Homosexuality can be confusing to those who believe that humans have been put on the earth for one thing - reproduction. Some people who don't understand might ask "why" or "how" homosexuality fits in with the human instinct of survival.
Scientists from the University of Portsmouth in England have a contentious new theory, according to Huffington Post. Researchers suggest that homosexuality developed in humans (and other primates) as a way to form social bonds.
"From an evolutionary perspective we tend to think of sexual behavior as a means to an end for reproduction," Diana Fleischman, an evolutionary psychologist at the university and study author, told University of Portsmouth News. "However, because sexual behavior is intimate and pleasurable, it is also used in many species, including non-human primates, to help form and maintain social bonds. We can all see this in romantic couples who bond by engaging in sexual behavior even when reproduction is not possible."
The study included 92 women who were asked a series of statements such as, "The idea of kissing a person of the same sex is sexually arousing to me," according to Huffington Post, or, "If someone of the same sex made a pass at me I would be disgusted."
Progesterone levels in the woman's saliva were tested and researchers discovered that women with higher progesterone levels were more open to homosexual activity. Progesterone is linked to social bonding, according to Huffington Post, and sexual encounters - heterosexual or homosexual - are a form of bonding.
Progesterone is produced in the ovaries of women and in the adrenal glands of men, according to University of Portsmouth News. Progesterone levels rise during friendly interactions and, for women, peak after ovulation (when pregnancy risks are reduced).
The 59 men that participated in the study were asked to complete word puzzles from three categories: "friendship (for instance, 'fr...ds' becomes 'friends'), sex ('br...ts' becomes 'breasts'), or neutral ('sq.ar.' becomes 'square'), Huffington Post explained.
Researchers found that those that completed the friendship puzzles were 26 percent more likely to be open-minded about a homosexual encounter than the men in the other two groups. That is, men who were made to think about friendships and bonding were more receptive to the idea of sexual behavior - heterosexual or homosexual - based on progesterone levels, Fleischman explained, according to The Huffington Post.
"The results of our study are compelling because using two very different methods; they arrived at the same conclusion," Fleischman said, according to University of Portsmouth News. "Women were more likely to be motivated to think about homosexual sex when their levels of progesterone were higher. Compared to a control group, men's homoerotic motivation was not increased by priming them with sex but thinking about friendship and bonding caused a measurable change in their attitude to the idea of having sex with other men."
"It's very complex, but it's clear there's a continuum between affection and sexuality, and ... the ability to engage sexually with those of the same sex or the opposite sex is common," Fleischman said, according to Huffington Post. "In humans, much, if not most of same-sex sexual behavior occurs in those who don't identify as homosexual."
Fleischman's study was published Nov. 25 in the journal Archives of Sexual Behavior.
