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PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES—By assembling Bahamian records of landscape, vegetation, and anthropogenic burning via charcoal and pollen samples from the Bahamas’ Blackwood Sinkhole, researchers determined that Lucayans–the first humans to inhabit the Bahamas–arrived in the northern Bahamas around 830 CE and expanded rapidly throughout the Bahamian archipelago in less than a century; although the Bahamas’ forest landscape rapidly transitioned from hurricane-resilient hardwoods and palms to modern pine with the arrival of Lucayans, pine forests decreased during heightened regional hurricane activity in the 16th century, suggesting that future increases in hurricane activity may endanger Bahamian pine forests.

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Aerial photo of Blackwood Sinkhole on Abaco, northern Bahamas. Peter J. van Hengstum

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“Human arrival and landscape dynamics in the northern Bahamas,” by Patricia L. Fall et al.

Article Source: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES news release

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BINGHAMTON UNIVERSITY, BINGHAMTON, NY—Neanderthals—the closest ancestor to modern humans — possessed the ability to perceive and produce human speech, according to a new study published by an international multidisciplinary team of researchers including Binghamton University anthropology professor Rolf Quam and graduate student Alex Velez.

“This is one of the most important studies I have been involved in during my career”, says Quam. “The results are solid and clearly show the Neanderthals had the capacity to perceive and produce human speech. This is one of the very few current, ongoing research lines relying on fossil evidence to study the evolution of language, a notoriously tricky subject in anthropology.”

The evolution of language, and the linguistic capacities in Neanderthals in particular, is a long-standing question in human evolution.

“For decades, one of the central questions in human evolutionary studies has been whether the human form of communication, spoken language, was also present in any other species of human ancestor, especially the Neanderthals,” says coauthor Juan Luis Arsuaga, Professor of Paleontology at the Universidad Complutense de Madrid and co-director of the excavations and research at the Atapuerca sites. The latest study has reconstructed how Neanderthals heard to draw some inferences about how they may have communicated.

The study relied on high resolution CT scans to create virtual 3D models of the ear structures in Homo sapiens and Neanderthals as well as earlier fossils from the site of Atapuerca that represent ancestors of the Neanderthals. Data collected on the 3D models were entered into a software-based model, developed in the field of auditory bioengineering, to estimate the hearing abilities up to 5 kHz, which encompasses most of the frequency range of modern human speech sounds. Compared with the Atapuerca fossils, the Neanderthals showed slightly better hearing between 4-5 kHz, resembling modern humans more closely.

In addition, the researchers were able to calculate the frequency range of maximum sensitivity, technically known as the occupied bandwidth, in each species. The occupied bandwidth is related to the communication system, such that a wider bandwidth allows for a larger number of easily distinguishable acoustic signals to be used in the oral communication of a species. This, in turn, improves the efficiency of communication, the ability to deliver a clear message in the shortest amount of time. The Neanderthals show a wider bandwidth compared with their ancestors from Atapuerca, more closely resembling modern humans in this feature.

“This really is the key,” says Mercedes Conde-Valverde, professor at the Universidad de Alcalá in Spain and lead author of the study. “The presence of similar hearing abilities, particularly the bandwidth, demonstrates that the Neandertals possessed a communication system that was as complex and efficient as modern human speech.”

“One of the other interesting results from the study was the suggestion that Neanderthal speech likely included an increased use of consonants,” said Quam. “Most previous studies of Neanderthal speech capacities focused on their ability to produce the main vowels in English spoken language. However, we feel this emphasis is misplaced, since the use of consonants is a way to include more information in the vocal signal and it also separates human speech and language from the communication patterns in nearly all other primates. The fact that our study picked up on this is a really interesting aspect of the research and is a novel suggestion regarding the linguistic capacities in our fossil ancestors.”

Thus, Neanderthals had a similar capacity to us to produce the sounds of human speech, and their ear was “tuned” to perceive these frequencies. This change in the auditory capacities in Neanderthals, compared with their ancestors from Atapuerca, parallels archaeological evidence for increasingly complex behavioral patterns, including changes in stone tool technology, domestication of fire and possible symbolic practices. Thus, the study provides strong evidence in favor of the coevolution of increasingly complex behaviors and increasing efficiency in vocal communication throughout the course of human evolution.

The team behind the new study has been developing this research line for nearly two decades, and has ongoing collaborations to extend the analyses to additional fossil species. For the moment, however, the new results are exciting.

“These results are particularly gratifying,” said Ignacio Martinez from Universidad de Alcalá in Spain. “We believe, after more than a century of research into this question, that we have provided a conclusive answer to the question of Neanderthal speech capacities.”

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3D model and virtual reconstruction of the ear in a modern human (left) and the Amud 1 Neandertal (right). Mercedes Conde-Valverde

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Reconstructed hearing patterns in modern humans, Neanderthals and the Sima de los Huesos based on their ear anatomy. Compared with their ancestors from the Sima de los Huesos, the Neanderthals more closely resemble modern humans in showing a heightened sensitivity between 3.5-5 kHz, a frequency range that contains acoustic information related to consonant production in human spoken language. Mercedes Conde-Valverde

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The study, “Neandertals and modern humans had similar auditory and speech capacities,” was published in Nature Ecology and Evolution.

Article Source: BINGHAMTON UNIVERSITY news release

UNIVERSITY OF COPENHAGEN – FACULTY OF HUMANITIES—Based on a manual recently discovered in a 3,500-year-old medical papyrus, University of Copenhagen Egyptologist Sofie Schiødt has been able to help reconstruct the embalming process used to prepare ancient Egyptians for the afterlife. It is the oldest surviving manual on mummification yet discovered.

In ancient Egypt, embalming was considered a sacred art, and knowledge of the process was the preserve of very few individuals. Most secrets of the art were probably passed on orally from one embalmer to the other, Egyptologists believe, so written evidence is scarce; until recently, only two texts on mummification had been identified.

Egyptologists were therefore surprised to find a short manual on embalming in a medical text that is primarily concerned with herbal medicine and swellings of the skin. The manual has recently been edited by University of Copenhagen Egyptologist Sofie Schiødt:

– Many descriptions of embalming techniques that we find in this papyrus have been left out of the two later manuals, and the descriptions are extremely detailed. The text reads like a memory aid, so the intended readers must have been specialists who needed to be reminded of these details, such as unguent recipes and uses of various types of bandages. Some of the simpler processes, e.g. the drying of the body with natron, have been omitted from the text, Sofie Schiødt explains. She adds:

– One of the exciting new pieces of information the text provides us with concerns the procedure for embalming the dead person’s face. We get a list of ingredients for a remedy consisting largely of plant-based aromatic substances and binders that are cooked into a liquid, with which the embalmers coat a piece of red linen. The red linen is then applied to the dead person’s face in order to encase it in a protective cocoon of fragrant and anti-bacterial matter. This process was repeated at four-day intervals.

Although this procedure has not been identified before, Egyptologists have previously examined several mummies from the same period as this manual whose faces were covered in cloth and resin. According to Sofie Schiødt, this would fit well with the red linen procedure described in this manuscript.

Four was the key number

The importance of the Papyrus Louvre-Carlsberg manual in reconstructing the embalming process lies in its specification of the process being divided into intervals of four, with the embalmers actively working on the mummy every four days.

– A ritual procession of the mummy marked these days, celebrating the progress of restoring the deceased’s corporeal integrity, amounting to 17 processions over the course of the embalming period. In between the four-day intervals, the body was covered with cloth and overlaid with straw infused with aromatics to keep away insects and scavengers, Sofie Schiødt says.

The Papyrus Louvre-Carlsberg

The manuscript, which Sofie Schiødt has been working on for her PhD thesis, is the Papyrus Louvre-Carlsberg – so called because one half of the papyrus belongs to the Louvre Museum in Paris and the other half is part of the University of Copenhagen’s Papyrus Carlsberg Collection. The two parts of the papyrus originally belonged to two private collectors, and several sections of it are still missing. Based on the palaeography, that is, the sign forms, the six meter long papyrus is dated to approximately 1450 BC, which means that it predates the only two other examples of embalming texts by more than a thousand years.

The bulk of the papyrus, which is the second-longest medical papyrus surviving from ancient Egypt, deals with herbal medicine and skin illnesses. Specifically, it contains the earliest-known herbal treatise, which provides descriptions of the appearance, habitat, uses, and religious significance of a divine plant and its seed as well as a lengthy treatise on swellings of the skin, which are seen as illnesses sent forth by the lunar god Khonsu.

The papyrus is planned for publication in 2022 as a collaboration between the Louvre Museum and the Papyrus Carlsberg Collection. If you are interested in a copy of Sofie Schiødt’s PhD thesis “Medical Science in Ancient Egypt: A translation and interpretation of Papyrus Louvre-Carlsberg (PLouvre E 32847 + PCarlsberg 917)”, which she defended 8 February 2021, please contact her at zcq348@hum.ku.dk.

The embalming process

The embalming, which was performed in a purpose-built workshop erected near the grave, took place over 70 days that were divided into two main periods – a 35-day drying period and a 35-day wrapping period.

During the drying period, the body was treated with dry natron both inside and outside. The natron treatment began on the fourth day of embalming after the purification of the body, the removal of the organs and the brain, and the collapsing of the eyes.

The second 35-day period was dedicated to the encasing of the deceased in bandages and aromatic substances. The embalming of the face described in the Papyrus Louvre-Carlsberg belonged to this period.

