The “Science” of Zombies and the Walking Dead, with Robert Kirkman

What can we learn about anthropology and physiology from zombies? Neil Tyson interviews “The Walking Dead’s” Robert Kirkman, anthropologist Jeffrey Mantz, Harvard prof. Dr. Steve Schlozman, co-host Maeve Higgins, Chuck Nice, Mona Chalabi, and Bill Nye.

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:01Neil deGrasse Tyson?

  Welcome to StarTalk. Your place in the universe where science and pop culture collide. StarTalk begins right now.

• 0:22Neil deGrasse Tyson?

  Welcome to the American Museum of Natural History. I'm Neil deGrasse Tyson, your personal astrophysicist, and tonight on StarTalk, we're gonna talk about the zombie apocalypse. And we're gonna feature my interview with Robert Kirkman, who is the creator of the hugely popular TV series, The Walking Dead. We're gonna find out what makes zombies so creepy and what we should all do to prepare for the zombie apocalypse. Let's do this!

• 0:55Neil deGrasse Tyson?

  I got with me here Maeve Higgins. Maeve! Hi! My co-hosting comedian, and we have with us a professor of anthropology, Jeffrey Mans. Jeffrey, thank you for coming up! You came up from Washington, you're a professor at George Mason University. Now, we did some homework on you, you actually taught a course on zombies. And so, can you tell me what anthropology has to do with zombies? I mean, professionally, speaking.

• 1:20Speaker 01

  Quite a bit. So it's just, the course was just basically a gimmick for teaching different ways of thinking about how societies deal with fear, how they deal with things that are sort of foreign to it, or that are out of the ordinary.

• 1:33Neil deGrasse Tyson?

  So zombies were a hook for you?

• 1:34Speaker 01

  Or zombies were a hook.

• 1:36Neil deGrasse Tyson?

  Yeah. And so, depending on how zombies are treated in storytelling, they are either the main story, or how the rest of us react to one another becomes a story. And that's where you come in.

• 1:49Speaker 01

  Yeah, that's where I come in.

• 1:50Neil deGrasse Tyson?

  Okay, and so, do you also teach about the origin of zombies?

• 1:54Speaker 01

  Yeah, I did, I do quite a bit on that.

• 1:56Neil deGrasse Tyson?

  What is that? I mean, I hear it's, is it like Haitian voodoo, is that right?

• 2:00Speaker 01

  So, the term came from Africa, there's debates about where it came from, but it was probably from the Congo, from a key Congo word, or another West African language word. It was imported into Haiti, probably at the... End of the 18th century and then flourished into a full-blown, what they call syncretic religion. It brought in parts of Catholicism, parts of West African religion.

• 2:23Neil deGrasse Tyson?

  So syncretic, you mean it synthesizes?

• 2:24Speaker 01

  Yeah, it synthesizes.

• 2:26Neil deGrasse Tyson?

  It's a one thing that matters to that culture at that time.

• 2:28Speaker 01

  Yeah, yeah.

• 2:29Neil deGrasse Tyson?

  So that's cool. So dead people rise up and hang out in Haiti, is this what you're saying?

• 2:35Speaker 01

  Actually, no. So the idea of a revenant corpse, a corpse that comes back to life, actually probably comes...

• 2:43Neil deGrasse Tyson?

  Wait, wait, wait. There's a word for a corpse that comes back to life?

• 2:47Speaker 01

  Yeah.

• 2:47Neil deGrasse Tyson?

  Revenant?

• 2:48Speaker 01

  Yeah, from the French, revenant.

• 2:50Neil deGrasse Tyson?

  That doesn't help me.

• 2:51Speaker 01

  No.

• 2:53Neil deGrasse Tyson?

  Revenant from revenant?

• 2:54Speaker 01

  It's spelled revenant.

• 2:56Neil deGrasse Tyson?

  I need some more help here. What does the word, what does the word mean?

• 2:58Speaker 01

  So a lot of West, a lot of European, particularly Northern European folklore, has some figure of, of the dead that comes back to life. Either usually because they lived a bad life, or they were, they died badly.

• 3:14Speaker 02

  Like a ghost?

• 3:15Speaker 01

  Like, they're kind of like a ghost.

• 3:17Speaker 02

  Like a banshee.

• 3:18Speaker 01

  Except they come back in a corporeal form, which is worse. You know, ghosts can be relatively harmless.

• 3:24Neil deGrasse Tyson?

  Your ghosts are spiritual, right? They pass through things. But if you're a physical thing, and you're dead, yeah, that's...

• 3:30Speaker 01

  This is, you find this throughout Europe. That's actually why we stick nails in coffins. I mean, like, why are you, what are they gonna, you know, run away or something?

• 3:38Neil deGrasse Tyson?

  No, no, but it's a little, it's a little, rather than just dumping the body in the thing, you put it in a box.

• 3:43Speaker 01

  Yeah, but why?

• 3:43Neil deGrasse Tyson?

  But you don't want the box to accidentally pop open, so you put it, you nail it shut.

• 3:47Speaker 01

  Have you seen how many nails they put in those?

• 3:48Neil deGrasse Tyson?

  Yeah, it seems more than was necessary, I agree.

• 3:50Speaker 02

  And if the person was unpopular, there's like more nails.

• 3:53Speaker 01

  Yeah, more nails.

• 3:55Neil deGrasse Tyson?

  Just to make sure.

• 3:57Speaker 02

  But I, so I heard that, that, you know, the idea of zombies originally came from Haiti. But was there zombies, or what, what, what was the thing that was there?

• 4:07Speaker 01

  So zombies in Haiti, what are called zombies and were popularized by the Wes Craven's adaptation of a book called Serpent in the Rainbow, are sort of these, historically those figures are slaves, they are kind of, you know, put into trances and made to do certain sorts of things. The early American zombie films, like the 1932 film, Victor Halperin directed called White Zombie, actually kind of more closely depicted that. In 1968, it shifts to this new figure, which actually for a while, and after 1968, they weren't called zombies, they were, you know, Romero didn't call them anything, but that's when the modern zombie sort of emerged.

• 4:52Neil deGrasse Tyson?

  So it's been in our culture ever since anyone's thinking about the culture, in movies, in TV, just lore in general. And so, The Walking Dead is the most successful TV series ever, right?

• 5:06Speaker 02

  Like the most watched show on cable.

• 5:08Neil deGrasse Tyson?

  Yeah, on cable, that's cable I should have said, to qualify that. And I sat down with the creator of that show, the creator, Robert Kirkman. He wrote the graphic novels on which The Walking Dead is based. And I asked him, just, "Why is this the most popular show on cable? What's up with that?" Check it out.

