Determining The Sex


I stopped at a friend's shop the other day and found him stalking
around with a fly swatter.

When I asked if he was gettin' any flies, he answered, "Yeah, 3 
males and 2 females".

Curious, I inquired as to how he could tell the difference.

He answered, "3 were on a beer can, and 2 were on the phone."


[Thanks to Les Pourciau]