The entire 70-day embalming process was divided into intervals of 4 days, with the mummy being finished on day 68 and then placed in the coffin, after which the final days were spent on ritual activities allowing the deceased to live on in the afterlife.

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The papyrus contains new evidence of the procedure for embalming the deceased’s face, where the face is covered with a piece of red linen and aromatic substances. Ida Christensen, University of Copenhagen

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Section of the papyrus that deals with swellings of the skin. The Papyrus Carlsberg Collection, University of Copenhagen

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Article Source: UNIVERSITY OF COPENHAGEN – FACULTY OF HUMANITIES news release

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TEXAS A&M UNIVERSITY—Evolutionary expert Charles Darwin and others recognized a close evolutionary relationship between humans, chimps and gorillas based on their shared anatomies, raising some big questions: how are humans related to other primates, and exactly how did early humans move around? Research by a Texas A&M University professor may provide some answers.

Thomas Cody Prang, assistant professor of anthropology, and colleagues examined the skeletal remains of Ardipithecus ramidus (“Ardi”), dated to 4.4 million years old and found in Ethiopia. One of Ardi’s hands was exceptionally well-preserved.

The researchers compared the shape of Ardi’s hand to hundreds of other hand specimens representing recent humans, apes and monkeys (measured from bones in museum collections around the world) to make comparisons about the kind of locomotor behavior used by the earliest hominins (fossil human relatives).

The results provide clues about how early humans began to walk upright and make similar movements that all humans perform today.

This discovery is described in a study published in the current issue of Science Advances.

“Bone shape reflects adaptation to particular habits or lifestyles – for example the movement of primates – and by drawing connections between bone shape and behavior among living forms, we can make inferences about the behavior of extinct species, such as Ardi, that we can’t directly observe, Prang said.

“Additionally, we found evidence for a big evolutionary ‘jump’ between the kind of hand represented by Ardi and all later hominin hands, including that of Lucy’s species (a famous 3.2 million-year-old well-preserved skeleton found in the same area in the 1970s). This ‘evolutionary jump’ happens at a critical time when hominins are evolving adaptations to a more human-like form of upright walking, and the earliest evidence for hominin stone-tool manufacture and stone-tool use, such as cut-marks on animal fossils, are discovered.”

Prang said the fact that Ardi represents an earlier phase of human evolutionary history is important because it potentially shines light on the kind of ancestor from which humans and chimpanzees evolved.

“Our study supports a classic idea first proposed by Charles Darwin in 1871, when he had no fossils or understanding of genetics, that the use of the hands and upper limbs for manipulation appeared in early human relatives in connection with upright walking,” he said. “The evolution of human hands and feet probably happened in a correlated fashion.”

Since Ardi is such an ancient species, it might retain skeletal features that were present in the last common ancestor of humans and chimpanzees. If this is true, it could help researchers place the origin of the human lineage – in addition to upright walking – into a clearer light.

“It potentially brings us one step closer to an explanation for how and why humans evolved our form of upright walking,” Prang said.

He added that the big change in hand anatomy between Ardi and all later hominins occurs at a time, roughly between 4.4 and 3.3 million years ago, coinciding with the earliest evidence of the loss of a grasping big toe in human evolution. This also coincides with the earliest known stone tools and stone cut-marked animal fossils.

He said it appears to mark a major change in the lifestyle and behavior of human relatives within this timeframe.

“We propose that it involves the evolution of more advanced upright walking, which enabled human hands to be modified by the evolutionary process for enhanced manual manipulation, possibly involving stone tools,” Prang said.

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Fossil reconstruction of Ardipithecus ramidus hand. Bjoertvedt, Creative Commons Attribution-Share Alike 4.0 International license, Wikimedia Commons

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Ardipithecus ramidus skull as displayed in the National Museum of Natural Sciences of Spain. Tiia Monto, Creative Commons Attribution-Share Alike 3.0 Unported license, Wikimedia Commons

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Article Source: TEXAS A&M UNIVERSITY news release

This research was funded by the Wenner Gren Foundation.

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UNIVERSITY AT BUFFALO, BUFFALO, N.Y.—The history of dogs has been intertwined, since ancient times, with that of the humans who domesticated them.

But how far back does that history go in the Americas, and which route did dogs use to enter this part of the world?

A new study led by the University at Buffalo provides insight into these questions. The research reports that a bone fragment found in Southeast Alaska belongs to a dog that lived in the region about 10,150 years ago. Scientists say the remains — a piece of a femur — represent the oldest confirmed remains of a domestic dog in the Americas.

DNA from the bone fragment holds clues about early canine history in this part of the world.

Researchers analyzed the dog’s mitochondrial genome, and concluded that the animal belonged to a lineage of dogs whose evolutionary history diverged from that of Siberian dogs as early as 16,700 years ago. The timing of that split coincides with a period when humans may have been migrating into North America along a coastal route that included Southeast Alaska.

The research will be published on Feb. 24 in the Proceedings of the Royal Society B. Charlotte Lindqvist, an evolutionary biologist from UB, was senior author of the study, which included scientists from UB and the University of South Dakota. The findings add to a growing body of knowledge about the migration of dogs into the Americas.

“We now have genetic evidence from an ancient dog found along the Alaskan coast. Because dogs are a proxy for human occupation, our data help provide not only a timing but also a location for the entry of dogs and people into the Americas. Our study supports the theory that this migration occurred just as coastal glaciers retreated during the last Ice Age,” says Lindqvist, PhD, associate professor of biological sciences in the UB College of Arts and Sciences. “There have been multiple waves of dogs migrating into the Americas, but one question has been, when did the first dogs arrive? And did they follow an interior ice-free corridor between the massive ice sheets that covered the North American continent, or was their first migration along the coast?”

“The fossil record of ancient dogs in the Americas is incomplete, so any new remains that are found provide important clues,” says Flavio Augusto da Silva Coelho, a UB PhD student in biological sciences, and one of the paper’s first authors. “Before our study, the earliest ancient American dog bones that had their DNA sequenced were found in the U.S. Midwest.”

A surprise finding from a large collection of bones

Lindqvist’s team did not set out to study dogs. The scientists came across the femur fragment while sequencing DNA from a collection of hundreds of bones excavated years before in Southeast Alaska by researchers including Timothy Heaton, PhD, professor of earth sciences at the University of South Dakota.

“This all started out with our interest in how Ice Age climatic changes impacted animals’ survival and movements in this region,” Lindqvist says. “Southeast Alaska might have served as an ice-free stopping point of sorts, and now — with our dog — we think that early human migration through the region might be much more important than some previously suspected.”

The bone fragment, originally thought to come from a bear, was quite small, but when the DNA was studied, the team realized it was from a dog, Lindqvist says.

After this surprise discovery, the scientists compared the bone’s mitochondrial genome to those of other ancient and modern dogs. This analysis showed that the Southeast Alaskan dog shared a common ancestor about 16,000 years ago with American canines that lived before the arrival of European colonizers, Lindqvist says. (Mitochondrial DNA, inherited from the mother, represents a small fraction of an organism’s complete DNA, so sequencing a complete nuclear genome could provide further details if that material can be extracted.)

Of interest, carbon isotope analysis on the bone fragment indicates that the ancient Southeast Alaskan dog likely had a marine diet, which may have consisted of foods such as fish and scraps from seals and whales.

The research adds depth to the layered history of how dogs came to populate the Americas. As Lindqvist notes, canines did not arrive all at once. For example, some Arctic dogs arrived later from East Asia with the Thule culture, while Siberian huskies were imported to Alaska during the Gold Rush. Other dogs were brought to the Americas by European colonizers.

The new study sharpens the debate on dog and human migration into the Americas.

“Our early dog from Southeast Alaska supports the hypothesis that the first dog and human migration occurred through the Northwest Pacific coastal route instead of the central continental corridor, which is thought to have become viable only about 13,000 years ago,” Coelho notes.

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This bone fragment, found in Southeast Alaska, belongs to a dog that lived about 10,150 years ago, a study concludes. Scientists say the remains, a piece of a femur, provide insight into the question of when dogs and humans first entered the Americas, and what route they took to get there. Douglas Levere / University at Buffalo

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A map showing the study area. Bob Wilder / University at Buffalo

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Flavio Augusto da Silva Coelho, a University at Buffalo PhD student in biological sciences, holds the ancient dog bone fragment that was found in Southeast Alaska. Douglas Levere / University at Buffalo

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Article Source: UNIVERSITY AT BUFFALO news release

The research was funded by the National Science Foundation. In addition to Lindqvist, Coelho and Heaton, authors of the new paper in Proceedings of the Royal Society B included Stephanie Gill and Crystal Tomlin.

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UNIVERSITY OF MELBOURNE—A two-meter-long painting of a kangaroo in Western Australia’s Kimberley region has been identified as Australia’s oldest intact rock painting.

Using the radiocarbon dating of 27 mud wasp nests, collected from over and under 16 similar paintings, a University of Melbourne collaboration has put the painting at 17,500 and 17,100 years old.

“This makes the painting Australia’s oldest known in-situ painting,” said Postdoctoral Researcher Dr Damien Finch who pioneered the exciting new radiocarbon technique.

“This is a significant find as through these initial estimates, we can understand something of the world these ancient artists lived in. We can never know what was in the mind of the artist when he/she painted this piece of work more than 600 generations ago, but we do know that the Naturalistic period extended back into the Last Ice Age, so the environment was cooler and dryer than today.”

