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
Herman Watzinger which was cancelled because of World War II, and applied for a job in the U.S and sought a visa to the U.S. He met Thor Heyerdahl in New York City, where he was asked to participate in the construction of the Kon-Tiki raft and become a member of the expedition. On board the raft, where he was second in command, he was responsible for meteorological and hydrographic measurements. After the Kon-Tiki expedition, he returned to Lima in 1970, where he worked as head of fisheries, projects and advisor in freezing techniques for WR Grace & Co and Atlas. Watzinger