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New evidence: Neanderthals buried their dead

Was burial of the dead practiced by Neanderthals or is it an innovation specific to our species? There are indications in favor of the first hypothesis but some scientists remain skeptical. For the first time in Europe, however, a multi-disciplinary team led by researchers at the CNRS and the Muséum national d’histoire naturelle (France) and the University of the Basque Country (Spain)1 has demonstrated, using a variety of criteria, that a Neanderthal child was buried, probably around 41,000 years ago, at the Ferrassie site (Dordogne). Their study* is published in the journal Scientific Reports on 9th December 2020.

Dozens of buried Neanderthal skeletons have been discovered in Eurasia, leading some scientists to deduce that, like us, Neanderthals buried their dead. Other experts have been skeptical, however, given that the majority of the best-preserved skeletons, found at the beginning of the 20th century, were not excavated using modern archaeological techniques.

It is within this framework that an international team1 led by paleoanthropologists Antoine Balzeau (CNRS and Muséum national d’histoire naturelle, France) and Asier Gómez-Olivencia (University of the Basque Country, Spain), analyzed a human skeleton from one of the most famous Neanderthal sites in France: the La Ferrassie rock shelter, Dordogne. After six Neanderthal skeletons were discovered at the beginning of the 20th century, the site delivered a seventh between 1970 and 1973, belonging to a child of around two years old. For almost half a century, the collections associated with this specimen remained unexploited in the archives of the Musée d’archéologie nationale.

Recently, a multidisciplinary team, assembled by the two researchers, reopened the excavation notebooks and reviewed the material, revealing 47 new human bones not identified during excavation and undoubtedly belonging to the same skeleton. The scientists also carried out a thorough analysis of the bones: state of preservation, study of proteins, genetics, dating, etc. They returned to La Ferrassie in the hope of finding further fragments of the skeleton; although no new bones were discovered, using the notebooks of their predecessors, they were able to reconstruct and interpret the spatial distribution of the human remains and the rare associated animal bones.

The researchers showed that the skeleton had been buried in a sedimentary layer which inclined to the west (the head, to the east, was higher than the pelvis), while the other stratigraphic layers of the site inclined to the north-east. The bones, which were relatively unscattered, had remained in their anatomical position. Their preservation, better than that of the bison and other herbivores found in the same stratum, indicates a rapid burial after death. Furthermore, the contents of this layer proved to be earlier than the surrounding sediment2. Finally, a tiny bone, identified as human by the proteins and as Neanderthal by its mitochondrial DNA, was directly dated using carbon-14. At around 41,000 years old, this makes it one of the most recent directly dated Neanderthal remains.   

This new information proves that the body of this two-year-old Neanderthal child was purposefully deposited in a pit dug in a sedimentary layer around 41,000 years ago; however, further discoveries will be necessary to understand the chronology and geographical extension of Neanderthal burial practices.

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Examining material from the 1970s excavations at the Musée d’archéologie nationale, France. Thousands of bone remains were sorted and 47 new fossil remains belonging to the Neanderthal child ‘La Ferrassie 8’ were identified. © Antoine Balzeau – CNRS/MNHN

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Reconstruction of the child’s burial by Neanderthals at La Ferrassie. © Emmanuel Roudier

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Article Source: CNRS news release

Notes

  1. 1. The other contributors to this study work at the Institut de recherche sur les archéomatériaux – Centre de recherche en physique appliquée à l’archéologie (CNRS/Université Bordeaux Montaigne), the Géosciences Rennes laboratory (CNRS/Université Rennes 1), De la Préhistoire à l’actuel : culture, environnement et anthropologie laboratory (CNRS/Université de Bordeaux/Ministère de la Culture), the Musée d’archéologie nationale and the Musée national de Préhistoire des Eyzies-de-Tayac in France; at the Max Planck Institute for Evolutionary Anthropology in Germany; at the University of Bologna in Italy; at the University of Copenhagen in Denmark.
  2. 2. Dated by thermoluminescence. The result indicates how long it is since the sediment last saw light and therefore the date of the burial.

*Pluridisciplinary evidence for burial for the La Ferrassie Neandertal child, Antoine Balzeau, Alain Turq, Sahra Talamo, Camille Daujeard, Guillaume Guérin, Frido Welker, Isabelle Crevecoeur, Helen Fewlass, Jean‑Jacques Hublin, Christelle Lahaye, Bruno Maureille, Matthias Meyer, Catherine Schwab & Asier Gómez‑Olivencia, Scientific Reports, 9 December 2020. DOI: 10.1038/s41598-020-77611-z.

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Palaeolithic sea voyages to Japanese islands was choice, not chance

UNIVERSITY OF TOKYO, SCIENTIFIC REPORTS—The degree of intentionality behind ancient ocean migrations, such as that to the Ryukyu Islands between Taiwan and mainland Japan, has been widely debated. Researchers used satellite-tracked buoys to simulate ancient wayward drifters and found that the vast majority failed to make the contested crossing. They concluded that Paleolithic people 35,000-30,000 years ago must therefore have made the journey not by chance but by choice.

To determine the likelihood of humans reaching the Ryukyu Islands via accidental drift with the Kuroshio Current, Yousuke Kaifu and colleagues studied the trajectories of 138 satellite-tracked buoys, which drifted past Taiwan or northeastern Luzon between 1989 and 2017. Of the 122 buoys that drifted past Taiwan 114 were carried northward by the Kuroshio and, of these, 3 came within 20 kilometers of the central and south Ryukyu Islands under adverse weather conditions. Of the 16 buoys that drifted past Luzon, 13 drifted with the Kuroshio but only one moved towards the Ryukyu Islands due to a typhoon. As the flow of the Kuroshio Current is thought to have remained unchanged during the past 100,000 years, the results indicate that humans in drifting boats were unlikely to reach the islands via accidental drift with the Kuroshio Current. The findings suggest that humans deliberately crossed one of the world’s strongest currents in order to migrate to the Ryukyu Islands approximately 35,000 years ago.

Human migration over the last 50,000 years is an essential part of human history. One aspect of this story that fascinates many is the ways in which ancient people must have crossed between separate land masses. Professor Yosuke Kaifu from the University Museum at the University of Tokyo and his team explore this subject, in particular a crossing known to have taken place 35,000-30,000 years ago from Taiwan to the Ryukyu Islands, including Okinawa, in southwestern Japan.

“There have been many studies on Paleolithic migrations to Australia and its neighboring landmasses, often discussing whether these journeys were accidental or intentional,” said Kaifu. “Our study looks specifically at the migration to the Ryukyu Islands, because it is not just historically significant, but is also very difficult to get there. The destination can be seen from the top of a coastal mountain in Taiwan, but not from the coast. In addition, it is on the opposite side of the Kuroshio, one of the strongest currents in the world. If they crossed this sea deliberately, it must have been a bold act of exploration.”

This issue of the intentionality of this journey is less straightforward to solve than you might imagine. To investigate the likelihood of the journey occurring by chance, the effect of the Kuroshio on drifting craft needed measuring. To do this, Kaifu and his team used 138 satellite-tracked buoys to trace the path of a would-be drifter caught on this journey.

“The results were clearer than I would have expected,” said Kaifu. “Only four of the buoys came within 20 kilometers of any of the Ryukyu Islands, and all of these were due to adverse weather conditions. If you were an ancient mariner, it’s very unlikely you would have set out on any kind of journey with such a storm on the horizon. What this tells us is that the Kuroshio directs drifters away from, rather than towards, the Ryukyu Islands; in other words, that region must have been actively navigated.”

You might wonder how we can be so sure the current itself is the same now as it was over 30,000 years ago. But existing evidence, including geological records, tell researchers that currents in the region have been stable for at least the last 100,000 years. As for the researchers’ confidence that Paleolithic voyagers would not dare face stormy conditions that might otherwise explain chance migrations, prior research suggests that these voyagers were groups including families, whose modern-day analogues do not take such risks.

“At the beginning, I had no idea how to demonstrate the intentionality of the sea crossings, but I was lucky enough to meet my co-authors in Taiwan, leading authorities of the Kuroshio, and came across the idea of using the tracking buoys,” said Kaifu. “Now, our results suggest the drift hypothesis for Paleolithic migration in this region is almost impossible. I believe we succeeded in making a strong argument that the ancient populations in question were not passengers of chance, but explorers.”

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A candidate bamboo craft for the Ryukyu migration built for a re-enactment of that crossing. © 2020 Yosuke Kaifu

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Tracking data for 138 buoys, including several which ventured relatively near the target islands. © 2020 Tien-Hsia Kuo

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One of the satellite-tracking buoys. © 2020 Lagrangian Drifter Laboratory/University of California, San Diego

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Article Source: UNIVERSITY OF TOKYO and SCIENTIFIC REPORTS news releases

Kaifu, Y., Kuo, T.-H., Kubota, Y., Jan, S. Palaeolithic voyage for invisible islands beyond the horizonScientific Reports. DOI: 10.1038/s41598-020-76831-7

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African trade routes sketched out by medieval beads

UNIVERSITÉ DE GENÈVE—The origin of glass beads dates back to early ancient times. The chemical composition of the beads and their morphological and technical characteristics can reveal where they come from; this information can then be used to reconstruct the trade channels between glass production areas and the sites where the beads were used at different times. Archaeologists from the University of Geneva (UNIGE), working in partnership with the Institut de Recherche sur les Archéomatériaux at the Centre Ernest-Babelon in Orléans, France, analyzed 16 archaeological glass beads found at three rural sites in Mali and Senegal from between the 7th and 13th centuries AD. In the journal Plos One, the scientists demonstrate that the glass they are made of probably came from Egypt, the Levantine coast and the Middle East. The results show that international trade linking Africa to Europe and Asia during the development of the large West African state configurations did not stop at the great urban centers located along the Niger River: it also connected with local and regional trade. In this way, an extensive network including sub-Saharan rural areas and trans-Saharan trade routes took shape.

