Sell, Hone, and Pound (2012) examined the importance of physical strength in shaping male psychology. Aggression and violence are quite effective ways of winning a conflict in the competition for resources between males, but can impose significant costs on the loser of the conflict (Sell et al., 2012). The consequences of conflict would have placed great pressure on the male brain to develop ways of interpreting the chances of success, in order to determine when to avoid conflict or engage in aggressive and violent actions (Sell and al., 2012). The authors describe evolved mechanisms of aggression and their effects on the decisions of modern humans. At the heart of the article's premise are the characteristics of the male physique that seem suited to aggression. There are many gender differences that suggest the importance of violence and aggression in shaping the male body (Sell et al. 2012). The authors pointed to these sex differences as evidence of evolved weaponry and defenses. Two of the main mechanisms discussed in the article are upper body strength, which is closely related to fighting ability. (...