During certain developmental periods like puberty, testosterone plays a role in forming our adult sexual desires and researchers believe it also affects our facial width-to-height ratio (FWHR).
“There has been a growth in research examining how facial characteristics relate to behaviors associated with testosterone, mainly because it is suspected that testosterone helps shape cranio-facial structure,” Steven Arnocky, associate professor of psychology at Nipissing and lead author of the study, told Seeker. “Most of this work has focused on male-typical traits. But because testosterone has been associated with sexual motivation in both men and women, we found it particularly interesting.”
Previous research has connected other human behavior with face shape and size. A University of Glasgow study found square-faced men are more likely to be aggressive, dominant, and unethical and are considered more attractive as temporary sexual partners than men with longer faces.
“In terms of aggression, some research shows that pro hockey players with higher FWHR's get more penalty minutes,” Arnocky said.
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Arnocky and his team conducted two different studies that relate sexual behavior to face shape. The first asked 145 undergraduate students questions about their interpersonal behavior and sex-drive. The second study was an extension of the first and asked 314 undergrads about their sexual orientation, their chances of considering infidelity and how comfortable they are with casual sex that doesn’t include love.
The results showed that FWHR can be used to predict a measure of sexuality in both genders. Men and women with a high FWHR — square and wide faces — reported a greater sex drive than those with longer faces. This was true for both individuals in relationships as well single people.
“The first study consisted only of men and women who were in relationships and the effect remained, suggesting that FWHR also predicts sex-drive within relationships,” Arnocky said.
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In addition to a higher sex drive, the study also found that men with square, wide faces are more comfortable with casual sex and are more likely to consider cheating on their partners. This supports previous research published in the journal Personality and Individual Differences showing men who have a larger FWHR are more willing to cheat in a contest and tend to exhibit a higher fearless dominance than men with longer faces. Thus far, the connection has only been found in men, not women.
Arnocky’s findings indicate the importance of using facial characteristics to understand more about our sexual motivations and will help with future studies that look at how different evolutionary pressures have influenced human mating.
"These findings,” Arnocky said, “extend the field’s understanding of FWHR as a morphological index of psychology and behavior in men and women."
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