Less Than Kilogram

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Speaker 1 Radiolab is supported by Apple TV. It's 1972.
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Speaker 1 Hey, it's Lot Diff. This is Radiolab.

Speaker 1 I'm thinking today in the aftermath of American Thanksgiving about all the people who got together with their families, sat down for a nice little meal, and then, oh, God, politics came up somehow, and they found there was just something they couldn't agree on.

Speaker 1 And you can't even reckon, like, how does this other person not even understand the basic facts of the situation?

Speaker 1 And so, if you're leaving this holiday feeling like you need something concrete, something apolitical, something objective in this moment,

Speaker 1 this episode is for you. It's an episode we originally broadcast in 2014 about a project to make something

Speaker 1 everlasting, something that everyone, everywhere, could agree to follow.

Speaker 1 And we actually have a kind of a dramatic update at the end. So stay tuned for that.

Speaker 1 Here you are, less than kilogram.

Speaker 5 Wait, you're listening.

Speaker 4 You're listening

Speaker 4 to Radio Lab.

Speaker 4 Radio Lab. From

Speaker 6 W-N-Y-C.

Speaker 7 Re-wine.

Speaker 8 Hey, I'm Jad Abum Ron.

Speaker 9 I'm Robert Krillwich.

Speaker 1 This is Radio Lab, the podcast.

Speaker 10 And this.

Speaker 11 I actually brought a list. Okay,

Speaker 14 why don't you share with me your list?

Speaker 5 Where is this thing?

Speaker 15 This is Andrew Morantz.

Speaker 16 He's a writer and editor at the New Yorker magazine.

Speaker 10 Oh, I might have gotten lost.

Speaker 12 Who occasionally pops onto our show?

Speaker 17 Maybe you were mugged.

Speaker 11 Maybe.

Speaker 10 Ah, here it is.

Speaker 16 And he recently got obsessed with a

Speaker 17 list of measurements.

Speaker 13 Base units, they're called.

Speaker 6 They're SI base units, the System Internationale.

Speaker 20 So let me do it this way. Have you ever wondered how long an inch is?

Speaker 17 Exactly how long?

Speaker 8 I know. I just look at a ruler.

Speaker 17 Well, but how do you know that your ruler and my ruler do have the same amount of inch space?

Speaker 15 Or that someone in China, that their inches are inches, your inch is my inch.

Speaker 8 I haven't really thought about it, but I just assume that there's like a master inch somewhere.

Speaker 4 Bien too.

Speaker 21 I say it in French for a reason, which you'll feel in a moment.

Speaker 18 That is what was on this list that Andrew was looking at.

Speaker 23 It's a list of standard measures for everything we have around how big something is, how far something is, how hot something is, it's all on this list.

Speaker 6 Okay, so when you go down the list of the Systeme Internationale de Unites, here's what you get.

Speaker 10 A meter.

Speaker 6 A meter is a fraction of a second of the distance traveled by light in a vacuum.

Speaker 10 Okay.

Speaker 4 What?

Speaker 6 A second is how much radiation corresponds to the transition between two hyperfine levels of the ground state of the cesium-133 atom. That's the definition of a second?

Speaker 9 How many times does a particular atom jiggle? Yeah.

Speaker 4 Wow.

Speaker 6 An ampere, which measures electric current?

Speaker 4 You know, an amp.

Speaker 6 Is a constant current, which, if maintained in two straight parallel conductors of infinite length, would produce between these conductors a force equal to two times ten to the negative seventh newtons per meter of length.

Speaker 6 I have no idea what that means.

Speaker 25 See, that's the thing. If you look at the actual definitions of any of these things, amp, meter, second, whatever, you go...

Speaker 18 But there is one standard on the list that is unique for its simplicity.

Speaker 6 The definition of the standard unit unit of measurement that is a kilogram is no math, no numbers.

Speaker 26 It is a

Speaker 4 thing.

Speaker 24 A particular thing?

Speaker 6 A plum-sized

Speaker 11 thing.

Speaker 18 It is the only thing we use to measure things.

Speaker 13 It's the last one standing, the only physical standard left.

Speaker 27 Why is it the last?

Speaker 8 And why were there is it what?

Speaker 24 Wait, what?

Speaker 9 Let me just take you back to the beginning of the story.

Speaker 1 Like, I must admit that I expected this story to be a lot more boring than I found. It's like an epic story.

Speaker 18 That is Latif Nasser, science historian, regular on our show.

