CROSS-SPECIES COMPARISONS: MASTURBATION
Some form of self-stimulation has been reported in a variety of nonhuman species (Beach, 1976; Chevalier-Skolnikoff, 1974; Rowell, 1972). But not all autogenital stimulation qualifies as real masturbation in the framework of Beach's model since some of these behaviors are not truly appetitive or consummatory. For example, males of many species lick or manipulate their genitals at various times, particularly immediately after mating; these responses then are grooming responses, not sexual responses.
True masturbatory behavior has been observed in several species of mammals. Males typically rub the penis against some object. Monkeys have been observed to use their hands and, because of their body flexibility, can even orally stimulate themselves. Captive female monkeys have been observed to insert a foreign object into the vaginal opening and to move it rhythmically. Many of us have probably observed some kind of self-stimulative behavior in domesticated animals or in zoos. It was once thought that masturbatory behavior occurred only among captive animals, but we now know that it occurs also among feral animals (Beach, 1976; Carpenter, 1942). Masturbation does appear, however, to be more common among captive animals than among those in the wild. Captive male chimpanzees often masturbate, even in the presence of receptive females, a phenomenon Beach (1976) suggests may be due, in part, to the boredom of captivity.
Thus, there are striking similarities among the masturbatory behaviors of humans and the lower organisms, especially the primates. Beach feels that the similarities are so consistent as to conclude that masturbatory patterns of behavior for men and male primates is probably traceable to their shared mammalian-primate origins. He states:
The self-stimulatory activities of male monkeys and apes are so similar to autogenital behavior in human males that we are justified in provisionally defining male masturbation as a basic primate trait. As far as females are concerned, the evidence is less convincing, but sex differences in frequency seem common to humans and other primates and planned observation of nonhuman species is needed before any conclusion is justified.
Men's Health-Erectile Dysfunction