What Happens Inside Earth's Forbidden Zones?

What grows in the spaces humans are forced to abandon? Hannah brings Michael an actual piece of barbed wire from the Korean Demilitarised Zone, one of the most heavily fortified and forbidden borders on Earth, and it sends them somewhere unexpected. From deserted no man's land and radioactive exclusion zones to remote islands that most of humankind has quietly agreed to leave well alone, they explore the surprising ways life adapts to the damage we leave behind. Plus your questions: the scientific fact that scared Michael most, where tectonic plates actually go when they collide, and a very good would you rather. Send questions of your own to [email protected] or find us at r/TheRestIsScience. ------------------- For more information about Cancer Research UK, their research, breakthroughs and how you can support them, visit ⁠⁠https://cancerresearchuk.org/restisscience⁠⁠ Cancer Research UK is a registered charity in England and Wales (1089464), Scotland (SC041666), the Isle of Man (1103) and Jersey (247). A company limited by guarantee. Registered company in England and Wales (4325234) and the Isle of Man (5713F). Registered address: 2 Redman Place, London, E20 1JQ. ------------------- Find The Rest Is Science all over the internet by ⁠⁠clicking here.⁠⁠ ------------------- Video Producer: Adam Thornton + Oli Oakley + Jack MeekAnimator: Sam BensonVideo & Social: Bex TyrrellAssistant Producer: Lucy LipscombeProducer: Simona RataSenior Producer: Lauren Armstrong-CarterChief Digital Officer: Samuel OakleyExec Producer: Neil Fearn Learn more about your ad choices. Visit podcastchoices.com/adchoices

• 0:01Speaker 00

  Welcome to Rest Is Science. I'm Hannah Fry.

• 0:03Speaker 01

  And I'm Michael Stevens.

• 0:04Speaker 00

  And I've got a little treat for you today because we've got a field notes episode, as usual, this part of the week. A little bit later on, we're going to come to your questions, your, your, your big ideas, your, your interjections that you wanted to send us at [email protected]. But right now I've got, I've got a little object for you, Michael.

• 0:22Speaker 01

  I love the field notes where you bring the object because I get to just be an audience member for a while, you know?

• 0:28Speaker 00

  You genuinely don't know what's coming up.

• 0:30Speaker 01

  I thrive when I don't know what's going on.

• 0:33Speaker 00

  Okay. Shall I give you an audio clue first?

• 0:35Speaker 01

  Yes, please do.

• 0:36Speaker 00

  I'll be honest with you, if you get this from the audio clue, I think there's a 0% chance. I think there's a 0% chance that you're going to get this from the audio clue.

• 0:45Speaker 01

  Okay. Now you've got me really, really interested. I'm going to see if I can crack this with just the audio.

• 0:50Speaker 00

  Okay, ready?

• 0:53Speaker 01

  It sounds like a, like a baby's rattle type toy, like keys on a plastic keychain. I want to say a plasticky sound. It wasn't like metal, unless it was hollow metal.

• 1:04Speaker 00

  I think it's more like metal on glass.

• 1:07Speaker 01

  Well, you know what it is though. What the heck?

• 1:09Speaker 00

  Sorry.

• 1:10Speaker 01

  It's like a, it's like a, something rolling around in a, in something hollow, like a, a ball in a ball.

• 1:17Speaker 00

  You're, okay, look, obviously that's the absolute closest you're going to get. Cause what it actually is, is a bit of barbed wire in a glass jar.

• 1:26Speaker 01

  Oh.

• 1:27Speaker 00

  Why do I have a bit of barbed wire in a glass jar?

• 1:29Speaker 01

  I don't know. It looks strange.

• 1:31Speaker 00

  Hmm. Doesn't it? Looks very strange indeed. This is a bit of barbed wire from the Demilitarised zone between North and South Korea.

• 1:41Speaker 01

  If you're only listening, Hannah is holding a glass jar that's kind of a little taller than a film canister, but about as wide, if you're old enough to remember what those are. And it's got like a cork at the top, but inside there's a little snipping, a little piece of, of barbed wire and like some rocks.

• 1:56Speaker 00

  There is a gift shop at the DMZ.

• 1:59Speaker 01

  I didn't know that.

• 2:01Speaker 00

  Is that not the craziest thing you've ever, and I'm not talking about like, oh, you're away from the demilitarized zone. No, no, no, no, no. I mean, literally in the demilitarized zone, there is a fun fair.

• 2:12Speaker 01

  Oh, that makes so much sense though, because so many tourists to South Korea would be like, I want to go up there and see, see North Korea with my eyes and I've got money to spend.

• 2:25Speaker 00

  Uh huh.

• 2:25Speaker 01

  I bet they're just putting up new barbed wire every day and then clipping it up.

• 2:29Speaker 00

  Just to take that old stuff down.

• 2:38Speaker 00

  This episode is brought to you by Cancer Research UK.

• 2:41Speaker 01

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• 4:18Speaker 03

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• 4:51Speaker 00

  The other things that you could buy, by the way, at the DMZ, I sort of feel a bit funny playing Z, but it also doesn't sound right to say DMZ. The, the other things that you could buy at the DMZ gift shop are wallets that are shaped like hand grenades.