• 5:29Speaker 03

  What I did is I made it so proper. I was like, "What if people kiss while zombies are trying to eat them?" And then people were like, "I like this romance stuff."

• 5:38Neil deGrasse Tyson?

  There's some relationships, really.

• 5:39Speaker 03

  Yeah, I mean, I don't know, I'm interested in that kind of stuff. I mean, I'm a huge fan of zombie lore and zombie stories, and there had never been, you know, the zombie movie that never ends, you know, is what I've always said Walking Dead is. There'd never been a story that focused on the characters and showed how they lived from year to year to year after the fall of civilization. You know, most zombie stories are about the initial outbreak and things happen and they try to survive and they live in a place for a while and then they all die or they all ride off into the sunset, you never see them again. And to me, you know, not only like...

• 6:15Speaker 03

  Like, seeing people try to find food and try to build shelter and try to protect their families. That stuff's very fascinating, but also like, living in these extreme situations and just changing fundamentally how we interact with each other and how we relate to each other and, you know, because in The Walking Dead, it becomes very scary very quickly to encounter a new person, let alone a zombie. You know, because you have no idea what other people have done to survive and how their mindset has changed because of this and whether they want to rob you or kill you or whatever's happening. And so, seeing people, you know, struggle through this world, you know, was fascinating to me. And as a writer, when I'm like, "Ooh, I don't know what happens next."

• 6:56Speaker 03

  I think, "Well, hopefully there'll be some readers out there, viewers out there that also want to see what happens next."

• 7:03Neil deGrasse Tyson?

  So, what it does is, you are living in extreme conditions when the zombies are coming. And it's not just one thing. It's not just the flood or a crash. These things are out there and they want your brains. So, what does your study of anthropology tell you about how we civilized people behave under those conditions?

• 7:25Speaker 01

  Well, anthropologists would probably tell you different things than some creators of zombie shows. I think what's interesting about-

• 7:33Speaker 02

  Ooh, growing sad on the-

• 7:35Neil deGrasse Tyson?

  No, no, just snap. Wait, wait. But, the success of the show must in part be due to how convincing the portrayals of our behavior are. So, how different can your research be from how much we know we identify with characters that he portrays?

• 7:52Speaker 01

  Interesting question. Um-

• 7:54Neil deGrasse Tyson?

  If his characters were not believable, nobody's gonna watch it and no one's gonna care. So, tell me what your people say.

• 8:00Speaker 01

  I think some people say that, uh-

• 8:02Neil deGrasse Tyson?

  Your people?

• 8:03Speaker 01

  My people.

• 8:03Neil deGrasse Tyson?

  Yes.

• 8:05Speaker 01

  My people say that maybe human beings aren't as inclined to sort of kill one another under, uh, conditions of scarcity as we think they are.

• 8:14Neil deGrasse Tyson?

  Really?

• 8:15Speaker 01

  Yeah.

• 8:15Neil deGrasse Tyson?

  That's very hopeful.

• 8:16Speaker 01

  Yeah, it's hopeful.

• 8:17Neil deGrasse Tyson?

  Yeah, I don't believe any of it, but it's hopeful.

• 8:21Neil deGrasse Tyson?

  I think, especially in America, people, people open up their gun cabinet, you know, the day there is no law and order, then the guns come out, especially here in America, and you wouldn't, and then we'll have this conversation again.

• 8:32Speaker 01

  Yeah. Yeah, it'd be terrible.

• 8:34Neil deGrasse Tyson?

  How do you know who to trust? Uh, and are there any analogues from very early societies that you can draw upon?

• 8:41Speaker 01

  Yeah, exactly. Uh, so this is what anthropologists look at, theorize what early societies might have looked like, and there's a presumption sometimes that if we don't have a strong government, uh, that we're all just gonna eat each other. In, in fact, there are philosophers who have said exactly that. And anthropologists have kind of long argued, we've been sort of an outlier in the social sciences, that have kind of contended that actually, it's, it's only when resources are scarce, or when, uh, people attach value to them, uh, that we start arguing over them. Uh, so, you know, if people, uh, figure out ways to cooperate with one another, uh, then there's no reason for them to kill each other, uh, and there's, they're not naturally inclined to do it.

• 9:23Neil deGrasse Tyson?

  Okay, that's still very hopeful. I mean, I'm, I'm glad some people such as you still exist in the world.

• 9:26Speaker 01

  Yeah.

• 9:27Neil deGrasse Tyson?

  Now, now, it's-

• 9:28Speaker 02

  It wouldn't make for the best show, though, if everyone's just like, "I've got a potato, and I've got a, you know." You can see why they have to be like, everyone would go crazy.

• 9:37Speaker 01

  Yeah, we're kind of the buzzkill, the social sciences.

• 9:40Neil deGrasse Tyson?

  So, is there some sociological, anthropological reason why a zombie is scary to us?

• 9:46Speaker 01

  Uh, yeah.

• 9:48Neil deGrasse Tyson?

  Why do we fear dead things?

• 9:50Speaker 01

  Cause they, uh, uh, look like us, uh, but they're not, um, and-

• 9:54Neil deGrasse Tyson?

  I saw, there was an episode of The Twilight Zone where somebody dies and they put him in a casket, and then there's some twinkle dust on him that no one knows about, and then he just pops up out of the casket, and he's just alive again, and people run out of the church, they, they freak out, and I think, "Wait, he's alive! Love him again."

• 10:11Speaker 02

  They're not happy to-

• 10:12Neil deGrasse Tyson?

  No, no, they don't want, they know, you're dead, they don't want you alive again.

• 10:14Speaker 02

  Yeah.

• 10:15Neil deGrasse Tyson?

  Can you explain this?

• 10:16Speaker 01

  Uh-

• 10:17Neil deGrasse Tyson?

  I know that was a TV show, but still-

• 10:19Speaker 02

  You can't understand it, right? Like, it's like, goes against everything. Like, the one thing we're sure of is that we'll die.

• 10:25Neil deGrasse Tyson?

  Yeah.

• 10:26Speaker 02

  Spoiler alert, I don't know.

• 10:26Neil deGrasse Tyson?

  Right, right, right, right.

• 10:28Speaker 02

  But then, when that, when that happens, and then it stops happening, and you come back to life, that's what terrifies me about zombies. They still look like us, like a terrible version of us.

• 10:38Neil deGrasse Tyson?

  Yeah, yeah.

• 10:38Speaker 02

  That's what's so scary about them to me.

• 10:40Neil deGrasse Tyson?

  So, The Walking Dead is, is post-apocalyptic, right? Zombies have already collapsed society. That's, that's it, okay? And, so, what Kirkman does is try to explore what the struggle is to survive under those conditions. And I asked him about this, let's check it out.

