Growth

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Speaker 17 to Radio Lab. Lab.

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Speaker 21 Okay, so we're going to begin with producer Matt Kilty.

Speaker 22 Okay, Latzif.

Speaker 23 Let me take you to the land of the midnight sun.

Speaker 25 Whoa, is that Japan?

Speaker 26 No. No, rising sun is Japan.
Oh, the midnight sun's probably got to be Antarctica or something.

Speaker 27 Alaska?

Speaker 28 Alaska.

Speaker 16 Oh, do you see the mountains all the way out there?

Speaker 29 Those are snowy.

Speaker 23 That's beautiful. Specifically.
Jagged mountains kind of everywhere. Palmer, Alaska, which is like an hour north of Anglo.

Speaker 21 I've never heard of it.

Speaker 23 Yeah, it's a little town where they host

Speaker 30 every summer

Speaker 31 the Alaska State Fair.

Speaker 32 Got a wallet. I have a phone.

Speaker 29 Okay.

Speaker 33 Which is where I went last August with

Speaker 23 my childhood best friend, Mike Gladney. So I'm pretty excited.
And Mike and I were from Minnesota, which has a really big state fair.

Speaker 6 Alaska's like a small county fair.

Speaker 23 It's a little bit smaller, but

Speaker 23 it does have a lot of good food.

Speaker 21 Oh, right there.

Speaker 23 A lot of classics, but also

Speaker 27 Alaska crab cakes.

Speaker 23 A lot of great seafood. Salmon case of.
And then, of course, games, rides.

Speaker 23 But

Speaker 35 Latiff.

Speaker 16 Yeah.

Speaker 23 This little fair does have something very, very,

Speaker 28 very big.

Speaker 23 Which is the annual great pumpkin way off.

Speaker 18 Ooh, so this is like competition, like a state fair competition.

Speaker 23 That's right, a competition to see who can grow the biggest, heaviest pumpkin in the state, but also maybe in the world.

Speaker 37 Okay.

Speaker 33 Because in Alaska. You grow the best pumpkins in Alaska.

Speaker 38 You grow the biggest pumpkins around.

Speaker 23 Yeah, I know. Why is that?

Speaker 39 I think they put milk in them.

Speaker 20 They just water them with milk the whole time.

Speaker 28 That's what I heard.

Speaker 23 Mike and I talked to one of the workers, Kathy Liska.

Speaker 41 This is my 31st year working in the crops department, and I've seen maybe, I think, about 25 Guinness World Records.

Speaker 25 Wait, pumpkin specifics?

Speaker 20 No, no, no, no, all sorts of stuff.

Speaker 21 Carrots, beets, cabbages.

Speaker 41 What's Alaska, you know, what's the fair known for? It's the giant vegetables.

Speaker 23 Because in Alaska, the land of the midnight sun, plants can get a ton of sunlight. And so essentially you can grow these plants to like really, really big sizes.

Speaker 41 There's a lot of growers all around the world that'll be keeping their eye out around here to see what's going on.

Speaker 23 So, okay, wait, we should describe what we got. We got it.
Mike, Kathy, me. You call it a barn, farm.

Speaker 41 That's an open-air arena, yeah.

Speaker 34 This is our ag building.

Speaker 23 We're standing in the ag building. Smells like not good in here.
And we are standing inside this like cattle pen, this little fenced-in area. We are surrounded by bleachers.

Speaker 34 So here we are, center ring.

Speaker 30 When out comes

Speaker 28 the oh my god, oh my god.

Speaker 31 This huge

Speaker 32 gigantic. It's gigantic.

Speaker 30 Orange pumpkin.

Speaker 6 It's intimidating looking.

Speaker 23 Kathy, is it okay if I touch the pumpkin? And this pumpkin.

Speaker 45 You feel the magic?

Speaker 23 You're touching it too. It's about the size of a Volkswagen beetle.

Speaker 29 Wow. It's got like a heartbeat.

Speaker 45 Oh, it does actually wait. It's alive.

Speaker 3 It's just so big.

Speaker 23 Except it's like lumpy and like kind of blobby.

Speaker 14 Like job of the hut, kind of.

Speaker 18 Yeah. Could you and Mike have fit in the pumpkin?

Speaker 23 We could have crawled inside the pumpkin and held each other. Weird.

Speaker 38 That's 98 days old right there, that pumpkin.

Speaker 23 So the pumpkin belongs to to this guy, Dale Marshall of Anchorage.

Speaker 38 Yeah, I'm about sick of that thing, tell you the truth, you know?

Speaker 23 He's a seasoned grower.

Speaker 38 Are you pleased with your pumpkin this year?

Speaker 47 Oh, yeah, just getting one here. It's half the battle, you know?

Speaker 23 Like, when I see something this big, I'm like, this is frightening.

Speaker 47 I like it. I like the color.
You know how long it took me to paint all those little spots on there?

Speaker 23 And while we're talking, okay, oh, oh, they're putting a thing. Dale rushes over to his pumpkin.
Something's happening.

Speaker 16 Here we go. Here we go.

Speaker 23 And basically, Michael, get over here, Mike. Mike and I get in position, and then we watch them as they push this pumpkin so it's underneath this crane.

Speaker 23 And Everybody looks like they're excited, they're anticipating. And dangling from the crane.

Speaker 48 Bated breath are these straps.

Speaker 16 Everyone's circling.

Speaker 23 Okay, Dale's getting the straps ready. Dale takes the straps from the crane, wraps them down around the pumpkin.

Speaker 23 Pumpkin appears to be strapped in there, securing the rope, ties it all together with a rope.

Speaker 21 This is nerve-wracking. And then...

Speaker 21 You could hear a pin drop in here.

Speaker 23 The crane begins. The straps are tightening to lift the pumpkin.
Here we go.

Speaker 29 It's up.

Speaker 22 It's up off the pallet.

Speaker 23 If it's off the pallet. Up into the air, so it's dangling like two feet off the ground.

Speaker 23 And then... Jody, careful, Jody.

Speaker 23 Yep. A volunteer named Jodi gets on her back, climbs underneath this pumpkin.
So it's just dangling above her, and she inspects the pumpkin for like any holes, any tampering. All right.

Speaker 23 She gives a thumbs up.

Speaker 30 Jodi's a wild woman. And then...

Speaker 48 Okay, all right.

Speaker 23 They're transporting it over to the scale. The crane begins to lower the pumpkin onto this huge metal scale.
Okay, all right. They're taking the straps off and the rope.
All of it's coming off.

Speaker 28 Wow. Okay.

Speaker 6 It's fully on the scale.

Speaker 23 Dale steps back from his pumpkin. It's on the scale.
It's being weighed.

Speaker 29 Okay.

Speaker 23 And then...

Speaker 24 The moment of truth.

Speaker 29 Alright, here we are.

Speaker 23 Oh, my God. 2,000 pounds.
Oh, my God.

Speaker 29 Oh, my God.

Speaker 23 First place, grand prize-winning 2,035-pound pumpkin.

Speaker 16 Oh my god. Oh, my God.

Speaker 30 To put that into perspective,

Speaker 23 that is about eight to ten panda bears. Okay.
Just to give you a sense of the the weight. All right.
A lot of pandas. Anyway.
High fives all around for Dale. Dale's sake.

Speaker 23 Dale's got his arms in the air. He's running around his pumpkin.
How are you feeling?

Speaker 47 Well, I'm ecstatic.

Speaker 47 That's about 150 pounds more than I thought I was going to get.

Speaker 21 And then pretty quickly.

Speaker 28 Moving it. We're moving it.

Speaker 29 We're moving it. I'm out of here.

