“…These measures included others' ratings of facial dominance and of facial attractiveness; both of these variables positively predict ability to compete for resources in modern organisations (Fruhen, Watkins, & Jones, 2015), and the former is a positive predictor of male strength (Toscano, Schubert, & Sell, 2014). Facial variables also included objectively-measured facial shape masculinity (Penton-Voak et al, 2001), which, like muscularity, is believed to increase with developmental testosterone exposure and is correlated with circulating testosterone levels in adult males exposed to competitive stimuli (Pound, Penton-Voak, & Surridge, 2009). Moreover, we included facial width-to-height ratio (fWHR), a variable which has recently been shown to be associated with a range of related behavioural traits in males (for a review see Hodges-Simeon, Hanson Sobraske, Samore, Gurven, & Gaulin, 2016).…”