• 11:01Speaker 03

  A lot of what happens in The Walking Dead is the terror I have from the fact that I'm completely dependent on the existence of civilization around me. And that, that really scares me. I could not grow a garden today. You know, I mean, never mind a virus that I can't actually see that could wipe out everyone I know, which is a very real possibility, unfortunately. Like, I couldn't do any little thing to actually survive at this point. I think that we have, we've all made ourselves so weak, so terribly weak.

• 11:37Neil deGrasse Tyson?

  So dependent.

• 11:38Speaker 03

  And dependent, yes. And so, you know, it is, you know, I don't know, like, I like thinking about that kind of stuff, I like analyzing it, and that definitely does go into the, you know, The Walking Dead, and seeing how people can kind of change and adapt. It's like a, it's like a hopeful thing, like, hey, maybe, maybe people can change and adapt if these bad things happen, which I think they can, but I would certainly not be able to.

• 12:02Neil deGrasse Tyson?

  So maybe that's another sort of strong point, that you know implicitly and explicitly that so much of the storytelling that you capture is reflective of how we actually rose up from the caves, to defend each other, to create tribes, to, and what happens if you're out alone? Well, you're at risk, you gotta come back in the wall. There's a lot of sort of anthropology going on there.

• 12:28Speaker 03

  Yeah, I mean, Rick often says, you know, you need people to survive. And I think that's really the story of civilization, people realizing when you work together on bigger and bigger levels, you know, you can accomplish more.

• 12:42Neil deGrasse Tyson?

  So is our dependence on civilization, is that a bad thing?

• 12:47Speaker 01

  Yes and no. Civilization does wonderful things, like it civilizes. But you'll see through, good zombie film has depicted for a good number of years, this sort of loss of creativity. So you take a film like Dawn of the Dead, and it's sort of showing, you know, people shopping, who are kind of, they look like zombies at the windows, and they sort of, the zombies at the windows later look like the people who were shopping. And, you know, people with their cellphones. I like to sit on a park bench sometimes, eat my lunch, and wait to see how long it takes for two people to run into each other. I wish I could have-

• 13:23Neil deGrasse Tyson?

  While they're on their cellphone.

• 13:24Speaker 01

  Yeah, while they're on their cellphone.

• 13:25Speaker 02

  That's funny, because when I was, when he said like, that we get so weak, I was thinking, without my phone, like, when my phone runs out of battery, I just lie down on the ground.

• 13:38Neil deGrasse Tyson?

  It's not even about, can you get food, it's just your phone-

• 13:40Speaker 02

  It's my phone.

• 13:41Neil deGrasse Tyson?

  Your smartphone doesn't work anymore.

• 13:42Speaker 02

  If that's gone, then I'm gone. I lie on the ground, maybe someone could charge it for me, I'll be back.

• 13:46Neil deGrasse Tyson?

  That's great. So, in a way, our smartphone is the epitome of our civilization. It gives us access to our other people, it can tell us where the nearest Starbucks is, we can play games on it. And so, I have to agree, I don't know how, what I would do. I have no idea, I'm too dependent on civilization. You're saying that's not a bad thing?

• 14:06Speaker 01

  Well, I mean, what the concern is, is that these things are turning us into something that's post-human, which is in effect a zombie.

• 14:14Neil deGrasse Tyson?

  What's turning us into post-humans?

• 14:16Speaker 01

  You know, technology, the-

• 14:18Neil deGrasse Tyson?

  Oh yeah, it's a next step, a next point in our evolution.

• 14:22Speaker 01

  Our next, yeah, our evolution is essentially towards post-

• 14:25Neil deGrasse Tyson?

  So the fact that we stare at our devices is a measure of the zombification that has descended upon us?

• 14:34Speaker 01

  Yes.

• 14:35Speaker 02

  And is that why The Walking Dead is so popular now? Because that's like, in the culture, that we're all afraid that we are turning into zombies, so we're like, let's just watch them on TV and forget about what's happening?

• 14:44Speaker 01

  Maybe if we see them on TV, we won't be afraid, that we can sort of say, oh, they're dead.

• 14:51Neil deGrasse Tyson?

  I was in a card shop around February 14th, so Valentine's Day, so one of the cards was, there was no one I would rather sit in bed and look at my cellphone next to than you.

• 15:05Speaker 02

  So romantic.

• 15:07Neil deGrasse Tyson?

  So, one of our men about town, Chuck Nice, he sent us a dispatch because he wanted to find out more about the zombie phenomenon. Let's check him out.

• 15:19Chuck Nice?

  That's right Neil, I'm here in Washington Square Park to talk about the scientific issue that's on everyone's minds: zombies. A zombie apocalypse breaks out right now. How do you survive?

• 15:29Speaker 05

  Baseball bat filled with nails wrapped in chains, and I have a whip.

• 15:35Chuck Nice?

  How would you survive a zombie apocalypse?

• 15:37Speaker 06

  Um, well, I naturally live in Wisconsin, so I don't think, I don't think Wisconsin is a high zombie target.

• 15:43Chuck Nice?

  A zombie apocalypse happens, how would you survive?

• 15:47Speaker 07

  Oh man, I would probably just hide because I wouldn't know what to do.

• 15:50Chuck Nice?

  Oh, you know, that's not a bad, not a bad strategy.

• 15:53Speaker 07

  What would you do?

• 15:54Chuck Nice?

  Um, I would offer my children.

• 15:55Speaker 07

  Okay, wow.

• 15:58Speaker 06

  Yeah, I don't know, I can run pretty fast. I still have some good track speed and they sort of amble along, I think, so, um, I think I could outrun them.

• 16:06Chuck Nice?

  So, yeah, so basically evasion is your strategy.

• 16:08Speaker 06

  Right.

• 16:09Chuck Nice?

  Cool.

• 16:09Speaker 06

  Plus, I'm kinda hairy and balding, so I don't know that I'm as, like, high.

• 16:13Chuck Nice?

  So grossness, grossness. You'd gross them out. Let me give you a little conundrum.

• 16:17Speaker 07

  Okay.

• 16:17Chuck Nice?

  Uh, your significant other, whoever that might be, becomes a zombie. Do you stay with them and love them in their zombieism?

• 16:25Speaker 08

  It honestly depends on the type of zombie, because you have the viral infection ones. So you could keep them until you find a cure, if you're going for that route, but if it's the classic Night of the Living Dead, Race from the Dead mythically, then you just, they're done.

• 16:38Chuck Nice?

  If intelligence makes brains more delicious, how delicious would the brain of Neil deGrasse Tyson be?

• 16:45Speaker 06

  Oh, yeah, he'd probably have a pretty delicious brain, yeah.

