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
William Willis (sailor) effect Bernard Carnot's escape, which he eventually accomplished. During his first solo expedition in 1954 from South America to American Samoa, he sailed 6,700 miles – 2,200 miles farther than did Thor Heyerdahl on Kon-Tiki. His raft was named "Seven Little Sisters" and was crewed by himself, his parrot, and cat. Willis was age 61 at the time of this voyage. In a second great voyage ten years later, at the age of 71, he sailed 10,000 miles from South America to Australia single-handing a 34-foot (10.4 m) raft named "Age Unlimited". He left Callao on 5 July 1963, made