The Kimberley-based research is part of Australia’s largest rock art dating project, led by Professor Andy Gleadow from the University of Melbourne. It involves the Balanggarra Aboriginal Corporation, the Universities of Western Australia, Wollongong, and Manchester, the Australian National Science and Technology Organization, and partners Rock Art Australia and Dunkeld Pastoral.

Published today in Nature Human Behaviour, Dr Finch and his colleagues detail how rock shelters have preserved the Kimberley galleries of rock paintings, many of them painted over by younger artists, for millennia – and how they managed to date the kangaroo rock painting as Australia’s oldest known in-situ painting.

The kangaroo is painted on the sloping ceiling of a rock shelter on the Unghango clan estate in Balanggarra country, above the Drysdale River in the north-eastern Kimberley region of Western Australia.

Earlier researchers looked at the stylistic features of the paintings and the order in which they were painted when they overlapped, and were able to work out from there that the oldest style of painting is what’s known as the Irregular Infill Animal or the Naturalistic period, which often features life-size animals. This kangaroo is a typical example of paintings in this style.

Dr Finch said it was rare to find mud wasp nests both overlying and underlying a single painting. For this painting they were able to sample both types to establish the minimum and maximum age for the artwork.

“We radiocarbon dated three wasp nests underlying the painting and three nests built over it to determine, confidently, that the painting is between 17,500 and 17,100 years old; most likely 17,300 years old.”

Dr Sven Ouzman, from University Western Australia’s School of Social Sciences and one of the project’s chief investigators, said the rock painting would unlock further understanding of Indigenous cultural history.

“This iconic kangaroo image is visually similar to rock paintings from islands in South East Asia dated to more than 40,000 years ago, suggesting a cultural link – and hinting at still older rock art in Australia,” Dr Ouzman said.

Cissy Gore-Birch, Chair of the Balanggarra Aboriginal Corporation, said partnerships were important to integrate traditional knowledge with western science, to preserve Australia’s history and cultural identity.

“It’s important that Indigenous knowledge and stories are not lost and continue to be shared for generations to come,” Ms Gore-Birch said. “The dating of this oldest known painting in an Australian rock shelter holds a great deal of significance for Aboriginal people and Australians and is an important part of Australia’s history.”

The next step for the researchers, who are aiming to develop a time scale for Aboriginal rock art in the Kimberley, is to date further wasp nests in contact with this and other styles of Kimberley rock art to establish, more accurately, when each art period began and ended.

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Traditional Owner Ian Waina inspecting a Naturalistic painting of a kangaroo, determined to be more than 12,700 years old based on the age of overlying mud wasp nests. The inset is an illustration of the painting above it. Peter Veth and the Balanggarra Aboriginal Corporation, Illustration: Pauline Heaney

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Article Source: UNIVERSITY OF MELBOURNE news release

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FRONTIERS—Modern medical technology is helping scholars tell a more nuanced story about the fate of an ancient king whose violent death indirectly led to the reunification of Egypt in the 16th century BC. The research was published in Frontiers in Medicine.

Pharaoh Seqenenre-Taa-II, the Brave, briefly ruled over Southern Egypt during the country’s occupation by the Hyksos, a foreign dynasty that held power across the kingdom for about a century (c. 1650-1550 BCE). In his attempt to oust the Hyskos, Seqenenre-Taa-II was killed. Scholars have debated the exact nature of the pharaoh’s death since his mummy was first discovered and studied in the 1880s.

These and subsequent examinations — including an X-ray study in the 1960s — noted the dead king had suffered several severe head injuries but no other wounds to his body. The prevailing theory, based on the evidence, was that the king had been captured in battle and then executed afterward, possibly by the Hyksos king himself. Others have suggested he was murdered in his sleep by a palace conspiracy.

In addition, the poor condition of the mummy suggested the embalming had been done hastily, away from the royal mummification workshop.

But computed tomography (CT) scans of the mummified remains of Seqenenre revealed new details about his head injuries, including previously undetected lesions that embalmers had skillfully concealed.

The authors of the new paper offer a novel interpretation of the events before and after the king’s death based on the computer-processed X-ray images: Seqenenre had indeed been captured on the battlefield, but his hands had been tied behind his back, preventing him from defending against the attack.

“This suggests that Seqenenre was really on the front line with his soldiers risking his life to liberate Egypt,” said lead author Dr. Sahar Saleem, a professor of radiology at Cairo University who specializes in paleoradiology. This investigative technique employs medical imaging technologies to non-invasively study a cross section of archaeological remains, including bodies. It can help determine age at death, sex and even how the person died.

For example, the CT scans, combined with other evidence, suggest the execution had been carried out by multiple attackers, which the scientists confirmed by studying five different Hyksos weapons that matched the king’s wounds.

“In a normal execution on a bound prisoner, it could be assumed that only one assailant strikes, possibly from different angles but not with different weapons,” Saleem explained. “Seqenenre’s death was rather a ceremonial execution.”

The CT study also determined that Seqenenre was about 40 when he died, based on the detailed morphology revealed in the images, providing the most precise estimate to date.

Saleem and co-author Zahi Hawass, an archaeologist and former Egyptian minister of antiquities, have pioneered the use of CT scans to study the New Kingdom pharaohs and warriors, including well-known names such as Hatshepsut, Tutankhamun, Ramesses III, Thutmose III and Rameses II. Yet Seqenenre, based on the available evidence, appears to be the only one among this illustrious group to have been on the frontline of the battlefield.

In addition, the CT study revealed important details about the mummification of Seqenenre’s body. For instance, the embalmers used a sophisticated method to hide the king’s head wounds under a layer of embalming material that functioned similarly to the fillers used in modern plastic surgery. This would imply that mummification took place in a real mummification laboratory rather than in a poorly equipped place, as previously interpreted.

Saleem said the CT scan study provides important new details about a pivotal point in Egypt’s long history. “Seqenenre’s death motivated his successors to continue the fight to unify Egypt and start the New Kingdom,” she said.

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Dr Sahar Saleem placing the mummy in the CT scanner. Sahar Saleem

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X ray of pharaoh Seqenenre-Taa-II’s torso. Sahar Saleem

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3D Virtual Reality image of the pharaoh’s skull. Sahar Saleem

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Article Source: FRONTIERS news release

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OKINAWA INSTITUTE OF SCIENCE AND TECHNOLOGY (OIST) GRADUATE UNIVERSITY:

• New research has found that a group of genes that reduces the risk of developing severe COVID-19 by around 20% is inherited from Neanderthals
• These genes, located on chromosome 12, code for enzymes that play a vital role in helping cells destroy the genomes of invading viruses
• The study suggests that enzymes produced by the Neanderthal variant of these genes are more efficient which helps protect against severe COVID-19
• This genetic variant was passed to humans around 60,000 years ago via interbreeding between modern humans and Neanderthals
• The genetic variant has increased in frequency over the last millennium and is now found in around half of people living outside Africa

SARS-CoV-2, the virus that causes COVID-19, impacts people in different ways after infection. Some experience only mild or no symptoms at all while others become sick enough to require hospitalization and may develop respiratory failure and die.

Now, researchers at the Okinawa Institute of Science and Technology Graduate University (OIST) in Japan and the Max Planck Institute for Evolutionary Biology in Germany have found that a group of genes that reduces the risk of a person becoming seriously ill with COVID-19 by around 20% is inherited from Neanderthals.

“Of course, other factors such as advanced age or underlying conditions such as diabetes have a significant impact on how ill an infected individual may become,” said Professor Svante Pääbo, who leads the Human Evolutionary Genomics Unit at OIST. “But genetic factors also play an important role and some of these have been contributed to present-day people by Neanderthals.”

Last year, Professor Svante Pääbo and his colleague Professor Hugo Zeberg reported in Nature that the greatest genetic risk factor so far identified, doubling the risk to develop severe COVID-19 when infected by the virus, had been inherited from Neanderthals.

Their latest research builds on a new study, published in December last year from the Genetics of Mortality in Critical Care (GenOMICC) consortium in the UK, which collected genome sequences of 2,244 people who developed severe COVID-19. This UK study pinpointed additional genetic regions on four chromosomes that impact how individuals respond to the virus.

Now, in a study published today in PNAS, Professor Pääbo and Professor Zeberg show that one of the newly identified regions carries a variant that is almost identical to those found in three Neanderthals – a ~50,000-year-old Neanderthal from Croatia, and two Neanderthals, one around 70,000 years old and the other around 120,000 years old, from Southern Siberia.

Surprisingly, this second genetic factor influences COVID-19 outcomes in the opposite direction to the first genetic factor, providing protection rather than increasing the risk to develop severe COVID-19. The variant is located on chromosome 12 and reduces the risk that an individual will require intensive care after infection by about 22%.

“It’s quite amazing that despite Neanderthals becoming extinct around 40,000 years ago, their immune system still influences us in both positive and negative ways today,” said Professor Pääbo.

To try to understand how this variant affects COVID-19 outcomes, the research team took a closer look at the genes located in this region. They found that three genes in this region, called OAS, code for enzymes that are produced upon viral infection and in turn activate other enzymes that degrade viral genomes in infected cells.

“It seems that the enzymes encoded by the Neanderthal variant are more efficient, reducing the chance of severe consequences to SARS-CoV-2 infections,” Professor Pääbo explained.

The researchers also studied how the newly discovered Neanderthal-like genetic variants changed in frequency after ending up in modern humans some 60,000 years ago.

To do this, they used genomic information retrieved by different research groups from thousands of human skeletons of varying ages.