• 16:48Chuck Nice?

  Yeah. But you're a zombie chef, how would you cook Neil's brain?

• 16:50Speaker 08

  Probably stir fry.

• 16:53Chuck Nice?

  There you have it, Neil. What have we learned? Your brain is delicious, and I am starving.

• 17:00Neil deGrasse Tyson?

  Chuck Nice, dispatch from Washington Square Park. We're gonna have more on the zombie apocalypse when StarTalk continues.

• 17:20Neil deGrasse Tyson?

  Welcome back to StarTalk. And tonight, we're talking about zombies, the zombie apocalypse, and The Walking Dead. One of the most popular shows ever on cable television. Now, you study how people behave under those situations.

• 17:35Speaker 01

  Yeah.

• 17:36Neil deGrasse Tyson?

  How do you study something that doesn't exist?

• 17:38Speaker 01

  Uh, you would see how they would behave in comparable situations of scarcity or crisis.

• 17:44Neil deGrasse Tyson?

  Okay.

• 17:45Speaker 01

  Sort of speculate how they would behave in those sorts of situations.

• 17:48Neil deGrasse Tyson?

  Okay, so you have enough examples of human conduct in different stressful situations. You bring it together and say, and you suggest plausibly that we would behave in exactly that way.

• 17:59Speaker 01

  Uh, people make certain kinds of inferences, but they might like, uh, look at a disaster situation, you know, following a hurricane, or some other earthquake, or some other natural disaster.

• 18:10Neil deGrasse Tyson?

  So, there's the need to coexist, to support one another?

• 18:14Speaker 01

  Yes.

• 18:15Neil deGrasse Tyson?

  And the risk of that one person will "tribify," I don't know if there's such a word, become a tribe and you're not in the tribe, and we have resources and you don't. None of that is good. None of it. I asked Robert Kirkman about the fears of what you will confront just trying to coexist under those situations and in that stress. Let's check it out. I think another strong point of The Walking Dead is the exploration of individual and group dynamics.

• 18:46Speaker 03

  Yeah. Group dynamics is like a really, you know, fascinating thing, the way that, you know, whether you want to or not, or even without realizing it, you can change your opinion of things just based on the way people are reacting around you, and it's not necessarily a conscious desire to conform, but it's like, uh, it's an evolved behavior in us to keep us from standing out, so that we don't get kicked out of the group and die, right?

• 19:13Neil deGrasse Tyson?

  You don't get culled from the herd, but...

• 19:15Speaker 03

  Right, right, and that's, you know, and that, that, the evolutionary things that remain in us today is just, it's awesome, just, you know, being reminded how much we are really just animals, you know, at the end of the day. But, yeah, I mean, uh... It's heightened a little bit because, you know, there's zombies around and there's danger and, you know, people are willing to do whatever they can to survive, but, you know, it is, you know, there's a lot of group thinking, a lot of things going on that, you know, would change, you know, people's perceptions of things and it's this, you know, the thing that kinda, it goes from the show to the audience.

• 19:52Neil deGrasse Tyson?

  Yes, yes.

• 19:53Speaker 03

  It's cool.

• 19:54Neil deGrasse Tyson?

  Yeah, I feel it. It's real.

• 19:57Neil deGrasse Tyson?

  So Jeff, group think in society, that's gotta be a major topic of study among anthropologists.

• 20:03Speaker 01

  Yeah, so anthropologists would tend to focus on the value that people attach to developing affiliations with one another, so that something like exchange is not grounded in barter, but it's grounded in the importance of establishing relationships with one another. The foundations of economic anthropology, for instance, are in that.

• 20:25Neil deGrasse Tyson?

  But, so let me ask, if group think means we think alike, that's not always good for the group. If the thinking alike is based on a wrong idea.

• 20:36Speaker 01

  Yeah, that would be bad. That would be not good.

• 20:39Neil deGrasse Tyson?

  You agree?

• 20:40Speaker 01

  Yes.

• 20:40Neil deGrasse Tyson?

  Okay, so that would just get rid of the whole tribe. Now, this is a topic that is touched upon in Walking Dead, okay? In it, there's a character called the Governor, okay? And he's just a little suspicious. I mean, initially, you're looking at, I don't, he seems nice and people like him, but something is not right and I can't quite put my finger on it, okay? And so, I think Kirkman has put some deep anthropological analysis into this. So I asked him, where's he balancing the storytelling? Let's check it out.

• 21:16Speaker 03

  And the Governor, you know, was this horrible character who did horrible things, but his daughter had died and he wasn't able to deal with the fact that his daughter had died and became a zombie, so he was like keeping her in his apartment and feeding her and he would like brush her hair and stuff and...

• 21:33Neil deGrasse Tyson?

  In in careful way so he doesn't get bitten.

• 21:35Speaker 03

  Exactly, yeah. And Rick Grimes is the hero, you know, and Rick Grimes has his son Carl. And so I always thought like, the governor really is just Rick Grimes if something bad had happened to Carl at the right time, that would have led him off into this different path. And that was really the kind of the kind of thing that we're doing. One of the coolest things about getting to Walking Dead season six is that if as a viewer, if you've never watched The Walking Dead before, if you sit down and you just watch season six, you're gonna go, this Rick Grimes guy is a lunatic. These people need to watch out. Why are they letting him do these things? This is crazy. This guy's a bad guy.

• 22:13Neil deGrasse Tyson?

  This has been the hero for the first five seasons.

• 22:15Speaker 03

  And he's been the hero for the whole whole show. But if you've been watching from season one, you've been there for every little thing that's happened to change his moral compass to get him to this point. So you're watching season six going, why aren't they listening to him? He knows the truth. Good lord, these people, what are they doing? So it's it's a lot of fun.

• 22:37Neil deGrasse Tyson?

  So tell me about moral compasses in anthropology.

• 22:40Speaker 01

  Well, the examples there really relate to how charisma is established and how you can get, you know, Rick's group and the governor's group to essentially go to war with one another. And there's been a fair number of anthropologists who've studied exactly, tried to study exactly how that emerges, how people relativize certain kinds of morality.

• 23:04Neil deGrasse Tyson?

  Relativize, that's a word?

• 23:06Speaker 01

  Yeah, that's a word.

• 23:06Neil deGrasse Tyson?

  Oh, what does that mean?

• 23:08Speaker 01

  To make relative?

• 23:09Neil deGrasse Tyson?

  Okay.

• 23:12Speaker 02

  Is that is that to do with like, something bad happened to the governor, so that's why he's acting this way?

• 23:16Speaker 01

  Yeah, it's okay to kill him because he's the governor. And that would be, because there's some sort of moral relative.

