The second theory is similar and is known as "evolutionary neuroandrogenic (ENA) theory of male aggression".   Testosterone and other androgens have evolved to masculinize a brain in order to be competitive even to the point of risking harm to the person and others. By doing so, individuals with masculinized brains as a result of pre-natal and adult life testosterone and androgens enhance their resource acquiring abilities in order to survive, attract and copulate with mates as much as possible.  The masculinization of the brain is not just mediated by testosterone levels at the adult stage, but also testosterone exposure in the womb as a fetus. Higher pre-natal testosterone indicated by a low digit ratio as well as adult testosterone levels increased risk of fouls or aggression among male players in a soccer game.  Studies have also found higher pre-natal testosterone or lower digit ratio to be correlated with higher aggression in males.     
Last but not least, cocoa nibs are the secret weapon that make these macho rice cakes so good for your testosterone levels. Think of these little morsels as chocolate chips that come from the earth. They may not be as sweet as actual chocolate chips, but they are a hell of a lot more beneficial. Raw cocoa nibs are jam-packed with minerals and antioxidants that help you keep a healthy gut and immune system. They also have an amazing ratio of fatty acids, which can assist testosterone production in active men.