They found that the variant increased in frequency after the last Ice Age and then increased in frequency again during the past millennium. As a result, today it occurs in about half of people living outside Africa and in around 30% of people in Japan. In contrast, the researchers previously found that the major risk variant inherited from Neanderthals is almost absent in Japan.

“The rise in the frequency of this protective Neanderthal variant suggests that it may have been beneficial also in the past, maybe during other disease outbreaks caused by RNA viruses,” said Professor Pääbo.

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New research has found that a group of genes that reduces the risk of developing severe COVID-19 by around 20% is inherited from Neanderthals. Bjorn Oberg, Karolinska Institutet.

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Article Source: OKINAWA INSTITUTE OF SCIENCE AND TECHNOLOGY (OIST) GRADUATE UNIVERSITY news release

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MAX PLANCK INSTITUTE FOR CHEMICAL ECOLOGY—A new study published in Nature Communications suggests that the extinction of North America’s largest mammals was not driven by overhunting by rapidly expanding human populations following their entrance into the Americas. Instead, the findings, based on a new statistical modeling approach, suggest that populations of large mammals fluctuated in response to climate change, with drastic decreases of temperatures around 13,000 years ago initiating the decline and extinction of these massive creatures. Still, humans may have been involved in more complex and indirect ways than simple models of overhunting suggest.

Before around 10,000 years ago, North America was home to many large and exotic creatures, such as mammoths, gigantic ground-dwelling sloths, larger-than-life beavers, and huge armadillo-like creatures known as glyptodons. But by around 10,000 years ago, most of North America’s animals weighing over 44 kg, also known as megafauna, had disappeared. Researchers from the Max Planck Extreme Events Research Group in Jena, Germany, wanted to find out what led to these extinctions. The topic has been intensely debated for decades, with most researchers arguing that human overhunting, climate change, or some combination of the two was responsible. With a new statistical approach, the researchers found strong evidence that climate change was the main driver of extinction.

Overhunting vs. climate change

Since the 1960’s, it has been hypothesized that, as human populations grew and expanded across the continents, the arrival of specialized “big-game” hunters in the Americas some 14,000 year ago rapidly drove many giant mammals to extinction. The large animals did not possess the appropriate anti-predator behaviors to deal with a novel, highly social, tool-wielding predator, which made them particularly easy to hunt. According to proponents of this “overkill hypothesis”, humans took full advantage of the easy-to-hunt prey, devastating the animal populations and carelessly driving the giant creatures to extinction.

Not everyone agrees with this idea, however. Many scientists have argued that there is too little archaeological evidence to support the idea that megafauna hunting was persistent or widespread enough to cause extinctions. Instead, significant climatic and ecological changes may have been to blame.

Around the time of the extinctions (between 15,000 and 12,000 years ago), there were two major climatic changes. The first was a period of abrupt warming that began around 14,700 years ago, and the second was a cold snap around 12,900 years ago during which the Northern Hemisphere returned to near-glacial conditions. One or both of these important temperature swings, and their ecological ramifications, have been implicated in the megafauna extinctions.

“A common approach has been to try to determine the timing of megafauna extinctions and to see how they align with human arrival in the Americas or some climatic event,” says Mathew Stewart, co-lead author of the study. “However, extinction is a process–meaning that it unfolds over some span of time–and so to understand what caused the demise of North America’s megafauna, it’s crucial that we understand how their populations fluctuated in the lead up to extinction. Without those long-term patterns, all we can see are rough coincidences.”

‘Dates as data’

To test these conflicting hypotheses, the authors used a new statistical approach developed by W. Christopher Carleton, the study’s other co-lead author, and published last year in the Journal of Quaternary Science. Estimating population sizes of prehistoric hunter-gatherer groups and long-extinct animals cannot be done by counting heads or hooves. Instead, archaeologists and palaeontologists use the radiocarbon record as a proxy for past population sizes. The rationale being that the more animals and humans present in a landscape, the more datable carbon is left behind after they are gone, which is then reflected in the archaeological and fossil records. Unlike established approaches, the new method better accounts for uncertainty in fossil dates.

The major problem with the previous approach is that it blends the uncertainty associated with radiocarbon dates with the process scientists are trying to identify.

“As a result, you can end up seeing trends in the data that don’t really exist, making this method rather unsuitable for capturing changes in past population levels. Using simulation studies where we know what the real patterns in the data are, we have been able to show that the new method does not have the same problems. As a result, our method is able to do a much better job capturing through-time changes in population levels using the radiocarbon record,” explains Carleton.

North American megafauna extinctions

The authors applied this new approach to the question of the Late Quaternary North American megafauna extinctions. In contrast to previous studies, the new findings show that megafauna populations fluctuated in response to climate change.

“Megafauna populations appear to have been increasing as North American began to warm around 14,700 years ago,” states Stewart. “But we then see a shift in this trend around 12,900 years ago as North America began to drastically cool, and shortly after this we begin to see the extinctions of megafauna occur.”

And while these findings suggest that the return to near glacial conditions around 12,900 years ago was the proximate cause for the extinctions, the story is likely to be more complicated than this.

“We must consider the ecological changes associated with these climate changes at both a continental and regional scale if we want to have a proper understanding of what drove these extinctions,” explains group leader Huw Groucutt, senior author of the study. “Humans also aren’t completely off the hook, as it remains possible that they played a more nuanced role in the megafauna extinctions than simple overkill models suggest.”

Many researchers have argued that it is an impossible coincidence that megafauna extinctions around the world often happened around the time of human arrival. However, it is important to scientifically demonstrate that there was a relationship, and even if there was, the causes may have been much more indirect (such as through habitat modification) than a killing frenzy as humans arrived in a region.

The authors end their article with a call to arms, urging researchers to develop bigger, more reliable records and robust methods for interpreting them. Only then will we develop a comprehensive understanding of the Late Quaternary megafauna extinction event.

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The study’s findings suggest that decreasing hemispheric temperatures and associated ecological changes were the primary drivers of the Late Quaternary megafauna extinctions in North America. Hans Sell

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A simplified radiocarbon-dated event (REC) model showing that decreases in megafauna numbers coincided with the return to near-glacial conditions at the start of the Younger-Dryas. Hans Sell & Christopher W. Carlton

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Article Source: MAX PLANCK INSTITUTE FOR CHEMICAL ECOLOGY news release

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MAX PLANCK INSTITUTE FOR THE SCIENCE OF HUMAN HISTORY—Long held in a private collection, the newly analyzed tooth of an approximately 9-year-old Neanderthal child marks the hominin’s southernmost known range. Analysis of the associated archaeological assemblage suggests Neanderthals used Nubian Levallois technology, previously thought to be restricted to Homo sapiens.

With a high concentration of cave sites harboring evidence of past populations and their behavior, the Levant is a major center for human origins research. For over a century, archaeological excavations in the Levant have produced human fossils and stone tool assemblages that reveal landscapes inhabited by both Neanderthals and Homo sapiens, making this region a potential mixing ground between populations. Distinguishing these populations by stone tool assemblages alone is difficult, but one technology, the distinct Nubian Levallois method, is argued to have been produced only by Homo sapiens.

In a new study published in Scientific Reports, researchers from the Max Planck Institute for the Science of Human History teamed up with international partners to re-examine the fossil and archaeological record of Shukbah Cave (located near the town of Shuqba in the western Judaean Mountains in the West Bank). Their findings extend the southernmost known range of Neanderthals and suggest that our now-extinct relatives made use of a technology previously argued to be a trademark of modern humans. This study marks the first time the lone human tooth from the site has been studied in detail, in combination with a major comparative study examining the stone tool assemblage.

“Sites where hominin fossils are directly associated with stone tool assemblages remain a rarity – but the study of both fossils and tools is critical for understanding hominin occupations of Shukbah Cave and the larger region,” says lead author Dr Jimbob Blinkhorn, formerly of Royal Holloway, University of London and now with the Pan-African Evolution Research Group (Max Planck Institute for the Science of Human History).

Shukbah Cave was first excavated in the spring of 1928 by Dorothy Garrod, who reported a rich assemblage of animal bones and Mousterian-style stone tools cemented in breccia deposits, often concentrated in well-marked hearths. She also identified a large, unique human molar. However, the specimen was kept in a private collection for most of the 20th century, prohibiting comparative studies using modern methods. The recent re-identification of the tooth at the Natural History Museum in London has led to new detailed work on the Shukbah collections.

“Professor Garrod immediately saw how distinctive this tooth was. We’ve examined the size, shape and both the external and internal 3D structure of the tooth, and compared that to Holocene and Pleistocene Homo sapiens and Neanderthal specimens. This has enabled us to clearly characterize the tooth as belonging to an approximately 9 year old Neanderthal child,” says Dr. Clément Zanolli, from Université de Bordeaux. “Shukbah marks the southernmost extent of the Neanderthal range known to date,” adds Zanolli.

Although Homo sapiens and Neanderthals shared the use of a wide suite of stone tool technologies, Nubian Levallois technology has recently been argued to have been exclusively used by Homo sapiens. The argument has been made particularly in southwest Asia, where Nubian Levallois tools have been used to track human dispersals in the absence of fossils.

“Illustrations of the stone tool collections from Shukbah hinted at the presence of Nubian Levallois technology so we revisited the collections to investigate further. In the end, we identified many more artifacts produced using the Nubian Levallois methods than we had anticipated,” says Blinkhorn. “This is the first time they’ve been found in direct association with Neanderthal fossils, which suggests we can’t make a simple link between this technology and Homo sapiens.”

