Why Did Hunter-gatherer Group in Europe Unexpectedly Disappear After the Last Ice Age?
A recent study has shown that a group of hunter-gatherers had survived the last Ice Age while living in the modern location of Europe, only to unexpectedly disappear about 14,500 years ago.
As the Newspaper El País reports, when scientists began to study the genetic material of humanity’s ancient ancestors about 30 years ago, they commenced on a quest for knowledge about a time in our collective past that was generally believed to have been lost forever. Several studies that have arisen since then have shown that all of the hard work has not been in vain.
Now, research including Johannes Krause, director of the Max Planck Institute for the Science of Human History and published in the journal Current Biology , has analyzed the genes of 35 individuals who lived between 35,000-7,000 years ago in modern France, Germany, Belgium, Italy, Czech. Republic, and Romania. The results of their study are surprising.
About 25,000 years ago, the last Ice Age began and froze about half of the world, causing many prehistoric humans to seek shelter in the south of Europe. The chilling temperatures and the consequences of this greatly reduced the human population in the area and subsequently decreased diversity in the groups that survived.
About 25,000 years ago the last Ice Age began, which froze about half of the world and caused many prehistoric humans to seek shelter in the south of Europe. Artistic representation of the last Ice Age. (Ittiz/CC BY – SA 3.0 )
The current study found that the mitochondrial DNA of three of the individuals, who correspond to modern France and Belgium and lived before the Last Glacial Maximum (the coldest period in the last Ice Age), were from haplogroup M.
This was a shock to the researchers, as Cosimo Posth of Tübingen University, the lead author of the study reported:
“I couldn’t believe it. The first time I got this result I thought it must be a mistake, because in contemporary Europeans haplogroup M is effectively absent, but is found at high frequency in modern Asians, Australians and Native American populations.”
These results suggest that haplogroup M existed in Europe relatively recently and provide evidence for the hypothesis that “all non-Africans quickly dispersed from a single group at a specific time, which scientists believe occurred around 50,000 years ago.” [Via The Independent ]
However, the questions arise: What happened to make this group of hunter-gatherers disappear from the region of Europe 14,500 years ago? How is it that they survived the chilling Ice Age only to fail to survive the subsequent warming?
Dr. Krause told El País :
“Regarding what happened to them, we can only speculate, and think that perhaps these people had adapted to the cold climate or to hunt mammoths, and that people better adapted to the warmer climates came in later from the near East or from the southeast of Europe. We don’t know who replaced them or where they came from for sure, however, their DNA can help us better pinpoint where they may have come from.”
Map of human migration based on mitochondrial haplogroups. Pink corresponds to areas dominated by haplogroup M and their offspring in indigenous populations. (Maulucioni/ CC BY SA 3.0 )
Carles Lalueza Fox , researcher with CSIC in the Institute of Evolutionary Biology of Barcelona, agrees with the results of the study, saying that they can be linked to some of his own research. “When we studied La Braña (a site located in León, Spain) we saw evidence for low genetic diversity and a diminished population in mitochondrial DNA of the Mesolithic.”
Lalueza Fox explained that normally there is some amount of continuity between different cultures, however the change in Europe 14,500 years ago was very brisk. The disappearance of the hunter-gatherer group also coincides with the rise of the Magdalenian culture . This too may suggest that the hunter-gatherer group was weakened for some reason and overtaken by newcomers who were better suited to the climate.
Featured Image: ‘The Stone Age’ (1882-1885), detail of a painting by Viktor M. Vasnetsov. Source: Public Domain
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