Showing posts with label Hunter-Gatherers. Show all posts
Showing posts with label Hunter-Gatherers. Show all posts

Feb 9, 2024

Scandinavia's first farmers slaughtered the hunter-gatherer population, study finds

Following the arrival of the first farmers in Scandinavia 5,900 years ago, the hunter-gatherer population was wiped out within a few generations, according to a new study from Lund University in Sweden, among others. The results, which are contrary to prevailing opinion, are based on DNA analysis of skeletons and teeth found in what is now Denmark.

The extensive study has been published as four separate articles in the journal Nature. An international research team, of which Lund University in Sweden is a member, has been able to draw new conclusions about the effects of migration on ancient populations by extracting DNA from skeletal parts and teeth of prehistoric people.

The study shows, among other things, that there have been two almost total population turnovers in Denmark over the past 7,300 years.

The first population change happened 5,900 years ago when a farmer population, with a different origin and appearance, drove out the gatherers, hunters and fishers who had previously populated Scandinavia.

Within a few generations, almost the entire hunter-gatherer population was wiped out.

"This transition has previously been presented as peaceful. However, our study indicates the opposite. In addition to violent death, it is likely that new pathogens from livestock finished off many gatherers," says Anne Birgitte Nielsen, geology researcher and head of the Radiocarbon Dating Laboratory at Lund University.

A thousand years later, about 4,850 years ago, another population change took place when people with genetic roots in Yamnaya -- a livestock herding people with origins in southern Russia -- came to Scandinavia and wiped out the previous farmer population.

Once again, this could have involved both violence and new pathogens.

These big-boned people pursued a semi-nomadic life on the steppes, tamed animals, kept domestic cattle and moved over large areas using horses and carts.

The people who settled in our climes were a mix between Yamnaya and Eastern European Neolithic people.

This genetic profile is dominant in today's Denmark, whereas the DNA profile of the first farmer population has been essentially erased.

"This time there was also a rapid population turnover, with virtually no descendants from the predecessors. We don't have as much DNA material from Sweden, but what there is points to a similar course of events. In other words, many Swedes are to a great extent also descendants of these semi-nomads," says Anne Birgitte Nielsen, who contributed quantitative pollen data which shows how the vegetation changed in connection with the population changes.

The results do not just overturn previous theories about amorous and peaceful meetings between groups of people.

The study also provides a deepened understanding of historical migration flows, and the interpretation of archaeological finds and changes in vegetation and land use found in palaeoecological data.

"Our results help to enhance our knowledge of our heredity and our understanding of the development of certain diseases. Something that in the long term could be beneficial, for example in medical research," concludes Anne Birgitte Nielsen.

Read more at Science Daily

Nov 7, 2023

Long-distance weaponry identified at the 31,000-year-old archaeological site of Maisières-Canal

The hunter-gatherers who settled on the banks of the Haine, a river in southern Belgium, 31,000 years ago were already using spearthrowers to hunt their game. This is the finding of a new study conducted at TraceoLab at the University of Liège. The material found at the archaeological site of Maisières-Canal permits establishing the use of this hunting technique 10,000 years earlier than the oldest currently known preserved spearthrowers. This discovery, published in the journal Nature Scientific Reports, is prompting archaeologists to reconsider the age of this important technological innovation.

The spearthrower is a weapon designed for throwing darts, which are large projectiles resembling arrows that generally measure over two metres long. Spearthrowers can propel darts over a distance of up to eighty metres. The invention of long-range hunting weapons has had significant consequences for human evolution, as it changed hunting practices and the dynamics between humans and their prey, as well as the diet and social organisation of prehistoric hunter-gatherer groups. The date of invention and spread of these weapons has therefore long been the subject of lively debate within the scientific community.

"Until now, the early weapons have been infamously hard to detect at archaeological sites because they were made of organic components that preserve rarely, explains Justin Coppe, researcher at TraceoLab. Stone points that armed ancient projectiles and that are much more frequently encountered at archaeological excavations have been difficult to connect to particular weapons reliably." Most recently published claims for early use of spearthrowers and bows in Europe and Africa have relied exclusively on projectile point size to link them to these weapon systems. However, ethnographic reviews and experimental testing have cast serious doubt on this line of reasoning by showing that arrow, dart, and spear tips can be highly variable in size, with overlapping ranges.

The innovative approach developed by the archaeologists at TraceoLab combines ballistic analysis and fracture mechanics to gain a better understanding of the traces preserved on the flint points. "We carried out a large-scale experiment in which we fired replicas of Palaeolithic projectiles using different weapons such as spears, bows and spearthrowers," explains Noora Taipale, FNRS research fellow at TraceoLab. By carefully examining the fractures on these stone points, we were able to understand how each weapon affected the fracturing of the points when they impacted the target." Each weapon left distinct marks on the stone points, enabling archaeologists to match these marks to archaeological finds. In a way, it's like identifying a gun from the marks the barrel leaves on a bullet, a practice known from forensic science.

Read more at Science Daily

Oct 23, 2023

Challenging prehistoric gender roles: Research finds that women were hunters, too

It's a familiar story to many of us: In prehistoric times, men were hunters and women were gatherers. Women were not physically capable of hunting because their anatomy was different from men. And because men were hunters, they drove human evolution.

But that story's not true, according to research by University of Delaware anthropology professor Sarah Lacy, which was recently published in Scientific American and in two papers in the journal American Anthropologist.

Lacy and her colleague Cara Ocobock from the University of Notre Dame examined the division of labor according to sex during the Paleolithic era, approximately 2.5 million to 12,000 years ago. Through a review of current archaeological evidence and literature, they found little evidence to support the idea that roles were assigned specifically to each sex. The team also looked at female physiology and found that women were not only physically capable of being hunters, but that there is little evidence to support that they were not hunting.

Lacy is a biological anthropologist who studies the health of early humans, and Ocobock is a physiologist who makes analogies between modern day and the fossil record. Friends in graduate school, they collaborated after "complaining about a number of papers that had come out that used this default null hypothesis that cavemen had strong gendered division of labor, the males hunt, females gather things. We were like, 'Why is that the default? We have so much evidence that that's not the case,'" Lacy said.

The researchers found examples of equality for both sexes in ancient tools, diet, art, burials and anatomy.

"People found things in the past and they just automatically gendered them male and didn't acknowledge the fact that everyone we found in the past has these markers, whether in their bones or in stone tools that are being placed in their burials. We can't really tell who made what, right? We can't say, 'Oh, only males flintknap,' because there's no signature left on the stone tool that tells us who made it," Lacy said, referring to the method by which stone tools were made. "But from what evidence we do have, there appears to be almost no sex differences in roles."

The team also examined the question of whether anatomical and physiological differences between men and women prevented women from hunting. They found that men have an advantage over women in activities requiring speed and power, such as sprinting and throwing, but that women have an advantage over men in activities requiring endurance, such as running. Both sets of activities were essential to hunting in ancient times.

The team highlighted the role of the hormone estrogen, which is more prominent in women than men, as a key component in conferring that advantage. Estrogen can increase fat metabolism, which gives muscles a longer-lasting energy source and can regulate muscle breakdown, preventing muscles from wearing down. Scientists have traced estrogen receptors, proteins that direct the hormone to the right place in the body, back to 600 million years ago.

"When we take a deeper look at the anatomy and the modern physiology and then actually look at the skeletal remains of ancient people, there's no difference in trauma patterns between males and females, because they're doing the same activities," Lacy said.

During the Paleolithic era, most people lived in small groups. To Lacy, the idea that only part of the group would hunt didn't make sense.

"You live in such a small society. You have to be really, really flexible," she said. "Everyone has to be able to pick up any role at any time. It just seems like the obvious thing, but people weren't taking it that way."