The glass beads uncovered in Africa do not only come from the well-known junk cargoes shipped by boat to be exchanged for slaves around the 18th century. Their provenance is much older and their places of origin many and diverse. In western sub-Saharan Africa, the beads have been found in urban archaeological sites from the mediaeval period along the Niger River. Several Arabic texts describe these trade routes crossing the Sahara and connecting the African continent to Europe and Asia. «Trans-Saharan caravans traded horses, guns, luxury objects and salt for ivory, gold and slaves», explains Anne Mayor, a researcher in the Anthropology Unit in UNIGE’s Faculty of Sciences.

Members of the «Archaeology and Population in Africa Laboratory of UNIGE have been carrying out archaeological excavations for several decades at sites in central Mali and eastern Senegal, including old cemeteries and villages. They have investigated the evolution of lifestyles and techniques. A total of 16 glass beads has been unearthed at three of these sites dating from between the 7th and 13th centuries AD. To understand their provenance and form a picture of what trade was like at a time when the first African kingdoms were developing, the archaeologists embarked on an analysis of their morphological and technical characteristics together with their chemical composition.

Beads: a type of «crystal ball»

Three main components are required for the production of glass. The primary ingredient is silica, which is obtained from quartz ore or sand. This has to be melted, but since its melting point is too high, mineral or vegetable «flux» is added to help the process. Finally, lime from limestone rocks or shells serves as a stabilizer for the glass structure. «By analyzing the chemical composition of the glass, we can begin to understand the origin of the raw materials used to manufacture it and, in some cases, the period when it was produced», states the first author of the study, Miriam Truffa Giachet, for whom this work is an integral part of her UNIGE doctoral thesis.

«It’s also important to understand that the production of glass beads involves several stages, generally located in different places,» continues the Geneva-based researcher. The first step consists of collecting the raw materials, which are then transported to a primary production center where the raw glass is made. This is then transported to secondary centers to manufacture glass objects before being distributed to various sites through trade. The scientists cross-referenced the results of the chemical analysis of the beads with historical sources and data from archaeological excavations, thereby obtaining precise information about the origin of the beads.

The lab meets the field

The study’s originality lies in the cross-analysis of archaeological field data and laboratory data to further our understanding of African archaeological objects. The scientists used laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to evaluate the chemical composition of the beads without damaging them, thanks to laser sampling that tests very small quantities of material. In this way, the probable origins of the beads were identified: Egypt, the Levantine coast and the Middle East.

It follows that sub-Saharan agropastoralists (whose dwellings and tombs archaeological excavations have found traces of) were incorporated into very broad trade networks, as revealed by the presence of objects from distant sources. These locations were in a peripheral position in relation to the regional power centers, but at least one of them, in eastern Senegal, was close to gold mines – a resource that made a significant contribution to their wealth. It is interesting to note that none of the beads analyzed had the characteristics typical of the solitary African primary production center active at the time, in Nigeria, despite the fact that there was internal east-west trade.

Sub-Saharan Africa: connected to the rest of the world

The study adds weight to the idea that at this time prestigious goods circulated through trade routes linking sub-Saharan Africa to the rest of the world. «The western popular imagination thinks that Africa was disconnected beyond the Sahara, but this was clearly not the case! It was fully integrated into a large international network that linked Africa, Europe and Asia. It was connected to local trade that brought goods of distant origin to the hinterland,» concludes Dr Mayor.

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The glass beads studied, unearthed by archaeological excavations in Dourou-Boro and Sadia, Mali, and Djoutoubaya, Senegal. © UNIGE/Truffa Giachet/Spuhler

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Article Source: UNIVERSITÉ DE GENÈVE news release 

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CU Anschutz researcher offers new theory on `Venus’ figurines

UNIVERSITY OF COLORADO ANSCHUTZ MEDICAL CAMPUS, AURORA, Colo. (Dec. 1, 2020) – One of world’s earliest examples of art, the enigmatic `Venus’ figurines carved some 30,000 years ago, have intrigued and puzzled scientists for nearly two centuries. Now a researcher from the University of Colorado Anschutz Medical Campus believes he’s gathered enough evidence to solve the mystery behind these curious totems.

The hand-held depictions of obese or pregnant women, which appear in most art history books, were long seen as symbols of fertility or beauty. But according to Richard Johnson, MD, lead author of the study published today in the journal, Obesity, the key to understanding the statues lays in climate change and diet.

“Some of the earliest art in the world are these mysterious figurines of overweight women from the time of hunter gatherers in Ice Age Europe where you would not expect to see obesity at all,” said Johnson, a professor at the University of Colorado School of Medicine specializing in renal disease and hypertension. “We show that these figurines correlate to times of extreme nutritional stress.”

Early modern humans entered Europe during a warming period about 48,000 years ago. Known as Aurignacians, they hunted reindeer, horses and mammoths with bone-tipped spears. In summer they dined on berries, fish, nuts and plants. But then, as now, the climate did not remain static.

As temperatures dropped, ice sheets advanced and disaster set in. During the coldest months, temperatures plunged to 10-15 degrees Celsius. Some bands of hunter gatherers died out, others moved south, some sought refuge in forests. Big game was overhunted.

It was during these desperate times that the obese figurines appeared. They ranged between 6 and 16 centimeters in length and were made of stone, ivory, horn or occasionally clay. Some were threaded and worn as amulets.

Johnson and his co-authors, Professor (ret.) of Anthropology John Fox, PhD, of the American University of Sharjah in the United Arab Emirates, and Associate Professor of Medicine Miguel Lanaspa-Garcia, PhD, of the CU School of Medicine, measured the statues’ waist-to-hip and waist-to-shoulder ratios. They discovered that those found closest to the glaciers were the most obese compared to those located further away. They believe the figurines represented an idealized body type for these difficult living conditions.

“We propose they conveyed ideals of body size for young women, and especially those who lived in proximity to glaciers,” said Johnson, who in addition to being a physician has an undergraduate degree in anthropology. “We found that body size proportions were highest when the glaciers were advancing, whereas obesity decreased when the climate warmed and glaciers retreated.”

Obesity, according to the researchers, became a desired condition. An obese female in times of scarcity could carry a child through pregnancy better than one suffering malnutrition. So the figurines may have been imbued with a spiritual meaning – a fetish or magical charm of sorts that could protect a woman through pregnancy, birth and nursing.

Many of the figurines are well-worn, indicating that they were heirlooms passed down from mother to daughter through generations. Women entering puberty or in the early stages of pregnancy may have been given them in the hopes of imparting the desired body mass to ensure a successful birth.

“Increased fat would provide a source of energy during gestation through the weaning of the baby and as well as much needed insulation,” the authors said.

Promoting obesity, said Johnson, ensured that the band would carry on for another generation in these most precarious of climatic conditions.

“The figurines emerged as an ideological tool to help improve fertility and survival of the mother and newborns,” Johnson said. “The aesthetics of art thus had a significant function in emphasizing health and survival to accommodate increasingly austere climatic conditions.”

The team’s success in amassing evidence to support its theory came from applying measurements and medical science to archaeological data and behavioral models of anthropology.

“These kinds of interdisciplinary approaches are gaining momentum in the sciences and hold great promise,” Johnson said. “Our team has other subjects of Ice Age art and migration in its research sights as well.”

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The Venus Willendorf figurine, discovered at Willendorf in Austria, dated to about 30,000 years ago. Bjørn Christian Tørrissen, Creative Commons Attribution-Share Alike 4.0 International 

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Article Source: University of Colorado Anschutz news release

About the University of Colorado Anschutz Medical Campus

The University of Colorado Anschutz Medical Campus is a world-class medical destination at the forefront of transformative science, medicine, education, and healthcare. The campus encompasses the University of Colorado health professional schools, more than 60 centers and institutes, and two nationally ranked hospitals that treat more than 2 million adult and pediatric patients each year. Innovative, interconnected and highly collaborative, together we deliver life-changing treatments, patient care, professional training, and conduct world-renowned research powered by more than $500 million in research awards. For more information, visit https://www.cuanschutz.edu

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Pyroclasts protect the paintings of Pompeii buried but damage them when they are unearthed

UNIVERSITY OF THE BASQUE COUNTRY—The ancient city of Pompeii (in the south of Italy) ended up buried under ash and volcanic material in 79 CE as a consequence of the eruption of Mount Vesuvius. That fateful event made the unprecedented conservation of the archaeological site in the area possible because the pyroclastic materials spewed out by Vesuvius have protected the remains from external damage. So not only in cultural but also in scientific terms they are in fact highly prized sites where tourists and professionals of archaeology and even chemistry mingle.

For over 10 years the UPV/EHU’s IBeA group, attached to the department of Analytical Chemistry, has been working at Pompeii within the framework of the Analytica Pompeiana Universitatis Vasconicae-APUV project. In 2015 the UPV/EHU and the Archaeological Park of Pompeii signed the first of the agreements thanks to which the methodologies and portable devices used by the research group are allowing the paintings to be analyzed using non-destructive techniques.

Various studies conducted at the House of Marcus Lucretius, the House of Ariadne and the Casa degli Amorini Dorati or House of the Golden Cupids have concluded that “salts are responsible for the worst and most visible damage to the murals. In the end, the salts may dissolve and as a result material such as pigments, the pictorial layer, the mortar, etc. may be lost”, said Maite Maguregui, lead researcher in this study. In this respect, the researchers have concluded that the leached ions from the pyroclastic materials and the ion-rich underground waters from the volcanic rocks promote the crystallization of certain salts.

“While the paintings remain underground, they are protected by the pyroclasts; but once they are brought to the surface, the salts start to form owing to the effect of the air, humidity, etc. So in order to conserve the mural paintings it is important to know in each case what the salt load of the surrounding pyroclasts is to be able to block, reduce or prevent potential damage. In fact, in Pompeii a large proportion remains buried and waiting to be studied,” added Maguregui.

