[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:00.00,0:00:03.00,Default,,0000,0000,0000,,Shall I ask for a show of hands
Dialogue: 0,0:00:03.00,0:00:05.00,Default,,0000,0000,0000,,or a clapping
Dialogue: 0,0:00:05.00,0:00:08.00,Default,,0000,0000,0000,,of people in different generations?
Dialogue: 0,0:00:08.00,0:00:10.00,Default,,0000,0000,0000,,I'm interested in how many
Dialogue: 0,0:00:10.00,0:00:12.00,Default,,0000,0000,0000,,are three to 12 years old.
Dialogue: 0,0:00:12.00,0:00:16.00,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:00:16.00,0:00:19.00,Default,,0000,0000,0000,,None, huh?
Dialogue: 0,0:00:19.00,0:00:21.00,Default,,0000,0000,0000,,All right.
Dialogue: 0,0:00:21.00,0:00:23.00,Default,,0000,0000,0000,,I'm going to talk about dinosaurs.
Dialogue: 0,0:00:23.00,0:00:26.00,Default,,0000,0000,0000,,Do you remember dinosaurs when you were that age?
Dialogue: 0,0:00:26.00,0:00:31.00,Default,,0000,0000,0000,,(Applause)
Dialogue: 0,0:00:33.00,0:00:36.00,Default,,0000,0000,0000,,Dinosaurs are kind of funny, you know.
Dialogue: 0,0:00:36.00,0:00:38.00,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:00:38.00,0:00:40.00,Default,,0000,0000,0000,,We're going to kind of go in a different direction right now.
Dialogue: 0,0:00:40.00,0:00:43.00,Default,,0000,0000,0000,,I hope you all realize that.
Dialogue: 0,0:00:43.00,0:00:45.00,Default,,0000,0000,0000,,So I'll just give you my message up front:
Dialogue: 0,0:00:45.00,0:00:47.00,Default,,0000,0000,0000,,Try not to go extinct.
Dialogue: 0,0:00:47.00,0:00:49.00,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:00:49.00,0:00:51.00,Default,,0000,0000,0000,,That's it.
Dialogue: 0,0:00:51.00,0:00:55.00,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:00:55.00,0:00:57.00,Default,,0000,0000,0000,,People ask me a lot --
Dialogue: 0,0:00:57.00,0:01:00.00,Default,,0000,0000,0000,,in fact, one of the most asked questions I get
Dialogue: 0,0:01:00.00,0:01:04.00,Default,,0000,0000,0000,,is, why do children like dinosaurs so much?
Dialogue: 0,0:01:04.00,0:01:06.00,Default,,0000,0000,0000,,What's the fascination?
Dialogue: 0,0:01:06.00,0:01:09.00,Default,,0000,0000,0000,,And I usually just say,
Dialogue: 0,0:01:09.00,0:01:11.00,Default,,0000,0000,0000,,"Well dinosaurs were big,
Dialogue: 0,0:01:11.00,0:01:14.00,Default,,0000,0000,0000,,different and gone."
Dialogue: 0,0:01:14.00,0:01:16.00,Default,,0000,0000,0000,,They're all gone.
Dialogue: 0,0:01:16.00,0:01:18.00,Default,,0000,0000,0000,,Well that's not true,
Dialogue: 0,0:01:18.00,0:01:20.00,Default,,0000,0000,0000,,but we'll get to the goose in a minute.
Dialogue: 0,0:01:20.00,0:01:23.00,Default,,0000,0000,0000,,So that's sort of the theme:
Dialogue: 0,0:01:23.00,0:01:27.00,Default,,0000,0000,0000,,big, different and gone.
Dialogue: 0,0:01:27.00,0:01:29.00,Default,,0000,0000,0000,,The title of my talk:
Dialogue: 0,0:01:29.00,0:01:31.00,Default,,0000,0000,0000,,Shape-shifting Dinosaurs:
Dialogue: 0,0:01:31.00,0:01:33.00,Default,,0000,0000,0000,,The Cause of a Premature Extinction.
Dialogue: 0,0:01:33.00,0:01:36.00,Default,,0000,0000,0000,,Now I assume that we remember dinosaurs.
Dialogue: 0,0:01:36.00,0:01:39.00,Default,,0000,0000,0000,,And there's lots of different shapes.
Dialogue: 0,0:01:39.00,0:01:42.00,Default,,0000,0000,0000,,Lots of different kinds.
Dialogue: 0,0:01:42.00,0:01:44.00,Default,,0000,0000,0000,,A long time ago,
Dialogue: 0,0:01:44.00,0:01:46.00,Default,,0000,0000,0000,,back in the early 1900s,
Dialogue: 0,0:01:46.00,0:01:49.00,Default,,0000,0000,0000,,museums were out looking for dinosaurs.
Dialogue: 0,0:01:49.00,0:01:52.00,Default,,0000,0000,0000,,They went out and gathered them up.
Dialogue: 0,0:01:52.00,0:01:54.00,Default,,0000,0000,0000,,And this is an interesting story.
Dialogue: 0,0:01:54.00,0:01:57.00,Default,,0000,0000,0000,,Every museum wanted a little bigger or better one
Dialogue: 0,0:01:57.00,0:01:59.00,Default,,0000,0000,0000,,than anybody else had.
Dialogue: 0,0:01:59.00,0:02:02.00,Default,,0000,0000,0000,,So if the museum in Toronto went out
Dialogue: 0,0:02:02.00,0:02:05.00,Default,,0000,0000,0000,,and collected a Tyrannosaur, a big one,
Dialogue: 0,0:02:05.00,0:02:08.00,Default,,0000,0000,0000,,then the museum in Ottawa wanted a bigger one
Dialogue: 0,0:02:08.00,0:02:10.00,Default,,0000,0000,0000,,and a better one.
Dialogue: 0,0:02:10.00,0:02:12.00,Default,,0000,0000,0000,,And that happened for all museums.
Dialogue: 0,0:02:12.00,0:02:14.00,Default,,0000,0000,0000,,So everyone was out looking
Dialogue: 0,0:02:14.00,0:02:17.00,Default,,0000,0000,0000,,for all these bigger and better dinosaurs.
Dialogue: 0,0:02:17.00,0:02:21.00,Default,,0000,0000,0000,,And this was in the early 1900s.
