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New technique provides accurate dating of ancient skeletons

EUROPEAN SOCIETY OF HUMAN GENETICS—Milan, Italy: Interest in the origins of human populations and their migration routes has increased greatly in recent years. A critical aspect of tracing migration events is dating them. However, the radiocarbon techniques*, that are commonly used to date and analyze DNA from ancient skeletons can be inaccurate and not always possible to apply. Inspired by the Geographic Population Structure model that can track mutations in DNA that are associated with geography, researchers have developed a new analytic method, the Time Population Structure (TPS), that uses mutations to predict time in order to date the ancient DNA.

Dr Umberto Esposito, a postdoctoral researcher in the laboratory of Dr Eran Elhaik, Department of Animal and Plant Sciences at the University of Sheffield, Sheffield, UK, will tell the annual conference of the European Society of Human Genetics today (Monday) that TPS can calculate the mixtures of DNA deriving from different time periods to estimate its definitive age. “This introduces a completely new approach to dating. At this point, in its embryonic state, TPS has already shown that its results are very similar to those obtained with traditional radiocarbon dating. We found that the average difference between our age predictions on samples that existed up to 45,000 years ago, and those given by radiocarbon dating, was 800 years. This study adds a powerful instrument to the growing toolkit of paleogeneticists that can contribute to our understanding of ancient cultures, most of which are currently known from archaeology and ancient literature,” says Dr Esposito.

Radiocarbon technology requires certain levels of radiocarbon on the skeleton, and this is not always available. In addition, it is a delicate procedure that can yield very different dates if done incorrectly. The new technique provides results similar to those obtained by radiocarbon dating, but using a completely new DNA-based approach that can complement radiocarbon dating or be used when radiocarbon dating is unreliable.

“This permits us to open a powerful window on our past. The study of genetic data allows us to uncover long-lasting questions about migrations and population mixing in the past. In this context, dating ancient skeletons is of key importance for obtaining reliable and accurate results,” says Dr Esposito. “Through this work, together with other projects that we are working on in the lab, we will be able to achieve a better understanding of the historical developments that took place from the beginning of the Neolithic period, with the introduction of farming practices in Europe, and throughout the Bronze and Iron Ages. These periods include some of the most crucial events involving the population movements and replacements that shaped our world.”

The technique is also expected to be valuable for genealogy. “When applying our ancient DNA dating technology to modern genomes, we have seen that some populations have more ancient genomes than others, and this can be helpful in establishing individual origins,” says Dr Esposito.

Health research will benefit too. Since the study of genetic disorders is closely tied up with questions of ancestry and population stratification, being able to analyze the homogeneity of populations is of vital importance to epidemiologists.

The researchers are currently compiling a larger dataset to increase the geographical/time coverage of their model and improve its accuracy. “Given the rapid increase in the number of ancient skeletons with published DNA, we believe that our technique will be useful to develop alternative hypotheses,” Dr Esposito will say.

Chair of the ESHG conference, Professor Joris Veltman, Director of the Institute of Genetic Medicine at Newcastle University in Newcastle, United Kingdom, said: “This study shows how DNA derived from ancient skeletons can be used to more accurately determine the age of the skeleton than traditional radiocarbon tracing methods. This is another example of the power of modern genomics technologies to assist in helping us understand where we come from, how the journeys of our forefathers have helped shape our current genome and how this now impacts our current abilities and weaknesses, including risks of disease.”

Article Source: European Society of Human Genetics news release

*Radiocarbon dating is a method for determining the age of an object by analysing the amount of radioactive carbon dioxide it contains. When an animal or plant dies, it stops exchanging carbon with its environment, and measuring the amount that remains provides a method of determining when it died.

Cover image, above right: A Neolithic period skeleton unearthed in Israel. Photograph by Yosef Galili, Ehud Galili, Itamar Greenberg, Wikimedia Commons

Ancient agricultural activity caused lasting environmental changes

UNIVERSITY OF BRITISH COLUMBIA—Agricultural activity by humans more than 2,000 years ago had a more significant and lasting impact on the environment than previously thought. The finding—discovered by a team of international researchers led by the University of British Columbia—is reported in a new study* published today in the journal Science Advances.

The researchers found that an increase in deforestation and agricultural activity during the Bronze Age in Ireland reached a tipping point that affected Earth’s nitrogen cycle—the process that keeps nitrogen, a critical element necessary for life, circulating between the atmosphere, land and oceans.

“Scientists are increasingly recognizing that humans have always impacted their ecosystems, but finding early evidence of significant and lasting changes is rare,” said Eric Guiry, the study’s lead author and a postdoctoral research fellow in UBC’s department of anthropology. “By looking at when and how ancient societies began to change soil nutrients at a molecular level, we now have a deeper understanding of the turning point at which humans first began to cause environmental change.”

For the study, the researchers performed stable isotope analyses on 712 animal bones collected from at least 90 archaeological sites in Ireland. The researchers found significant changes in the nitrogen composition of soil nutrients and plants that made up the animals’ diet during the Bronze Age.

The researchers believe the changes were the result of an increase in the scale and intensity of deforestation, agriculture and pastoral farming.

While these results are specific to Ireland during the Bronze Age, Guiry said the findings have global implications.

“The effect of human activities on soil nitrogen composition may be traceable wherever humans have extensively modified landscapes for agriculture,” he explained. “Our findings have significant potential to serve as a model for future research.”

Article Source: University of British Columbia news release

*The study, “Anthropogenic changes to the Holocene nitrogen cycle in Ireland,” was co-authored by researchers at the Institute of Technology Sligo, Trent University, the University of Oxford, Queen’s University Belfast, and Simon Fraser University.


New research unveils true origin of ancient turquoise

DICKINSON COLLEGE—(Carlisle, Pa., June 13, 2018) – New research published today in the journal Science Advances overturns more than a century of thought about the source of turquoise used by ancient civilizations in Mesoamerica, the vast region that extends from Central Mexico to Central America. For more than 150 years, scholars have argued that the Aztec and Mixtec civilizations, which revered the precious, blue-green mineral, acquired it through import from the American Southwest. However, extensive geochemical analyses reveal that the true geologic source of Aztec and Mixtec turquoise lies within Mesoamerica.

Geochemist Alyson Thibodeau, assistant professor of earth sciences at Dickinson College, and a team of researchers from the University of Arizona, California State University at San Bernardino, and the Museo del Templo Mayor in Mexico City, measured the isotopic signatures of Mesoamerican turquoise artifacts associated with both the Aztecs and Mixtecs. These isotopic signatures function like fingerprints that can be used to determine the geologic origins of the turquoise.

Specifically, Thibodeau and her research team carried out analyses of lead and strontium isotopes on fragments of turquoise-encrusted mosaics, which are one of the most iconic forms of ancient Mesoamerican art. Their samples include dozens of turquoise mosaic tiles excavated from offerings within the Templo Mayor, the ceremonial and ritual center of the Aztec empire, and which is located in present-day Mexico City. They also analyzed five tiles associated with Mixteca-style objects held by the Smithsonian’s National Museum of the American Indian. The analyses revealed that turquoise artifacts had isotopic signatures consistent with geology of Mesoamerica, not the Southwestern United States.

“This work revises our understanding of these relatively rare objects and provides a new perspective on the availability of turquoise, which was a highly valued luxury resource in ancient Mesoamerica,” said Thibodeau. The work is the result of a decade-long collaboration between archaeologists and isotope geochemists to understand the nature of turquoise circulation and trade across southwestern North America. In earlier published research, Thibodeau showed that isotopic signatures could distinguish among turquoise deposits across the southwestern U.S. and identified the geologic sources of turquoise artifacts from archaeological sites in Arizona and New Mexico.

