Observed non-procreative sexual activities include non-copulatory mounting (without insertion, or by a female, or by a younger male who does not yet produce semen), oral sex, genital stimulation, anal stimulation, interspecies mating, and acts of affection. Animals have been observed to engage in sex for social interaction bonding, exchange for significant materials, affection, mentorship pairings, sexual enjoyment, or as demonstration of social rank. Although procreation continues to be the primary explanation for sexual behavior in animals, recent observations on animal behavior have given alternative reasons for the engagement in sexual activities by animals. Non-reproductive sexual behavior consists of sexual activities animals participate in that do not lead to the reproduction of the species.