• 5:06Speaker 00

  And then all kinds of like little figurines of North Korean leaders that I think possibly the North Korean leaders would not enjoy.

• 5:17Speaker 01

  But you know, the people who own those gift shops, they're lobbying both countries very hard to keep this Demilitarised zone going because their business depends upon the political situation.

• 5:29Speaker 00

  You're absolutely right. And they're not the only ones who are desperate to keep this walk going. Because actually what I want to talk to you about today is not the gift shop at the DMZ. It is the animals that have flourished.

• 5:46Speaker 01

  Oh yeah.

• 5:48Speaker 00

  In the no-go zone that has been created by human intervention. And there's a few of these places around the world, right? The DMZ is one of them, which has basically been completely unoccupied by humans since the 1950s. And in the decades that have passed since, there is this complete flourishing of nature within that zone in this crazy way. So nobody can step foot in this zone.

• 6:16Speaker 01

  Yeah.

• 6:17Speaker 00

  Certainly not, you certainly wouldn't be authorized to do so.

• 6:19Speaker 01

  Right. I mean, you, you can, but you may not.

• 6:22Speaker 00

  You may not. You may not. And also it would be extremely ill-advised because the entire place is totally covered in landmines.

• 6:29Speaker 01

  Yeah.

• 6:29Speaker 00

  So also you would not and should not.

• 6:32Speaker 01

  Okay, good. You may not, you should not, and you could not. You, well, pieces of you might make it over.

• 6:40Speaker 00

  So even conservationists are not able to go into this zone in order to do proper surveys of the animals that are there.

• 6:49Speaker 01

  So then what flourishes?

• 6:51Speaker 00

  So there's all kinds of bird species. There are, there are rumors that there are leopards and tigers that have found a home within this region. No tiger, there's no sort of really good evidence of any tiger having been spotted. So I think that one might be a myth. But there are boars, there are deer, there are vampire deer, in fact, which, which don't grow horns, they grow sort of like funny teeth.

• 7:20Speaker 01

  Oh, wow.

• 7:21Speaker 00

  But the other thing is all of these paddy fields that were abandoned.

• 7:24Speaker 01

  Wait, paddy fields? Like, I know how, about how long the, the, the demilitarized zone is, but how thick is it? How wide across?

• 7:33Speaker 00

  Only about four kilometers.

• 7:35Speaker 01

  Okay. So you've got a four kilometer band separating North and South Korea, where people may, should and could not enter. Nature is healing there in its own way.

• 7:46Speaker 00

  And it's healing really well, by the way. There's, there's some estimates that say 38% of the critically endangered species in Korea live in that tiny little area.

• 7:58Speaker 01

  Whoa.

• 7:59Speaker 00

  So it's not just the gift shop owners who are desperate for this place, not for the war to never end. You know, if, if suddenly there was a peace treaty and everybody, there's reunited Korea or however it ended up being sold, it would just be devastating for, for their ecosystem that has been created in this, in this abandoned land, right? It would be completely devastating. The paddy fields, by the way, that were abandoned in the 1950s, they turned over very quickly into grassland. And then they very quickly from then started growing willow. And now all of these paddy fields have turned into these elder dominated

• 8:42Speaker 00

  forests. So you get these little pockets. And it's just this amazing study that you can make in what happens when humans completely vacate an area. It's like really extraordinary just how much nature thrives.

• 8:55Speaker 01

  And it's different than what's going on in Chernobyl because there you have the added variable of radiation.

• 9:03Speaker 00

  Exactly. We've talked about the black frogs that you see in Chernobyl, how the radiation has ended up impacting the evolutionary path of, of different creatures that are there, that frogs with darker skin were able to survive the, the radiation better than those that didn't. Those that didn't would die out. And, and so the closer you get to the original site in Chernobyl, the darker the frogs get. There are places that are sort of in the middle. So I was incredibly lucky to get to go to the DMZ when I was filming a documentary. I've also been inside the exclusion zone of Fukushima, which is somewhere between the two. So it has the radiation element that Chernobyl has, but nowhere near the same sort of scale, right? And it's, Chernobyl is like, there's certain

• 9:48Speaker 00

  parts of Chernobyl that will never be inhabitable by humans, right? There's no, there's no going there ever. But in Fukushima, the idea is that slowly, slowly they are trying to decrease the radius of, of how far, of how far people are not allowed in. So it's sort of like a, it's, it's not never, but how did we say it for, for the DMZ? You can't, you shouldn't, you won't, or something.

• 10:16Speaker 01

  You, yeah, you may not, you should not, and you cannot.

• 10:20Speaker 00

  Right. So from Fukushima, it's more like, you may not, you probably should not, and you can maybe in future, essentially.

• 10:29Speaker 01

  Oh, it's a little more hopeful.

• 10:30Speaker 00

  A little more hopeful.

• 10:31Speaker 01

  Tell me about Fukushima.

• 10:33Speaker 00

  All right. So here's the thing. Okay. Going inside Fukushima is...

• 10:39Speaker 00

  It's wild. It's really wild.

• 10:42Speaker 01

  So describe it for me because I've never been there. It is an area of land.

