Archaeologists used to think that the Clovis people were the first inhabitants of the Americas some 13,500 years ago. The ...
New genetic evidence supports the hypothesis that the first people in the Americas all came from northeast Asia by crossing a land bridge known as Beringia. When sea levels rose after the last ice ...
Fig. 1. Geography of Beringia and levels of UV radiation. (A) Map of Beringia today. Cross-hatching indicates the region in which levels of UVMED (defined as the amount of UV radiation that will ...
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