A history of war: The role of inter-group conflict in sex differences in aggression

Abstract Human aggression has two important dimensions: within -group aggression and between -group aggression. Archer offers an excellent treatment of the former only. A full explanation of sex differences in aggression will fail without accounting for our history of inter-group aggression, which has deep evolutionary roots and specific psychological adaptations. The causes and consequences of inter-group aggression are dramatically different for males and females.