Biologists tend to look at the animal kingdom and try to categorize things in an organized fashion. But nature has a way of defying our neat little categories. Take something as common as same-sex ...

More than 59 different primate species have been observed participating in some kind of same-sex behaviors, making it extremely common.

Same-sex behavior is widespread in primates and may help strengthen social bonds and improve survival under challenging ...

Homosexual behavior in primates has a deep evolutionary basis and is more likely to occur in species that live in harsh environments, are hunted by predators or live in more complex societies, ...

Nonhuman primates like bonobos and chimpanzees might engage in same-sex sexual activities to strengthen bonds, particularly ...

Many primate species have been observed engaging in same-sex sexual behavior. A new study suggests it likely developed evolutionarily to help reduce conflict and build bonds.

A comprehensive new study has examined the prevalence of same-sex behavior in dozens of primate species.

A growing body of research suggests same-sex behavior in nonhuman primates is important to social connections.

Primates form same-sex sexual behavior alliances to gain rank and mating opportunities Male primates use same-sex bonds as ...

Almost 60 different primate species exhibit same-sex sexual behaviors.