• 23:23Neil deGrasse Tyson?

  So the moving, the changing platform of circumstances.

• 23:28Neil deGrasse Tyson?

  Gives you, allows you, empowers you to change your moral compass.

• 23:34Speaker 01

  Yeah, exactly.

• 23:35Neil deGrasse Tyson?

  In the face of that new information.

• 23:36Speaker 01

  So, certain rules are established. For example, you're allowed to kill anybody who has actually killed someone else before. Which seems sort of counterintuitive on its face value. I mean, don't you then become the thing that you're then killing? But, these are rules that are established in Kirkman's universe.

• 23:53Neil deGrasse Tyson?

  Okay, so if that changes, where does our morality come from? If it can turn on a dime, based on what happened that you just witnessed, then there is no morality. The morality is just whatever we kind of agree to from one moment to another.

• 24:08Speaker 01

  Well, that's exactly what it is.

• 24:10Neil deGrasse Tyson?

  And morality can become completely perverted, as viewed by us, but be completely normal as viewed by them.

• 24:16Speaker 01

  That's right. Yeah.

• 24:18Neil deGrasse Tyson?

  I didn't want you to agree with that.

• 24:21Neil deGrasse Tyson?

  I wanted you to say, "No, no, Neil, there is a higher morality." And we have found it in my research.

• 24:27Speaker 01

  So, this is the power of a system like civilization? Because it's an agreed upon morality, that, you know, with a certain kind of code. And when it unravels...

• 24:35Neil deGrasse Tyson?

  So, that's what contains it?

• 24:36Speaker 01

  That's what contains it.

• 24:37Neil deGrasse Tyson?

  So, the larger civilization is, the more we can agree on a morality. But, once civilization fragments...

• 24:43Speaker 01

  Yes.

• 24:44Neil deGrasse Tyson?

  Then, moral centers can rise up that are not in agreement with one another.

• 24:49Speaker 01

  Yes.

• 24:50Neil deGrasse Tyson?

  Oh, and those moralities can change from day to day.

• 24:53Speaker 01

  Yep, absolutely.

• 24:55Neil deGrasse Tyson?

  That is spooky.

• 24:56Speaker 01

  That's spooky.

• 24:59Neil deGrasse Tyson?

  I gotta think about that. Alright, we're gonna take a break. More on the analysis of the post-zombie apocalypse, when StarTalk continues.

• 25:14Neil deGrasse Tyson?

  Welcome back to StarTalk, here in the Hall of the Universe of the American Museum of Natural History. And we're talking about zombies, featuring my interview with The Walking Dead creator, Robert Kirkman. Now, I want to know, how did they all become zombies? I asked him. Check it out.

• 25:33Speaker 03

  The Walking Dead, to me, works because zombies are alive is the only buy-in. I think that once you start dealing with and explaining zombies are alive and they're coming to eat you, then you get into the realm of science fiction. It's a spore from space. It's a, it's an alien thing. It's, it's a radiation. It's, you know, then it gets into more of the realms of science fiction and it makes everything less believable. So my whole thing is zombies are here, deal with it.

• 26:01Neil deGrasse Tyson?

  So for your storytelling vocabulary, it's unnecessary to know how and why they became zombies?

• 26:06Speaker 03

  Yes, that drives a lot of people crazy.

• 26:08Neil deGrasse Tyson?

  It's, yeah, it's frustrating, but that kind of keeps the, keeps the interest factor high.

• 26:13Speaker 03

  Yeah, I think so. I mean, to me, it, it, it needs to be very clear from minute one, and I think it has been, that this is not the show about a group of people working to find out what caused the zombies, because that's a very interesting show and could easily be a show. "Oh, we gotta stop this problem. We gotta find this out." Instead, it's a bad thing happened to these people and their lives were ruined and they're dealing with it. And we do try to keep a scientific consistency. It's, it's, you know, we try to make sure that, uh, you know, it's muscle tissue that's actually moving limbs. It's not like these things can magically, you know, operate themselves. And so you do encounter zombies that are so rotted that they can't really move and, you know, it's, it's,

• 26:54Speaker 03

  you know, you, you, if you don't keep things as believable as possible, then things aren't scary. And so, aside from the fact that zombies exist, the bodies operate in a very real way. And, you know, hopefully that makes things all the more terrifying.

• 27:08Neil deGrasse Tyson?

  So he's bringing up human physiology into this equation. And, but if we're gonna talk about the physiology and viruses, we gotta bring in a medical doctor. Not just any medical doctor, okay? I got a medical doctor who is known by his colleagues as Doctor Zombie.

• 27:26Neil deGrasse Tyson?

  It's Dr. Steve Schlozman. Hello, sir. Hello, doctor.

• 27:30Speaker 09

  Thanks very much for having me.

• 27:32Neil deGrasse Tyson?

  So, you wrote a book called The Zombie Autopsies.

• 27:35Speaker 09

  Right.

• 27:35Neil deGrasse Tyson?

  Which intrigues me greatly, because a- as a work of fiction, but you're a medical doctor, you can bring a lot of knowledge into making that an interesting story.

• 27:44Speaker 09

  Yes, so when I wrote The Zombie Autopsies, just to be clear, they're not real, zombies don't exist, but you can't look at a zombie and be a physician and not think to yourself they're sick. So I wanted to try to explain, as best I could, the medical etiology of the zombie process, knowing that zombies aren't real. So I started with the brain, because I'm a brain doctor. Their frontal lobes are gone. They- they can't think in any kind of complicated way. They can't open doors, they can't open windows. You can eat a sandwich while you're running away from a zombie. They are ravenously hungry. That's the ventromedial hypothalamus, that's the region of the brain that's responsible for hunger. Now, there's other issues that I actually find really fascinating, like, how do they

• 28:29Speaker 09

  move if their muscles decane? So you'd have to have a virus that preserves muscle processes, the actin and the myosin, the two proteins that have to run past each other, one for muscles to move. And there are viruses that do that. An easy example, that would be the rabies virus, which still creates clonic movements, where you jerk around a lot, and you have decreased cognition, but you remain mobile. Because a good virus wants you to stay mobile long enough to spread yourself to other people. So I tried to address each of these issues in the book, as I told the story of essentially the impending end of the world.

• 29:03Neil deGrasse Tyson?

  So, in your- now, you work at the Harvard Medical School, is that correct?

• 29:09Speaker 09

  Yeah, I do. I'm at Massachusetts General Hospital, and I teach at Harvard Medical School.

• 29:15Neil deGrasse Tyson?

  So, in your- in your professional opinion, what is the prognosis, the psychiatric prognosis for a zombie? How would you? What? What? I'm just curious. I mean, this is the future, you know?

