Lack of Support for the Association between Facial Shape and Aggression: A Reappraisal Based on a Worldwide Population Genetics Perspective

Abstract

Antisocial and criminal behaviors are multifactorial traits whose interpretation relies on multiple disciplines. Since these interpretations may have social, moral and legal implications, a constant review of the evidence is necessary before any scientific claim is considered as truth. A recent study proposed that men with wider faces relative to facial height (fWHR) are more likely to develop unethical behaviour mediated by a psychological sense of power. This research was based on reports suggesting that sexual dimorphism and selection would be responsible for a correlation between fWHR and aggression. Here we show that 4,960 individuals from 94 modern human populations belonging to a vast array of genetic and cultural contexts do not display significant amounts of fWHR sexual dimorphism. Further analyses using populations with associated ethnographical records as well as samples of male prisoners of the Mexico City Federal Penitentiary condemned by crimes of variable level of inter-personal aggression (homicide, robbery, and minor faults) did not show significant evidence, suggesting that populations/individuals with higher levels of bellicosity, aggressive behaviour, or power-mediated behaviour display greater fWHR. Finally, a regression analysis of fWHR on individual's fitness showed no significant correlation between this facial trait and reproductive success. Overall, our results suggest that facial attributes are poor predictors of aggressive behaviour, or at least, that sexual selection was weak enough to leave a signal on patterns of between- and within-sex and population facial variation.

Social Attributions from Faces: Determinants, Consequences, Accuracy, and Functional Significance

“…This measure is not invariant with respect to image variation, because variables such as expressions, head tilt, and face orientation can change the ratio. Furthermore, it was determined that the measure is not sexually dimorphic (Kramer et al 2012, Lefevre et al 2012, and there have been several failures to replicate the finding that it predicts aggressive behavior (Deaner et al 2012, Gómez-Valdés et al 2013. The authors who initially reported the latter effect recently reported that this is only the case for men with low social status (Goetz et al 2013).…”

Modeling first impressions from highly variable facial images

“…For example, the same behavior can be interpreted as assertive or unconfident depending on the perceived dominance of an accompanying face (7), and inferences of competence based on facial cues have even been shown to predict election results (8). Nonetheless, support for the validity of these first impressions of faces is inconclusive (9)(10)(11)(12)(13)(14)(15), raising the question of why we form them so readily.…”

Reassessing the association between facial structure and baseball performance: a comment on Tsujimura & Banissy (2013)

“…A third interpretation is that associations between fWHR and performance occur by chance [7,15]. Assessing the validity of these various perspectives is possible with additional data collection and analysis.…”