Crop Biotech Update

New Evidence Shows Sweet Potato Came Before Humans; Says No Early Contact Between America and Polynesia

April 18, 2018

New research led by Oxford University reveals that sweet potato likely arrived naturally in Polynesia in pre-human times, challenging the belief that one of the world's most important crops was transported from America to Polynesia by people.

Christopher Columbus' arrival in America in 1492 marked the beginning of the great age of exploration in the world. The early presence of sweet potato in Polynesia has been widely interpreted as strong evidence for contacts between Polynesians and Americans in the Pre-Columbian era, whereas the possibility that the sweet potato crossed the Ocean through natural dispersal has received little attention.

Led by Professor Robert Scotland and Post Doctoral students Pablo Muñoz-Rodríguez and Tom Carruthers from Oxford's Department of Plant Sciences, with contributions from The International Potato Centre, Oregon State University, and Duke University, the new report published in Current Biology is the first complete study of the evolution and origin of sweet potato.

The research findings reveal that sweet potato was not brought to Polynesia by humans, but that it probably traveled from America by natural means. It was also revealed that the earliest collection of sweet potato from Polynesia, collected in 1769 during Captain Cook's voyage in the Endeavour, represents a distinct variety that originated before humans colonized the region. This evidence challenges the claim that there were pre-Columbian contacts between Polynesia and South America, even more considering that the early presence of sweet potato in the region has been presented as one of the main proofs of those contacts.

Read more details in the news release from the University of Oxford.