The ancient Rapanui people of Easter Island are largely mysterious to us today. We don’t know what drove the first settlers from their home in Polynesia to sail across the Pacific Ocean. We don't know why they settled on a 63-mile-square spot of land 1,100 miles away from the next island and 2,300 miles from the coast of South America. We don’t know why they carved hundreds of enormous stone giants—the moai—or how they moved those stones miles from the quarry where they were carved. And we don’t know what caused their society to collapse.
We have suspicions, of course. Perhaps they used ropes to "walk" the statues. Maybe rats ate all the palm trees. And while we still don’t know why these seafarers left Polynesia, we do now know that they made it all the way to South America. New DNA analysis of 27 living Rapanui shows that the Polynesian settlers of Easter Island met and mingled with South Americans sometime between 1300 and 1500, writes Will Dunham for Reuters.
The research team looked at how the fragments of DNA from European and Native American ancestry were shuffled throughout the genomes of the Rapanui islanders. The Native American DNA is more fragmented than the European DNA, they write, which suggests that mixing happened earlier. They reported their findings in Current Biology. Dunham writes:
The researchers concluded that the intermixing occurred 19 to 23 generations ago. They said Rapa Nui people are not believed to have started mixing with Europeans until much later, the 19th century. Malaspinas said the genetic ancestry of today's Rapa Nui people is roughly 75 percent Polynesian, 15 percent European and 10 percent Native American.
The Rapanui probably traveled back and forth between South America and Easter Island, perhaps to trade goods for sweet potatoes, Andrew Lawler writes for Science.
Striking out from Easter Island and successfully finding the long coast of another continent is one thing, but hitting that small target of an island on the way back demands some serious knowledge. So, Native Americans probably didn't make the converse trip by themselves — it seems more likely that they made the weeks-long journey back with the skilled Rapanui.