Dialogue: 0,0:02:21.00,0:02:24.00,Default,,0000,0000,0000,,By about 1970,
Dialogue: 0,0:02:24.00,0:02:26.00,Default,,0000,0000,0000,,some scientists were sitting around
Dialogue: 0,0:02:26.00,0:02:29.00,Default,,0000,0000,0000,,and they thought, "What in the world?
Dialogue: 0,0:02:29.00,0:02:31.00,Default,,0000,0000,0000,,Look at these dinosaurs.
Dialogue: 0,0:02:31.00,0:02:33.00,Default,,0000,0000,0000,,They're all big.
Dialogue: 0,0:02:33.00,0:02:36.00,Default,,0000,0000,0000,,Where are all the little ones?"
Dialogue: 0,0:02:38.00,0:02:40.00,Default,,0000,0000,0000,,And they thought about it
Dialogue: 0,0:02:40.00,0:02:42.00,Default,,0000,0000,0000,,and they even wrote papers about it:
Dialogue: 0,0:02:42.00,0:02:44.00,Default,,0000,0000,0000,,"Where are the little dinosaurs?"
Dialogue: 0,0:02:44.00,0:02:49.00,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:02:52.00,0:02:56.00,Default,,0000,0000,0000,,Well, go to a museum, you'll see,
Dialogue: 0,0:02:56.00,0:02:59.00,Default,,0000,0000,0000,,see how many baby dinosaurs there are.
Dialogue: 0,0:02:59.00,0:03:02.00,Default,,0000,0000,0000,,People assumed -- and this was actually a problem --
Dialogue: 0,0:03:02.00,0:03:04.00,Default,,0000,0000,0000,,people assumed
Dialogue: 0,0:03:04.00,0:03:06.00,Default,,0000,0000,0000,,that if they had little dinosaurs,
Dialogue: 0,0:03:06.00,0:03:08.00,Default,,0000,0000,0000,,if they had juvenile dinosaurs,
Dialogue: 0,0:03:08.00,0:03:10.00,Default,,0000,0000,0000,,they'd be easy to identify.
Dialogue: 0,0:03:10.00,0:03:12.00,Default,,0000,0000,0000,,You'd have a big dinosaur
Dialogue: 0,0:03:12.00,0:03:15.00,Default,,0000,0000,0000,,and a littler dinosaur.
Dialogue: 0,0:03:15.00,0:03:18.00,Default,,0000,0000,0000,,But all they had were big dinosaurs.
Dialogue: 0,0:03:18.00,0:03:21.00,Default,,0000,0000,0000,,And it comes down to a couple of things.
Dialogue: 0,0:03:21.00,0:03:25.00,Default,,0000,0000,0000,,First off, scientists have egos,
Dialogue: 0,0:03:25.00,0:03:29.00,Default,,0000,0000,0000,,and scientists like to name dinosaurs.
Dialogue: 0,0:03:29.00,0:03:31.00,Default,,0000,0000,0000,,They like to name anything.
Dialogue: 0,0:03:31.00,0:03:34.00,Default,,0000,0000,0000,,Everybody likes to have their own animal that they named.
Dialogue: 0,0:03:34.00,0:03:37.00,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:03:37.00,0:03:40.00,Default,,0000,0000,0000,,And so every time they found something that looked a little different,
Dialogue: 0,0:03:40.00,0:03:43.00,Default,,0000,0000,0000,,they named it something different.
Dialogue: 0,0:03:43.00,0:03:45.00,Default,,0000,0000,0000,,And what happened, of course,
Dialogue: 0,0:03:45.00,0:03:48.00,Default,,0000,0000,0000,,is we ended up with a whole bunch of different dinosaurs.
Dialogue: 0,0:03:50.00,0:03:53.00,Default,,0000,0000,0000,,In 1975,
Dialogue: 0,0:03:53.00,0:03:56.00,Default,,0000,0000,0000,,a light went on in somebody's head.
Dialogue: 0,0:03:56.00,0:03:58.00,Default,,0000,0000,0000,,Dr. Peter Dodson
Dialogue: 0,0:03:58.00,0:04:00.00,Default,,0000,0000,0000,,at the University of Pennsylvania
Dialogue: 0,0:04:00.00,0:04:03.00,Default,,0000,0000,0000,,actually realized
Dialogue: 0,0:04:03.00,0:04:06.00,Default,,0000,0000,0000,,that dinosaurs grew
Dialogue: 0,0:04:06.00,0:04:08.00,Default,,0000,0000,0000,,kind of like birds do,
Dialogue: 0,0:04:08.00,0:04:10.00,Default,,0000,0000,0000,,which is different
Dialogue: 0,0:04:10.00,0:04:12.00,Default,,0000,0000,0000,,than the way reptiles grow.
Dialogue: 0,0:04:12.00,0:04:14.00,Default,,0000,0000,0000,,And in fact,
Dialogue: 0,0:04:14.00,0:04:17.00,Default,,0000,0000,0000,,he used the cassowary as an example.
Dialogue: 0,0:04:17.00,0:04:20.00,Default,,0000,0000,0000,,And it's kind of cool -- if you look at the cassowary,
Dialogue: 0,0:04:20.00,0:04:23.00,Default,,0000,0000,0000,,or any of the birds that have crests on their heads,
Dialogue: 0,0:04:23.00,0:04:25.00,Default,,0000,0000,0000,,they actually grow
Dialogue: 0,0:04:25.00,0:04:27.00,Default,,0000,0000,0000,,to about 80 percent adult size
Dialogue: 0,0:04:27.00,0:04:30.00,Default,,0000,0000,0000,,before the crest starts to grow.
Dialogue: 0,0:04:30.00,0:04:33.00,Default,,0000,0000,0000,,Now think about that.
Dialogue: 0,0:04:33.00,0:04:36.00,Default,,0000,0000,0000,,They're basically retaining their juvenile characteristics
Dialogue: 0,0:04:36.00,0:04:39.00,Default,,0000,0000,0000,,very late in what we call ontogeny.
Dialogue: 0,0:04:39.00,0:04:43.00,Default,,0000,0000,0000,,So allometric cranial ontogeny
Dialogue: 0,0:04:43.00,0:04:46.00,Default,,0000,0000,0000,,is relative skull growth.
Dialogue: 0,0:04:46.00,0:04:48.00,Default,,0000,0000,0000,,So you can see
Dialogue: 0,0:04:48.00,0:04:50.00,Default,,0000,0000,0000,,that if you actually found one
Dialogue: 0,0:04:50.00,0:04:53.00,Default,,0000,0000,0000,,that was 80 percent grown
Dialogue: 0,0:04:53.00,0:04:56.00,Default,,0000,0000,0000,,and you didn't know that it was going to grow up to a cassowary,
Dialogue: 0,0:04:56.00,0:04:59.00,Default,,0000,0000,0000,,you would think they were two different animals.
Dialogue: 0,0:05:00.00,0:05:03.00,Default,,0000,0000,0000,,So this was a problem,
Dialogue: 0,0:05:03.00,0:05:06.00,Default,,0000,0000,0000,,and Peter Dodson pointed this out
Dialogue: 0,0:05:06.00,0:05:08.00,Default,,0000,0000,0000,,using some duck-billed dinosaurs
Dialogue: 0,0:05:08.00,0:05:10.00,Default,,0000,0000,0000,,then called Hypacrosaurus.
Dialogue: 0,0:05:10.00,0:05:12.00,Default,,0000,0000,0000,,And he showed
Dialogue: 0,0:05:12.00,0:05:15.00,Default,,0000,0000,0000,,that if you were to take a baby and an adult
Dialogue: 0,0:05:15.00,0:05:18.00,Default,,0000,0000,0000,,and make an average of what it should look like,
Dialogue: 0,0:05:18.00,0:05:21.00,Default,,0000,0000,0000,,if it grew in sort of a linear fashion,
Dialogue: 0,0:05:21.00,0:05:23.00,Default,,0000,0000,0000,,it would have a crest
Dialogue: 0,0:05:23.00,0:05:26.00,Default,,0000,0000,0000,,about half the size of the adult.
Dialogue: 0,0:05:26.00,0:05:28.00,Default,,0000,0000,0000,,But the actual sub-adult
Dialogue: 0,0:05:28.00,0:05:30.00,Default,,0000,0000,0000,,at 65 percent
Dialogue: 0,0:05:30.00,0:05:32.00,Default,,0000,0000,0000,,had no crest at all.
Dialogue: 0,0:05:32.00,0:05:34.00,Default,,0000,0000,0000,,So this was interesting.
Dialogue: 0,0:05:34.00,0:05:37.00,Default,,0000,0000,0000,,So this is where
Dialogue: 0,0:05:37.00,0:05:40.00,Default,,0000,0000,0000,,people went astray again.
Dialogue: 0,0:05:40.00,0:05:42.00,Default,,0000,0000,0000,,I mean, if they'd have just taken that,
Dialogue: 0,0:05:42.00,0:05:45.00,Default,,0000,0000,0000,,taken Peter Dodson's work, and gone on with that,
Dialogue: 0,0:05:45.00,0:05:47.00,Default,,0000,0000,0000,,then we would have a lot less dinosaurs
Dialogue: 0,0:05:47.00,0:05:49.00,Default,,0000,0000,0000,,than we have.
Dialogue: 0,0:05:49.00,0:05:51.00,Default,,0000,0000,0000,,But scientists have egos;
Dialogue: 0,0:05:51.00,0:05:54.00,Default,,0000,0000,0000,,they like to name things.
Dialogue: 0,0:05:54.00,0:05:57.00,Default,,0000,0000,0000,,And so they went on naming dinosaurs
Dialogue: 0,0:05:57.00,0:06:00.00,Default,,0000,0000,0000,,because they were different.
Dialogue: 0,0:06:00.00,0:06:02.00,Default,,0000,0000,0000,,Now we have a way of actually testing
Dialogue: 0,0:06:02.00,0:06:05.00,Default,,0000,0000,0000,,to see whether a dinosaur, or any animal,
Dialogue: 0,0:06:05.00,0:06:08.00,Default,,0000,0000,0000,,is a young one or an older one.
Dialogue: 0,0:06:08.00,0:06:11.00,Default,,0000,0000,0000,,And that's by actually cutting into their bones.
Dialogue: 0,0:06:11.00,0:06:15.00,Default,,0000,0000,0000,,But cutting into the bones of a dinosaur
Dialogue: 0,0:06:15.00,0:06:18.00,Default,,0000,0000,0000,,is hard to do, as you can imagine,
Dialogue: 0,0:06:18.00,0:06:21.00,Default,,0000,0000,0000,,because in museums
Dialogue: 0,0:06:21.00,0:06:25.00,Default,,0000,0000,0000,,bones are precious.
Dialogue: 0,0:06:25.00,0:06:28.00,Default,,0000,0000,0000,,You go into a museum and they take really good care of them.
Dialogue: 0,0:06:28.00,0:06:31.00,Default,,0000,0000,0000,,They put them in foam, little containers.
Dialogue: 0,0:06:31.00,0:06:34.00,Default,,0000,0000,0000,,They're very well taken care of.
Dialogue: 0,0:06:35.00,0:06:37.00,Default,,0000,0000,0000,,They don't like it if you come in
Dialogue: 0,0:06:37.00,0:06:39.00,Default,,0000,0000,0000,,and want to saw them open and look inside.
Dialogue: 0,0:06:39.00,0:06:41.00,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:06:41.00,0:06:44.00,Default,,0000,0000,0000,,So they don't normally let you do that.
Dialogue: 0,0:06:44.00,0:06:47.00,Default,,0000,0000,0000,,But I have a museum
Dialogue: 0,0:06:47.00,0:06:49.00,Default,,0000,0000,0000,,and I collect dinosaurs
Dialogue: 0,0:06:49.00,0:06:51.00,Default,,0000,0000,0000,,and I can saw mine open.
Dialogue: 0,0:06:51.00,0:06:53.00,Default,,0000,0000,0000,,So that's what I do.
Dialogue: 0,0:06:53.00,0:06:58.00,Default,,0000,0000,0000,,(Applause)
Dialogue: 0,0:06:58.00,0:07:03.00,Default,,0000,0000,0000,,So if you cut open a little dinosaur,
Dialogue: 0,0:07:03.00,0:07:05.00,Default,,0000,0000,0000,,it's very spongy inside like A.
