Kin Groups and Descent. Kinship is closely associated with gender. The relation between siblings is a key metaphor for kinship, descent, marriage, and sociopolitical ties in myth and cosmology. But there is a clear male bias in that a male is said to have offspring originating from his penis ( kamare ) — his kamarima are his children and his brothers' children—and offspring from his anus ( wa )—his watako are his sisters' children. By contrast, a woman does not have metaphorical offspring from the front and behind. Yet, while males are considered to model the fetus by means of frequent coitus—explicitly likened to carving a "spirit pole" (see below)—it is women who ensure the succession and reproduction of human beings in matrilineal descent groups. Thus in kinship, as otherwise, women and men have a complementary relationship, each sex contributing in its distinctive way.
Kinship Terminology. Consistent with the structural importance of "siblingship," kinship terminology stresses "Horizontal" (generational) rather than "vertical" (lineal) ties and categories. It has a bilateral Hawaiian-type slant stressing generation and relative age. However, again gender comes in: "inferior" and "male" wife takers are terminologically distinguished from "superior" and "female" wife givers. The former, referred to as kaokapajti (sister's husband and daughter's husband) are required to render a wide variety of services. A man without kaokapajti is a social nobody. There are two modalities of matrilineal descent groups, each being associated with ideal preference for uxorilocal or matrilocal residence. The first modality, a vertical one, includes all matrilineal descendants of a named woman over three generations. In the fourth generation the focal point shifts to a woman of the Second generation. The second modality, a horizontal one, includes siblings and cousins who claim to have one maternal grandmother in common. The two modalities represented by various groupings constitute the core of people who share a tract of land ( taparè). The relationship between these groupings is usually putatively matrilineal.