Oldest flaked stone tools point to the repeated invention of stone tools

Oldest flaked stone tools point to the repeated invention of stone tools

stone tools
A large green artifact found in situ at the Bokol Dora site. Right: Image of the same artifact and a three dimensional model of the same artifact. Credit: David R. Braun

A new archaeological site discovered by an international and local team of scientists working in Ethiopia shows that the origins of stone tool production are older than 2.58 million years ago. Previously, the oldest evidence for systematic stone tool production and use was 2.58 to 2.55 million years ago.

Analysis by the researchers of early stone age sites, published this week in the Proceedings of the National Academy of Sciences, suggests that stone tools may have been invented many times in many ways before becoming an essential part of the human lineage.

The excavation site, known as Bokol Dora 1 or BD 1, is close to the 2013 discovery of the oldest fossil attributed to our genus Homo discovered at Ledi-Geraru in the Afar region of northeastern Ethiopia. The fossil, a jaw bone, dates to about 2.78 million years ago, some 200,000 years before the then oldest flaked stone tools. The Ledi-Geraru team has been working for the last five years to find out if there is a connection between the origins of our genus and the origins of systematic stone tool manufacture.

A significant step forward in this search was uncovered when Arizona State University geologist Christopher Campisano saw sharp-edged stone tools sticking out of the sediments on a steep, eroded slope.

Archaeologists from the Max Planck Institute, and the Ethiopian Authority for Research and the Conservation of Cultural Heritage as well as geologists from University of Algarve study the sediments at the Bokol Dora site. Stones were placed on the contact surface during the excavation to preserve the fragile stratigraphic contacts. Credit: Erin DiMaggio

"At first we found several artifacts lying on the surface, but we didn't know what sediments they were coming from," says Campisano. "But when I peered over the edge of a small cliff, I saw rocks sticking out from the mudstone face. I scaled up from the bottom using my rock hammer and found two nice stone tools starting to weather out."

It took several years to excavate through meters of sediments by hand before exposing an archaeological layer of animal bones and hundreds of small pieces of chipped stone representing the earliest evidence of our direct ancestors making and using stone knives. The site records a wealth of information about how and when humans began to use stone tools.

Preservation of the artifacts comes from originally being buried close to a water source.

"Looking at the sediments under a microscope, we could see that the site was exposed only for a very short time. These tools were dropped by early humans at the edge of a water source and then quickly buried. The site then stayed that way for millions of years," noted geoarchaeologist Vera Aldeias of the Interdisciplinary Center for Archaeology and Behavioral Evolution at the University of Algarve, Portugal.

Kaye Reed, who studies the site's ecology, is director of the Ledi-Geraru Research Project and a research associate with Arizona State University's Institute of Human Origins along with Campisano, notes that the animals found with these tools were similar to those found only a few kilometers away with the earliest Homo fossils.

Blade Engda of the University of Poitiers lifts an artifact from 2.6 million year old sediment exposing an imprint of the artifact on the ancient surface below. Credit: David R. Braun

"The early humans that made these stone tools lived in a totally different habitat than 'Lucy' did," says Reed. "Lucy" is the nickname for an older species of hominin known as Australopithecus afarensis, which was discovered at the site of Hadar, Ethiopia, about 45 kilometers southwest of the new BD 1 site. "The habitat changed from one of shrubland with occasional trees and riverine forests to open grasslands with few trees. Even the fossil giraffes were eating grass!"

In addition to dating a volcanic ash several meters below the site, project geologists analyzed the magnetic signature of the site's sediments. Over the Earth's history, its magnetic polarity has reversed at intervals that can be identified. Other earlier archaeological sites near the age of BD 1 are in "reversed" polarity sediments. The BD 1 site is in "normal" polarity sediments. The reversal from "normal" to "reversed" happened at about 2.58 million years ago, geologists knew that BD 1 was older than all the previously known sites.

The recent discovery of older hammering or "percussive" stone tools in Kenya dated to 3.3 million years ago, described as "Lomekwian," and butchered bones in Ethiopia shows the deep history of our ancestors making and using tools. However, recent discoveries of tools made by chimpanzees and monkeys have challenged "technological ape" ideas of human origins.

Archaeologists working at the BD 1 site wondered how their new stone tool discovery fit into this increasingly complex picture. What they found was that not only were these new tools the oldest artifacts yet ascribed to the "Oldowan," a technology originally named after finds from Olduvai Gorge in Tanzania, but also were distinct from tools made by chimpanzees, monkeys or even earlier human ancestors.