Dialogue: 0,0:07:05.00,0:07:07.00,Default,,0000,0000,0000,,And if you cut into an older dinosaur,
Dialogue: 0,0:07:07.00,0:07:09.00,Default,,0000,0000,0000,,it's very massive.
Dialogue: 0,0:07:09.00,0:07:11.00,Default,,0000,0000,0000,,You can tell it's mature bone.
Dialogue: 0,0:07:11.00,0:07:14.00,Default,,0000,0000,0000,,So it's real easy to tell them apart.
Dialogue: 0,0:07:14.00,0:07:16.00,Default,,0000,0000,0000,,So what I want to do
Dialogue: 0,0:07:16.00,0:07:18.00,Default,,0000,0000,0000,,is show you these.
Dialogue: 0,0:07:18.00,0:07:22.00,Default,,0000,0000,0000,,In North America in the Northern Plains of the United States
Dialogue: 0,0:07:22.00,0:07:26.00,Default,,0000,0000,0000,,and the Southern Plains of Alberta and Saskatchewan,
Dialogue: 0,0:07:26.00,0:07:29.00,Default,,0000,0000,0000,,there's this unit of rock called the Hell Creek Formation
Dialogue: 0,0:07:29.00,0:07:32.00,Default,,0000,0000,0000,,that produces the last dinosaurs that lived on Earth.
Dialogue: 0,0:07:32.00,0:07:34.00,Default,,0000,0000,0000,,And there are 12 of them
Dialogue: 0,0:07:34.00,0:07:36.00,Default,,0000,0000,0000,,that everyone recognizes --
Dialogue: 0,0:07:36.00,0:07:38.00,Default,,0000,0000,0000,,I mean the 12 primary dinosaurs
Dialogue: 0,0:07:38.00,0:07:40.00,Default,,0000,0000,0000,,that went extinct.
Dialogue: 0,0:07:40.00,0:07:43.00,Default,,0000,0000,0000,,And so we will evaluate them.
Dialogue: 0,0:07:43.00,0:07:45.00,Default,,0000,0000,0000,,And that's sort of what I've been doing.
Dialogue: 0,0:07:45.00,0:07:48.00,Default,,0000,0000,0000,,So my students, my staff,
Dialogue: 0,0:07:48.00,0:07:51.00,Default,,0000,0000,0000,,we've been cutting them open.
Dialogue: 0,0:07:51.00,0:07:53.00,Default,,0000,0000,0000,,Now as you can imagine,
Dialogue: 0,0:07:53.00,0:07:55.00,Default,,0000,0000,0000,,cutting open a leg bone is one thing,
Dialogue: 0,0:07:55.00,0:07:58.00,Default,,0000,0000,0000,,but when you go to a museum
Dialogue: 0,0:07:58.00,0:08:00.00,Default,,0000,0000,0000,,and say, "You don't mind if I cut open
Dialogue: 0,0:08:00.00,0:08:03.00,Default,,0000,0000,0000,,your dinosaur's skull do you?"
Dialogue: 0,0:08:03.00,0:08:06.00,Default,,0000,0000,0000,,they say, "Go away."
Dialogue: 0,0:08:06.00,0:08:11.00,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:08:11.00,0:08:15.00,Default,,0000,0000,0000,,So here are 12 dinosaurs.
Dialogue: 0,0:08:15.00,0:08:18.00,Default,,0000,0000,0000,,And we want to look at these three first.
Dialogue: 0,0:08:18.00,0:08:21.00,Default,,0000,0000,0000,,So these are dinosaurs that are called Pachycephalosaurs.
Dialogue: 0,0:08:21.00,0:08:23.00,Default,,0000,0000,0000,,And everybody knows
Dialogue: 0,0:08:23.00,0:08:25.00,Default,,0000,0000,0000,,that these three animals are related.
Dialogue: 0,0:08:25.00,0:08:27.00,Default,,0000,0000,0000,,And the assumption is
Dialogue: 0,0:08:27.00,0:08:29.00,Default,,0000,0000,0000,,is that they're related
Dialogue: 0,0:08:29.00,0:08:32.00,Default,,0000,0000,0000,,like cousins or whatever.
Dialogue: 0,0:08:32.00,0:08:34.00,Default,,0000,0000,0000,,But no one ever considered
Dialogue: 0,0:08:34.00,0:08:37.00,Default,,0000,0000,0000,,that they might be more closely related.
Dialogue: 0,0:08:37.00,0:08:39.00,Default,,0000,0000,0000,,In other words,
Dialogue: 0,0:08:39.00,0:08:42.00,Default,,0000,0000,0000,,people looked at them and they saw the differences.
Dialogue: 0,0:08:42.00,0:08:44.00,Default,,0000,0000,0000,,And you all know
Dialogue: 0,0:08:44.00,0:08:46.00,Default,,0000,0000,0000,,that if you are going to determine
Dialogue: 0,0:08:46.00,0:08:48.00,Default,,0000,0000,0000,,whether you're related to your brother or your sister,
Dialogue: 0,0:08:48.00,0:08:52.00,Default,,0000,0000,0000,,you can't do it by looking at differences.
Dialogue: 0,0:08:52.00,0:08:54.00,Default,,0000,0000,0000,,You can only determine relatedness
Dialogue: 0,0:08:54.00,0:08:56.00,Default,,0000,0000,0000,,by looking for similarities.
Dialogue: 0,0:08:56.00,0:08:58.00,Default,,0000,0000,0000,,So people were looking at these
Dialogue: 0,0:08:58.00,0:09:00.00,Default,,0000,0000,0000,,and they were talking about how different they are.
Dialogue: 0,0:09:00.00,0:09:03.00,Default,,0000,0000,0000,,Pachycephalosaurus has a big, thick dome on its head,
Dialogue: 0,0:09:03.00,0:09:06.00,Default,,0000,0000,0000,,and it's got some little bumps on the back of its head,
Dialogue: 0,0:09:06.00,0:09:10.00,Default,,0000,0000,0000,,and it's got a bunch of gnarly things on the end of its nose.
Dialogue: 0,0:09:10.00,0:09:12.00,Default,,0000,0000,0000,,And then Stygimoloch, another dinosaur
Dialogue: 0,0:09:12.00,0:09:16.00,Default,,0000,0000,0000,,from the same age, lived at the same time,
Dialogue: 0,0:09:16.00,0:09:18.00,Default,,0000,0000,0000,,has spikes sticking out the back of its head.
