Evolutionary Biology and the Natural Selection of Behavior

Abstract

Evolution is a name for how biological populations have changed over the history of our planet. The most successful theory of why those populations have changed is Darwin's natural selection. Accounts of evolution tend to emphasize anatomical and physiological properties, such as the brain and its organization. But evolutionary contingencies select organisms based on what they can do, so brains and other structures evolved in the service of behavior. In that sense, behavior always comes first. Selection as a causal mode differs from traditional push–pull causalities. It extends from the familiar level of phylogeny (i.e., evolutionary change over generations) to ontogeny (i.e., behavior that evolves within the lifetime of an individual organism) and to sociogeny (i.e., evolving cultural practices, as behavior is passed on from some individuals to others). At each level behavior has consequences, and these consequences determine the extent to which the behavior is replicated and evolves.