The notion that women find “bad boys” sexually attractive gets reinforcement from a new study published in Emotion showing that happiness is not a sexually attractive emotion for men to display.

The University of British Columbia study found dramatic gender differences in how men and women rank the sexual attractiveness of commonly displayed emotions, including happiness, pride, and shame. “This study finds that men and women respond very differently to displays of emotion, including smiles,” said Jessica Tracy, co-author of the study. She believes the study is the first to measure the attractiveness of smiles.

One-thousand adults participated in the study, rating the sexual attractiveness of hundreds of images of the opposite sex engaged in displays of happiness (broad smiles), pride (raised heads, puffed-up chests) and shame (lowered heads, averted eyes).

The results showed that women were least attracted to smiling, happy men, preferring those who looked proud and powerful or moody and ashamed. In contrast, male participants were most sexually attracted to women who looked happy, and least attracted to women who appeared proud and confident.

Co-researcher Alec Beall said it was important to remember that the study ranked sexual attractiveness, not suitability as a long-term partner. “We were not asking participants if they thought these targets would make a good boyfriend or wife – we wanted their gut reactions on carnal, sexual attraction.”

Discussing the findings, the researchers suggest that females are attracted to male displays of pride (emphasizing upper body size and muscularity) because they imply status, competence and an ability to provide for a partner and offspring.

As far as the unsexy smile goes, Tracy says that the findings can be understood in the contexts of evolutionary psychology and socio-cultural gender norms. For example, past research has associated smiling with a lack of dominance, which is consistent with traditional gender norms of the “submissive and vulnerable” woman, but inconsistent with “strong, silent” man. “Previous research has also suggested that happiness is a particularly feminine-appearing expression,” Beall adds.

Interestingly, they say the attractiveness of expressions of shame may be linked to appeasement behaviors, which elicit trust in others. This may explain shame’s surprising sexiness to both genders; given that both men and women prefer a partner they can trust.

The researchers are mulling future studies that would explore the relationship between emotions and sexual attractiveness among homosexuals and non-Western cultures.

Related:

Masculinity trumps intelligence for ovulating women

Experiments reveal aggression to be a “manhood-restoring tactic”

Why are the happiest places also suicide hotspots?

Penile presence makes for abominable affairs