"We expected to see some indication of an evolution from the Lomekwian to these earliest Oldowan tools. Yet when we looked closely at the patterns, there was very little connection to what is known from older archaeological sites or to the tools modern primates are making," said Will Archer of the Max Planck Institute for Evolutionary Anthropology in Leipzig and the University of Cape Town.

The major differences appear to be the ability for our ancestors to systematically chip off smaller sharp-edged tools from larger nodules of stone. Chimpanzees and monkeys generally use tools for percussive activities, to hammer and bash food items like nuts and shellfish, which seems to have been the case with the 3.3 million year old Lomekwian tools as well.

Something changed by 2.6 million years ago, and our ancestors became more accurate and skilled at striking the edge of stones to make tools. The BD 1 artifacts captures this shift.

It appears that this shift in tool making occurred around the same time that our ancestor's teeth began to change. This can be seen in the Homo jaw from Ledi-Geraru. As our ancestors began to process food prior to eating using using stone tools, we start to see a reduction in the size of their teeth. Our technology and biology were intimately intertwined even as early as 2.6 million years ago.

The lack of clear connections with earlier stone tool technology suggests that tool use was invented multiple times in the past.

David Braun, an archaeologist with George Washington University and the lead author on the paper, noted, "Given that primate species throughout the world routinely use stone hammers to forage for new resources, it seems very possible that throughout Africa many different human ancestors found new ways of using stone artifacts to extract resources from their environment. If our hypothesis is correct then we would expect to find some type of continuity in artifact form after 2.6 million years ago, but not prior to this time period. We need to find more sites."

By 2.6 million years ago, there appears to be a long-term investment in tool use as part of the human condition.

Continued field investigations at the Ledi-Geraru project area are already producing more insights into the patterns of behavior in our earliest ancestors. New sites have already been found, and the Ledi-Geraru team will begin excavating them this year.

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This research was supported by the United States National Science Foundation and the John Templeton Foundation.

This research, "Earliest known Oldowan artifacts at >2.58 Ma from Ledi-Geraru, Ethiopia, highlight early technological diversity," is published in the Proceedings of the National Academy of Sciences.

 

Press release from the Arizona State University


Details of first historically recorded plague pandemic revealed by ancient genomes

Details of first historically recorded plague pandemic revealed by ancient genomes

Analysis of 8 new plague genomes from the first plague pandemic reveals previously unknown levels of plague diversity, and provides the first genetic evidence of the Justinianic Plague in the British Isles

Justinianic Plague Yersinia pestis
Map and phylogenetic tree showing the newly published (yellow) and previously published (turquoise) genomes. Shaded areas and dots represent historically recorded outbreaks of the First Pandemic. Credit: Marcel Keller

An international team of researchers has analyzed human remains from 21 archaeological sites to learn more about the impact and evolution of the plague-causing bacterium Yersinia pestis during the first plague pandemic (541-750 AD). In a study published in PNAS, the researchers reconstructed 8 plague genomes from Britain, Germany, France and Spain and uncovered a previously unknown level of diversity in Y. pestis strains. Additionally, they found the first direct genetic evidence of the Justinianic Plague in the British Isles.

The Justinianic Plague began in 541 in the Eastern Roman Empire, ruled at the time by the Emperor Justinian I, and recurrent outbreaks ravaged Europe and the Mediterranean basin for approximately 200 years. Contemporaneous records describe the extent of the pandemic, estimated to have wiped out up to 25% of the population of the Roman world at the time. Recent genetic studies revealed that the bacterium Yersinia pestis was the cause of the disease, but how it had spread and how the strains that appeared over the course of the pandemic were related to each other was previously unknown.

In the current study, an international team of researchers led by the Max Planck Institute for the Science of Human History analyzed human remains from 21 sites with multiple burials in Austria, Britain, Germany, France and Spain. They were able to reconstruct 8 new Y. pestis genomes, allowing them to compare these strains to previously published ancient and modern genomes. Additionally, the team found the earliest genetic evidence of plague in Britain, from the Anglo-Saxon site of Edix Hill. By using a combination of archaeological dating and the position of this strain of Y. pestis in its evolutionary tree, the researchers concluded that the genome is likely related to an ambiguously described pestilence in the British Isles in 544 AD.

