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Jack Horner and Hank talk about the evolution of dinosaurs, what it took to become a world-famous paleontologist, genetics, and meet a live dinosaur courtesy of Jessi Knudsen CastaƱeda.

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Hank: Hello, and welcome to SciShow Talk Show, it's that day on SciShow where we talk to interesting people about interesting things, and today, we have an amazingly interesting person. This is Jack Horner, who is a discoverer of several species of dinosaurs, professor at the Montana State University, and general kind of a bit of a legendary paleontologist. Groaned a little bit. Yeah, so what would you say you do?

Jack: I'm a glorified ditch digger.

Hank: So you dig.

Jack: I dig holes in the ground.

Hank: You have people dig holes in the ground.

Jack: Actually, I do that. I usually go find something and then have the graduate students dig it up.

Hank: Your--so, do you have any idea what your first dinosaur skeleton was?

Jack: The--yeah, the first dinosaur bone I found and the first skeleton I found were, well, the first bone was part of a duckbill dinosaur, and the first skeleton I found was the tail end of a duckbill dinosaur, and I think the first dinosaur I actually excavated was a duckbill dinosaur also, so I kinda like duckbill dinosaurs.

Hank: How did that go from just a, you know, a combination of luck and skill to a career?

Jack: Well, let's see, I uh, somehow graduated from high school.

Hank: Okay.

Jack: I got a D--- in English.

Hank: I didn't know they could give that many minuses.

Jack: Well, you know.

Hank: They just really wanted you to not--

Jack: They wanted me outta there, I guess, and but my senior year in high school, I did a science project on dinosaurs. I was looking--I was puzzled. I, you know all the time I was growing up in Shelby, um, close to Canada, I would go into Canada and look at their fossils and they had some great dinosaurs. And the ones that we were getting in Montana were awful. I mean it was just - and I was very interested why the dinosaurs were so cool, and so nice skeletons in Alberta, and crappy in Montana. And so I did a science project about that. And, and I won our science fair with it, and, and came here to Missoula for the state science fair and the geology department people were very impressed with it and so they invited me to come to study geology here at U of M.

Hank: Hmm, nice.

Jack: And-

Hank: Even with your D minus minus minus.

Jack: Well, they didn't know how bad my grades were.

Hank: (Laughs)

Jack: So I came to Missoula, um, and I was here - the first semester I flunked out. But then they just put, you know, you get to come the second or the second quarter because you're on probation, and then I flunked out that one, too. And then, and then I was drafted, and I went to Vietnam. Then I came back and I went promptly right back to college again with my 0.06 grade average.

Hank: (Laughs)

Jack: And uh...

Hank: Work up from there.

Jack: (Laughs) And uh, you know, I, I'm severely dyslexic, so that was the problem, but nobody knew what it was.

Hank: Right.

Jack: And I just really wanted to learn about fossils and they had a great program in paleontology here. And so, so I, I flunked all the classes, but I took them all and, and flunked out six more times. But I had a advisor who, he couldn't figure it out. He was like, you know, Jack does good with, you know, with studying things, but he just doesn't pass the tests.

Hank: Mhmm. Yeah.

Jack: And so he kept writing these letters to get me back into school and, and I just kept going until I had taken all of the classes.

Hank: (Laughs)

Jack: And then, uh-

Hank: At least taken them, not passed them.

Jack: I didn't pass any of them, no.

Hank: Okay. (Laughs)

Jack: But I took all of them, so I had really taken a lot of paleontology classes and some archaeology and - you know, basically everything I thought I needed to be a paleontologist. And then, I started applying for jobs in museums all over the world, where ever they spoke English I would get the address and send...

Hank: Mhmm.

Jack: And then uh, then I got a job at Princeton University as a technician, cleaning the fossils.

Hank: Right.

Jack: And that was 1975. And, uh, and so, in 1977, on vacation back in Montana I went back to the place I had found my first dinosaur bone, and I found a crushed egg, and it was the first dinosaur I had found in the Western hemisphere. Which was pretty cool.

Hank: Yeah.

Jack: And then, uh, a year later in the same area, uh, My friend Bob Macklin and I excavated the baby dinosaurs, um, near Choteau. And, and so I published my very first scientific paper in the Journal Nature, which is, was good.

