So now we know that Torosaurus is actually a grownup Triceratops.

There's a Triceratops in every museum in the world, but no one had ever collected a juvenile.

They thought Torosaurus should be kept and Triceratops thrown out, but that's not going to happen.

But there's another dinosaur that is found in this formation that looks like a Triceratops, except it's bigger, and it's called Torosaurus.

And everybody says, A Triceratops and a Torosaurus can't possibly be the same animal because one of them's bigger than the other one.

So Torosaurus is extinct.

As the juveniles are growing up, their horns actually curve backwards.

And I said, Well do we have any juvenile Torosauruses?

So one of my graduate students, John Scannella, looked through our whole collection and he actually discovered that the hole starting to form in Triceratops and, of course it's open, in Torosaurus so he found the transitional ones between Triceratops and Torosaurus, which was pretty cool.

And before the year 2000 now remember, Triceratops was first found in the 1800s before 2000, no one had ever seen a juvenile Triceratops.

But it's got these big holes in its shield.

So a colleague of mine at Berkley, he and I were looking at Triceratops.

And the little one is really spongy.

So we have a whole bunch of them at our museum.

I'll work till 6, then have dinner at the saloon...

If you look at the Triceratops, you can see it's changing, it's shape shifting.

So we went out and collected a whole bunch of stuff and we found a whole bunch of little ones.

But what was interesting was the adult Triceratops was also spongy.

And Torosaurus, when we cut into it, has mature bone.

And then, because the juveniles are in my collection, I cut them open and look inside.

Triceratops, if you've heard the news, a lot of the newscasters got it all wrong.

Dracorex is the littlest one, Stygimoloch is the middle size one, Pachycephalosaurus is the largest one.

So there's these two dinosaurs, T. Rex and Nanotyrannus.

Which of course means that Stygimoloch and Dracorex are extinct.

Hey, hey, Lonesome. Lonesome boy. Hey.

Lonesome, nothing...

We now call them non avian dinosaurs and avian dinosaurs.

The bone histology tells us that Edmontosaurus is a juvenile, or at least a sub adult, and the other one is an adult and we have an ontogeny.

We're not going to be able to make a dinosaur based on a dinosaur.

I mean, here's Edmontosaurus and Anatotitan.

It's a giant duck bill dinosaur.

You'd have a big dinosaur and a littler dinosaur.

Although the king of them all, Tyrannosaurus rex, lived millions of years after Borealopelta, the armoured dinosaur may have been hunted by some of its formidable ancestors.

And then there's this thing called Dracorex, Hogwart's Eye.

Dragon

Nylon?

You can call it a dinosaur, but look at the velociraptor the velociraptor is cool.

And sure enough, Nanotyrannus has juvenile bone and the bigger one has more mature bone.

So if we cut open Dracorex I cut open our Dracorex and look, it was spongy inside, really spongy inside.

Now if you want dinosaur DNA, I say go to the dinosaur.

So I picked a Camarasaurus, because the Camarasaurus was the most abundant of the sauropods in North America.

Here's the animal that was causing it trouble.

And the last one is T. Rex.

Peg Solitaire

Peg Solitaire