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Bringing Dinosaurs Back From Extinction


Those who saw Jurassic Park might be wary of the idea of resurrecting dinosaurs from extinction. However, one scientist claims that this idea is not only possible, but he knows how to do it. We speak with the author of "How to Build a Dinosaur," a book that claims extinction doesn't have to be forever.

Event: Jack Horner Lecture 'The Changing Faces of Dinosaurs'

  • San Diego Natural History Museum, 1788 El Prado, Balboa Park, San Diego
  • Tuesday, April 13, 2010
  • 6 p.m.
  • Age Requirement: All ages
  • Cost: Free - $16

Full Event Information

Jack Horner will be discussing the "Changing Faces of Dinosaurs" tonight at 6 p.m. at the San Diego Natural History Museum.

MAUREEN CAVANAUGH (Host): I'm Maureen Cavanaugh, and you're listening to These Days on KPBS. Evolution is only supposed to work one way, moving forward in time. It's supposed to make species better adapted to their environment and better able to survive. But what if you could turn the clock back on evolution and get a living glimpse of species that didn't make it to the 21st century, perhaps to see a bird move back on the evolutionary scale to its ancient past as a dinosaur. This may all sound a little too much like science fiction, like "Jurassic Park," in effect, but there is actually an effort underway in real science to create a bird that is, in effect, its own evolutionary ancestor. With us to explain the hows and whys of the project is my guest, Jack Horner. He’s Regent's Professor of Paleontology at Montana State University, curator of paleontology at the Museum of the Rockies, and author of "How to Build a Dinosaur: Extinction Doesn’t Have to be Forever.” Dr. Horner, welcome to These Days.

DR. JACK HORNER (Paleontologist): Thank you.

CAVANAUGH: And we’d like to invite our listeners to join the conversation. If you have questions about this remarkable scientific idea, give us a call. The number is 1-888-895-5727, that’s 1-888-895-KPBS. Now, as I said, this idea, on the surface, sounds a lot like “Jurassic Park” but the science is very different. So tell us what you’re proposing.

DR. HORNER: Well, it is. You know, in “Jurassic Park” the whole idea was to clone a dinosaur, basically. You know, go out and find a insect embedded in amber…


DR. HORNER: …that had bit, you know, taken some – drawn some blood from a dinosaur and then clone it. And, as you can imagine, that’s – If you did go out and find a insect in amber and you got something out of the insect in amber and cloned it, chances are you’d get yourself a mosquito. That’s…

CAVANAUGH: Okay. All right. Yeah.

DR. HORNER: So, you know, and we actually have learned the hard way, looking for dinosaur DNA that it probably just didn’t last that long. I mean, at – we’ve been looking for DNA for a long time in dinosaurs, in insects, in all sorts of things and we have not found any. So…

CAVANAUGH: And you make the point in your book that the whole idea of finding dinosaur DNA and recreating dinosaurs in that way, really hasn’t kept up with the times because what is now really sort of exciting people is the idea of evolutionary developmental biology or what people call Evo-Devo.

DR. HORNER: Evo-Devo, yes.

CAVANAUGH: What is this?

DR. HORNER: Well, instead of going after the dinosaur DNA from an extinct dinosaur, we’re going at trying to just use the animals that dinosaurs gave rise to, and those are birds. So birds are the evolutionary descendents of dinosaurs and so they carry dinosaur DNA.

CAVANAUGH: I see what you’re saying. So while I was reading your book, “How to Build a Dinosaur,” it reminded me—and tell me if I’m wrong—of some of the pictures that we have seen in biology class and so forth of a development – a developing human fetus and the fetus seems to go through a time when it looks more like a fish or when it looks more like a…

DR. HORNER: Exactly.

CAVANAUGH: Is that what you’re talking about, that kind of evolutionary development as part of a living species right now?

DR. HORNER: That’s exactly right. If we – It’s true, I – All embryos, all vertebrate embryos…


DR. HORNER: …go through changes that look very similar not necessarily to an adult fish or something like that. It actually looks like the embryonic fish. So there is a point in time where a bird actually has the characteristics of a reptile yet has – and as it continues to develop, just like humans, at a point in our development, we have a tail, we have, you know, we have these, you know, quote, fish-like characters.

CAVANAUGH: Right, right.