Dialogue: 0,0:09:18.00,0:09:20.00,Default,,0000,0000,0000,,It's got a little, tiny dome,
Dialogue: 0,0:09:20.00,0:09:24.00,Default,,0000,0000,0000,,and it's got a bunch of gnarly stuff on its nose.
Dialogue: 0,0:09:24.00,0:09:26.00,Default,,0000,0000,0000,,And then there's this thing called Dracorex,
Dialogue: 0,0:09:26.00,0:09:28.00,Default,,0000,0000,0000,,Hogwart's Eye.
Dialogue: 0,0:09:28.00,0:09:31.00,Default,,0000,0000,0000,,Guess where that came from? Dragon.
Dialogue: 0,0:09:31.00,0:09:33.00,Default,,0000,0000,0000,,So here's a dinosaur
Dialogue: 0,0:09:33.00,0:09:36.00,Default,,0000,0000,0000,,that has spikes sticking out of its head, no dome
Dialogue: 0,0:09:36.00,0:09:39.00,Default,,0000,0000,0000,,and gnarly stuff on its nose.
Dialogue: 0,0:09:39.00,0:09:42.00,Default,,0000,0000,0000,,Nobody noticed the gnarly stuff sort of looked alike.
Dialogue: 0,0:09:42.00,0:09:44.00,Default,,0000,0000,0000,,But they did look at these three
Dialogue: 0,0:09:44.00,0:09:46.00,Default,,0000,0000,0000,,and they said, "These are three different dinosaurs,
Dialogue: 0,0:09:46.00,0:09:49.00,Default,,0000,0000,0000,,and Dracorex is probably the most primitive of them.
Dialogue: 0,0:09:49.00,0:09:52.00,Default,,0000,0000,0000,,And the other one is more primitive than the other.
Dialogue: 0,0:09:52.00,0:09:55.00,Default,,0000,0000,0000,,It's unclear to me
Dialogue: 0,0:09:55.00,0:09:58.00,Default,,0000,0000,0000,,how they actually sorted these three of them out.
Dialogue: 0,0:09:58.00,0:10:00.00,Default,,0000,0000,0000,,But if you line them up,
Dialogue: 0,0:10:00.00,0:10:03.00,Default,,0000,0000,0000,,if you just take those three skulls and just line them up,
Dialogue: 0,0:10:03.00,0:10:05.00,Default,,0000,0000,0000,,they line up like this.
Dialogue: 0,0:10:05.00,0:10:07.00,Default,,0000,0000,0000,,Dracorex is the littlest one,
Dialogue: 0,0:10:07.00,0:10:09.00,Default,,0000,0000,0000,,Stygimoloch is the middle size one,
Dialogue: 0,0:10:09.00,0:10:12.00,Default,,0000,0000,0000,,Pachycephalosaurus is the largest one.
Dialogue: 0,0:10:12.00,0:10:14.00,Default,,0000,0000,0000,,And one would think,
Dialogue: 0,0:10:14.00,0:10:16.00,Default,,0000,0000,0000,,that should give me a clue.
Dialogue: 0,0:10:16.00,0:10:18.00,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:10:18.00,0:10:21.00,Default,,0000,0000,0000,,But it didn't give them a clue.
Dialogue: 0,0:10:21.00,0:10:24.00,Default,,0000,0000,0000,,Because, well we know why.
Dialogue: 0,0:10:24.00,0:10:27.00,Default,,0000,0000,0000,,Scientists like to name things.
Dialogue: 0,0:10:27.00,0:10:29.00,Default,,0000,0000,0000,,So if we cut open
Dialogue: 0,0:10:29.00,0:10:31.00,Default,,0000,0000,0000,,Dracorex --
Dialogue: 0,0:10:31.00,0:10:33.00,Default,,0000,0000,0000,,I cut open our Dracorex --
Dialogue: 0,0:10:33.00,0:10:35.00,Default,,0000,0000,0000,,and look, it was spongy inside,
Dialogue: 0,0:10:35.00,0:10:37.00,Default,,0000,0000,0000,,really spongy inside.
Dialogue: 0,0:10:37.00,0:10:39.00,Default,,0000,0000,0000,,I mean, it is a juvenile
Dialogue: 0,0:10:39.00,0:10:41.00,Default,,0000,0000,0000,,and it's growing really fast.
Dialogue: 0,0:10:41.00,0:10:43.00,Default,,0000,0000,0000,,So it is going to get bigger.
Dialogue: 0,0:10:43.00,0:10:45.00,Default,,0000,0000,0000,,If you cut open Stygimoloch,
Dialogue: 0,0:10:45.00,0:10:47.00,Default,,0000,0000,0000,,it is doing the same thing.
Dialogue: 0,0:10:47.00,0:10:49.00,Default,,0000,0000,0000,,The dome, that little dome,
Dialogue: 0,0:10:49.00,0:10:51.00,Default,,0000,0000,0000,,is growing really fast.
Dialogue: 0,0:10:51.00,0:10:53.00,Default,,0000,0000,0000,,It's inflating very fast.
Dialogue: 0,0:10:53.00,0:10:56.00,Default,,0000,0000,0000,,What's interesting is the spike on the back of the Dracorex
Dialogue: 0,0:10:56.00,0:10:58.00,Default,,0000,0000,0000,,was growing very fast as well.
Dialogue: 0,0:10:58.00,0:11:00.00,Default,,0000,0000,0000,,The spikes on the back of the Stygimoloch
Dialogue: 0,0:11:00.00,0:11:02.00,Default,,0000,0000,0000,,are actually resorbing,
Dialogue: 0,0:11:02.00,0:11:04.00,Default,,0000,0000,0000,,which means they're getting smaller
Dialogue: 0,0:11:04.00,0:11:06.00,Default,,0000,0000,0000,,as that dome is getting bigger.
Dialogue: 0,0:11:06.00,0:11:09.00,Default,,0000,0000,0000,,And if we look at Pachycephalosaurus,
Dialogue: 0,0:11:09.00,0:11:12.00,Default,,0000,0000,0000,,Pachycephalosaurus has a solid dome
Dialogue: 0,0:11:12.00,0:11:15.00,Default,,0000,0000,0000,,and its little bumps on the back of its head
Dialogue: 0,0:11:15.00,0:11:17.00,Default,,0000,0000,0000,,were also resorbing.
