Investigating the Relationship between the Facial Width-to-Height Ratio and Physical and Psychological Threat Potential

Abstract

Individuals with large facial width-to-height ratios (FWHR) are judged as threatening and engage in threat-related behaviours. The aim of this thesis was to identify the specific components of threat potential related to the FWHR. In study 1, participants completed measures of psychological and physical threat potential. The FWHR correlated positively with aspects of physical threat potential in men and women, and an aspect of psychological threat potential in men. Additionally, study 1 investigated the extent to which these types of threat potential differentially predict aggression. In men only, psychological threat potential predicted non-costly aggression, and physical threat potential predicted costly aggression. In study 2, participants made inferences about the threat potential of participants from study 1. Results demonstrated an ability to infer threat potential from the face, and sex differences related to the definition of aggressiveness. Together, these findings demonstrate that the FWHR conveys two forms of threat potential in men, which differentially predict aggression.