Man the Hunter

The theory of men as hunters and women as gatherers first gained notoriety in 1968, when anthropologists Richard B. Lee and Irven DeVore published Man the Hunter, a collection of scholarly papers presented at a symposium in 1966. The authors made the case that hunting advanced human evolution by adding meat to prehistoric diets, contributing to the growth of bigger brains, compared to our primate cousins. The authors assumed all hunters were male.

Lacy points to that gender bias by previous scholars as a reason why the concept became widely accepted in academia, eventually spreading to popular culture. Television cartoons, feature films, museum exhibits and textbooks reinforced the idea. When female scholars published research to the contrary, their work was largely ignored or devalued.

"There were women who were publishing about this in the '70s, '80s and '90s, but their work kept getting relegated to, 'Oh, that's a feminist critique or a feminist approach,'" Lacy said. "This was before any of the work on genetics and a lot of the work on physiology and the role of estrogen had come out. We wanted to both lift back up the arguments that they had already made and add to it all the new stuff."

Lacy said the "man the hunter" theory continues to influence the discipline. While she acknowledges that much more research needs to be done about the lives of prehistoric people -- especially women -- she hopes her view that labor was divided among both sexes will become the default approach for research in the future.

For 3 million years, males and females both participated in subsistence gathering for their communities, and dependence on meat and hunting was driven by both sexes, Lacy said.

Read more at Science Daily

Jul 27, 2023

Family trees from the European Neolithic

The Neolithic burial site of Gurgy 'les Noisats' in France revealed two unprecedentedly large family trees which allowed a Franco-German team to explore the social organization of the 6,700-year-old community. Based on multiple lines of evidence, the team describes a close kin group which practiced monogamy and female exogamy, and experienced generally stable times.

The Neolithic lifestyle, based on farming instead of hunting and gathering, emerged in the Near East around 12,000 years ago and contributed profoundly to the modern way of life. The ability to produce and store extra food led Neolithic people to develop new social customs built on wealth, and therefore form social hierarchies. After an early phase of diffusion and having reached regions in western Europe, settled societies became more complex, which is sometimes reflected in the funerary world as well. The Paris Basin region in northern modern-day France is known for its monumental funerary sites, understood as being built for the society's "elite." In this context, the site of Gurgy 'Les Noisats', one of the biggest Neolithic funerary sites without monument in the region, begs the question who these people buried with different practices were.

Using new methods for obtaining and analysing ancient DNA data, and by sampling nearly every individual from the flat cemetery, researchers from the PACEA laboratory in Bordeaux, France, and from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, reveal two massive family trees which open a window into the lives of the people of this prehistoric community.

Massive family trees

In their study, the scientists analysed genome-wide ancient DNA data from 94 individuals buried at Gurgy, combined with strontium isotope ratio values, mitochondrial DNA (maternal lineages) and Y-chromosome (paternal lineages) data, age-at-death, and genetic sex. Two family trees could be reconstructed, the first connecting 64 individuals over seven generations is the largest pedigree reconstructed from ancient DNA to date, while the second connects twelve individuals over five generations.

"Since the beginning of the excavation, we found evidence of a complete control of the funerary space and only very few overlapping burials, which felt like the site was managed by a group of closely related individuals, or at least by people who knew who was buried where," says Stéphane Rottier from the University of Bordeaux, the archaeo-anthropologist who excavated the site between 2004 and 2007. Indeed, a positive correlation between spatial and genetic distances showed that the deceased were likely to be buried close to a relative.

Insights into the social structure of Gurgy

Exploring the pedigrees revealed a strong patrilineal pattern, where each generation is almost exclusively linked to the previous generation through the biological father, which connects the entire group of Gurgy through the paternal line. At the same time, combined evidence from mitochondrial lineages and strontium stable isotope revealing a non-local origin of most women suggested the practice of patrilocality, meaning that the sons stayed where they were born, and had children with females from outside of Gurgy. Settling in with the male partner's home community is known as virilocality. By contrast, most of the lineage adult daughters are missing, in line with female exogamy, potentially indicating a reciprocal exchange system. Interestingly, these "new incoming" female individuals were only very distantly related to each other, meaning that they must have come from a network of nearby communities, instead of just one nearby group. This lends support to the existence of a relatively wide and potentially fluid exchange network comprising many (including smaller) groups.

Looking at the family trees, Maïté Rivollat, first author of the study, is amazed: "We observe a large number of full siblings who have reached reproductive age. Combined with the expected equal number of females and significant number of deceased infants, this indicates large family sizes, a high fertility rate and generally stable conditions of health and nutrition, which is quite striking for such ancient times." Another notably unique feature at Gurgy is a lack of half-siblings, suggesting neither polygamous nor serial monogamous reproductive partnerships (or the exclusion of offspring from these unions from the main cemetery), when compared to the so far only other example of union practices from Neolithic megaliths.

A founding ancestor

In the frame of this patrilocal system, one male individual from which everyone in the largest family tree was descended could be identified as the "founding father" of the cemetery. His burial is unique at the site, as his skeletal remains were buried as a secondary deposit inside the grave pit of a woman, for whom, unfortunately, no genomic data could be obtained. Therefore, his bones must have been brought from wherever he had originally died to be reburied at Gurgy. "He must have represented a person of great significance for the founders of the Gurgy site to be brought there after a primary burial somewhere else," explains Marie-France Deguilloux from the University of Bordeaux, co-senior author of the study.

Although the main pedigree spans seven generations, the demographic profile suggests that a large family group spanning several generations arrived at the site. With almost no subadults buried at the site during the first few generations, and by contrast no adult burials in the last generations, only a short use of the site is expected. The group must have left a previous site, leaving behind any previously deceased children but still brought the lineage father. Only a few generations later the same happened: the adult of the last generations left Gurgy for another place, leaving behind their own children. Hence, Gurgy was probably only used for three to four generations, or approximately one century.

Read more at Science Daily

May 15, 2023

Tooth enamel provides clues to hunter-gatherer lifestyle of Neanderthals

A study by an international team of researchers, led by the University of Southampton, has given an intriguing glimpse of the hunting habits and diets of Neanderthals and other humans living in western Europe.

The scientists examined chemical properties locked inside tooth enamel to piece together how pre-historic people lived off the land around the Almonda Cave system, near Torres Novas in central Portugal almost 100 thousand years ago.

Their findings, published in the journal PNAS, show Neanderthals in the region were hunting fairly large animals across wide tracts of land, whereas humans living in the same location tens of thousands of years later survived on smaller creatures in an area half the size.

Strontium isotopes in rocks gradually change over millions of years because of radioactive processes. This means they vary from place to place depending on the age of the underlying geology. As rocks weather, the isotopic 'fingerprints' are passed into plants via sediments, and make their way along the food chain -- eventually passing into tooth enamel.

In this study, archaeologists used a technique which laser samples enamel and makes thousands of individual strontium isotope measurements along the growth of a tooth crown. Samples were taken from two Neanderthals, dating back about 95,000 years, and from a more recent human who lived about 13,000 years ago, during the Magdalenian period.

The scientists also looked at isotopes in the tooth enamel of animals found in the cave system. Alongside strontium, they measured oxygen isotopes, which vary seasonally from summer to winter. This enabled them to establish not only where the animals ranged across the landscape, but in which seasons they were available for hunting.

The team showed that the Neanderthals, who were targeting large animals, could have hunted wild goat in the summer, whereas horses, red deer and an extinct form of rhinoceros were available all year round within about 30km of the cave. The Magdalenian individual showed a different pattern of subsistence, with seasonal movement of about 20km from the Almonda caves to the banks of the Tagus River, and a diet which included rabbits, red deer, wild goat and freshwater fish.