Hank: Yeah, that's a, that's a good place to start.

Jack: Right. And so Princeton University then promoted me to research scientist.

Hank: Hmm.

Jack: And that's where my career started.

Hank: That's great. Um, so that, that find in Choteau -

Jack: Mhmm.

Hank: Um, what did that end up telling us about, dinosaurs in general?

Jack: Well, it, it was at a, it was sort of perfect timing. John Ostrom, a professor at Yale University had just, you know, a few years before, proposed that dinosaurs and birds were related.

Hank: Hmm.

Jack: And nobody believed it. I mean, people just could not get off this whole thing of, you know, birds and dinosaurs being related. So, so when the nest was found with babies in it that clearly had been cared for-

Hank: Mhmm.

Jack: It, it did a lot to sort of move the general public to understanding that dinosaurs and birds could be related.

Hank: Did you accept this idea that birds and dinosaurs were closely related pretty quickly or was that uh, like a, just you know

Jack: I...

Hank: -waiting for the evidence to tell kind of thing.

Jack: I uh, yeah I was, I was skeptical. But um, John Ostrom came to visit Princeton while I was there and he looked at the babies. And, and we agreed that they were babies. A lot of people, a lot of scientists didn't agree that they were babies.

Hank: (Laughs)

Jack: Because no one had ever seen a baby dinosaur before.

Hank: (Still laughing)

Jack: And so there were 15 of them in a nest-like structure

Hank: Yeah

Jack: And so, so he agreed and so

Hank: I, I do like the of idea of just tiny dinosaurs that just hang out 15 at a time and live in a nest together. They're adults though!

Jack: Right, yeah. It was just, it was just weird if you think about it

Hank: (Speaking at the same time) Just roommates!

Both: (Laugh)

Jack: You know, I, I was fortunate enough to find the first dinosaur embryo in the world and people had had dinosaur eggs from the 1800s

Hank: Mhmm.

Jack: And it never occurred to anyone to actually open one up and look inside.for

Hank: Well you don't wanna, you take this think that's been preserved for-

Jack: (Starts laughing)

Hank: tens of millions of years and cut it open!

Jack: Remember that glue is cheap!

Both: (Laugh)

Jack: It's just glue

Hank: Do you just, like, tap tap tap tap the egg away?

Jack: The first time I found a dinosaur egg I took a chisel and a hammer and busted it open

Hank: (Laughs)

Jack: But, you know, without busting it... I mean, just... Thing is, it's like having a birthday present or a Christmas present you never open because the package is so pretty. Right, I mean, that's the same thing, it's this weird preconceived idea that the egg is the precious thing, when in fact, the embryo inside is--

Hank: Of course.

Jack: --a lot more important.

Hank: So how--like, how did that process, like, a little chisel, I imagine? Like, how do you--how do you separate--?

Jack: The egg was this--about--the egg was about that big and the chisel was that wide.

Hank: Wow, okay.

Jack: I--you just--

Hank: Right down the middle.

Jack: Yeah.

Hank: And then, and just like--

Jack: Well, the first one I opened up didn't have an embryo in it, so I had to glue it back together.

Hank: I see, I see. You just put it back together.

Jack: Right.

Hank: Okay.

Jack: There's the third or fourth one that had the first embryo.

Hank: It's just--you're just a terror--

Jack: The first embryo in the whole world.

Hank: Just going around breaking dinosaur eggs. People must think you're crazy.

Jack: But so what, I mean--yeah, I tried to get the (?-8:54). They had a whole bunch of beautiful round eggs, and I asked them if we could just drop them on the floor and look inside. They didn't like that. CAT scanners didn't work very well in those days, so, you couldn't really CAT scan them. You can now.

Hank: So, you are also semi well-known for your quest to make a dinosaur or thoughts about how to make a dinosaur. Of course, we all know that all you have to do is get some amber with a mosquito inside, drill out the blood, and clone the dinosaur with this--with this tens of millions of year old blood.

Jack: Right. Yeah. That'd be great if it worked.

Hank: Or--how--so, first of all, we gotta say, in order to get a dinosaur, all you have to do is hatch a chicken egg. You have a dinosaur.

