Beauty beyond symmetry

However, John Manning of the University of Liverpool in England cautions against over-generalization, especially by Western scientists. "Darwin thought that there were few universals of physical beauty because there was much variance in appearance and preference across human groups," Manning explained in email interview. For example, Chinese men used to prefer women with small feet. In Shakespearean England, ankles were the rage. In some African tribal cultures, men like women who insert large discs in their lips.

Indeed, "we need more cross-cultural studies to show that what is true in Westernized societies is also true in traditional groups," Manning said his 1999 article.

Aside from symmetry, males in Western cultures generally prefer females with a small jaw, a small nose, large eyes, and defined cheekbones - features often described as "baby faced", that resemble an infant's. Females, however, have a preference for males who look more mature -- generally heart-shaped, small-chinned faces with full lips and fair skin. But during menstruation, females prefer a soft-featured male to a masculine one. Indeed, researchers found that female perceptions of beauty actually change throughout the month.

When viewing profiles, both males and females prefer a face in which the forehead and jaw are in vertical alignment. Altogether, the preference for youthful and even infant-like, features, especially by menstruating women, suggest people with these features have more long-term potential as mates as well as an increased level of reproductive fitness.

Scientists have also found that the body's proportions play an important role in perceptions of beauty as well. In general, men have a preference for women with low waist-to-hip ratios (WHRs), that is, more adipose is deposited on the hips and buttocks than on the waist. Research shows that women with high WHRs (whose bodies are more tube-shaped) are more likely to suffer from health maladies, including infertility and diabetes. However, as is often the case, there are exceptions to the rule.

Psychologists at Newcastle University in England have shown that an indigenous people located in southeast Peru, who have had little contact with the Western world, actually have a preference for high WHRs. These psychologists assert that a general preference for low WHRs is a byproduct of Western culture.