A provocative new study argues Polynesians and Native Americans made contact some 800 years ago. That date would place their first meeting before the arrival of Europeans in the Americas and before the settlement of Easter Island (Rapa Nui), which has been suggested as the site of such an initial encounter.

Researchers, published in Nature, sampled genes of modern peoples living across the Pacific and along the South American coast and the results suggest that voyages between eastern Polynesia and the Americas happened around the year 1200, resulting in a mixture of those populations in the remote South Marquesas archipelago. It remains a mystery whether Polynesians, Native Americans, or both peoples undertook the long journeys that would have led them together. The findings could mean that South Americans, hailing from what’s now coastal Ecuador or Columbia, ventured to East Polynesia. Alternatively, Polynesians could have arrived in the Marquesas alone having already mixed with those South American people—but only if they’d first sailed to the American continent to meet them.

Alexander Ioannidis, who studies genomics and population genetics at Stanford University, co-authored the new study in Nature. “The genes show that the Native Americans who contributed came from the coastal regions of Ecuador and Columbia,” he says. “What they can’t show, and we don’t know, is where exactly it first took place—on a Polynesian island or the coast of the Americas.”