Fluorine marking the impact of the volcanic materials

“When the volcano erupted, it spewed out huge quantities of materials and the pyroclastic material is not homogeneous across the whole area; many different strata can be found,” explained the researcher. Mineralogical analyses of samples collected at various points were made in the study, and the compositions of the leachates were determined. Thermodynamic modeling was also carried out to predict which salts can precipitate as a result of leaching and to determine their origins. It was concluded that the salts provided by the modeling coincide with those detected in the paintings.

The salts analyzed in the murals contain fluorine ions, among other things. “Fluorines are ions of volcanic origin; it is not one of the main elements in the atmosphere. The emergence of fluorine salts indicates that the volcanic materials and the subterranean waters are exerting an influence on the crystallization of these salts,” she explained. “So with the fluorine found in the mural it is possible to trace the impact that has been exerted and continues to be exerted by the pyroclasts and the subterranean waters on the paintings.” The group’s next aim would be to “map the murals on a large scale to see the extent of the salts and also to be able to determine the steps to be followed by the conservation staff when they unearth a mural painting”, she added.

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Dr Maite Maguregui of the IBeA group taking measurements in the mural paintings of Pompeii using portable tools. IBeA / UPV/EHU

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Article Source: UNIVERSITY OF THE BASQUE COUNTRY news release

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Archaeology: Neanderthal thumbs better adapted to holding tools with handles

SCIENTIFIC REPORTS—Neanderthal thumbs were better adapted to holding tools in the same way that we hold a hammer, according to a paper published in Scientific Reports. The findings suggest that Neanderthals may have found precision grips — where objects are held between the tip of the finger and thumb — more challenging than power ‘squeeze’ grips, where objects are held like a hammer, between the fingers and the palm with the thumb directing force.

Using 3D analysis, Ameline Bardo and colleagues mapped the joints between the bones responsible for movement of the thumb — referred to collectively as the trapeziometacarpal complex — of five Neanderthal individuals, and compared the results to measurements taken from the remains of five early modern humans and 50 recent modern adults.

The authors found covariation in shape and relative orientation of the trapeziometacarpal complex joints that suggest different repetitive thumb movements in Neanderthals compared with modern humans. The joint at the base of the thumb of the Neanderthal remains is flatter with a smaller contact surface, and better suited to an extended thumb positioned alongside the side of the hand. This thumb posture suggests the regular use of power ‘squeeze’ grips, like the ones we now use to hold tools with handles. In comparison, these joint surfaces are generally larger and more curved in recent modern human thumbs, an advantage when gripping objects between the pads of the finger and thumb, known as a precision grip.

Although the morphology of the studied Neanderthals is better suited for power ‘squeeze’ grips, they would still have been capable of precision hand postures, but would have found this more challenging than modern humans, according to the authors.

Comparison of fossil morphology between the hands of Neanderthals and modern humans may provide further insight into the behaviors of our ancient relatives and early tool use.

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Neanderthals were better suited to power ‘squeeze’ grips. Neanderthal-Museum, Mettmann. Creative Commons Attribution-ShareAlike International

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Article Source: SCIENTIFIC REPORTS news release

*The implications of thumb movements for Neanderthal and modern human manipulation. 10.1038/s41598-020-75694-2

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First exhaustive review of fossils recovered from Iberian archaeological sites

UNIVERSITY OF SEVILLE—Despite being rare, fossils nonetheless appear to be common elements in archaeological records. Their presence is documented at some of the main Iberian archaeological sites from the Palaeolithic (Altamira, Parpalló, Reclau Viver, Aitzbitarte, La Garma, Rascaño, El Juyo and La Pileta) to the Metal Ages (Los Millares, Valencina, Los Castillejos, El Argar, Fuente Álamo, Vila Nova de São Pedro, etc.).

An interdisciplinary research team, comprised of archaeologists, archaeozoologists, palaeontologists and geologists from the Autonomous Universities of Madrid, Málaga, Granada, Córdoba and the Basque Country, as well as from the Altamira National Museum and Research Centre and the Andalusian Earth Sciences Institute (CSIC), coordinated by the Department of Prehistory and Archaeology of the University of Seville, joined forces to tackle the largest fossils record thus far from archaeological sites in the Iberian Peninsula.

The researchers have analyzed a total of 633 specimens of scaphopods, molluscs, shark teeth and mammal remains from 82 archaeological sites in different regions (Andalusia, Asturias, Cantabria, Castile-La Mancha, Castile-Leon, Valencia, Madrid, Murcia and the Basque Country in Spain, and Alentejo, the Algarve, Extremadura, Lisbon and Setubal in Portugal).

The vast majority of fossils were collected from areas close to archaeological sites, suggesting their potential value as indicators of regional social and symbolic value during Iberian prehistory. However, there were changes throughout the period analyzed, indicating different cultural fashions and traditions.

The Iberian Peninsula has one of the richest paleontological records in Western Europe. However, “there were generally only scarce indications of the collection and use of fossils at Iberian sites during Prehistory, and thus the documentation of this behavior presented an anomalous situation compared to other regions of Europe, where numerous studies have been published on this practice,” explained Miguel Cortés, Professor of Prehistory at the University of Seville and leader of the study.

On the other hand, this confirms the need to take an interdisciplinary methodological approach to detect and study the fossils that are surely still awaiting analysis in the zooarchaeological collections of museums and institutions. In this sense, this work offers a new approach to archaeo-zoological records from archaeological sites, by identifying some cases where a review is needed.

“This work can serve to reappraise a little-known record and begin to solve the apparent anomaly of fossil collection by Iberian prehistoric communities compared to other areas of Western Europe,” added Dr. Cortés.

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Fossil oyster. Universidad de Sevilla

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Elephant fossil tooth. Universidad de Sevilla

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Shark fossil tooth. Universidad de Sevilla

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Article Source: UNIVERSITY OF SEVILLE news release

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Ancient people relied on coastal environments to survive the Last Glacial Maximum

ARIZONA STATE UNIVERSITY—Humans have a longstanding relationship with the sea that spans nearly 200,000 years. Researchers have long hypothesized that places like coastlines helped people mediate global shifts between glacial and interglacial conditions and the impact that these changes had on local environments and resources needed for their survival. Coastlines were so important to early humans that they may have even provided key routes for the dispersal of people out of Africa and across the world.

Two new multidisciplinary studies published in the journals Quaternary Science Reviews and Quaternary Research document persistent human occupation along the South African eastern seaboard from 35,000 years ago to 10,000 years ago. In this remote, and largely unstudied, location — known as the “Wild Coast” — researchers have used a suite of cutting-edge techniques to reconstruct what life was like during this inclement time and how people survived it.

The research is being conducted by an international and interdisciplinary collaboration of scientists studying coastal adaptations, diets and mobility of hunter-gatherers across glacial and interglacial phases of the Quaternary in coastal South Africa. The research team is led by Erich Fisher, Institute of Human Origins at Arizona State University; Hayley Cawthra with the South Africa Council for Geoscience and Nelson Mandela University; Irene Esteban, University of the Witwatersrand; and Justin Pargeter, New York University.

Together, these scientists have been leading excavations at the Mpondoland coastal rock shelter site known as Waterfall Bluff for the last five years. These excavations have uncovered evidence of human occupations from the end of the last ice age, approximately 35,000 years ago, through the complex transition to the modern time, known as the Holocene. Importantly, these researchers also found human occupations from the Last Glacial Maximum, which lasted from 26,000 to 19,000 years ago.

The Last Glacial Maximum was the period of maximum global ice volume, and it affected people and places around the world. It led to the formation of the Sahara desert and caused major reductions in Amazonian rainforest. In Siberia, the expansion of polar ice caps led to drops in global sea levels, creating a land bridge that allowed people to cross in to North America.

In southern Africa, archaeological records from this globally cold and dry time are rare because there were widespread movements of people as they abandoned increasingly inhospitable regions. Yet records of coastal occupation and foraging in southern Africa are even rarer. The drops in sea level during the Last Glacial Maximum and earlier glacial periods exposed an area on the continental shelf across southern Africa nearly as large as the island of Ireland. Hunter-gatherers wanting to remain near coastlines during these times had to trek out onto the exposed continental shelf. Yet these records are gone now, either destroyed by rising sea levels during warmer interglacial periods or submerged under the sea.

The research team — the Mpondoland Paleoclimate, Paleoenvironment, Paleoecology, and Paleoanthropology Project (P5 Project) — has hypothesized that places with narrow continental shelfs may preserve these missing records of glacial coastal occupation and foraging.

“The narrow shelf in Mpondoland was carved when the supercontinent Gondwana broke up and the Indian Ocean opened. When this happened, places with narrow continental shelfs restricted how far and how much the coastline would have changed over time,” said Hayley Cawthra.

In Mpondoland, a short section of the continental shelf is only 10 kilometers wide.

“That distance is less than how far we know past people often traveled in a day to get sea foods, meaning that no matter how much the sea levels dropped anytime in the past, the coastline was always accessible from the archaeological sites we have found on the modern Mpondoland coastline. It means that past people always had access to the sea, and we can see what they were doing because the evidence is still preserved today,” said Erich Fisher.

The oldest record of coastal foraging, which has also been found in southern Africa, shows that people relied on coastlines for food, water and move favorable living conditions over tens of thousands of years.

In the study published in the journal Quaternary Research, led by Erich Fisher, a multidisciplinary team of researchers documents the first direct evidence of coastal foraging in Africa during a glacial maximum and across a glacial/interglacial transition.

According to Fisher, “The work we are doing in Mpondoland is the latest in a long line of international and multidisciplinary research in South Africa revealing fantastic insights into human adaptations that often occurred at or near coastlines. Yet until now, no one had any idea what people were doing at the coast during glacial periods in southern Africa. Our records finally start to fill in these longstanding gaps and reveal a rich, but not exclusive, focus on the sea. Interestingly, we think it may have been the centralized location between land and sea and their plant and animal resources that attracted people and supported them amid repeated climatic and environmental variability.”

