Gran Chaco people

The indigenous Gran Chaco people consist of approximately thirty-five tribal groups in the Gran Chaco of South America. Because, like the Great Plains of North America, the terrain lent itself to a nomadic lifestyle, there is little to no archaeological evidence of their prehistoric occupation. Contributing to this near-absence of archaeological data is the lack of suitable raw material for stone tools or permanent construction and soil conditions that are not conducive to the preservation of organic material.
Geography.
The actual cultural area of the Gran Chaco peoples differs from that of the geographic Gran Chaco. The northwestern boundary of the cultural area is the Parapetí River and the marshes of the Bañados de Izozog depression, beyond which were the lands of the cultural unrelated Chané and Chiriguano. The cultural boundaries have not been static, even during historical times. In the late 17th century the area expanded to the east across the Paraguay River, when the Mbayá invaded the lands between the Apa River and the Miranda River in Mato Grosso do Sul province in Brazil.
Languages.
The tribal groups of the Gran Chaco fall into six language families: