From Living The Scientific Life blog in the USA:
This book details Heyerdahl’s voyage from Peru across the Pacific Ocean to the Tuamoto Islands where his crude raft eventually beached.
By carrying out this voyage, he was trying to show that his hypothesis was possible, that South American Indians could have rafted across the ocean, settling islands along the way.
“Scientists have not been willing to fully accept the idea” of prehistoric contact between Polynesia and South America, said said archeologist Terry L. Jones of Cal Poly San Luis Obispo, “but it is hard to understand why.”
However, there now is direct evidence that the Polynesians at least did make it across the Pacific Ocean: chicken bones found in Chile.
The chicken bones were recovered from a site called El Arenal-1 in south-central Chile, approximately a mile and a half inland on the southern side of the Arauco Peninsula.
Thermoluminescent dating of ceramics from the site indicates the site was occupied from AD 700 to 1390.
Radiocarbon dating revealed the chicken bones were about 622 years old.
Even with potential errors, that means they dated from somewhere between AD 1321 to 1407 — before Spaniards first made it to the New World.
Additionally, genetic analysis of the chicken bones showed that they were identical to genetic sequences of chickens from that same time period in American Samoa and Tonga, both islands that are more than 5,000 miles away from Chile.
“I was pretty excited when the dates came back as clearly pre-European. There were no questions.
The Europeans didn’t pick them up in Polynesia and bring them back,” said archeologist Elizabeth A. Matisoo-Smith of the University of Auckland, and senior author on the paper.
The new findings are published in the Proceedings of the National Academy of Sciences.
Previously, the most convincing evidence of contact between South Americans and Polynesians was the presence of sweet potatoes at archeological sites throughout Polynesia.
Sweet potatoes are a native plant from South America.
Additionally, sweet potatoes dating from about AD 1000 have been found on the Cook Islands.
Equally important, the name of the potato used throughout Polynesia is the same name given it by South Americans.
“If we know they landed in Chile,” said Jones, “then why is it so difficult to imagine they couldn’t have made it to Southern California from Hawaii?”
See also here.
Originally, chickens are not from Oceania, but from the forests of the Asian continent.
Chickens came with Columbus to the Americas, not earlier: here.
Two of Christopher Columbus’s shipmates were the first Africans to set foot in the New World, a study has found: here.
Henry Hudson: here.