New Guinea sago gatherers

Records of fertility and infant mortality were collected from the twenty‐five women who had completed their reproductive cycle and who were part of a population living on the Wogamus River in the Upper Sepik region of New Guinea. The mean number of live births was 5.3. Infant and early childhood mortality was 43.2 per cent. Eleven per cent of infants are killed at birth, most of them females born too soon after an older sibling. Both infanticide and post‐partum taboos on sexual intercourse lasting at least two years are explicitly practiced to ensure the adequate nutrition of the older sibling. The pattern of family limitation is related to subsistence on wild food resources, including sago.