediments of two New Zealand lakes, thus proving the presence of the Maori people who, starting from around 1280, colonized the two oceanic islands and cleared them of forests in just a few decades to make space for fields and pastures. The study has just been published in the scientific journal Scientific Reports.

The analyses were carried out in the laboratories of Venice on cores of sediment taken from Lakes Diamond and Kirkpatrick, located on New Zealand’s South Island. By analyzing the microparticles of coal and pollen, researchers had already found evidence of significant forest fires as well as of sudden changes to the New Zealand landscape during the fourteenth century, when the deforested areas made space available for grass and shrubs to grow quickly and in a manner that was without precedent. Archaeological and paleoecological evidence quite conclusively attribute the deforestation to the Maori people, but this new study provides definitive scientific proof of their arrival in the area and of the enormous impact that a group of so few individuals had on the native forest in a very short time, to the extent that it was irreversibly jeopardized. In addition, the research demonstrates the validity of the method tested by the Italian researchers for reconstructing the history of humankind’s presence in a given region.

“Lakes collect traces of the feces of populations that have lived in surrounding areas, and these are deposited on the lake floors,” explains Elena Argiriadis, postdoc at the Department of Environmental Sciences, Informatics and Statistics at Ca’ Foscari, one of the authors of the study, “offering a continuous recording of the centuries of human presence. The concentration of coprostanol, the sterol most abundant in human feces, graphs a trend which over time nearly matches that of fire-related biomarkers, with a peak between 1345 and 1365 approximately, and is consistent with the profound environmental transformation which took place in New Zealand following the arrival of the Maori.”

“This research is part of a series of studies on mankind’s impact, through our history and prehistory, on environment and climate, analyzing biomarkers archived within ice or sediment extracts from all over the planet (the Early Human Impact project, funded by the European Research Council),” explains Carlo Barbante, professor of Analytical Chemistry at Ca’ Foscari and director of the CNR-IDPA. “Traces of human excrement also tell of the Europeans’ arrival on the southern island of New Zealand, starting in the 1800s. The exponential growth in the concentration of fecal sterols vividly demonstrates the rapid increase in the population of the area, which has been ongoing since the beginning of the nineteenth century. The method can now be applied to nearby lake sediments and soils, in which the history of human settlement is not so well-documented as in the case of New Zealand, helping to map the movements of populations over time”.

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Aerial view of Diamond Lake in New Zealand.

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The study was conducted in collaboration with scientists from Montana State University, the U.S. Geological Survey, the Geosciences and Environmental Change Science Center, the Landcare Research center of New Zealand and the University of Auckland.

Article Source: A UNIVERSITÀ CA’ FOSCARI VENEZIA news release

Ancient Khmer City of Koh Ker was occupied for centuries longer than previously thought

PLOS—The classic account of the ancient city of Koh Ker is one of a briefly-occupied and abruptly-abandoned region, but in reality, the area may have been occupied for several centuries beyond what is traditionally acknowledged, according to a study published October 10, 2018 in the open-access journal PLOS ONE by Tegan Hall of the University of Sydney, Australia and colleagues.

Koh Ker was part of the Khmer kingdom during the Angkor period in what is now Cambodia. For a mere two decades in the tenth century CE, the city served as royal capital, and it has long been proposed that after the royal seat moved back to Angkor, the city and its surroundings were abandoned. In this study, Hall and colleagues tested this theory by analyzing charcoal and pollen remains in sediment cores spanning several centuries in three Koh Ker localities, including the moat of the main central temple. From these data, they inferred a long history of fluctuations in fire regimes and vegetation which are highly indicative of patterns of human occupation and land use over time.

The newly-painted picture is of a region that was occupied well before the Angkor period, at least as far back as the late 7th century CE, and continuing seven centuries or more after the royal seat’s departure. The authors suggest that the mobility of royal houses may have had less of an impact on regional populations in the Khmer kingdom than previously thought. This study also highlights the utility of palaeoecological tools to reconstruct the occupational history of ancient urban settlements.

Hall adds: “When the environmental record is analyzed, it becomes clear that Koh Ker was much more than a temporary 10th century capital of the Khmer kingdom. The settlement history of the site is extensive and complex, beginning in the pre-Angkor period and lasting for centuries beyond the decline of Angkor.”

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These are coring locations across Koh Ker and its surrounds. Background image supplied by Google Earth. Hall et al., 2018

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If you liked this article, you may like Living in the Shadow of Angkor, a previously published premium article in Popular Archaeology.

Article Source: PLOS ONE news release

*Hall T, Penny D, Hamilton R (2018) Re-evaluating the occupation history of Koh Ker, Cambodia, during the Angkor period: A palaeo-ecological approach. PLoS ONE 13(10): e0203962.