DR. HORNER: And then genes kick on and turn off and we end up being the way we are. In the development of a bird, it’s also doing the same thing and there is a point in time it has a long tail and it has – it starts out with a five-fingered hand and then a gene kicks on that takes two of the fingers out and then it has three fingers and then those three fingers fuse together to make a wing. So the project really, you know, we’re – There’s a lot of people that are interested in seeing, in studying, how basically the evolutionary process between dinosaurs and birds happened. So how, you know, how the tail reduced, how the hands – how the arms and hands became wings and so on and so forth. And so, you know, I thought, well, if you can figure that out, all we have to do is just stop some of those genes from happening and we can, you know, in effect, reverse evolution.

CAVANAUGH: I’m speaking with Dr. Jack Horner. He is the author of "How to Build a Dinosaur." And we’re taking your calls about this remarkable idea at 1-888-895-5727. Before we go into why perhaps anyone would want to do this, how would you stop this evolutionary process, let’s say, in an egg or when, you know, when a bird is a little embryo bird, while allowing the maturation of this living entity, you know, to allow him to actually hatch?

DR. HORNER: Well, we don’t, you know, any – The projects that are going on, nothing hatches.

CAVANAUGH: Nothing hatches.

DR. HORNER: Nothing hatches. Basically what we’re looking for is just a few very select genes. As the tail develops in the bird, there’s a point at which a gene turns on and resorbs the tail, in other words gets rid of it. And all we have to do is stop that gene from turning on, and we’ll get a bird that hatches out with a tail.

CAVANAUGH: Now you’ve dubbed this creature that doesn’t exist a word, what do you…?

DR. HORNER: Dinochicken.

CAVANAUGH: Dinochicken.

DR. HORNER: Well, yeah, chickens are easier to come by than most birds, so…

CAVANAUGH: Or a chickenosaurus.

DR. HORNER: Chickenosaurus, yes.

CAVANAUGH: Now what would a chickenosaurus look like? Obviously, it would have a tail.

DR. HORNER: Well, what we’re – The simplest genes to find, one of them is teeth and there’s a group in Wisconsin that’s actually found that gene, so you can actually get a chicken with teeth.

CAVANAUGH: They’ve created a chicken…

DR. HORNER: They’ve created a chicken with teeth. And, you know, they – there’s a lot of other things. You know, they make chickens without feathers and, I mean, there’s a whole bunch of things you can do but, of course, dinosaurs had feathers so there’s no reason to have a, you know, naked chickenosaurus.

CAVANAUGH: Well, that’s good, I’m…

DR. HORNER: But, you know, just the simplest things of all. Like I say, you know, actually a bird is a dinosaur. Technically speaking, a bird is a dinosaur so you don’t have to do anything to build a dinosaur because we already have them. But, you know, esthetically looking, esthetically speaking, they don’t look like a dinosaur and so if a bird had a long tail and it had arms and hands instead of wings, and teeth, it would esthetically look more like a dinosaur. And so that’s – that’s sort of what we’re headed for, is just three simple things: a tail, hands, teeth.

CAVANAUGH: Now would you be trying to, in a sense, regress this bird, this chicken to a specific type of dinosaur?

DR. HORNER: No. No. But, you know, once people understand genetic engineering, that’s certainly something that they could certainly think about doing sometime. But, you know, that’s definitely in the distant future.

CAVANAUGH: Define for us atavism.

DR. HORNER: Well, that’s the tail, the hand, the – that’s the…

CAVANAUGH: These characteristics…

DR. HORNER: …the characteristics that we’re trying to regain.

CAVANAUGH: Uh-huh. And so how would creating this dinochicken help in our understanding of evolution? Would it, in effect, sort of – I know this is redundant to scientists but would it sort of, in effect, prove evolution?

DR. HORNER: Well, it certainly, you know, if you can make it go backwards, it certainly must’ve come forward. I mean, it’s, you know, it’s – You know, there’s so much proof of evolution that, you know, that’s certainly…

CAVANAUGH: That’s not your goal.

DR. HORNER: …don’t need any – don’t need anything like this but…

CAVANAUGH: That’s not your goal.

DR. HORNER: Right.

CAVANAUGH: Would it help us understand dinosaurs any better?