Thibodeau said that long-standing assumption that Mesoamerican civilizations imported turquoise from the Southwest had not been fully substantiated with evidence and that the new geochemical measurements unveil a different story. “These findings potentially re-shape our understanding of both the nature and extent of long-distance contacts between Mesoamerican and Southwestern societies, said Thibodeau. “I hope this inspires people to be skeptical of claims.”


Close up view of Mixteca-style mask decorated with turquoise mosaic from the collections of the Smithsonian Institution-National Museum of the American Indian. NMAI Catalog #10/8712. Alyson M. Thibodeau


Close up view of Mixteca-style shield decorated with turquoise mosaic from the collections of the Smithsonian Institution-National Museum of the American Indian. NMAI Catalog #10/8708. Frances F. Berdan


Reconstructed turquoise mosaic disk from Offering 99 in the Templo Mayor. Oliver Santana. Reproduced with permission from Editorial Raices.


Article Source: Dickinson College news release



Research provides insights on World War II naval battle site

WILEY—The remains of World War II naval battle sites can be found under water, but most have not yet been subject to archaeological investigation. A new International Journal of Nautical Archaeology study* provides precise geographic information for the preservation, long-term research, and future use of a historically important World War II battle site on the seafloor off the coast of Okinawa, Japan.

The study focuses on the USS Emmons, a 106m US Navy Gleaves-class destroyer minesweeper that sank in 40m of water off Okinawa Island after kamikaze attack in 1945. A record of the site was made using an innovative method incorporating precise control points obtained from high-resolution multibeam echosounding bathymetry to generate 3D models using structure-from-motion photogrammetry. The 3D models produced can be used for sharing information about this underwater cultural heritage and for future monitoring of the archaeological remains.

“This article is not only presenting an innovative methodology for precise 3D mapping of the seafloor. We hope it also serves as a bridge to peace for both Japan and the U.S. and provides materials for future education,” said lead author Prof. Hironobu Kan, of Kyushu University, in Japan.


USS Emmons (DD-457) at anchor, circa 1942. The ship is painted in Camouflage Measure 12 (Modified) U.S. Naval History and Heritage Command Photograph.


Article Source: Wiley news release

*”Assessment and Significance of a World War II battle site: recording the USS Emmons using a High?Resolution DEM combining Multibeam Bathymetry and SfM Photogrammetry.” Hironobu Kan, Chiaki Katagiri, Yumiko Nakanishi, Shin Yoshizaki, Masayuki Nagao and Rintaro Ono. The International Journal of Nautical Archaeology; Published Online: June 12, 2018. (DOI: 10.1111/1095-9270.12301).


Ancient DNA and adoption of agriculture in North Africa

Researchers report* evidence of migrations from Europe to North Africa during the Neolithic period. The adoption of agriculture during the Neolithic represents a major development in human history. The process of agricultural adoption, known as the Neolithic transition, in North Africa remains largely uncharacterized, and it is unclear whether this process was driven by local populations adopting cultural and technological innovations or by the migration of people. Rosa Fregel and colleagues tested the possibilities by performing genome-wide analyses of human remains from Neolithic archaeological sites in Morocco. Individuals from the Early Neolithic site of Ifri n’Amr or Moussa, dated to approximately 5000 BCE, had similar ancestry to Later Stone Age individuals from North Africa. This ancestral signature is largely restricted to North Africa in present-day populations. By contrast, Late Neolithic individuals from the Kelif el Boroud site, dated to approximately 3000 BCE, shared only around half of their ancestry with Early Neolithic and Later Stone Age North Africans. The remaining half of their ancestry was shared with Early Neolithic individuals from southern Spain, suggesting that migration across the Strait of Gibraltar occurred between the Early and Late Neolithic. The results suggest that the early stages of the Neolithic transition in North Africa involved the adoption of technological innovations from neighboring areas by the local population, while subsequent migrations from Europe influenced further Neolithic developments, according to the authors.

Article Source: PNAS news release

*“Ancient genomes from North Africa evidence prehistoric migrations to the Maghreb from both the Levant and Europe,” by Rosa Fregel et al.


Late Pleistocene human mandibles from the Niah Caves may hint at ancient diets

PLOS—Three human mandibles may provide new insight into the diet of Late Pleistocene hunter-gatherers in Borneo, according to a study* published June 6, 2018 in the open-access journal PLOS ONE by Darren Curnoe from the University of New South Wales, Australia, and colleagues.

Little is known about the early hunter-gatherer populations that lived in island Southeast Asia since human remains from the Late Pleistocene-early Holocene era are extremely rare. The Niah Caves in the northeast of Borneo have been identified as a promising archaeological site for learning about the early humans that dwelled in this region.

Curnoe and colleagues examined three human mandibles that were previously excavated from the West Mouth of the Niah Cave in 1957. Using Uranium-series dating techniques, the researchers estimate that one of the mandibles is 28-30,000 years old, while the other two are at least 11,000 and 10,000 years old, respectively. The oldest mandible of the three was smaller and more robust compared to other Late Pleistocene mandibles, and this may suggest that it was subject to strain that could have been caused by consuming tough or dried meats or palm plants, a diet that has previously been identified in the Niah Caves.

The researchers suggest that their study helps provide insight into the diet of ancient people living near tropical rainforests, a region which has been previously identified as facing economic difficulties. Through their potential consumption of raw plant foods and dried meats, the hunter-gatherer populations living in this region around the Late Pleistocene may have been adapting to their economically challenging environment.

“These early modern humans were seemingly adapted to a difficult life in the tropical rainforests with their very small bodies and ruggedly built jaws from chewing really tough foods,” says Curnoe. “They tell us a lot about the challenges faced by the earliest people living in island Southeast Asia.”


Two human jaws from Niah Caves in Borneo found in 1958 but only just revealed. Top jaw is 30,000 years old, bottom jaw 11,000 years old; left image is Niah Caves archaeological site where they were both found. Darren Curnoe


Article Source: PLOS news release



Easter Islanders used rope, ramps to put giant hats on famous statues

BINGHAMTON UNIVERSITY—The ancient people of Easter Island, or Rapa Nui, were able to move massive stone hats and place them on top of statues with little effort and resources, using a parbuckling technique, according to new research from a collaboration that included investigators from Binghamton University, State University at New York.

“Of the many questions that surround the island’s past, two tend to stand out: How did people of the past move such massive statues (moai) and how did they place such massive stone hats (pukao) on top of their heads?” said Carl Lipo, a professor of anthropology at Binghamton University.

Pukao are cylinders made of red scoria, some of which weigh up to 12 metric tons. They were moved all around the island, across long distances, with few people and resources.

“We’ve learned they moved the statues in a walking fashion using simple, physics-based processes, in a way that was elegant and remarkably effective,” said Lipo. “Our latest study now tackles the issue of the hats (pukao). These multi-ton stone objects were carved at a separate quarry, transported across the island and somehow raised to the top of the heads of the statues.”

The team took photos of different pukao and used them to generate three-dimensional models that document details that are important for identifying the most likely method of pukao transport.

“The number of possible pukao emplacement methods is limited only by the human imagination,” says Sean Hixon, lead author and current graduate student at Penn State University. “Examples of past ideas for pukao transport include sliding the pukao up a wooden ramp or gradually building a pile of stones beneath the pukao. The challenge is to move beyond merely possible transport methods and to identify a transport scenario that is consistent with variation in the archaeological record.”

“We expect that part of the shapes of pukao will reflect the physical constraints associated with transport” explains Hixon. “Different possible transport methods constrain aspects of pukao variability in different ways.”

