Though they inhabited a remote speck of land in the middle of the Pacific, with their closest neighbors living on an island 1,100 miles (1,770 km) away, the Polynesian people who populated Easter Island, or Rapa Nui, erected huge stone figures that still stare enigmatically from the hillsides. But this ancient group was not as isolated as long believed. A genetic study, published in the latest edition of the journal Current Biology, found these ancient people had significant contact with Native American populations hundreds of years before the first Westerners reached the island in 1722.
The Rapa Nui people are best known for the 900 monumental head-and-torso stone statues, known as moai, covering the Easter Island. The culture flourished starting around 1200 until falling into decline by the 16th century.
Genetic data on 27 Easter Island natives indicated that interbreeding between the Rapa Nui and native people in South America occurred roughly between 1300 and 1500.
“We found evidence of gene flow between this population and Native American populations, suggesting an ancient ocean migration route between Polynesia and the Americas,” said geneticist Anna-Sapfo Malaspinas of the Center for GeoGenetics at the University of Copenhagen, who led the study.
The genetic evidence can only indicate the mating of the two people groups, suggesting that Rapa Nui people journeyed to South America or that Native Americans traveled to Easter Island. Due the to the great distances required to make the round trip, researchers are leaning towards the theory that the Rapa Nui people made the arduous ocean voyages.
“It seems most likely that they voyaged from Rapa Nui to South America and brought South Americans back to Rapa Nui and admixed with them,” said Mark Stoneking, a geneticist withGermany’s Max Planck Institute for Evolutionary Anthropology who collaborated on a related study of Brazil’s indigenous Botocudo people. “So it will be interesting to see if in further studies any signal of Polynesian, Rapa Nui ancestry can be found in South Americans.”
To make these longs, often perilous trips to South America and back, the Rapa Nui people likely spent arduous weeks in wooden canoes.
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.
A second study, also published in Thursday’s issue of Current Biology, illustrates another case of Polynesians venturing into South America. Two ancient human skulls from Brazil’s indigenous Botocudo people, known for the large wooden disks they wore in their lips and ears, belonged to people who were genetically Polynesian, with no detectable Native American ancestry.
“How the two Polynesian individuals belonging to the Botocudos came into Brazil is the million-dollar question,” said University of Copenhagen geneticist Eske Willerslev of the Center for GeoGenetics, who led the study on the Botocudos.