Amazonians share an unexpected genetic link with Asian islanders, [View all]

[Ichingcarpenter]

Skoglund’s discovery — which is published online on 21 July in Nature2 — was that members of two Amazonian groups, the Suruí and the Karitiana, are more closely related to Papua New Guineans and Aboriginal Australians than other Native Americans are to these Australasian groups. The team confirmed the finding with several statistical methods used to untangle genetic ancestry, as well as additional genomes from Amazonians and Papuans. “We spent a lot of time being sceptical and incredulous about the finding and trying to make it go away, but it just got stronger,” says Reich.

Their explanation is that distant ancestors of Australasians also crossed the Bering land bridge, only to be replaced by the First Americans in most of North and South America. Other genetic evidence suggests that modern-day Australasians descend from humans who once lived more widely across Asia. “We think this is an ancestry that no longer exists in Asia, which crossed Beringia at some point, but has been overwritten by later events,” Reich says. The team calls this ghost population “Population Y”, after the word for ancestor, Ypykuéra, in the languages spoken by the Suruí and Karitiana. They contend that Population Y reached the Americas either before or around the same time as the First Americans, more than 15,000 years ago.



http://www.nature.com/news/ghost-population-hints-at-long-lost-migration-to-the-americas-1.18029?WT.mc_id=TWT_NatureNews

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