Speaker 13 And he says, if you go all the way back to the very first farmers back in Mesopotamia.

Speaker 1 All of the earliest measurements were super intuitive. And he says a lot of them came from the body.

Speaker 16 As in, that bunny is coming close to the net.

Speaker 1 How close, dad? Two hands.

Speaker 1 But it's not just like, because we think of like hands and feet, but it it was also there so many other kinds of measurements like you would say oh something is as far as you know my voice can carry or that Something is as far as I can see sitting on the top of a camel

Speaker 1 or something is as far as I can throw a stone

Speaker 22 So that would mean like say okay I'm going to build a farm here and I'm going to do it three thrower rocks across?

Speaker 1 Yeah, yeah. The way I read about it was like travelers.
Like if you're a Saharan traveler, you know, and you need to know where the next watering hole is,

Speaker 1 that's kind of a life and death measurement. Yeah.
They would say it's, you know, three throw a rocks away or it's ten throw rocks away.

Speaker 9 But, you know, there might be some built-in uncertainty there because if you ask Achilles,

Speaker 18 it could be two throw rocks away, but if you ask me, it would be like 78.

Speaker 1 You have nailed exactly the problem with the throw-a-rock system.

Speaker 23 And these problems kind of came to a head in the 1700s.

Speaker 1 It's the eve of the French Revolution.

Speaker 20 In a little town called Paris.

Speaker 1 It's a pretty cosmopolitan place, which means that people are coming from different places and they all have their own measures. Approximately 250,000 different units of measurement in regular use.

Speaker 24 250,000.

Speaker 1 Every commodity has its own measure, so you have grain, wine, oil, salt, hay, coal, wood, fabric, everything.

Speaker 1 And it's extraordinarily confusing.

Speaker 13 Not to mention it's extraordinarily bad for trade.

Speaker 18 So if I came to you and I said, Monsieur, I have a bit of cloth,

Speaker 25 you would say, How much cloth you got?

Speaker 12 And I'd say, I have

Speaker 28 two yards.

Speaker 18 And you'd say, what's a yard?

Speaker 13 I said, it's this much.

Speaker 29 And the other guy would say, no, no, it's this much.

Speaker 20 And I was like, no, no, it's this much.

Speaker 4 And I'd go, no, no, it's this much.

Speaker 25 And you can see that it's... Frustrating.
It was frustrating. Yeah.

Speaker 13 And making matters worse.

Speaker 1 In the 1780s, there was a famine. So there was a shortage of grain, and people were hungry and people were angry,

Speaker 1 which I am going to call that they were hangry.

Speaker 11 They were hangry.

Speaker 1 They were very hangry. So the bakers at the time, they knew that if they raised the price of bread, like an angry mob would basically come and kill them.

Speaker 16 But they also knew that with no absolute standard, there was no way to be sure that what you were getting is what you were getting.

Speaker 1 And so what they started doing was they started just lightening their bread loaves by just a little.

Speaker 1 So as the famine got worse, people would be waiting in longer and longer lines to pay the same amount of money for smaller and smaller loaves. So, they were getting hangrier and hangrier.

Speaker 1 And so, one of the things that people are like crying out for is that they want standardized weights and measures. If I go to the bakery and I buy a loaf of bread, I want a whole loaf of bread.

Speaker 1 Don't short me on this. This is serious.

Speaker 14 Well, you know what happens next.

Speaker 1 The Bastille is stormed, and the king is under house arrest and then under the

Speaker 9 guillotine.

Speaker 13 And as soon as the revolutionary government takes over, they say, all right.

Speaker 1 Okay, this is one of our first priorities. We are going to make a new standard.

Speaker 18 But not based on something arbitrary like a king.

Speaker 1 This is the Enlightenment. Why don't we draw on some kind of totally different authority? The authority of nature.

Speaker 17 Of nature. Of nature.

Speaker 16 So, long story short, they took the circumference of the Earth.

Speaker 9 They took a quarter of that circumference, divided that by 10 million, and they got the meter.

Speaker 16 The meter they then divided by 10, cubed it, filled the cube with water, took the mass of the water, minted a cylinder of metal with that mass, and voila, they created the world's first kilogram.

Speaker 1 The idea of this was if we make this thing that is so beautiful and perfect and everybody can see it that way, then not only will France use it, but the whole world will use it.

Speaker 1 Then goods and ideas can be exchanged everywhere by all people and it will be beautiful.

