User:Carlogp20/Homosexual behavior in animals

Primates (Jimmy)
Same-sex sociosexual behaviors have been observed in New World monkeys, Old World monkeys, and apes. Although, these behaviors are much more common in Old World monkeys than New World monkeys, and all ape genera have been observed engaging in same-sex sociosexual behaviors. Prosimians have not been observed engaging in same-sex sociosexual behavior. Same-sex mounting, for instance, has been observed in 16% of New World primate genera, in contrast, 76% of Old World monkey genera contain at least one species that has been observed in male-male mounts, and 70% of genera for female-female mounts. Same-sex mounting has been observed in all ape genera. Same-sex sociosexual behaviors likely evolved following the divergence of New World monkeys ; these behaviors are a conserved trait among Old World monkeys and apes. Among Old World monkeys, same-sex genital interactions are much more common in multi-male systems as opposed to uni-male systems.

Chimpanzees
Compared to bonobos, less research has been conducted on same-sex sociosexual behaviors in chimpanzees (Pan troglodytes). In contrast to bonobos, same-sex sociosexual behaviors are less common in Kibale chimpanzees (Pan troglodytes schweinfurthii) and primarily occur between adult males. While less frequent than in female bonobos, same-sex sociosexual behaviors between male chimpanzees occur regularly and in a variety of contexts. Female chimpanzees are much less likely to engage in same-sex sociosexual behaviors than males.

Gibbons
There is one published study of same-sex sociosexual behavior in white-handed gibbons (Hylobates lar). The authors report on observations of an adult male mounting an adolescent male. In gibbons, same-sex sociosexual behavior is likely rare.

Gorillas
Both male and female mountain gorillas (Gorilla gorilla beringei) have been observed engaging in same-sex sociosexual behaviors. Among all-male "bachelor" groups, same-sex sociosexual interactions are extremely common. Female mountain gorillas engage in same-sex sociosexual behaviors frequently as well, and coincided in prevalence in accordance with intersexual copulations as well. As opposed to conferring social status, same-sex sociosexual behaviors are likely reflective of elevated arousal in female mountain gorillas. Same-sex sociosexual behaviors are natural and common among mountain gorillas.

Orangutans
Sociosexual behaviors among orangutans (Pongo spp.) are extremely common and invoke a variety of evolutionary strategies. However, only one study of same-sex sociosexual behavior has been published. In Sumatran orangutans (Pongo abelii), same-sex sociosexual behavior has been documented among two dyads of unflanged adolescent males. Oral contact with genitals and behavior similar to male-female forced copulation between sexually mature sub-adult males were observed.