This text examines the emergence of a group of practitioners who advocate "a more biologically oriented" approach to their social science's subject matter. This contention directly challenges the basic tenets underlying the long-dominant standard social science model. Advocates of this model believe that human behavior is not meaningfully influenced by our evolutionary background, but is instead learned. Consequently, the possibility that our behavior is genetically influenced is often ignored. The advocates of a "more biologically oriented" approach are attempting, in effect, an intellectual revolution. Part I of this volume examines, discipline by discipline, the history of the evolutionary thrust, leading figures and key literature, the degree of acceptance (or rejection) within each discipline, and the likely future prospects. Part II discusses the biobehavioral approach on a geographic basis, with experts assessing the status of evolutionary behavioural science across a number of countries and regions.