Demographic transition in ecological focus

Demographic transition theory posits that modernization, particularly in th e form of urban industrialism, fundamentally alters the environmental conte xt surrounding fertility decision-making, thereby reducing the advantages o f having children. While fertility research has either questioned the link between modernization and fertility or attempted to provide the intervening links between the two, there has been, little theoretical or empirical ref inement of the macrosocial/contextual principles of the theory. We argue th at human ecology and evolutionary theory can help respecify and revitalize demographic transition theory. Our respecification produces a more logical account of fertility decline that emphasizes the influences of service econ omies and the social adaptations attendant on ethnic heterogeneity and prei ndustrial social complexity. Analyses of changes in total fertility rates i n approximately 60 less-developed countries suggest: (I) general (if partia lly ambiguous) support for demographic transition theory, (2) confirmation of a robust effect of service-sector dominance on fertility, and (3) the im portance of ethnic homogeneity and preindustrial social complexity to demog raphic transition.