Lipo continues, “The answer, like that of our findings with the moai, show that Rapa Nui people were remarkably ingenious and found solutions that required the fewest resources and smallest effort to achieve their goals.”

Their analysis* showed that the pukao were most likely rolled from the quarry to the location of the moai, and rolled up large ramps using a parbuckling technique.

“In parbuckling, a line would have been wrapped around the pukao cylinder, and then people would have pulled the rope from the top of the platform,” said Lipo. “This approach minimizes the effort needed to roll the statue up the ramp. Like the way in which the statues were transported, parbuckling was a simple and elegant solution that required minimum resources and effort.”

Lipo also said that this use of resources shows how efficiently the people of Easter Island used their resources, which contrasts with what was previously thought.

“Easter Island is often treated as a place where prehistoric people acted irrationally, and that this behavior led to a catastrophic ecological collapse,” said Lipo. “The archaeological evidence, however, shows us that this picture is deeply flawed and badly misrepresents what people did on the island, and how they were able to succeed on a tiny and remote place for over 500 years.”

Lipo said he plans to continue researching the Rapa Nui people, and their relationship with their environment and community.

“Our analysis of pukao adds significantly to this new understanding of the island: Rapa Nui people made remarkable achievements through their ingenuity,” said Lipo. “These efforts were embedded in a sustainable social system in which monument construction (such as the pukao) played a vital role. While the social systems of Rapa Nui do not look much like the way our contemporary society functions, these were quite sophisticated people who were well-tuned to the requirements of living on this island and used their resources wisely to maximize their achievements and provide long-term stability.”


This is a restored statue platform with standing moai on the south coast of Rapa Nui. Note that one of the moai is adorned with a red scoria pukao. Sean Hixon


Standing moai adorned with a red scoria pukao. Sean Hixon


This is a diagram of pukao emplacement scenario that is supported by analysis of pukao form and the physics associated with pukao transport. Sean Hixon


*”The Colossal Hats (Pukao) of Monumental Statues on Rapa Nui (Easter Island, Chile): Analysis of Pukao Variability, Transport, and Emplacement,” was published in the Journal of Archaeological Sciences.

Article Source: Binghamton University news release


On the origins of agriculture, researchers uncover new clues

COLORADO STATE UNIVERSITY—The invention of agriculture changed humans and the environment forever, and over several thousand years, the practice originated independently in a least a dozen different places. But why did agriculture begin in those places, at those particular times in human history?

Using a new methodological approach, researchers at Colorado State University and Washington University in St. Louis have uncovered evidence that underscores one long-debated theory: that agriculture arose out of moments of surplus, when environmental conditions were improving, and populations lived in greater densities.

The first-of-its-kind study, “Hindcasting global population densities reveals forces enabling the origin of agriculture,” published in Nature Human Behaviour, lends support to existing ideas about the origins of human agriculture. In contrast, they found little support for two other, longstanding theories: One, that during desperate times, when environmental conditions worsened and populations lived at lower densities, agriculture was born out of necessity, as people needed a new way of getting food. And two, that no general pattern exists, but instead the story of agriculture’s origins is tied to unique social and environmental conditions in each place.

Senior author Michael Gavin, an associate professor in CSU’s Department of Human Dimensions of Natural Resources, said the findings and the general methodological approach may help explain other watershed events in human history.

“There have been several key threshold events in our history that changed the entire course of our species,” Gavin said. “Agriculture is a link to so many other components for what the world is like today for billions of people. This begins to help us explain a key moment in human history.”

Predicting into the past

Studying the depths of human history is challenging, as little data are available when looking back tens of thousands of years. Scientists typically rely on archeological evidence, but getting a broad picture is difficult, since archeological digs cover relatively small areas.

To overcome these limitations, the researchers modeled correlations between the environment, cultural traits and population densities of relatively recent foraging societies, which used hunting, fishing and gathering to obtain food.

Among the factors they considered as possible predictors of population density: environmental productivity; environmental stability; the average distance travelled when people in a community moved to a new location; whether people owned land or other resources; and distance to the nearest coast.

This model, the team found, did a remarkably good job at predicting recent population densities, which led the researchers to pair the model with data on past climate. In doing so, they could hindcast, or predict into the past, the potential population density of the entire globe dating back thousands of years.

Population maps

This study was the first to produce maps of potential population densities dating back as far as 21,000 years. The researchers used these maps to examine conditions that existed in each of the 12 centers of origin, at the point in time agricultural practices began.

Patrick Kavanagh, a CSU postdoctoral scientist and one of the study’s lead authors, said the different centers of origin for agriculture all showed improving environmental conditions and increasing population densities.

“All regions that developed agriculture showed the same pattern,” he said.

Researchers believe that improving environmental conditions may have allowed people the luxury of tinkering with new ideas, and that having more people living in one place would allow ideas to be shared and honed, with sparks of innovation following.

While the researchers found commonalities in the surplus aspect of what was occurring in different locations, that doesn’t mean the exact same conditions existed in each center of origin. Socially, the places and people studied were probably very different. In addition, the timing of when agriculture began in these major centers varied over thousands of years, and the species of plants they were working with was different.

But, amazingly, although the centers of origin varied in time by thousands of years and ranged from the New Guinea Highlands to Central America and the Middle East, they all had one thing in common: improving environmental conditions, and the potential for higher population densities.

“In all of these major origin centers of agriculture, there were some critical environmental changes that needed to occur,” Kavanagh added. “Environmental conditions needed to improve — which we saw in all 12 centers of origin — despite variation in the timing and the diverse geographic locations in which they occurred.”

The research team is now exploring other applications for the maps they produced.

“It is amazing to examine these maps of the potential population density of the world dating back tens of thousands of years,” said Gavin. “We could potentially create them going back to the dawn of our species. This provides a new tool to explore many unanswered questions about human history.”


Ancient stone axe that was used in agriculture. John Eisele/ Colorado State University


Researchers used maps to examine conditions that existed in each of the 12 centers of origin, at the point in time agricultural practices began. Joe A. Mendoza/Colorado State University


‘Agriculture is a link to so many other components for what the world is like today for billions of people,’ said senior author Michael Gavin, an associate professor at Colorado State University. ‘This begins to help us explain a key moment in human history.’ John Eisele/Colorado State University


Article Source: Colorado State University news release


Two genetic stories of human migration into Iceland and the Americas

AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE—Two separate studies – both benefiting from ancient DNA – paint detailed pictures of the founding, migration, and evolution of human populations in Iceland and the Americas, respectively.

More broadly, the plethora of historical information from ancient DNA studies such as these represents a new era of archaeogenomics, say Alessandro Achilli and colleagues in a related Perspective. The ability to study the founding of a human population and its subsequent evolutionary history is rare, but here, S. Sunna Ebenesersdóttir and colleagues were able to make progress on this, providing detailed insights into the making of Icelandic populations specifically. The researchers used genome sequencing data from the skeletal remains of 27 ancient Icelanders – the earliest settlers of Iceland, according to radiocarbon dating. Perhaps not unexpectedly since Iceland was peopled in early times by Vikings and enslaved individuals from Norway and the British-Irish Isles, all ancient Icelanders, the authors found, were Norse (Norway and Sweden), Gaelic (Ireland and Scotland), or a mixture. Surprisingly, however, the ancient Icelanders were much more similar to their source populations in Scandinavia and the British-Irish Isles than to modern Icelanders, comparisons with modern European DNA revealed. One explanation for this, the authors hypothesize, is that roughly 1,100 years of genetic drift (or, a change in the frequency of certain genes due to random happenings) have shaped Icelandic populations to what they are today. Intriguingly, the high degree of mixture in the Norse and Gaelic gene pool of ancient Icelanders may account for why modern Icelandic populations are exceptionally good candidates for studies that attempt to associate genes to traits. The high genetic variation resulting from this ancestral mixture is more desirable for genome-wide association studies, compared to more homogenous populations, for which it is difficult to tell which region of DNA causes a specific trait.

