Sociosexual Behavior Used for Tension Regulation in All Age and Sex Combinations Among Bonobos

Abstract

In biology, sexual behavior generally is investigated from the perspective of reproduction. Although the nonreproductive use of the same behavior patterns is common to many species, this use is considered of secondary importance. From an evolutionary perspective, the primary function of sexual behavior, that is, the function most directly relevant for natural selection, is its capacity of producing a zygote. But what if fertile and infertile partner combinations were to engage in sexual behavior with equal intensity and equal frequency? In such a case, it would seem that the reproductive function had decreased in relative importance. This author encountered such a situation during his studies of bonobos (Pan paniscus), and it is of particular interest because this little-known ape species, together with the chimpanzee (P. troglodytes), is the closest relative of humans.