- If a man has a "masculine" face, he may be more inclined to cheat, according to new research.
- When participants were shown photos of men with features like a strong jaw and thinner lips, they tended to label them as more likely to cheat.
- The ratings given by participants matched up with self-reported behaviors from the men in the photos — how much they cheated and "poached" other men's partners.
- The same was not found for photos of women.
- Previous research has found women may be able to tell if a man is a cheater from his voice too.
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Finding out your partner has been seeing someone else behind your back is devastating, and often it can feel like there were no signs it would happen. But according to new research, if a man has a "masculine" face, he may be more inclined to cheat.
The study, published in the journal Royal Society Open Science, found that men with features like a strong jaw and thinner lips were more likely to stray from their partners, and even steal them from other men.
Researchers asked 299 men and 452 women to look at photos of men and rate on a scale of one to 10 how likely they might be to cheat. The men photographed were also asked to rate their own "poaching" behaviors — how much they stole other people's partners.
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It turned out that the ratings from the men and women matched up with what the men in the photographs said about themselves.
"Therefore, perceived unfaithfulness may indeed contain some kernel of trust in male faces," said the researchers.
"The small effects, however, also indicate that we should not rely on our first impressions to make diagnostic judgments of unfaithfulness in everyday situations."
In other words, you shouldn't judge someone from their jawline alone.
When the same test was done on women's faces, neither their "poaching" or cheating rating could be determined by looking at their faces, suggesting it's just male characteristics that are a giveaway.
Other previous research has shown there may be some truth to presuming someone is "the type" to cheat when you meet them as well. For instance, one study published in the journal Evolutionary Psychology found that someone's voice could indicate whether they'll be faithful to you or not.
By hearing ten brief recordings of men and women's voices, the participants were able to judge actual cheaters as more likely to have cheated — and women were better at it than the men.
One theory is that women perceive deeper voices as more unfaithful, which is backed up by research from 2011, but the team manipulated the voices in this study to try and account for this.
Another possible reason is that the recordings sounded a little bit like previous partners who had cheated on the participants, but pinpointing exactly what it is that made them stand out in this way is unclear.
"These findings expand upon the idea that the human voice may be of value as a cheater detection tool," the researchers wrote. "Very thin slices of vocal information are all that is needed to make certain assessments about others."
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