Interesting theory.
When climate took a turn toward the cold tens of thousands of years ago, both Neanderthals and early humans started traveling further distances to find food, found a new study.
As a result, the two groups encountered each other often.. And a consequent boom in inter-species liaisons eventually led to the extinction of Neanderthals.
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"We are increasingly finding evidence of sophisticated behavior among Neanderthals, and now the question is: If they were so smart, why did they become extinct?" said Michael Barton, an anthropologist at Arizona State University in Tempe.
"Our answer is that they became extinct because they were so smart, not in spite of it," he said. "They were doing what everyone else was doing, and how they dealt with worldwide environmental change made their population and probably other endemic populations disappear."
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