WASHINGTON POST PHOTOS
This 12,000-year-old skull of a 15-year-old
girl is shown as it was discovered in an underwater Mexican cave in 2007, resting against
the skeleton’s left humerus (upper arm bone).
DNA collected from one of the molars of the
skull reveals a direct connection to the people
who crossed the Bering straits from Siberia
more than 18,000 years ago.
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