via National Geographic.
Polynesian sailors, already credited with discovering and colonizing most of the Pacific islands, apparently also made it to South America - explaining the mystery of how chickens arrived there before Columbus "discovered" the New World. Ancient chicken bones found at a site in central Chile have been genetically identified as coming from SE Asia, the origin of the Polynesian seafarers. The bones appear to date from the 14 or 15th centuries.
"The researchers used carbon dating on the same bone used for DNA testing. The analysis suggested the bone was buried between A.D. 1320 and 1410. These dates, which fit well with those of other artifacts found at the same site, were determined with a dating technique called thermoluminescence. The dates of the Chilean chicken bones also roughly fit with when Polynesians would be expected to have reached the Americas, since they probably traveled eastward from Easter Island, which was first settled as late as A.D. 1200."