Parental Investment and Elite Family Structure in Preindustrial States: A Case Study of Late Medieval-Early Modern Portuguese Genealogies

In this paper I examine the idea that patriarchal family structure among elites in stratified societies originates as a form of parental investment favoring male children. Patriliny and restricted inheritance among 15th- and 16th-century Portuguese nobility are analyzed as reproductive strategies aimed at maximizing lineage survival and posterity in the face of high mortality. Demographic data derived from genealogies show that among the high nobility, males out reproduce females,whereas among the lower nobility, females outreproduced males, and that the tendency to concentrate investment in male offspring correspondingly increases with status. This family structural arrangement has the societal effect of generating intense competition among males for available titles, which results in increased warfare mortality among men and indirectly in the increased claustration of women