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

Um, um, um, um, um, um, um, um, moment of om comes to you from APM studios.

I'm fiddle, and I'm a dog.

Um, um.

Um. Um Hey, hi, hello there.

So nice to see you. You smell interesting.

Hey, do you want to go to the dog park?

I went to the dog park today, and there was a dog, and he was digging.

Yeah, dig, dig, dig, and he had his whole face in the mud.

There's so much cool stuff buried underground, rocks, tulip bulbs, sticks, poop from that big

scary neighbor cat, a toy that somebody else buried. Or maybe something called a fossil. My human, Anna,

says a fossil is like a bone, but it's not a bone. It's a thing that was a bone,

and then turn slowly into a rock. I like bones. Maybe I should dig. Will I find a fossil?

What happens if I do? Robert had the same question.

What do experts do when they find a fossil?

Let's talk to a human who knows the answer.

So if you see a fossil on the ground, what first thing you need to do is figure out where that fossil's coming from.

My name is Jamil Connor, and I am the associate curator of fossil reptiles at the Field Museum in Chicago.

I am a dinosaur paleobiologist. Most fossils come from

deserts, and the reason for this is because fossils can only form in sedimentary rocks. So these are

rocks that are created by tiny little bits of existing rocks. So for example, lots of accumulated sand, forming sandstone, or mud forming mudstone.

So as these layers of sedimentary rocks are forming, if an animal dies and falls into that

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