From the brains behind brains on, this is the moment of um.

Answering those questions that make you go.

Um,hmm. Mm-hmm. Mm-hmm.

Mm-hmm. Mm-hmm comes to you from 8 p.m. studios, I'm lefty. The butt cheek.

I'm proud to be the left butt cheek of a sassy pug named Theodore.

You know, I think I'm one of the most underappreciated parts of a dog's body.

As a butt cheek, I help with practically everything, chasing

balls, getting on and off the couch, even decorating the yard with fresh turds. But I'm getting off track.

Just that week, my owner took Theodore the Pug on a dreadful walk at the park.

As his left butt cheek, I have to help him power his bug body up one of the steepest hills I've ever seen.

And don't even get me started on this right, butt cheek.

What a slacker! Anyway, when we finally got to the top, I was so excited to see the view. But suddenly, everything went dark, and all I could feel was grass.

Theodore the sassy bug sat down.

Apparently I have to do all the work to get us to the view

and I'm also the resting cushion when we arrive.

In fact, my human friend Hannah was just asking about this.

Why don't dogs and cats have butt cheeks?

I would say, first of all, that especially when I look at at dogs I kind of think they do have butt cheeks.

I'm Alexandra Corrowitz. I study dog behavior and cognition at Barnard College in New York City.

So I mean they definitely have butts or what I like to call rumps, you know, because I'm a scientist.

I use a fancy word.

And sometimes you can see their rumps better when they don't have a tail.

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