Dialogue: 0,0:11:17.00,0:11:19.00,Default,,0000,0000,0000,,So just with these three dinosaurs,
Dialogue: 0,0:11:19.00,0:11:21.00,Default,,0000,0000,0000,,you can easily -- as a scientist --
Dialogue: 0,0:11:21.00,0:11:23.00,Default,,0000,0000,0000,,we can easily hypothesize
Dialogue: 0,0:11:23.00,0:11:25.00,Default,,0000,0000,0000,,that it is just a growth series
Dialogue: 0,0:11:25.00,0:11:28.00,Default,,0000,0000,0000,,of the same animal.
Dialogue: 0,0:11:28.00,0:11:31.00,Default,,0000,0000,0000,,Which of course means
Dialogue: 0,0:11:31.00,0:11:35.00,Default,,0000,0000,0000,,that Stygimoloch and Dracorex
Dialogue: 0,0:11:35.00,0:11:37.00,Default,,0000,0000,0000,,are extinct.
Dialogue: 0,0:11:37.00,0:11:42.00,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:11:42.00,0:11:44.00,Default,,0000,0000,0000,,Okay.
Dialogue: 0,0:11:46.00,0:11:49.00,Default,,0000,0000,0000,,Which of course means
Dialogue: 0,0:11:49.00,0:11:53.00,Default,,0000,0000,0000,,we have 10 primary dinosaurs to deal with.
Dialogue: 0,0:11:53.00,0:11:55.00,Default,,0000,0000,0000,,So a colleague of mine at Berkley,
Dialogue: 0,0:11:55.00,0:11:58.00,Default,,0000,0000,0000,,he and I were looking at Triceratops.
Dialogue: 0,0:11:58.00,0:12:00.00,Default,,0000,0000,0000,,And before the year 2000 --
Dialogue: 0,0:12:00.00,0:12:02.00,Default,,0000,0000,0000,,now remember,
Dialogue: 0,0:12:02.00,0:12:04.00,Default,,0000,0000,0000,,Triceratops was first found in the 1800s --
Dialogue: 0,0:12:04.00,0:12:07.00,Default,,0000,0000,0000,,before 2000, no one had ever seen
Dialogue: 0,0:12:07.00,0:12:10.00,Default,,0000,0000,0000,,a juvenile Triceratops.
Dialogue: 0,0:12:10.00,0:12:13.00,Default,,0000,0000,0000,,There's a Triceratops in every museum in the world,
Dialogue: 0,0:12:13.00,0:12:17.00,Default,,0000,0000,0000,,but no one had ever collected a juvenile.
Dialogue: 0,0:12:17.00,0:12:19.00,Default,,0000,0000,0000,,And we know why, right?
Dialogue: 0,0:12:19.00,0:12:22.00,Default,,0000,0000,0000,,Because everybody wants to have a big one.
Dialogue: 0,0:12:22.00,0:12:24.00,Default,,0000,0000,0000,,So everyone had a big one.
Dialogue: 0,0:12:24.00,0:12:26.00,Default,,0000,0000,0000,,So we went out and collected a whole bunch of stuff
Dialogue: 0,0:12:26.00,0:12:28.00,Default,,0000,0000,0000,,and we found a whole bunch of little ones.
Dialogue: 0,0:12:28.00,0:12:32.00,Default,,0000,0000,0000,,They're everywhere. They're all over the place.
Dialogue: 0,0:12:32.00,0:12:34.00,Default,,0000,0000,0000,,So we have a whole bunch of them at our museum.
Dialogue: 0,0:12:34.00,0:12:39.00,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:12:39.00,0:12:41.00,Default,,0000,0000,0000,,And everybody says it's because I have a little museum.
Dialogue: 0,0:12:41.00,0:12:44.00,Default,,0000,0000,0000,,When you have a little museum, you have little dinosaurs.
Dialogue: 0,0:12:44.00,0:12:47.00,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:12:47.00,0:12:49.00,Default,,0000,0000,0000,,If you look at the Triceratops,
Dialogue: 0,0:12:49.00,0:12:51.00,Default,,0000,0000,0000,,you can see it's changing, it's shape-shifting.
Dialogue: 0,0:12:51.00,0:12:53.00,Default,,0000,0000,0000,,As the juveniles are growing up,
Dialogue: 0,0:12:53.00,0:12:55.00,Default,,0000,0000,0000,,their horns actually curve backwards.
Dialogue: 0,0:12:55.00,0:12:57.00,Default,,0000,0000,0000,,And then as they grow older,
Dialogue: 0,0:12:57.00,0:12:59.00,Default,,0000,0000,0000,,the horns grow forward.
Dialogue: 0,0:12:59.00,0:13:01.00,Default,,0000,0000,0000,,And that's pretty cool.
Dialogue: 0,0:13:01.00,0:13:03.00,Default,,0000,0000,0000,,If you look along the edge of the frill,
Dialogue: 0,0:13:03.00,0:13:06.00,Default,,0000,0000,0000,,they have these little triangular bones
Dialogue: 0,0:13:06.00,0:13:08.00,Default,,0000,0000,0000,,that actually grow big as triangles
Dialogue: 0,0:13:08.00,0:13:11.00,Default,,0000,0000,0000,,and then they flatten against the frill
Dialogue: 0,0:13:11.00,0:13:13.00,Default,,0000,0000,0000,,pretty much like the spikes do
Dialogue: 0,0:13:13.00,0:13:16.00,Default,,0000,0000,0000,,on the Pachycephalosaurs.
Dialogue: 0,0:13:16.00,0:13:20.00,Default,,0000,0000,0000,,And then, because the juveniles are in my collection,
Dialogue: 0,0:13:20.00,0:13:22.00,Default,,0000,0000,0000,,I cut them open
Dialogue: 0,0:13:22.00,0:13:24.00,Default,,0000,0000,0000,,and look inside.
Dialogue: 0,0:13:24.00,0:13:27.00,Default,,0000,0000,0000,,And the little one is really spongy.
Dialogue: 0,0:13:27.00,0:13:30.00,Default,,0000,0000,0000,,And the middle size one is really spongy.
Dialogue: 0,0:13:30.00,0:13:32.00,Default,,0000,0000,0000,,But what was interesting
Dialogue: 0,0:13:32.00,0:13:34.00,Default,,0000,0000,0000,,was the adult Triceratops was also spongy.