• 10:47Speaker 00

  So you are just inside of the coast in Japan where the tsunami basically overwhelmed the sea wall of a power plant.

• 10:57Speaker 01

  A nuclear power plant.

• 10:58Speaker 00

  A nuclear power plant, important, important distinction, flooded the reactor and caused radiation to spill out essentially in the surrounding area. So it remains very radioactive, nowhere near as bad as Chernobyl, but really dangerous still. And when you go in there, so we didn't get to go right up to the reactor, but we got to go in the sort of the controlled zone. And when you go in, there are human settlements within that region that were abandoned on the day and have never been returned to. Not only has the forest and, you know, nature essentially reclaimed these buildings, it sort of swallowed them up from the ground and around. The roof is caving in, there's rubble everywhere, just the elements have

• 11:43Speaker 00

  had their way essentially with these buildings. But you also, where they are closed off and locked away, you look inside the windows and you get this sense of the panic people felt when they left on that day.

• 11:57Speaker 01

  And for context, this was 15 years ago.

• 12:00Speaker 00

  It was 15 years ago. Right, exactly.

• 12:01Speaker 01

  So that's how long humans have left it abandoned to nature.

• 12:06Speaker 00

  Or the other way around is to say that's how quickly it gets swallowed by nature, how quickly nature returns to dominance. You look in the window and you see the slippers of people sort of rushed as they were leaving and they were putting their shoes back on to get out of the building. There's like teddy bears kind of strewn on the side. There's like, there was one place where I looked in the window and there was like a crate of half-empty beers that they must have been aiming to take to the recycling, but then never had the opportunity to do so. And when we got to go inside this exclusion zone, we were going for this story about rewilding and we spoke to some researchers and they told us that there were some radioactive bears within the exclusion zone. We were going

• 12:50Speaker 00

  to go and film these radioactive bears. And then when we got there, we realized there'd been a slight mistranslation because it wasn't, it wasn't radioactive bears, it was boars.

• 12:59Speaker 01

  Oh, okay. Still fun.

• 13:02Speaker 00

  Still fun. But also, it wasn't boars so much as boar singular. And actually, it had only ever been caught on camera once. So instead, we filmed some radioactive dragonflies, which was, you know, a close second.

• 13:17Speaker 01

  So they're radioactive in that they are themselves radioactive. If they land on you, you're exposed to ionizing radiation from the body of the dragonfly.

• 13:28Speaker 00

  I don't think within Fukushima, it's quite that extreme.

• 13:31Speaker 01

  Okay, so it's more like dragonflies that live in an exclusion zone.

• 13:37Speaker 00

  Exactly right. But why I sort of started thinking was how many of these different exclusion zones there are around the world? How many different places are now completely untouchable because of human, human decisions, human moments? So you've got Chernobyl, of course, Fukushima. There's also a place called Lake Karache in Russia. And this is a place that the lake shore, sort of this, you know, around this little lake, it read around 600 rontgen in 1990, which is basically you stay there for an hour and you're dead. Okay, that's kind of the level that we're talking.

• 14:18Speaker 01

  That's a lot.

• 14:19Speaker 00

  This is where the Russians were testing their nuclear, nuclear weapons essentially. There's also the Bikini Atoll Marshall Islands, where 23 different bombs between 1946 and 1958 were detonated. It's still totally uninhabitable. And the problem there, it's not so much the ground, it's more about the food chain, because all in the coconut palms and the breadfruit, anything that's grown there will also carry a dose. So when you were saying about radioactive dragonflies, it's radioactive coconuts.

• 14:52Speaker 01

  Yes, and the people who used to live there still don't.

• 14:56Speaker 00

  Still don't, right? I mean, astonishing.

• 15:00Speaker 01

  I mean, at the time, the US government really did think it was going to be temporary. They were like, oh yeah, you guys got to leave for a bit, we'll do our tests and you can come back. And now I think a lot of them are, and their descendants are in like Arkansas.

• 15:14Speaker 00

  Right. And, and the thing is, I mean, there's, some of these places may eventually be re-inhabitable. So, you know, Bikini Atoll, for instance, that researchers can go there. It's, it's not that you, this sort of like passing dose isn't, if you're very careful and very, you know, take the correct precautions, that it is possible to visit. But there are other places in Marshall Islands, the tomb, for example, where there is a concrete dome of 120,000 tonnes of plutonium contaminated debris. And also, it's sort of cracking, which is absolutely bad.

• 15:50Speaker 01

  Oh, no.

• 15:51Speaker 00

  Bad. But that place is indefinitely. There's no going there ever. You know, it's just too much.

• 15:56Speaker 01

  And where is that?

• 15:57Speaker 00

  That's also Marshall Islands as well. Runeet Island is called.

• 16:00Speaker 01

  And it's called the tomb. Oh, the, what's the island called?

• 16:04Speaker 00

  Runeet Island.

• 16:05Speaker 01

  Runeet Island.

• 16:06Speaker 00

  Hmm. There are other places that are not just because of nuclear testing. So there is in Zone Rouge, it's called in France, which is, it's still legally sealed after World War I. This is a place near Verdun. And 99% of the plants that grow there will die due to arsenic in the soil. I mean, we're talking cra, it's about 17% by weight in the soil, right? This is like, it's horrendous.