Speaker 28 I'm out of here.

Speaker 23 The local news crews around to Dale. He gets a ribbon, $1,000.

Speaker 23 And then

Speaker 23 that's

Speaker 42 pretty much it.

Speaker 22 Okay.

Speaker 32 Yeah, that's kind of everything.

Speaker 50 Huh.

Speaker 21 And And was this a record-setting pumpkin then?

Speaker 29 No.

Speaker 23 Actually, it didn't even beat Dale's previous pumpkin record in the state.

Speaker 23 But it was a good pumpkin, first place pumpkin.

Speaker 14 But then, like, what happens to the pumpkin afterwards?

Speaker 23 Well, Dale typically takes his home. He says his grandkids like to play on it.

Speaker 23 And or if you don't do that, you can donate it to the Alaska Zoo or the Wildlife Conservation Center where they will feed it to bears.

Speaker 21 Bears? Yeah, grizzly bears.

Speaker 6 That feels like an Alaska punchline joke that you would make up.

Speaker 27 Right?

Speaker 25 No, it can't feed bears.

Speaker 29 It is bears.

Speaker 6 Because it's not fit for human consumption?

Speaker 51 Or is like, could you eat these?

Speaker 23 Yeah, yeah, you can eat them. I don't think they taste very good.

Speaker 29 The figure they get.

Speaker 30 They're not being grown for flavor.

Speaker 25 It's just so hard to imagine the point of this.

Speaker 21 What do you mean?

Speaker 16 Like, what are we, what?

Speaker 23 What are we doing?

Speaker 37 What are we doing here?

Speaker 23 Well, I mean, if you're, for the growers, I think it's just like, it's like pushing the limits. Like, like just you're trying to grow something really stronger, faster, bigger, better.

Speaker 23 Yeah, exactly. But I think for us to be there, like, if you average it out, Dale's pumpkin grew 20 pounds a day.

Speaker 33 And to just come

Speaker 23 and look upon that.

Speaker 53 I think it's cray cray.

Speaker 23 To see something that's just so incomprehensibly big.

Speaker 53 I think it's crazy how big it is.

Speaker 21 It just stirs up.

Speaker 51 Look how big that thing is.

Speaker 23 This real sense. It's gorgeous.
I think it's beautiful.

Speaker 28 Really?

Speaker 41 I do. Because it's so big.
I mean, where else do you see something like that?

Speaker 23 Because seeing something like that just sort of makes you think about the fact that everything

Speaker 23 has this blueprint for growth, for how it's supposed to grow, for what it's supposed to grow into. And yet, here you are confronted by something that seemingly doesn't fit that blueprint

Speaker 28 at all.

Speaker 23 And that is what we're doing there, Latif.

Speaker 23 Coming together to feel a little bit of joy, a little bit of terror, brought on

Speaker 23 by an enormous pumpkin.

Speaker 50 Okay. All right.

Speaker 34 Sure.

Speaker 31 All right. This is Radiolab.

Speaker 27 I'm Lulu Miller.

Speaker 26 I'm Luftiff Nasser.

Speaker 33 And today we are looking at Growth,

Speaker 6 which is actually an episode we started working on when you were off.

Speaker 29 growing a person.

Speaker 33 Yeah, actually, my belly was just like that pumpkin.

Speaker 30 It was like bigger and bigger.

Speaker 31 I just tie my toes or tie my shoes.

Speaker 33 And then the baby came out and she has already doubled in just a few months. She's already doubled in size.

Speaker 25 But we have more.

Speaker 6 This is not an hour about pumpkins, as much as I know you would have wanted that.

Speaker 20 We have three different stories about growth.

Speaker 3 Growth that happens in places you'd never expect. Growth that follows a pattern that seems woven into the universe itself.

Speaker 51 And even a growth that has taken over the whole planet and, for better or worse, the surprising thing that might stop it.

Speaker 37 All right.

Speaker 40 Let's do this thing. Yeah.

Speaker 26 First up, we have a story from Becca Bressler.

Speaker 45 Hello.

Speaker 53 Hey. Okay, so I'm going to take you from pumpkins to carrots.

Speaker 28 Okay.

Speaker 25 Huge leap, huge leap.

Speaker 26 Orange vegetable to orange vegetable.

Speaker 53 Stick with me. This story starts in the kitchen.
Okay.

Speaker 54 So this was a few years ago, November 30th, 2021, With this woman named Ray Mondo. All of my housemates were away for the evening and I was making dinner.
I have vegetables out.

Speaker 17 There's broccoli, there's carrots.

Speaker 53 Music is playing. Vibes are good.
Pretty normal evening.

Speaker 43 And as I'm chopping, chop, chop, chop, chop, chop, chop,

Speaker 43 all of a sudden,

Speaker 53 she looks down and was like, I just cut off my fingertip.

Speaker 53 The end of her left middle finger from halfway down the nail was just gone.

Speaker 44 The wound was just white for a moment, and then I saw just like the river of blood like rise.

Speaker 53 So she grabs a paper towel, presses it up against her finger that's gushing blood. Oh, and she immediately calls her friend Amy.
My best friend, Amy, used to be a trauma nurse.

Speaker 14 Person to call, right person to call.

Speaker 44 So Amy picks up, they tell Ray to bandage it, keep pressure on it, go on the couch, elevate it, and just like dissociate for a while.

Speaker 25 Wait, but she didn't go to the ER or something?

Speaker 53 So, actually, that was the question that consumed her.

Speaker 54 I'm like, how much is having a fingertip worth to me? Like, can I put a dollar amount on it?

Speaker 53 Her deductible was super high.

Speaker 54 If the emergency room bill were going to be $5,000,

Speaker 57 not, I'm good.

Speaker 54 Like, I can live life without a fingertip.

Speaker 54 If it's $1,000,

Speaker 17 I'm like tempted, but like, geez.

Speaker 53 Yeah.

Speaker 43 I do really like having like all my fingertips.

Speaker 16 Like,

Speaker 53 but eventually she decides it's not worth it.

Speaker 30 No.

Speaker 44 And at that point, I was like, I'm done.

Speaker 54 I have a short middle finger now.

Speaker 53 This is just my life. Yeah.

Speaker 19 But

Speaker 53 over the next few days, as Ray gets into a routine of changing out the bloody bandage, she starts to notice a couple things happening.

Speaker 15 Uh-huh.

Speaker 43 One, what I noticed was my fingernail continued to grow outward

Speaker 57 in the same shape that it grew before.

Speaker 54 And two, the finger started to fill in underneath the fingernail that was growing outward.

Speaker 44 And after a few weeks, I was like, wait a minute, like...

Speaker 43 Is my fingertip growing back?

Speaker 54 And

Speaker 42 slowly but surely it was just sort of like

Speaker 43 my finger was back

Speaker 7 What?

Speaker 27 Like her whole fingertip grew back? Yeah. Like you couldn't even tell if anything happened to it?

Speaker 20 No.

Speaker 57 Now it's like, I would say 99.5%

Speaker 43 back to normal.

Speaker 27 Man, this feels so like, I mean, I've heard of human, like, you can regrow skin.

Speaker 21 I get that.

Speaker 6 I feel like I've vaguely heard of someone regrowing part of a liver back, maybe.

Speaker 37 Yeah.

Speaker 51 But, like, this is

Speaker 51 different.

Speaker 16 This is like, there's a whole, there's a bone in there.

Speaker 51 There's, like, there's so much going on.

Speaker 53 Yeah, it, it does feel more complicated.

Speaker 25 There's layers.

Speaker 6 It's a, it's a, it's a flesh of lasagna that you're growing back.