DR. HORNER: And it – Not necessarily, no. No, I – You know, the – In all of these kinds of studies, the idea really is just to learn how to turn on and off genes and gain something, benefit something, from that knowledge. If we, you know, can target certain genes, turn the – and know how to turn them on and turn them off, obviously there are a lot of genetic diseases that we can have the potential of solving. So it’s – you know, it’s sort of a fun way of just learning how to manipulate genes.

CAVANAUGH: I’m speaking with Jack Horner. He’s Regent's Professor of Paleontology at Montana State University, curator of paleontology at the Museum of the Rockies, and author of the new book, "How to Build a Dinosaur." We’re taking your calls at 1-888-895-5727. Julie is calling us from Encinitas. Good morning, Julie, and welcome to These Days.

JULIE (Caller, Encinitas): Hi. I have a question for you. This is going back in my education a bit but you hear that during the replication process there’s sometimes some damage to genes and then that can lead to a change that, you know, is a small step in the path of evolution. But I was wondering, is there any research specifically into maybe how the environment might have changed and a new chemical might’ve entered the environment that might’ve damaged a gene and thus leading to these sort of small evolutionary changes that might’ve turned a gene on or off?

CAVANAUGH: Thank you, Julie.

DR. HORNER: Well, obviously those are the kinds of things that people who are trying to study evolutionary change in things like fruit flies are always, you know, pushing this and pushing that and messing with the environment and trying to get things to happen. The changes that – You know, evolution is a funny thing. All of the changes that occur, occur between the parent and the offspring, those are the greatest changes that ever happen. And we see evolution over very long periods of time when we can, you know, go, you know, follow through, you know, hundreds or thousands of generations. Evolution, evolutionary change does not happen quickly.

CAVANAUGH: Now is it the main scientific challenge in making this idea a reality the ability to turn on and off genes?


CAVANAUGH: And how have people managed to do that in that chicken with teeth, for instance?

DR. HORNER: Well, that’s – In order to, you know, in order to flip the switch, you just – you get a – you have a gene that – you have one gene that turns on another gene basically.


DR. HORNER: Or turns it off.

CAVANAUGH: And that’s discovered through painstaking…

DR. HORNER: Right, yeah.

CAVANAUGH: …scientific research.

DR. HORNER: Yes, it is.

CAVANAUGH: Okay. What are some of the ethical issues that you’ve encountered in this project? I know on the back of your book, you basically say that this is an adventure. This is basically a, although that there are scientific projects that are underway towards this end. As you say, there’s nothing ready to hatch in the laboratory yet so this is a sort of an idea, an adventurous idea at the moment. What is some of the blowback you’ve been getting from people when they hear about this project and perhaps they aren’t comfortable with it?

DR. HORNER: Well, yeah, there’s a big difference between my project and everyone else’s project. There are a lot of people really working on trying to figure out how it is that, you know, that dinosaurs gave rise to birds and how they – you know, how dinosaurs lost their tail, basically. And so I’ve always thought, well, you know, soon as we figure that out, then we just can go backwards and, you know, stop that gene and just have a chicken with a tail. The – It’s something that, you know, we would do just in an egg and, you know, before we even thought about hatching it we would find out if there was any repercussions to it.

CAVANAUGH: Right, right.

DR. HORNER: I mean, there are certainly some mechanical difficulties with it. One of the things for sure, as birds have evolved, they’re – you know, from dinosaurs, dinosaurs’ legs were directly underneath them just like ours are. And birds, if you ever watched a bird walk around, it looks like its knees are bending the wrong way…

CAVANAUGH: Umm-hmm, yes.

DR. HORNER: …because that’s it’s ankle.


DR. HORNER: So its knee, you know, the thigh, when you’re eating chicken, the thigh is drawn up and it’s parallel to the ground and so you don’t actually see the thigh, you don’t see the thigh bone as a chicken’s walking around or any bird’s walking around. So – And the reason the thigh bone is parallel to the ground is it actually has pushed the center of gravity forward because there is no tail. So if you add a tail, then all of a sudden the bird can’t balance anymore. And so you would actually have to figure out how to get the thigh bone back underneath the body.

CAVANAUGH: So there would be a number of changes that you’d have to make in order to make even the birth of such a creature a humane act.

DR. HORNER: Exactly.

CAVANAUGH: And that would be very important to you, to make sure that it’s…

DR. HORNER: Certainly.

CAVANAUGH: …there was no harm done to this creature…

DR. HORNER: Right.

CAVANAUGH: …that was about to be born.

DR. HORNER: Right.

