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

Geneticists’ new research on ancient Britain contains insights on language, ancestry, kinship, milk

New research revealing a major migration to the island of Great Britain offers fresh insights into the languages spoken at the time, the ancestry of present-day England and Wales, and even ancient habits of dairy consumption.

The findings are described in Nature by a team of more than 200 international researchers led by Harvard geneticists David Reich and Nick Patterson. Michael Isakov, a Harvard undergraduate who discovered the existence of the 3,000-year-old migration, is one of the co-first authors.

The analysis is one of two Reich-led studies of DNA data from ancient Britain that Nature published on Tuesday. Both highlight technological advances in large-scale genomics and open new windows into the lives of ancient people.

"This shows the power of large-scale genetic data in concert with archaeological and other data to get rich information about our past from a time before writing," said Reich, a professor in the Department of Human Evolutionary Biology and a professor of genetics at Harvard Medical School. "The studies are not only important for Great Britain, where we now have far more ancient DNA data than in any other region, but also because of what they show about the promise of similar studies elsewhere in the world."

The researchers analyzed the DNA of 793 newly reported individuals in the largest genome-wide study involving ancient humans. Their findings reveal a large-scale migration likely from somewhere in France to the southern part of Great Britain, or modern-day England and Wales, that eventually replaced about 50 percent of the ancestry of the island during the Late Bronze Age (1200 to 800 B.C.).

The study supports a recent theory that early Celtic languages came to Great Britain from France during the Late Bronze Age. It challenges two prominent theories: that the languages arrived hundreds of years later, in the Iron Age, or 1,500 years earlier at the dawn of the Bronze Age.

Previous research has shown that large-scale movement often accompanied language changes in pre-state societies. The Reich team argues that this untold migration event makes more sense for the spread of early Celtic languages into Britain.

"By using genetic data to document times when there were large-scale movements of people into a region, we can identify plausible times for a language shift," Reich said. "Known Celtic languages are too similar in their vocabularies to plausibly descend from a common ancestor 4,500 years ago, which is the time of the earlier pulse of large-scale migration, and very little migration occurred in the Iron Age. If you're a serious scholar, the genetic data should make you adjust your beliefs: downweighting the scenario of early Celtic language coming in the Iron Age [and early Bronze Age] and upweighting the Late Bronze Age."

As part of the genetic analysis, the researchers found that the ability to digest cow's milk dramatically increased in Britain from 1200 to 200 B.C., which is about a millennium earlier than it did in central Europe. These findings illuminate a different role for dairy consumption in Britain during this period compared with the rest of mainland Europe. More study is needed to define that role, the researchers said. Increased milk tolerance would have provided a big advantage in the former of higher survival rates among the children of people carrying this genetic adaptation.

The newly discovered ancestry change happened around 3,000 years ago, more than a millennium and a half before the Saxon period. The team was aware of a migration into England at some point during this gap because of an observation they made in research published in 2016. That study showed that contemporary English people have more DNA from early European farmers than people who lived in England about 4,000 years ago. The team set out to collect DNA from later periods to detect the shift.

The discontinuity -- a specific point in time when the percentage of farmer ancestry in English genomes changed -- was first noticed in the summer of 2019 by Isakov, an applied mathematics concentrator. He had started working as a researcher in Reich's lab the summer after his first year and was able to increase the statistical power of the group's ancestry tests. When he noticed some outliers in the data from people living 3,000 years ago, he led a closer analysis and discovered the migration.

"It's an extraordinary outcome and I'm very happy that I was able to get through it," said Isakov, who will graduate in May.

The second paper looks at kinship practices of 35 individuals who lived about 5,700 years ago and were buried in a tomb at Hazleton North in Gloucestershire, England. The researchers found a 27-person family -- three times larger than the second-largest documented ancient family -- whose kin relationships could be precisely determined by analyzing their DNA. The team created a family tree that covered five generations and found examples of polygyny, polyandry, adoption, and a key role for both patrilineal and matrilineal descent.

The lab's research illustrates the interdisciplinary collaborations that are required to tell the richest stories of the ancient past, Isakov said.

"It's sort of incredible that we have geneticists, we have statisticians, we have archaeologists, linguists, and even chemical analysis coming together. I think that the fact that we're able to like merge all these fields and have an actual insight that's culturally important is a great example of interdisciplinary science."

Read more at Science Daily

Unexpected insights into early dinosaur's brain, eating habits and agility

 A pioneering reconstruction of the brain belonging to one of the earliest dinosaurs to roam the Earth has shed new light on its possible diet and ability to move fast.

Research, led by the University of Bristol, used advanced imaging and 3-D modelling techniques to digitally rebuild the brain of Thecodontosaurus, better known as the Bristol dinosaur due to its origins in the UK city. The palaeontologists found Thecodontosaurus may have eaten meat, unlike its giant long-necked later relatives including Diplodocus and Brontosaurus, which only fed on plants.

Antonio Ballell, lead author of the study published today in Zoological Journal of the Linnean Society, said: "Our analysis of Thecodontosaurus' brain uncovered many fascinating features, some of which were quite surprising. Whereas its later relatives moved around ponderously on all fours, our findings suggest this species may have walked on two legs and been occasionally carnivorous."

Thecodontosaurus lived in the late Triassic age some 205 million years ago and was the size of a large dog. Although its fossils were discovered in the 1800s, many of which are carefully preserved at the University of Bristol, scientists have only very recently been able to deploy imaging software to extract new information without destroying them. 3-D models were generated from CT scans by digitally extracting the bone from the rock, identifying anatomical details about its brain and inner ear previously unseen in the fossil.

"Even though the actual brain is long gone, the software allows us to recreate brain and inner ear shape via the dimensions of the cavities left behind. The braincase of Thecodontosaurus is beautifully preserved so we compared it to other dinosaurs, identifying common features and some that are specific to Thecodontosaurus," Antonio said. "Its brain cast even showed the detail of the floccular lobes, located at the back of the brain, which are important for balance. Their large size indicate it was bipedal. This structure is also associated with the control of balance and eye and neck movements, suggesting Thecodontosaurus was relatively agile and could keep a stable gaze while moving fast."

Although Thecodontosaurus is known for being relatively small and agile, its diet has been debated.

Antonio, a PhD student at the University of Bristol's School of Earth Sciences, said: "Our analysis showed parts of the brain associated with keeping the head stable and eyes and gaze steady during movement were well-developed. This could also mean Thecodontosaurus could occasionally catch prey, although its tooth morphology suggests plants were the main component of its diet. It's possible it adopted omnivorous habits."

The researchers were also able to reconstruct the inner ears, allowing them estimate how well it could hear compared to other dinosaurs. Its hearing frequency was relatively high, pointing towards some sort of social complexity -- an ability to recognise varied squeaks and honks from different animals.

Professor Mike Benton, study co-author, said: "It's great to see how new technologies are allowing us to find out even more about how this little dinosaur lived more than 200 million years ago.

Read more at Science Daily