These facial features can predict if someone’s into casual sex, according to scientists

They say the eyes are the window into the soul. What if we told you facial features are the key to distinguishing whether someone wants a relationship, or casual sex?

According to a new study published in interdisciplinary journal Evolution and Human Behavior, there is indeed a strong correlation between facial features and someone’s desire to engage in casual sex versus long-term relationships — at least when it comes to cis men.

For the study, University of Arizona and College of William and Mary researchers asked 103 participants to define their own “sociosexuality,” which is essentially a metric of someone’s own attitude towards casual sex. They then requested that 65 separate participants guess the sociosexuality of the initial 103 subjects strictly based off photographs of their faces.

The experiment revealed that men with high self-reported sociosexuality (read: a tendency to engage in more casual sex) tended to have more “masculine-looking” facial features, demonstrating higher testosterone levels than those with lower self-reported sociosexuality. Per Psychology Today, higher testosterone levels in men are customarily depicted via “wider faces, more space between their eyes, wider noses, thinner lips, and a stronger, larger jawline than males with less testosterone.”

The study also found that female participants made exceptionally accurate guesses regarding each male participants’ sociosexuality based off their photographs, though it was not the same in the opposite direction: Men could not accurate guess women’s sociosexuality based off their facial features.

That said, research has consistently shown that women’s faces can indicate their sociosexuality, however, concluding that sociosexuality is “less restricted” or “unrestricted” (the less restricted you are, the more likely to engage in casual sex) in men with higher levels of testosterone as well as women with higher levels of oestrogen. Women with high levels of oestrogen tend to have “smoother,” “rounder” and “softer” faces than those with lower less.

This batch of male participants may just be particularly bad at guessing, but Psychology Today presents an intriguing — yet antiquated — theory as to why women may be better suited to guess mens’ sociosexuality: Seeing as (cis) women are customarily the child-bearers and caretakers, it’s beneficial to be distinguish which partner is more likely to stay during and after pregnancy, as well as fend for and bring home food and other resources.

It is also worth noting that this study did not seem to include any transgender or non binary individuals, and is therefore a very simplified, binary and biological perspective as it exclusively analysed cis-gender participants who (seemingly) self-identified with their assigned genders.