Jack: Right, exactly.

Hank: You go outside, you grab a pigeon, dinosaur. But if you want a dinosaur-looking dinosaur, what's your plans there? How do we do that?

Jack: In 1993, I had my graduate student, Mary Schweitzer and I tried, we got a National Science Foundation grant to try to extract DNA from a dinosaur, from one of our T-Rexes.

Hank: Okay.

Jack: And we discovered that DNA was just never going to be--we might find tiny, tiny pieces of it someday, but we were never gonna get enough to make a dinosaur.

Hank: Right.

Jack: And so we couldn't do what we do in Jurassic Park, so it started out as sort of a theoretical thing: could we make a dinosaur? And so just, you know, sort of looked into it and you know, because birds are dinosaurs and because they're the ancestral bird actually has a long tail and had arms, so I mean, basically, we just need to back up evolution and the way to do that is to use what we call atavistic genes, genes that are actually ancestral, that have been turned off.

Hank: Right.

Jack: All we had to do was find them and turn them back on again.

Hank: So a lot of times, evolution happens not by having a gene go from one form to another, but simply having a new gene take over and the old gene no longer expresses.

Jack: Exactly, right. And so that's what we've been looking for are these ancestral genes, and--

Hank: Right, so the genes for teeth, they didn't go away, they just stopped being expressed.

Jack: Well, the gene for teeth is still there, but the gene for enamel on the teeth is gone. So if you were going to actually put enamel back on the teeth of birds, you'd have to do it transgenically, in other words, take the enamel gene and put it back in the bird. But we can now produce a bird with teeth, and a group at Yale and Harvard actually figured out a way to change the snout from a bird-like beak back to a dinosaur-like snout, and our lab in Boseman is working on the tail.

Hank: Well, this is fascinating and I want to talk to you for hours and hours, but the episode has to be a certain length or else--but maybe, and I do get, luckily, for me, I do get to talk to Jack later tonight, so I've gotta save some stuff for that, but I would like to have a dinosaur join us. We could talk to a dinosaur about itself.

Jack: Okay, good.

Hank: Let's do that.

Jack: That's a good idea.

Hank: Hey!

Jessi: Hey!

Hank: Who's this?

Jessi: This is Hara, she's a Harris's Hawk.

Hank: Oh, I see.

Jessi: Yeah. Say that five times real fast.

Hank: Hara the Harris's Hawk.

Jessi: Yeah.

Hank: That was easy to do it once.

Jessi: Yeah, you did good.

Hank: Are they the kind that sometimes perch on top of each other.

Jessi: They are! Yeah!

Hank: I saw that on the internet.

Jessi: Yeah, these guys are really cool. They're not just ordinary hawks, they're--they have really neat behaviors. They have two really neat behaviors, actually.

Hank: Okay.

Jessi: So they stack, and the other one rhymes with that.

Hank: Is that--so they stack so that they can, like, there just aren't enough perches around so just each other?

Jessi: Well, kinda, yeah, like, there's gonna be--they live in the desert, they're desert birds, so there's gonna be, you know, few ideal perches, and so if a lower, on the hierarchy, one goes and finds a good perch and then she comes along and she's like, that's my perch.

Hank: Yeah.

Jessi: They'll move, she'll land there, and they'll be like, whoa-kay, I'll sit right on top of you. So it's the more dominant one, which is the alpha female, she's in charge, always the females in charge, and then there can be an alpha male as well and a beta female and beta male, so...

Hank: So they're more--actually, I remember why I ended up looking at this, because I was curious if any birds of prey hunted in packs.

Jessi: Yeah, you got the rhyming word!

Hank: Yeah.

Jessi: Yeah, so they stack and they hunt in packs.

Hank: Oh, okay.

Jessi: Yeah, yeah. So the focus word is that they hunt in packs, so other raptor type birds like this, they eat in groups, but these guys actually cooperatively hunt, which is really cool.

Hank: That's really cool.

Jessi: Reminds me of Velociraptors, absolutely.

Jack: Yes.

Hank: Yes.

Jessi: Yeah.

Hank: I would be concerned about even something that size with a snout and teeth.