To date this evidence, P5 researchers collaborated with South Africa’s iThemba LABS and researchers at the Centre for Archaeological Science of the University of Wollongong to develop one of the highest-resolution chronologies at a southern Africa Late Pleistocene site, showing persistent human occupation and coastal resource use at Waterfall Bluff from 35,000 years ago to 10,000 years ago. This evidence, in the form of marine fish and shellfish remains, shows that prehistoric people repeatedly sought out dense and predictable seafoods.

This finding complements the results of a companion study published in the journal Quaternary Science Reviews, where paleobotanists and paleoclimatologists, led by Irene Esteban, used different lines of evidence to investigate interactions between prehistoric people’s plant-gathering strategies and climate and environmental changes over the last glacial/interglacial phase. This is the first multiproxy study in South Africa that combines preserved plant pollen, plant phytoliths, macro botanical remains (charcoal and plant fragments) and plant wax carbon and hydrogen isotopes from the same archaeological archive.

According to Irene Esteban, “It is not common to find such good preservation of different botanical remains, both of organic and inorganic origin, in the archaeological record.”

Each one of these records preserves a slightly different window to the past. It let the researchers compare different records to study how each one formed and what they represented, both individually and together.

“Ultimately,” said Esteban, “it allowed us to study interactions between hunter-gatherer plant-gathering strategies and environmental changes across a glacial-interglacial transition.”

Today, Mpondoland is characterized by afrotemperate and coastal forests as well as open woodlands that are interspersed with grasslands and wetlands. Each of these vegetation types supports different plant and animal resources. One of the key findings of this study is that these vegetation types persisted across glacial and interglacial periods albeit in varying amounts due to changes in sea levels, rainfall and temperature. The implication is that people living in Mpondoland in the past had access to an ever present and diverse suite of resources that let them survive here when they couldn’t in many other places across Africa.

Importantly, this study showed that people who lived at Waterfall Bluff collected wood from coastal vegetation communities during both glacial and interglacial phases. It is another link to the coastline for the people living at Waterfall Bluff during the Last Glacial Maximum. In fact, the exceptional quality of the archaeological and paleoenvironmental records demonstrates that those hunter-gatherers targeted different, but specific, coastal ecological niches all the while collecting terrestrial plant and animal resources from throughout the broader landscape and maintaining links to highland locales inland.

“The rich and diverse resource bases targeted by Mpondoland’s prehistoric hunter-gatherers speaks to our species’ unique generalist-specialist adaptations,” said Justin Pargeter. “These adaptions were key to our species ability to survive wide climate and environmental fluctuations while maintaining long-distance cultural and genetic connections.”

Together, these papers enrich our understanding about the adaptive strategies of people facing widespread climatic and environmental changes. They also provide a complementary perspective on hunter-gatherer behavioral responses to environmental shifts that is often biased by ethnographic research on African hunter-gatherers living in more marginal environments. In the case of Mpondoland, it is now evident that at least some people sought out the coast — probably because it provided centralized access to fresh water as well as both terrestrial and marine plant and animal resources, which supported their daily survival.

According to Esteban and Fisher, “These studies are just a drop in the ocean compared to the richness of the archaeological record we already know is preserved in Mpondoland. We have high expectations about what else we will discover there with our colleagues in South Africa and abroad when we can get back to the field safely in this post-COVID world.”

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Excavations at Waterfall Bluff, South Africa. Erich Fisher

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Waterfall Bluff view from the ocean. Erich Fisher

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Map of the Waterfall Bluff area in South Africa. Erich Fisher

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Article Source: ARIZONA STATE UNIVERSITY news release

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Native Californian rock art suggests hallucinogen use

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES—A study* finds evidence suggesting that a hallucinogenic plant was consumed at a rock art site and that the art is likely a representation of the plant. A long-established hypothesis holds that creators of rock art may have been in altered states of consciousness, but conclusive evidence of consumption of hallucinogens at rock art sites is lacking. David W. Robinson et al. analyzed fibrous bundles called quids, found in the ceiling of Pinwheel Cave in California. Because a pinwheel-like design painted on the cave resembles the flower Datura wrightii, which has known hallucinogenic properties and was used by Native Californians to induce trance states, the authors explored whether the quids might have contained Datura. Three-dimensional analysis of the quids suggested that they had been chewed, potentially inside the cave and under the paintings. Further analysis revealed the presence of the hallucinogenic compounds scopolamine and atropine in the quids, and scanning electron microscopy confirmed that the fibers in the quids came from Datura. The authors report that the paintings in the cave were likely not representations of the visual phenomena induced by Datura but, rather, representations of the plant itself that may have served to convey knowledge about the plant in preparation for a communal experience. According to the authors, the results both confirm the use of hallucinogens in rock art and challenge the previous model of the hallucinogens’ influence on the form of rock art.

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Digital image of Pinwheel painting, processed with an image enhancing technique called D-Stretch. Devlin Gandy

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Photograph of pinwheel painting with hallucinogenic Datura wrightii quid in crevice seen on the lower left next to the 10-cm scale. David Wayne Robinson

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Article Source: PNAS news release

*”Datura quids at Pinwheel Cave, California, provide unambiguous confirmation of the ingestion of hallucinogens at a rock art site ,” by David W. Robinson et al.

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Middle Stone Age populations repeatedly occupied West African coast

MAX PLANCK INSTITUTE FOR THE SCIENCE OF HUMAN HISTORY—Although coastlines have widely been proposed as potential corridors of past migration, the occupation of Africa’s tropical coasts during the Stone Age is poorly known, particularly in contrast to the temperate coasts of northern and southern Africa. Recent studies in eastern Africa have begun to resolve this, detailing dynamic behavioral changes near the coast of Kenya during the last glacial phase, but studies of Stone Age occupations along western Africa’s coasts are still lacking.

In recent years, anthropological research has begun to investigate the relationship between demographic diversity and patterns of behavioral change. A range of genetic and palaeoanthropological studies have begun to highlight the considerable demographic diversity present in West Africa in the recent past, but archaeological studies of Stone Age sites are still needed to understand how this diversity relates to patterns of behavior shown in the archaeological record.

“There are plenty of surface sites that have demonstrated the wealth of Stone Age archaeology in West Africa,” says Jimbob Blinkhorn of MPI-SHH, “but to characterize patterns of changing behavior, we need large, excavated stone tool assemblages that we can clearly date to specific periods.”

Tiémassas is a Stone Age site with a notable history of research, including surface surveys and early excavations in the mid-20th century, but the lack of systematic study meant it was mired in controversy.

“In the past, Tiémassas has been described as a Middle Stone Age, Later Stone Age or Neolithic site, and resolving between these alternatives has important implications for our understanding of behavior at the site,” says lead author Khady Niang of Université Cheikh Anta Diop de Dakar. “We’ve reviewed previously collected material from the site, conducted new excavations and analysis of stone tools and combined this with dating studies that make Tiémassas a benchmark example of the Middle Stone Age of West Africa.”

Previous research by the team dated a Middle Stone Age occupation at Tiémassas to 45 thousand years ago. The new research extends the timeframe of occupations at the site, with further stone tool assemblages recovered dating to 62 thousand and 25 thousand years ago. Critically, these stone tool assemblages contain technologically distinct types that help to characterize the nature of stone tool production during each occupation phase.

“The Middle Stone Age occupants of Tiémassas employed two distinct technologies – centripetal Levallois and discoidal reduction systems,” says Niang. “What is really notable is that the stone tool assemblages are really consistent with one another and form a pattern we can match up with the results of earlier excavations too. Pulled together, the site tells a clear story of startling technological continuity for nearly 40 thousand years.”

The results of this new research at Tiémassas consolidate the sparse record of Middle Stone Age occupations of West Africa. Yet, the site’s location is distinct from others dated to the Middle Stone Age in the region as it is located close to the coast and at the interface of three ecozones: savannahs, forests and mangroves.

“Our new work at Tiémassas offers a neat comparison to recent work on coastal occupations in eastern Africa. They span roughly the same timeframe, have similar ecological characteristics, and are found along tropical coasts,” says Blinkhorn. “But the continuity in behavior we see at Tiémassas stands in stark contrast to the technological changes observed in eastern Africa, and this reflects a similar pattern seen in genetic and palaeoanthropological studies of enduring population structure in West Africa.”

As director of fieldwork for the ‘Lise Meitner’ Pan-African Evolution research group’s aWARE project, Blinkhorn is conducting research in Senegal, Ivory Coast, Benin, and Nigeria, looking for connections between the environments of the past and recent human evolution.

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The excavation site at Tiémassas, which preserves evidence for Middle Stone Age occupations spanning 62-25 thousand years ago. K. Niang

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A Levallois core recovered from excavations at Tiémassas, part of a common, persistent suite of stone tool technologies employed at the site between 62-25 thousand years ago. K. Niang

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

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The microbiome of Da Vinci’s drawings

FRONTIERS—The work of Leonardo Da Vinci is an invaluable heritage of the 15th century. From engineering to anatomy, the master paved the way for many scientific disciplines. But what else could the drawings of Da Vinci teach us? Could molecular studies reveal interesting data from the past? These questions led an interdisciplinary team of researchers, curators and bioinformaticians, from both the University of Natural Resources and Life Science and the University of Applied Science of Wien in Austria, as well as the Central Institute for the Pathology of Archives and Books (ICPAL) in Italy, to collaborate and study the microbiome of seven different drawings of Leonardo Da Vinci. 

The molecular study of art pieces has already proved to be a valuable approach, and Dr Piñar, first author of the study, is not at her first try. In 2019, her team was able to investigate the storage conditions and even the possible geographical origin of three statues requisitioned from smugglers through the study of their microbiome and, earlier this year, the microbiome of ancient parchments allowed to elucidate the animal origin of the skins used for their manufacture 1,000 years ago. In the study presented here, the Austrian team is using an innovative genomic approach called Nanopore, considered as third-generation sequencing, to reveal for the first time the complete microbiome composition of several of Da Vinci’s drawings. The study is published today in Frontiers in Microbiology.

