Abstract:
Facial cues contribute to attractiveness, including shape cues such as symmetry,
averageness, and sexual dimorphism. These cues may represent cues to objective
aspects of physiological health, thereby conferring an evolutionary advantage to
individuals who find them attractive. The link between facial cues and aspects of
physiological health is therefore central to evolutionary explanations of attractiveness.
Previously, studies linking facial cues to aspects of physiological health have been
infrequent, have had mixed results, and have tended to focus on individual facial
cues in isolation. Geometric morphometric methodology (GMM) allows a bottom–up
approach to identifying shape correlates of aspects of physiological health. Here, we
apply GMM to facial shape data, producing models that successfully predict aspects
of physiological health in 272 Asian, African, and Caucasian faces – percentage body
fat (21.0% of variance explained), body mass index (BMI; 31.9%) and blood pressure
(BP; 21.3%). Models successfully predict percentage body fat and blood pressure even
when controlling for BMI, suggesting that they are not simply measuring body size.
Predicted values of BMI and BP, but not percentage body fat, correlate with health
ratings. When asked to manipulate the shape of faces along the physiological health
variable axes (as determined by the models), participants reduced predicted BMI, body
fat and (marginally) BP, suggesting that facial shape provides a valid cue to aspects of
physiological health.
