Rivers and valleys constitute the natural boundaries for an ayllu. Tributaries flow into the Charazani and Calaya rivers and form triangulated land masses with various ecological features. The Callahuaya classify ayllu according to three major altitudinal levels: low, central, and high. The primary economic activity corresponding to each zone is growing maize (cereals), cultivating potatoes, and raising llamas. After the agrarian reform of 1954, the ayllu system diminished in importance, with attention given instead to separate communities and Bolivian political units such as cantons, provinces, and peasant syndicates. The Callahuaya now recognize nine ayllus: Amarete, Chajaya, Chari, Chullina, Curva, Inca, Calaya, Kaata, and Upinhuaya. The people live in small adobe houses (4 by 5 meters), one for cooking, another for sleeping, and one for storage. The houses form three sides of a courtyard, and a wall with a gate encloses the patio where the Callahuaya weave, raise chickens and guinea pigs, and socialize. Burros, pigs, and sheep are kept in open corrals behind sleeping quarters.