Game theory predicts that when two contestants are equally matched, the winner will be the one that values the prize most.Females, with their elevated reproductive costs, have higher nutritional demands than males and are more at risk from going hungry. Undernourished females are unlikely to produce quality eggs or support pregnancy and lactation, but a skinny male can still shoot viable sperm and fire his genes into the next generation. So, females have more to lose in the reproductive fitness stakes and will therefore be expected to fight harder for resources.
