Polynesia of the plant in the Cook Islands have been radiocarbon-dated to 1000, and current thinking is that it was brought to central Polynesia c. 700 and spread across Polynesia from there, possibly by Polynesians who had traveled to South America and back. Thor Heyerdahl proposed in the mid-20th century that the Polynesians had migrated from the northwest coast of Canada by large whale-hunting dugouts, and from South America on balsa-log boats. Many anthropologists have criticised Heyerdahl's theory, including Wade Davis in his book "The Wayfinders". Davis says that Heyerdahl "ignored the overwhelming body of linguistic, ethnographic, and ethnobotanical evidence, augmented
Thor Heyerdahl excavations at such prominent sites as Orongo and Poike. The expedition published two large volumes of scientific reports ("Reports of the Norwegian Archaeological Expedition to Easter Island and the East Pacific") and Heyerdahl later added a third ("The Art of Easter Island"). Heyerdahl's popular book on the subject, "Aku-Aku" was another international best-seller. In "Easter Island: The Mystery Solved" (Random House, 1989), Heyerdahl offered a more detailed theory of the island's history. Based on native testimony and archaeological research, he claimed the island was originally colonized by Hanau eepe ("Long Ears"), from South America, and that Polynesian Hanau momoko ("Short