Jan Bartek – AncientPages.com – Modern humans began to spread across Eurasia about 45,000 years ago. Still, previous research showed that the first modern humans that arrived in Europe did not contribute to later populations.

A new study published in Nature Ecology & Evolution 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.

Reconstruction of a hunter-gatherer ᴀssociated with the Gravettian culture (32,000–24,000 years ago), inspired by the archaeological findings at the Arene Candide site (Italy). Credit: Tom Bjoerklund

The team analyzed 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.

Climatic refugium or ᴅᴇᴀᴅ end?

Surprisingly, the research team found that populations from different regions ᴀssociated 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 ᴀssociated 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 favorable 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 ᴀssociated 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.

The prehistoric human groups that archaeologists refer to as Gravettian were widespread in Europe about 32,000–24,000 years ago. Despite sharing several similar cultural traits, Gravettian populations from western and eastern/southern Europe were genetically different. The west Gravettian population (left) survived during the Last Glacial Maximum while the eastern and south Gravettian populations disappeared. Credit: Michelle O’Reilly and Laurent Klaric, inspired by the original work by Benoit Clarys

“We find that individuals ᴀssociated 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.”