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
Kon-Tiki expedition sea. A book documenting the voyage and raft was released in 1948 by Thor Heyerdahl, called "". A film documentary about the voyage and raft was released in 1950, called "Kon-Tiki". It won the 1951 Oscar for Best Documentary Feature. "Kon-Tiki" is a 2012 Norwegian historical dramatized feature film about the 1947 "Kon-Tiki" expedition. It stars Pål Sverre Valheim Hagen as Thor Heyerdahl and is directed by Joachim Rønning and Espen Sandberg. It was the highest-grossing film of 2012 in Norway and the country's most expensive production to date. Kon-Tiki expedition The "Kon-Tiki" expedition was a 1947 journey by raft