I am interested in the history of the spread of plants (and organisms, in general) around the world, and you should be too… Chances are, every meal you have ever eaten has been influenced by this exchange. The topic has been explored by Environmental Historian Alfred Crosby (among others) in a number of fascinating books such as Ecological Imperialism Cambridge University Press 1986, 1993, 2004, The Columbian Exchange: Biological and Cultural Consequences of 1492 Greenwood Press 1972, and Germs, Seeds, and Animals: Studies in Ecological History. M. E. Sharpe 1994.
The article below, by John Timmer, discusses the sweet potato (Ipomoea batatas) and the numerous indications that this important food crop may have initially been brought from S. America to Polynesia, Hawaii, and New Zealand (etc.) before the initiation of the European conquest of the Americas. “Archeological remains appear to place sweet potato cultivation in the core of Polynesia by the year 1200, and it spread with further migrations to places like New Zealand and Hawaii.”
Read more in the article snippet below and follow the link to view the article in full.
Polynesians reached South America, picked up sweet potatoes, went home
Tubers were spread from New Zealand to Hawaii before European contact.
by John Timmer
(From arstechnica.com) “The sweet potato was one of a number of crops domesticated in the Andes and, like many of the rest, it became a global crop in the colonial era. But there were some hints that the sweet potato may have already started its global sweep before the Europeans ever took a bite out of one. Some of the early European explorers, including Captain Cook, reported finding it in places like Hawaii. All of which implies that the Polynesians, who managed to spread widely across the Pacific, had made it all the way to South America.
“But it was difficult to be sure, given that European travelers later enhanced its spread within the Pacific and elsewhere. This has also created a complex genetic legacy that obscures its origins. Now, researchers have gone back and obtained DNA from museum samples, including some collected by Cook’s crew, and find that the DNA indicates that Polynesians made it as far as South America.”