When Mike Napoli got up to bat in Game 6 of the World Series, my first thought was, "Oh my goodness, that beard is awful." But after the Red Sox's first baseman laid off a few bad pitches, I started liking the hair on his chin.
All that got me thinking about beards.
Sometime during evolution women lost their facial hair. This strong difference between the sexes implies that facial furriness, or the lack thereof, has played a role in how we picked our partners, at least at one point in human history.
But tastes and preferences are complicated issues. They vary over time, cultures and geography. And they change much faster than evolution.
So what does science say about a modern man's beard? Does facial hair actually make men more attractive? Perhaps, but it appears to depend on the length and density.
The scientific evidence on the topic is scant and mixed. Researchers in the '80s and '90s resorted to fake beards or painted beard-like patterns on people's faces.
But a study published in May started to clear up the confusion. Psychologists at the University of New South Wales in Sydney found that women slightly preferred a heavy, 10-day stubble — something like George Michael's look during the Faith years — compared to a full beard or a clean-shaven face.
The team showed 528 men and women pictures of 10 men, each with four variations of facial hair: clean-shaven, light stubble (like Don Johnson rocked in Miami Vice), heavy stubble and a full beard (something better groomed than Napoli's overgrown chops but still complete coverage). "Self-identified homosexual and asexual participants were excluded, as were female participants that were pregnant," the researchers wrote.
The effect was subtle. On average, women found the thick, 10-day stubble to be most attractive. The smooth shave came in a close second, and the light, five-day stubble was at the bottom of the list. In contrast, men equally preferred a full beard, heavy stubble and a clean-shaven face, the researchers wrote in the Journal of Evolution and Human Behavior.
"Beards are signals of several things," says Daniel Kruger, a psychologist at the University of Michigan, who wasn't involved in the study. "Beards develop reliably as men enter adulthood. So they signal sexual maturity — that you can maintain a high level of testosterone."
A fuzzy, 5 o'clock shadow, on the other hand, could be perceived in some cultures as patchy and unhealthy, Kruger tells Shots. "People with really poor nutrition or who are addicted to drugs, their hair often falls out," he says. "You often see a relationship between the appearance of your hair and your health."
Nevertheless, Kruger cautions that the recent study on beards was limited. All the hair models were of European descent, and the effect was small. "Not every human population has really heavy facial hair," Kruger says. "So the study needs to be repeated with a wider selection of men and across cultures."
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