The researchers approximated the territory of the two different human groups, revealing contrasting results. The Neanderthals obtained their food over approximately 600 km2, whereas the Magdalenian individuals occupied a much smaller territory of about 300 km2.

Lead author, Dr Bethan Linscott who conducted the research while at the University of Southampton and who now works at the University of Oxford said: "Tooth enamel forms incrementally, and so represents a time series that records the geological origin of the food an individual ate.

"Using laser ablation, we can measure the variation of strontium isotopes over the two or three years it takes for the enamel to form. By comparing the strontium isotopes in the teeth with sediments collected at different locations in the region, we were able to map the movements of the Neanderthals and the Magdalenian individual. The geology around the Almonda caves is highly variable, making it possible to spot movement of just a few kms."

Co-author, Professor Alistair Pike of the University of Southampton, who supervised the research said: "This study shows just how much science has changed our understanding of archaeology in the past decade. Previously, the lives and behaviours of past individuals was limited to what we could infer from marks on their bones or the artefacts they used. Now, using the chemistry of bones and teeth, we can begin to reconstruct individual life histories, even as far back as the Neanderthals."

Read more at Science Daily

Mar 24, 2023

Ancient genomes reveal immunity adaptation in early farmers

Research from the Francis Crick Institute published today in Current Biology has revealed that diversity in genes coding for immunity may have facilitated adaptation to farming lifestyles in prehistoric periods.

Researchers at the Ancient Genomics Laboratory at the Crick studied available genome-wide DNA from 677 individuals dating to Stone Age Europe, spanning the movement of Neolithic farmers from the Near East into Europe about 8000 years ago, where they mixed with Mesolithic hunter-gatherers already in Europe.

They were interested in whether any particular genes might have coded for adaptations important to early farming groups, and looked for evidence of rapid evolution in these populations.

Since about 20% of the ancestry of descendant late Stone Age people could be traced to the local European hunter-gatherers, the researchers also asked whether any particular genes showed evidence of more hunter-gatherer ancestry.

They found that a large genetic region responsible for immune responses to diseases -- the major histocompatibility complex (MHC) -- showed both the strongest evidence of rapid evolution, and more Mesolithic hunter-gatherer ancestry than expected, suggesting that genetic variants in the MHC region already present in Europe were passed down preferentially.

It has previously been thought that the transition to farming was associated with increased natural selection on immunity variants, as people started living closer to animals and eating more animal products. This research supports this view, but also shows that diversity in immune genes may be just as important as adaptation to lifestyle.

The research team speculates that either the hunter-gatherers already had genetic adaptations against bacteria, viruses or other microorganisms in Europe, or that having many different forms of the genes was advantageous.

Tom Davy, PhD student at the Francis Crick Institute and lead author, said: "It was really exciting to see for the first time that immunity is important for the transition to farming in a prehistoric population. The later Neolithic people had far more farmer ancestry in general, so we expected to see the same at the MHC region, especially as many diseases have been linked to Neolithic periods. But we saw about 50:50 ancestry from Neolithic farmers and Mesolithic hunter-gatherers here, showing that natural selection favoured genes from the hunter-gatherers already in Europe.

"At the moment we're not quite sure whythis happened, but a proposal is that the European hunter-gatherers had genetic variations which allowed them to fight Europe-specific diseases. Or picking up a variety of genes from both hunter-gatherers and farmers was beneficial because it resulted in lots of diversity at this major group of genes, allowing people to better fight off disease."

The team also confirmed results from previous studies, showing that genes coding for skin pigmentation showed the greatest representation for Neolithic farmer ancestry, with these variations coming into Europe from the Near East. This may be to maintain vitamin D levels when sources, such as diet and exposure to sunlight, change.

Pontus Skoglund, Group Leader of the Ancient Genomics Laboratory at the Crick, said: "The shift to farming was an important transition all over the world, resulting in changing diets and exposure to infectious disease.

Read more at Science Daily

Mar 8, 2023

Hunter-gatherer childhoods may offer clues to improving education and wellbeing in developed countries

Hunter-gatherers can help us understand the conditions that children may be psychologically adapted to because we lived as hunter-gatherers for 95% of our evolutionary history. And paying greater attention to hunter-gatherer childhoods may help economically developed countries improve education and wellbeing.

Published today in the Journal of Child Psychology and Psychiatry, a new study by Dr Nikhil Chaudhary, an evolutionary anthropologist at the University of Cambridge, and Dr Annie Swanepoel, a child psychiatrist, calls for new research into child mental health in hunter-gatherer societies. They explore the possibility that some common aspects of hunter-gatherer childhoods could help families in economically developed countries. Eventually, hunter-gatherer behaviours could inform 'experimental intervention trials' in homes, schools and nurseries.

The authors acknowledge that children living in hunter-gatherer societies live in very different environments and circumstances than those in developed countries. They also stress that hunter-gatherer children invariably face many difficulties that are not experienced in developed countries and, therefore, caution that these childhoods should not be idealised.

Drawing on his own observations of the BaYaka people in Congo and the extensive research of anthropologists studying other hunter-gatherer societies, Dr Chaudhary highlights major differences in the ways in which hunter-gatherer children are cared for compared to their peers in developed countries. He stresses that "contemporary hunter-gatherers must not be thought of as 'living fossils', and while their ways of life may offer some clues about our prehistory, they are still very much modern populations each with a unique cultural and demographic history."

Physical contact and attentiveness


Despite increasing uptake of baby carriers and baby massage in developed countries, levels of physical contact with infants remain far higher in hunter-gatherer societies. In Botswana, for instance, 10-20 week old !Kung infants are in physical contact with someone for around 90% of daylight hours, and almost 100% of crying bouts are responded to, almost always with comforting or nursing -- scolding is extremely rare.

The study points out that this exceptionally attentive childcare is made possible because of the major role played by non-parental caregivers, or 'alloparents', which is far rarer in developed countries.

Non-parental caregivers

In many hunter-gatherer societies, alloparents provide almost half of a child's care. A previous study found that in the DRC, Efe infants have 14 alloparents a day by the time they are 18 weeks old, and are passed between caregivers eight times an hour.

Dr Chaudhary said: "Parents now have much less childcare support from their familial and social networks than would likely have been the case during most of our evolutionary history. Such differences seem likely to create the kind of evolutionary mismatches that could be harmful to both caregivers and children."

"The availability of other caregivers can reduce the negative impacts of stress within the nuclear family, and the risk of maternal depression, which has knock-on effects for child wellbeing and cognitive development."

The study emphasises that alloparenting is a core human adaptation, contradicting 'intensive mothering' narratives which emphasise that mothers should use their maternal instincts to manage childcare alone. Dr Chaudhary and Dr Swanepoel write that 'such narratives can lead to maternal exhaustion and have dangerous consequences'.

Care-giving ratios

The study points out that communal living in hunter-gatherer societies results in a very high ratio of available caregivers to infants/toddlers, which can even exceed 10:1.

This contrasts starkly with the nuclear family unit, and even more so with nursery settings, in developed countries. According to the UK's Department of Education regulations, nurseries require ratios of 1 carer to 3 children aged under 2 years, or 1 carer to 4 children aged 2-3.

Dr Chaudhary said: "Almost all day, hunter-gatherer infants and toddlers have a capable caregiver within a couple of metres of them. From the infant's perspective, that proximity and responsiveness, is very different from what is experienced in many nursery settings in the UK."

"If that ratio is stretched even thinner, we need to consider the possibility that this could have impacts on children's wellbeing."

Children providing care and mixed-age active learning

In hunter-gatherer societies, children play a significantly bigger role in providing care to infants and toddlers than is the case in developed countries. In some communities they begin providing some childcare from the age of four and are capable of sensitive caregiving; and it is common to see older, but still pre-adolescent children looking after infants.