High diversity of Y. pestis strains during the First Pandemic

The researchers found that there was a previously unknown diversity of strains of Y. pestis circulating in Europe between the 6th and 8th centuries AD. The 8 new genomes came from Britain, France, Germany and Spain. "The retrieval of genomes that span a wide geographic and temporal scope gives us the opportunity to assess Y. pestis' microdiversity present in Europe during the First Pandemic," explains co-first author Marcel Keller, PhD student at the Max Planck Institute for the Science of Human History, now working at the University of Tartu. The newly discovered genomes revealed that there were multiple, closely related strains of Y. pestis circulating during the 200 years of the First Pandemic, some possibly at the same times and in the same regions.

Despite the greatly increased number of genomes now available, the researchers were not able to clarify the onset of the Justinianic Plague. "The lineage likely emerged in Central Asia several hundred years before the First Pandemic, but we interpret the current data as insufficient to resolve the origin of the Justinianic Plague as a human epidemic, before it was first reported in Egypt in 541 AD. However, the fact that all genomes belong to the same lineage is indicative of a persistence of plague in Europe or the Mediterranean basin over this time period, instead of multiple reintroductions."

Sampling of a tooth from a suspected plague burial. Credit: Evelyn Guevara

Possible evidence of convergent evolution in strains from two independent historical pandemics

Another interesting finding of the study was that plague genomes appearing towards the end of the First Pandemic showed a big deletion in their genetic code that included two virulence factors. Plague genomes from the late stages of the Second Pandemic some 800-1000 years later show a similar deletion covering the same region of the genomes. "This is a possible example of convergent evolution, meaning that these Y. pestis strains independently evolved similar characteristics. Such changes may reflect an adaptation to a distinct ecological niche in Western Eurasia where the plague was circulating during both pandemics," explains co-first author Maria Spyrou of the Max Planck Institute for the Science of Human History.

The current study offers new insights into the first historically documented plague pandemic, and provides additional clues alongside historical, archaeological, and palaeoepidemiological evidence, helping to answer outstanding questions. "This study shows the potential of palaeogenomic research for understanding historical and modern pandemics by comparing genomes across millennia," explains senior author Johannes Krause of the Max Planck Institute for the Science of Human History. "With more extensive sampling of possible plague burials, we hope to contribute to the understanding of Y. pestis' microevolution and its impact on humans during the course of past and present pandemics."

Lunel-Viel (Languedoc-Southern France). Victim of the plague thrown into a demolition trench of a Gallo-Roman house; end of the 6th-early 7th century. Credit: 1990; CNRS - Claude Raynaud

Press release from the Max Planck Institute for the Science of Human History / Max-Planck-Instituts für Menschheitsgeschichte


ammonite amber

Coastal organisms trapped in 99-million-year-old amber

Coastal organisms trapped in 99-million-year-old amber

ammonite amber
Amber piece showing most large inclusions. Credit: NIGPAS

Most amber inclusions are organisms that lived in the forest. It is very rare to find sea life trapped in amber. However, an international research group led by Prof. WANG Bo from the Nanjing Institute of Geology and Palaeontology of the Chinese Academy of Sciences (NIGPAS) reported the first known ammonite trapped in amber in a study in PNAS published on May 13.

The ammonite, a kind of sea animal, was trapped in 99-million-year-old amber from northern Myanmar. The amber is 33 mm long, 9.5 mm wide, 29 mm high and weighs 6.08 g. Besides the ammonite, the amber also encases a diverse assemblage of organisms that today live on land or in the sea, including at least 40 individual animals.

Of the terrestrial fauna found in the amber, mites are the most abundant. Also present are spiders, millipedes, cockroaches, beetles, flies and wasps, most of which would have lived on the forest floor.

Of the marine fauna, in addition to the ammonite itself, sea snails and sea slaters are present. The slaters are like those living on the seashore today.

The researchers used X-ray micro-computed tomography (micro-CT) to obtain high-resolution three-dimensional images of the ammonite including its convoluted sutures, which are important for identifying ammonites.

They found that the ammonite is a juvenile Puzosia (Bhimaites) and its presence in the amber supports a late Albian-early Cenomanian age for the amber deposit. This discovery represents a rare example of dating using amber inclusions.

But how on earth did the ammonite, an extinct sea-dwelling relative of squid, get preserved in a piece of amber that also contains land-based animals? The ammonite and sea snail shells offer possible clues.

