Genetic study uncovers Ice Age drama for people in Europe

Baku, March 9, AZERTAC
Europe was not a mild paradise during the Ice Age, as the vast glaciers that covered much of the continent made large swathes inhospitable to humans. But our species - a new immigrant to Europe - persevered, albeit with great difficulty, according to Reuters.
Researchers on Wednesday revealed an analysis of genome data from 356 hunter-gatherers who lived in the region between 35,000 and 5,000 years ago, a time span that spanned the coldest interval of the Ice Age between 25,000 and 19,000 years ago. This allowed them to decipher the population dynamics of prehistoric Europe, including the movement of human groups and some key physical traits.
While some populations huddled down and survived in relatively warmer parts of Europe, including France, Spain and Portugal, others died out in peninsular Italy, the study showed. It also gave insight into the emergence of traits such as fair skin and blue eyes in Europeans.
“It is the largest ancient genomic data set of European hunter-gatherers ever created,” said paleogeneticist Cosimo Posth of the University of Tübingen in Germany, lead author of the study, published in the journal Nature.
“It refreshes our knowledge of how humans survived the Ice Age,” added paleogeneticist and study co-author He Yu of Peking University in China.
Europe was the domain of the Neanderthals, our hardy and big-browed cousins, but they died out about 40,000 years ago when our species, Homo sapiens, took root on the continent. Homo sapiens originated in Africa about 300,000 years ago, then spread worldwide and reached Europe at least 45,000 years ago.
Various groups of hunter-gatherers roamed the European countryside, hunting large mammals including woolly mammoths, woolly rhinos, and reindeer, and gathering edible plants. During the coldest period of the Ice Age, known as the Last Glacial Maximum, ice sheets called continental glaciers covered half of Europe, with much of the remainder lying in tundra conditions with frozen subsoil.
The only people who survived this hardest period in Europe were hunter-gatherers who had taken refuge in parts of France and the Iberian Peninsula, the study found. The Italian peninsula, which was once believed to be a haven for people during this period, was just the opposite - all of its inhabitants perished.
“It comes as a great surprise that humans died out on the Italian peninsula,” said study leader Johannes Krause, director of the Max Planck Institute for Evolutionary Anthropology in Germany.
This region was resettled about 19,000 years ago by hunter-gatherers from the Balkans, who subsequently spread across Europe, replacing everyone who had lived there by about 14,500 years, the researchers found.
“About 14,000 to 13,000 years ago, the climate became warmer and most parts of Europe gradually turned into forest, similar to today,” Yu said.
The Homo sapiens individuals who came to Europe after migrating from Africa were black. Genome data showed a shift towards lighter skin in humans in Europe between 14,000 and 8,000 years ago, which accelerated with the subsequent spread of agriculture across the continent.
Certain characteristics of Western European hunter-gatherers, known for blue eyes and dark skin, differed from their Eastern European counterparts, who had light skin and dark eyes. These two populations only began to interbreed around 8,000 years ago, after the first farmers from Anatolia - modern Turkey - arrived in Europe and all hunter-gatherers pushed north.
The genome data showed that populations associated with what is known as the Gravettian culture, dating from around 34,000 to 26,000 years ago - known for certain types of stone tools, cave paintings and small sculptures called “Venus” figures - were in fact not homogeneous . Instead, there were two largely independent populations that shared cultural traits.
“A big surprise to me,” Yu said, “is the fact that Gravettian populations carried two genetically distinct ancestors and that one of them disappeared from Europe.”

Technology 2023-03-09 11:49:00