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 A new analysis challenges the out-of-Europe hypothesis, which has
figured in a political debate over the rights of present-day Native
American tribes. Scientists announced on Wednesday that they had,
for the first time, determined the full genome sequence of an
ancient American, a toddler who lived some 12,600 years ago and was
buried in western Montana. His DNA, they report, links today's
Native Americans to ancient migrants from easternmost Asia. The study, published in the journal Nature, "is the final shovelful
of dirt" on the European hypothesis, said anthropological geneticist
Jennifer Raff of the University of Texas, co-author of a commentary
on it in Nature. The idea that the first Americans arrived millennia earlier than
long thought and from someplace other than Beringia — which spans
easternmost Russia and western Alaska — has poisoned relationships
between many Native Americans and anthropologists. Some tribes fear
that the theory that the continent's first arrivals originated in
Europe might cast doubt on their origin stories and claims to
ancient remains on ancestral lands.
 Despite the new study, other experts say the debate over whether the
first Americans arrived from Beringia or southwestern Europe, where
a culture called the Solutrean thrived from 21,000 to 17,000 years
ago, is far from settled. "They haven't produced evidence to refute the Solutrean hypothesis,"
said geneticist Stephen Oppenheimer of Oxford University, a leading
expert on using DNA to track ancient migrations. "In fact, there is
genetic evidence that only the Solutrean hypothesis explains."
ELK ANTLERS The partial skeleton of the 1-year-old boy, called Anzick-1, was
discovered when a front-end loader hit it while scooping out fill in
1968. The grave and its environs contained 125 artifacts including
stone spear points and elk antlers centuries older than the bones,
said anthropologist Michael Waters of Texas A&M University's Center
for the Study of the First Americans, a co-author of the Nature
study. That suggests that the antler artifacts "were very special heirlooms
handed down over generations," Waters said. Why they were buried
with the boy remains unknown. The distinctive stone tools show that the boy was a member of the
Clovis culture, one of the oldest in North America and dating to
around 12,600 to 13,000 years ago. The origins and descendants of
the Clovis people have remained uncertain, but the boy's genome
offers clues. "The genetic data from Anzick confirms that the ancestors of this
boy originated in Asia," said Eske Willerslev of the Natural History
Museum of Denmark, who led the study. The DNA shows that the child
belonged to a group that is a direct ancestor to as many as 80
percent of the Native Americans tribes alive today, he said: "It's
almost like he is a missing link" between the first arrivals and
today's tribes.
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The most likely scenario, said Texas's Raff, is that humans reached
eastern Beringia from Siberia 26,000 to 18,000 years ago. By 17,000
years ago, receding glaciers allowed them to cross the Bering
Strait. Some migrated down the Pacific coast, reaching Monte Verde
in Chile by 14,600 years ago, while others — including the ancestors
of Anzick-1 — headed for the interior of North America. The genetic analysis found that the boy is less closely related to
northern Native Americans than to central and southern Native
Americans such as the Maya of Central America and the Karitiana of
Brazil. That can best be explained, the scientists say, if he
belonged to a population that is directly ancestral to the South
American tribes. Today's Native Americans are "direct descendants of the people who
made and used Clovis tools and buried this child," the scientists
wrote. "In agreement with previous archaeological and genetic
studies, our genome analysis refutes the possibility that Clovis
originated via a European migration to the Americas." Not all experts are convinced. "We definitely have some stuff here
in the east of the United States that is older than anything they
have in the west," said anthropologist Dennis Stanford of the
Smithsonian Institution, a proponent of the out-of-Europe model.
"They've been reliably dated to 20,000 years ago," too early for
migrants from Beringia to have made the trek, he said, and strongly
resemble Solutrean artifacts. Genetic analysis is also keeping the out-of-Europe idea alive. One variant of DNA that is inherited only from a mother, called
mitochondrial DNA, and is found in many Native Americans has been
traced to western Eurasia but is absent from east Eurasia, where
Beringia was before the sea covered it, Oppenheimer explained. For
the variant, called X2a, to have such a high frequency in Native
Americans "it must have got across the Atlantic somehow," he said.
The new study "completely ignored this evidence, and only the
Solutrean hypothesis explains it."
 The scientists hope the Anzick boy has yielded all his secrets: He
will be reburied by early summer.
(Reporting by Sharon Begley; editing by Michele Gershberg and
Douglas Royalty)
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