image: This image shows a frontal and right side lateral view of male face. Prior to attractiveness ratings, color photographs were scanned, and an oval mask was placed over the image to minimize the visual effect of hairstyle. view more
Credit: Journal of Evolutionary Biology
Contrary to what one might expect, facial masculinity was negatively associated with semen quality in a recent Journal of Evolutionary Biology study. As increased levels of testosterone have been demonstrated to impair sperm production, this finding may indicate a trade-off between investments in secondary sexual signaling (i.e. facial masculinity) and fertility.
Interestingly, males estimated facial images generally more attractive than females did, suggesting that males may generally overestimate the attractiveness of other men to females.
Journal
Journal of Evolutionary Biology