• 29:30Speaker 09

  Right. So, it's not good. You don't want to get the zombie bug. But, like any disease, it has a natural history. So if you are noticed early in the progression of this disease, so let's say you present to the emergency room with the early stages of what's already recognized as a zombie outbreak, then we have the opportunity to interrupt that outbreak, both in the general population and also in the individual. The longer we let it progress, and more importantly, the more frightened we get, the worse the prognosis becomes for the individual, as well as the society.

• 30:03Neil deGrasse Tyson?

  Okay, so the real bottom line here is, it's whatever attempt we can all invest to preserve civilization, but really, civilization is gone. That's the prognosis here, it seems to me, based on all that I have heard. Dr. Zombie, thanks for being on StarTalk with us. And, yeah, you have a unique expertise here. We might come back to you in case we need it. I don't know what city zombies will attack first, New York or Boston, but we'll call on you first, when that happens, alright?

• 30:34Speaker 09

  I am always on call.

• 30:35Neil deGrasse Tyson?

  Excellent. He's on call, everyone. Alright, thank you, Dr. Z. Thank you.

• 30:39Speaker 09

  It's been my pleasure. Thanks for having me.

• 30:43Neil deGrasse Tyson?

  So, when we come back to StarTalk, we're gonna get hard data on the zombie apocalypse, when we return.

• 31:01Neil deGrasse Tyson?

  Welcome back to StarTalk, from the American Museum of Natural History, right here in New York City. We've been talking about the zombie apocalypse, and the sociology, the anthropology, the biology of zombies. I'm an astrophysicist, you're a comedian, we got the anthropology side of it, but I need some data. I need some numbers. And anytime I feel the need, we need some ammonia. Mona, can I get some data, please?

• 31:29Neil deGrasse Tyson?

  Everybody, this is Mona Chalabi, and she's a data journalist, and she's here to enlighten us on zombies by the numbers. So Mona, yes, what do you have for us?

• 31:39Speaker 10

  So it's not exactly data, it's a formula that I have for you. And it's a formula that comes from a mathematician called Robert Smith. And this is his formula that you need to know if you want to understand zombies. It is B N in parentheses, S over N in parentheses, multiplied by Z equals B S Z.

• 31:56Neil deGrasse Tyson?

  Okay.

• 31:57Speaker 10

  So the B is the risk of transmission, the N is the total population, S is the number of people who are susceptible, so I assume that's basically humans, that's us, and the Z is the zombies. And basically, the outcome of that formula is that humans and zombies cannot peacefully coexist. There's no such thing as a stable equilibrium, because zombie population growth happens so quickly that in an us-versus-them scenario, they're gonna win.

• 32:22Neil deGrasse Tyson?

  So is this like a predator-prey scenario?

• 32:24Speaker 10

  Exactly.

• 32:25Neil deGrasse Tyson?

  Where one rises, the other falls, and they don't coexist peacefully, somebody's always eating somebody else?

• 32:30Speaker 10

  Exactly. And the number-one question for that is, how many predators are there? So now, we want to try and quantify how many zombies there would be if this were to actually happen. And to do that, you need to understand how many people have ever been born on planet Earth. I'm guessing you probably already know this number.

• 32:45Neil deGrasse Tyson?

  I totally know that. I mean, this is, we just noticed. Actually, there's some uncertainty, but isn't it like between 70 and 100 billion people?

• 32:52Speaker 10

  I would put it at the upper end of that. And the reason for that is...

• 32:55Neil deGrasse Tyson?

  Closer to 100?

• 32:56Speaker 10

  Yeah. And it comes from a demographer at the Population Reference Bureau, and what he did was he took as his starting point 50,000 B.C., and that's when the UN thinks that the first about, like, the Homo sapiens first appeared. And obviously, you're gonna take that all the way up to present. And they estimate that population growth was pretty much steady until 1850, when wars and famine started to happen. And it's quite possible that there were wars and famines before 1850, we just don't have good statistics from the Middle Ages.

• 33:23Neil deGrasse Tyson?

  Okay, right.

• 33:23Speaker 10

  And then going on from that, we have about 108 billion people who have ever been born. But obviously, we want to subtract from that everyone who is alive today, which I'm sure you know this number, Neil.

• 33:34Neil deGrasse Tyson?

  Yeah, seven, seven plus billion.

• 33:35Speaker 10

  Exactly. So what we're left with is the kind of overall ratio of the dead to the living, which is about 14 to 1, which is kind of crazily low, that there's only 14 people dead for every single one of us.

• 33:46Speaker 02

  I would get like 20,000 dead people.

• 33:48Neil deGrasse Tyson?

  Yeah, so that is an interesting, interesting fact. So I once tweeted about this, using some of these numbers, I said, if, if, if everyone who has ever died is a ghost, then there's like 14 ghosts per person, that would just be annoying. It's like, get out of here.

• 34:06Speaker 10

  I think what's kind of more interesting is how Americans think they would fare in an apocalyptic scenario. And again, we have data, right? Last year, YouGov asked 1,000 respondents how they think they'd do if there was an apocalypse. And Americans are kind of confident about this. So only 11% think that they'd die early on, 42% think they'd do as well as everyone else, and a third think that they'd outlast other people.

• 34:29Neil deGrasse Tyson?

  Yeah, that's because they all have guns. This is pretty, in America, yeah, I get it.

• 34:34Speaker 10

  The CDC, however, disagrees. So the CDC spoke-

• 34:37Neil deGrasse Tyson?

  The Center for Disease Control.

• 34:39Speaker 10

  That's exactly the one. At the Center for Disease Control and Prevention, one of their spokespeople said, "The CDC does not know of a virus or condition that could reanimate the dead or could produce zombie-like symptoms." That's their final word on things.

• 34:54Neil deGrasse Tyson?

  Okay. So Mona, thank you for sharing your data with us. Yes, the Center for Disease Control, they're the ones who have something to do with protecting us or alerting us if there's a problem. And I asked The Walking Dead creator, Robert Kirkman, about a zombie outbreak in America and what role the Center for Disease Control might play in this. Let's check it out.

• 35:21Speaker 03

  The CDC actually, you know, they issued a zombie preparedness guide.

• 35:26Neil deGrasse Tyson?

  What?

• 35:27Speaker 03

  That, uh, yeah, because the things that you need to prepare for a zombie apocalypse are also the things you need to prepare for hurricane and earthquakes.

• 35:36Neil deGrasse Tyson?

  Or an asteroid.

• 35:36Speaker 03

  Tornadoes. Well, asteroids, there's nothing you can do to prepare for an asteroid, right? I mean...

• 35:42Neil deGrasse Tyson?

