Human sexuality

Sexuality in humans is conditioned by a combination of innate preferences and social and cultural factors. Different cultures have viewed sexuality differently throughout history. Research into the causes and nature of human sexual variation is ongoing. In Western societies, people may categorize sexual behaviors and preferences into sexual orientations or identities, such as heterosexual, homosexual, bisexual, and asexual. However, there is no evidence to support the existence of distinct categories of sexual behavior.

Sexuality in other primates

Homosexual and bisexual behavior has been observed in numerous primate species, including bonobos, orangutans, macaques, and gorillas. Homosexual and heterosexual acts can serve a variety of functions, including social bonding, welcoming newcomers, and resolving tension.