Finding rewrites the evolutionary history of the origin of
potatoes Oct. 3, 2005 Humans have cultivated potatoes for
millennia, but there has been great controversy about the
ubiquitous vegetable's origins. This week, writing in the
Proceedings of the National Academies of Sciences, a team led by
a USDA potato taxonomist stationed at UW-Madison has for the
first time demonstrated a single origin in southern Peru for the
cultivated potato. The scientists analyzed DNA markers in 261
wild and 98 cultivated potato varieties to assess whether the
domestic potato arose from a single wild progenitor or whether
it arose multiple times - and the results were clear, says David
Spooner, the USDA research scientist who led the study. "In
contrast to all prior hypotheses of multiple origins of the
cultivated potato, we have identified a single origin from a
broad area of southern Peru," says Spooner, who is also a UW-
Madison professor of horticulture. "The multiple-origins theory
was based in part on the broad distributio