The shells are all empty with no soft-tissue, so the organisms were long dead by the time they were engulfed by resin. The outer shell of the ammonite is broken away and the entrance of the shell is full of sand. The amber also contains additional sand.

ammonite amber
(A) Lateral view under light microscopy. (B) Flattened sutures reconstructed by microtomography. (C) Microtomographic reconstruction, apparent view. (D) Microtomographic reconstruction, surface rendering; (E) Microtomographic reconstruction, virtual section. Credit: NIGPAS

The most likely explanation for the appearance of both marine and terrestrial organisms within the amber is that a sandy beach covered with shells was located close to resin-producing trees. The flying insects were trapped in the resin while it was still on the tree. As the resin flowed down the tree trunk, it trapped organisms that lived near the foot of the tree. Reaching the beach, it entombed shells and trapped the slaters living there.

 

Press release from the Chinese Academy of Sciences


ayahuasca Cueva del Chileno Bolivia

Ayahuasca fixings found in 1,000-year-old bundle in the Andes

Ayahuasca fixings found in 1,000-year-old bundle in the Andes

New evidence that the mind-blowing brew goes back millennia

ayahuasca Cueva del Chileno Bolivia
Ritual bundle with leather bag, carved wooden snuff tablets and snuff tube with human hair braids, pouch made of three fox snouts, camelid bone spatulas, colorful textile headband and wool and fiber strings. Credit: Photos courtesy of Juan Albarracín-Jordán and José Capriles.

Today's hipster creatives and entrepreneurs are hardly the first generation to partake of ayahuasca, according to archaeologists who have discovered traces of the powerfully hallucinogenic potion in a 1,000-year-old leather bundle buried in a cave in the Bolivian Andes.

Led by University of California, Berkeley, archaeologist Melanie Miller, a chemical analysis of a pouch made from three fox snouts sewn together tested positive for at least five plant-based psychoactive substances. They included dimethyltryptamine (DMT) and harmine, key active compounds in ayahuasca, a mind-blowing brew commonly associated with the Amazon jungle.

"This is the first evidence of ancient South Americans potentially combining different medicinal plants to produce a powerful substance like ayahuasca," said Miller, a researcher with UC Berkeley's Archaeological Research Facility who uses chemistry and various technologies to study how ancient humans lived.

She is lead author of the study, published today (Monday, May 6) in the journal Proceedings of the National Academy of Sciences.

Miller's analysis of a scraping from the fox-snout pouch and a plant sample found in the ritual bundle -- via liquid chromatography tandem mass spectrometry -- turned up trace amounts of bufotenine, DMT, harmine, cocaine and benzoylecgonine. Various combinations of these substances produce powerful, mind-altering hallucinations.

The discovery adds to a growing body of evidence of ritualistic psychotropic plant use going back millennia, said Miller, a postdoctoral fellow at the University of Otago in New Zealand who conducted the research during her doctoral studies at UC Berkeley.

"Our findings support the idea that people have been using these powerful plants for at least 1,000 years, combining them to go on a psychedelic journey, and that ayahuasca use may have roots in antiquity," said Miller.

The remarkably well-preserved ritual bundle was found by archaeologists at 13,000-foot elevations in the Lipez Altiplano region of southwestern Bolivia, where llamas and alpacas roam. The leather kit dates back to the pre-Inca Tiwanaku civilization, which dominated the southern Andean highlands from about 550 to 950 A.D.

In addition to the fox-snout pouch, the leather bundle contained intricately carved wooden "snuffing tablets" and a "snuffing tube" with human hair braids attached, for snorting intoxicants; llama bone spatulas; a colorful woven textile strip and dried plant material. All the objects were in good shape, due to the arid conditions of the Andean highlands.

Though the cave where the artifacts were found appeared to be a burial site, an excavation did not turn up human remains. Moreover, the plants found in the bundle do not grow at those altitudes, suggesting the bundle's owner may have been a traveling shaman or another expert in the rituals of psychotropic plant use, or someone who was part of an extensive medicinal plant trading network.

"A lot of these plants, if consumed in the wrong dosage, could be very poisonous," Miller said. "So, whoever owned this bundle would need to have had great knowledge and skills about how to use these plants, and how and where to procure them."

Of particular fascination to Miller is the pouch made of three fox snouts. She describes it as "the most amazing artifact I've had the privilege to work with."