Speaker 11 Exactly.

Speaker 1 They wanted something that would be eternal and unchanging for everybody, for all time.

Speaker 13 So now I guess you want to see it, no?

Speaker 4 Yeah. Okay.

Speaker 30 Okay, so it's in here.

Speaker 13 We ended up visiting the National Institute of Standards and Technology in Maryland.

Speaker 5 And this is where we'll be going in, but we're going to go in for this guy. Patrick Abbott, physicist, was our guide.

Speaker 22 They took us three stories down into the bedrock of the state of Maryland because they want things down here to be totally still.

Speaker 12 We've just gone through one double door.

Speaker 29 Here comes another double door.

Speaker 20 Then we stepped into this vault of a room and there it was.

Speaker 15 But what we're looking at then is a glass jar with a little handle on top and then inside that is another glass jar with a little handle on top and inside that is the thing.

Speaker 4 The thing.

Speaker 24 It's kind of

Speaker 24 gorgeous, really.

Speaker 29 The shiniest little cylinder you've ever seen.

Speaker 24 Very small, and it looks very clean.

Speaker 10 Doesn't it too?

Speaker 6 Yeah, it's almost hard to tell where the Russian doll glass jar stops because it's so reflective.

Speaker 31 This might be a crazy question, but can we hold a kilogram?

Speaker 8 That's our producer, Lindlevi.

Speaker 27 No.

Speaker 31 I'm just curious to know what it feels like. We've been talking about it so much.

Speaker 26 They are very careful with the kilogram.

Speaker 20 And this isn't even really the real one. The original of the original of the original of the original.

Speaker 18 Le Grand Car, as they call it, lives in a basement in France.

Speaker 17 You can't get anywhere near that one.

Speaker 12 I could.

Speaker 8 No, you couldn't. I could get all Tom Cruise on that.
You'd die trying.

Speaker 11 Here's how it works.

Speaker 27 The international prototype is Big Gahoon.

Speaker 16 Now, that's the one used to calibrate six identical platinum cylinders.

Speaker 27 What they call witnesses. Or tamois in French.

Speaker 16 Those witnesses are then used to calibrate another set of cylinders which are then used to calibrate the U.S. standards which is what we saw and that one is used to calibrate all kinds of things.

Speaker 18 The weight of your lemons, the scale in your bathroom.

Speaker 31 Green team you lost 34 pounds.

Speaker 32 Every time somebody loses a pound on that TV show Biggest Loser.

Speaker 31 5.87%.

Speaker 27 You can actually trace that like a bloodline if you will or an unbroken chain back to the international prototype kilogram.

Speaker 14 to a single object in a basement in france of the holy of holies that is the kilogram but you're telling me that when something is weighed in the world often it goes all the way back to this one hunk of metal that's what i'm saying which was why the next part of the story is so uh disconcerting what happened in 1989 is that according to andrew the folks who take care of the official kilogram the big k they took it out of its jars they put it in a steam bath

Speaker 27 hit it with the steam that rinses everything.

Speaker 6 Wait for it to dry.

Speaker 17 Then they commence a ceremonial weighing. Right.

Speaker 21 But how do you weigh the thing that is the standard of weight?

Speaker 6 Well, you weigh it against the copies.

Speaker 18 Like the U.S. copy, for example.
So they get one of those and they put it on one side of the scale and they put the grand qu on the other.

Speaker 17 And

Speaker 10 the IPK, the le grand cas, the one,

Speaker 1 is light.

Speaker 4 What?

Speaker 2 It's light.

Speaker 14 It doesn't.

Speaker 14 How many, how many, how much lighter is it than its sisters?

Speaker 6 Roughly the mass of a grain of sugar.

Speaker 2 Whoa. Yeah.

Speaker 13 Is that gigantic? It's measurable.

Speaker 8 Wait, how do they know that it was light and not that the other ones were heavier?

Speaker 6 Right. Well, they didn't.
So they used the second sister copy.

Speaker 13 Still light.

Speaker 6 And the third sister copy.

Speaker 13 Still light.

Speaker 6 And the fourth and fifth and sixth.

Speaker 32 In comes the man from Germany. Light.
In comes the man from Canada. Light.
In comes the man from Spain. Light.

Speaker 17 Which led them to the troubling possibility that the international standard for weight was losing weight.

Speaker 27 Well, we think that. We think the big guy's the problem.