Overall, the results show a surprising dominance of bacteria over fungi. Until now, fungi were thought to be a dominant community in paper-supported art and tended to be the main focus of microbial analysis due to their biodeterioration potential. Here, a high proportion of these bacteria are either typical of the human microbiome, certainly introduced by intensive handling of the drawings during restoration works, or correspond to insects microbiomes, which could have been introduced, a long time ago, through flies and their excrements. 

A second interesting observation is the presence of a lot of human DNA. Unfortunately, we cannot assume that this DNA comes from the master himself but it might rather have been introduced by the restoration workers over the years. Finally, for both bacterial and fungal communities, correlation with the geographical location of the drawings can be observed. 

Altogether, the insects, the restoration workers, and the geographic localization seem to all have left a trace invisible to the eye on the drawings. While it is difficult to say if any of these contaminants originate from the time when Leonardo Da Vinci was sketching its drawings, Dr Piñar highlights the importance that tracking these data could have: “The sensitivity of the Nanopore sequencing method offers a great tool for the monitoring of objects of art. It allows the assessment of the microbiomes and the visualization of its variations due to detrimental situations. This can be used as a bio-archive of the objects’ history, providing a kind of fingerprint for current and future comparisons.” Thus, scientists could develop new methods to not only conserve the visual appearance of art but also to document the invisible journey of our artistic and cultural heritage.

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Da Vinci’s “Uomo della Bitta”. Piñar G, Sclocchi MC, Pinzari F, Colaizzi P, Graf A, Sebastiani ML and Sterflinger K (2020) The Microbiome of Leonardo da Vinci’s Drawings: A Bio-Archive of Their History. Front. Microbiol. 11:593401. doi: 10.3389/fmicb.2020.593401

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Sampling microbes from da Vinci’s Portrait of a Man in Red Chalk (1512). Piñar G, Sclocchi MC, Pinzari F, Colaizzi P, Graf A, Sebastiani ML and Sterflinger K (2020) The Microbiome of Leonardo da Vinci’s Drawings: A Bio-Archive of Their History. Front. Microbiol. 11:593401. doi: 10.3389/fmicb.2020.593401

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Sampling microbiome from Da Vinci’s “Studio di panneggio per una figura inginocchiata” (ca. 1475). Piñar G, Sclocchi MC, Pinzari F, Colaizzi P, Graf A, Sebastiani ML and Sterflinger K (2020) The Microbiome of Leonardo da Vinci’s Drawings: A Bio-Archive of Their History. Front. Microbiol. 11:593401. doi: 10.3389/fmicb.2020.593401

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Article Source: FRONTIERS news release

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Transition to feudal living in 14th century impacted local ecosystems

SCIENTIFIC REPORTS—The transition from tribal to feudal living, which occurred throughout the 14th century in Lagow, Poland had a significant impact on the local ecosystem, according to a study* published in Scientific Reports. The findings demonstrate how historical changes to human society and economies may have changed local environments.

Mariusz Lamentowicz and colleagues analysed changes in the composition of plants and pollen in different layers of peat in Pawski Lug, a nature reserve in Western Poland near the village of Lagow. Lagow was founded in the early 13th century and was settled by the Order of St. John of Jerusalem, Knights Hospitaller in 1350 CE.

By analyzing the composition of different peat layers, the authors were able to draw conclusions about the conditions that were present when each layer was formed. Based on the presence of beech and hornbeam trees, and water lilies in older, deeper layers, the authors concluded that prior to settlement by the Knights Hospitaller, Pawski Lug consisted of waterlogged land surrounded by pristine forest. The authors suggest that small amounts of charcoal present in the peat indicate that the forest was regularly burned on a small scale by the Slavic tribes that inhabited the area at the time.

Under the Knights Hospitaller, the majority of the land was given to agricultural labourers for farming. The authors found that the prevalence of hornbeam in peat from this era decreased as the abundance of cereals increased, indicating deforestation in favor of the establishment of croplands and meadows around the waterlogged land. The authors propose that deforestation may have affected the groundwater levels of Pawski Lug. Increased abundances of Scots pine trees indicate that this species recolonized the area. As a result, the soil became increasingly acidic, supporting the growth of peat moss which both acidified the habitat and aided peat formation.

The findings illustrate the direct and significant impact the economic transformation of Lagow from a tribal to a feudal society had on the local ecosystem.

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Amadis, Pixabay

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Article Source: Scientific Reports news release

*https://www.nature.com/articles/s41598-020-75692-4

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Geoscientists discover Ancestral Puebloans survived from ice melt in New Mexico lava tubes

UNIVERSITY OF SOUTH FLORIDA (USF INNOVATION), TAMPA, Fla. (Nov. 18, 2020)—For more than 10,000 years, the people who lived on the arid landscape of modern-day western New Mexico were renowned for their complex societies, unique architecture and early economic and political systems. But surviving in what Spanish explorers would later name El Malpais, or the “bad lands,” required ingenuity now being explained for the first time by an international geosciences team led by the University of South Florida.

Exploring an ice-laden lava tube of the El Malpais National Monument and using precisely radiocarbon- dated charcoal found preserved deep in an ice deposit in a lava tube, USF geosciences Professor Bogdan Onac and his team discovered that Ancestral Puebloans survived devastating droughts by traveling deep into the caves to melt ancient ice as a water resource.

Dating back as far as AD 150 to 950, the water gatherers left behind charred material in the cave indicating they started small fires to melt the ice to collect as drinking water or perhaps for religious rituals. Working in collaboration with colleagues from the National Park Service, the University of Minnesota and a research institute from Romania, the team published its discovery in “Scientific Reports.”

The droughts are believed to have influenced settlement and subsistence strategies, agricultural intensification, demographic trends and migration of the complex Ancestral Puebloan societies that once inhabited the American Southwest. Researchers claim the discovery from ice deposits presents “unambiguous evidence” of five drought events that impacted Ancestral Puebloan society during those centuries.

“This discovery sheds light on one of the many human-environment interactions in the Southwest at a time when climate change forced people to find water resources in unexpected places,” Onac said, noting that the geological conditions that supported the discovery are now threatened by modern climate change.

“The melting cave ice under current climate conditions is both uncovering and threatening a fragile source of paleoenvironmental and archaeological evidence,” he added.

Onac specializes in exploring the depths of caves around the world where ice and other geological formations and features provide a window to past sea level and climate conditions and help add important context to today’s climate challenges.

Their study focused on a single lava tube amid a 40-mile swatch of treacherous ancient lava flows that host numerous lava tubes, many with significant ice deposits. While archaeologists have suspected that some of the surface trails crisscrossing the lava flows were left by ancient inhabitants searching for water, the research team said their work is the earliest, directly dated proof of water harvesting within the lava tubes of the Southwest.

The study characterizes five drought periods over an 800-year period during which Ancestral Puebloans accessed the cave, whose entrance sits more than 2,200 meters above sea level and has been surveyed at a length of 171 meters long and about 14 meters in depth. The cave contains an ice block that appears to be a remnant of a much larger ice deposit that once filled most of the cave’s deepest section. For safety and conservation reasons, the National Park Service is identifying the site only as Cave 29.

In years with normal temperatures, the melting of seasonal ice near cave entrances would leave temporary shallow pools of water that would have been accessible to the Ancestral Puebloans. But when the ice was absent or retreated in warmer and dryer periods, the researchers documented evidence showing that the Ancestral Puebloans repeatedly worked their way to the back of the cave to light small fires to melt the ice block and capture the water.

They left behind charcoal and ash deposits, as well as a Cibola Gray Ware pottery shard that researchers found as they harvested a core of ancient ice from the block. The team believes the Ancestral Puebloans were able to manage smoke within the cave with its natural air circulation system by keeping the fires small.

The discovery was an unexpected one, Onac said. The team’s original goal in its journey into the lava tube was to gather samples to reconstruct the paleoclimate using ice deposits, which are slowly but steadily melting.

“I have entered many lava tubes, but this one was special because of the amount of charcoal present on the floor in the deeper part of the cave,” he said. “I thought it was an interesting topic, but only once we found charcoal and soot in the ice core that the idea to connect the use of ice as a water resource came to my mind.”

Unfortunately, researchers are now racing against the clock as modern climate conditions are causing the cave ice to melt, resulting in the loss of ancient climate data. Onac said he recently received support from the National Science Foundation to continue the research in the lava tubes before the geological evidence disappears.

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Entrance of the collapsed lava tube. University of South Florida

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Researchers descend into one of the lava tubes. University of South Florida

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Fragment of a Cibola Gray Ware. University of South Florida

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Joining in the exploration and research were Dylan S. Parmenter, whose master’s degree at USF was on the topic and is now a doctoral student at the University of Minnesota, Steven M. Baumann and Eric Weaver of the National Park Service, and Tiberiu B. Sava of the Horia Hulubei National Institute for Physics and Nuclear Engineering in Romania. The research was funded by the National Park Service and the National Science Foundation.

Article Source: UNIVERSITY OF SOUTH FLORIDA news release

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Teaching and complex tools ‘evolved together’

UNIVERSITY OF EXETER—The human ability to teach and our use of complex tools may have evolved together, according to new research.

The improvement of technologies across generations, known as “cumulative cultural evolution”, is central to our success as a species – but its origins are a mystery.

The new study, led by the University of Exeter, tested the power of teaching on the development of simple and more complex tools – and found teaching stands out when tackling complicated problems.

This suggests that, as early humans developed more complex tools, natural selection began to favour those who could teach.

“Humans have an unrivalled ability to pass knowledge down the generations,” said senior author Dr Alex Thornton, of the Centre for Ecology and Conservation on Exeter’s Penryn Campus in Cornwall.

“Traditional theories assumed that cumulative cultural evolution requires specialised processes, like teaching, to transmit information accurately, but this cannot explain why these processes evolved in the first place.

