There are several factors that go into why people are attracted to each other, but researchers have uncovered one that most women have probably never thought of: They might be into men who look like their brother.
That’s the conclusion from a new study published in the July 2017 issue of the journal Evolution & Human Behavior. For the study, researchers asked participants to look at pictures of men and group them according to the guys who looked the most similar. The photos included famous men as well as people the participants had never seen before. But the nonfamous pictures actually included pictures of other women’s brothers and partners, which were sent in by volunteers.
During the study, participants were given a sheet of paper with a woman’s brother in one column and four men (including the woman’s partner) in the other. Participants were then asked which man in the group of guys looked most like the man in the first column.
While study participants didn’t match up the woman’s brother with her significant other every time or even most of the time, they did it enough — 27 percent of the time — that it was statistically significant. (Statistically speaking, the two men should be partnered up 25 percent of the time.) The researchers concluded that this is the “first empirical data that heterosexual women select partners who resemble their brothers.”
Lead researcher Tamsin Saxton, an associate professor of psychology at Northumbria University in England, tells Yahoo Beauty that she’s not entirely sure why this happens, but there are a few theories out there. One is the familiarity aspect — meaning, we’re drawn to people and things that are familiar to us. “In addition, it seems to be biologically beneficial, in terms of numbers of offspring, to reproduce with someone who’s neither too closely nor too distantly related,” Saxton says. “So a subtle resemblance to family members might indicate someone who would be biologically well-matched as a reproductive partner.”
David Moskowitz, a research assistant professor at the Institute for Sexual and Gender Minority Health and Wellbeing at Northwestern University who did not work on the study, agrees. “While it’s tempting to believe that opposites attract, in reality it is the safety and predictability of similarity that usually leads to the most successful and longest-lasting relationships,” he tells Yahoo Beauty.
Before you give your partner the side-eye, know this: Saxton says the effect is subtle and isn’t true of every woman — some had partners that didn’t resemble their brothers at all.
Moskowitz also points out that more research is needed before people can definitively say that this is a thing. “Yes, they found ‘significant evidence’ to suggest that women tend to select partners that look like their brothers,” he says. “However, replicative studies are necessary that use different, more diverse pictures, considering these findings are a mere two percentage points above chance.”
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