  Well, the aftermath of the asteroid, right, right?

• 35:44Speaker 03

  I would just eat a bunch of cheeseburgers, because I'd be like, "It's over, I can eat as many cheeseburgers as I want." Uh, but the CDC, uh, put this guide out that, I think, crashed their website, like, people, you know, were clamoring to get this stuff, and, and if any part of what The Walking Dead has to do with this zombie phenomenon leads to people being more prepared for natural disasters because the CDC is tricking them into reading this cool thing about the zombie apocalypse, like, I think that's the, literally, that it might be the best thing that's come out of The Walking Dead.

• 36:17Neil deGrasse Tyson?

  So, so he's got the CDC paying attention to what he's doing. Now, we, we actually have possession of this, of this booklet, and it's, it's, it's amazing, just check it out. So, there it is, and I, I am in physical possession of this booklet.

• 36:32Speaker 02

  That's what the American people's tax dollars have paid for.

• 36:35Neil deGrasse Tyson?

  Yes!

• 36:38Neil deGrasse Tyson?

  Because we know what's important here, this is America, we do important stuff.

• 36:42Speaker 02

  But it's like about how to survive a hurricane and stuff too, right? It's like, get your matches.

• 36:46Neil deGrasse Tyson?

  Yeah.

• 36:47Speaker 02

  Collect your pets.

• 36:48Neil deGrasse Tyson?

  Yeah. So, there you have it, an official guide for surviving the zombie apocalypse, brought to you by America.

• 36:58Neil deGrasse Tyson?

  So, I thought you were terrified of zombies.

• 37:00Speaker 02

  No, I hate them, and I'm scared of them.

• 37:02Neil deGrasse Tyson?

  Okay, so how about right here, we got...

• 37:06Speaker 02

  Yes!

• 37:09Speaker 02

  Oh my god.

• 37:12Neil deGrasse Tyson?

  Wait, no, wait, wait, wait!

• 37:22Neil deGrasse Tyson?

  Where does she come from?

• 37:23Speaker 02

  Is that your intern?

• 37:28Neil deGrasse Tyson?

  Is that what happens to your interns? If you work here too long, that's what it'll do.

• 37:33Speaker 02

  That's awesome.

• 37:34Neil deGrasse Tyson?

  Are these real? This is...

• 37:39Speaker 02

  My heart is actually racing.

• 37:42Neil deGrasse Tyson?

  So, coming up, we'll answer your questions about the science of the zombie apocalypse. When StarTalk achieves...

• 38:04Neil deGrasse Tyson?

  We're back on StarTalk. And for this segment, we have the ever-famous Cosmic Queries edition.

• 38:11Speaker 02

  Are you ready?

• 38:11Neil deGrasse Tyson?

  Yes. Maeve, you're gonna read questions that are drawn from our fanbase?

• 38:16Speaker 02

  Yep.

• 38:17Neil deGrasse Tyson?

  And these are all about the zombie apocalypse directed to me, but I don't claim... I gotta bring in some anthropological insight if we need it.

• 38:25Speaker 02

  You're allowed to ask a friend.

• 38:26Neil deGrasse Tyson?

  I'm allowed to ask a lifeline here. Okay, bring it on. Okay, ready, go.

• 38:31Speaker 02

  James Coulter from Arkansas, "If zombies can't die, could we pop them in a giant hamster wheel for energy?"

• 38:37Neil deGrasse Tyson?

  That is brilliant. That... brilliant. Yes. Okay, if you gotta live with zombies, let's put 'em to work. What you do is you dangle some brains in front of them, and they just keep walking. And they're like on a stick that sticks in front of them.

• 38:52Speaker 02

  Yeah.

• 38:52Neil deGrasse Tyson?

  And they're too stupid to know that it's dangling. Don't be sad for zombies.

• 38:56Speaker 02

  Sorry, no, I know.

• 38:57Neil deGrasse Tyson?

  Don't be like feeling for them. They're zombies. Yes, I would so do that. Go, next.

• 39:01Speaker 02

  Mike H. from St. Louis, "Would an undead zombie violate the laws of thermodynamics by reversing the irreversible processes we call death?"

• 39:10Neil deGrasse Tyson?

  So, death is only irreversible because we do not know how to reverse it. Alright, I don't make any proclamations like that. So I'm not even having that conversation, but let's talk about the physics, okay? The physics reason why zombies don't work, okay?

• 39:24Speaker 02

  Yeah.

• 39:25Neil deGrasse Tyson?

  They are moving, they must have a metabolism.

• 39:28Speaker 02

  Yeah.

• 39:29Neil deGrasse Tyson?

  If they do not get human brains, their energy source, whatever it is, is gonna run out and they will die.

• 39:36Speaker 02

  Mm-hmm.

• 39:37Neil deGrasse Tyson?

  That's how that, that's how that goes.

• 39:39Speaker 02

  Okay.

• 39:39Neil deGrasse Tyson?

  Okay, good.

• 39:40Speaker 02

  Uh, Tom Ricks from Perth in Western Australia. Are you more scared of zombies, climate change, or an unseen asteroid collision with Earth?

• 39:48Neil deGrasse Tyson?

  Ooh, okay, I have equal fear of all three.

• 39:51Speaker 02

  Really?

• 39:53Neil deGrasse Tyson?

  I share all three fears as a second place fear to my number one fear.

• 39:59Speaker 02

  Mice.

• 40:00Neil deGrasse Tyson?

  Mice, no, no, no, no. No.

• 40:03Speaker 02

  Oh, no, sorry, I was thinking of somebody else.

• 40:05Neil deGrasse Tyson?

  Yes, so my number one fear is the consequences of leaders of the world who are not scientifically literate.

• 40:17Neil deGrasse Tyson?

  That is my biggest fear. Because if you're scientifically illiterate, all of the rest of that will happen.

• 40:22Speaker 02

  Yeah.

• 40:23Neil deGrasse Tyson?

  But if you're literate, you'll, you'll take precautions and you'll understand and you will put in the kind of legislation and changes necessary to protect the future of the human species, because that's what science has been doing ever since it was invented. Nick, wait, let me hear that.

• 40:39Neil deGrasse Tyson?

  Let me hear, okay, love that, okay. Okay, you got one more? Okay.

• 40:43Speaker 02

  Okay, um, since, this is from Jesse Anderson in Seattle. Since the living pump tons of CO2 into Earth's atmosphere and zombies don't, is this Earth's way of staying healthy?

• 40:55Neil deGrasse Tyson?