By contrast, the NSPCC in the UK recommends that when leaving pre-adolescent children at home, babysitters should be in their late teens at least.

Dr Chaudhary said: "In developed countries, children are busy with schooling and may have less opportunity to develop caregiving competence. However, we should at least explore the possibility that older siblings could play a greater role in supporting their parents, which might also enhance their own social development."

The study also points out that instructive teaching is rare in hunter-gatherer societies and that infants primarily learn via observation and imitation. From around the age of two, hunter-gatherer children spend large portions of the day in mixed-age (2-16) 'playgroups' without adult supervision. There, they learn from one another, acquiring skills and knowledge collaboratively via highly active play practice and exploration.

Learning and play are two sides of the same coin, which contrasts with the lesson-time / play-time dichotomy of schooling in the UK and other developed countries.

Dr Chaudhary and Dr Swanepoel note that "Classroom schooling is often at odds with the modes of learning typical of human evolutionary history." The study acknowledges that children living in hunter-gather societies live in very different environments and circumstances than those in developed countries:

"Foraging skills are very different to those required to make a living in market-economies, and classroom teaching is certainly necessary to learn the latter. But children may possess certain psychological learning adaptations that can be practically harnessed in some aspects of their schooling. When peer and active learning can be incorporated, they have been shown to improve motivation and performance, and reduce stress." The authors also highlight that physical activity interventions have been shown to aid performance among students diagnosed with ADHD.

The study calls for more research into children's mental health in hunter-gatherer societies to test whether the hypothesised evolutionary mismatches actually exist. If they do, such insights could then be used to direct experimental intervention trials in developed countries.

Read more at Science Daily

Mar 1, 2023

Ice Age survivors

The team analysed the genomes of 356 prehistoric hunter gatherers from different archaeological cultures -- including new data sets of 116 individuals from 14 different European and Central Asian countries. Modern humans began to spread across Eurasia around 45,000 years ago but previous research showed that the first modern humans that arrived in Europe did not contribute to later populations. This study focuses on the people who lived between 35,000 and 5,000 years ago and that are, at least partially, the ancestors of the present-day population of Western Eurasia, including -- for the first time -- the genomes of people who lived during the Last Glacial Maximum (LGM), the coldest phase of the last Ice Age, around 25,000 years ago.

Climatic refugium or dead end?

Surprisingly, the research team found that populations from different regions associated with the Gravettian culture, which was widespread across the European continent between 32,000 and 24,000 years ago, were not closely related to each other. They were linked by a common archaeological culture: they used similar weapons and produced similar portable art. Genetically, however, the populations from western and southwestern Europe (today's France and Iberia) differed from contemporaneous populations from central and southern Europe (today's Czech Republic and Italy).

Furthermore, the gene pool of the western Gravettian populations is found continuously for at least 20,000 years: their descendants who are associated with the Solutrean and Magdalenian cultures stayed in southwestern Europe during the coldest period of the last Ice Age (between 25,000 and 19,000 years ago) and later spread north-eastward to the rest of Europe. "With these findings, we can for the first time directly support the hypothesis that during the Last Glacial Maximum people found refuge in the climatically more favourable region of southwestern Europe" says first author Cosimo Posth.

The Italian peninsula was previously considered to be another climatic refugium for humans during the LGM. However, the research team found no evidence for this, on the contrary: hunter-gatherer populations associated with the Gravettian culture and living in central and southern Europe are no longer genetically detectable after the LGM. People with a new gene pool settled in these areas, instead. "We find that individuals associated with a later culture, the Epigravettian, are genetically distinct from the area's previous inhabitants," says co-author He Yu. "Presumably, these people came from the Balkans, arrived first in northern Italy around the time of the glacial maximum and spread all the way south to Sicily."

Large-scale genetic replacement

The analysed genomes also show that the descendants of these Epigravettian inhabitants of the Italian peninsula spread across the rest of Europe about 14,000 years ago, replacing populations associated with the Magdalenian culture. The research team describes a large-scale genetic replacement that may have been caused, in part, by climatic changes that forced people to migrate: "At that time, the climate warmed up quickly and considerably and forests spread across the European continent. This may have prompted people from the south to expand their habitat. The previous inhabitants may have migrated to the north as their habitat, the 'mammoth' steppe, dwindled," says Johannes Krause, the study's senior author.

Furthermore, the findings show that there had been no genetic exchange between contemporaneous hunter-gatherer populations in western and eastern Europe for more than 6,000 years. Interactions between people from central and eastern Europe can only be detected again from 8,000 years ago. "At that time, hunter-gatherers with distinct ancestries and appearances started to mix with each other. They were different in many aspects, including their skin and eye colour," says He Yu.

During this time agriculture and a sedentary lifestyle spread from Anatolia to Europe. "It is possible that the migration of early farmers into Europe triggered the retreat of hunter-gatherer populations to the northern edge of Europe. At the same time, these two groups started mixing with each other, and continued to do so for around 3,000 years," Krause says.

Read more at Science Daily

Jan 24, 2023

Agriculture linked to changes in age-independent mortality in North America

The transition to agriculture from hunting and gathering in pre-colonial North America led to changes in age-independent mortality, or mortality caused by factors that are not associated with age, according to a new study by a Penn State-led research team. The team found that the intensification of crop use occurred in two phases, the first of which led to a decline in human age-independent mortality, while the second is associated with a rise in it. The study is the first to tie patterns of age-independent mortality to food production.

"This study tells the story of our shared human experience," said George Milner, distinguished professor of anthropology at Penn State and lead author. "We have several examples around the world where we see a move toward crop domestication as an independent event -- eastern North America, particularly the midcontinent, being one of them, but so too the Fertile Crescent in the Middle East. Also, there are demographic changes happening. This paper addresses the relationship between the move toward agriculture and demographic change."

The researchers examined previously published data to identify general trends in archaeobotanical samples, or the remains of plants in the archaeological record, and skeletal samples from sites across eight states stretching from Illinois to northern Alabama. They wanted to study the relationship between the domestication of crops and an index that uses skeletal data to capture the frequency of juveniles aged five to 19 years old relative to all individuals aged five or more. Anthropologists normally use the index to measure fertility rates and population growth, but the new work shows it is more responsive to age-independent mortality.

Mortality models, including those for pre-industrial societies, contain three components: juvenile mortality, which declines as children get older; adult mortality, where the probability of dying increases with advancing age; and age-independent mortality, an equal probability of dying for members of all age groups, which might occur in extreme events like food shortages, epidemics or warfare.

The researchers studied the archaeobotanical data to identify where the record showed an increase in the consumption of domesticated crops compared to foraged foods like nuts. They also examined skeletal data to identify decreases or increases in the indicator of age-independent mortality. The index focuses on individuals between five and 19 years old because in human populations that age range is characterized by low mortality relative to other age groups. Increases in mortality for this age group would indicate the occurrence of events like famines or conflict.

The researchers identified a strong correlation between crop domestication and changing age-independent mortality rates. Crop domestication happened in two stages in pre-colonial North America, with a decrease in age-independent mortality noted during the first stage of crop domestication and a rise during the second stage. The researchers reported their findings in the Proceedings of the National Academy of Sciences.

"What we've found is the index that has traditionally been interpreted as a fertility and population growth indicator is more tightly correlated to age-independent mortality, which reflects the number of deaths in the part of the age distribution where very few people die," said Milner. "This means that the pattern of first adoption of agriculture, seen elsewhere in the world and observed in eastern North America as well, coincides with lower age-independent mortality. Basically, it's good times, and that's what we see culturally."

The first stage of agricultural intensification in North America, which includes the cultivation of plants such as squash, sunflower and other native plants, occurred approximately 2,000 years ago during the Middle Woodland period up to about A.D. 500, said Milner. Indigenous societies flourished during this time. They established long-distance exchange networks, had an incredibly rich ceremonial life, and constructed big mounds and earthwork complexes.

