Evolutionary Genetics

Abstract

Evolutionary forces of selection, mutation, migration, and genetic drift interact to maintain heritable individual differences. Resolving the ostensible paradox posed by the fact that heritable differences in personality and intelligence, in spite of their links to mortality and fertility, have not been driven to fixation, is within the purview of evolutionary genetics. We introduce the tool kit available to psychologists who want to understand these forces. It assembles complementary tools from molecular and behavior genetics, as well as classical evolutionary psychology, including the study of genome-wide associations, paternal age effects, inbreeding depression, developmental stability, and of course twins and families. We identify an unfortunate lack of cross-pollination, but map ways in which these disciplines, which share a common evolutionary metatheory, could test the tacit assumptions inherent in much of our work. Although it may take some time and may in some cases be impossible to identify the causative genes behind individual differences, we make the case that understanding the evolutionary forces involved in their maintenance is a worthy task in its own right, permitting us to understand and predict the effects of changing mores, policy, and demographic trends.