Speaker 53 Actually, totally. I had never heard of this before.
And obviously, this was very surprising to Ray.

Speaker 42 Oh, totally.

Speaker 53 And so actually, she emailed us to tell us about this.

Speaker 25 To be like, what?

Speaker 34 I mean, how?

Speaker 61 Like, am I a mutant with superpowers?

Speaker 53 Kind of, yeah. She wanted us to find out, how did this happen? Like, how did my fingertip grow back?

Speaker 55 Right.

Speaker 53 So Ray and I together called up.

Speaker 39 It's nice to meet you, Ray.

Speaker 33 Oh, it's so nice to meet you too.

Speaker 53 This guy.

Speaker 39 Can I see your finger?

Speaker 34 Oh, yeah. Before you go.

Speaker 53 So this is Ken Munioka. He actually studies fingertip regeneration.

Speaker 39 Currently at Texas AM University.

Speaker 53 And Ken wasn't that surprised to hear about Ray's fingertips.

Speaker 39 I felt bad for you, but I suspected it all came back.

Speaker 53 He says that people have been writing about this for nearly 100 years.

Speaker 62 Yeah.

Speaker 39 That story begins back in the 1930s. A physician in Canada had a severely infected finger, and he basically removed the bone out of his finger.

Speaker 53 Just the tip of it.

Speaker 39 And he, he, but he x-rayed it, and he sort of followed it with time and he found out that his whole finger regenerated.

Speaker 53 Whoa. Ken also told us that back in the 70s, doctors in the UK saw a bunch of kids with chopped-off fingertips.

Speaker 39 There was a reasonable number of them coming into the clinic.

Speaker 53 No idea what was going on over there, but...

Speaker 39 They documented hundreds of children regenerating their fingertips.

Speaker 53 So Ken studies this stuff at a microscopic level.

Speaker 39 In fact, I spend most of my time working with mice.

Speaker 53 Unfortunately, or fortunately, there aren't a lot of controlled studies around chopping off human fingertips and seeing how they grow back. But thanks to our good friends, the mice.

Speaker 39 We were able to follow the regeneration process using this machine called a micro CT.

Speaker 53 What's that?

Speaker 39 So it's like a CT scanner, but it's like for tiny little things.

Speaker 53 And Ken says that when you cut off your fingertip, a few things happen.

Speaker 39 You know, the initial response to a trauma like that is an inflammatory response that cleans up the wound.

Speaker 53 Pretty standard stuff. But then sometime after that, something very unusual happens.

Speaker 32 Stem cells that are in the nail bed that are normally required for having your nails grow continuously throughout your life, they sort of kick off this rebuilding process.

Speaker 32 Forming this sort of organizing response to make the other parts of the tissue in that lost fingertip.

Speaker 53 So, this is Chris Arnold. He's a professor at West Virginia University.

Speaker 32 In the biology department.

Speaker 53 And he says that these stem cells under the nail call up a bunch of other stem cells in the body.

Speaker 39 You know, cells that can make bone, skin tissue, nerves, muscle tissue.

Speaker 53 And so these different types of cells basically start regrowing what was lost. And eventually you have a whole brand new fingertip.

Speaker 30 Huh.

Speaker 61 Like we plumped back out to what it was. Yeah.

Speaker 53 How does it know when to stop? right? Like if your fingertip grows back, it doesn't become bigger than it was before.

Speaker 39 There's apparently there are signals to stop regeneration, but we don't know exactly where it's happening, when it's happening.

Speaker 53 Got it.

Speaker 63 Weird.

Speaker 21 Also, can I just say, what a weird use of stem cells.

Speaker 1 It's like you have these miracle cells in your body that can do whatever, regrow whatever.

Speaker 20 And then it's like, okay, you know what we need you for?

Speaker 61 Just keep regrowing nails that we're going to have to cut anyway.

Speaker 25 Seems like so futile, right?

Speaker 53 So, yeah, so that's exactly what I said to Chris. Yeah.

Speaker 32 So it doesn't make a lot of sense for us, right? As like, why is it our nails like just keep growing and growing?

Speaker 32 But if you think a little earlier for earlier mammalian ancestors, maybe that's where you actually get more of the answer of why this is happening.

Speaker 32 Because, I mean, from our earlier sort of kind of rodent-like ancestors, known for their ability to dig, burrow into new environments where you're getting this constant damage.

Speaker 32 And so that may came along with it, this ability to constantly regrow from that damaged kind of part.

Speaker 50 Wow.

Speaker 53 It's kind of crazy to just like look down at them and be like, I have these because of rodents.

Speaker 63 Exactly. Yeah.

Speaker 21 Like, should I use them and burrow?

Speaker 27 I don't know. Yeah.

Speaker 21 Are you burrowing with them? Like, well, what are you, what are you using your nails for? I know. Really?

Speaker 33 I'm never going to look at my fingernails the same.

Speaker 31 It's like the former us hunched over trying to dig away.

Speaker 53 Yeah. But when Chris started telling me about other animals.

Speaker 32 there's animals that regenerate even better than that.

Speaker 53 I realized that we're not that impressive at all.

Speaker 32 Yeah, so if I could regenerate like a salamander, if I cut off my hand, a new hand would grow back in its place.

Speaker 53 And as he told me about more and more of these creatures, it just kept getting weirder.

Speaker 32 Like our friend the planaria.

Speaker 53 Mm-hmm. So there's this tiny little flatworm called a planaria.

Speaker 32 And if you cut it into small pieces, even hundreds of them. Those pieces can regenerate the entire animal over again.

Speaker 50 Wow.

Speaker 32 So the whole body can grow from any part.

Speaker 53 Some starfish can also do this.

Speaker 53 You can cut off one of their arms and that can become a whole new starfish.

Speaker 32 There was a famous story where scuba divers were trying to get rid of a starfish population in their area by going down and cutting them into little pieces, only to find to their dismay that the next day they were, well, the next few weeks, they're even more starfish than they started with.

Speaker 53 Okay, now this is my favorite thing. So you know the classic one, lizards, right?

Speaker 16 Right.

Speaker 53 How they can break off their tails and grow them back.

Speaker 27 Yeah.

Speaker 53 what's amazing though is that they have this tear away sight on their tail kind of like i think of like the perforated part of like a ketchup packet or something it's like a coupon exactly but they're not the only animal that has one of these the sea slug oh but it's not the tail they're losing they actually lose all of their body from the neck down it turns out that when they're sick they can just shed their entire body and at the end it's just a head that's swimming around that will then go on to regenerate all the rest.

Speaker 50 Oh my God.

Speaker 16 Wow.

Speaker 2 I've been sick over the last few weeks, and that is just so relatable.

Speaker 3 Like, I have thought about doing that so many times.

Speaker 22 No, I'm coughing.

Speaker 33 It is wild that you can just dispense of a body and be a head and then grow a new body. I mean, when it goes to that level, it feels like, it does feel like a superpower.

Speaker 53 No, totally. And I know these things feel like superpowers to us.

Speaker 32 Yeah, we generally think of animals more like a planaria, something that could regenerate its whole body as just something sort of weird and alien.

Speaker 53 But Chris told me that this thing that seems just like a strange little cork of nature is really not that strange at all.

Speaker 32 When we look at the tree of life, the ability of an organism to regenerate itself from a small piece, whole body regeneration, the most extreme form of regeneration, that is actually very widely distributed throughout the tree of life.

Speaker 15 Wow.

Speaker 32 And it's only been lost in a couple of branches. Ours is one of them.
And so it's not really weird that an animal can regenerate its whole body. It actually might be more weird that we can't.

Speaker 51 Why can't we do this, though?

