This introduction to the evolutionary and developmental principles underlying the study of animal behavior provides a broad view of behavior from the comparative psychology perspective. The author discusses all aspects of the subject— including comparative learning and cognition, brain evolution and behavior, primate evolution, behavior genetics, behavioral ecology, social behavior in an ecological context, early experience and development, and the ontogeny of social behavior. Emphasizing problems and research interests that have traditional relevance for psychologists, the text uses examples drawn from specialized journals to provide a firm grasp of evolutionary science as it is applied to the understanding of behavior.