Dialogue: 0,0:13:34.00,0:13:37.00,Default,,0000,0000,0000,,And this is a skull that is two meters long.
Dialogue: 0,0:13:37.00,0:13:40.00,Default,,0000,0000,0000,,It's a big skull.
Dialogue: 0,0:13:40.00,0:13:42.00,Default,,0000,0000,0000,,But there's another dinosaur
Dialogue: 0,0:13:42.00,0:13:45.00,Default,,0000,0000,0000,,that is found in this formation
Dialogue: 0,0:13:45.00,0:13:48.00,Default,,0000,0000,0000,,that looks like a Triceratops, except it's bigger,
Dialogue: 0,0:13:48.00,0:13:51.00,Default,,0000,0000,0000,,and it's called Torosaurus.
Dialogue: 0,0:13:51.00,0:13:54.00,Default,,0000,0000,0000,,And Torosaurus, when we cut into it,
Dialogue: 0,0:13:54.00,0:13:56.00,Default,,0000,0000,0000,,has mature bone.
Dialogue: 0,0:13:56.00,0:13:58.00,Default,,0000,0000,0000,,But it's got these big holes in its shield.
Dialogue: 0,0:13:58.00,0:14:01.00,Default,,0000,0000,0000,,And everybody says, "A Triceratops and a Torosaurus
Dialogue: 0,0:14:01.00,0:14:03.00,Default,,0000,0000,0000,,can't possibly be the same animal
Dialogue: 0,0:14:03.00,0:14:05.00,Default,,0000,0000,0000,,because one of them's bigger than the other one."
Dialogue: 0,0:14:05.00,0:14:10.00,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:14:10.00,0:14:12.00,Default,,0000,0000,0000,,"And it has holes in its frill."
Dialogue: 0,0:14:12.00,0:14:15.00,Default,,0000,0000,0000,,And I said, "Well do we have any juvenile Torosauruses?"
Dialogue: 0,0:14:15.00,0:14:18.00,Default,,0000,0000,0000,,And they said, "Well no,
Dialogue: 0,0:14:18.00,0:14:21.00,Default,,0000,0000,0000,,but it has holes in its frill."
Dialogue: 0,0:14:21.00,0:14:24.00,Default,,0000,0000,0000,,So one of my graduate students, John Scannella,
Dialogue: 0,0:14:24.00,0:14:26.00,Default,,0000,0000,0000,,looked through our whole collection
Dialogue: 0,0:14:26.00,0:14:28.00,Default,,0000,0000,0000,,and he actually discovered
Dialogue: 0,0:14:28.00,0:14:30.00,Default,,0000,0000,0000,,that the hole starting to form
Dialogue: 0,0:14:30.00,0:14:32.00,Default,,0000,0000,0000,,in Triceratops
Dialogue: 0,0:14:32.00,0:14:35.00,Default,,0000,0000,0000,,and, of course it's open, in Torosaurus --
Dialogue: 0,0:14:35.00,0:14:38.00,Default,,0000,0000,0000,,so he found the transitional ones
Dialogue: 0,0:14:38.00,0:14:40.00,Default,,0000,0000,0000,,between Triceratops and Torosaurus,
Dialogue: 0,0:14:40.00,0:14:42.00,Default,,0000,0000,0000,,which was pretty cool.
Dialogue: 0,0:14:42.00,0:14:44.00,Default,,0000,0000,0000,,So now we know
Dialogue: 0,0:14:44.00,0:14:46.00,Default,,0000,0000,0000,,that Torosaurus
Dialogue: 0,0:14:46.00,0:14:49.00,Default,,0000,0000,0000,,is actually a grownup Triceratops.
Dialogue: 0,0:14:49.00,0:14:51.00,Default,,0000,0000,0000,,Now when we name dinosaurs,
Dialogue: 0,0:14:51.00,0:14:53.00,Default,,0000,0000,0000,,when we name anything,
Dialogue: 0,0:14:53.00,0:14:55.00,Default,,0000,0000,0000,,the original name gets to stick
Dialogue: 0,0:14:55.00,0:14:59.00,Default,,0000,0000,0000,,and the second name is thrown out.
Dialogue: 0,0:14:59.00,0:15:02.00,Default,,0000,0000,0000,,So Torosaurus is extinct.
Dialogue: 0,0:15:02.00,0:15:05.00,Default,,0000,0000,0000,,Triceratops, if you've heard the news,
Dialogue: 0,0:15:05.00,0:15:07.00,Default,,0000,0000,0000,,a lot of the newscasters got it all wrong.
Dialogue: 0,0:15:07.00,0:15:10.00,Default,,0000,0000,0000,,They thought Torosaurus should be kept and Triceratops thrown out,
Dialogue: 0,0:15:10.00,0:15:12.00,Default,,0000,0000,0000,,but that's not going to happen.
Dialogue: 0,0:15:12.00,0:15:17.00,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:15:18.00,0:15:21.00,Default,,0000,0000,0000,,All right, so we can do this with a bunch of dinosaurs.
Dialogue: 0,0:15:21.00,0:15:23.00,Default,,0000,0000,0000,,I mean, here's Edmontosaurus
Dialogue: 0,0:15:23.00,0:15:25.00,Default,,0000,0000,0000,,and Anatotitan.
Dialogue: 0,0:15:25.00,0:15:28.00,Default,,0000,0000,0000,,Anatotitan: giant duck.
Dialogue: 0,0:15:28.00,0:15:30.00,Default,,0000,0000,0000,,It's a giant duck-bill dinosaur.
Dialogue: 0,0:15:30.00,0:15:32.00,Default,,0000,0000,0000,,Here's another one.
Dialogue: 0,0:15:32.00,0:15:34.00,Default,,0000,0000,0000,,So we look at the bone histology.
Dialogue: 0,0:15:34.00,0:15:37.00,Default,,0000,0000,0000,,The bone histology tells us
Dialogue: 0,0:15:37.00,0:15:39.00,Default,,0000,0000,0000,,that Edmontosaurus is a juvenile,
Dialogue: 0,0:15:39.00,0:15:41.00,Default,,0000,0000,0000,,or at least a sub-adult,
Dialogue: 0,0:15:41.00,0:15:44.00,Default,,0000,0000,0000,,and the other one is an adult
Dialogue: 0,0:15:44.00,0:15:47.00,Default,,0000,0000,0000,,and we have an ontogeny.
