Now, according to a new study, published in Archives of Sexual Behavior, by researchers from University of Portsmouth, England, homosexual behaviour may be helping us bond with people of the same sex.
The study, conducted on mostly heterosexual men and women, found that people with higher levels of the hormone progesterone, present in both sexes and linked to social bonding or affiliation, are more likely to have homoerotic thoughts. Progesterone, produced mainly in the ovaries of women and in the adrenal glands of men, is known to contribute to the formation of social bonds, which have many adaptive benefits for humans. For instance, this hormone is one of the main ones responsible for caring or friendly behaviour, and levels rise when people have close and friendly interactions.
The researchers claim that there is a societal and evolutionary benefit in forming same-sex alliances. They write in the journal: ‘The frequency of homoerotic behaviour among individuals who do not identify as having an exclusively homosexual sexual orientation suggests that such behaviour potentially has adaptive value. Here, we define homoerotic behaviour as intimate erotic contact between members of the same sex and affiliation as the motivation to make and maintain social bonds. Among both male and female nonhuman primates, affiliation is one of the main drivers of homoerotic behaviour. Correspondingly, in humans, both across cultures and across historical periods, homoerotic behaviour appears to play a role in promoting social bonds… These findings constitute the first experimental support for the affiliation account of the evolution of homoerotic motivation in humans.’