New data indicates that some Polynesians carry Native American DNA

Enlarge / The Tongariki site, built by Polynesians on Rapa Nui. New data suggests that by the time their ancestors arrived on the island, they had already had contact with South America. (credit: Andres Moreno-Estrada)

The Polynesians were the greatest explorers of the world. Starting from Taiwan, they sailed across vast stretches of the Pacific, settling—and in some cases, continuing to trade between—astonishingly remote islands from New Zealand to Hawaii. But it's never been quite clear whether they made the final leap, sailing from Rapa Nui to reach the nearest major land mass: South America.

There are some hints that they have, primarily the presence of South American crops throughout the Pacific. But there has been no clear genetic signature in human populations, and the whole analysis is confused by the redistribution of people and crops after the arrival of European sailors.

Now, a new study finds clear genetic indications that Polynesians and South Americans met—we've just been looking at the wrong island—and wrong part of South America—for clear evidence. The researchers also raise a tantalizing prospect: that South Americans were already living on a Polynesian island when the Polynesians got there.