“Our aim in this study was to test the hypothesis that these processes gradually ‘co-evolved’ with an increasing reliance on complex tools.”

More than 600 people took part in the study, forming “chains” to develop a simple tool (a boat made of waterproof paper) or a more complex tool (a basket made of pipe cleaners).

All tools were used to carry marbles, with success measured by number of marbles carried.

The development chain involved ten “generations” – ten versions of the tool being made.

Each participant either saw the tool made by the previous person in the chain, watched the previous person make the tool (and could thus imitate and learn from them) or spoke to the previous participant – allowing teaching to take place.

“Simple and complex tools generally improved down the ‘generations’, and for simple tools this improvement was about the same in all three study conditions,” said Dr Amanda Lucas, of the University of Exeter.

“With complex tools, teaching consistently led to more improvement compared to other conditions.

“Teaching seemed to be particularly useful in allowing new, high-performing designs to be transmitted.”

Dr Lucas added: “We are incredibly grateful to local community groups across Cornwall who took part in the research, including Women’s Institutes, sports clubs, craft societies, museums, theatres, galleries, libraries and community gardeners.

“This meant that our study represented a diversity of ages, backgrounds and skills, which is important as many of these types of experiments, that intend to investigate something essential about being human, recruit a narrower sample of university students only.”

Dr Alex Thornton continued: “The effects we found were gradual – but the idea here was to look at the origins of cumulative cultural evolution, and over many generations these gradual improvements would add up.

“Our findings point to an evolutionary feedback loop between tool-making and teaching.

“This suggests that our ancestors could have started to make modest cumulative improvements to simple tools without the need for teaching, but as tools became more complex, teaching started to become advantageous.

“The evolution of improved teaching skills would in turn allow the production of even more complex and effective tools.”

The study also found that simple tools tended to “converge” towards a common design, while complex tools remained diverse and different – reflecting the diversity of technologies across human societies today.

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A tool to carry marbles, made by a participant in the study. University of Exeter

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Article Source: UNIVERSITY OF EXETER news release

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Ice Age Hunters in the Americas

While prehistoric hunters were following big game like bison and mammoth across ancient Eurasia during the peak of the last Ice Age, it seems there may have been contemporaries doing much the same thing thousands of miles and an entire ocean away in the Americas. In what is today called Europe, these ancient hunters represented defined cultures described in the archaeological literature as Aurignacian and Gravettian, leaving behind stone implements that included objects like worked bone and antler, fine blades and bladelets of flint, pointed blades and even the bow and arrow. In the Americas, however, contemporaneous stone tool technologies and other representative artifacts are yet ill-defined, as the number of sites that contain evidence of the American hunters’ presence during this very early time period are still few by comparison and have only been discovered in recent years, with other potential sites and locations still under exploration and investigation.

Who were these ancient Ice Age contemporaries in the Americas? Though the artifacts and other clues they left behind can arguably be dated back to at least 20,000 years ago, and perhaps even deeper into prehistory, scientists have yet to determine from whence they originally came, though many scholars hypothesize they originally migrated from points far to the north and east, on and across ancient Beringia and perhaps ultimately into Siberia and northeast Eurasia, if DNA studies of later Native Americans have any bearing.

Certainly there are far more questions than answers, but in coming years, archaeologists will continue to survey for new potential sites and return to old sites to re-explore and re-investigate with new tools, approaches and research objectives. 

Recent discoveries in the Yukon of Canada, Mexico, and other locations in South America are now emerging to tell the story of these American Ice Age hunter populations. In the article, America’s Ice Age Hunters, Popular Archaeology author James Kensington relates a narrative that details findings that may be up-ending long-held thoughts and assumptions about when the earliest humans arrived and thrived on the American continents.* 

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Northern Hemisphere glaciation during the last Ice Age (26,000 to 13,300 years ago). Hannes Grobe, Creative Commons  Attribution 2.5 Generic license, Wikimedia Commons

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*See the recently published subject article, available to Popular Archaeology premium subscribers.

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Newly discovered fossil shows small-scale evolutionary changes in an extinct human species

WASHINGTON UNIVERSITY IN ST. LOUIS—Males of the extinct human species Paranthropus robustus were thought to be substantially larger than females—much like the size differences seen in modern-day primates such as gorillas, orangutans and baboons. But a new fossil discovery in South Africa instead suggests that P. robustus evolved rapidly during a turbulent period of local climate change about 2 million years ago, resulting in anatomical changes that previously were attributed to sex.

An international research team including anthropologists at Washington University in St. Louis reported their discovery from the fossil-rich Drimolen cave system northwest of Johannesburg in the journal Nature Ecology & Evolution on Nov. 9*.

“This is the type of phenomenon that can be hard to document in the fossil record, especially with respect to early human evolution,” said David Strait, professor of biological anthropology in Arts & Sciences at Washington University.

The remarkably well-preserved fossil described in the paper was discovered by a student, Samantha Good, who participated in the Drimolen Cave Field School co-led by Strait.

Researchers already knew that the appearance of P. robustus in South Africa roughly coincided with the disappearance of Australopithecus, a somewhat more primitive early human, and the emergence in the region of early representatives of Homo, the genus to which modern people belong. This transition took place very rapidly, perhaps within only a few tens of thousands of years.

“The working hypothesis has been that climate change created stress in populations of Australopithecus leading eventually to their demise, but that environmental conditions were more favorable for Homo and Paranthropus, who may have dispersed into the region from elsewhere,” Strait said. “We now see that environmental conditions were probably stressful for Paranthropus as well, and that they needed to adapt to survive.”

The new specimen discovered at Drimolen, identified as DNH 155, is clearly a male but differs in important ways from other P. robustus previously discovered at the nearby site of Swartkrans—where most of the fossils of this species have been found.

Evolution within a species can be difficult to see in the fossil record. Changes may be subtle, and the fossil record is notoriously incomplete.

Usually, the fossil record reveals larger-scale patterns, such as when species or groups of species either appear in the fossil record or go extinct. So this Drimolen discovery provides a rarely seen window into early human evolution.

The new specimen is larger than a well-studied member of the species previously discovered at Drimolen—an individual known as DNH 7, and presumed to be female—but is measurably smaller than presumed males from Swartkrans.

“It now looks as if the difference between the two sites cannot simply be explained as differences between males and females, but rather as population-level differences between the sites,” said Jesse Martin, a doctoral student at La Trobe University and the co-first author of the study. “Our recent work has shown that Drimolen predates Swartkrans by about 200,000 years, so we believe that P. robustus evolved over time, with Drimolen representing an early population and Swartkrans representing a later, more anatomically derived population.”

“One can use the fossil record to help reconstruct the evolutionary relationships between species, and that pattern can provide all sorts of insights into the processes that shaped the evolution of particular groups,” Martin said. “But in the case of P. robustus, we can see discrete samples of the species drawn from the same geographic region but slightly different times exhibiting subtle anatomical differences, and that is consistent with change within a species.”

“It’s very important to be able to document evolutionary change within a lineage,” said Angeline Leece of La Trobe University, the other first author of the study. “It allows us to ask very focused questions about evolutionary processes. For example, we now know that tooth size changes over time in the species, which begs the question of why. There are reasons to believe that environmental changes placed these populations under dietary stress, and that points to future research that will let us test this possibility.”

Co-director of the Drimolen project, La Trobe University’s Andy Herries said, “Like all other creatures on earth, our ancestors adapted and evolved in accordance with the landscape and environment around them. For the first time in South Africa, we have the dating resolution and morphological evidence that allows us to see such changes in an ancient hominin lineage through a short window of time.”

The evidence of rapid but significant climate change during this period in South Africa comes from a variety of sources. Critically, fossils indicate that certain mammals associated with woodland or bushland environments went extinct or became less prevalent—while other species associated with drier, more open environments appeared locally for the first time.

P. robustus is remarkable in that it possesses a number of features in its cranium, jaws and teeth indicating that it was adapted to eat a diet consisting of either very hard or very tough foods,” Strait said. “We think that these adaptations allowed it to survive on foods that were mechanically difficult to eat as the environment changed to be cooler and drier, leading to changes in local vegetation.

“But the specimens from Drimolen exhibit skeletal features suggesting that their chewing muscles were positioned in such a way as to make them less able to bite and chew with as much force as the later P. robustus population from Swartkrans,” he said. “Over the course of 200,000 years, a dry climate likely led to natural selection favoring the evolution of a more efficient and powerful feeding apparatus in the species.”

Leece said it was notable that P. robustus appeared at roughly the same time as our direct ancestor Homo erectus, as documented by an infant H. erectus cranium that the team discovered at the same Drimolen site in 2015.

“These two vastly different species, H. erectus with their relatively large brains and small teeth, and P. robustus with their relatively large teeth and small brains, represent divergent evolutionary experiments,” Leece said. “While we were the lineage that won out in the end, the fossil record suggests that P. robustus was much more common than H. erectus on the landscape two million years ago.”

More broadly, the researchers think that this discovery serves as a cautionary tale for recognizing species in the fossil record.

A large number of fossil human species have been discovered over the past quarter century, and many of these new species designations are based on a small number of fossils from only one or a few sites in small geographic areas and narrow time ranges.

“We think that paleoanthropology needs to be a bit more critical about interpreting variation in anatomy as evidence for the presence of multiple species,” Strait said. “Depending on the ages of fossil samples, differences in bony anatomy might represent changes within lineages rather than evidence of multiple species.”

Project Co-Director Stephanie Baker of the University of Johannesburg added, “Drimolen is fast becoming a hotspot for early hominin discoveries, which is a testament to the current team’s dedication to holistic excavation and post-field analysis. The DNH 155 cranium is one of the best-preserved P. robustus specimens known to science. This is an example of what careful, fine-scale research can tell us about our distant ancestors.”

