Wilson and Daly's Young Male Syndrome thesis seeks to explain why young men are disproportionally involved in both violence and non-violent activities entailing a risk of injury or death. One interpretation of this thesis, which we term the Crazy Bastard Hypothesis, holds that the correlation between violence and other forms of physical risk-taking occurs because the latter behaviors inherently index the general propensity to take risks with one's life. In violent conflicts, individuals who are indifferent to the prospect of injury or death constitute dangerous adversaries, and valuable allies. Voluntary physical risk-taking may thus serve a signaling function such that risk-prone individuals are perceived as more formidable than risk-averse individuals. Prior work has demonstrated that relative formidability is represented using the dimensions of conceptualized size and strength, providing an avenue for testing the Crazy Bastard Hypothesis. In multiple studies conducted in two disparate societies, we demonstrate that physically risk-prone men are envisioned to be larger, stronger, and more violent than risk-averse men. A separate study reveals that such conceptualizations are unlikely to reflect actual correlations between size/strength and physical risk-proneness, and are instead plausibly interpreted as revealing the contribution of observed physical risk-proneness to assessments of relative formidability. © 2014 Elsevier Inc.