The archaeological record shows that in the centuries just before A.D. 1000, and from that time onward, there was an increase in warfare. During this time Indigenous societies began cultivating maize and beans, and a number of new cultural changes occurred, including the initial development of powerful chiefdom societies. Age-independent mortality increased during this period, presumably due to conflict and the spread of diseases from higher numbers of individuals living near one another.

"The overall pattern seen in the demographic picture of North American pre-European contact is similar to other datasets from around the world," Milner said. "The entire story makes perfect sense in terms of agricultural productivity, demographic change and cultural developments, including change over time in conflict and sociopolitical systems."

The study links, for the first time, a worldwide pattern to age-independent mortality and agricultural developments, according to Milner.

Read more at Science Daily

Dec 29, 2022

Hunter-gatherer social ties spread pottery-making far and wide

Analysis of more than 1,200 vessels from hunter-gatherer sites has shown that pottery-making techniques spread vast distances over a short period of time through social traditions being passed on.

The team, which includes researchers from the University of York and the British Museum, analysed the remains of 1,226 pottery vessels from 156 hunter-gatherer sites across nine countries in Northern and Eastern Europe. They combined radiocarbon dating, together with data on the production and decoration of ceramic vessels, and analysis of the remains of food found inside the pots.

Their findings, published in the journal Nature Human Behaviour, suggest that pottery-making spread rapidly westwards from 5,900 BCE onwards and took only 300-400 years to advance over 3,000 km, equivalent to 250 km in a single generation.

Professor Oliver Craig, from the University of York's Department of Archaeology, said: "Our analysis of the ways pots were designed and decorated as well as new radiocarbon dates suggests that knowledge of pottery spread through a process of cultural transmission.

"By this we mean that the activity spread by the exchange of ideas between groups of hunter-gatherers living nearby, rather than through migration of people or an expanding population as we see for other key changes in human history such as the introduction of agriculture."

"That methods of pottery-making spread so far and so fast through the passing on of ideas is quite surprising. Specific knowledge may have been shared through marriages or at centres of aggregation, specific points in the landscape where groups of hunter-gatherers came together perhaps at certain times of the year."

By studying traces of organic materials left in the pots, the team demonstrated that the pottery was used for cooking, so the ideas of pottery-making may have been spread through shared culinary traditions.

Carl Heron, from the British Museum, said: "We found evidence that the vessels were used for cooking a wide range of animals, fish and plants, and this variety suggests that the drivers for making the pottery were not in response to a particular need, such as detoxifying plants or processing fish, as has previously been suggested.

"We also found patterns suggesting that pottery use was transmitted along with knowledge of their manufacture and decoration. These can be seen as culinary traditions that were rapidly transmitted with the artefacts themselves."

The world's earliest pottery containers come from East Asia and may have spread rapidly eastwards through Siberia, before being taken up by hunter-gatherer societies across Northern Europe, long before the arrival of farming.

Read more at Science Daily

Dec 6, 2022

Feline genetics help pinpoint first-ever domestication of cats

Nearly 10,000 years ago, humans settling in the Fertile Crescent, the areas of the Middle East surrounding the Tigris and Euphrates rivers, made the first switch from hunter-gatherers to farmers. They developed close bonds with the rodent-eating cats that conveniently served as ancient pest-control in society's first civilizations.

A new study at the University of Missouri found this lifestyle transition for humans was the catalyst that sparked the world's first domestication of cats, and as humans began to travel the world, they brought their new feline friends along with them.

Leslie A. Lyons, a feline geneticist and Gilbreath-McLorn endowed professor of comparative medicine in the MU College of Veterinary Medicine, collected and analyzed DNA from cats in and around the Fertile Crescent area, as well as throughout Europe, Asia and Africa, comparing nearly 200 different genetic markers.

"One of the DNA main markers we studied were microsatellites, which mutate very quickly and give us clues about recent cat populations and breed developments over the past few hundred years," Lyons said. "Another key DNA marker we examined were single nucleotide polymorphisms, which are single-based changes all throughout the genome that give us clues about their ancient history several thousands of years ago. By studying and comparing both markers, we can start to piece together the evolutionary story of cats."

Lyons added that while horses and cattle have seen various domestication events caused by humans in different parts of the world at various times, her analysis of feline genetics in the study strongly supports the theory that cats were likely first domesticated only in the Fertile Crescent before migrating with humans all over the world. After feline genes are passed down to kittens throughout generations, the genetic makeup of cats in western Europe, for example, is now far different from cats in southeast Asia, a process known as 'isolation by distance.'

"We can actually refer to cats as semi-domesticated, because if we turned them loose into the wild, they would likely still hunt vermin and be able to survive and mate on their own due to their natural behaviors," Lyons said. "Unlike dogs and other domesticated animals, we haven't really changed the behaviors of cats that much during the domestication process, so cats once again prove to be a special animal."

Lyons, who has researched feline genetics for more than 30 years, said studies like this also support her broader research goal of using cats as a biomedical model to study genetic diseases that impact both cats and people, such as polycystic kidney disease, blindness and dwarfism.

"Comparative genetics and precision medicine play key roles in the 'One Health' concept, which means anything we can do to study the causes of genetic diseases in cats or how to treat their ailments can be useful for one day treating humans with the same diseases," Lyons said. "I am building genetic tools, genetic resources that ultimately help improve cat health. When building these tools, it is important to get a representative sample and understand the genetic diversity of cats worldwide so that our genetic toolbox can be useful to help cats all over the globe, not just in one specific region."

Throughout her career, Lyons has worked with cat breeders and research collaborators to develop comprehensive feline DNA databases that the scientific community can benefit from, including cat genome sequencing from felines all around the world. In a 2021 study, Lyons and colleagues found that the cat's genomic structure is more similar to humans than nearly any other non-primate mammal.

"Our efforts have helped stop the migration and passing-down of inherited genetic diseases around the world, and one example is polycystic kidney disease, as 38% of Persian cats had this disease when we first launched our genetic test for it back in 2004," Lyons said. "Now that percentage has gone down significantly thanks to our efforts, and our overall goal is to eradicate genetic diseases from cats down the road."

Currently, the only viable treatment for polycystic kidney disease has unhealthy side effects, including liver failure. Lyons is currently working with researchers at the University of California at Santa Barbara to develop a diet-based treatment trial for those suffering from the disease.

"If those trials are successful, we might be able to have humans try it as a more natural, healthier alternative to taking a drug that may cause liver failure or other health issues," Lyons said. "Our efforts will continue to help, and it feels good to be a part of it."

Read more at Science Daily

May 12, 2022

The genetic origins of the world's first farmers clarified

The genetic origins of the first agriculturalists in the Neolithic period long seemed to lie in the Near East. A new study published in the journal Cell shows that the first farmers actually represented a mixture of Ice Age hunter-gatherer groups, spread from the Near East all the way to south-eastern Europe. Researchers from the University of Bern and the SIB Swiss Institute of Bioinformatics as well as from the Johannes Gutenberg University Mainz and the University of Fribourg were involved in the study. The method they developed could help reveal other human evolution patterns with unmatched resolution.

The first signs of agriculture and a sedentary lifestyle are found in the so-called 'Fertile Crescent', a region in the Near East where people began to settle down and domesticate animals and plants about 11,000 years ago. The question of the origin of agriculture and sedentism has occupied researchers for over 100 years: did farming spread from the Near East through cultural diffusion or through migration? Genetic analyses of prehistoric skeletons so far supported the idea that Europe's first farmers were descended from hunter-gatherer populations in Anatolia. While that may well be the case, this new study shows that the Neolithic genetic origins cannot clearly be attributed to a single region. Unexpected and complex population dynamics occurred at the end of the Ice Age, and led to the ancestral genetic makeup of the populations who invented agriculture and a sedentary life-style i.e. the first Neolithic farmers.

