Do observers infer aggressive character traits from facial shape?

Research suggests that wide facial shape relative to facial height (fWHR) may serve as a cue to social threat in men by signalling aggression and dominance. In the present study, we examined whether observers rely on facial shape itself rather than on emotional facial expression when they infer character traits. In two experiments participants viewed photographs of male faces in which either expressions were masked (Experiment 1), or facial shape was manipulated so that facial width was no longer recognisable (Experiment 2). Participants completed two-alternative forced-choice tasks in which they indicated whether the photographs depicted aggressive (Experiment 1) or powerful (Experiment 2) characters, or their opposites. Results showed that participants inferred the target traits above chance and continued to identify aggressive-dominant traits above chance even when facial expressions were masked. However, facial width was not correlated with the accuracy of participants' character assignments and was rarely mentioned as an informative cue. We conclude that observers may have relied on other shape-related features, some of which may covary with facial width, such as chin angularity. Overall, and contrary to our expectations, participants did use face shape in addition to expression cues to infer aggressiveness and dominance, albeit to a limited extent.