“Southwest Asia is a dynamic region in terms of hominin demography, behavior and environmental change, and may be particularly important to examine interactions between Neanderthals and Homo sapiens,” adds Prof Simon Blockley, of Royal Holloway, University of London. “This study highlights the geographic range of Neanderthal populations and their behavioral flexibility, but also issues a timely note of caution that there are no straightforward links between particular hominins and specific stone tool technologies.”

“Up to now we have no direct evidence of a Neanderthal presence in Africa,” said Prof Chris Stringer of the Natural History Museum. “But the southerly location of Shukbah, only about 400 km from Cairo, should remind us that they may have even dispersed into Africa at times.”

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The view from Shukbah Cave. Amos Frumkin

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Photos of Nubian Levallois cores associated with Neanderthal fossils. Copyright: UCL, Institute of Archaeology & courtesy of the Penn Museum, University of Pennsylvania. Blinkhorn, et al., 2021 / CC BY 4.0

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Photo and 3D reconstruction of a tooth of a 9-year-old Neanderthal child. Copyright: Trustees of the Natural History Museum, London. Blinkhorn, et al., 2021 / CC BY 4.0

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

Partnerships

Researchers involved in this study include scholars from the Max Planck Institute for the Science of Human History, Royal Holloway, University of London, the Université de Bordeaux, the Max Planck Institute for Chemical Ecology, the University of Malta, and the Natural History Museum, London. This work was supported by the Leverhulme trust (RPH-2017-087).

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AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE—Building modern human brain organoids with the Neanderthal variant of a gene has provided a glimpse into the way substitutions in this gene impacted our species’ evolution. The ability to grow brain organoids with specific archaic genes provides a way to identify and evaluate the functional differences between the closely related genomes of hominin lineages and explore the evolutionary changes that underly the unique traits that set us as modern humans apart from our extinct relatives. While the genomes of modern humans and their archaic Neanderthal and Denisovan relatives are, in many respects, similar, the genetic differences between them are of particular interest, as they could inform on important traits for recent human evolution. For example, each contains NOVA1, an evolutionarily conserved gene known to play key roles in neurodevelopment and function. However, there are protein-coding differences between modern and archaic human variants. To evaluate the functional importance of NOVA1 variants, Cleber Trujillo and colleagues isolated the archaic NOVA1 gene from the Neanderthal genome and used CRISPR-Cas9 technology to introduce the variant into human pluripotent stem cells. This allowed Trujillo et al. to generate modern human cortical organoids expressing the archaic variant. According to the results, the addition induced slower development and higher surface complexity in cortical organoids, as well as differences in the brain’s electrophysical properties. The authors suggest that this genetic divergence may have had functional consequences for the evolutionary development of modern humans.

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A facial reconstruction from the Le Moustier Neanderthal skull in the Neues Museum, Berlin. Gary Todd, Wikimedia Commons Public Domain

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Article Source: AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE news release

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MAX PLANCK INSTITUTE FOR THE SCIENCE OF HUMAN HISTORY—Experts from the Natural History Museum, The Francis Crick Institute and the Max Planck Institute for the Science of Human History Jena have joined together to untangle the different meanings of ancestry in the evolution of our species Homo sapiens.

Most of us are fascinated by our ancestry, and by extension the ancestry of the human species. We regularly see headlines like ‘New human ancestor discovered’ or ‘New fossil changes everything we thought about our ancestry’, and yet the meanings of words like ancestor and ancestry are rarely discussed in detail. In the new paper, published in Nature, experts review our current understanding of how modern human ancestry around the globe can be traced into the distant past, and which ancestors it passes through during our journey back in time.

Co-author researcher at the Natural History Museum Prof Chris Stringer said: “Some of our ancestors will have lived in groups or populations that can be identified in the fossil record, whereas very little will be known about others. Over the next decade, growing recognition of our complex origins should expand the geographic focus of paleoanthropological fieldwork to regions previously considered peripheral to our evolution, such as Central and West Africa, the Indian subcontinent and Southeast Asia.”

The study identified three key phases in our ancestry that are surrounded by major questions, and which will be frontiers in coming research. From the worldwide expansion of modern humans about 40-60 thousand years ago and the last known contacts with archaic groups such as the Neanderthals and Denisovans, to an African origin of modern human diversity about 60-300,000 years ago, and finally the complex separation of modern human ancestors from archaic human groups about 300,000 to 1 million years ago.

The scientists argue that no specific point in time can currently be identified when modern human ancestry was confined to a limited birthplace, and that the known patterns of the first appearance of anatomical or behavioral traits that are often used to define Homo sapiens fit a range of evolutionary histories.

Co-author Pontus Skoglund from The Francis Crick Institute said: “Contrary to what many believe, neither the genetic or fossil record have so far revealed a defined time and place for the origin of our species. Such a point in time, when the majority of our ancestry was found in a small geographic region and the traits we associate with our species appeared, may not have existed. For now, it would be useful to move away from the idea of a single time and place of origin.”

“Following from this, major emerging questions concern which mechanisms drove and sustained this human patchwork, with all its diverse ancestral threads, over time and space,” said co-author Eleanor Scerri from the Pan-African Evolution Research Group at the Max Planck Institute for the Science of Human History. “Understanding the relationship between fractured habitats and shifting human niches will undoubtedly play a key role in unravelling these questions, clarifying which demographic patterns provide a best fit with the genetic and palaeoanthropological record.”

The success of direct genetic analyses so far highlights the importance of a wider, ancient genetic record. This will require continued technological improvements in ancient DNA (aDNA) retrieval, biomolecular screening of fragmentary fossils to find unrecognized human material, wider searches for sedimentary aDNA, and improvements in the evolutionary information provided by ancient proteins. Interdisciplinary analysis of the growing genetic, fossil and archaeological records will undoubtedly reveal many new surprises about the roots of modern human ancestry.

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This cranium from Jebel Irhoud in Morocco is often called a modern human ancestor. The meaning of that ancestry is discussed and disentangled in a new study by Bergstrom and colleagues. Chris Stringer

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

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About the Natural History Museum

The Natural History Museum is both a world-leading science research centre and the most-visited natural history museum in Europe. With a vision of a future in which both people and the planet thrive, it is uniquely positioned to be a powerful champion for balancing humanity’s needs with those of the natural world.

It is custodian of one of the world’s most important scientific collections comprising over 80 million specimens. The scale of this collection enables researchers from all over the world to document how species have and continue to respond to environmental changes – which is vital in helping predict what might happen in the future and informing future policies and plans to help the planet.

The Museum’s 300 scientists continue to represent one of the largest groups in the world studying and enabling research into every aspect of the natural world. Their science is contributing critical data to help the global fight to save the future of the planet from the major threats of climate change and biodiversity loss through to finding solutions such as the sustainable extraction of natural resources.

The Museum uses its enormous global reach and influence to meet its mission to create advocates for the planet – to inform, inspire and empower everyone to make a difference for nature. We welcome over five million visitors each year; our digital output reaches hundreds of thousands of people in over 200 countries each month and our touring exhibitions have been seen by around 30 million people in the last 10 years.

About the Francis Crick Institute

The Francis Crick Institute is a biomedical discovery institute dedicated to understanding the fundamental biology underlying health and disease. Its work is helping to understand why disease develops and to translate discoveries into new ways to prevent, diagnose and treat illnesses such as cancer, heart disease, stroke, infections, and neurodegenerative diseases.

An independent organisation, its founding partners are the Medical Research Council (MRC), Cancer Research UK, Wellcome, UCL (University College London), Imperial College London and King’s College London.

The Crick was formed in 2015, and in 2016 it moved into a brand new state-of-the-art building in central London which brings together 1500 scientists and support staff working collaboratively across disciplines, making it the biggest biomedical research facility under a single roof in Europe.
http://crick.ac.uk/

About the Pan-African Evolution Research Group

The Pan-African Evolution Research Group, Max Planck Institute for the Science of Human History is an independent research group dedicated to investigating the origins of our species and the parallel transformation of environments and ecosystems. The group’s work is unravelling the human story from the perspective of poorly researched regions and environments, coalescing new data and developing novel methods to understand patterns of population movement, cultural change, ecological adaptations, disease, and interactions with now extinct hominins. This research feeds into solutions of current global challenges by contributing lessons from the past to find sustainable solutions to the dual biodiversity and climate crises.

The Pan African Research Group was formed in early 2019 within the framework of the Max Planck Society’s flagship Lise Meitner Excellence Programme.

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CNRS—Almost 80 years after its discovery, a large shell from the ornate Marsoulas Cave in the Pyrenees has been studied by a multidisciplinary team from the CNRS, the Muséum de Toulouse, the Université Toulouse – Jean Jaurès and the Musée du quai Branly – Jacques-Chirac (1): it is believed to be the oldest wind instrument of its type. Scientists reveal how it sounds in a study published in the journal Science Advances on 10th February 2021.

The Marsoulas Cave, between Haute-Garonne and Ariège, was the first decorated cave to be found in the Pyrenees. Discovered in 1897, the cave bears witness to the beginning of the Magdalenian (2) culture in this region, at the end of the Last Glacial Maximum. During an inventory of the material from the archaeological excavations, most of which is kept in the Muséum de Toulouse, scientists examined a large Charonia lampas (sea snail) shell, which had been largely overlooked when discovered in 1931.