• 16:37Speaker 01

  So human wandering around is excluded for good reason. Have they tried to do anything to fix this? Or are they just kind of leaving it?

• 16:48Speaker 00

  Just leaving it, I think.

• 16:49Speaker 01

  Yeah.

• 16:50Speaker 00

  Someone in the comments may correct me, but, but my understanding is they're leaving it. In 1919, they were like, it's impossible to clean, human life's impossible there, don't even go there.

• 16:59Speaker 01

  That was used in World War I, and now it's just polluted this area of land so much that even the plants aren't, they're not flourishing there.

• 17:08Speaker 00

  No, exactly.

• 17:09Speaker 01

  Maybe for their short lifetimes they are, because there's no human development happening.

• 17:14Speaker 00

  And that's one of the things that makes the DMZ so interesting, because, I mean, they did spray with Agent Orange when the line was drawn on the map, essentially when this, this separation of North and South happened, which was when Japan evacuated Korea during the Second World War. And there were a couple of American generals who'd never been to Korea and needed to work out which bit the Soviets should take and which bits the Americans should take. And they just chose a line of latitude on the map, didn't take into account that there were railway lines going through there, there were rivers cutting across. It's just like, just kind of very bluntly and brutally. There was a

• 17:53Speaker 00

  bit of fighting for a few years instantly until 1953, when they signed this peace treaty. Sorry, forgive me, it's not a peace treaty. Crucially, it's a ceasefire. So actually, they are still technically at war. But that was what really set the boundaries of these two. But that's sort of what makes it interesting is that it is a byproduct of war, but there aren't these things like anthrax, radiation, you know, all of these incredibly horrible arsenic or anything like that. There's none of these sort of incredible weapons of war that make it mean that their wildlife can't flourish.

• 18:31Speaker 01

  It's not polluted with a substance. There are landmines there. Those wouldn't affect a dragonfly or a plant, but a tiger?

• 18:39Speaker 00

  A tiger, maybe.

• 18:43Speaker 01

  Maybe, but we're not sure if there are tigers there or not.

• 18:46Speaker 00

  We're not sure. So anyway, I guess the point about all of this stuff, the thing that makes me, it kind of gives me a little bit of hope in a weird way, is that, in a sort of depressing way, maybe. But I think that we spend a lot of time talking about how, oh, the world might be over. We talk in sort of apocalyptic terms about climate change, about, about nuclear war, about, about all of the potential things that we could destroy ourselves with. But I think the thing is, is that actually we are talking about ourselves, right? Nature is going to be fine. The world is going to be fine. Like, it's really only us. And I think that we have this real habit of imagining that it's

• 19:30Speaker 00

  like, human-made and nature, as though there's a separation and a distinction between us. But actually, we are of this earth, right? And it's like, we're just one little element of it. And if we leave, they're going to be fine. They're going to be absolutely fine.

• 19:48Speaker 01

  Yeah, humans are just one of the many kinds of animals on earth. There are ways in which we have a responsibility. That I don't think, I don't hear discussed too often, like we, for example, if, if an asteroid was hurtling towards Earth, it's not going to be the cows that save the planet.

• 20:07Speaker 00

  No.

• 20:08Speaker 01

  That's on us.

• 20:09Speaker 00

  Yeah, yeah. And that could be genuinely apocalyptic.

• 20:13Speaker 01

  Yeah.

• 20:13Speaker 00

  For everything.

• 20:14Speaker 01

  That could genuinely end all life. It will come down to us and not the tree frogs.

• 20:19Speaker 00

  There is one place, when I was looking for areas that are closed off to humans that you cannot go to, I did find one place that I think sounds really interesting.

• 20:27Speaker 01

  Okay, what is it?

• 20:28Speaker 00

  This is one of the few examples that has not been created as, as a result of war or fighting between humans. This is a place called Ilha de Quimada Grande, otherwise known as Snake Island in Brazil. This is a place that has got so many snakes on it that it was closed off to civilians in the 1920s and has never been reopened. It's a, it's a 43 hectare island, holding around 4,000 vipers.

• 21:00Speaker 01

  Whoa.

• 21:02Speaker 00

  Each one of which has venom that is strong enough to kill you within an hour.

• 21:06Speaker 01

  Yeah. And so they get to live their own lives, free from human intervention, because we've just decided that that's how it's gonna be.

• 21:16Speaker 00

  No, thanks. I think they're also endangered. I think that's another point. This is like a particular place where they thrive and everyone's like, okay, let's just, should we just, should we just leave them? We'll just leave them alone. We'll just let them be. Let's just not go there.

• 21:28Speaker 01

  Yeah, all right. The snakes can have that.

• 21:30Speaker 00

  So maybe that's what life will be like after, after we wipe ourselves out. You know, the houses will be reclaimed by the forest within 15 years, swallowed by vines, and then eventually it will just be Snake Planet.

• 21:44Speaker 01

  Yeah.

• 21:44Speaker 00

  Do you know what? I think I'm still a bit depressed about the, the mirrors from last episode. I think maybe I'm being a bit pessimistic.