Speaker 25 Like, why are we the ones left out?

Speaker 53 Yeah, I mean, scientists think that it's because we're complex, right? Like, they typically see these regenerative properties in simpler organisms.

Speaker 32 The more complex, complex, the more many parts there are to a structure, the more interdependent those parts are. It makes sense that if you lose a part of that, it's really hard to recreate it.

Speaker 33 It's like a devil's bargain thing.

Speaker 31 Like, this is the price you pay for complexity.

Speaker 53 Yeah, it's the price we pay for like having our big old brains and

Speaker 26 it costs away more to fix a fancy car, you know what I mean, than an off-the-shelf thing.

Speaker 25 Yeah. Yeah.

Speaker 30 Totally.

Speaker 33 You know, I am curious,

Speaker 33 what does Ray think about all this?

Speaker 33 You know, how does this reporting change her? Because she wrote to you feeling like she had a superpower. And now you've told her that not only doesn't she,

Speaker 33 we pale in comparison to what most animals can do, that we are the outliers. We're the odd men out of being unempowered.
Does it, did it, did it change her sense of specialness?

Speaker 42 I mean,

Speaker 43 I don't think I feel less special. I think I feel

Speaker 43 way more connected to the tree of life.

Speaker 43 Like, oh, I got to experience this thing that like

Speaker 20 all the other, like, or like so many of the other, maybe the majority of the other, like, branches of the tree get to experience.

Speaker 54 And, like,

Speaker 33 how cool that, you know, it was just a fingertip, but like,

Speaker 31 I'm out there with all those other guys.

Speaker 53 Yeah. Yeah, you're in good company.

Speaker 54 Yeah, you know, before this story, I would not have associated my fingertips with sea slugs in the slightest.

Speaker 43 But I hope that going forward, that is what I continue to think of when I look at my fingers. I don't even know what sea slugs look like.

Speaker 43 I'm going to have to go home, look at a picture of them, and then just like hold my fingertip up next to it and be like, that's me.

Speaker 16 Yeah.

Speaker 4 Producer Becca Bressler.

Speaker 20 We're going to take a quick break.

Speaker 14 And if you don't know what a sea slug looks like, or even you think you do,

Speaker 18 just look it up during the break because they're,

Speaker 14 I mean, it's like a Martian fashion show down there.

Speaker 5 So beautiful, so strange.

Speaker 34 We'll be right back with two more stories of growth.

Speaker 59 Hey, I'm Molly Webster, and this is an ad by BetterHelp.

Speaker 59 So it happens every year, the seasons are changing, the days are getting shorter, and basically, once it becomes dark outside of my window, I feel like the rest of the world disappears, and I'm just alone, and there's nothing left to do but watch television.

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Speaker 73 It's 1972. A young British family is attempting to sail around the world when disaster strikes.
Their boat is hit by killer whales and it sinks in seconds.

Speaker 73 All they have left is a life raft and each other.

Speaker 73 This is the true story of the Robertson family and their fight to survive, hosted by me, Becky Milligan. Listen to Adrift, an Apple original podcast produced by Blanchard House.

Speaker 73 Follow and listen on Apple podcasts.

Speaker 20 Hey, I'm Lothif Nasser.

Speaker 27 I'm Lula Miller.

Speaker 18 This is Radiolab.

Speaker 3 Today's episode is about growth.

Speaker 33 Pumpkins that can grow 20 pounds a day.

Speaker 27 Fingertips that miraculously grow back after they've been chopped off.

Speaker 33 Slugs that can chop off their own body and then grow the whole thing back.

Speaker 3 This growth I have at the bottom of my toenail.

Speaker 75 Yeah, so they're obviously all different kinds of growth, but it seems like they must be like tied together by some underlying rules of nature.

Speaker 37 Oh, hello, Pat.

Speaker 65 Hi, I am here.

Speaker 62 I've invaded your host intro.

Speaker 25 Okay, great. This is Pat Walters.

Speaker 6 He's our managing editor.

Speaker 75 Yeah, and whenever we get curious about the rules governing nature and the universe,

Speaker 65 we tend to call this one particular guy.

Speaker 40 Hey, old man. Hey, how are you? This is actually very comfortable here.

Speaker 16 Let's talk all day. His name is Steve Strogatz.

Speaker 40 I'm a mathematician and math professor at Cornell University.

Speaker 62 Also has a great podcast called The Joy of Why.

Speaker 65 And I asked him, just like, what are the different ways things can grow?

Speaker 16 Okay, here we go.

Speaker 40 There's linear growth.

Speaker 76 A simple kind of growth, basically adding.

Speaker 40 Like one, two, three, four.

Speaker 76 This, if you're like me, is how that stack of magazines grows on your desk each month.

Speaker 16 And then there's exponential.

Speaker 40 Growth that feeds on itself.

Speaker 74 The kind of growth that multiplies.

Speaker 40 Like one, two, four, eight.

Speaker 76 Picture each magazine on the stack giving birth to another issue of the magazine each month.

Speaker 40 No, the more of something there is, the faster it grows.

Speaker 49 This, of course, is how diseases spread and pandemics happen.

Speaker 40 Now, there are kinds of growth that are faster than exponential.

Speaker 16 What's that?

Speaker 40 There's something called blow-up.

Speaker 16 What's blow-up?

Speaker 40 Which sounds like what it is.

Speaker 16 Something goes from nothing

Speaker 40 to infinity in a finite amount of time.

Speaker 16 But Steve says this doesn't actually happen in the real world.

Speaker 40 Because we don't believe there are infinite anythings in our existence.

Speaker 50 Oh, thank God.

Speaker 28 And then there are these other kinds of growth that are a little more, I don't know, peculiar.

Speaker 16 And Steve told me about this one that completely took me by surprise and showed me how these patterns, these invisible blueprints of growth, can sometimes stretch out and connect parts of the world that I didn't think had anything to do with each other.

Speaker 40 So you've heard the name Fibonacci. There's the famous Fibonacci sequence, which is where I take a number like one and two, and then I add them to make three.

Speaker 40 And then I always take the two most recent numbers and add them to make the next number. So two plus three is five.
5 plus 3 is 8.

Speaker 40 Where am I? 8 plus 5 is 13. These are all Fibonacci numbers, and you can keep going like that, and you can see they're getting big.

Speaker 65 So the sequence goes 1, 2, 3, 5, 8.

Speaker 74 And each number in the sequence is the sum of the two that came before it.

Speaker 33 So it keeps getting bigger in this strange and yet oddly

Speaker 33 predictable way.

Speaker 29 Yeah.

Speaker 76 And I think when I started talking to Steve about it, I had the vague sense that what was interesting about it is that it sort of shows up in nature,

Speaker 50 maybe in plants.

Speaker 37 Yeah.

Speaker 32 But according to Steve.

Speaker 40 The Fibonacci sequence was originally posed as a problem about rabbits growing, where there was some made-up population biology rule about how many rabbits give birth to how many other rabbits that led to the Fibonacci sequence.

Speaker 40 That's from 1200 A.D.

Speaker 40 And it's not even...

Speaker 35 They observed something in rabbits or something.

Speaker 40 No, it's a made-up, it's a textbook problem. It's fake.

Speaker 40 rabbits don't really grow according to the fibonacci sequence wait a minute so they came up with the where did the where did the sequence come from well it's got a good backstory um yeah what's that so so fibonacci

Speaker 74 uh fibonacci whose real name was leonardo but of pisa not of vinci weirdly steve says a historian sort of randomly stuck him with the name fibonacci in the 1800s but all this happened about 600 years before that when he was still just leonardo of pisa

Speaker 40 So Leonardo of Pisa

Speaker 40 is an Italian mathematician whose dad was working in North Africa. It's a really interesting, vibrant place.
He's getting to meet people from Egypt and all over the Middle East as well as Sicily.