Jessi: Yeah, that's slightly--that's terrifying, because these guys, I mean, I obviously would not be holding her this close.

Hank: Well, even that beak is something.

Jessi: Actually, these guys don't attack with their beak at all. I mean, they use it to eat.

Hank: They eat with a beak.

Jessi: They eat with it, yeah, it is pretty sharp there to puncture and rip pieces off, but if they're being attacked or they want to attack, they actually move their head out of the way. They want to use these--

Hank: Those do look like trouble, yeah.

Jessi: Yeah, which is--'raptor' means 'seizing', and so to seize something, and so they use these amazing talons that they have down here, really really strong and sharp, which is why you have to wear thick leather to make sure--I mean, she's flown past me sometimes and she'll just, you know--

Hank: Graze you.

Jessi: Graze me, and it'll bleed, I mean, they're super sharp. So that's what she uses to attack and defend herself--is those, those talons there, which I think is really cool because, I mean, they've adapted so much, they have a lot of the same features as dinosaurs.

Jack: That's where they got all those features.

Hank: Yeah.

Jessi: Yeah.

Jack: Their ancestors gave them--you know, one of the things I've been working on lately suggests that, you know, other than flight, basically every characteristic that birds have, they got from their ancestors, the dinosaurs, and it might even be in the way that they kill things, you know, lions and tigers and cheetahs and so forth will actually kill their prey. They actually go up and they'll bite out the throat, they'll do anything, and they wait 'til the animal is dead. Birds don't do that. They actually knock 'em down, stand on them, and eat 'em alive.

Jessi: Yeah.

Jack: And we think raptor--raptorial dinosaurs, did the same thing. Not by standing on them, necessarily, but literally scaling their prey and using their claws, which are recurved, I mean, they could literally have--you just don't even want to think about it, I mean, they would just literally disembowel their prey.

Jessi: Yeah, like reas and emus.

Jack: But they would be standing on them, eating them, while they're alive.

Jessi: Fun. I've seen that. I've seen a dinosaur in action.

Jack: I know, I know.

Jessi: Yeah, it's really--and then, these wings, you were saying that that's pretty much the only thing that these guys have--I mean, they've lost a lot of things, they've lost that tail that dinosaurs have and they've lost the actual grasping hands, they've turned into wings, um, but recently, I think it's really cool, the very tip of their wing--so they're in like, dino-birds, that used to be able to flutter and glide and stuff, not the pterosaurs but the actual, uh, gliding dinosaurs, um, so they--these guys, birds, modern day birds, have this really neat, their thumb has adapted for extra specialized flight. It's called the alula, and the alula allows them to navigate very easily in slow flight, so that they can go between trees and they can do a nice pretty landing. So it's like, it's like your thumb curled up just a little bit to put it in a nice little landing, which is one of the newest things that birds have developed.

Jack: Gliding.

Jessi: Yeah.

Jack: And that's one of the reasons that, you know, we're pretty sure that flight started with flapping rather than gliding, and that gliding came along later.

Hank: Interesting.

Jessi: Yeah.

Hank: So is it just like a way to jump higher? Basically?

Jack: No, it's actually a way to slow down if you're jumping from the trees down.

Hank: Oh, okay.

Jack: Right, and you just flutter yourself down, and the, you know, as your fluttering gets better, you actually can go somewhere.

Jessi: Go further. I thought it was also to help go up a steep hill, too.

Hank: Yeah, I heard about that.

Jack: Well, yeah, they--I think Ken Dial talks about them, things like that.

Jessi: Okay, yeah, yeah.What do you think, Hara, you're looking around again. Do you want to try and perch on someone else's arm?

Hank: I don't know.

Jessi: Are you answering for her?

Hank: I--yeah, I don't want to make her more uncomfortable than she already is.

Jessi: She's actually, she's pretty calmed down now, she's doing a really good job. She was unsure at first. Do you want to try, Hara? Alright, are you ready, Hara? Are you ready for this? Alright. You put your glove out, she'll step right on there.

Hank: Oh, yeah, you got almost, a little--alright, don't flap on me. I see your thumbs.

