for National Geographic News
A clump of frozen human hair from northwest Greenland suggests that the first Eskimos in the New World did not descend from Native Americans as previously thought but came directly from Asia, a new study says.
Furthermore, these pioneer settlers of the far north later died out and did not give rise to the Inuit living in Greenland today.
The research is based on DNA analysis of ancient hair from a so-called Paleo-Eskimo, which was found preserved in permafrost soil in the Disco Bay area in the 1980s.
The hair, which belonged to a male who lived some 4,000 years ago, has provided the first ever complete mitochondrial genome for an ancient human, according to a team led by Tom Gilbert of the Center for Ancient Genetics at the University of Copenhagen, Denmark.
Mitochondrial DNA is passed down from mother to child and thus gives a genetic marker to an individual's maternal ancestry.
In the ancient Greenland Eskimo's case, his hair revealed that his people came from Siberia, the study found.
The Paleo-Eskimo's genetic relatives survive today only in small pockets in northeastern Siberia and the Aleutian Islands, which stretch across the Bering Sea from Alaska to Russia, Gilbert said. (See a map of the islands.)
Previously, there were two main theories to explain the ancestry of the first Eskimos in Alaska, Canada, and Greenland, Gilbert said.
The theories held that they either descended from Native Americans who colonized North America at least 14,350 years ago, or they came from the same source area in Siberia that gave rise to modern Eskimos, such as those who have lived in Greenland for the past 1,000 years.
"Then there is a third idea that they were independent to both—and that's what it turns out to be," Gilbert said.
The new research, which appears tomorrow in the journal Science, suggests that the original Paleo-Eskimos of the New World were replaced by later colonizers, who spread eastward from Siberia.
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