  So to make us extinct and put the zombies in place, uh, is that part of the Gaia hypothesis where Earth is, wants to take care of itself and keep its own equilibrium no matter what else is happening? If it has to render us extinct by creating zombies, then why not? What we don't know is what the zombies will do with the Earth once they eat all of our brains. That, I don't know that that has been researched. So I will not assert that a world with zombies not spewing CO2 is better than a world with humans who are.

• 41:30Speaker 02

  Okay, great.

• 41:32Neil deGrasse Tyson?

  So, coming up, Bill Nye the Science Guy, good friend of mine, as you know, is gonna explain why science will save us from the zombie apocalypse when StarTalk continues.

• 41:55Neil deGrasse Tyson?

  Welcome back to StarTalk at the Rose Center for Earth and Space. We've been talking about the science of zombies and the zombie apocalypse, and we've been featuring my interview with Robert Kirkman, the creator of Walking Dead. There's nothing like it, just nothing like it. And I talked to him about science characters that he has in his show. Let's check it out. You've got a scientist character, Eugene Porter. There's no prerequisite to having a science character on a show, such as one about zombies, so where did that come from?

• 42:33Speaker 03

  Well, I mean, I don't know, I just, I needed somebody who could accomplish things. I mean, you know, I'm sorry.

• 42:40Neil deGrasse Tyson?

  And not just wield weapons and cut heads off?

• 42:43Speaker 03

  Well, you know, when we get into season six, you'll see that, you know, and it kind of starts in season five, and it's been going on for a while in the comics, but they have some semblance of civilization. The story has gone on long enough that these people are getting to a point where they have a safe zone that is established, and the world's still very dangerous, but, you know, in the comic now, they're building windmills and they're milling bread, and, you know, having a scientific character there, we always borrow from the knowledge that came before, right? So, and adding to it. So if civilization were to fall, someone with, you know, limited scientific knowledge like Eugene Porter, who's not the greatest scientist in the world, but, you know, he's got some scientific knowledge,

• 43:28Speaker 03

  could utilize all of that stuff that's been established to very easily get us back to civilization.

• 43:36Neil deGrasse Tyson?

  So, who are the most useful people to have around?

• 43:39Speaker 02

  Comedian.

• 43:40Neil deGrasse Tyson?

  Comedian.

• 43:42Speaker 02

  I mean, I know that we're not needed in an emergency. You know, there's that, like, expression, laughter is the best medicine.

• 43:49Neil deGrasse Tyson?

  Yeah, okay.

• 43:49Speaker 02

  But probably, like, medicine is the best medicine.

• 43:51Neil deGrasse Tyson?

  I'm thinking, yeah, I would kind of agree with that.

• 43:55Speaker 02

  So I'd probably be the first to go. I don't know, I guess you, would you say anthropologists are useful in a...

• 44:00Speaker 01

  No, no, I mean, we're a step above, like, actuaries, but...

• 44:06Neil deGrasse Tyson?

  But, but, so you've studied cultures and civilizations. So if you were to make an ark of people to survive whatever happened, but the ark would move on, what mixture of professions would you put in it?

• 44:19Speaker 01

  I, I think you would need people who were capable of servicing basic needs for the rebuilding of society.

• 44:26Neil deGrasse Tyson?

  Okay, does that include leaders who have no such talents?

• 44:29Speaker 01

  Leaders don't have any talents, they...

• 44:32Neil deGrasse Tyson?

  No, no, they do, they bring people together. I'm amazed that leaders exist at all, and not everyone can be a leader. Some people are like not leaders, right? And so, you go to a leader, and a leader can compel communities to stick together, to bind, and so, even though they can't build a windmill.

• 44:52Speaker 01

  Yeah, I, well, I guess you might need a psychologist, a social psychologist, who could identify who a non-tyrannical leader might be. Someone that's not like the governor.

• 45:04Neil deGrasse Tyson?

  Oh, there you go, so that's why we need you. To help us know who would not be a totally messed up leader.

• 45:09Speaker 01

  Yeah.

• 45:10Neil deGrasse Tyson?

  See, I found a way to keep you.

• 45:13Speaker 02

  And they're like symbols, but actually useful people would probably be like a farmer, right? Or an engineer.

• 45:18Neil deGrasse Tyson?

  Yeah, yeah, no, we agree. And we need the comedian at night, just so we can laugh at ourselves. Yes. So Maeve, you're in the ark, I promise.

• 45:26Speaker 02

  Thank you.

• 45:27Neil deGrasse Tyson?

  Now, as you know, every one of these shows, Bill and I, we catch up with him. He has a dispatch from somewhere in the city, and this one is on how science will protect us from zombies. Check it out.

• 45:40Bill Nye?

  This is the ruins of the old smallpox hospital. It's isolated on an island, right in the middle of New York City. It's where smallpox victims used to come to try to recover, or die. It's a horrible disease. Your skin gets covered with fluid-filled pox. It scars you for life, if you survive. Now, by all accounts, smallpox victims were low-energy, lethargic, exhausted, zombie-like. And this may have led to certain cultures believing that you could bring people back from the dead, or the nearly-dead. They tried all sorts of things: incantations and witchcraft. It may have led to the belief in zombies.

• 46:23Bill Nye?

  But for my part, I've never seen any evidence of zombies or witches. Except for this one woman I used to know. But that aside, smallpox is serious business. Three hundred million people around the world died from it. And it was Benjamin Jethsy who realized that milkmaids, women who milked cows who had contracted the non-lethal cowpox, never got infected with smallpox. Which led to Edward Jenner inventing the world's first vaccine. And that word, by the way, comes from the word for cow. Now if there ever is anything as scary or deadly as smallpox...

• 47:02Bill Nye?

  Or... The zombie apocalypse.

• 47:08Bill Nye?

  Science will save us.

• 47:15Neil deGrasse Tyson?

  Alright, Bill Nye!

• 47:21Neil deGrasse Tyson?

  When I think of zombies as this pop culture phenomenon, I recognize that sometimes studying one thing gives you deep insight into something else. And so when I think of zombies, I think of them as an analog, as others have, to disasters that could otherwise befall us. And one of the powers of science and mathematics is certain problems that don't even have to be real. If you can represent them mathematically, and if there are science analogues to it, then the fact that everybody is interested in this... Even when it's not real can give you insight into solutions for that. And the zombie phenomenon has done just that.

• 48:05Neil deGrasse Tyson?

  How quickly do they, does it spread? At what rate? Who does it affect? And why? And how? Some of the greatest discoveries in the history of the world have come about simply because somebody had a little side interest and we saw the new math and the new science that arose from it. And it transforms civilization. And these are the lessons from StarTalk this evening. This has been StarTalk from the American Museum of Natural History. I'm Neil deGrasse Tyson, your personal anthropologist. And as always, I bid you to keep looking up.