Genetic Studies Link Indigenous Peoples in the Amazon and Australasia (+Video)

A Harvard Medical School study is reshaping our understanding of how the indigenous people arrived in the Americas. Well-established assumptions are wrong.
Genetic Studies Link Indigenous Peoples in the Amazon and Australasia (+Video)
Left: A young man participates in a Native ritual in the Amazon in Brazil. (Filipe Frazao/iStock) Right: An Aboriginal man performs on Australia Day in Sydney, Australia, on Jan. 26, 2014. PhotographyByDonnaG/iStock
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Native Americans living in the Amazon bear an unexpected genetic connection to indigenous people in Australasia, suggesting a previously unknown wave of migration to the Americas thousands of years ago, a new study has found.

“It’s incredibly surprising,” said David Reich, Harvard Medical School professor of genetics and senior author of the study. “There’s a strong working model in archaeology and genetics, of which I have been a proponent, that most Native Americans today extend from a single pulse of expansion south of the ice sheets—and that’s wrong. We missed something very important in the original data.”


First author Pontus Skoglund explains his team’s new hypothesis about the ancient migrations that gave rise to today’s Native Americans. Video: Stephanie Dutchen

Previous research had shown that Native Americans from the Arctic to the southern tip of South America can trace their ancestry to a single “founding population” called the First Americans, who came across the Bering land bridge about 15,000 years ago. In 2012, Reich and colleagues enriched this history by showing that certain indigenous groups in northern Canada inherited DNA from at least two subsequent waves of migration.

The new study, published July 21 in Nature, indicates that there’s more to the story.

"There's a strong working model in archaeology and genetics ... that most Native Americans today extend from a single pulse of expansion south of the ice sheets—and that's wrong."
David Reich, Harvard Medical School
Stephanie Dutchen
Stephanie Dutchen
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