There are 6500 genes that are expressed differently between males and females.
Why are there males and females? Why are there two sexes instead of three, or twelve, or one?
What’s ironic, though, is that the females are attracted to a pheromone produced by these loser males. If the pheromone is applied to a winner male, he will instantly become a loser–meaning he will be chased by males and females alike, only the females won’t want to pummel him.