Speaker 40 And there's a lot of trading going on. It's 1200, a very vibrant time in the Middle Ages.

Speaker 40 And this Leonardo learns about a fantastic new kind of math that has come from a different part of the world, from the traders coming from the Middle East, from Arabic world, including who have themselves learned math developed in India.

Speaker 40 And so when we talk about Hindu-Arabic numerals, the ones that we all use today to write with, 0, 1, 2, 3, up to 9, those digits are from India by way through Baghdad and finally into Europe through dun, dun, dun, Leonardo of Pisa.

Speaker 40 Fibonacci brought Hindu-Arabic numerals to Europe.

Speaker 40 So this, it's a really ironic thing that Fibonacci gave us the numbers that we all use today, and nobody really remembers that that's what he did.

Speaker 40 He wrote this book called Liba Rabachi, basically the book of counting, the book of reckoning, how to work with numbers in a really practical way that merchants of the type that he was encountering in all these trading spots in the Middle East, everybody had to work with money, and Roman numerals were terrible.

Speaker 40 So everybody wanted a better way, and these Hindu-Arabic numerals were fantastic. You could do really good calculations in your head.

Speaker 40 So anyway, he introduced this fantastic system of Indian numerals to Europe around 1200.

Speaker 40 And he just, as a little footnote in his book, not really a footnote, but the book is filled with practice problems about taxes, about interest, about all kinds of money problems.

Speaker 40 But he made up this problem about growth, that the rabbits take one month to mature, and then when they mature, they give birth to another set of rabbits a pair of rabbits and then that pair can mate blah blah blah anyway he made up this story about rabbits where the Fibonacci sequence comes out where did this but the sequence even though he he applied it to a made-up story about rabbits but but but don't we see the Fibonacci sequence yes represented in yeah yeah yeah we totally do sure plants really do have it I mean there's a million places we could go we could if you look at a pine cone if if if you start following the straightest line that you can, you can make a certain number of windy spirals.

Speaker 40 So if you count them up, the number will end up being a Fibonacci number of these spirals. And no matter how you do it, you'll always get a Fibonacci number.
Trevor Burrus, Jr.

Speaker 36 So

Speaker 35 did he just wing it and throw it on some rabbits and then it turned out magically to be true?

Speaker 36 Or did it

Speaker 16 come from India?

Speaker 40 Well, okay, that's another good story. It's nice of you to keep asking me these kind of questions.
Okay, so it turns out that Fibonacci was not the first to think of the Fibonacci sequence.

Speaker 48 Oh.

Speaker 40 It's a misnomer, and we're only gradually starting to appreciate how much of European math is really Indian math or Arabic math. I mean, a lot of it is European.
I don't want to pretend it's not.

Speaker 40 But the Fibonacci sequence was known 400 years before Fibonacci, if not longer,

Speaker 40 in India. And in a really surprising place.

Speaker 40 It's in connection with poetry.

Speaker 40 With poetry. Yeah, let me, can I try to explain it to you? Yes.
This will take a minute.

Speaker 37 Okay, yeah, do it.

Speaker 40 We can try.

Speaker 7 Yeah, okay.

Speaker 40 So going way back a few hundred years before the birth of Christ, there are scholars in ancient India who are really interested in, let's call it meter, you know, like rhythm, patterns of rhythm in poetry.

Speaker 40 The poems have certain rules to them because the rules make it easier to remember. And in a time before people had books, because remember the printing press is in the future.
Oh, right.

Speaker 16 Right.

Speaker 40 So like if you want to remember the Odyssey in ancient Greece or memorize the Koran, you're going to sing it.

Speaker 36 So it's not just because it sounds nice or is pretty, it's because it's a tool for remembering.

Speaker 40 It's the way human psychology works. Right.
So

Speaker 40 these ancient scholars in India were trying to just think what exactly are the possible patterns if we obey,

Speaker 40 if our poetry obeys a certain rule, which is that you can build it out of two types of syllables. You can have something that lasts one beat.
or something that lasts two beats.

Speaker 40 And so one question that people interested in the sort of the science of poetry were concerned with was,

Speaker 40 suppose I want to make a line that is, for example, four beats long. How many different ways can I make something that's four beats?

Speaker 40 Basically, I have two things I can play with. Something that's one beat long or two beats long, right? There's these two kinds of syllables.

Speaker 37 So I could do one plus one plus one plus one.

Speaker 40 That adds up to four.

Speaker 40 Or I could do a rhythm that was

Speaker 40 two one one.

Speaker 30 That would also add up to four.

Speaker 40 Or I could do one two one.

Speaker 40 That would be four. Or I could do two two.

Speaker 40 Or I could do 1-1-2.

Speaker 40 I've said five possibilities.

Speaker 40 Now, what's interesting about that is that five is the fourth Fibonacci number.

Speaker 15 Oh.

Speaker 40 And in general, if I want to make something that's n beats long, there is the nth Fibonacci number ways of doing it.

Speaker 16 Whoa, wait. Okay.

Speaker 78 So to make a five-beat line, there would be eight ways of doing that. And to make a six-beat line, there there would be 13 ways of doing that.
Yes.

Speaker 75 And a seven beat line, there would be 21 ways of doing that.

Speaker 40 It's a growth problem, right? It's the growth of possibilities. It's the growth of creative possibilities in Sanskrit poetry.

Speaker 40 This was figured out in India by a person named Virahanka four centuries before Fibonacci was born.

Speaker 37 Wow. Yeah.
So

Speaker 75 they noticed this phenomenon present in poetry, studying the possibilities in Sanskrit poetry.

Speaker 7 And then like when I Google the Fibonacci sequence and Wikipedia tells me it's like really all over nature, not just in pine cones, but pineapples and on sunflower seeds.

Speaker 35 Apparently lots of flowers have a Fibonacci number of petals.

Speaker 16 Yes.

Speaker 65 I'm just now trying to like wrap my head around like, is that because there's something

Speaker 65 in the universe that like made its way into the Sanskrit poetry by way of humans that also made its way into the trees and the pineapples.

Speaker 19 And like, what's the, that's crazy, that's wild because I think about poetry as being so separate from a pineapple or

Speaker 77 the leaves on a tree.

Speaker 48 Yes.

Speaker 16 Well, okay.

Speaker 49 It's not a question.

Speaker 35 That's just

Speaker 40 an expression of wonder, which is appropriate. Why are Fibonacci numbers in botany? Why are they in so many plant structures?

Speaker 40 There are various theories out there.

Speaker 40 Some people will say that it has to do with like when a branch shoots out of a tree, it doesn't want to shoot out in a direction where it's covered over by another branch.

Speaker 40 It needs to get its own sunlight. So if the branches have to grow, I mean, natural selection, evolution will have disfavored the trees that don't follow this principle.

Speaker 40 That may have something to do with it. I'm not giving you a clear explanation because I don't honestly know.

Speaker 35 This is helpful. And then, like,

Speaker 65 maybe the same thing holds true for the poetry, where people are trying to create new

Speaker 65 newness. You're trying to make,

Speaker 35 I don't know, create space in a sense.

Speaker 40 Yes. You're trying to create novelty subject to constraints.

Speaker 40 Right. Right? And you could say novelty subject to constraints is art.

Speaker 40 Like growth in creativity subject to constraints. That's that's what art is, right?

Speaker 16 Hmm.

Speaker 21 Yeah.

Speaker 40 Anyway.

Speaker 40 Huh.

