. In evolutionary terms success is measured by the production of offspring that survive to reproductive maturity. In the EEA, successful males were physically trigger and stronger and so would be those most capable of providing food and protecting their mates and offspring.
. Psychologically, males who were naturally more aggressive when their recourses were threatened pr when out hunting, would also have had an adaptive advantage. Such men might also have been prepared to attack other humans and take their resources in order to provide for their families.
. This gave males an advantage in terms of mate choice. Successful females chose mates who provide good genes, so big, strong men were favoured. Such men were also more likely to provide better resources in terms of food and protection, suggesting that those who displayed aggressive traits would be more successful than those who did not. Thus, competition for males has driven masculine aggression.