Peanut

The peanut is a legume grown mainly for its edible seeds, which develop underground in pods after the plant's flowers fertilize and bury themselves in the soil, an unusual habit called geocarpy. It was first domesticated in South America east of the Andes, in the region spanning present-day Peru, Bolivia, Argentina and Brazil, arising from a hybrid of two wild species; the oldest archaeological evidence of peanut pods, found in Peru, dates to roughly 7,600 years ago. It serves as both a food legume and an oil crop, and its remains are known in English by several regional names, including groundnut and goober.