Speaker 14 So what do you make of all that?

Speaker 50 I guess, I don't know.

Speaker 78 It sort of makes me see the plants as

Speaker 16 a little bit more artistic than it did before.

Speaker 16 And

Speaker 36 the poetry as

Speaker 36 like

Speaker 35 a little bit more

Speaker 35 from nature.

Speaker 33 That gives me goosebumps.

Speaker 30 That's really cool.

Speaker 50 Yeah.

Speaker 18 You're also missing the other takeaway here, which is that

Speaker 18 Fibonacci didn't discover the Fibonacci sequence, and that's not even his real name.

Speaker 29 He wasn't even named Fibonacci.

Speaker 76 That is the point.

Speaker 75 Let's bring it back down to Earth and focus on what really matters.

Speaker 20 What really matters is that he's not a family.

Speaker 28 Just that Fibonacci.

Speaker 62 is not who we thought he was.

Speaker 33 Well, thank you, Pat. That was beautiful.
And we will be back in just a moment with one last girl story.

Speaker 18 Of planetary scale and import.

Speaker 33 And the little humans trying to control it.

Speaker 30 Stick with us.

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Speaker 73 It's 1972. A young British family is attempting to sail around the world when disaster strikes.
Their boat is hit by killer whales and it sinks in seconds.

Speaker 73 All they have left is a life raft and each other. This is the true story of the Robertson family and their fight to survive, hosted by me, Becky Milligan.

Speaker 73 Listen to Adrift, an Apple original podcast produced by Blanchard House. Follow and listen on Apple podcasts.

Speaker 25 Lulu. Lattev.

Speaker 33 We are back. Okay, so.

Speaker 48 um with one more story of growth from producers Annie McEwen.

Speaker 25 Uh I've just detangled my headphones and Simon Adler.

Speaker 69 But go on, go on.

Speaker 33 All right, let us begin.

Speaker 33 All right. So I think like

Speaker 33 most people, I thought for the longest time that human population was growing really fast.

Speaker 82 We already have between three and seven times more people than we can permanently support.

Speaker 33 Maybe exponentially.

Speaker 82 The growth rate is just incredible.

Speaker 33 You know, people were popping kids out and blah, blah, blah.

Speaker 82 We are destroying our fossil fuels. We are dispersing our mineral resources.

Speaker 33 And that this was like a really big

Speaker 15 problem.

Speaker 33 We're freaked.

Speaker 24 Yeah. A ball of flesh expanding at the speed of light, I think.

Speaker 21 A ball of flesh expanding at the speed of light.

Speaker 16 Oh, God.

Speaker 33 This is Philip Cohen.

Speaker 24 I'm a professor of sociology at the University of Maryland.

Speaker 33 And I called him up to talk about this fear. It's one that I really took deep into my soul at some point in my life.
And he told me that like, yes, this was a real concern starting around the 1950s.

Speaker 24 Population did start increasing exponentially, you know, 2 billion, 4 billion, 8 billion.

Speaker 30 Population bomb kind of thing.

Speaker 33 Yes, yeah, yeah, yeah. But that by the time I had even started worrying about it, by the 90s, really, it was no longer a problem.

Speaker 37 Right.

Speaker 24 You know, it's obviously a long, complicated story, and it's different around the world.

Speaker 24 But with better health care, better contraception, and access to education, a lot of women started having fewer children.

Speaker 33 Fewer kids meant slower growth, and as growth slowed, demographers predicted that population would just plateau.

Speaker 52 Yes.

Speaker 24 The idea was that the average woman was going to have two children, and that world population would hit a peak around 10 billion, around 2060 or so, and after that, be stable.

Speaker 33 And we would all live happily ever after.

Speaker 16 Oh, thank God. Yeah, it's great.

Speaker 83 Big ol' exhale for Annie McEwen on on the population front.

Speaker 44 That's right.

Speaker 33 But then,

Speaker 33 like 10 seconds after I learned about this plateau and felt great about it, I learned that that is not what's happening. Hmm.

Speaker 50 Well,

Speaker 24 it would be in Europe that panic first started.

Speaker 33 Because instead of like watching things come to settle at a peaceful plateau, demographers noticed that, especially in Europe, but also in other parts of the world.

Speaker 24 You know, South Korea, China, Japan.

Speaker 33 That this drop in birth rates.

Speaker 24 It accelerates.

Speaker 33 The fall accelerates.

Speaker 16 Exactly.

Speaker 33 Birth rates in a bunch of places were now dipping too low.

Speaker 33 Okay, so I've got the latest fertility rate information here in front of me. So like ask me, ask me a country and I'll tell you.
Oh, good. Okay, France, France, France.

Speaker 33 Okay, so remember, for us to keep replacing ourselves, the number to hit is 2.1. France is 1.8.
France is 1.8.

Speaker 49 Okay.

Speaker 16 Au revoir.

Speaker 55 Poland.

Speaker 58 Poland is 1.5.

Speaker 16 1.5. Wow.
Yeah.

Speaker 55 Mexico? Mexico.

Speaker 33 1.8.

Speaker 14 Cameroon.

Speaker 33 4.29.

Speaker 55 So they're above Republican.

Speaker 16 Oh, they're high. Yeah, they're high.
They're high. But they're falling.

Speaker 33 Like in the 80s, I think it was 6.7.

Speaker 31 Whoa.

Speaker 50 What about Ghana?

Speaker 33 3.5. But they also fell from over six.

Speaker 31 Oh, wow. Italy?

Speaker 33 Italy is 1.3. Italy's low.

Speaker 25 Italy's 1.3.

Speaker 27 Wow.

Speaker 31 Yeah.

Speaker 33 What are we?

Speaker 49 What's the U.S.?

Speaker 33 1.7. 1.7.
Yeah. Wow.
And where's it the lowest?

Speaker 83 The lowest are like Korea and Japan, which I think Korea is at like 0.6.

Speaker 15 No.

Speaker 33 0.6, 0.7.

Speaker 43 Yeah.

Speaker 25 Wow. That's so low.

Speaker 48 Wait, and Earth as a whole is what right now?

Speaker 33 It's 2.3. So we're just above total.
Yeah. And Philip says that this downward trend is going to continue.

Speaker 24 The world population is going to hit a peak around 10 billion, around 2060 or so. And after that, it will almost certainly start to taper downward.

Speaker 33 So we are on the verge of beginning to shrink.

Speaker 33 Really?

Speaker 33 That makes me so happy.

Speaker 49 Yes!

Speaker 33 In a couple hundred years, it's projected that the Earth's population will actually be about 6 billion.

Speaker 16 Wow!

Speaker 25 That far down. So less than now.

Speaker 33 Oh, yeah.

Speaker 84 We were going to roller coaster and we're like, we're coming at that. We're like,

Speaker 3 it's like the tucker, tuck it, tuck it on the roller coaster before the drop.

Speaker 58 Exactly.

Speaker 84 I am really pumped to hear that.

Speaker 19 Whoa. I don't know.

Speaker 51 I think I kind of like the plateau. The plateau sounds so nice because the stability, it's like you can, you know what to plan for.

Speaker 25 Like, you know what to do.

Speaker 33 But it's a stability of like un of a herding earth and like strapped resources.

Speaker 31 How about a little less

Speaker 33 to drive cars and share weeds?

Speaker 67 That's fair, but I don't know. There's something that sounds sad about less people.

Speaker 26 It's like the parties ended.

Speaker 17 No.

Speaker 48 Like it's like the parties.

Speaker 33 It's literally not sad. It's like, that's great.
The parties, there's still so many people. The club is popping.
Yes, the club is popping. Yeah.

