UK had at least two genetically distinct human groups at end of last ice age, DNA reveals | Anthropology

Britain was home to at least two genetically distinct groups of humans at the end of the last ice age, the oldest human DNA from the UK has revealed.

About 19,000 years ago, ice sheets that had covered much of Britain were melting and the landscape once again became habitable to humans. Evidence of their return dates back to about 15,500 years ago. These early groups crossed now submerged land that once connected Britain to mainland Europe.

Human remains from the late ice age have been found at only a handful of sites in Britain, including at Gough’s Cave in Somerset and Kendrick’s Cave in Llandudno, Wales. The former is famous for having been home to “Cheddar Man” – an individual who lived about 10,000 years ago – as well as older remains that showed signs of cannibalism.

Now researchers have extracted and analysed DNA from two individuals found at these sites – the oldest DNA from Britain.

“We can see that there are two different genetic ancestry present in Britain during this late glacial period, which is perhaps not what we expected to find,” said Dr Sophy Charlton, the first author of the study from the University of York.

Writing in the journal Nature Ecology & Evolution, Charlton and colleagues report how they carried out an isotope analysis on the remains, allowing them to unpick the contribution of different food sources to their diet, and hence refine their radiocarbon dating.

An engraved human bone from Gough’s Cave
An engraved human bone from Gough’s Cave, Somerset. Photograph: Natural History Museum

Supporting previous work, the team found that the Gough’s Cave individual mainly relied on terrestrial animals, such as horses, while the diet of the Kendrick’s Cave individual included marine creatures.

The researchers then analysed nuclear and mitochondrial DNA from the two individuals. The results reveal that the remains from Gough’s Cave are from a female who lived about 14,900 years ago. This female, who was cannibalised, shared ancestry with an individual discovered in a cave in Belgium, known as Goyet Q2, who lived 15,000 years ago.

This ancestry, linked to groups that expanded from south-west Europe, has been associated with particular types of stone tools, treatment of the dead, cave art and other practices that have been labelled Magdalenian culture. Indeed, Magdalenian-style artefacts were found at Gough’s Cave.

However, despite Kendrick’s Cave containing a Magdalenian-style stone tool and a cut bovid bone from the time of the Gough Cave female, the remains from Kendrick’s Cave showed a different ancestry. This individual, a male who lived about 13,500 years ago, shares ancestry with 14,000-year-old remains found in Villabruna, northern Italy. Such ancestry is associated with western hunter-gatherers who expanded from south-east Europe or the near east.

The researchers say the results suggest Kendrick’s Cave may have had multiple occupations.

Dr Selina Brace, a co-author of the study from the Natural History Museum, said the results were unexpected given a mixture of the two ancestries had previously been found in older human remains from southern Europe, with the new study revealing Cheddar Man also had such dual ancestry.

The team said the results suggest that at least two different human groups, with different ancestries, diets and cultures – including funerary practices – were present in Britain at the end of the last ice age.

However, Dr Rhiannon Stevens, a co-author of the work from University College London, said the study only looked at two individuals, meaning cautionwas needed when trying to draw together the different data. For example, she said, Magdalenian people elsewhere in Europe were known to have eaten fish.

Prof Paul Pettitt of Durham University, who was not involved in the research, said archeological work had previously revealed that the Gough’s Cave and Kendrick’s Cave humans were not contemporaries, and had offered clues as to their diet and ancestry.

But he said the new research highlighted the power of ancient DNA analysis to solve the mystery of whether abrupt changes in culture in prehistory were caused by population movements and ruptures, or by the spread of ideas – with the research suggesting that in this case the former was at play.

“In keeping with what prehistorians have long known about the highly mobile, small populations of ice age hunter-gatherers, this [research] adds evidence to the growing picture of remarkably small, ecologically fragile human groups spread thinly across late Pleistocene Europe,” he said.

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