CAVANAUGH: But what…


CAVANAUGH: Yeah, go ahead.

DR. HORNER: …not only – Another thing to remember is you only make them one at a time.


DR. HORNER: They’re only made one at a time. You can’t – This is not changing DNA so, you know, you – if you were to mate a dinochicken with a regular chicken, you’d still end up with a chicken.

CAVANAUGH: Gotcha. Okay. Let’s take another call. Phil is calling us from Clairemont. Good morning, Phil, and welcome to These Days.

PHIL (Caller, Clairemont): Oh, good morning. There’s a three-word phrase that I’ve been trying to remember for years. It’s basically talking about embryology recapitulates the evolutionary process. So do you know what that three-word phrase is?

DR. HORNER: Ontogeny recapitulates phylogeny.

PHIL: Ontogeny recapitulates – what’s the third word?

DR. HORNER: Phylogeny.

PHIL: Phylogeny.

CAVANAUGH: How could you forget that, Phil?

PHIL: Yeah, you know?

DR. HORNER: In other words, growth recapitulates evolution.

PHIL: Okay, so I’ll just say embryology recapitulates evolution.


PHIL: That makes it easier to remember. All right, thank you very much.

CAVANAUGH: Thank you for the phone call. How would – if you could, if this project succeeds in any way, how does this help humans?

DR. HORNER: Well, like I said, it’s – it’s about learning how to flip genes on and off. It’s kind of the fun way of figuring that out. But there are an awful lot of genetic diseases in the world and a lot of them have to do with the spine, spinal diseases. And once we figure out, you know, the genes that are involved in actually lengthening the tail, which has, you know, spinal cord in it, we will have figured out probably how to fix some of those things.

CAVANAUGH: What do you think fascinates people so much about dinosaurs?

DR. HORNER: Well, I think it’s – You know, I don’t know that adults actually are fascinated by them. I think their children tell them they have to be. Little kids love dinosaurs and I think it’s because they’re, you know, dinosaurs were big and different and they’re gone. Adults, if you ever – if you look at when adults are interested in dinosaurs, it’s usually, you know, has something to do with movies, when, you know, “Jurassic Park” got the interest in adults pretty high. But kids are interested all the time and, I don’t know, it’s…

CAVANAUGH: You have a really great scene that sort of ends your book and that is your fantasy of a lecture involving a new creature. Tell us about that.

DR. HORNER: Well, I just, you know, I create this dinochicken and, you know, I don’t have to give lectures anymore. I can just take him onto stage and that will be it.

CAVANAUGH: You say that if it was as big as a emu that he would have to have handlers. And…

DR. HORNER: Well, you know, you could do it with any bird. I mean, if you can do it with a chicken, you can do it with an ostrich. So, I would – I – You know, I’m reminded of Mary Shelley’s book, “Frankenstein.” So, I – you know, rather than making a monster that, you know, is big enough to eat you…


DR. HORNER: …you’re probably better off just to make a little – little bitty chicken.

CAVANAUGH: Do you have any concerns about the way this research is going?

DR. HORNER: Concerns? No, not really. I mean, it’s – you know, everything is very simple. You know, there’s nothing – Like I said, it’s – these are esthetic changes. You know, it’s kind of like, you know, doing a little genetic manipulation to have somebody with blue eyes rather than green eyes. I mean, that – They’re – We’re still – we’ll still have chickens.

CAVANAUGH: We’ll still have chickens. Well, you know, I want to thank you very much for speaking with us today and I also want to make sure that people know that you’re going to be in – you’re here in San Diego to discuss the "Changing Faces of Dinosaurs" at the San Diego Natural History Museum. That’s tonight at 6:00 p.m. Dr. Horner’s lecture is part of the new exhibit at San Diego’s Natural History Museum called “Dinosaurs: Ancient Fossils and New Discoveries,” which also includes a 3-D movie called “Dinosaurs Alive.” And once again, Dr. Horner’s lecture tonight is about the "Changing Faces of Dinosaurs," that’s at six at the San Diego Natural History Museum. For more information, you can go to our website, Dr. Horner, thank you so much.

DR. HORNER: You’re very welcome.

CAVANAUGH: And if we didn’t take your question on the phone, please do go online, Coming up, we’ll hear about UCSD’s incredible brain dissecting webcast. That’s as These Days continues here on KPBS.

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