Speaker 33 I think when I heard this, I was like, okay, great. I feel relieved.
The skin ball is not going to happen. But I guess the thing that I was most struck by is just

Speaker 33 while I was freaking out about humans exploding off the planet, eating everything, there was a whole other group of people freaking out about the exact opposite.

Speaker 16 Really?

Speaker 55 Hey, would they be worried?

Speaker 33 Well, you know, some of them are the billionaires.

Speaker 85 You know, if we don't make enough people to at least sustain our numbers, perhaps increase a little bit, then civilization is going to crumble.

Speaker 33 Who are just like, let's grow, grow, grow so we can all make more money.

Speaker 85 I'd rather civilization win out with a bang than a whimper and adult diapers.

Speaker 33 But then there are like also regular economists, especially in like the Western capitalist economies, who say that the shrinking is a problem because our economy needs workers to just, you know, keep things chucking along.

Speaker 33 But I mean, what about immigration?

Speaker 3 Forget all the other reasons.

Speaker 33 Just looking at it from this economic viewpoint, I mean, people in the United States might not be having that many kids, but there are lots of people who would love to come and live here and therefore be workers in the economy.

Speaker 52 Yes.

Speaker 24 Anybody who says there's a population shortage or problem in any rich country has to at least answer the question of what about immigration?

Speaker 83 Like, were it not for immigration, the U.S.

Speaker 35 population would be falling right now.

Speaker 30 Really?

Speaker 33 Yes. Or it would be falling very soon.

Speaker 26 Which is so crazy that the

Speaker 26 administration in power right now, the whole thing is like, get people out, get people out.

Speaker 25 And it's like, yeah, we kind of need people right now.

Speaker 16 Yeah.

Speaker 33 And actually, when I spoke with another demographer on the phone, James Ramo, he told me that like all these countries that are, you know, really not immigrant friendly, in 50 years' time, they're going to be fighting to attract immigrants.

Speaker 14 Oh, I bet.

Speaker 34 I bet.

Speaker 33 But like, even with all these wealthy countries holding their doors wide open, that's only a temporary fix.

Speaker 24 That works for, you know, maybe 100 years or 50 years.

Speaker 33 Because by the year 2100, 97% of the world's countries will be below replacement levels.

Speaker 33 So this sort of decline in fertility is happening everywhere and it's happening more slowly in some countries than others, but it is happening.

Speaker 33 So, basically, in 70 years or so, most of the planet will be dipping. Yes.

Speaker 33 And like, I think talking about the economy, especially the economy in the future, it feels just very abstract.

Speaker 33 But for me, like, the whole thing started to get kind of unsettling when I called up another demographer.

Speaker 16 Hello?

Speaker 58 Oh, I hear them. Hello.

Speaker 33 This one named Leslie Root.

Speaker 53 I am assistant professor of research at the University of Colorado Boulder.

Speaker 33 Who told me that, like, fundamentally, this whole thing is a question of how will we care for each other.

Speaker 53 So, this is this is true of like any human society, right? That you have people who need to be supported and you have people who are capable of supporting.

Speaker 53 And people who need to be supported are the very young, right? Like, human children are pretty hopeless. Um, and like compared to other primates, you know, they can't do anything.

Speaker 16 Useless, yeah, exactly.

Speaker 53 Um,

Speaker 53 and and the elderly. And then, sort of the prime working years is when we are supposed to be able to produce more than we consume so that we can share it with other people.

Speaker 53 And so a big concern is that when you have lower fertility and imagine your population with like people flowing into and out of it, fewer people are flowing in and the people who are already in it are getting older and older.

Speaker 53 So you have what's called an aging population.

Speaker 33 So like in 200 years, when the population is down to 6 billion, that's going to be a very different 6 billion than the one we just experienced in the year 2000 because a lot of those people are going to be very old.

Speaker 33 And the worry is that, like, as society becomes more and more top heavy.

Speaker 53 What does that mean for our ability to support each other?

Speaker 33 Like, just super practically, you know, like, who are all the doctors going to be to take care of these old people? And who's going to staff the nursing homes?

Speaker 33 And like, who will grow the food to feed these old people?

Speaker 33 Like, you can, you can sort of see that, like, as the proportion of young to old people shifts more and more out of whack, you have on the backs of these few young people kind of the burden of everything.

Speaker 58 Unless

Speaker 33 a whole bunch of us right now

Speaker 33 start to breed like rabbits, which is what a bunch of governments around the world are trying to get their citizens to do.

Speaker 53 Putin has urged Russian women to have eight or more babies.

Speaker 33 Here's a bunch of stuff that countries have tried.

Speaker 33 Japan tried government-sponsored speed dating night.

Speaker 33 Russia, they're like, hey, if you have more than two kids, we'll give you $7,000.

Speaker 53 Four times the average monthly wage.

Speaker 33 Taiwan, there was a presidential candidate in 2023 who was like, hey, the gift of yet another fairy child. Everyone who has a baby should get a free pet as well.

Speaker 16 A free pet?

Speaker 19 That's like more, more worth.

Speaker 33 There's also things like Sweden has these like amazing parental leave policies.

Speaker 13 480 days.

Speaker 33 Germany's got free daycare.

Speaker 21 That's money.

Speaker 33 And of course, there have also been some darker attempts to control, like in the US and North Korea where abortion has been banned

Speaker 49 but the crazy thing is that like carrot or stick

Speaker 83 none of this has worked none of it has worked yeah and the one thing I'll add to that is like with with few exceptions and the exceptions are sort of explainable away no country that has dipped below replacement rate has ever come back gone back above wow

Speaker 33 interesting right there really is no success story out there um nobody has shown how you can turn this around huh that's wild I mean do people have any idea why not I don't know I think I think it's because it's just really hard to answer the question why does someone choose to have a kid or not yeah there's a lot of like casting about for explanations of what exactly drives lower fertility there there are going to be a hundred reasons big and small why someone becomes a parent or not you know we we meet a partner or we don't, and our partner has the same preferences that we do, or they don't.

Speaker 33 We can find affordable housing, or we can't. We have access to great health care or we don't.

Speaker 53 We get a good job with flexible hours or we don't. We live near family who can babysit the kids or we don't.

Speaker 33 You know, for every one person, the decision is going to be this like really complicated mess of reasons and circumstances.

Speaker 33 And if you zoom out from there to the national or like the global level, looking down and trying to understand this is just total chaos.

Speaker 50 Hmm.

Speaker 34 Right.

Speaker 46 You're not going to solve the mystery of why.

Speaker 46 And basically, there's nothing you can do about it.

Speaker 46 So, what does this look like? You know, like, what does it look like when a society stops having children?

Speaker 58 This is Gideon Lewis Kraus.

Speaker 46 I'm a staff writer at the New Yorker.

Speaker 33 He recently wrote an essay about declining population called The End of Children.

Speaker 33 And as he was starting to report the piece, he noticed that like there were all these articles in Western media about South Korea.

Speaker 46 Obviously, South Korea with the lowest fertility rate in the world comes up all the time in all of these columns.

Speaker 46 And I noticed that everybody invoked South Korea, but it didn't seem like anyone had gone there. And I thought, like, it would be interesting to hear from some South Koreans about this.

Speaker 33 South Korea is a country that has more deaths than births every year. And it's not an easy country to immigrate to.
So its population is getting older and smaller.

Speaker 33 And so it's sort of seen as almost like this bellwether for where the rest of us are headed.

Speaker 46 And so I got there and

Speaker 46 I got into the center of Seoul and I went to the subway at rush hour and you saw no children anywhere.

