Origins of Gender Differences During disagreements, men tend to experience greater physiological arousal than women, which comes in the form of increased heart rate and blood pressure. This may be why boys exhibit more aggressive behaviors than girls do, even when they are very young. Evolution may play role as well. Because women are able to bear only a limited number of children, procreation has favored men who can successfully compete for their attention and demonstrate their superiority to other males. Moreover, in their traditional role as hunters and providers, men were challenged to be bold, physical risk takers. By contrast, women have traditionally nurtured children. In that role, there is a advantage to creating safe environments, working cooperatively with others, and understanding the nuances of nonverbal communication. This may explain why women are often more sensitive to subtle cues and are more aligned to harmony and cooperation than competition