NEOCORTEX SIZE, SOCIAL SKILLS AND MATING SUCCESS IN PRIMATES

The social brain hypothesis predicts that species with relatively larg er neocortices should exhibit more complex social strategies than thos e with smaller neocortices. We test this pre diction using data on the correlation between male rank and mating success for polygamous prima tes. This correlation is negatively related to neocortex size, as woul d be predicted if males of species with large neocortices are more eff ective at exploiting social opportunities to undermine the dominant ma le's power-based monopolisation of peri-ovulatory females than are tho se with smaller neocortices. This effect is shown to be independent of the influence of male cohort size.