• 21:52Speaker 01

  No, that's fair enough. How excluded does a place have to be? Like, there are mountains that have still not been climbed because they are sacred to the native people. And in some cases, there are laws against anyone climbing those mountains. So there are places where nature can be untouched.

• 22:13Speaker 00

  Absolutely. Yeah. I mean, there's plenty of places, like, you know, the middle of the Sahara is, it, it may as well be untouched.

• 22:20Speaker 01

  It may as well be, but it's also, I mean, there's life there, but in, in that life is, you know, it's, it's flourishing. I mean, it's, is it flourishing or is it kind of struggling? It's there. But it made me think of places like the Trinity Site, where, where the United States did its first atomic testing. That's open to the public once a year. Otherwise, nature there gets to have its own way. But, you know, the amount of nature, things that can be done in the desert where the sand's been turned to glass, trinitite is, is limited. There are places too, where humans are excluded, like Sentinel Island, off the coast of India.

• 23:05Speaker 00

  Absolutely. Well, not all humans.

• 23:08Speaker 01

  Not all humans, just the sentilees, sentinelees. They are a culture, a tribe of people who live on this island and have made very limited contact with the outside world. I think that they were given some coconuts, maybe in the 80s or 90s, by some visitors, but we don't know their language. And to what extent they are aware of the outside world is unknown. What do they think about the airplanes they see way up in the sky? How big do they think the world is? These are things that we don't try to answer because it's been decided that they should be allowed to live their way without interference.

• 23:48Speaker 00

  They also, a couple of times, they have killed intruders, right? So people have gone there. There was a fisherman, there was a missionary, who ended up, the, the tribe were like, no, thank you very much, done. So, so yeah, the Indian government patrols it. It's, is really careful about making sure that nobody goes there.

• 24:06Speaker 01

  They are. Yeah, that missionary, that was a pretty recent story. He thought, you know, bringing the word of God to these people is my mission. And he didn't come back. His body was buried and they did try to maybe recover it, but they want to leave the sentinelees to them, to themselves, to be themselves. And there was a YouTuber who tried to go there. Have you seen this story?

• 24:29Speaker 00

  No.

• 24:30Speaker 01

  This was very recent. A YouTuber tried to sneak onto Sentinel Island to make contact with these essentially uncontacted people. And it was very, very controversial. He got arrested and finally posted his videos just a few weeks ago. And to be honest, it's not entirely clear to me that he actually went to Sentinel Island. The videos are, it's very, they're very unprofessional and un, um, serious. It's kind of like, oh, guys,

• 25:10Speaker 01

  I'm doing this for you. Whoa, do it for the vine. And then it's not obvious to me that he's actually there. He just kind of appears at, at an island, his boat's on the coast and he's like a few feet away from it. And he's like, I'm here. Okay. I don't see anything. I'm gonna go back. And then on his way back, he throws a can of Diet Coke into the water and says, it'll get washed up there. I wonder what they'll think this is. I wasn't convinced he actually did it. I'm wondering how much of this was a hoax.

• 25:38Speaker 00

  Hmm.

• 25:39Speaker 01

  Anyway, I'm heartened to see how controversial that whole stunt was.

• 25:44Speaker 00

  Me too. You don't get to make decisions for humanity on your own. Okay? No, don't do that.

• 25:50Speaker 01

  That's right.

• 25:51Speaker 00

  But there you go. Anyway, that's, I've been to two of them, two exclusion zones. I'd really love to go to Trinity, to the, to the Trinity Site.

• 25:59Speaker 01

  Yeah, my uncle has been at least once. I think he tries to go like every year.

• 26:03Speaker 00

  Is that safe?

• 26:06Speaker 01

  Well, yeah, I think for the brief time that you're there, it's, I guess, safe enough.

• 26:11Speaker 00

  Imagine if he had a necklace made of Trinity glass.

• 26:15Speaker 01

  Did you show that in a Field Notes in the past?

• 26:18Speaker 00

  No, I've, I've told you privately about how.

• 26:20Speaker 01

  You told me privately about it. You showed, you showed the, the glass that was made with lightning.

• 26:25Speaker 00

  I'm saving it until it's, saving it until it's ready. But one day, one day I will have something like that for you. Yeah.

• 26:30Speaker 01

  You've shown us two kinds of natural glass. You've shown us the glass made by lightning strikes and you've also shown us obsidian.

• 26:37Speaker 00

  Look, these are my private obsessions, Michael.

• 26:39Speaker 01

  Did you know that I gave my wife a giant chunk of obsidian for her birthday this year because of you and that episode? Yeah. I always skipped by the obsidian. My wife loves rocks as well. You guys should talk soon. But I always skipped past obsidian because I didn't know what it was. I would, actually, I, I didn't even look into it. I, I'm afraid to admit that I was a bit incurious, which I hate. But then you taught me so much about it that I'm like, whoa. So I got her this beautiful piece. And then we had to travel with it back from New Zealand. And she was like, don't get me heavy rocks for my birthday when we've got bags to pack for an airplane.

• 27:17Speaker 00

  Look, that's fair. That's absolutely fair. Did you get the one with the little dying florets in it?