The tip of the shell is broken, forming a 3.5 cm diameter opening. As this is the hardest part of the shell, the break is clearly not accidental. At the opposite end, the shell opening shows traces of retouching (cutting) and a tomography scan has revealed that one of the first coils is perforated. Finally, the shell has been decorated with a red pigment (hematite), characteristic of the Marsoulas Cave, which indicates its status as a symbolic object.

To confirm the hypothesis that this conch was used to produce sounds, scientists enlisted the help of a horn player, who managed to produce three sounds close to the notes C, C-sharp and D. As the opening was irregular and covered with an organic coating (3), the researchers assume that a mouthpiece was also attached, as is the case for more recent conches in collection of the Musée du quai Branly – Jacques Chirac. 3D impressions of the conch will enable this lead to be explored and verify whether it can be used to produce other notes.

The first carbon-14 dating of the cave, carried out on a piece of charcoal and a fragment of bear bone from the same archaeological level as the shell, provided a date of around 18,000 years. This makes the Marsoulas conch the oldest wind instrument of its type: to date, only flutes have been discovered in earlier European Upper Palaeolithic contexts; the conches found outside Europe are much more recent.

In addition to immersing us in the sounds produced by our Magdalenian ancestors, this shell reinforces the idea of exchanges between the Pyrenees and the Atlantic coast, more than 200 kilometers away.

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At 31 cm in height, 18 cm in diameter (at the widest point) and up to 0.8 cm thick, this conch, which bears witness to a colder sea, is thus larger and thicker than more recent ones. © Carole Fritz et al. 2021.

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Reconstruction of the instrument being played. In the background, a red dotted buffalo decorates the walls of the Marsoulas Cave; similar motifs decorate the instrument. © Carole Fritz et al. 2021 / drawing: Gilles Tosello

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– Listen to the sound of the Marsoulas conch: https://soundcloud.com/cnrs_officiel/marsoulas-shell-conch-sound/s-234KE5bFZO1

– See the 3D model: https://sketchfab.com/3d-models/triton-700k-0bddff3405144c7b8f91f902e28bcc9b

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Article Source: CNRS news release

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UNIVERSITY COLLEGE LONDON—Genes that determine the shape of a person’s facial profile have been discovered by a UCL-led research team.

The researchers identified 32 gene regions that influenced facial features such as nose, lip, jaw, and brow shape, nine of which were entirely new discoveries while the others validated genes with prior limited evidence.

The analysis of data from more than 6,000 volunteers across Latin America was published today in Science Advances.

The international research team, led from UCL, Aix-Marseille University and The Open University, found that one of the genes appears to have been inherited from the Denisovans, an extinct group of ancient humans who lived tens of thousands of years ago.

The team found that the gene, TBX15, which contributes to lip shape, was linked with genetic data found in the Denisovan people, providing a clue to the gene’s origin. The Denisovans lived in central Asia, and other studies suggest they interbred with modern humans, as some of their DNA lives on in Pacific Islanders and Indigenous people of the Americas.

Co-corresponding author Dr Kaustubh Adhikari (UCL Genetics, Evolution & Environment and The Open University) said: “The face shape genes we found may have been the product of evolution as ancient humans evolved to adapt to their environments. Possibly, the version of the gene determining lip shape that was present in the Denisovans could have helped in body fat distribution to make them better suited to the cold climates of Central Asia, and was passed on to modern humans when the two groups met and interbred.”

Co-first author Dr Pierre Faux (Aix-Marseille University) said: “To our knowledge this is the first time that a version of a gene inherited from ancient humans is associated with a facial feature in modern humans. In this case, it was only possible because we moved beyond Eurocentric research; modern-day Europeans do not carry any DNA from the Denisovans, but Native Americans do.”

Co-first author Betty Bonfante (Aix-Marseille University) added: “It is one of only a few studies looking for genes affecting the face in a non-European population, and the first one to focus on the profile only.”

Researchers have only been able to analyse complex genetic data from thousands of people at once over the last two decades, since the mapping of the human genome enabled the use of genome-wide association studies to find correlations between traits and genes. This study compared genetic information from the study participants with characteristics of their face shape, quantified with 59 measurements (distances, angles and ratios between set points) from photos of the participants’ faces in profile.

Co-corresponding author Professor Andres Ruiz-Linares (Fudan University, UCL Genetics, Evolution & Environment, and Aix-Marseille University) said: “Research like this can provide basic biomedical insights and help us understand how humans evolved.”

The findings of this research could help understand the developmental processes that determine facial features, which will help researchers studying genetic disorders that lead to facial abnormalities.

The results also contribute to the understanding of the evolution of facial appearance in human and other species. One of the newly discovered genes found in this study is VPS13B, which influenced nose pointiness; the researchers also found that this gene affects nose structure in mice, indicating a broadly shared genetic basis among distantly related mammal species.

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New genetic data give clues to the evolution of the human face. Pexels, Pixabay

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Article Source: UNIVERSITY COLLEGE LONDON news release

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UNIVERSITÀ DI BOLOGNA—Neanderthals’ gut microbiota already included some beneficial micro-organisms that are also found in our own intestine. An international research group led by the University of Bologna achieved this result by extracting and analyzing ancient DNA from 50,000-year-old fecal sediments sampled at the archaeological site of El Salt, near Alicante (Spain).

Published in Communication Biology, their paper puts forward the hypothesis of the existence of ancestral components of human microbiota that have been living in the human gastrointestinal tract since before the separation between the Homo Sapiens and Neanderthals that occurred more than 700,000 years ago.

“These results allow us to understand which components of the human gut microbiota are essential for our health, as they are integral elements of our biology also from an evolutionary point of view” explains Marco Candela, the professor of the Department of Pharmacy and Biotechnology of the University of Bologna, who coordinated the study. “Nowadays there is a progressive reduction of our microbiota diversity due to the context of our modern life: this research group’s findings could guide us in devising diet- and lifestyle-tailored solutions to counteract this phenomenon”.

THE ISSUES OF THE “MODERN” MICROBIOTA

The gut microbiota is the collection of trillions of symbiont micro-organisms that populate our gastrointestinal tract. It represents an essential component of our biology and carries out important functions in our bodies, such as regulating our metabolism and immune system and protecting us from pathogenic micro-organisms.

Recent studies have shown how some features of modernity – such as the consumption of processed food, drug use, life in hyper-sanitized environments – lead to a critical reduction of biodiversity in the gut microbiota. This depletion is mainly due to the loss of a set of microorganisms referred to as “old friends”.

“The process of depletion of the gut microbiota in modern western urban populations could represent a significant wake-up call,” says Simone Rampelli, who is a researcher at the University of Bologna and first author of the study. “This depletion process would become particularly alarming if it involved the loss of those microbiota components that are crucial to our physiology”.

Indeed, there are some alarming signs. For example, in the West, we are witnessing a dramatic increase in cases of chronic inflammatory diseases, such as inflammatory bowel disease, metabolic syndrome, type 2 diabetes and colorectal cancer.

HOW THE “ANCIENT” MICROBIOTA CAN HELP

How can we identify the components of the gut microbiota that are more important for our health? And how can we protect them with targeted solutions? This was the starting point behind the idea of identifying the ancestral traits of our microbiota – i.e. the core of the human gut microbiota, which has remained consistent throughout our evolutionary history. Technology nowadays allows to successfully rise to this challenge thanks to a new scientific field, paleomicrobiology, which studies ancient microorganisms from archaeological remains through DNA sequencing.

The research group analyzed ancient DNA samples collected in El Salt (Spain), a site where many Neanderthals lived. To be more precise, they analyzed the ancient DNA extracted from 50,000 years old sedimentary feces (the oldest sample of fecal material available to date). In this way, they managed to piece together the composition of the micro-organisms populating the intestine of Neanderthals. By comparing the composition of the Neanderthals’ microbiota to ours, many similarities aroused.

“Through the analysis of ancient DNA, we were able to isolate a core of microorganisms shared with modern Homo sapiens”, explains Silvia Turroni, researcher at the University of Bologna and first author of the study. “This finding allows us to state that these ancient micro-organisms populated the intestine of our species before the separation between Sapiens and Neanderthals, which occurred about 700,000 years ago”.

SAFEGUARDING THE MICROBIOTA

These ancestral components of the human gut microbiota include many well-known bacteria (among which Blautia, Dorea, Roseburia, Ruminococcus and Faecalibacterium) that are fundamental to our health. Indeed, by producing short-chain fatty acids from dietary fibre, these bacteria regulate our metabolic and immune balance. There is also the Bifidobacterium: a microorganism playing a key role in regulating our immune defenses, especially in early childhood. Finally, in the Neanderthal gut microbiota, researchers identified some of those “old friends”. This confirms the researchers’ hypotheses about the ancestral nature of these components and their recent depletion in the human gut microbiota due to our modern life context.

“In the current modernization scenario, in which there is a progressive reduction of microbiota diversity, this information could guide integrated diet- and lifestyle-tailored strategies to safeguard the micro-organisms that are fundamental to our health”, concludes Candela. “To this end, promoting lifestyles that are sustainable for our gut microbiota is of the utmost importance, as it will help maintain the configurations that are compatible with our biology”.