The second study by Christiana Scheib et al. explores the genetics of the first people to enter the Americas, providing evidence, through its results, that a deep split in North and South American populations likely occurred not in Beringia, as has been posited, but just south of the ancient Laurentide ice sheet (which covered a large portion of the northern United States, including most of Canada). Scheib and colleagues sequenced 91 genomes of ancient Native American remains predominantly from California and Southwestern Ontario, Canada. They found that ancient Ontarians were most like other ancient Northern Americans as well as modern Algonquian-speaking Native Americans. In contrast, genomes from ancient Californians resembled groups that currently live in Mexico and South America. Based on these findings, the authors reject the emerging theory that the split between Northern and Southern Americans occurred in Beringia, across the Laurentide ice plate, and suggest that a single wave of Ice Age American populations migrated south of the Laurentide ice plate and a genetic split likely occurred after this crossing, at the northwest corner of ancient North America. Notably, the researchers also found both ancient Californian and Ontarian DNA present and mixed throughout Northern and Southern regions. Thus, the authors suggest that there were possible points where the two diverging branches merged either in North America or along the migration route to South America, at least a few thousand years after the initial split.


Skeletal remains of an ancient pre-Christian (<1000 C.E.) Icelandic female. This material relates to a paper that appeared in the 1 June 2018 issue of Science, published by AAAS. The paper, by S.S. Ebenesersdóttir at deCODE Genetics/AMGEN, Inc. in Reykjavik, Iceland, and colleagues was titled, “Ancient genomes from Iceland reveal the making of a human population.” Ivar Brynjolfsson / The National Museum of Iceland


Article Source: AAAS news release


Along Alaska’s Pacific coast, early humans could have migrated to the Americas

AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE—New dating of rocks and reanalysis of animal bones from islands along the shore of southeastern Alaska suggests that a narrow corridor between the Pacific Ocean and the Cordilleran Ice Sheet (CIS) in Alaska may have enabled the migration of humans to the Americas as early as 17,000 years ago. While the data imply that this Pacific coastal corridor – a pathway exposed following deglaciation – was physically and environmentally viable for early human migration to the Americas, the authors say that archeological evidence of human activity is still necessary to confirm that this pathway played an important role in the peopling of the Americas. The Beringia route was widely believed by many in the 20th century to be the course of human migration to the Americas from Asia. Recent analyses, on the other hand, have suggested that early human migration took place approximately 16 thousand years (ka) ago through a deglaciated corridor to the west of the CIS along the North Pacific coast. Yet, whether or not the coastal region’s environmental conditions – such as biological productivity, availability of food resources and the presence or absence of physical barriers – were fit to support humans at that time remains unknown. Here, Alia J. Lesnek and colleagues reconstructed deglaciation using two different proxies. First, they applied 10Beryllium-dating of ten rock surfaces – five perched boulders and five bedrock samples – from three proposed areas: Dall Island, Suemez Island, and Warren Island. Second, they utilized previously published 14Carbon-dated mammal and bird bones found in caves on nearby islands. Their analysis showed that this area was glaciated from around 20 to 17 ka ago and thus not open for human migration. However, the islands were deglaciated after 17 ka ago and hosted robust terrestrial and marine ecosystems that could support humans during southward migration into the Americas.


University at Buffalo Ph.D. candidate Alia Lesnek works at Suemez Island. Jason Briner


Article Source: AAAS news release


Prehistoric teeth dating back 2 million years reveal details on ancient Africa’s climate

UNIVERSITY OF TORONTO, TORONTO, ON (Canada) – New research out of South Africa’s Wonderwerk Cave led by anthropologists at the University of Toronto (U of T) shows that the climate of the interior of southern Africa almost two million years ago was like no modern African environment — it was much wetter.

In a paper published in Nature Ecology & Evolution, lead author Michaela Ecker, a postdoctoral fellow in the Department of Anthropology at U of T, alongside an international team of scientists that included Michael Chazan, director of U of T’s Archaeology Center, recreated the environmental change in the interior of southern Africa over a span of almost two million years.

“The influence of climatic and environmental change on human evolution is largely understood from East African research,” said Ecker. “Our research constructed the first extensive paleoenvironmental sequence for the interior of southern Africa using a combination of methods for environmental reconstruction at Wonderwerk Cave.”

While East African research shows increasing aridity and the spread of grasslands, the study showed that during the same time period, southern Africa was significantly wetter and housed a plant community unlike any other in the modern African savanna — which means human ancestors were living in environments other than open, arid grasslands.

Using carbon and oxygen stable isotope analysis on the teeth of herbivores excavated from the cave, Ecker and her team were able to reconstruct the vegetation from the time the animal was alive and gain valuable insight into the environmental conditions our human ancestors were living in.

“Understanding the environment humans evolved in is key to improving our knowledge of our species and its development,” said Ecker. “Our work at Wonderwerk Cave demonstrates how humankind existed in multiple environmental contexts in the past — contexts which are substantially different from the environments of today.”

This is the latest U of T research out of Wonderwerk Cave, a massive excavation site in the Kuruman Hills of the Northern Cape Province of South Africa. Chazan has previously discovered early evidence of fire by human ancestors, as well as the earliest evidence of cave-dwelling human ancestors, based on excavations carried out by South African archaeologist Peter Beaumont. Research to date has established a chronology for human occupation of the front of the cave stretching back two million years.

The findings are described in the study “The palaeoecological context of the Oldowan-Acheulean in southern Africa”, published this month in Nature Ecology & Evolution. Research funding was provided by the Social Sciences and Humanities Research Council of Canada, the German Academic Exchange Service, the University of Oxford’s Boise Fund Trust and the Quaternary Research Association. Other team members include James Brink and Lloyd Rossouw of the National Museum, Bloemfontein, Liora Horwitz of the Hebrew University of Jerusalem and Julia Lee-Thorp of the University of Oxford.

Research at Wonderwerk Cave is carried out in collaboration with the McGregor Museum, Kimberley and under permit from the South African Heritage Resources Agency.


A view of southern African landscape as seen from entrance of Wonderwerk Cave. Michaela Ecker


Entrance of Wonderwerk Cave, South Africa. Michaela Ecker


View into excavation area from Wonderwerk Cave entrance. Michaela Ecker


Article Source: University of Toronto news release


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Aerial imagery aids Jerash archaeology

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES—Researchers report* that a combination of historical aerial imagery and modern airborne laser scanning (ALS) helped locate and contextualize archaeological features at risk of destruction in the ancient Jordanian city of Jerash. Rapid development of cities in the Middle East can endanger archaeological sites, which are abundant in the region and susceptible to irreversible damage that could hamper understanding of how ancient societies responded to economic or environmental change. David Stott and colleagues used historical aerial imagery of the city of Jerash in Jordan dating back to 1917 as well as modern ALS data to establish the locations of archaeological structures. Specifically, the authors used historical imagery to identify likely sites and structures and ALS imagery to assess structures remaining in the wake of development in the eastern half of the city. The authors report a substantial number of previously unmapped possible structures and refine the position of the city’s walls and the scale of previously identified structures, compared with earlier maps. The combined ALS and historical imagery suggests connections between aqueducts, cisterns, and siphons that provide insight into the structure of the water supply system for the ancient city. According to the authors, similar historical and modern remote sensing methods can help uncover and evaluate archaeological data.