"There are civilizations who believe that, by consuming certain psychotropic plants, you can embody a specific animal to help you reach supernatural realms, and perhaps a fox may be among those animals," Miller said.

Ayahuasca is made from brewing the vines of Banisteriopsis Caapi and the leaves of the chacruna (Psychotria viridis) shrub. The leaves release DMT, and the vines release harmine -- and therein lies the secret of the ayahuasca effect.

"The tryptamine DMT produces strong, vivid hallucinations that can last from minutes to an hour, but combined with harmine, you can have prolonged out-of-body altered states of consciousness with altered perceptions of time and of the self," Miller said.

Once the drugs take effect, ayahuasca users typically enter a purgative state, which means they vomit a lot.

Though its use is currently fashionable among Silicon Valley techies, Hollywood celebrities and spiritual awakening-seekers worldwide, Miller says these latest archaeological findings pay homage to ayahuasca's ancient history.

Miller joined the Cueva del Chileno excavation project when archaeologists Juan Albarracín-Jordán of the Universidad Mayor de San Andrés in Bolivia and José Capriles of Pennsylvania State University sought her expertise to identify the plant matter they had found in the bundle.

She traveled for two days to reach the cave site near the remote south Bolivian village of Lipez and helped with the final phases of the excavation. The bundle was transported to a laboratory in La Paz and, once permits were in place, samples were exported to the lab of Christine Moore, chief toxicologist with the Immunalysis Corp. in Pomona, California.

Moore's lab provided the liquid chromatography tandem mass spectrometry technology needed to conduct toxicology tests on the samples. Once the contents of the Andean bundle tested positive for five kinds of psychotropic substances, Miller's research team was over the moon.

"We were amazed to see the incredible preservation of these compounds in this ritual bundle," said Miller. "I feel very lucky to have been a part of this research."

 

Press release from University of California Berkeley

Ancient ritual bundle contained multiple psychotropic plants

ayahuasca Cueva del Chileno
The researchers found a ritual bundle in the Cueva del Chileno rock shelter located in southwestern Bolivia. Credit: Jose Capriles, Penn State

UNIVERSITY PARK, Pa. -- A thousand years ago, Native Americans in South America used multiple psychotropic plants -- possibly simultaneously -- to induce hallucinations and altered consciousness, according to an international team of anthropologists.

"We already knew that psychotropics were important in the spiritual and religious activities of the societies of the south-central Andes, but we did not know that these people were using so many different compounds and possibly combining them together," said Jose Capriles, assistant professor of anthropology, Penn State. "This is the largest number of psychoactive substances ever found in a single archaeological assemblage from South America."

The researchers were searching for ancient occupations in the dry rock shelters of the now-dry Sora River valley in southwestern Bolivia when they found a ritual bundle as part of a human burial. The bundle -- bound in a leather bag -- contained, among other things, two snuffing tablets (used to pulverize psychotropic plants into snuff), a snuffing tube (for smoking hallucinogenic plants), and a pouch constructed of three fox snouts.

The team used accelerator mass spectrometry radiocarbon dating to determine the age of the outer leather bag and found that it was about 1,000 years old.

"This period in this location is associated with the disintegration of the Tiwanaku state and the emergence of regional polities," said Capriles.

The team found psychoactive compounds in an animal-skin pouch constructed of three fox snouts stitched together. Credit: Jose Capriles, Penn State

In addition, the team used a scalpel to obtain a tiny scraping from the interior of the fox-snout pouch and analyzed the material using liquid chromatography with tandem mass spectrometry.

"This method is highly sensitive and very effective for detecting the presence of minute amounts of specific compounds from very small samples," said Melanie Miller, postdoctoral fellow at the University of Otago, New Zealand, and research affiliate at the University of California, Berkeley, who was responsible for analyzing the samples.

The researchers identified the presence of multiple psychoactive compounds -- cocaine, benzoylecgonine (the primary metabolite of cocaine), harmine, bufotenin, dimethyltryptamine (DMT) and possibly psilocin (a compound found in some mushrooms) -- from at least three different plant species (likely Erythroxylum coca, a species of Anadenanthera and Banistesteriopsis caani). The results will appear during the week of May 6 in Proceedings of the National Academy of Sciences.

According to Capriles, the fox-snout pouch likely belonged to a shaman.

"Shamans were ritual specialists who had knowledge of plants and how to use them as mechanisms to engage with supernatural beings, including venerated ancestors who were thought to exist in other realms," said Capriles. "It is possible that the shaman who owned this pouch consumed multiple different plants simultaneously to produce different effects or extend his or her hallucinations.'"

