Sexual preference for traits commonly associated with ‘feminine’ women or ‘manly’ men is a product of living in an urban environment, not of evolution, according to findings by Brunel University and the University of Bristol.
In a joint study, researchers gathered evidence which indicated that the preference for masculine traits in male faces, such as wide chins and large eyebrows, and femininity in female faces, for example, large lips and small noses, was ‘strongly linked’ to living in a developed society, and was not seen outside of it.
The findings challenge the common belief that evolution has directed the human preference for particular sexual traits.
Researchers surveyed twelve populations varying in their economic development located around the world and preferences for exaggerated sex specific traits were found only in highly developed environments.
962 participants were shown sets of opposite-sex photographs and asked to report which was most attractive and which was most aggressive. Each set of photographs represented the five ethnic groups recruited to the study.
The photos were digitally enhanced to varying degrees to accentuate male traits in the photographs of men and typically female traits in the photographs of women. For example, softer lips, bigger eyes and rounder faces.
Only the participants living in developed towns and cities showed a preference for make and female traits.
It was those same urban participants that identified aggression in male faces.
The findings challenge the belief that sexual preferences for traits commonly associated with males and females is linked to evolution.
‘This data challenge the theory that exaggerated sex specific traits were important for social and sexual selection in ancestral environments’ Isabel M. L. Scott.
The research team suggest that the results might be due to those members of an urban environment coming across a greater number of individuals than those in less developed societies, providing more opportunity to develop skills to interpret nuances in behaviour, and an increase in motive.
‘The authors speculate that highly developed environments with large, dense populations may expose individuals to more unfamiliar faces, perhaps providing the opportunity – and motive – to discern subtle relationships between facial traits and behaviour.’
‘Human preferences for sexually dimorphic faces may be evolutionarily novel’ by Isabel M. L. Scott.
creative commons licensed (BY-NC-ND) flickr photo by Alexander Rentsch: http://flickr.com/photos/captain_die/14296352514