Biological approaches to politics have witnessed the emergence of two major strands of research that are related but quite distinct: an “Adaptationist” approach and a “Heritability” approach. The former explains behavior as the product of complex psychological adaptations designed by natural selection that all humans share, while the latter explains behavior as a consequence of heritable genetic differences between individuals. Importantly, neither approach excludes environmental factors from a causal role in generating behavior. Heritability approaches are more familiar to political scientists, and one well-known example is behavior genetics, as exemplified in twin study research. However, Adaptationist approaches, such as evolutionary psychology, remain theoretically underdeveloped in political science. We therefore provide a detailed outline of the theoretical framework of evolutionary psychology, and we explore its application toward the study of political behavior—an endeavor we label Evolutionary Political Science.