Speaker 6 As far as how it lost that weight, really no one knows.

Speaker 14 One possibility is it got cleaned too much and maybe some of it got scraped away.

Speaker 6 Although it's disputed whether cleaning it more would make it lose weight or gain weight. The other theory is outgassing.

Speaker 14 Like maybe a little hydrogen is seeping out of the metal.

Speaker 6 And then there was one thing I read that said, foul play cannot be ruled out.

Speaker 25 Well, see, I was thinking, maybe the Taliban.

Speaker 13 What's clear is we may have a slightly trippy situation here.

Speaker 6 We got a hunger metal losing weight, and yet because it is the standard, it still weighs exactly a kilogram. Right?

Speaker 6 If the definition of a kilogram is the mass of the international prototype kilogram, whatever happens when you put that thing on the scale, that's a kilogram.

Speaker 18 You can't do that.

Speaker 6 And then everything else in the world is wrong.

Speaker 10 No, you can't do that.

Speaker 6 It's like that doesn't sit right. That's like something that like the North Korean government would do.

Speaker 10 Just be like, no more cash.

Speaker 6 Like that. We can't just go around capriciously doing stuff like that.

Speaker 8 All right. So if the standard of weight is, as you're saying, losing weight, so how do you fix that?

Speaker 1 An answer to that question after the break.

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Speaker 35 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 35 All they have left is a life raft and each other.

Speaker 35 This is the true story of the Robertson family and their fight to survive, hosted by me, Becky Milligan. Listen to Adrift, Adrift, an Apple original podcast produced by Blanchard House.

Speaker 35 Follow and listen on Apple podcasts.

Speaker 1 Hey, I'm Lent Dev Nasser. You're listening to Radio Lab.

Speaker 1 Before the break, we learned that the international standard for a kilogram, which is a tiny platinum cylinder, is ever so slowly losing weight.

Speaker 1 A problem which our emeritus host, Robert Krulwich, and New Yorker writer Andrew Morantz went to Maryland to investigate.

Speaker 6 Well, I'm getting zero cell phone reception down here.

Speaker 10 That means we're really deep.

Speaker 19 When we were down in that underground room in Maryland, we met a guy who has some thoughts about this.

Speaker 5 Oh, there he is.

Speaker 13 Okay. His name's John Pratt.

Speaker 30 I'm the leader of the Fundamental Electrical Measurements Group at the National Institute of Standards and Technology.

Speaker 5 Hi, John.

Speaker 22 John walked us through even more high-security doors, and then we walked into this.

Speaker 10 Oh, my God.

Speaker 28 Amazing room.

Speaker 31 It's big.

Speaker 18 It is big. About three stories tall.

Speaker 4 Yep.

Speaker 18 And it's made of...

Speaker 4 It's like a silver room.

Speaker 22 It has a silver gray floor. It has silver shiny walls.

Speaker 16 And your hair is on the silvery side.

Speaker 30 Very much so.

Speaker 24 You probably wouldn't be allowed in here if you were a redhead.

Speaker 4 No.

Speaker 20 I don't even know how to describe it.

Speaker 23 It looks like a wheel turned on its side.

Speaker 6 The thing itself. looked sort of just like

Speaker 6 a massive round metal cauldron or like a big metal pot but then there are all these weird little gizmos and parts and then all these coiled up wires and it's just a stunning machine but it's all just for the benefit of the one

Speaker 13 the one measure one kilogram yep because inside that giant cauldron there is an extremely extremely sensitive balance

Speaker 30 an equal arm balance which is basically like a seesaw or a teeter-totter and usually you would set that up so that you would literally put kid on one side of the teeter teeter-totter, kid on the other side of the teeter-totter.

Speaker 17 Now, you've been in a playground, so you know how this goes. But what they've done here is on one side of the teeter-totter, they've got the kilogram, like the ground gay.
That's kid number one.

Speaker 5 On the other side, instead of another kilogram or kid two, we'll have a highly variable magnet.

Speaker 4 Now, here's the thing.

Speaker 18 The magnet won't be touching that side of the scale.

Speaker 28 It'll be exerting a force, an invisible force on that side.

Speaker 30 It'll produce a force, and we could use that to hold the balance still.

Speaker 18 And the force it takes to hold up the balance, that of course is the same as the weight of the gong ka sitting on the other side.

Speaker 13 And if you can convert that force into a number that everybody agrees to, voila!

Speaker 9 You have just redefined the kilogram.

