You Can Judge A Book By A Cover (If It's Male)

Apparently, you can read books by their covers — or, at least, you can read men's intelligence by their faces. According to a recent study published in the journal PLoS One, people can accurately detect the level of a man's intelligence by observing his face. On the other hand, as the study's results demonstrate, measuring a woman's intelligence by observing her face is much, much harder.

The study's authors, which are Karel Keisner, Veronika Chvátalová, and Jaroslav Flegr, from Charles University in Prague, structured this experiment by organizing participants into two independent groups: one group of 80 biology students from the Faculty of Science (40 men and 40 women) who had their IQs tested and faces photographed, and another group of 160 students from the University's Faculty of Humanities.

The 160 raters (75 men and 85 women) were each shown the 80 photographs in random order and were asked to rate the faces for either intelligence or attractiveness. Of those raters, 43 women and 42 men judged photos for intelligence, and 42 women and 33 men judged them for attractiveness, using a scale of 1 to 7 (1 being the highest score, 7 being the lowest possible score).

What did the study authors find?

• A correlation between perceived attractiveness and perceived intelligence — and it was much stronger for women's photos than men's photos.
• Men in the photos with a higher IQ tended to be perceived as more intelligent much more than women in the photos who also had higher IQ scores.
• There was no correlation between IQ and perceived attractiveness.

Furthermore, the scientists also measured the facial shapes of the photographs to determine if facial shape had a correlation with IQ, but they found none.

Why the difference in determining male vs. female intelligence? According to the study, the scientists believe that cues of higher intelligence tend to be visible only in men's faces "due to some genetic and developmental association to sex steroid hormonal agents during puberty."

However, there's another possible explanation...

Women are pervasively judged according to their attractiveness. The strong halo effect of attractiveness may thus prevent an accurate assessment of the intelligence of women.