First farmers emerged from a mixing process starting 14,000 years ago

Previous analyses had suggested that the first Neolithic people were genetically different from other human groups from that time. Little was known about their origins. Nina Marchi, one of the study's first authors from the Institute of Ecology and Evolution at the University of Bern and SIB says: "We now find that the first farmers of Anatolia and Europe emerged from a population admixed between hunter-gatherers from Europe and the Near East." According to the authors, the mixing process started around 14,000 years ago, which was followed by a period of extreme genetic differentiation lasting several thousand years.

A novel approach to model population history from prehistoric skeletons

This research was made possible by combining two techniques: the production of high-quality ancient genomes from prehistoric skeletons, coupled with demographic modeling on the resulting data. The research team coined the term "demogenomic modeling" for this purpose. "It is necessary to have genome data of the best possible quality so that the latest statistical genomic methods can reconstruct the subtle demographic processes of the last 30 thousand years at high resolution," says Laurent Excoffier, one of the senior authors of the study. Laurent Excoffier is a professor at the Institute of Ecology and Evolution at the University of Bern and group leader at SIB. He initiated the project together with Joachim Burger of the Johannes Gutenberg University in Mainz and Daniel Wegmann of the University of Fribourg. Nina Marchi adds: "Simply comparing the similarity of different ancient genomes is not enough to understand how they evolved. We had to reconstruct the actual histories of the populations studied as accurately as possible. This is only possible with complex population genetic statistics."

Interdisciplinarity key to solve such ancient puzzles

Joachim Burger of the University of Mainz and second senior author emphasizes the necessity of interdisciplinarity: "It took close to ten years to gather and analyze the skeletons suitable for such a study. This was only possible by collaborating with numerous archaeologists and anthropologists, who helped us to anchor our models historically." The historical contextualisation was coordinated by Maxime Brami, who works with Burger at Johannes Gutenberg University. The young prehistorian was surprised by some of the study's findings: "Europe's first farmers seem to be descended from hunter-gatherer populations that lived all the way from the Near East to the Balkans. This was not foreseeable archaeologically."

Towards a general model of human population evolution

Genetic data from fossils (skeletons) are badly damaged and must be processed accordingly using bioinformatics, as Daniel Wegmann from the University of Fribourg and group leader at SIB explains: "The high-resolution reconstruction of the prehistory of the Europeans was only possible thanks to methods that we specifically developed to analyse ancient fossil genomes." Joachim Burger adds: "With these approaches, we have not only elucidated the origins of the world's first Neolithic populations, but we have established a general model of the evolution of human populations in Southwest Asia and Europe."

Read more at Science Daily

Apr 25, 2022

Friendship ornaments from the Stone Age

Roughly 6,000 years ago, hunter-gatherer communities in northeast Europe produced skillfully manufactured slate ring ornaments in great numbers. While these ornaments are commonly referred to as 'slate rings', they were rarely used as intact rings. Instead, the ornaments were fragmented on purpose, using pieces of rings as tokens. These fragments were further processed into pendants.

The fragments have most likely served as symbols of the social relations of Stone Age hunter-gatherers.

Purposeful fragmentation of ornaments

As most archaeological material is found in a fragmented state, the phenomenon has been considered a natural consequence of objects' having been long buried underground. However, according to Postdoctoral Researcher Marja Ahola from the University of Helsinki, not all objects have necessarily been broken by accident. Instead, it is possible some were fragmented on purpose as part of maintaining social relations, bartering or ritual activities. The research now completed has demonstrated that a substantial number of ornaments have been found in extensive and central locations. As some of the ornaments originate in Lake Onega region and have been transported to Finland through a widespread exchange network, it is possible that they symbolise the connections established within the network.

By matching pieces of slate ring ornaments, analysing their geochemical composition and investigating traces of use and manufacture in the objects, a research group at the University of Helsinki and the University of Turku demonstrated that the ornaments had not only been worn, but also intentionally broken. Because fragments from the same ornament were found in two different locations, it is possible that they were worn by two different individuals. Another indication of this is the fact that one of the fragments had been worked on more finely than the other.

"These fragments of the same object may show the handprint and preferences of two individuals. Perhaps they wore the ornaments as a symbol of a connection established," Ahola muses.

A similar link was found in slate ring ornaments created during the same manufacturing process, one of which was found in a settlement-site context and the other in a burial site investigated near the settlement.

"What we see here may be one way of maintaining connection between the living and the dead. This is also the first clear material connection between a certain place of residence and a burial site. In other words, the people who lived there most likely buried their dead in a site close to them," Ahola explains.

An X-ray fluorescence analysis (XRF) of a little over 50 slate ring ornaments demonstrated that some of the ornaments or fragments thereof had been imported from Lake Onega region, Russia, hundreds of kilometres from the site where they were found. XRF analyses can be used to determine the element concentrations and raw materials of inorganic archaeological materials with a very high precision. The technique can be applied as an entirely non-invasive surface analysis, which makes it perfectly suited to the study of archaeological objects.

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Mar 6, 2022

Mummification in Europe may be older than previously known

Mummification of the dead probably was more common in prehistory than previously known. This discovery is made at the hunter-gatherer burial sites in the Sado Valley in Portugal, dating to 8,000 years ago. A new study, headed by archaeologists at Uppsala University and Linnaeus University in Sweden and University of Lisbon in Portugal, presents new evidence for pre-burial treatments such as desiccation through mummification, which has not been suggested for the European Mesolithic before. The results are now published in European Journal of Archaeology.

Until now, the oldest cases of intentional mummification were known from the Chinchorro hunter-gatherers living in the coastal region of the Atacama Desert in northern Chile with examples of mummified bodies buried in shell middens around 7,000 years ago still preserving soft tissue. However, most surviving mummies worldwide are more recent, dating between a few hundred years and 4,000 years old.

Mummification in prehistory is a challenging topic for researchers because it is difficult to detect if a body was preserved through mummification when soft tissue is no longer visible. An additional difficulty is the lack of written reports for these early periods. Unlike bone, finding soft tissue in archaeological sites is rare due to issues of preservation, and without it, it is difficult to recognize if the remains have been curated soon after death. This is particularly challenging in temperate and wetter climates, such as in most of Europe, where soft tissues and fabrics do not normally survive in archaeological sites.

Using recently discovered photographs of the skeletal remains of thirteen individuals excavated in the 1960s in the Sado Valley Mesolithic shell middens in Portugal, the researchers were able to reconstruct the positions in which the bodies were buried providing a unique opportunity to learn more about mortuary rituals taking place 8,000 years ago.

The study combined the approach of archaeothanatology with human decomposition experiments. Archaeothanatology is an approach used by archaeologists to document and analyse human remains in archaeological sites that combines observations of the spatial distribution of the bones in the grave with knowledge about how the human body decomposes after death. Archaeologists can then reconstruct how the dead body was handled after death and buried, even if several millennia have passed. In this study, the archaeothanatology was also informed by results from human decomposition experiments on mummification and burial at the Forensic Anthropology Research Facility at Texas State University.

Based on the results from the experiments, an observable signature for a mummy could be proposed that combines several observations: a hyperflexion of the limbs, an absence of disarticulation in significant parts of the skeleton, and a rapid infilling of sediment around the bones. These were all clearly present in at least one of the burials in this study. The analysis showed that some bodies were buried in extremely flexed positions with the legs flexed at the knees and placed in front of the chest.