• 27:21Speaker 01

  No, I didn't. I went with no florets forming yet. They had a piece like that. And I was like, oh, I don't know. I, I went with just the pure jet black piece of nice, fresh, geologically fresh piece. And I told her, hey, it's going to become a new gift. Just give it 100 million years or more. And it's the gift that keeps on giving.

• 27:42Speaker 00

  Absolutely. Yeah, too right, too right. Look, I just, I just think the stones that everyone gets excited about are really boring. I think, I think things like volcanic glass is much more exciting. All right. Thus ends my, my little foray into no-go zones. We're gonna go to a go-go zone after the break, which is gonna be your questions. How was that for a link?

• 28:05Speaker 01

  It's a lovely link. We'll see you guys soon.

• 28:22Speaker 01

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• 30:29Speaker 00

  Okay, we're back. Michael, first one for you. What is the most cosmic horror science fact that you know?

• 30:36Speaker 01

  Cosmic horror. I love this question. This one came from our subreddit, r/the rest is science. It was asked by Petros Anastasia Dis. I believe that's how you pronounce it. They asked, yeah, what is the most cosmic horror science fact I know? I guess the most scared I've been by a scientific thing was probably, I was reading Greg Egan's Diaspora, and in that story, there's a robot, like an android thing that lives on the moon by itself, and its job is to like check readings from different astronomical objects.

• 31:19Speaker 01

  And one of them are these black holes that are going to be colliding. And the readings aren't matching the theory. They realize that actually this is going to cause a very different effect than they predicted, and it's going to create a gamma ray burst that will destroy Earth. And I was like, what don't we know about the universe that could just happen? You know, like, we all feel kind of safe, like, oh, there's nothing too dangerous very close by. Gamma ray bursts don't happen that often. But we don't know every possible gamma ray burst source near us and when it will go. And if it goes, that could just be the end.

• 31:58Speaker 01

  It game over and it would just happen and we would be fried. Some of us might be able to live for a few agonizing days afterwards. But this is, this is a phenomenon where an enormous amount of gamma rays, which is the most energetic form of electromagnetic radiation, just gets shot into space and it, you know, it's going to cause immense damage.

• 32:27Speaker 00

  I mean, talking of nuclear bombs, that's essentially like a giant, giant, giant nuke going off.

• 32:32Speaker 01

  Giant, giant, giant. It is the brightest thing in the universe, right? It's, it's getting hit like directly with a, with a pulsar's pulse. It's, it's bad. And I started to think, man, that could happen in my lifetime. I mean, is that horror enough? That's kind of just more like.

• 32:53Speaker 00

  I mean, it doesn't get much worse than that.

• 32:55Speaker 01

  It doesn't get much worse.

• 32:57Speaker 00

  The thing is, is that, okay, I mean, you wouldn't see it coming because it travels at the speed of light. So it's with, so it's with you before you know. It would almost certainly kill everybody instantly, wouldn't it?

• 33:08Speaker 01

  Yeah, I mean, it all depends on the strength of, of the burst. But yeah, I think that's where the, the horror comes in, that it's not just violent. It sneaks up on you. You don't know it's coming. And once it's there, you don't know it happened because you're already gone.

• 33:23Speaker 00

  There's something about everything you've ever known and loved disappearing immediately that, I mean, I wouldn't say it doesn't bother me. But I, but I think that I could handle that. I could handle that, actually, because you just wouldn't know, you wouldn't know what hit you. Whereas I think if it was beta radiation in some way, then everyone's going to die. It's just, it's going to be much more agonizing. And you're going to see people you love decay in front of you and know that that is coming for you and there's nothing you can do about it.

• 34:03Speaker 01

  Right. At least a gamma ray burst would be sudden. Well, the point is, this whole book Diaspora, it's a, it's very hard sci-fi by Greg Egan, and it scared me. I read it mainly on an airplane. I'm already kind of a scared flyer. We've talked about this before. And I couldn't really handle it. It really amped up. One of the other terrifying things it discusses is what it's like to travel near the speed of light, such that when you get to your destination, you know, it's been a few nights, but yet a thousand years has passed on Earth. And everyone that you knew there is now gone, long gone. And you live in a different universe, basically. And it, it deals with that in ways that just boggle the mind.

• 34:44Speaker 01

  We start talking, because the characters are immortal artificial intelligences. And so they can live through a trillion years easily. And they just don't even recognize this. They, they eventually escape into a four dimensional universe, and he describes exactly how planets would orbit in such a universe, how life forms could eat in four dimensions. And it just makes you feel so alien that it scared me. I would call that cosmic horror. I highly recommend it.

• 35:20Speaker 00

  Okay, that sounds, you know, you've mentioned, you've mentioned the Egan book a couple of times. Maybe not that one, but a few of them. I need to, I need to get on it. I need to, I need to up my sci-fi game, I think. Okay, next question that came in from Liam Brain. Liam, is that your real name?

• 35:39Speaker 01

  Liam Brain. That's who listens to this podcast, everyone. Mr. Brain himself.

• 35:45Speaker 00

  You know what, though? That's a bit like, I met someone in Greece once who was called Adonis. And I thought that was a lot of pressure from his parents, you know?

• 35:52Speaker 01

  That's a lot of pressure. Anyway, Liam, you have a great name. And you asked, I'm quite interested in the tectonic plate movement of the Earth. If plates move and therefore land shifts, wouldn't the Earth decrease and increase in size? Where do the plates go when crashing?

