Scientists in Australia have discovered that the growing popularity of beards is likely to make all bearded men less attractive in the eyes of both women and men, according to Channel 4 TV in the United Kingdom.
Published in the Royal Society journal Biology Letters, the study used social media to examine beards in terms of evolutionary genetics – i.e. whether the trends in facial hair, and the response to them, are subject to the same laws of attraction and evolution as other genetic traits.
Researchers at the University of New South Wales photographed men at four stages of facial hair growth: clean shaven, five days of growth, 10 days of growth, and a full beard of at least four weeks growth.
The photos were then posted online in various groupings and both men and women were asked to rate them.
What the researchers found was that the responses were strongly influenced by the contexts in which the images were displayed. For instance, when beards appeared within a series of clean-shaven faces, they were rated more attractive – and vice versa.
"When full beards were rare or when the four levels of beardedness were evenly distributed, full beards enjoyed significantly higher attractiveness than when full beards were common," said Professor Rob Brooks.
To put it simply, beards are attractive when there aren't too many of them around. They are a lot less attractive when they are commonplace.
The phenomenon is known as "negative frequency dependency" (NFD), and is not uncommon in evolutionary biology. Among guppies for example, the male fish can develop rare colored spots, making them less likely to be preyed upon, and more likely to get a mate. But when this pattern spreads and becomes common, the effect is significantly diluted.
But men with fashionable stubble need not worry. The study concluded that five- or 10-day- old facial hair did not have much of a bearing on levels of attractiveness.