Archeologists have long believed the two regions made early contact, pointing to the early, widespread cultivation of a South American plant in Polynesia, a collection of more than 1,000 islands scattered over the Pacific Ocean.
The results of a genomic study now confirmed they did.
The researchers were looking for signs that prehistoric Polynesians and Indigenous Americans had children together, which would leave a clear genetic signature in their offspring -- called an admixture.
What they found was that people from several eastern Polynesian islands, including Rapa Nui -- also known as Easter Island -- have genetic traces in their DNA linked to indigenous South Americans. The genetic signatures showed a strong connection to the Zenu, an indigenous group from Colombia.
Researchers then traced the timing of their encounter by analyzing the length of the indigenous American genomic segments, and decided the initial admixture took place in the eastern islands of Polynesia around 1150-1230 A.D.
But in Rapa Nui, that admixture was dated much later to around 1380 A.D., despite the island being the closest to South America.
"Our analyses suggest strongly that a single contact event occurred in eastern Polynesia, before the settlement of Rapa Nui, between Polynesian individuals and a Native American group most closely related to the indigenous inhabitants of present-day Colombia," the study said.
How did they get there?
But what the study couldn't confirm is how exactly that encounter unfolded: Did the Polynesians voyage to South America and mix with the local people there, or did South Americans drift thousands of miles to the Pacific?
suggested that the sweet potato was first introduced to Polynesia between 1000 and 1100 A.D., most likely by Polynesian voyagers who reached the western coast of South America and brought back the crop, before spreading it to other Pacific islands.