• 36:09Speaker 00

  Great question, Mr. Brain. And really, honestly, this is like a really good instinct. This is, there was this whole theory that was built on exactly this idea, by the way, which was called Expanding Earth Theory. And some people who sort of championed it, they, they believe that, that, okay, well, the continents are drifting apart. And the reason they're drifting apart is because the, the planet must be quietly inflating beneath them. It turns out that just doesn't hold. You should really think of the Earth as more like, I mean, it's a fish, or, but it's more like you've got corks that are floating on the top of, on the top of water underneath. They're sort of bobbing around, which is what the plates are like. If they crash into each other, especially if it's two land masses that crash into each other,

• 36:53Speaker 00

  then they don't really have anywhere to go, but they're too, too kind of light. They sort of end up floating upwards, and that's how you end up getting mountain ranges. The Himalayas is a perfect example of that, where these two tectonic plates met and the Himalayas pushed upwards. And we know this for sure because you can see fossils at the top of the Himalayas, right? Like, and they're sort of in the mountains of the Himalayas. There are definitely things that used to live by the side of the sea, right? That were definitely on the edge of the coast in the past. For example, Pakicetus, one of my favorite historical creatures, which is basically a dog that is the ancestor of the whale, right? There was like a dog that was living on land and would dip into the sea

• 37:38Speaker 00

  to go and eat some fish. That is found in the Himalayas. And we know that it used to live near the, near the ocean. On the other hand, if you have a sort of two tectonic plates crashing into, into each other and they're under the sea, sort of everything's much heavier. And one of them will sink downwards and end up getting kind of destroyed and melted into the mantle below. On the other hand, if you have things that are ripping apart, which is what's happening actively in Iceland at the moment. Iceland has the two plates, the Eurasian plate and the, the Americas plate. And they are ever so slowly being ripped apart. And what happens is you get effectively the magma coming up from underneath. And this is why it's an active volcano region.

• 38:23Speaker 00

  This is, this is the reason why you're still getting all of these, the kind of bursting up as these cracks appear between the, between the two plates. There's, there's a football field, which I went to go and see in Iceland, where people were literally playing football, right? And then an earthquake started, and then a massive gigantic crater appeared in the ground over the course of like 24 hours. It's phenomenal.

• 38:47Speaker 01

  But then what, where did the rest of the plates go? When they separate, their other ends aren't just filling in empty space. The Earth is a finite sphere. So are they crunching on the other side?

• 38:59Speaker 00

  So they're either going up or going down.

• 39:01Speaker 01

  Right. So the Earth is not getting larger or smaller. It's just.

• 39:05Speaker 00

  Moving around. And, and actually, satellite images that have, have looked into exactly this, the Expanding Earth Theory, they measured that the, the Earth's radius overall stays incredibly steady. We're talking about a fraction of a millimeter a year. And this really is a question of scale, you know? When you're standing on the surface of the Earth, you sort of, this crater that appears that's, you know, a few meters wide feels absolutely enormous. But compared to the radius of the Earth, I mean, we are, they call it a crust for a reason, you know? We are right, right, right on the surface of this thing.

• 39:39Speaker 01

  Yeah, it is thin. And, I mean, the Earth is getting like more massive as space dust falls down to it. That's offset by mass the Earth loses, like really light gases, hydrogen and helium. They get up to the top and they get picked away by solar wind. And the Earth also is like radiating heat out into space, which means it does lose a little bit of mass. But overall, the falling space dust is making Earth more massive. But as Hannah said, it's like not actually growing in any noticeable way. Yeah, it's just microscopic compared to the size of the whole planet.

• 40:17Speaker 00

  Okay, last question from Oscar. Oscar says, if you had to live as either one of the first humans or one of the last humans to ever exist, which would you choose and why?

• 40:28Speaker 01

  I love this question. I want to hear your answer first, Hannah.

• 40:31Speaker 00

  Oh, I think I'd choose one of the first, basically for the same reason as your cosmic horror story earlier. I think the idea of knowing that it was coming to an end and knowing that the end was inevitable. I think it's about seeing those that you loved die around you and struggle. I think I'd just, I'd rather, no thanks.

• 40:50Speaker 01

  Well, it really depends on when and why you're the last human.

• 40:54Speaker 00

  Hmm.

• 40:55Speaker 01

  If it's because you get to sit there and watch a black hole approach and take over our solar system, that would be terrifying. But if you, if the last human is going to be alive in the year 12 trillion as a digital consciousness or in Google years or more, and it's just the heat death of the universe you have to contend with, then I don't know. You might not even have to feel things because we've evolved to some cognitive state so far and beyond. If you mean being a first person, you mean being like a very early Homo sapiens. Well, then I don't get to enjoy my favorite movies and snacks.

• 41:39Speaker 00

  That's true. You also don't have to get up when your alarm clock goes.

• 41:43Speaker 01

  Yeah.

• 41:44Speaker 00

  You don't have the hell of being like, God, have I really been doom scrolling for three hours?

• 41:49Speaker 01

  Yeah, you're saved from doom scrolling.

• 41:52Speaker 00

  Never hungover.

