It turns out that when it comes to sexual fluidity, more women tend to change between heterosexuality, homosexuality and bisexuality compared to men. As in, women can more easily switch between male and female partners. And according to evolutionary psychologist Dr. Satoshi Kanazawa, this is all a result of evolution.
While that may sound a little far-fetched, Dr. Kanazawa’s reasoning in Biological Reviews is that women are more sexually fluid than men as a result of historically common polygamous marriages, where one man would have multiple wives. These women would engage in sex amongst each other in order to “reduce conflict and tension among co-wives in polygynous marriages.” Basically, engaging in sexual relationships with the other women helped to make them friends, rather than competitors. Sound like Big Love yet?
Kanazawa formulated his proposal by tracking the self-identified sexual feelings of American young people over 10 years. After measuring sexuality through four waves of interviews, Kanazawa found that women were less likely to define themselves as strictly homosexual, bisexual or heterosexual. According to Glamour UK, Dr. Kanazawa commented, “Rather than being straight or gay, to whom women are attracted may depend largely on the particular partner, their reproductive status, and other circumstances.”
Another aspect of the theory is that, since women left their homes in order to marry while men stayed in their childhood community, it was more beneficial for women to develop alliances and relationships with other wives as they adjusted to a wholly unfamiliar environment. Long story short, sexual fluidity was a coping mechanism for women back in the day.
According to Kanazawa, his theory that female sexual fluidity stemming from polygamous marriages could also explain male arousal to lesbian sex as well as menstrual cycles between females synchronizing over time. For now, we’ll just have to see whether Kanazawa’s theory becomes accepted or not. It could really change the way we perceive sexuality.