Polynesian navigation snow. In the mid-20th century, Thor Heyerdahl proposed a new theory of Polynesian origins (one which did not win general acceptance), arguing that the Polynesians had migrated from South America on balsa-log boats. The presence in the Cook Islands of sweet potato that is a plant native to the Americas (called "kūmara" in Māori), which have been radiocarbon-dated to 1000 CE, has been cited as evidence that Americans could have traveled to Oceania. The current thinking is that sweet potato was brought to central Polynesia circa 700 CE and spread across Polynesia from there, possibly by Polynesians who had traveled
Anthony Smith (explorer) younger than 56) departed from La Gomera in the Canary Islands in a custom-built raft, with the intention of crossing the Atlantic Ocean within three months, eventually arriving in Eleuthera. The raft, which was given the name "An-Tiki" in reference to the "Kon-Tiki" raft used by Norwegian explorer and writer Thor Heyerdahl in his 1947 expedition from South America to the Polynesian islands, was assembled during November and December 2010. To find crew mates Smith placed an ad in the Telegraph in 2006, which simply read: ""Fancy rafting across the Atlantic? Famous traveller requires 3 crew. Must be OAP. Serious