culled from:http://www.ozy.com
A recent study in the Journal of Evolutionary Biology
bolstered earlier findings that hotter dudes have higher-quality sperm;
that the little guys moved faster, and more of them looked physically
normal, making it more likely that they would fertilize an egg. But
here’s a twist: Men with masculine features, namely wide-set faces, had poor semen quality.
Studies have shown that women tend to prefer men with attractive faces —
symmetrical faces with clear skin, for example — since they might
signal health and intelligence, characteristics that they can pass on to
their children. But few studies have investigated whether men’s facial
attractiveness could also indicate their fertility.
To find out, scientists from the University of
Valencia in Spain, the University of Western Australia and other
institutions asked college dudes to get down and dirty, analyzing
ejaculated semen from 50 white University of Valencia students. They
peered at the samples through a microscope to calculate the percentage
of motile and normal-looking sperm in each, and took frontal and profile
photos of each volunteer.
Manly-looking men tend to have more sex, so even if their sperm isn’t top-notch, they still stand a good chance of impregnating their mates.
They also recruited about 200 students from the
University of Valencia and the Universidad del Norte in Colombia — all
heterosexual — to evaluate the photos. They asked the female students
from each group to rank the men’s attractiveness as possible long-term
partners, and the men to rate how attractive the sperm donors might
appear to a straight woman.
The scientists then rated the masculinity of each
donor’s face, measuring characteristics that earlier studies had found
differ strikingly in men versus women — like cheekbone width, which is
larger in men and has been shown to correlate with testosterone levels
and testosterone-linked traits, like aggressiveness and physical
strength.
Sure enough, men rated as more attractive, generally, tended to have healthier semen. But cheekbone width was negatively
associated with sperm quality. In other words, “men with more masculine
(i.e., wider) faces tend to have poorer-quality semen than more
feminine-faced men,” the study authors wrote.
Why? Maybe because the heightened testosterone
levels that contribute to masculine features can impair sperm
production. Or there may be a trade-off between how much sex men have
and their sperm quality. The study notes that some researchers theorize
that manly-looking men tend to have more sex, so even if their sperm
isn’t top-notch, they still stand a good chance of impregnating their
mates and passing on their genes. But less masculine guys — even if
they’re generally nice to look at — hit it less and need to capitalize
on every coital encounter.
Of course, the researchers note that they need to
conduct further studies to determine whether their findings apply to
other cultural groups, too. But they still suggest that brute and brawn
don’t always win the race.
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