Capriles noted that the co-occurrence of harmine and DMT, which are the primary ingredients of ayahuasca -- a beverage that is reported to induce hallucinations and altered consciousness -- in the pouch suggests the use of this beverage as one of the drugs in the shaman's kit.

The ritual bundle included two carved and decorated wooden snuffing tablets that would have been used as a platform on which to pulverize psychotropic plants. Credit: Jose Capriles, Penn State

"Some scholars believe that ayahuasca has relatively recent origins, while others argue that it may have been used for centuries, or even millennia," said Capriles. "Given the presence of harmine and DMT together in the pouch we found, it is likely that this shaman ingested these simultaneously to achieve a hallucinogenic state, either through a beverage, such as ayahuasca, or through a composite snuff that contained these plants in a single mixture. This finding suggests that ayahuasca may have been used up to 1,000 years ago."

Not only does the presence of numerous compounds suggest simultaneous use of drugs and earlier use of ayahuasca, in particular, but it also indicates intricate botanical knowledge by the owner of the pouch and an effort to acquire hallucinogenic plants, as the plants came from different regions of mostly tropical South America.

"The presence of these compounds indicates the owner of this kit had access to at least three plants with psychoactive compounds, but potentially even four or five," said Miller. "None of the psychoactive compounds we found come from plants that grow in this area of the Andes, indicating either the presence of elaborate exchange networks or the movement of this individual across diverse environments to procure these special plants. This discovery reminds us that people in the past had extensive knowledge of these powerful plants and their potential uses, and they sought them out for their medicinal and psychoactive properties."

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Other authors on the paper include Juan Albarracin-Jordan, research associate, Universidad Mayor de San Andrés, Bolivia; and Christine Moore, chief toxicologist at Immunalysis Corporation.

The National Geographic Society Grant and the Bartolome de Las Casas Foundation supported this research.

Press release from Penn State

 


Middle Pleistocene asian Hualongdong Hualong cave

Middle Pleistocene human skull reveals variation and continuity in early Asian humans

Middle Pleistocene human skull reveals variation and continuity in early Asian humans

Middle Pleistocene asian Hualongdong
The Hualongdong Middle Pleistocene human skull and the collapsed cave site, with the fossil-bearing breccia in beige aournd the limestone blocks. Credit: WU Xiujie and Erik Trinkaus

A team of scientists led by LIU Wu and WU Xiujie from the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) of the Chinese Academy of Sciences reported the first ever Middle Pleistocene human skull found in southeastern China, revealing the variation and continuity in early Asian humans. Their findings were published on April 30 in Proceedings of the National Academy of Sciences (PNAS).

Excavations in Middle Pleistocene cave deposits in southeastern China yielded a largely complete skull that exhibits morphological similarities to other East Asian Middle and Late Pleistocene archaic human remains, but also foreshadows later modern human forms.

Fossil evidence for human evolution in East Asia during the Pleistocene is often fragmentary and scattered, which makes evaluating the pattern of archaic human evolution and modern human emergence in the region complicated.

Middle Pleistocene asian Hualongdong Hualong cave
The virtual reconstruction of the Hualongdong 6 human skull, with mirror-imaged portions in gray, plus two of the few stone tools from the site. Credit: WU Xiujie

WU Xiujie and his colleagues reported the recent discovery of most of a skull and associated remains dating to around 300,000 years ago in Hualong Cave (Hualongdong). The features of the Hualongdong fossils complement those of other East Asian remains in indicating a continuity of form through the Middle Pleistocene and into the Late Pleistocene.

In particular, the skull features a low and wide braincase with a projecting brow but a less prominent midface, as well as an incipient chin. The teeth are simple in form, contrasting with other archaic East Asian fossils, and its third molar is either reduced in size or absent.

According to the authors, the remains not only add to the expected variation of these Middle Pleistocene humans, recombining features present in other individuals from the same time period, but also foreshadow developments in modern humans, providing evidence for regional continuity.

 

Press release from the Chinese Academy of Sciences


Megalith tombs were family graves in European Stone Age

Megalith tombs were family graves in European Stone Age

In a new study published in the Proceedings of the National Academy of Sciences, an international research team, led from Uppsala University, discovered kin relationships among Stone Age individuals buried in megalithic tombs on Ireland and in Sweden. The kin relations can be traced for more than ten generations and suggests that megaliths were graves for kindred groups in Stone Age northwestern Europe.

