Abstract
Biological accounts of facial attractiveness have typically presented preferences for attractive faces as arising from adaptations for mate choice or as by-products of general sensory bias (Little et al., 2011; Rhodes, 2006). Both frameworks place the mechanisms responsible for the preferences for attractive faces in the evolution of the human lineage, leaving open the possibility that non-human primates might also share such mechanisms, and therefore show a form of sensitivity to attractive faces. If human ratings of attractiveness are the product of mechanisms shared among primates, they might also predict visual face preferences in monkeys. We sought to determine whether explicit ratings of attractiveness by human judges would predict implicit visual preferences in other humans and also in non-human primates, and if they do, whether such preferences would extend beyond conspecific faces. Human and rhesus macaque faces were rated for attractiveness by human judges, and paired in accord with the attractiveness ratings (i.e., attractive faces paired with unattractive faces). Face pairs were shown to human and rhesus macaque participants while their eye-movements were recorded. We found that human ratings of attractiveness predicted implicit preferences in non-human primates. However, we also found a species-specific effect of face attractiveness in which humans showed a visual preference for human faces (but not macaque faces) rated as attractive, and macaques displayed a visual preference for macaque faces (but not human faces) rated as attractive (Figure 1). The findings suggest that attentional bias toward attractive faces is not the result of an exclusive operation of mate choice adaptation mechanisms, nor a reflection of the sole influence of a general sensory bias, but rather it reflects their interaction. The influence of a general sensory bias may be modulated by the categorization of a face as conspecific or heterospecific, leading to species-specific preference for attractive faces.
Meeting abstract presented at VSS 2018