I think there's a country song that speaks to this particular phenomena.

Something about why guys show off, 'cause the chicks dig it... It's been awhile since I tuned into country.

From an anthropological point of view, there's probably something to do with demonstrating ones prowess to the other gender. The unsuccessful demonstration often results in the 'boys are dumb' mantra that we hear from so many of the ladies over time.

But then again, my sociology professor maintained that instinct had been bred out of the human animal thousands of years ago.

Or were we just talking about boy cats?