Primate Sex Pheromones of Vaginal Origin

Abstract

EVIDENCE from field^1–7 and laboratory^8–14 studies suggests that the males of several primate species are aware of the endocrine condition of females. While both motor responses and the role of visual cues have received attention, the possibility that olfaction might communicate information about sexual status between consorts has only recently been investigated in microsomatic, higher primates^15‐19. Adult male rhesus monkeys will not regularly press a lever for access to ovariectomized partners unless the partners are oestrogenized²⁰. Further, if small amounts of oestradiol are administered directly into the vaginas of ovariectomized females at a time when their male partners have been made anosmic, the males continue to respond to them as though they are anhormonal. Males, however, will begin pressing levers for access to these females as soon as their olfactory acuity is restored. This fact suggested that oestrogen-treated females produce an olfactory pheromone capable of stimulating male sexual interest²¹. To explore possible sites of production of male-attractant pheromones, we have studied the effects on male behaviour of transferring vaginal secretions between donor and recipient female partners.