These are aerial photographs from 1953 (left) and 2015 (right) showing rapid growth in Jerash, particularly in the eastern part of the city and much of its immediate surroundings. PNAS


These are elements of water infrastructure mapped in this study, showing likely aqueducts, channels, springs and cisterns in relation to possible areas of supply within the city. PNAS


Article Source: A PNAS news release

*”Mapping an ancient city with a century of remotely sensed data,” by David Stott, Søren Kristiansen, Achim Lichtenberger, and Rubina Raja.

ULB archaeologists discover a 1,000-year-old mummy in Peru

UNIVERSITÉ LIBRE DE BRUXELLES—A team from the Université libre de Bruxelles’s center for archaeological research (CReA-Patrimoine) has completed a significant excavation in Pachacamac, Peru, where they have discovered an intact mummy in especially good condition. Pachacamac’s status as a Pre-Colombian pilgrimage site under the Inca empire is confirmed by further evidence.

Peter Eeckhout and his team’s latest campaign of archaeological excavations has concluded with an exciting surprise: after nine weeks spent exploring the Pre-Colombian site of Pachacamac, in Peru, the researchers from CReA-Patrimoine (ULB Faculty of Philosophy and Social Sciences) have unearthed a mummy in especially good condition. ‘The deceased is still wrapped in the enormous funeral bundle that served as a coffin,’ points out professor Peter Eeckhout. ‘Discoveries like this one are exceptionally scarce, and this mummy is incredibly well preserved. Samples were collected for carbon-14 dating, but the area in which it was discovered and the type of tomb suggest this individual was buried between 1000 and 1200 AD.’

The excavation was carried out as a part of the ‘Ychsma’ project, named after the region’s native people, under the supervision of professor Eeckhout. Three monumental structures were explored during the campaign, including a sanctuary dedicated to the local ancestors. Under Inca rule, in the late 15th century, it appears to have been transformed into a water and healing temple. The archaeologists have discovered many offerings left by worshippers, such as Spondylus shells imported from Ecuador; these are associated with the influx of water during El Niño, and they symbolize fertility and abundance.

Before the Inca settled in the area, the sanctuary included large funerary chambers and numerous mummies, most of which were looted during the Spanish conquest. Miraculously, though, one of the chambers was found intact during the latest round of excavations: this is the funeral chamber that held the mummy. Due to how well it was preserved, the researchers will be able to study it without needing to unwrap the bundle. Together with Christophe Moulherat (Musée du Quai Branly, Paris), they will soon examine the mummy using the latest techniques in medical imaging (X-ray scans, axial tomography, 3D reconstruction, etc.). This will enable them to determine the individual’s position, any pathologies they might have suffered from, but also what offerings might be inside the bundle.

The other structures that were excavated are also related to worship: the first one, an Inca monument intended to host pilgrims and rituals, was built in several phases, each identified with a series of offerings such as seashells and precious objects. The last structure explored was probably one of the ‘chapels’ for foreign pilgrims, referred to by Spanish monk Antonio de la Calancha in his 17th-century description of the site. There, the excavations also uncovered many ‘foundation’ offerings, including vases, dogs, and other animals, as well as a platform with a hole in the center, where an idol was likely placed. The complex appears to have been designed around this idol, involved in religious activities with pilgrims.

According to researchers, all these discoveries indicate that Incas made considerable changes to the Pachacamac site, in order to create a large pilgrimage center on Peru’s Pacific coast. ‘Deities and their worship played a major part in the life of Pre-Colombian societies,’ concludes Peter Eeckhout. ‘The Inca understood this very well, and integrated it into how they wielded their power. By promoting empire-wide worship, they contributed to creating a common sense of identity among the many different peoples that made up the empire. Pachacamac is one of the most striking examples of this.’


Above and below: The Pachacamac mummy 2018. ULB P. Eeckhout



Article Source: UNIVERSITÉ LIBRE DE BRUXELLES news release


‘Uniquely human’ muscles have been discovered in apes

FRONTIERS—Muscles once thought ‘uniquely human’ have been discovered in several ape species, challenging long-held theories on the origin and evolution of human soft tissues. The findings question the anthropocentric view that certain muscles evolved for the sole purpose of providing special adaptations for human traits, such as walking on two legs, tool use, vocal communication and facial expressions. Published in Frontiers in Ecology and Evolution, the study* highlights that thorough knowledge of ape anatomy is necessary for a better understanding of human evolution.

“This study contradicts key dogmas about human evolution and our distinct place on the ‘ladder of nature,'” says Rui Diogo, an Associate Professor in the Department of Anatomy at Howard University, Washington, USA. “Our detailed analysis shows that in fact, every muscle that has long-been accepted as ‘uniquely human’ and providing ‘crucial singular functional adaptations’ for our bipedalism, tool use and vocal and facial communications is actually present in the same or similar form in bonobos and other apes, such as common chimpanzees and gorillas.”

Long-standing evolutionary theories are largely based on the bone structures of prehistoric specimens — and, according to Diogo, also on the idea that humans are necessarily more special and complex than other animals. These theories suggest that certain muscles evolved in humans only, giving us our unique physical characteristics. However, verification of these theories has remained difficult due to scant descriptions of soft tissues in apes, which historically have mainly focused on only a few muscles in the head or limbs of a single specimen.

Diogo explains, “There is an understandable difficulty in finding primate, and particularly ape, specimens to dissect as they are so rare both in the wild and museums.”

To find enough data to complete this research, Diogo compiled all previous information on ape anatomy based on studies with colleague Bernard Wood. He also conducted anatomical research on several bonobos that died of natural causes, together with colleagues at the University of Antwerp under the Bonobo Morphology Initiative 2016 — looking for the presence of seven different muscles thought to have evolved only in our species.

Diogo discovered that these seven muscles were present in apes in a similar or even exact form. For example the fibularis tertius muscle, said to be uniquely associated with human bipedalism (walking on two legs), was present in half the examined bonobos. Similarly, both the laryngeal muscle arytenoideus obliquus and the facial muscle risorius — thought to have evolved for our uniquely sophisticated vocal and facial communication, respectively — were present in at least some chimpanzees and/or gorillas.

These findings open crucial new directions for research and question our understanding of human evolution. “The picture emerging from this research is that the origin and evolution of human soft-tissue is clearly more complex — and not as exceptional — as first thought,” says Diogo.

“We need a more thorough examination of why these muscles are present in apes and, in some cases, in just part of a population within a certain species,” he says. “Are these muscles essential for the apes that have them, as adaptationist evolutionary scientists would argue? Or are they evolutionary neutral features related to how their bodies develop, or simply by-products of other features?”

He concludes, “Most theories of human evolution give the impression that humans are markedly distinct from apes anatomically, but these are unverifiable ‘just-so stories’. The real evidence shows we are not so different overall. This study highlights that a thorough knowledge of ape anatomy is necessary for a better understanding of our own bodies and evolutionary history.”


Figure showing the striking similarities between the head muscles of common chimpanzees, bonobos and humans: the very rare exceptions are those shown in colors and with text. Rui Diogo


Article Source: A Frontiers news release


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Study: Ancient mound builders carefully timed their occupation of coastal Louisiana site

UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN—CHAMPAIGN, Ill. — A study of ancient mound builders who lived hundreds of years ago on the Mississippi River Delta near present-day New Orleans offers new insights into how Native peoples selected the landforms that supported their villages and earthen mounds – and why these sites were later abandoned.

The study, reported in the Journal of Island and Coastal Archaeology, also offers a timeline of the natural and human events that shaped one particular site, said University of Illinois anthropology professor Jayur Mehta, who conducted the work with Vanderbilt University postdoctoral researcher Elizabeth Chamberlain while both were at Tulane University in New Orleans.