Jessi: You're fine. You're fine. Yeah, you see those? She's holding--I like that she did that, those alulas there, because she actually has damaged wings, which is why we have her, and the reason that she can't fly in the wild is because she doesn't have those feathers and it's damaged right on the alulas, the very tip there, so she can't catch prey on her own, and she's a pretty terrible lander as well.

Hank: So are these brow ridges, these beautiful, grumpy brow ridges, like, basically baseball caps?

Jessi: Birds of prey have this because they're gonna be flying and they have to look very precisely. These guys, they say they have such good vision, if you wanna compare it to a human, that they could actually read the print on a newspaper from across a football field. I mean, so they're flying way high in the air and they can see a little tiny mouse down on the ground, they can dive down there, but they really wanna make sure that they don't get any glare in their eyes, so yeah, exactly, keeping the sun out of their eyes. Look, she's doing so good.

Hank: This is a not insubstantial bird.

Jessi: I'll take her back. Yeah, you wanna guess how much she weighs?

Hank: Um, I don't know, three, four pounds?

Jessi: Yeah. She weighs just about three pounds. Ready? There it is. Did she get you in the face?

Hank: A little bit. Just a feather.

Jessi: Good girl. Jack, do you want to try holding her?

Jack: Sure.

Jessi: I'll let you escape over there for a little bit. I know.

Hank: It's a lefty.

Jessi: Good girl.

Hank: I'm gonna go down.

Jessi: Yeah. Alright, so you put your arm right in front of mine and above mine. Let's try it one more time. There ya go. Good girl. Yeah, it's a fine perch, huh? There you go. I know. So, she's panting right now, that's because she does not fly for a living, she sits for a living, and so just a little bit of flapping is--she's gonna be out of breath, and so she is trying to catch her breath like we would, and she pants, as you can see, she's actually sticking her tongue out a little bit, and that helps cool her down.

Jack: She's got a breathing apparatus that's a lot better than ours.

Jessi: Yeah, yeah, they do. That's the other--did dinosaurs have the one-way breathing?

Jack: Yes.

Jessi: They did? That's awesome!

Jack: Yes. Every characteristic that birds have, dinosaurs had before them, except the flight feather.

Jessi: Okay. Okay.

Hank: So I don't know about this one-way breathing thing that you're talking about.

Jessi: It's--it's--

Hank: Tell me.

Jessi: It's really cool, it's way more efficient than we breathe. So we inhale, and then we have to exhale, right?

Hank: Yeah.

Jessi: 'Cause we have just these one set of lungs that just go in and out. So these guys actually have air sacs that go throughout their body, and so they can inhale and exhale at the same time. Can you explain it in more detail than that?

Jack: Well, that's the best explanation. They basically, yep, they--because there's a bunch of air sacs and they have them in their vertebrae, they have them in their--between their ribs, they can--as air is coming--as oxygen is coming in through the lungs on its way to the air sacs, air in the air sacs is coming back out and going through the lungs as well, and so they always have fresh air in their lungs.

Jessi: Which is how they can sustain flight for so long.

Hank: Yeah, yeah.

Jessi: So dinosaurs were a lot heavier, they had hollow bones, and then birds also have hollow bones, but they've gotten even thinner and then they've lost so much weight with the thinning of the bones, and then the air sacs allow them to fly. So everything has just specialized and specialized and specialized so that they can fly.

Jack: But when we find little Velociraptor-like dinosaurs, we--it's really hard to tell if we have a bird or a dinosaur, I mean, we can't really always tell, unless you can find the arm to see if it was long enough for a wing, because the primitive birds had long tails as well.

Hank: So Hara, thank you, you wanna look at the people and say--yeah, right, like, that was a good--you follow directions really well. Thanks for joining us. Jessi, thanks for bringing her in. Jack, it's just been an absolute pleasure to talk to you, so fascinating, great--so much knowledge to share.

Jack: My pleasure.

Hank: I very much appreciate it, and thanks to all of you for watching, thanks to everybody for helping shoot this. If you like this and you want to support us, I would very much appreciate it if. If you're interested in looking at, where we have fan-funding going on, thanks to all of our Patrons out there, and if you wanna just keep watching SciShow, you can go to and subscribe.