This episode is a real stinker, but it had to happen. We go behind the scenes on what makes butts and poop so funny. Why does the mere mention of them make us laugh?

We all have butts and we all poop. Those are the facts. But human butts are different than almost any other animal. We look into the evolution of butts, and find out how our senses of humor develop when we're kids. And we hear from comic Tim Platt on why he thinks butts and poop will always be funny. Plus, we’ll check in with Channel 2’s Bowel Action News team for some fast feces facts. Don’t forget to tune up your ears with the Mystery Sound.

One more thing… who farted?