Copulatory Vocalizations of Chacma Baboons (Papio ursinus), Gibbons (Hylobates hoolock), and Humans

The copulatory vocalizations of female baboons (Papio ursinus) are more complex than those of female gibbons (Hylobates hoolock) or human females. Adult males of all these species begin calling later than the female, but subordinate baboon males do not call. Copulatory vocalizations may serve to mutually stimulate the mating partners or to incite male competition.