London: The genetic ancestry of the earliest Europeans survived the ferocious Ice Age that took hold after the continent was initially settled by modern people, a new study has found.
A ground-breaking new study carried on DNA recovered from a fossil of one of the earliest known Europeans - a man who lived 36,000 years ago in Kostenki, western Russia - has shown that the earliest European humans' genetic ancestry survived the Last Glacial Maximum: the peak point of the last ice age.
The study also uncovers a more accurate time scale for when humans and Neanderthals interbred, and finds evidence for an early contact between the European hunter-gatherers and those in the Middle East - who would later develop agriculture and disperse into Europe about 8,000 years ago, transforming the European gene pool.
Scientists now believe Eurasians separated into at least three populations earlier than 36,000 years ago: Western Eurasians, East Asians and a mystery third lineage, all of whose descendants would develop the unique features of most non-African peoples - but not before some interbreeding with Neanderthals took place.
By cross-referencing the ancient man's complete genome - the second oldest modern human genome ever sequenced - with previous research, the team discovered a surprising genetic "unity" running from the first modern humans in Europe.
The study suggests that a 'meta-population' of Palaeolithic hunter-gatherers with deep shared ancestry managed to survive through the Last Glacial Maximum and colonise the landmass of Europe for more than 30,000 years.
While the communities within this overarching population expanded, mixed and fragmented during seismic cultural shifts and ferocious climate change, this was a "reshuffling of the same genetic deck" said scientists.
European populations as a whole maintained the same genetic thread from their earliest establishment out of Africa until Middle Eastern populations arrived in the last 8,000 years, bringing with them agriculture and lighter skin colour.
"That there was continuity from the earliest Upper Palaeolithic to the Mesolithic, across a major glaciation, is a great insight into the evolutionary processes underlying human success," said co-author Dr Marta Mirazon Lahr, from Cambridge University's Leverhulme Centre for Human Evolutionary Studies (LCHES).
"For 30,000 years ice sheets came and went, at one point covering two-thirds of Europe. Old cultures died and new ones emerged - such as the Aurignacian and the Grevettian - over thousands of years, and the hunter-gatherer populations ebbed and flowed.
"But we now know that no new sets of genes are coming in: these changes in survival and cultural kit are overlaid on the same biological background," Lahr said.