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We are seeing a resurgence of facial hair among political extremists, occupational nonconformists, and others. These changes are most often discussed as a fashion trend. But shaving tools are recent and the beard has always been a sexual signal.
Facial hair is often discussed as something of an anomaly because most people shave some, or all, of their facial hair. In the distant past, people who wanted to remove hair had to pull it out. This would have been painful and impractical for beards.
Throughout most of our history as a species, men would have presented with full facial hair, at least for those populations where males are heavily bearded. The first shaving tools emerged about five thousand years ago when they were made of copper. (Ouch!)
Why did men have beards? Why are so many men shaving them today?
Beards as a Sexually-Selected Trait
Facial hair might be thought of as a covering for keeping the face warm. This is not credible for three good reasons. First, women do not have them. Neither do children, who are most vulnerable to cold temperatures given their high surface area relative to volume. Second, if you walk upright, the best place for an insulating layer is the top of the head where our scalp hair grows. Thicker scalp hair would yield a bigger thermal boost than hair growing lower down on the face. Third, facial hair appears after childhood—at puberty—when thermal vulnerability has passed.
Facial hair develops under the influence of increasing testosterone at puberty. If a bodily feature emerges reliably during puberty, and if it plays a social signaling role, then it is referred to as a sexually-selected trait. Examples include the curvaceous body shape of women and male facial hair.
If the beard is to be considered a sexually selected trait, then it must send a signal. There are two types of sexually selected signals. One attracts the opposite sex. The other intimidates rivals.
One sexually-selected trait that both intimidates rivals and attracts females is a large body size. But human beards can also be intimidating. That may be why they are popular in many male-dominated societies, and why philosophers, sages, and academics grow beards. What about sexual attraction?
Are Beards Sexually Attractive?
Our perceptions of facial hair are distorted by our social expectations. In developed countries, wearers of beards are often low-ranked persons, including the homeless and manual workers, who lack the appearance codes of white-collar workers.
Beards may thus send conflicting signals. When women are asked the question overtly many say that beards are not attractive. On the other hand, when bearded men shaved their facial hair in stages, the more hair they lost, the less attractive they became.
Even more important, perhaps, women rate bearded faces as higher on virility, dominance, parenting ability, creativity, health, and other qualities known to be indicative of mate value. The only real negative was that bearded men were perceived as less trustworthy.
So, whatever misgivings women might have about beards, the best evidence available, found that facial hair increases a man's sexual attractiveness. If so, then why would any man interested in dating ever shave?
Shaving as a Signal of Trustworthiness
Apart from some negative connotations about beardedness being related to homelessness and other hated out-groups, such as terrorists, researchers found that clean-shaven men are more likely to be perceived as honest and trustworthy.
Trust may be a key element in a sexual relationship, particularly for women. This is because a woman who becomes pregnant and gives birth is typically making a huge lifelong investment, whereas the father may shirk parental responsibility.
I wondered whether women would prefer clean-shaven partners during historical periods when men were more likely to defect from parental duty, as measured by the proportion of births outside of wedlock. This hypothesis was supported. Interestingly, the most important element was a clean-shaven upper lip.
The region around the mouth is a critical source of information about emotional states. Such information, along with changes in the eyes and nose, reveals a liar's true emotional state that can be inconsistent with what they are saying. The mustache is the only segment of facial hair that obscures such nonverbal leakage.
Hence the widespread perception that clean-shaven people are more honest. Moreover, one sign of lying is an attempt to conceal the face, most often by covering the mouth with a hand.
Putting these pieces together, it makes sense that women preferred men having clean-shaven upper lips during historical times when births outside wedlock were high. At such times, women avoided men whose facial hair could be a barrier to revealing their true intentions in a short-term seduction effort.
Facebook image: Jelena Zelen/Shutterstock