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The discovery of a remarkably well-preserved fossil from the extinct human species Paranthropus robustus suggests rapid evolution during a turbulent period of local climate change, resulting in anatomical changes that previously were attributed to sex. Jesse Martin and David Strait

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Article Source: WASHINGTON UNIVERSITY IN ST. LOUIS news release

*’Drimolen cranium DNH 155 documents microevolution in an early hominin species’, is published in Nature Ecology & Evolution on 09 November 2020. 

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If you liked this news, you may like Human Evolution’s Dustiest Jewel, The Remarkable Skulls of Drimolen, and Homo Erectus: The First Super Hominin, all in-depth, premium feature articles published at Popular Archaeology.

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Population dynamics and the rise of empires in Inner Asia

MAX PLANCK INSTITUTE FOR THE SCIENCE OF HUMAN HISTORY—From the late Bronze Age until the Middle Ages, the eastern Eurasian Steppe was home to a series of organized and highly influential nomadic empires. The Xiongnu (209 BCE – 98 CE) and Mongol (916-1125 CE) empires that bookend this period had especially large impacts on the demographics and geopolitics of Eurasia, but due to a lack of large-scale genetic studies, the origins, interactions, and relationships of the people who formed these states remains largely unknown.

To understand the population dynamics that gave rise to the Steppe’s historic empires, researchers from the Max Planck Institute for the Science of Human History (MPI-SHH), the National University of Mongolia, and partner institutions in Mongolia, Russia, Korea and the United States generated and analyzed genome-wide data for 214 individuals from 85 Mongolian and 3 Russian sites. Spanning the period of 4600 BCE to 1400 CE, it is among the largest studies of ancient Eastern and Inner Asian genomes to date.

During the mid-Holocene, the eastern Eurasian Steppe was populated by hunter-gatherers of Ancient Northeast Asian (ANA) and Ancient Northern Eurasian (ANE) ancestry, but around 3000 BCE, dairy pastoralism was introduced through the expansion of the Afanasievo culture of the Altai mountains, whose origins can be traced to the Yamnaya steppe herders of the Black Sea region more than 3,000 km to the west. Although these migrants left little genetic impact, they had an outsized cultural effect and by the Mid- to Late Bronze Age, dairy pastoralism was practiced by populations throughout the Eastern Steppe.

In the Late Bronze Age and Early Iron Age, populations in west, north and south-central Mongolia formed three distinct, geographically structured gene pools. These populations remained discrete for more than a millennium, until increased mobility, likely facilitated by the rise of horseback riding, began to break down this structure. The formation of the Xiongnu in north-central Mongolia, the first nomadic empire in Asia, is contemporaneous with this population mixture and with the influx of new gene pools originating from across Eurasia, from the Black Sea to China.

“Rather than a simple genetic turnover or replacement, the rise of the Xiongnu is linked to the sudden mixture of distinct populations that had been genetically separated for millennia. As a result, the Xiongnu of Mongolia show a spectacular level of genetic diversity that reflects much of Eurasia,” says Dr. Choongwon Jeong, lead author of the study and a professor of Biological Sciences at Seoul National University.

A thousand years later, individuals from the Mongol Empire, one of largest contiguous empires in history, showed a marked increase in Eastern Eurasian ancestry compared to individuals from the earlier Xiongnu, Turkic and Uyghur periods, accompanied by a near complete loss of the ancient ANE ancestry that had been present since before the Xiongnu Empire. By the end of the Mongol Empire, the genetic makeup of the Eastern Steppe had changed dramatically, ultimately stabilizing into the genetic profile observed among present-day Mongolians.

“Our study of ancient Mongolia reveals not only early genetic contributions from populations on the Western Steppe, but also a marked genetic shift towards eastern Eurasian ancestry during the Mongol Empire. The region has a remarkably dynamic genetic history, and ancient DNA is beginning to reveal the complexity of population events that have shaped the Eurasian Steppe,” says Ke Wang, co-first author of the study and a PhD student at the MPI-SHH.

In addition to the impacts of genetic events on political structures, the researchers also investigated the relationship between genetics and subsistence strategies. Despite more than 5,000 years of dairy pastoralism in the region and the continued importance of dairy in the average Mongolian diet today, researchers found no evidence for the selection of lactase persistence, a genetic trait that allows lactose digestion.

“The absence of lactase persistence in Mongolian populations both today and in the past challenges current medical models of lactose intolerance, and suggests a much more complicated prehistory of dairying. We are now turning to the gut microbiome to understand how populations adapt to dairy-based diets,” says Dr. Christina Warinner, senior author of the study, a professor of Anthropology at Harvard University and a research group leader at the MPI-SHH.

“Reconstructing a 6,000-year genetic history of Mongolia has had a transformative effect on our understanding of the archaeology of the region. While answering some long-standing questions, it has also generated new questions and revealed several surprises. We hope that this research will energize future work on the rich and complex relationships between ancestry, culture, technology, and politics in the rise of Asia’s nomadic empires,” adds Dr. Erdene Myagmar, co-senior author of the study and professor of Anthropology and Archaeology at the National University of Mongolia.

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A leaning Deer Stone placed in front of dozens of small stone mounds containing ritually-sacrificed horse burials at the Bronze Age monument site of Ikh Tsagaanii Am, Bayankhongor Province, central Mongolia. William Taylor

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Present-day home in the Mongolian countryside, known as a ger (Mongolian) or yurt (Russian). Christina Warinner

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

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Many early big-game hunters of the americas were female, researchers suggest

UNIVERSITY OF CALIFORNIA – DAVIS—For centuries, historians and scientists mostly agreed that when early human groups sought food, men hunted and women gathered. However, a 9,000-year-old female hunter burial in the Andes Mountains of South America reveals a different story, according to new research* conducted at the University of California, Davis.

“An archaeological discovery and analysis of early burial practices overturns the long-held ‘man-the-hunter’ hypothesis,” said Randy Haas, assistant professor of anthropology and the lead author of the study, “Female Hunters of the Early Americas.” It was published today (Nov. 4) in Science Advances.

“We believe that these findings are particularly timely in light of contemporary conversations surrounding gendered labor practices and inequality,” he added. “Labor practices among recent hunter-gatherer societies are highly gendered, which might lead some to believe that sexist inequalities in things like pay or rank are somehow ‘natural.’ But it’s now clear that sexual division of labor was fundamentally different — likely more equitable — in our species’ deep hunter-gatherer past.”

In 2018, during archaeological excavations at a high-altitude site called Wilamaya Patjxa in what is now Peru, researchers found an early burial that contained a hunting toolkit with projectile points and animal-processing tools. The objects accompanying people in death tend to be those that accompanied them in life, researchers said. It was determined that the hunter was likely female based on findings by the team’s osteologist, James Watson of The University of Arizona. Watson’s sex estimate was later confirmed by dental protein analysis conducted by UC Davis postdoctoral researcher Tammy Buonasera and Glendon Parker, an adjunct associate professor.

Revealing a broader pattern

The surprising discovery of an early female hunter burial led the team to ask whether she was part of a broader pattern of female hunters or merely a one-off. Looking at published records of late Pleistocene and early Holocene burials throughout North and South America, the researchers identified 429 individuals from 107 sites. Of those, 27 individuals were associated with big-game hunting tools — 11 were female and 15 were male. The sample was sufficient to “warrant the conclusion that female participation in early big-game hunting was likely nontrivial,” researchers said. Moreover, the analysis identified the Wilamaya Patjxa female hunter as the earliest hunter burial in the Americas.

Statistical analysis shows that somewhere between 30 to 50 percent of hunters in these populations were female, the study said. This level of participation stands in stark contrast to recent hunter-gatherers, and even farming and capitalist societies, where hunting is a decidedly male activity with low levels of female participation, certainly under 30 percent, Haas explained.

The study was conducted in collaboration with multiple UC Davis labs. Parker, a forensic expert in the Department of Environmental Toxicology, helped determine sex through a proteomic technique he recently developed. In Professor Jelmer Eerkens’ lab, Jenny Chen, an undergraduate researcher at the time of the study, discovered the distinct isotopic signature of meat consumption in the bones, further supporting the conclusion that the Wilamaya Patjxa female was a hunter.

While the research answers an old question about sexual division of labor in human societies, it also raises some new ones. The team now wishes to understand how sexual division of labor and its consequences in different times and places changed among hunter-gatherer populations in the Americas.

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Illustration of female hunter depicting hunters who may have appeared in the Andes 9,000 years ago. Matthew Verdolivo, UC Davis IET Academic Technology Services

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This illustration from the study shows tools recovered from the burial pit floor including projectile points (1 to 7), unmodified flakes (8 to 10), retouched flakes (11 to 13), a possible backed knife (14), thumbnail scrapers (15 and 16), scrapers/choppers (17 to 19), burnishing stones (17, 20, and 21), and red ocher nodules (22 to 24). Randy Haas/UC Davis

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A National Science Foundation grant contributed to this study.

Article Source: UNIVERSITY OF CALIFORNIA – DAVIS, news release

*https://doi.org/10.1126/sciadv.abd0310

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Neanderthal children grew and were weaned similar to us

UNIVERSITÀ DI BOLOGNA—Neanderthals behaved not so differently from us in raising their children, whose pace of growth was similar to Homo sapiens.

Thanks to the combination of geochemical and histological analyses of three Neanderthal milk teeth, researchers were able to determine their pace of growth and the weaning onset time. These teeth belonged to three different Neanderthal children who have lived between 70,000 and 45,000 years ago in a small area of Northeastern Italy.

Teeth grow and register information in form of growth lines – akin to tree rings – that can be read through histological techniques. Combining such information with chemical data obtained with a laser-mass spectrometer – in particular strontium concentrations – the scientists were able to show that these Neanderthals introduced solid food in their children’s diet at around 5-6 months of age.

NOT CULTURAL BUT PHYSIOLOGICAL

Alessia Nava (University of Kent, UK), co-first author of the work, says: “The beginning of weaning relates to physiology rather than to cultural factors. In modern humans, in fact, the first introduction of solid food occurs at around 6 months of age when the child needs a more energetic food supply, and it is shared by very different cultures and societies. Now, we know that also Neanderthals started to wean their children when modern humans do”.