Dialogue: 0,0:15:47.00,0:15:50.00,Default,,0000,0000,0000,,And we get rid of Anatotitan.
Dialogue: 0,0:15:50.00,0:15:53.00,Default,,0000,0000,0000,,So we can just keep doing this.
Dialogue: 0,0:15:53.00,0:15:55.00,Default,,0000,0000,0000,,And the last one
Dialogue: 0,0:15:55.00,0:15:57.00,Default,,0000,0000,0000,,is T. Rex.
Dialogue: 0,0:15:57.00,0:15:59.00,Default,,0000,0000,0000,,So there's these two dinosaurs,
Dialogue: 0,0:15:59.00,0:16:02.00,Default,,0000,0000,0000,,T. Rex and Nanotyrannus.
Dialogue: 0,0:16:02.00,0:16:04.00,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:16:04.00,0:16:07.00,Default,,0000,0000,0000,,Again, makes you wonder.
Dialogue: 0,0:16:07.00,0:16:10.00,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:16:10.00,0:16:12.00,Default,,0000,0000,0000,,But they had a good question.
Dialogue: 0,0:16:12.00,0:16:14.00,Default,,0000,0000,0000,,They were looking at them
Dialogue: 0,0:16:14.00,0:16:17.00,Default,,0000,0000,0000,,and they said, "One's got 17 teeth, and the biggest one's got 12 teeth.
Dialogue: 0,0:16:17.00,0:16:19.00,Default,,0000,0000,0000,,And that doesn't make any sense at all,
Dialogue: 0,0:16:19.00,0:16:21.00,Default,,0000,0000,0000,,because we don't know of any dinosaurs
Dialogue: 0,0:16:21.00,0:16:23.00,Default,,0000,0000,0000,,that gain teeth as they get older.
Dialogue: 0,0:16:23.00,0:16:25.00,Default,,0000,0000,0000,,So it must be true --
Dialogue: 0,0:16:25.00,0:16:28.00,Default,,0000,0000,0000,,they must be different."
Dialogue: 0,0:16:28.00,0:16:30.00,Default,,0000,0000,0000,,So we cut into them.
Dialogue: 0,0:16:30.00,0:16:32.00,Default,,0000,0000,0000,,And sure enough,
Dialogue: 0,0:16:32.00,0:16:35.00,Default,,0000,0000,0000,,Nanotyrannus has juvenile bone
Dialogue: 0,0:16:35.00,0:16:38.00,Default,,0000,0000,0000,,and the bigger one has more mature bone.
Dialogue: 0,0:16:38.00,0:16:41.00,Default,,0000,0000,0000,,It looks like it could still get bigger.
Dialogue: 0,0:16:41.00,0:16:43.00,Default,,0000,0000,0000,,And at the Museum of the Rockies where we work,
Dialogue: 0,0:16:43.00,0:16:45.00,Default,,0000,0000,0000,,I have four T. Rexes,
Dialogue: 0,0:16:45.00,0:16:47.00,Default,,0000,0000,0000,,so I can cut a whole bunch of them.
Dialogue: 0,0:16:47.00,0:16:50.00,Default,,0000,0000,0000,,But I didn't have to cut any of them really,
Dialogue: 0,0:16:50.00,0:16:53.00,Default,,0000,0000,0000,,because I just lined up their jaws
Dialogue: 0,0:16:53.00,0:16:56.00,Default,,0000,0000,0000,,and it turned out the biggest one had 12 teeth
Dialogue: 0,0:16:56.00,0:16:58.00,Default,,0000,0000,0000,,and the next smallest one had 13
Dialogue: 0,0:16:58.00,0:17:00.00,Default,,0000,0000,0000,,and the next smallest had 14.
Dialogue: 0,0:17:00.00,0:17:02.00,Default,,0000,0000,0000,,And of course, Nano has 17.
Dialogue: 0,0:17:02.00,0:17:05.00,Default,,0000,0000,0000,,And we just went out and looked at other people's collections
Dialogue: 0,0:17:05.00,0:17:09.00,Default,,0000,0000,0000,,and we found one that has sort of 15 teeth.
Dialogue: 0,0:17:09.00,0:17:12.00,Default,,0000,0000,0000,,So again, real easy to say
Dialogue: 0,0:17:12.00,0:17:14.00,Default,,0000,0000,0000,,that Tyrannosaurus ontogeny
Dialogue: 0,0:17:14.00,0:17:17.00,Default,,0000,0000,0000,,included Nanotyrannus,
Dialogue: 0,0:17:17.00,0:17:22.00,Default,,0000,0000,0000,,and therefore we can take out another dinosaur.
Dialogue: 0,0:17:22.00,0:17:24.00,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:17:24.00,0:17:28.00,Default,,0000,0000,0000,,So when it comes down
Dialogue: 0,0:17:28.00,0:17:30.00,Default,,0000,0000,0000,,to our end cretaceous,
Dialogue: 0,0:17:30.00,0:17:33.00,Default,,0000,0000,0000,,we have seven left.
Dialogue: 0,0:17:33.00,0:17:36.00,Default,,0000,0000,0000,,And that's a good number.
Dialogue: 0,0:17:36.00,0:17:39.00,Default,,0000,0000,0000,,That's a good number to go extinct, I think.
Dialogue: 0,0:17:39.00,0:17:41.00,Default,,0000,0000,0000,,Now as you can imagine,
Dialogue: 0,0:17:41.00,0:17:44.00,Default,,0000,0000,0000,,this is not very popular with fourth-graders.
Dialogue: 0,0:17:44.00,0:17:46.00,Default,,0000,0000,0000,,Fourth-graders love their dinosaurs,
Dialogue: 0,0:17:46.00,0:17:49.00,Default,,0000,0000,0000,,they memorize them.
Dialogue: 0,0:17:51.00,0:17:54.00,Default,,0000,0000,0000,,And they're not happy with this.
Dialogue: 0,0:17:54.00,0:17:56.00,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:17:56.00,0:17:58.00,Default,,0000,0000,0000,,Thank you very much.
Dialogue: 0,0:17:58.00,0:18:01.00,Default,,0000,0000,0000,,(Applause)