Some
people enjoy eating sweet potatoes. Sweet potatoes are the thick, edible
roots of the plant classified as Ipomoea batatas, which is native to tropical
South America. The existence of the sweet potato on Easter Island and
in Polynesia have given historians and anthopologists the problem of explaining
how exactly they got there.
Thor Heyerdahl, a world-renowned Norwegian explorer and archaeologist, lived for a year on the isolated island of Fatuhiva in the Marquesas Group. He argued that the Pacific Islanders could have originated from pre-Inca period South Americans who sailed to the west in the prevailing westerly trade winds, especially if they had been aided by El Nino. Convinced that human settlers had come with the ocean currents from the west, he took off from South America in 1947 on a balsa raft (the Kon Tiki) and drifted 4,300 nautical miles before running aground on a reef near the Polynesian island Puka Puka 3 months later. He also threw in another factor to support his theory - the similarity of style between Easter Island and Incan stonework.
Here you can see the sea wall of ahu Vinapu I at Vinapu (left), which has been likened to Inca masonry(right).
Taken by Clive Ruggles. Do note that similarities are not limited to these photos.
However, his theories run up a wall when faced with the similarities the Easter Islanders have with the South East Asian peoples. According to the Tenth Pacific Science Congress held at Honululu in 1961, "Southeast Asia and the islands adjacent constitute one major source area of the peoples and cultures of the Pacific Islands and South America".
While the Easter Islanders may not have originated from South America, it is possible they might have had communication links with them.