• 41:53Speaker 01

  Yeah, you're never hungover.

• 41:55Speaker 00

  You're never late. You're never, ever late.

• 41:58Speaker 01

  So your answer is that you would like to be one of the first humans?

• 42:01Speaker 00

  Yeah, I think so.

• 42:02Speaker 01

  Okay, well, I'm going to choose one of the last because I'd like to be there on the complete mountain of history so that I can kind of be like, okay, I want to see how the story ends, you know? I don't want to feel like I'm missing out. I just feel like those early prehistoric Homo sapiens, they must have FOMO. They must be like, guys, can you imagine? There's going to be a World Cup one of these days and we won't be around for it.

• 42:28Speaker 00

  You know what they can never say? They can never say, in my day. They can never say, back in the good old days. Because this is the only days.

• 42:39Speaker 01

  Oh, yeah, well, back in my day, oh, we did things the same because my parents were Homo erectus. No, I love, I love that. Obviously, to be scientifically correct, clearly we're joking because human evolution is, it was not this like suddenly a bunch of babies were born one year and they were all like, oh, yes, I'm a cognitive social species.

• 43:02Speaker 00

  Yeah.

• 43:02Speaker 01

  There was no like first human. There's just this smear of ever-changing organisms. But I do love jokes like that. I love thinking of, you know, five, 6,000 years ago, you know, the grandparents are like, well, back in my day, we didn't have these fences. We had to go and find our food. You kids today with your agriculture. Mmm.

• 43:28Speaker 00

  What is this newfangled pottery?

• 43:31Speaker 01

  Yeah, we just carry things in our hands.

• 43:34Speaker 00

  What do you mean you've invented a bucket?

• 43:37Speaker 01

  Back in my day, we didn't have all these words. We just grunted and looked.

• 43:43Speaker 00

  Exactly. I want that, that's what I want. That's what I want.

• 43:46Speaker 01

  I think we've talked about this before. I'm obsessed with this. I just, I spend so much time reading through people's concept of deep human history in antiquity. Like when in the most ancient literature we have, did people say anything about the way things used to be? And of course, there are no written records of like, you know, my great, great, great grandma, like, lived in a tree, you know? It happened too slowly. But the ancient Greeks did have this idea that they used to be like the nomadic tribes they were aware of, that they used to not have their infrastructure and their society.

• 44:30Speaker 01

  They were only guessing. They didn't remember this. This wasn't in living memory or oral history, but it was an idea that they believed in or at least one author believed in. So, okay, yeah, basically I'd like to be the last human and Hannah would like to be the first.

• 44:46Speaker 00

  They go between us, we sandwich.

• 44:49Speaker 01

  Everyone else.

• 44:50Speaker 00

  It's everyone else.

• 44:51Speaker 01

  All of you out there.

• 44:53Speaker 00

  Yes, our favorite way to be.

• 44:55Speaker 01

  The Hannah Michael sandwich of history.

• 44:57Speaker 00

  Well, we're the bread though, aren't we?

• 44:59Speaker 01

  Oh, yeah, we're the bread. I guess sandwiches are named after what's inside, not what's on the outside.

• 45:06Speaker 00

  The human sandwich, yeah. We're the brioche buns of humanity. Okay, well, thank you for that. What a great image to finish on. As am, you can send us your questions. The rest is science at gohanging.com.

• 45:19Speaker 01

  And you can check us out on our subreddit, r slash the rest is science. Good questions there, including that one about cosmic horror. I've got more cosmic horrors I'll be sharing in the future, so stay tuned.

• 45:31Speaker 00

  Absolutely. We'll see you next week. Thank you very much.

• 45:34Speaker 01

  Bye bye.

• 45:50Speaker 04

  Your heart can tell you a lot about your health. Apple Watch Series 12 measures your heart rate every 5 seconds with the most accurate heart rate sensing in wearable. So your vitals app, now with heart rate variability, can tell you when something is off. And your readiness score can let you know when to rest and when to push. Hear the story in every heartbeat with Apple Watch Series 12. The features described are for wellness purposes only and not for medical use. iPhone 11 or later required. Based on Apple conducted study of heart rate accuracy, August 2026. Visit apple.com slash apple watch series 12.

• 46:20Speaker 05

  Everyone's got a hard question about AI. Your job, your kids, where it's going. Anthropic was built to surface those questions and share what it finds along the way. Because there's hope in hard questions. Ask yours at claud.ai/spotify and keep thinking. That's claud.ai/spotify.

• 46:44Speaker 01

  Stonefire Naan is made with real buttermilk and ghee. It's the perfect flatbread for any occasion.

• 46:50Speaker 06

  I put out Stonefire Naan with dips at every dinner party.

• 46:53Speaker 02

  I make naan-grilled cheese when my daughter has friends over.

• 46:56Speaker 01

  I use Stonefire Naan to reward the humans who do my bidding.

• 46:59Speaker 06

  Right. It's perfect for camping trips.

• 47:02Speaker 01

  Dance for it, feeble mortal.

• 47:04Speaker 06

  Sorry, is he talking to me or?

• 47:07Speaker 01

  Dance. From our tradition to yours. Stonefire. Together we Naan.