Evolution and the Demand for Children

An interpretation of fertility transition is offered applying facts and theories of evolution to concepts and relationships in the literature on fertility determinants. The discussion is centered on a kin hypothesis involving 5 propositions: 1) Resource insolvency brought on by the birth of children has been an important selective pressure throughout human evolution and as a result humans have evolved to strive for social and economic success. 2) In traditional societies extended kinship networks function to disperse the costs of child rearing among an array of relatives. 3) The pursuit of social and economic success in societies undergoing modernization leads to the breakdown of these kinship networks; simultaneously there is a tremendous increase in the complexity and number of routes to social and economic success. 4) Following the breakdown of extended kinship networks child rearing costs are concentrated on parents thus potentially constraining the pursuit of social and economic success. 5) Also following the breakdown of extended kinship networks resources formerly controlled by the kin group (usually its elders) come under the control of young adults enabling them to concentrate resources on a small number of children. Once some parents concentrate their resources on small numbers of children other parents must follow suit if their offspring are to be socially competitive. Preliminary support for the kin hypothesis is established with data from the demographic and anthropological literature. (Authors) (Summaries in ENG FRE SPA)