Speaker 46 But at first I thought like, oh, well, you know, in New York, like, would I take my kids on the rush hour subway? Like, probably not.

Speaker 46 But then pretty immediately, like, you really just don't, you know, you don't see playgrounds or like the handful of playgrounds that i saw were completely empty at any time of day and you just don't see a lot of children and there were these no kids zones everywhere there were signs on restaurants and other establishments that said no kids here and i mean so much of it is about a rapid shift in cultural norms about kids so in the in fact i met with this young economics reporter who writes about this for a living and she was in her late 20s or early 30s and she said like i understand all of this stuff on on a deep economic level but when I write about it, I think, like, well, what would change my mind?

Speaker 46 And the answer is nothing. There's nothing that would make me want to have kids because it's the norm to not want to have kids.

Speaker 33 Gideon eventually made his way out to some of the more rural areas of the country where it's projected that about 2,000 schools are going to be closing in the next 10 years.

Speaker 46 And so I wanted to go visit one of these schools. So I went to one in the far south.
And this school, I think as max, it had about 1,300 students.

Speaker 60 Now it has five.

Speaker 83 It had

Speaker 83 five students.

Speaker 46 Five students, yeah.

Speaker 37 What grades?

Speaker 46 It had three first graders and two sixth graders.

Speaker 46 And when I was talking to the sixth grade teacher, I said to him, like, so you have two kids, like, do they get along? And he like looked at me like I was a complete idiot.

Speaker 21 And he was like, what do you mean?

Speaker 46 Like, do they get along? Like, they don't know anyone else. They've been in school together since they started school.
Like, the other child is like the only other child they know.

Speaker 55 What was it like walking through this school? Like, what did it look like?

Speaker 46 Well, there, you know, there's a feeling of great dignity and resignation about this stuff.

Speaker 46 So, this, you know, the outside of the school had been freshly painted, and the inside was bright and totally broom swept and spotless. And everything was in perfect order, except it was empty.

Speaker 46 And, like, there was no heat on in the hallways.

Speaker 46 And almost all the classrooms were dark. And some of the classrooms had photos of the last group of kids that occupied that classroom.

Speaker 46 And, like, the classroom was dark and just hadn't been open in a couple of years. And

Speaker 46 the cafeteria had like a little proscenium stage with a curtain, and clearly they had had like school plays there and stuff.

Speaker 46 And like, you know, you probably could have seated 300 people in this cafeteria.

Speaker 46 So it just felt like everyone had evaporated. Like there was no sense of decay.
It just felt like everyone had evaporated.

Speaker 33 Right. It does feel like children are disappearing.

Speaker 34 Yeah.

Speaker 16 And

Speaker 46 something like 200 nursery schools have been converted into retirement homes because there's like a radical dearth of retirement homes.

Speaker 46 And you can see that some of these nursery schools that have been turned into retirement homes, they've kept the same directors and they had kept the same like rubberized play floors for for the old people.

Speaker 46 And they even had, actually, my fact checker, Emily, found this.

Speaker 46 When she talked to them, she was like, Not only do we have the same rubberized play floors, we have the same crayons that, like, the kids used to use the crayons, and now we just like the seniors use the crayons.

Speaker 16 There's something really dark about that. Yeah.
Yeah. Yeah.

Speaker 25 The bell curve of life.

Speaker 25 But this is our projection.

Speaker 14 Yeah.

Speaker 20 We've already in this very story been wrong twice about projections.

Speaker 3 We thought, oh my God, it was going to be a population bomb explosion, too many people. Then we were like, oh, it's going to level out so nicely, perfectly.

Speaker 25 That didn't happen.

Speaker 3 How do we know that these projections are worth anything?

Speaker 16 Yeah. Yes.
That's a great question.

Speaker 33 That is a great question.

Speaker 33 I think that

Speaker 33 we just don't know. We just don't know what's going to happen next.
But what we're heading towards is like really unprecedented.

Speaker 33 And there is no way to to like be like, oh, yeah, last time we, this happened. So we can project forward to the matter.
Right, right. And I do think that the last planet we were on.

Speaker 58 Yeah.

Speaker 33 And as fewer people have fewer kids, those fewer kids are going to have fewer kids. And this is just mathematically, it seems tricky to get out of that spiral.
However, we totally don't quite know.

Speaker 33 And I think that's very fair.

Speaker 33 What is very much agreed upon is that the population of the world is going to start declining. And that is a totally new thing for humanity.
And that is set to happen pretty soon.

Speaker 52 Yeah, yes, pretty soon.

Speaker 52 I hope to live to see it.

Speaker 33 It's just interesting to imagine being on the planet and sort of looking around and being like, this is the most people there might ever be alive at one time.

Speaker 24 At that moment, yeah.

Speaker 52 It's big.

Speaker 24 It's like, yes, it's like going to the moon or,

Speaker 24 you know, our first nuclear bomb. I mean,

Speaker 24 it's a big moment in human history when

Speaker 24 we turn that around. And for the first time, the global population is declining.
You know, feeling like you might never come back from it. Like

Speaker 24 you've changed direction.

Speaker 33 Yeah, it's a shift from growth to something else.

Speaker 33 Something new.

Speaker 30 Right, exactly.

Speaker 33 Producers Annie McEwen and Simon Adler.

Speaker 61 So that's the the end of the growth show,

Speaker 14 a story about shrinking.

Speaker 31 Yeah.

Speaker 33 Yeah, from a pumpkin that was kind of growing uncontrollably to a population that seems to be shrinking uncontrollably.

Speaker 15 Well, at least we're making room for more giant pumpkins.

Speaker 84 There's always that, the silver lining, the orange lining.

Speaker 33 That, I guess, is our show.

Speaker 6 This episode was reported and produced by Matt Kilty, Becca Becca Bressler, Pat Walters, Sindhun Yana Sumbanden, Annie McEwen, and Simon Adler, with additional reporting by Ray Mondo, and it was edited by Pat Walters.

Speaker 33 Mixing and sound design by Jeremy Bloom, fact-checking by Emily Krieger and Natalie Middleton, and special thanks to Ellie Tanaka, Keith Devlin, Devin Patel, Chris Golay, James Raymond, and Jessica Savage.

Speaker 43 I'm Lula Miller.

Speaker 14 And I'm Leftif Nasser.

Speaker 34 Thanks for listening.

Speaker 77 I'll see you soon.

Speaker 85 Hi, I'm Paolo Mara Biggs, and I'm calling from Nuuli, American Sahamoa.

Speaker 86 And here are the staff credits. Radiolab was created by Jad Abimrad and is edited by Soren Wheeler.

Speaker 85 Lulu Miller and Natap Nasser are our co-hosts.

Speaker 86 Dylan Keefe is our Director of Sound Design.

Speaker 85 Our staff includes Simon Adler, Jeremy Bloom, Becca Bressler, W.

Speaker 85 Harry Fortuna, David Gable, Maria Paz Gutierrez, Sindhu Namasamadam, Matt Teoti, Enin McEwen, Alex Neeson, Sara Kari, Sara Sandbach, Anissa Vitsa, Arianne Wack, Pat Walters, and Molly Webster.

Speaker 85 Our fact checkers are Diane Kelly, Emily Krieger, and Natalie Middleton.

Speaker 86 Bakatai, Telelaba, Maro.

Speaker 87 Hey, I'm Steph. I'm from Melbourne, Australia.

Speaker 87 Leadership support for Radiolab science programming is provided by the Gordon and Betty Moore Foundation, Science Sandbox, a Simons Foundation Initiative, and the John Templeton Foundation.

Speaker 87 Foundational support for Radiolab was provided by the Alfred P. Sloan Foundation.

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