During decomposition, the bones usually become disarticulated at weak joints, such as at the feet, but in these cases, the articulations were maintained. The researchers propose that this pattern of hyperflexion and lack of disarticulation could be explained if the body was not placed in the grave as a fresh cadaver, but in a desiccated state as a mummied corpse. Desiccation not only maintains some of these otherwise weak articulations, but also allows for a strong flexion of the body since the range of movement increases when the volume of soft tissue is smaller. Because the bodies were desiccated before burial, there is very little or no sediment present between the bones and the articulations are maintained by the continuous infilling of the surrounding soil supporting the bones and preventing the collapse of the articulations.

The researchers suggest that the observed patterns could be the product of a guided natural mummification process. The manipulation of the body during mummification would have taken place over an extended period of time, during which the body gradually would become desiccated to maintain its bodily integrity, and simultaneously contracted by trussing with rope or bandages to compress it into a desired position. When the process was finished, the body would have been easier to transport (being more contracted and significantly lighter than the fresh cadaver) while ensuring that it was buried while retaining its appearance and anatomical integrity.

Read more at Science Daily

Nov 9, 2021

Diet restricted size of hunter-gatherer societies

Short growing seasons limited the possible size of hunter-gatherer societies by forcing people to rely on meat, according to a recent study by a team of international reseachers including McGill University professor Eric Galbraith.

After looking at population size for the roughly 300 hunter-gatherer societies which existed until quite recently, the researchers found that many of these groups were much smaller than might have been expected from the local ecosystem productivity. In regions with short growing seasons, hunter-gatherer groups had smaller populations per square kilometre than groups who depended on abundant plant foods throughout the year.

Need for meat limited population size

"Basically, if people had to live through long dry or cold seasons when plant food was scarce, in order to survive they had to depend on hunting a very limited number of animals," explains Galbraith, a professor in McGill's Department of Earth and Planetary Sciences and at the ICTA-UAB (Institut de Ciència i Tecnologia Ambientals of the Autonomous University of Barcelona), and a senior author on the paper published recently in the journal Nature Ecology & Evolution.

"This led to a seasonal bottleneck in the amount of food available, which then set the overall limit on the population size, no matter how much food there was during the plentiful times."

The team developed a mathematical model that simulates daily human foraging activities (gathering and hunting) and the resultant carbon (energy) flows between vegetation, animals, and hunter-gatherers in a realistic global environment.

"We were struck by the fact that -- despite a long list of unknowns -- a very strong result emerged from the model equations," says Galbraith. "Wherever growing seasons were short, hunter gatherers required meat to make up a high percentage of their diets. And -- just as in the modern world -- it took much more land to produce the same amount of meat as plant-based food."

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Sep 15, 2021

Prehistoric humans rarely mated with their cousins

The researchers re-analyzed previously published DNA data from ancient humans that lived during the last 45,000 years to find out how closely related their parents were. The results surprising: Ancient humans rarely chose their cousins as mates. In a global dataset of 1,785 individuals only 54, that is, about three percent, show the typical signs of their parents being cousins. Those 54 did not cluster in space or time, showing that cousin matings were sporadic events in the studied ancient populations. Notably, even for hunter-gatherers who lived more than 10,000 years ago, unions between cousins were the exception.

To analyze such a large dataset, the researchers developed a new computational tool to screen ancient DNA for parental relatedness. It detects long stretches of DNA that are identical in the two DNA copies, one inherited from the mother and one from the father. The closer the parents are related, the longer and more abundant such identical segments are. For modern DNA data, computational methods can identify these stretches with ease. However, the quality of DNA from bones that are thousands of years old is, in most cases, too low to apply these methods. Thus, the new method fills the gaps in the ancient genomes by leveraging modern high-quality DNA data. "By applying this new technique we could screen more than ten times as many ancient genomes than previously possible," says Harald Ringbauer from MPI-EVA, the lead researcher of the study.

Beyond identifying matings of close kin, the new method also allowed the researchers to study background relatedness. Such relatedness originates from the typically many unknown distant relationships within small populations. As a key result, the researchers found a substantial demographic impact of the technological innovation of agriculture. This was always followed by a marked decay in background parental relatedness, indicative of increasing population sizes. By analyzing time transects of more than a dozen geographic regions across the globe, the researchers expanded upon previous evidence that population sizes increased in societies practicing farming compared to hunter-gatherer subsistence strategies.

The new method to screen ancient DNA for parental relatedness gives researchers a versatile new tool. Looking forward, the field of ancient DNA is quickly developing, with more and more ancient genomes being produced every year. By elucidating mating choices as well as the dynamics of past population sizes, the new method will allow researchers to shed more light on the lives of our ancestors.

From Science Daily

Sep 3, 2021

New evidence supports idea that America’s first civilization was made up of ‘sophisticated’ engineers

The Native Americans who occupied the area known as Poverty Point in northern Louisiana more than 3,000 years ago long have been believed to be simple hunters and gatherers. But new Washington University in St. Louis archaeological findings paint a drastically different picture of America's first civilization.

Far from the simplicity of life sometimes portrayed in anthropology books, these early Indigenous people were highly skilled engineers capable of building massive earthen structures in a matter of months -- possibly even weeks -- that withstood the test of times, the findings show.

"We as a research community -- and population as a whole -- have undervalued native people and their ability to do this work and to do it quickly in the ways they did," said Tristram R. "T.R." Kidder, lead author and the Edward S. and Tedi Macias Professor of Anthropology in Arts & Sciences.

"One of the most remarkable things is that these earthworks have held together for more than 3,000 years with no failure or major erosion. By comparison, modern bridges, highways and dams fail with amazing regularity because building things out of dirt is more complicated than you would think. They really were incredible engineers with very sophisticated technical knowledge."

The findings were published in Southeastern Archaeology on September, 1, 2021. Washington University's Kai Su, Seth B. Grooms, along with graduates Edward R. Henry (Colorado State) and Kelly Ervin (USDA Natural Resources Conservation Service) also contributed to the paper.

The Poverty Point World Heritage site consists of a massive 72-foot-tall earthen mound and concentric half circle ridges. The structures were constructed by hunter-gatherers approximately 3,400 years ago from nearly 2 million cubic yards of soil. Amazingly, this was done without the luxury of modern tools, domesticated animals or even wheeled carts.

According to Kidder, the site was likely an important religious site where Native Americans came in pilgrimage, similar to Mecca. It was abandoned abruptly between 3,000-3,200 years ago -- most likely due to documented flooding in the Mississippi Valley and climate change.

The ridges at Poverty Point contain vast amounts of artifacts around the edges and within, suggesting that people lived there. Kidder and team re-excavated and re-evaluated a site on Ridge West 3 at the Poverty Point Site that was originally excavated by renowned archaeologist Jon Gibson in 1991.

Using modern research methods including radiocarbon dating, microscopic analysis of soils and magnetic measurements of soils, the research provides conclusive evidence that the earthworks were built rapidly. Essentially, there is no evidence of boundaries or signs of weathering between the various levels, which would have occurred if there was even a brief pause in construction. Kidder believes the construction was completed in lifts, or layers of sediment deposited to increase the ridge height and linear dimensions before another layer was placed to expand the footprint vertically and horizontally.

Why does that matter? According to Kidder, the findings challenge previous beliefs about how pre-modern hunters and gatherers behaved. Building the enormous mounds and ridges at Poverty Point would have required a large labor pool that was well organized and would have required leadership to execute. Hunters and gathers were believed to shun politics.

"Between the speed of the excavation and construction, and the quantity of earth being moved, these data show us native people coming to the site and working in concert. This in and of itself is remarkable because hunter-gatherers aren't supposed to be able to do these activities," Kidder said.

What's even more impressive than how quickly the people built the earthen structures is the fact that they're still intact. Due to its proximity to the Gulf of Mexico, this area receives immense amounts of rain that makes earthworks especially prone to erosion. Microscopic analysis of soils shows that the Native Americans mixed different types of soil -- clays, silts and sand -- in a calculated recipe to make the structures stronger.

