A Winter’s Trail
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چکیده
Before migrating into North America, early humans first moved into Arctic Siberia and adapted to its harsh environment. The few oldest sites have been dated to at most about 15,000 years ago or so, which was after the major Northern Hemisphere ice sheets had begun to recede. Pitulko et al. (p. 52; see the cover and the news story by Stone) now report a series of radiocarbon ages and artifacts found in a terrace along the Yana River (just south of its mouth into the Arctic Ocean, in central Siberia) that date to 27,000 radiocarbon years ago (about 30,000 calendar years). Artifacts include an ivory foreshaft from the horn of a rhinoceros, two others made from mammoth tusk, and several hundred stone points and flakes.
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تاریخ انتشار 2003