“In particular, compared to other primates – says Federico Lugli (University of Bologna), co-first author of the work – it is highly conceivable that the high energy demand of the growing human brain triggers the early introduction of solid foods in child diet”.

Neanderthals are our closest cousins within the human evolutionary tree. However, their pace of growth and early life metabolic constraints are still highly debated within the scientific literature.

Stefano Benazzi (University of Bologna), co-senior author, says: “This work’s results imply similar energy demands during early infancy and a close pace of growth between Homo sapiens and Neanderthals. Taken together, these factors possibly suggest that Neanderthal newborns were of similar weight to modern human neonates, pointing to a likely similar gestational history and early-life ontogeny, and potentially shorter inter-birth interval”.

HOME SWEET HOME

The three milk teeth analyzed in this study were found in a limited area of Northeastern Italy, between the current provinces of Vicenza and Verona: in the Broion Cave, in the Fumane Cave and in the De Nadale Cave. Other than their early diet and growth, scientists also collected data on the regional mobility of these Neanderthals using time-resolved strontium isotope analyses.

“They were less mobile than previously suggested by other scholars”, says Wolfgang Müller (Goethe University Frankfurt), co-senior author. “The strontium isotope signature registered in their teeth indicates in fact that they have spent most of the time close to their home: this reflects a very modern mental template and a likely thoughtful use of local resources”.

“Despite the general cooling during the period of interest, Northeastern Italy has almost always been a place rich in food, ecological variability and caves, ultimately explaining the survival of Neanderthals in this region till about 45,000 years ago”, says Marco Peresani (University of Ferrara), co-senior author and responsible for findings from archaeological excavations at sites of De Nadale and Fumane.

This research adds a new piece in the puzzling pictures of Neanderthal, a human species so close to us but still so enigmatic. Specifically, researchers exclude that the Neanderthal small population size, derived in earlier genetic analyses, was driven by differences in weaning age and that other biocultural factors led to their demise.

This will be further investigated within the framework of the ERC project SUCCESS (The Earliest Migration of Homo sapiens in Southern Europe – Understanding the biocultural processes that define our uniqueness), led by Stefano Benazzi at the University of Bologna.

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Thanks to the combination of geochemical and histological analyses of these three Neanderthal milk teeth, researchers were able to determine their pace of growth and the weaning onset time. Federico Lugli

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Article Source: UNIVERSITÀ DI BOLOGNA news release

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New discoveries shed light on understanding admixture of ancient human species in Eurasia

American Association for the Advancement of Science, Max Planck Institute for Evolutionary Anthropology, Arizona State University—In two studies, researchers provide evidence that expands our understanding of modern humans in Eurasia and their interactions with their most elusive cousins, the Denisovans. While admixture between humans and Denisovans is widely recognized, physical remains of the archaic hominin species are exceedingly rare. What’s more, ancient genomic evidence from early modern humans in eastern Asia, which would capture the nature of admixture events between the two species and inform on humans’ timing and movement into and across Asia, is lacking. Research conducted by separate teams has provided additional insight into early human population history in Eurasia.

Denisovan DNA in the Genome of Early East Asians

Max Planck Institute for Evolutionary Anthropology—In 2006, miners discovered a hominin skullcap with peculiar morphological features in the Salkhit Valley of the Norovlin county in eastern Mongolia. It was initially referred to as Mongolanthropus and thought to be a Neanderthal or even a Homo erectus. The remains of the “Salkhit” individual represent the only Pleistocene hominin fossil found in the country.

Ancient DNA extracted from the skullcap shows that it belonged to a female modern human who lived 34,000 ago and was more related to Asians than to Europeans. Comparisons to the only other early East Asian individual genetically studied to date, a 40,000-year-old male from Tianyuan Cave outside Beijing (China), show that the two individuals are related to each other. However, they differ insofar that a quarter of the ancestry of the Salkhit individual derived from western Eurasians, probably via admixture with ancient Siberians.

Migration and interaction

“This is direct evidence that modern human communities in East Asia were already quite cosmopolitan earlier than 34,000 years ago”, says Diyendo Massilani, lead author of the study and researcher at the Max-Planck Institute for Evolutionary Anthropology. “This rare specimen shows that migration and interactions among populations across Eurasia happened frequently already some 35,000 years ago”.

The researchers used a new method developed at the Max-Planck Institute for Evolutionary Anthropology to find segments of DNA from extinct hominins in the Salkhit and Tianyuan genomes. They found that the two genomes contain not only Neanderthal DNA but also DNA from Denisovans, an elusive Asian relative of Neanderthals. “It is fascinating to see that the ancestors of the oldest humans in East Asia from whom we have been able to obtain genetic data had already mixed with Denisovans, an extinct form of hominins that has contributed ancestry to present-day populations in Asia and Oceania”, says Byambaa Gunchinsuren, a researcher at the Institute of Archaeology of the Mongolian Academy of Sciences. “This is direct evidence that Denisovans and modern humans had met and mixed more than 40,000 years ago”.

“Interestingly, the Denisovan DNA fragments in these very old East Asians overlap with Denisovan DNA fragments in the genomes of present-day populations in East Asia but not with Denisovan DNA fragments in Oceanians. This supports a model of multiple independent mixture events between Denisovans and modern humans”, says Massilani.

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The skullcap found in the Salkhit Valley in eastern Mongolia belonged to a woman who lived 34,000 years ago. Analyses showed: She had inherited about 25 percent of her DNA from Western Eurasian. Institute of Archaeology, Mongolian Academy of Sciences

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New Denisovan DNA expands diversity, history of species

Arizona State University—While the continents of Africa and Europe have been obvious and fruitful treasure troves for exploration and discovery of our modern human origins, Asia has been somewhat overlooked. Scientists have thought that modern humans left Africa about 60,000 years ago and, as they colonized Western Eurasia, found a world empty of any other archaic hominin species. This assumption stemmed in part from the fact that the prehistory of Asia is poorly known compared to that of Africa and Europe.

But research* published this week in the journal Science adds more evidence to the record that Denisovans, a group of extinct hominins that diverged from Neanderthals about 400,000 years ago, may have more widely inhabited northeast central Asia. Ancient Denisovan mitochondrial DNA has been recovered in sediments from Baishiya Karst Cave, a limestone cave at the northeast margin of the Tibetan Plateau, 3280 meters above sea level. Samples of sediments were analyzed by an international team including ASU researcher Charles Perreault. Denisovan mitochondrial DNA was recovered that have been dated from around 100,000 to 60,000 years ago, and also possibly as recently as 45,000. If true, this last date may overlap with the presence of modern humans in northeast central Asia.

Perreault is a research affiliate with the Arizona State University Institute of Human Origins and an associate professor with the School of Human Evolution and Social Change.

“When we started developing this project about 10 years ago,” said Perreault, “none of us expected Baishya Cave to be such a rich site. We’ve barely scratched the surface — three small excavation units have yielded hundreds of stone tools, fauna and ancient DNA. There’s a lot that remains to be done.”

A mandible fossil (the “Xiahe mandible”) from the same cave and dated to 160,000, had been previously identified, tenuously, as Denisovan, based on a single amino acid position. This current study dispels any doubt left that the Denisovans occupied the cave.

This discovery in Baishiya Karst Cave is the first time Denisovan DNA has been recovered from a location that is outside Denisova Cave in Siberia, Russia — previously the single location in the world where a handful of DNA-bearing Denisovan fossil bones have been discovered. In 2010, a fingerbone belonging to a previously unknown hominin species was found buried in Denisova Cave in the Russian Altai Mountains. Evidence of this new species forced anthropologists to revise their model of human evolution outside of Africa.

Finding Denisovan DNA on the Tibetan Plateau itself is surprising. Evidence of archaic hominins 2000 meters above sea level is unusual. Life this high on the plateau is harsh for many reasons, including its thin air, and humans can develop altitude sickness anywhere above 2500 meters above sea level. This suggests that the Denisovans may have evolved adaptations to high altitude, much like modern Tibetans. The dates of the sediments with mitochondrial DNA, along with the older 160,000-year-old Xiahe mandible, suggest that the Denisovans have been on the Plateau perhaps continuously for tens of thousands of years — more than enough for genetic adaptations to emerge.

Getting DNA samples from geographic locations outside of Siberia is also important to understand the genetic diversity and the population structure and history of the Denisovan group as a whole. Researchers suspected that Denisovans were widespread in Asia, based on the widespread Denisovan genomic signal among present-day Asians.

The Denisovan fossil and the DNA it contained, indicate that early modern humans coexisted in Asia with other archaic hominin species, but, unexpectedly, that they interbred with them. Like Neanderthals, Denisovan population intermixed with modern humans as they dispersed into Asia. In fact, there’s evidence that the genetic adaptations to high altitude in present-day Tibetans come from Denisovans. If confirmed, this is a great example of how intermixing with local archaic populations has shaped, and helped, the spread of modern humans around the world. In this case, it allowed humans to colonize the Tibetan Plateau perhaps faster than they would otherwise have been able to.

“Baishiya Cave is an extraordinary site that hold tremendous potential to understand human origins in Asia,” said Charles Perreault. “Future work in Baishiya Cave may give us a truly unique access to Denisovan behavior and solidifies the picture that is emerging, which is that Denisovans, like Neanderthals, were not mere offshoots of the human family tree — they were part of a web of now-extinct populations that contributed to the current human gene pool and shaped the evolution of our species in ways that we are only beginning to understand.”

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Tibet cave site. Charles Perreault

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*”Denisovana DNA in Late Pleistocene sediments from Baishiya Kartst Cave on the Tibetan Plateau,” Science. Dongju Zhang et al.

Article Sources: American Association for the Advancement of Science, Max Planck Institute for Evolutionary Anthropology, and Arizona State University news releases

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