Kayapo

The Kayapo (Portuguese: Caiapó [kajaˈpɔ]) people are the indigenous people in Brazil who inhabit a vast area spreading across the states of Pará and Mato Grosso, south of the Amazon River and along the Xingu River and its tributaries. This pattern has given rise to the nickname the Xingu tribe. They are one of the various subgroups of the great Mebêngôkre nation (people from the water’s source). The term "Kayapo" is used by neighbouring groups rather than the Kayapo themselves. They refer to outsiders as "Poanjos".

The type of sweet potato that forms an important part of the Kayapó diet is sometimes named "caiapo", after the tribe. It is cultivated under that name in Japan, and has been found to have health benefits.