for National Geographic News
Neandertals in western Europe were ravaged by an increasingly hostile climate rather than an invasion of modern humans, according to new research.
Beset by freezing conditions and food shortages, populations of Neandertals (often spelled "Neanderthals") dwindled between 40,000 and 35,000 years ago, the research suggests.
Modern humans, meanwhile, didn't settle western Europe until much later than had been thought, the study says.
The findings challenge the commonly held view that modern humans migrated to Europe from Africa about 40,000 years ago and quickly outcompeted or slaughtered their hairy, thickset cousins.
Instead, the new research supports the theory that Neandertals gave rise to the first modern humans in Europe.
Neandertals were the prehistoric ancestors of western Europeans, said Eugène Morin of Canada's Trent University in Ontario, lead author of the new study.
Morin argues that Neandertal populations thinned out gradually as Europe's environment became harsher, with some groups going extinct.
But climate stresses may have wrought evolutionary adaptations in surviving Neandertals, leading them to develop characteristics like those of modern humans, Morin added.
"Neandertals adapted to this harsher climate by expanding their social networks, a process that allowed the diffusion of 'modern traits' into the Neandertal gene pool," he said.
Some modern humans may have migrated to Europe during this period, Morin added, "but I don't think it happened to the large scale implied by many scholars."
Such an influx probably didn't occur until about 10,000 years ago, with the spread of agriculture from the Middle East, he said. (See an interactive map of ancient human migration.)
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