The site, now known as Grand Caillou, is one of hundreds of mound sites in coastal Louisiana, Mehta said. (Watch a video about the research and history of the site.)

“Louisiana is incredibly important in the history of ancient mound-building cultures,” he said. “In what is now the United States, earthen monument and mound construction began on the Louisiana coast.”

Ancient peoples began building mounds in North America as early as 4,500 B.C., Mehta said. They often situated their mounds near resource-rich waterways, which could support larger human settlements. As many as 500 people lived at Grand Caillou in its heyday. Some mounds also served ceremonial functions.

That so many mound sites have survived in coastal Louisiana is a testament to their careful construction, Mehta said. Neglect, however, and coastal subsidence – the result of engineered changes to the flow of the Mississippi River – are wearing away at the mounds.

“Louisiana loses about two ancient mounds and/or Native American villages a year,” Mehta said.

The researchers used a variety of methods – sediment coring, radiocarbon dating, carbon-isotope analysis, the dating of ceramics found onsite and a method called optically stimulated luminescence – to figure out how and when the land underneath the Grand Caillou mound was formed by natural forces and when the mound builders arrived and established their settlement.

“We wanted to understand at a deeper level how Indigenous peoples of the coast were choosing where to build their villages,” Mehta said.

Grand Caillou is situated on a natural levee of the Lafourche sub-delta, one of several major lobes of the Mississippi River Delta near New Orleans. Fed by sediments deposited by the river, Lafourche expanded in size over a period of several hundred years, a process that ended at about 800 A.D., the researchers found. The mound builders set up their village around 1200 A.D., long after the site was stable and covered over with vegetation, the team found.

Core samples and excavations revealed that the mound was built in distinct layers, with clay on the bottom, looser sediments piled in the middle and a clay cap on top. This finding confirms earlier archaeological reports that ancient mounds were engineered in layers to withstand the elements.

“The way they were constructed contributes to their durability,” Mehta said.

The Grand Caillou mound was built on top of a river deposit that was naturally higher than surrounding land.

“It’s only a few feet higher than nearby areas,” Mehta said. “But in a landscape where there’s no topography, one or two feet can make a world of difference.”

Ceramics found at the site date to between 1000 and 1400 A.D. Radiocarbon dating of charcoal found evidence that the site was abandoned by about 1400. By looking at ratios of carbon isotopes – carbon atoms with differing masses – the team saw changes over time that were likely the result of saltwater incursion into the area. These changes coincided with the ultimate abandonment of the village site.

The new study is a much-needed addition to research on threatened cultural sites in coastal regions, said University of Tennessee anthropology professor David G. Anderson, an expert on U.S. Paleoindian archaeology who was not involved in the research.

“We are facing the loss of much of the record of human settlement and use of coastal zones – and must take steps to address the challenge,” Anderson said. “Mehta and Chamberlain’s study exemplifies the kind of work that will be needed.”


The mound at Grand Caillou. Jayur Mehta


Hundreds of ancient mound sites, depicted here with yellow triangles, still survive in coastal Louisiana. A new study teases out the natural and human history of one of these mound-top villages, a site known as Grand Caillou, shown in red. Julie McMahon after Mehta and Chamberlain


*”Mound construction and site selection in the Lafourche subdelta of the Mississippi River delta, Louisiana, USA” is available online and from the U. of I. News Bureau.


Archaeological finds illuminate Roman Empire battle

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES—Archaeological excavations in Denmark shed fresh light on a fierce battle in Northern Europe in the first century AD, according to a study. The Northern expansion of the Roman Empire between first century BC and first century AD was marked by pitched battles with Germanic tribes whose ferocity was a frequent subject of Roman military lore. However, a dearth of well-preserved human remains at purported battle sites has hampered understanding of the nature of the fighters, weaponry, and battlefield practices. Mette Løvschal and colleagues report the results of archaeological excavations undertaken between 2009 and 2014 at Alken Enge wetlands in Denmark’s Illerup River Valley. Dispersed in peat and lake sediments over 75 hectares of wetland meadows, nearly 2,100 human bones and bone fragments were unearthed and radiocarbon-dated to 2 BC-AD 54. Along with weapons, such as spearheads, sword and shield fragments, iron knives, and an axe, the human remains were accompanied by ceramic pots as well as bones and bone fragments of dogs, pigs, and cattle. The human bone fragments, which represent 82 individuals, mostly adult male, bear signs of trauma before and around the time of death as well as tooth marks and fissures caused by foxes, dogs, and wolves. Together, the evidence at Alken Enge suggests large-scale armed conflict by an estimated population of around 380 young men, who sustained combat injuries, lending support to previous accounts of military prowess in northern Germania. The discovery of cut marks on bones, bone assemblages, and hip bones threaded on a stick suggests that human bones may have been collected and treated in the battle’s aftermath, hinting at the possibility of ritual in the disposal of human remains, according to the authors.


Four ossa coxae threaded onto a stick. PNAS


Find assemblages of femur, tibia and fibula, and two small stones. PNAS


Article Source: PNAS news release

*”Direct evidence of a large Northern European Roman period martial event and post-battle corpse manipulation,” by Mads Holst et al.


Far from special: Humanity’s tiny DNA differences are ‘average’ in animal kingdom

HUMAN EVOLUTION—Researchers report* important new insights into evolution following a study of mitochondrial DNA from about 5 million specimens covering about 100,000 animal species.

Mining “big data” insights from the world’s fast-growing genetic databases and reviewing a large literature in evolutionary theory, researchers at The Rockefeller University in New York City and the Biozentrum at the University of Basel in Switzerland, published several conclusions today in the journal Human Evolution. Among them:

  • In genetic diversity terms, Earth’s 7.6 billion humans are anything but special in the animal kingdom. The tiny average genetic difference in mitochondrial sequences between any two individual people on the planet is about the same as the average genetic difference between a pair of the world’s house sparrows, pigeons or robins. The typical difference within a species, including humans, is 0.1% or 1 in 1,000 of the “letters” that make up a DNA sequence.
  • Genetic variation – the average difference in mitochondria DNA between two individuals of the same species – does not increase with population size. Because evolution is relentless, however, the lack of genetic variation offers insights into the timing of a species’ emergence and its maintenance.
  • The mass of evidence supports the hypothesis that most species, be it a bird or a moth or a fish, like modern humans, arose recently and have not had time to develop a lot of genetic diversity. The 0.1% average genetic diversity within humanity today corresponds to the divergence of modern humans as a distinct species about 100,000 – 200,000 years ago – not very long in evolutionary terms. The same is likely true of over 90% of species on Earth today.
  • Genetically the world “is not a blurry place.” Each species has its own specific mitochondrial sequence and other members of the same species are identical or tightly similar. The research shows that species are “islands in sequence space” with few intermediate “stepping stones” surviving the evolutionary process.

Among 1st “big data” insights from a growing collection of mitochondrial DNA

“DNA barcoding” is a quick, simple technique to identify species reliably through a short DNA sequence from a particular region of an organism. For animals, the preferred barcode regions are in mitochondria – cellular organelles that power all animal life. (See also

The new study, “Why should mitochondria define species?” relies largely on the accumulation of more than 5 million mitochondrial barcodes from more than 100,000 animal species, assembled by scientists worldwide over the past 15 years in the open access GenBank database maintained by the US National Center for Biotechnology Information.

The researchers have made novel use of the collection to examine the range of genetic differences within animal species ranging from bumblebees to birds and reveal surprisingly minute genetic variation within most animal species, and very clear genetic distinction between a given species and all others.