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The research group analysed the ancient DNA extracted from 50,000 years old sedimentary faeces (the oldest sample of faecal material available to date). The samples were collected in El Salt (Spain), a site where many Neanderthals lived. University of Bologna

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Article Source: UNIVERSITÀ DI BOLOGNA news release

THE AUTHORS OF THE STUDY

The study titled “Components of a Neanderthal gut microbiome recovered from fecal sediments from El Salt” was published in Communication Biology. The University of Bologna participated in this study thanks to Marco Candela, Simone Rampelli, Silvia Turroni and Elena Biagi from the Department of Pharmacy and Biotechnology; Annalisa Astolfi from the Interdepartmental Center for Cancer Research “Giorgio Prodi”; Patrizia Brigidi from the Department of Medical and Surgical Sciences; and Stefano Benazzi from the Department of Cultural Heritage.

Moreover, this study saw the participation of researchers from the Universidad de La Laguna (Spain), from the Massachusetts Institute of Technology (USA) as well as the University of Oklahoma (USA) and Konrad Lorenz Institute for Evolution and Cognition Research (Austria).

UNIVERSITY OF COLORADO AT BOULDER—A new analysis of a horse previously believed to be from the Ice Age shows that the animal actually died just a few hundred years ago–and was raised, ridden and cared for by Native peoples. The study sheds light on the early relationships between horses and their guardians in the Americas.

The findings, published today in the journal American Antiquity, are the latest in the saga of the “Lehi horse.”

In 2018, a Utah couple was doing landscaping in their backyard near the city of Provo when they unearthed something surprising: an almost complete skeleton of a horse about the size of a Shetland pony. Scientists and the media took note. Preliminary data suggested that the horse might be more than 10,000 years old.

“It was found in the ground in these geologic deposits from the Pleistocene–the last Ice Age,” said William Taylor, lead author of the new research and a curator of archaeology at the CU Museum of Natural History at the University of Colorado Boulder.

Based on a detailed study of the horse’s bones and DNA, however, Taylor and his colleagues concluded that it wasn’t an Ice Age mammal at all. Instead, the animal was a domesticated horse that had likely belonged to Ute or Shoshone communities before Europeans had a permanent presence in the region.

But Taylor is far from disappointed. He said the animal reveals valuable information about how Indigenous groups in the West looked after their horses.

“This study demonstrates a very sophisticated relationship between Indigenous peoples and horses,” said Taylor, also an assistant professor in the Department of Anthropology. “It also tells us that there might be a lot more important clues to the human-horse story contained in the horse bones that are out there in libraries and museum collections.”

Written in bone

Taylor leads an effort funded by the U.S. National Science Foundation, called “Horses and Human Societies in the American West.” And he’s something akin to a forensic scientist–except he studies the remains of ancient animals, from horses to reindeer. He said that researchers can learn a lot by collecting the clues hidden in bones.

“The skeleton that you or I have is a chronicle of what we’ve done in our lives,” Taylor said. “If I were to keel over right now, and you looked at my skeleton, you’d see that I was right-handed or that I spend most of my hours at a computer.”

When Taylor first laid eyes on the Lehi horse in 2018, he was immediately skeptical that it was an Ice Age fossil. Ancient horses first evolved in North America and were common during the Pleistocene, he said, going extinct at about the same time as many other large mammals like mammoths. This horse, however, showed characteristic fractures in the vertebrae along its back.

“That was an eyebrow raiser,” Taylor said.

He explained that such fractures often occur when a human body bangs repeatedly into a horse’s spine during riding–they rarely show up in wild animals, and are often most pronounced in horses ridden without a frame saddle. So he and his colleagues decided to dig deeper.

DNA analyses by coauthors at the University of Toulouse in France revealed that the Lehi horse was a roughly 12-year-old female belonging to the species Equus caballus (today’s domestic horse). Radiocarbon dating showed that it had died sometime after the late 17th century. The horse also seemed to be suffering from arthritis in several of its limbs.

“The life of a domestic horse can be a hard one, and it leaves a lot of impacts on the skeleton,” Taylor said.

He added that scientists originally believed that the horse was so ancient in part because of its location deep in the sands along the edge of Utah Lake: Its caretakers appear to have dug a hole and intentionally buried the animal after it died, making it look initially as if it had come from Ice Age sediments.

And despite the animal’s injuries, which would have probably made the Lehi horse lame, people had continued to care for the mare–possibly because they were breeding her with stallions in their herd.

Hidden history

For Carlton Shield Chief Gover, a coauthor of the new study, the research is another example of the buried history of Indigenous groups and horses.

He explained that most researchers have tended to view this relationship through a European lens: Spaniards brought the animals to the Americas on boats, and white settlers shaped how Native peoples interacted with them.

But that view glosses over just how uniquely Indigenous the horse became in the Americas after those first introductions.

“There was a lot going on that Europeans didn’t see,” said Shield Chief Gover, a graduate student at CU Boulder and a tribal citizen of the Pawnee Nation. “There was a 200-year period where populations in the Great Plains and the West were adapting their cultures to the horse.”

For many Plains groups, horses quickly changed nearly every aspect of life.

“There was more raiding and fewer battles,” Shield Chief Gover said. “Horses became deeply integrated into Plains cultures, and changed the way people moved, traded, hunted and more.”

He and Taylor hope that their research will, alongside Indigenous oral traditions, help to shed light on those stories. Taylor, for his part, suspects that the Lehi horse may not be the only set of remains mistakenly shelved with Ice Age animals in museum collections around the country.

“I think there are a lot more out there like this,” he said.

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Study coauthor Isaac Hart of the university of Utah compares a healthy talus bone from the Lehi horse with one heavily impacted by arthritis. William Taylor

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Article Source: UNIVERSITY OF COLORADO AT BOULDER news release

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THE HEBREW UNIVERSITY OF JERUSALEM—While scientists and historians have long surmised that etchings on stones and bones have been used as a form of symbolism dating back as early as the Middle Paleolithic period (250,000-45,000 BCE), findings to support that theory are extremely rare.

A recent discovery by archeologists from the Hebrew University and the University of Haifa alongside a team from the Le Centre National de la Recherche Scientifique in France have uncovered evidence of what may be the earliest-known use of symbols. The symbols were found on a bone fragment in the Ramle region in central Israel and are believed to be approximately 120,000 years old.

Remarkably the fragment remained largely intact and the researchers were able to detect six similar etchings on one side of the bone, leading them to believe that they were in the possession of something which held symbolic or spiritual significance. The find which was recently published in the scientific journal ‘Quaternary International’ was discovered in a trove of flint tools and animal bones exposed at a site during archaeological excavations.

Dr. Yossi Zaidner of the Institute of Archeology at Hebrew University says that the site was likely used as a camp or a meeting place for Paleolithic hunters who would then slaughter the animals they caught at that location. The identified bone is believed to have come from an extinct large wild cattle, a species which was very common in the Middle East at that time.

Using three-dimensional imaging, microscopic methods of analysis and experimental reproduction of engravings in the laboratory, the team was able to identify six different engravings ranging from 38 to 42 millimeters in length. Dr. Iris Groman-Yaroslavski from the University of Haifa explained, “Based on our laboratory analysis and discovery of microscopic elements, we were able to surmise that people in prehistoric times used a sharp tool fashioned from flint rock to make the engravings.”

The paper’s authors stress that their analysis makes it very clear that the engravings were definitely intentionally man made and could not have been the result of animal butchering activities or natural processes over the millennia. They pointed to the fact that the grooves of the engravings discovered are in a clear U-shape and wide and deep enough that they could not have been made by anything other than humans intent on carving lines into the bone.

The analysis was also able to determine that the work was performed by a right-handed craftsman in a single working session.

Ms. Marion Prévost from the Institute of Archeology at Hebrew University says that every indication was that there was a definite message behind what was carved into the bone. “We reject any assumption that these grooves were some sort of inadvertent doodling. That type of artwork wouldn’t have seen this level of attention to detail.”

So then what was the message behind the six lines in the bone? The authors write, “This engraving is very likely an example of symbolic activity and is the oldest known example of this form of messaging that was used in the Levant. We hypothesize that the choice of this particular bone was related to the status of that animal in that hunting community and is indicative of the spiritual connection that the hunters had with the animals they killed.”

Dr. Zaidner said, “It is fair to say that we have discovered one of the oldest symbolic engraving ever found on earth- and certainly the oldest in the Levant. This discovery has very important implications for understanding of how symbolic expression developed in humans. At the same time, while it is still not possible to determine the exact meaning of these symbols we hope that continued research will unveil those key details.”

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Illustration and photograph of the bone and the engravings. Marion Prévost

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Above and below: The find within its archaeological context at the site. Courtesy HUJI

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Article Source: THE HEBREW UNIVERSITY OF JERUSALEM news release

PLOS—New analysis of a 20th Dynasty mummified individual reveals her rare mud carapace, according to a study* published February 3, 2021 in the open-access journal PLOS ONE by Karin Sowada from Macquarie University, Sydney, Australia, and colleagues.

Studies of mummified bodies from the late New Kingdom to the 21st Dynasty (c. 1294-945 BC) have occasionally reported a hard resinous shell protecting the body within its wrappings, especially for royal mummies of the period. Here, Sowada and colleagues describe their discovery of a rare painted mud carapace enclosing an adult mummy in Sydney’s Chau Chak Wing Museum.

Sir Charles Nicholson bought the mummified body, lidded coffin, and mummy board as a set during a trip to Egypt in 1856-7, donating it to the University of Sydney in 1860. The coffin inscription identifies the owner as a titled woman named Meruah, and the iconography dates it to approximately 1000 BC. Though the mummified individual underwent a full computed tomography (CT) scan in 1999, the authors rescanned the body for the current study using updated technology.

