The vast majority of marriages are monogamous, but nonsororal polygynous marriages are allowed in the Dogon culture. However, even in polygynous marriages, it is rare for a man to have more than two wives. In a polygynous marriage, the wives reside in separate houses within the husband's compound. The first wife, or "ya biru," holds a higher position in the family relative to any wives from later marriages. Formally, wives join their husband's household only after the birth of their first child. The selection of a wife is carried out by the man's parents. Marriages are endogamous in that the people are limited to marry only persons within their clan and within their caste.