“If a Martian landed on Earth and met a flock of pigeons and a crowd of humans, one would not seem more diverse than the other according to the basic measure of mitochondrial DNA,” says Jesse Ausubel, Director of the Program for the Human Environment at The Rockefeller University, where the research was led by Senior Research Associate Mark Stoeckle and Research Associate David Thaler of the University of Basel, Switzerland.

“At a time when humans place so much emphasis on individual and group differences, maybe we should spend more time on the ways in which we resemble one another and the rest of the animal kingdom.”

Says Dr. Stoeckle: “Culture, life experience and other things can make people very different but in terms of basic biology, we’re like the birds.”

“By determining the genetic variety within species of the animal kingdom, made possible only recently by the burgeoning number of DNA sequences, we’ve documented the absence of human exceptionalism.”

Says. Dr. Thaler: “Our approach combines DNA barcodes, which are broad but not deep, from the entire animal kingdom with more detailed sequence information available for the entire mitochondrial genome of modern humans and a few other species. We analyzed DNA barcode sequences from thousands of modern humans in the same way as those from other animal species.”

“One might have thought that, due to their high population numbers and wide geographic distribution, humans might have led to greater genetic diversity than other animal species,” he adds. “At least for mitochondrial DNA, humans turn out to be low to average in genetic diversity.”

“Experts have interpreted low genetic variation among living humans as a result of our recent expansion from a small population in which a sequence from one mother became the ancestor for all modern human mitochondrial sequences,” says Dr. Thaler.

“Our paper strengthens the argument that the low variation in the mitochondrial DNA of modern humans also explains the similar low variation found in over 90% of living animal species – we all likely originated by similar processes and most animal species are likely young.”

Genetic variation does not increase with population

The study results represent a surprise given predictions found in textbooks, and based on mathematical models of evolution, that the bigger the population of a species, the greater the genetic variation one expects to find.

“Is genetic diversity related to the size of the population?” asks Dr. Stoeckle. “The answer is no. The mitochondrial diversity within 7.6 billion humans or 500 million house sparrows or 100,000 sandpipers from around the world is about the same.”

The paper notes, however, that evolution is relentless, that species are always changing, and, therefore, the degree of variation within a given species offers a clue into how long ago it emerged distinctly — in other words, the older the species the greater the average genetic variation between its members.

Evolutionary bottlenecks: the fresh new beginning of a species

While asteroids and ice ages have played major roles in evolutionary history, scientists speculate that another great driver may have been the microbial world, notably viruses, which periodically cull populations, leaving behind only those able to survive the deadly challenge.

“Life is fragile, susceptible to reductions in population from ice ages and other forms of environmental change, infections, predation, competition from other species and for limited resources, and interactions among these forces,” says Dr. Thaler. Adds Dr. Thaler, “The similar sequence variation in many species suggests that all of animal life experiences pulses of growth and stasis or near extinction on similar time scales.”

“Scholars have previously argued that 99% of all animal species that ever lived are now extinct. Our work suggests that most species of animals alive today are like humans, descendants of ancestors who emerged from small populations possibly with near-extinction events within the last few hundred thousand years.”

‘Islands in sequence space’

Another intriguing insight from the study, says Mr. Ausubel, is that “genetically, the world is not a blurry place. It is hard to find ‘intermediates’ – the evolutionary stepping stones between species. The intermediates disappear.”

Dr. Thaler notes: “Darwin struggled to understand the absence of intermediates and his questions remain fruitful.”

“The research is a new way to show that species are ‘islands in sequence space.’ Each species has its own narrow, very specific consensus sequence, just as our phone system has short, unique numeric codes to tell cities and countries apart.”

Adds Dr. Thaler: “If individuals are stars, then species are galaxies. They are compact clusters in the vastness of empty sequence space.”

The researchers say that with the bones or teeth of an ancient hominid, like those found in southern France or northern Spain, scientists might shed further light on the rate of evolution of the human species.

“It would be very exciting if over the next few years physical anthropologists and others were able to compare mitochondrial DNA from hominid species over the last 500,000 years,” says Dr. Stoeckle.


Today’s study, “Why should mitochondria define species?” published as an open-access article (DOI: 10.14673/HE2018121037) in the journal Human Evolution, builds on earlier work by Drs. Stoeckle and Thayer, including an examination of the mitochondrial genetic diversity of humans vs. our closest living and extinct relatives. The amount of color variation within each red box of the Klee diagram illustrates the far greater mitochondrial diversity among chimpanzees and bonobos than among living humans. (From the journal Ecology and Evolution, online at The Rockefeller University


The study results represent a surprise given predictions found in textbooks, and based on mathematical models of evolution, that the bigger the population of a species, the greater the genetic variation one expects to find. In fact, the mitochondrial diversity within 7.6 billion humans or 500 million house sparrows or 100,000 sandpipers from around the world is about the same. The paper notes, however, that evolution is relentless, that species are always changing, and, therefore, the degree of variation within a given species offers a clue into how long ago it emerged distinctly — in other words, the older the species the greater the average genetic variation between its members. The Rockefeller University


Genetically, ‘the world is not a blurry place.’ It is hard to find ‘intermediates’ — the evolutionary stepping stones between species. The intermediates disappear. The research is a new way to show that species are ‘islands in sequence space.’ Each species has its own narrow, very specific consensus sequence, just as our phone system has short, unique numeric codes to tell cities and countries apart. The Rockefeller University


Article Source: Journal of Human Evolution news release


Scientists analyze first ancient human DNA from Southeast Asia

HARVARD MEDICAL SCHOOL—The first whole-genome analyses of ancient human DNA from Southeast Asia reveal that there were at least three major waves of human migration into the region over the last 50,000 years.

The research, published online May 17 in Science, complements what is known from archaeological, historical and linguistic studies of Southeast Asia, defined as the area east of India and south of China.

The work illuminates another critical portion of the story of ancient population dynamics around the world, joining numerous ancient-DNA studies of Europe as well as burgeoning research from the Near East, Central Asia, Pacific Islands and Africa.

“A very important part of the world is now accessible for ancient DNA analysis,” said Mark Lipson, a postdoctoral fellow in the lab of ancient-DNA specialist David Reich at Harvard Medical School and first author of the study. “It opens a window into the genetic origins of the people who lived there in the past and those who live there now.”

An international team led by researchers at HMS and the University of Vienna extracted and analyzed DNA from the remains of 18 people who lived between about 4,100 and 1,700 years ago in what are now Vietnam, Thailand, Myanmar and Cambodia.

The team found that the first migration took place about 45,000 years ago, bringing in people who became hunter-gatherers.

Then, during the Neolithic Period, around 4,500 years ago, there was a large-scale influx of people from China who introduced farming practices to Southeast Asia and mixed with the local hunter-gatherers.

People today with this ancestry mix tend to speak Austroasiatic languages, leading the researchers to propose that the farmers who came from the north were early Austroasiatic speakers.

“This study reveals a complex interplay between archaeology, genetics and language, which is critical for understanding the history of Southeast Asian populations,” said co-senior author Ron Pinhasi of the University of Vienna.

The research revealed that subsequent waves of migration during the Bronze Age, again from China, arrived in Myanmar by about 3,000 years ago, in Vietnam by 2,000 years ago and in Thailand within the last 1,000 years. These movements introduced ancestry types that are today associated with speakers of different languages.

The identification of three ancestral populations–hunter-gatherers, first farmers and Bronze Age migrants–echoes a pattern first uncovered in ancient DNA studies of Europeans, but with at least one major difference: Much of the ancestral diversity in Europe has faded over time as populations mingled, while Southeast Asian populations have retained far more variation.