Using this new visualization of the dentition and skeleton, the authors determined the mummified individual was a young middle adult (26-35 years). Though the body scans did not reveal external genitalia, and internal reproductive organs had been removed during the mummification process, osseous secondary sexual characteristics (hip bones, jaw, and cranium) strongly suggest the mummified individual was female. The current analysis of the mummification technique and radiocarbon dating of textile samples from the linen wrappings place the mummified individual in the late New Kingdom (c. 1200-1113 BC). This means the body is older than the coffin, suggesting local 19th century dealers placed an unrelated body in the coffin to sell as a complete set. The new scans also revealed the extent and nature of the mud carapace, showing the mud shell fully sheaths the body and is layered within the linen wrappings. Images of the inmost layers indicate the body was damaged relatively shortly after initial mummification, and the mud carapace and additional wrappings applied to reunify and restore the body. In addition to its practical restorative purpose, the authors suggest the mud carapace gave those who cared for the deceased the chance to emulate elite funerary practices of coating the body in an expensive imported resin shell with cheaper, locally available materials.

Though this mud carapace treatment has not been previously documented in the literature, the authors note it’s not yet possible to determine how frequent this treatment may have been for non-elite mummies in the late New Kingdom of ancient Egypt—and suggest further radiological studies on other non-royal mummies may reveal more about this practice.

The authors add: “The mud shell encasing the body of a mummified woman within the textile wrappings is a new addition to our understanding of ancient Egyptian mummification.”

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Mummified individual and coffin in the Nicholson Collection of the Chau Chak Wing Museum, University of Sydney. A. Mummified individual, encased in a modern sleeve for conservation, NMR.27.3. B. Coffin lid, NMR.27.1. (Published under a CC BY license, with permission from the Chau Chak Wing Museum, original copyright 2019). Sowada et al, PLOS ONE (CC BY 4.0 https://creativecommons.org/licenses/by/4.0/)

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Article Source: PLOS news release

*Sowada K, Power RK, Jacobsen G, Murphy T, McClymont A, Bertuch F, et al. (2021) Multidisciplinary discovery of ancient restoration using a rare mud carapace on a mummified individual from late New Kingdom Egypt. PLoS ONE 16(2): e0245247.  https://doi.org/10.1371/journal.pone.0245247

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GFZ GEOFORSCHUNGSZENTRUM POTSDAM, HELMHOLTZ CENTRE—Large parts of today’s Sahara Desert were green thousands of years ago. Prehistoric engravings of giraffes and crocodiles testify to this, as does a stone-age cave painting in the desert that even shows swimming humans. However, these illustrations only provide a rough picture of the living conditions. Recently, more detailed insights have been gained from sediment cores extracted from the Mediterranean Sea off the coast of Libya. An international research team examined these cores and discovered that the layers of the seafloor tell the story of major environmental changes in North Africa over the past 160,000 years. Cécile Blanchet of the German Research Centre for Geosciences GFZ and her colleagues from Germany, South Korea, the Netherlands and the USA report on this in the journal Nature Geoscience.

Together with the GEOMAR Helmholtz Centre for Ocean Research Kiel, a team of scientists organized a research cruise on the Dutch vessel Pelagia to the Gulf of Sirte in December 2011. “We suspected that when the Sahara Desert was green, the rivers that are presently dry would have been active and would have brought particles into the Gulf of Sirte”, says lead author Cécile Blanchet. Such sediments would help to better understand the timing and circumstances for the reactivation of these rivers.

Using a method called “piston coring”, the scientists were able to recover 10-meters long columns of marine mud. “One can imagine a giant hollow cylinder being pushed into the seafloor”, says co-author Anne Osborne from GEOMAR, who was onboard the research ship. “The marine mud layers contain rock fragments and plant remains transported from the nearby African continent. They are also full of shells of microorganisms that grew in seawater. Together, these sediment particles can tell us the story of past climatic changes”, explains Blanchet.

“By combining the sediment analyses with results from our computer simulation, we can now precisely understand the climatic processes at work to explain the drastic changes in North African environments over the past 160,000 years”, adds co-author Tobias Friedrich from the University of Hawai’i.

From previous work, it was already known that several rivers episodically flowed across the region, which today is one of the driest areas on Earth. The team’s unprecedented reconstruction continuously covers the last 160,000 years. It offers a comprehensive picture of when and why there was sufficient rainfall in the Central Sahara to reactivate these rivers. “We found that it is the slight changes in the Earth’s orbit and the waxing and waning of polar ice sheets that paced the alternation of humid phases with high precipitation and long periods of almost complete aridity”, explains Blanchet.

The fertile periods generally lasted five thousand years and humidity spread over North Africa up to the Mediterranean coast. For the people of that time, this resulted in drastic changes in living conditions, which probably led to large migratory movements in North Africa. “With our work we have added some essential jigsaw pieces to the picture of past Saharan landscape changes that help to better understand human evolution and migration history”, says Blanchet. “The combination of sediment data with computer-simulation results was crucial to understand what controlled the past succession of humid and arid phases in North Africa. This is particularly important because it is expected that this region will experience intense droughts as a consequence of human-induced climate change.”

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Engraving of Giraffes near Gobero in Niger, ca. 8,000 yrs old, witness green times in the desert. Mike Hettwer, 2006, www.hettwer.com

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Overview of the area of study in Northern Africa and off the coast of Libya. The old river courses and the place where the sediment core was taken can also be seen. Axel Timmermann

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Article Source: GFZ GEOFORSCHUNGSZENTRUM POTSDAM, HELMHOLTZ CENTRE news release

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CELL PRESS—Despite long-standing ideas about the importance of thumb evolution in tool use and development, questions remain about exactly when human-like manual dexterity and efficient thumb use arose—and which hominin species was the first to have this ability. Now, researchers who’ve analyzed the biomechanics and efficiency of the thumb across different fossil human species using virtual muscle modeling have new insight into when these abilities first arose and what they’ve meant for the development of more complex human culture. The findings, appearing January 28 in the journal Current Biology*, suggest that a fundamental aspect of human thumb opposition first appeared approximately 2 million years ago and was not found in the earliest proposed stone tool makers.

“Increased manual dexterity in the form of efficient thumb opposition was among the early defining characteristics of our lineage, providing a formidable adaptive advantage to our ancestors,” said Katerina Harvati of the Eberhard Karls University of Tübingen. “It is likely a crucial element underlying the development of complex culture over the last 2 million years, shaping our biocultural evolution.”

Earlier attempts to study thumb dexterity evolution had relied on comparisons between the skeletal anatomy of modern humans and earlier hominin species. The assumption was that similarities in skeletal remains to the human form could be taken as evidence of dexterity. In the new study, the team led by Harvati took a new and more comprehensive approach.

“Our methodology integrates cutting-edge virtual muscle modeling with three-dimensional analysis of bone shape and size,” first author and hand biomechanics expert Alexandros Karakostis, explains. “This process includes the precise 3D study of the areas of the bones where muscles attach in life. Importantly, we were able to validate the predictions of our models by confirming that the differences observed between living taxa—chimpanzees and modern humans—reflect those reported from past experimental studies.”

By applying this new approach to answer the question, the researchers showed that thumb efficiency and dexterity had increased to a significant extent in hominins that lived 2 million years ago in South Africa. At the same time, they found that the degree of this dexterity was consistently lower in the earliest proposed tool-making species, the Australopithecines. That includes the species Australopithecus sediba, which is also dated to approximately 2 million years ago. That’s notable because researchers had previously suggested that the human-like thumb proportions of A. sediba reflected tool-making capabilities.

“One of the greatest surprises was to find that hominin hand fossils from the Swartkrans site in South Africa, which date to ca. 2 million years ago and are attributed to either early Homo or to the extinct hominin side branch Paranthropus robustus, could achieve a thumb-using dexterity similar to that of modern humans,” Karakostis said.

The new findings further show that later-arising species, belonging to our own genus Homo—including Neanderthals as well as early and recent Homo sapiens—share similarly high degrees of manual dexterity. Those findings applied also to the small-brained species Homo naledi, despite the fact that this species has not yet been found in association with stone tools.

“These consistently high dexterity levels in species of Homo are indicative of the great adaptive value of thumb opposition for human biocultural evolution,” Harvati says.

The researchers note that the most important implication of their new findings is that an early increase of thumb dexterity about 2 million years ago may have been a foundation for the gradual development of complex culture. They highlight that this timeframe includes important biocultural developments such as the appearance of the large-brained Homo erectus lineage and its dispersal out of Africa. Around the same time, humans gradually began to exploit animal resources and to rely more heavily on stone tool technologies.

The researchers now plan to look even more closely at specific groups, such as Neanderthals, so as to further elucidate the details of their manual dexterity and how they may have differed from that of modern humans. They’ll also more closely investigate the habitual manual activities of early hominins to further shed light on the behaviors that marked the transition to systematic tool production and use among our distant ancestors.

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This image diagrams the difference between human and chimpanzee models of thumb muscles, which the researchers used to study the evolution of thumb dexterity. Professor Katerina Harvati, Dr. Alexandros Karakostis, and Dr. Daniel Haeufle

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This work was supported by the European Research Council, the German Research Foundation, and the Ministry of Science, Research, and the Arts Baden-Württemberg.

*Current Biology, Karakostis et al.: “Biomechanics of the human thumb and the evolution of dexterity” https://www.cell.com/current-biology/fulltext/S0960-9822(20)31893-5

Article Source: Cell Press news release

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