Heterosexual copulatory patterns in stumptail macaques (Macaca arctoides) and in other macaque species.

A comparison of the mating behavior patterns of several macaque species reveals that the mating behavior of Macaca arctoides exhibits several unique features. The laboratory groups of stumptail monkeys observed had exceptionally long single-mount copulations characterized by a large number of pelvic thrusts, a slow thrusting rate, and an unusually salient male orgasmic pattern (characterized by body rigidity followed by body spasms and a typical facial expression and vocalization). The frequency with which the copulation culminates in ejaculation is unusually high, and copulating stumptails generally manifest "tieing" in a genital lock after ejaculation.