Agriculture spread with migrants from the Fertile Crescent into Europe around 9,000 BCE, reaching northwestern Europe by 4,000 BCE. Starting around 4,500 BCE, a new phenomenon of constructing megalithic monuments, particularly for funerary practices, emerged along the Atlantic façade. These constructions have been enigmatic to the scientific community, and the origin and social structure of the groups that erected them has remained largely unknown. The international team sequenced and analysed the genomes from the human remains of 24 individuals from five megalithic burial sites, encompassing the widespread tradition of megalithic construction in northern and western Europe.

The team collected human remains of 24 individuals from megaliths on Ireland, in Scotland and the Baltic island of Gotland, Sweden. The remains were radiocarbon-dated to between 3,800 and 2,600 BCE. DNA was extracted from bones and teeth for genome sequencing. The team compared the genomic data to the genetic variation of Stone Age groups and individuals from other parts of Europe. The individuals in the megaliths were closely related to Neolithic farmers in northern and western Europe, and also to some groups in Iberia, but less related to farmer groups in central Europe.

Paternal continuity through time

The team found an overrepresentation of males compared to females in the megalith tombs on the British Isles. Credit: Göran Burenhult

The team found an overrepresentation of males compared to females in the megalith tombs on the British Isles.

"We found paternal continuity through time, including the same Y-chromosome haplotypes reoccurring over and over again," says archaeogeneticist Helena Malmström of Uppsala University and co-first author. "However, female kindred members were not excluded from the megalith burials as three of the six kinship relationships in these megaliths involved females."

A likely parent-offspring relation was discovered for individuals in the Listhogil Tomb at the Carrowmore site and Tomb 1 at Primrose Grange, about 2 km distance away from each other. Credit: Göran Burenhult

The genetic data show close kin relationships among the individuals buried within the megaliths. A likely parent-offspring relation was discovered for individuals in the Listhogil Tomb at the Carrowmore site and Tomb 1 at Primrose Grange, about 2 km distance away from each other. "This came as a surprise. It appears as these Neolithic societies were tightly knit with very close kin relations across burial sites," says population-geneticist Federico Sanchez-Quinto of Uppsala University and co-first author.

The Ansarve tomb was used by distinct groups

Megalith tombs Ansarve site Listhogil site Primrose Grange Carrowmore site archaeogenetics
The Ansarve site on the island of Gotland in the Baltic Sea is embedded in an area with mostly hunter-gathers at the time. Credit: Magdalena Fraser

The Ansarve site on the island of Gotland in the Baltic Sea is embedded in an area with mostly hunter-gathers at the time. "The people buried in the Ansarve tomb are remarkably different on a genetic level compared to the contemporaneous individuals excavated from hunter-gather-contexts, showing that the burial tradition in this megalithic tomb, which lasted for over 700 years, was performed by distinct groups with roots in the European Neolithic expansion," says archaeogeneticist Magdalena Fraser of Uppsala University and co-first author.

"That we find distinct paternal lineages among the people in the megaliths, an overrepresentation of males in some tombs, and the clear kindred relationships point to towards the individuals being part of a patrilineal segment of the society rather than representing a random sample from a larger Neolithic farmer community," says Mattias Jakobsson, population-geneticist at Uppsala University and senior author of the study.

"Our study demonstrates the potential in archaeogenetics to not only reveal large-scale migrations, but also inform about Stone Age societies and the role of particular phenomena in those times such as the megalith phenomena," says Federico Sanchez-Quinto.

"The patterns that we observe could be unique to the Primrose, Carrowmore, and Ansarve burials, and future studies of other megaliths are needed to tell whether this is a general pattern for megalith burials," says osteoarchaeologist Jan Storå of Stockholm University.

 

 

Publication

Sánchez-Quinto et al. (2019) Megalithic tombs in western and northern Neolithic Europe were linked to a kindred society, PNAS, DOI: 10.1073/pnas.1818037116 (Open access)
www.pnas.org/cgi/doi/10.1073/pnas.1818037116

Facts

This study is part of the Atlas project, a multidisciplinary effort to understand Eurasian and Scandinavian prehistory, funded by Riksbankens Jubileumsfond and the Knut and Alice Wallenberg foundation.

Press release from Uppsala University, by Linda Koffmar.