“People who are nearly direct descendants of each of the three source populations are still living in the region today, including people with significant hunter-gatherer ancestry who live in Thailand, Malaysia, the Philippines and the Andaman Islands,” said Reich, professor of genetics at HMS and co-senior author of the study. “Whereas in Europe, no one living today has more than a small fraction of ancestry from the European hunter-gatherers.”

Reich hypothesizes that the high diversity of Southeast Asia today can be partly explained by the fact that farmers arrived much more recently than in Europe–around 4,500 years ago compared with 8,000 years ago–leaving less time for populations to mix and genetic variation to even out.

The new findings make it clear that the multiple waves of migration, each of which occurred during a key transition period of Southeast Asian history, shaped the genetics of the region to a remarkable extent.

“The major population turnover that came with the arrival of farmers is unsurprising, but the magnitudes of replacement during the Bronze Age are much higher than many people would have guessed,” said Reich.

Also unexpected were the linguistic implications raised by analyses of the ancestry of people in western Indonesia.

“The evidence suggests that the first farmers of western Indonesia spoke Austroasiatic languages rather than the Austronesian languages spoken there today,” Reich added. “Thus, Austronesian languages were probably later arrivals.”

Additional samples from western Indonesia before and after 4,000 years ago should settle the question, Reich said.


Field workers excavate ancient human remains at Man Bac, Vietnam, in 2007. DNA from skeletons at this site was included in the current study. Lorna Tilley, Australian National University


Article Source: Harvard Medical School news release

This study was supported by the French Ministry for Europe and Foreign Affairs, Japan Society for the Promotion of Science (grant 16H02527), Statutory City of Ostrava (grant 0924/2016/ŠaS), University of Ostrava (IRP projects), Moravian-Silesian Region (grant 01211/2016/RRC), Irish Research Council (grant GOIPG/2013/36), Thailand Research Fund (grant MRG5980146), Czech Ministry of Education, Youth and Sports (project OPVVV 16_019/0000759), European Research Council starting grant ADNABIOARC (263441), National Science Foundation (HOMINID grant BCS-1032255), National Institutes of Health (NIGMS grant GM100233), Paul Allen Foundation and Howard Hughes Medical Institute.


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Critically endangered South American forests were man made

UNIVERSITY OF EXETER—Critically endangered South American forests thought to be the result of climate change were actually spread by ancient communities, archaeologists have found.

Huge swathes of land in Chile, Brazil and Argentina are covered with millions of Araucaria, or monkey puzzle trees, thanks to people planting or cultivating them more than a thousand years ago, a new study shows. Recent logging means the landscape is now one of the world’s most at-risk environments.

It had been thought the forests expanded due to wetter and warmer weather. But the research shows the rapidly expanding pre-Columbian population of South America, Southern Jê communities, were really responsible.

New excavations and soil analysis shows the forests, still hugely culturally and economically important to people living in South America, expanded between 1,410 and 900 years ago because of population growth and cultural changes.

Dr Mark Robinson, from the University of Exeter, who led the British Academy and AHRC-FAPESP-funded research, said: “Our research shows these landscapes were man-made. Communities settled on grassland, and then – perhaps because they modified the soil, protected seedlings or even planted trees – established these forests in places where geographically they shouldn’t have flourished.”

The forests date back to the period when dinosaurs roamed. The iconic monkey puzzle tree, or Parana pine, has grown in the region for thousands of years. Its nuts were one of the most important food sources for ancient communities, attracted game for hunting when nuts were ripe. They were also a valuable source of timber, fuel and resin, and became an integral part of southern Jê cosmology. Communities still call themselves “people of the Araucaria”, and hold festivals to celebrate the forests.

Of the 19 species of Araucaria tree, five are classified as endangered and two, including the Brazilian Araucaria angustifolia, are critically endangered. Reports from the late 1800s describe trees with diameters of over 2 m, reaching 42 m in height. Modern trees are only around 17.7 m tall.

The archaeological analysis began because the experts, from the University of Exeter, University of Reading, University of São Paulo, University of New Mexico, Universidade Federal de Pelotas and Universidade do Sul de Santa Catarina, noticed that in areas of low human activity forests are limited to south-facing slopes, whereas in areas of extensive archaeology, forests cover the entire landscape. They were able to analyse soil isotopes reflecting vegetation and archaeological evidence from Campo Belo do Sul, Santa Catarina State, Brazil, to test whether this pattern was directly related to past human activity.

The study shows the forests first expanded around 4,480 to 3,200 years ago, most likely near streams, and this may have been caused by a wetter climate. But a more rapid and extensive expansion across the whole region later happened between 1,410 and 900 years ago, when forests expanded into highland areas. The weather during this time was dry and less humid. This expansion of the forests coincides with population growth and increasingly complex and hierarchical societies in South America.

The expansion in forests reached a peak around 800 years ago. The number of people in South America declined 400 years ago when European settlers arrived in the area. The population did not begin to recover until the 19 century, when loggers began exploiting the Araucaria forests for timber.

Professor José Iriarte, from the University of Exeter, another member of the research team, said: “This study shows the Araucaria forests were expanded beyond their natural boundaries, they were used sustainably for hundreds of years, and conservation strategies must reflect this so they balance protection, heritage and economic development.”

Uncoupling human and climate drivers of late Holocene vegetation change in southern Brazil is published in the journal Scientific Reports.


Campos da Serra y Floresta de Araucari. Jose Iriarte


Monkey puzzle forests. Mark Robinson

How our ancestors with autistic traits led a revolution in Ice Age art

UNIVERSITY OF YORK—The ability to focus on detail, a common trait among people with autism, allowed realism to flourish in Ice Age art, according to researchers at the University of York.

Around 30,000 years ago realistic art suddenly flourished in Europe. Extremely accurate depictions of bears, bison, horses and lions decorate the walls of Ice Age archaeological sites such as Chauvet Cave in southern France.

Why our ice age ancestors created exceptionally realistic art rather than the very simple or stylized art of earlier modern humans has long perplexed researchers.

Many have argued that psychotropic drugs were behind the detailed illustrations. The popular idea that drugs might make people better at art led to a number of ethically-dubious studies in the 60s where participants were given art materials and LSD.

The authors of the new study* discount that theory, arguing instead that individuals with “detail focus”, a trait linked to autism, kicked off an artistic movement that led to the proliferation of realistic cave drawings across Europe.

Lead author of the paper, Dr Penny Spikins from the Department of Archaeology at the University of York, said: “Detail focus is what determines whether you can draw realistically; you need it in order to be a talented realistic artist. This trait is found very commonly in people with autism and rarely occurs in people without it.

“We looked at the evidence from studies attempting to identify a link between artistic talent and drug use, and found that drugs can only serve to dis-inhibit individuals with a pre-existing ability. The idea that people with a high degree of detail focus, many of which may have had autism, set a trend for extreme realism in ice age art is a more convincing explanation.”

The research adds to a growing body of evidence that people with autistic traits played an important role in human evolution.

Dr Spikins added: “Individuals with this trait – both those who would be diagnosed with autism in the modern day and those that wouldn’t – likely played an important part in human evolution and survival as we colonised Europe.

“As well as contributing to early culture, people with the attention to detail needed to paint realistic art would also have had the focus to create complex tools from materials such as bone, rock and wood. These skills became increasingly important in enabling us to adapt to the harsh environments we encountered in Europe.”


This is a drawing of a horse by Nadia, a gifted autistic child artist (left) and by a typically developing child of the same age (right). Penny Spikins, University of York


Article Source: University of York news release

*How do we explain ‘autistic traits’ in European Upper Palaeolithic art? is published in Open Archaeology.


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