Dominance judgments—important across numerous psychological domains, like attractiveness, leadership, & legal decision-making—accurately predict the likelihood with which a potential mate, ally, or rival can incapacitate their adversaries

Caton, Neil R., Lachlan M. Brown, Amy Zhao, and Barnaby Dixson. 2022. “Human Male Body Size Predicts Increased Knockout Power, Which Is Accurately Tracked by Conspecific Judgments of Male Dominance.” PsyArXiv. June 29. doi:10.31234/osf.io/3jny4

Abstract: Humans have undergone a long evolutionary history of violent agonistic exchanges, which would have placed selective pressures on greater body size and the psychophysical systems that detect them. The present work showed that greater body size in humans predicted increased knockout power during contests (Study 1a-1b: total N = 5,866; Study 2: N = 44 openweight fights). In agonistic exchanges reflective of ancestral size asymmetries, heavier combatants were 300% more likely to win against their lighter counterparts solely because they were 300% more likely to knock them out (Study 2). Greater body size afforded no other fighting performance advantages other than increased knockout power (Studies 1-2). Human dominance judgments (total N = 500 MTurkers) accurately tracked the frequency with which men (N = 516) had knocked out similar sized adversaries (Study 3). Humans were able to directly perceive a man’s knockout power solely because they were attending to cues of a man’s body size. Human dominance judgments—which are important across numerous psychological domains, including attractiveness, leadership, and legal decision-making—accurately predict the likelihood with which a potential mate, ally, or rival can incapacitate their adversaries.