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

Um, um, um, um, um, um, um, moment of um comes to you from APM Studios. I'm Anna Weigel.

Um.

Hey Anna.

Hey Anna.

Have you picked out your Halloween costume yet?

You know, I really appreciate that you're thinking about this in the

middle of June. Thanks. Because so am I. Yes, what are we thinking? I definitely know I want to go as some

kind of ferocious beast. Me too. I always say the more teeth your costume has, the more fun you're

going to have. I was thinking of going as a dinosaur.

I was thinking of going as a shark. So in another life, our ferocious beasts would have hung out together.

Well, maybe not together. But neighbors, sure. You know, why did your species survive and mine didn't,

if they were both around at the same time? Actually, funny you should ask, Jeffrey had a question about this.

Hi, my name is Jeffrey.

I live in Birmingham, Alabama.

And my question is, if sharks were older than dinosaurs, why didn't they die out with water dinosaurs?

My name is Karen Chin, and I am a professor of geological sciences at the University of

Colorado, and I'm also a curator of paleontology at the University of Colorado Museum of Natural

History. Paleontology is the study of ancient organisms other than humans. We study fungi, dinosaurs, mollusks, anything that's not human but is ancient.

I first want to clarify that there were really no water dinosaurs.

When people think of what we can call water dinosaurs, we're usually thinking of large marine reptiles,

like ichthyosaurs, pleasaurus, and mosasaurus. So I'm going to talk about, I'm going to

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