Marriage. Because all Tatuyo consider themselves related through common descent from the Celestial Anaconda, the men take their wives from the neighboring societies: Karapana, Taiwano, Barasana, Panena, Tuyuka, and Cubeo. The greater the distance between tribes, the rarer the marriages between them (although they are not forbidden). The ideal marriage is the exchange of sisters between two men belonging to two traditionally allied lineages. Marriages involving the exchange of women who are not sisters also occur, such as those of women exchanged between a man and his sister's son. Temporary residence can be matrilocal with bride-service, but it is ultimately virilocal. After a divorce a woman returns to her kin and takes up with another man. There are several cases of sororate. Polygyny, although permitted, is rather rare.
Domestic Unit. The domestic unit is the nuclear family, which, in case of serious conflict, can survive alone in a house in the forest. In general, however, the nuclear family is part of a larger unit, the maloca or longhouse, which constitutes the local group. The maloca is ideally comprised of the families of full brothers, each of which occupies a particular space, determined by birth, in the longhouse.
Inheritance. The Tatuyo have little property to transmit, but sons inherit from their fathers and daughters from their mothers. Social, political, religious, and ritual offices and the songs, incantations, and objects attached to them are inherited in the paternal line according to principles strictly determined by Tatuyo social organization.
Socialization. The Tatuyo lavish their children with affection and use physical coercion only exceptionally. Early on, children are told stories about ghosts ( wâti ) that haunt the forest foot paths at night, devouring those who foolishly leave the protection of the maloca. Later, the children are told the myths that trace the major outlines of Tatuyo culture. Rites mark the major phases in the separation of the sexes. At every stage of socialization the emphasis is on the cohesion of the group of brothers that forms the core of the community and on the individuality of young girls, who enter at marriage into the network of alliances. For a generation or two the Tatuyo hid their children so that they would not have to attend the mission school. Since the 1970s, however, the Tatuyo have wanted their children to be educated so that they would be better prepared for interactions with Whites.