A new genomic study suggests that people from Easter Island, one of the planet’s most isolated islands, have been mingling with Native Americans hundreds of years before Europeans "discovered" the island in the 1700s. The findings, published in Current Biology this week, provides the first genetic support of an early trans-Pacific route between Polynesia and the Americas—an impressive 4,000 kilometer trek.
Easter Island, or Rapa Nui, is located in the easternmost corner of the Polynesian Triangle in the Pacific. Archaeological evidence suggests that the island was first colonized by Polynesians during their eastward expansion around 1200. About 30 to 100 Polynesian men, women, and children landed on the island in at least two double-hulled canoes. Some time after settling, the Rapanui built giant stone platforms and over 900 statues that weighed as much as 82 tons. It wasn't until 1722 when Dutch commander Jakob Roggeveen arrived with his ships. There have been suggestive evidence supporting the possibility of Native American contact prior to the European “discovery” of the island. For example, the presence of crops native to the Americas, including the Andean sweet potato.
To confirm these hints of pre-European contact, a team led by Natural History Museum of Denmark researchers genotyped and analyzed more than 650,000 different DNA subunits for 27 native Rapanui. The team found mostly Polynesian ancestry, however, eight percent of their genome were Native American, and 16 percent were European.
Then, by looking at the distribution of local ancestry tracts of eight unrelated Rapanui, the team dated the Native American admixture back between 1280 and 1495. The Rapanui began mixing with Europeans much later, between 1850 and 1895. The Rapanui people had significant contact with Native American populations between 19 and 23 generations ago.
Two possible scenarios would explain the genetic data: Either Native Americans sailed to Easter Island, or Polynesians made their way to the Americas and back. The researchers think it was the Rapanui who successfully sailed back and forth in voyages lasting between two weeks and two months. The trip from the Americas to Rapa Nui is far more challenging, especially since the island would be a tiny target in the vast Pacific. But it was certainly possible.
“Early human populations extensively explored the planet," says Anna-Sapfo Malaspinas from the museum’s Centre for GeoGenetics in a news release. "Textbook versions of human colonization events—the peopling of the Americas, for example—need to be re-evaluated utilizing genomic data."
Images: Natalia Solar (top), Natalia Solar (middle)