Male And Female Flies Joke

 A woman walked into the kitchen to find her husband stalking around with a fly swatter. 

"What are you doing?" she asked. 

"Hunting flies", her husband responded. 

"Oh. Killing any?" she asked. 

"Yep, 3 males, 2 females," he replied. 

Intrigued, she asked. "How can you tell?" 

"Three were on a beer can, two were on the phone," he said.