Read more at Science Daily

Jan 31, 2021

Gendered division of labor shaped human spatial behavior

 Navigating, exploring and thinking about space are part of daily life, whether it's carving a path through a crowd, hiking a backcountry trail or maneuvering into a parking spot.

For most of human history, the driving force for day-to-day wayfinding and movement across the landscape was a need for food. And unlike other primates, our species has consistently divided this labor along gender lines.

In new research published in Nature Human Behaviour, scientists including James Holland Jones of Stanford and lead author Brian Wood of University of California, Los Angeles, argue that the increasingly gendered division of labor in human societies during the past 2.5 million years dramatically shaped how our species uses space, and possibly how we think about it.

Underlying these conclusions is a huge and detailed trove of travel data revealing stark differences in the ways men and women among the nomadic Hadza people of Tanzania use space. A contemporary hunter-gatherer society, the Hadza provide a window into a highly mobile lifestyle, which was the norm for our species before the widespread adoption of agriculture.

"We're taking gender differences as a given in this particular cultural setting, and then asking what consequences they have downstream," said Jones, an associate professor of Earth system science at Stanford's School of Earth, Energy & Environmental Sciences (Stanford Earth) and a senior fellow at Stanford Woods Institute for the Environment.

A better understanding of this dynamic could yield clues about why men and women seem to think about space differently. Research in many human populations suggests men and women are better at different types of spatial tasks. On average, women tend to excel on spatial memory tasks, while men tend to score higher on two basic measures of spatial cognition associated with movement: mental rotation of objects and accurately pointing to distant locations.

'Male work is more navigationally challenging'

The paper examines a popular theory that men's hunting for wild game would produce more extensive and sinuous travel, and that women's harvesting of plant foods would lead to more concentrated, straight-line travel to and from known locations.

While previous efforts to substantiate the theory have relied heavily on verbal accounts, the researchers here tested it by examining more than 13,000 miles of travel logged on lightweight GPS trackers worn by Hadza foragers between 2005 and 2018. "One or two researchers would walk through camp early in the morning as people were rousing," the authors write. "We would greet people at their homes or hearths and hand out GPS devices to be worn during the day."

Around nightfall, when most people had returned to camp, Wood and assistants hired in the Hadza community removed the devices. They ultimately used data from 179 people, representing 15 camps and ranging in age from two to 84 years old.

The authors also examined the degree of overlap in the lands visited by men and women. "One of the most surprising results of this study was the fact that Hadza men and women essentially occupy different worlds from a young age. In our data, most of the landscape was effectively gender-segregated," said Wood, an assistant professor of anthropology at UCLA who began working on this paper a decade ago as a postdoctoral scholar at Stanford.

To analyze the movement data, the researchers adopted techniques from the field of movement ecology and also developed custom software. As expected, the results show men walked further per day, covered more land in less direct paths and were more likely to travel alone. "In this hunting and gathering context, male work is more navigationally challenging," the researchers write.

Although some individual day journeys extended to 20 miles or more, Hadza men overall averaged eight miles per day and women -- many of them accompanied by young children -- averaged nearly five miles. Gender differences emerged by the age of six. From the mid-forties, the gender difference declined, mostly due to decreasing travel by men while women sustained more of their daily mileage.

Human mobility in a changing world

Detailed spatial data like those amassed in this study will aid future comparative research into human mobility, according to the authors. This holds particular resonance in light of a pandemic that has forced sudden revisions of normal movement patterns and heightened attention to the costs and benefits of different spatial habits.

Already, Wood has begun to apply technical, logistical and scientific lessons from this study to a new National Science Foundation project meant to help identify research and policy priorities to prepare the U.S. for inevitable future pandemics -- in part by measuring mobility and modeling patterns of social interaction. "The study of human movement can be used to identify at-risk communities for disease transmission and spread," Wood explained.

Even when we're not in a pandemic, Jones said, people's mobility drives economic activity, social cohesion and environmental impacts. And the environment, in turn, shapes spatial behavior. That feedback loop is at the heart of some of the internal migration patterns already emerging as a response to global warming. As once-rare weather events become commonplace, Jones explained, migrant laborers will likely travel longer distances for work; more people will engage in seasonal migration to pursue agricultural work or escape hurricanes and droughts, and crop failures will drive more rural residents to urban areas.

"Changing mobility is going to be one of the key ways that humans adapt to a heated world," Jones said. "Knowing more about gender differences and other drivers for spatial behaviors across a wide swath of human populations and ecological contexts will help us anticipate how this adaptation will play out and inform policies to manage it."

Read more at Science Daily

Nov 5, 2020

Early big-game hunters of the Americas were female, researchers suggest

 

Vicunas in Peru highlands.
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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Sep 8, 2020

Ancient hunters stayed in frozen Northern Europe rather than migrating to warmer areas, evidence from Arctic fox bones shows

 Ancient hunters stayed in the coldest part of Northern Europe rather than migrating to escape freezing winter conditions, archaeologists have found.

Evidence from Arctic fox bones show communities living around 27,500 years ago were killing small prey in the inhospitable North European Plains during the winter months of the last Ice Age.

Researchers have found no evidence of dwellings, suggesting people only stayed for a short time or lived in tents in the area excavated, Kraków Spadzista in Southern Poland -- one of the largest Upper Palaeolithic sites in Central Europe. Until now it wasn't clear if people retreated elsewhere each winter to avoid the intense cold.

Dr Alexander Pryor, from the University of Exeter, who led the study, said: "Our research shows the cold harsh winter climates of the last ice age were no barrier to human activity in the area. Hunters made very specific choices about where and when to kill their prey."

Inhabitants of Kraków Spadzista around 27,500 years ago killed and butchered large numbers of woolly mammoths and arctic foxes at the site. For the first time, the research team were able to reconstruct details of how the foxes were moving around in the landscape before they died, and also what time of the year they died, through analysing the internal chemistry and growth structures of their tooth enamel and roots.

The analysis of teeth from four of the 29 hunted foxes show each was born and grew up in a different location, and had migrated either tens or hundreds of kilometres to the region before being killed by hunters -- by snares, deadfalls or other trapping methods -- for both their thick warm furs as well as meat and fat for food. The carcasses were brought back to the site to be skinned and butchered.

Analysis of the dental cementum of at least 10 fox individuals demonstrate that the majority were killed between late winter and late spring, most likely in late winter. The foxes ranged in age, from sub-adult to very old.

The study, published in the Journal of Archaeological Science: Reports, also involved Sylwia Pospuła, Piotr Wojtal, Nina Kowalik and Jarosław Wilczyński from the Polish Academy of Sciences and Tereza Nesnídalová from the University of Exeter.

Around 2,400 arctic fox bones were found about 30m south of a huge concentration of bones from more than 100 individual woolly mammoths that dominate the site, in an area used for the production of lithic tools and the processing of smaller prey animals.

The study suggests the Arctic fox colonised the area because they moved over long distances season by season, something they still do today, in order to find food.

Dr Pryor said: "Arctic fox provided both food and hides to Palaeolithic hunters, with their fur coats reaching full length around the beginning of December; this winter fur usually begins shedding by early spring. They also lay down substantial stores of body fats seasonally that are greatest from late autumn throughout the winter season and do not start to become seriously depleted until early spring. Hunters most likely targeted the foxes in the late winter period -- before the onset of fur shedding and loss of critical fat supplies.

"The high numbers of fox remains found at the site suggests what was happening was a deliberate, organised procurement strategy rather than just simple incidental hunting."

The analysis of teeth suggests hunters engaged in large-scale winter hunting of solitary Arctic foxes that were ranging widely across the landscape. The site was used as a base camp for ranging visits to maintain trapping lines and for processing hides.

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