Human Commercial Models’ Eye Colour Shows Negative Frequency-Dependent Selection

Abstract

In this study we investigated the eye colour of human commercial models registered in the UK (400 female and 400 male) and Brazil (400 female and 400 male) to test the hypothesis that model eye colour frequency was the result of negative frequency-dependent selection. The eye colours of the models were classified as: blue, brown or intermediate. Chi-square analyses of data for countries separated by sex showed that in the United Kingdom brown eyes and intermediate colours were significantly more frequent than expected in comparison to the general United Kingdom population (P<0.001). In Brazil, the most frequent eye colour brown was significantly less frequent than expected in comparison to the general Brazilian population. These results support the hypothesis that model eye colour is the result of negative frequency-dependent selection. This could be the result of people using eye colour as a marker of genetic diversity and finding rarer eye colours more attractive because of the potential advantage more genetically diverse offspring that could result from such a choice. Eye colour may be important because in comparison to many other physical traits (e.g., hair colour) it is hard to modify, hide or disguise, and it is highly polymorphic.

The effect of orthodontic treatment on smile attractiveness: a systematic review

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Perceived Effects of Orthognathic Surgery versus Orthodontic Camouflage Treatment of Convex Facial Profile Patients

“…Dental and smile esthetics might still be considerably affected in a positive way [ 35 ], although this remains to be tested. On the contrary, the impact of orthognathic surgery on facial appearance was very high, considering the variety of factors involved [ 3 , 36 , 37 ] and that this intervention alters only facial morphology. Under this prism, an impact of almost 20 points towards the positive side of the facial appearance scale is considered substantial.…”

Facial shape affects self-perceived facial attractiveness

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