Thor Heyerdahl got it backwards. More than 40 years ago, the late explorer proposed that the Inca or their predecessors voyaged from South America to Polynesia by raft. On the contrary, a new study indicates that Polynesian seafarers reached what's now Chile by about 620 years ago. That conclusion hinges on the first evidence of when chickens arrived in the Americas.
A team led by anthropologist Alice A. Storey of the University of Auckland in New Zealand used radiocarbon dating and a comparison of ancient DNA to determine a Polynesian origin for a chicken bone previously unearthed at Chile's El Arenal site. Mitochondrial DNA extracted from the El Arenal bone contains an exact copy of a genetic sequence that appears in comparable DNA from 600-to-2,000-year-old chicken bones found in Tonga and American Samoa. Those islands lie 6,000 miles west of Chile.