Speaker 18 You have wrenched it from the world of things, and it's become attached to the fundamental forces of the universe.

Speaker 30 Yep, you've grasped the gist of it.

Speaker 30 You want to see that happen?

Speaker 30 Right now, I can show you this with our Lego version of of the WAD balance. If I can fire it up.

Speaker 24 Lego?

Speaker 10 Lego one?

Speaker 9 Well, see, the big one was being tested or something, so they took us over to look at the little one.

Speaker 28 Okay, so we have a little scale and everything.

Speaker 30 You can see I just disturbed the balance, and it's you know, jiggling around a little.

Speaker 5 It's free-floating.

Speaker 14 Okay, so you're now going with your tweezers, and you're plucking a itty-bitty

Speaker 5 mass.

Speaker 11 He puts this tiny little thimble thing on the balance, and now it's going to, he says, levitate.

Speaker 7 Now it's it prompts me mass on mass on yeah i'm gonna put the mass on he pushes a button all right

Speaker 4 and

Speaker 6 wait but when do we see the levitation that was it i didn't i missed it do it again

Speaker 4 it was floating it is floating sitting on the balance okay that's not floating that is floating no way does it fall to earth

Speaker 16 that's a different idea

Speaker 25 levitation No, the truth is that once I finally figured out what this guy was doing, it was actually sort of cool.

Speaker 4 He had taken a little metal weight.

Speaker 13 He put it on one side of the scale.

Speaker 18 And on the other side of the scale, it was just empty.

Speaker 26 But yet, the thing didn't tip over because the empty side actually had a magnetic force equivalent to the metal holding it just perfectly still.

Speaker 8 So if they're able to do that, does that mean that the Grand K's reign is done?

Speaker 23 Not yet.

Speaker 24 No, because first of all, you have to get straight with a lot of math.

Speaker 30 MC squared equals H nu.

Speaker 18 work backwards you got to divide by e and then by m measure the b field whoo let's go and then you get your amperes and your watts and your planck's constant classical little bohr model of atoms and stuff anyway it is actually way more complicated this whole thing than i frankly will ever understand but here's where we are at

Speaker 16 You got all these different teams around the world. You got John's team in Maryland with his seesaw.
You got another lab, actually a couple of them that have their seesaws.

Speaker 14 You got a third lab that's literally counting the atoms.

Speaker 16 They're all doing experiments, comparing numbers, trying to get the numbers to agree so that by whatever route, everybody agrees on exactly what a kilogram is.

Speaker 9 Right now, they're close.

Speaker 18 They're in agreement out to about six decimal places, and that's not good enough.

Speaker 16 They want the numbers to agree out to eight decimal places.

Speaker 18 But if they can do that,

Speaker 4 then

Speaker 13 and only then will the grand que be no more.

Speaker 30 Yeah.

Speaker 16 Because instead of defining the kilogram as whatever is equal to the grand que,

Speaker 19 now you have a new definition.

Speaker 30 The new definition of the kilogram. The kilogram is the SI unit of mass.
Its magnitude is set by fixing the numerical value of the Planck constant to be equal to exactly 6.626069.

Speaker 30 And we have x's because we haven't all agreed what the final

Speaker 30 missing decimal places times 10 to the minus 34 when it's expressed in the unit for actions joule seconds, which is

Speaker 30 a meter squared kilogram per second.

Speaker 6 Phew, that'll be such a simpler definition.

Speaker 7 Oh, yeah.

Speaker 5 No, you've...

Speaker 8 And what will happen to the Grand Cai when the new definition goes into effect?

Speaker 33 Well, so this is the sad part.

Speaker 33 Looks like a church.

Speaker 36 We will see after the end.

Speaker 14 The Grand Cai may eventually end up in a place like this.

Speaker 14 That's a big shield.

Speaker 18 Where so many standards have gone to die. This is the Musée des Ars et Métiers April in Paris.

Speaker 36 So this is the beginning?

Speaker 18 Joel Fasseau is our tour guide.

Speaker 4 Yeah, what is this?

Speaker 22 He showed us the original meter.

Speaker 13 Wow, some early thermometers.

Speaker 5 There's one funny object here.

Speaker 22 In one room, he showed us the original.

Speaker 20 I think it was the Parisian meter. So in Paris, this was the infallible, the absolute standard.

Speaker 5 From 1801, I think.

Speaker 33 It's in a wooden box with a velvet packing, and it's got silk ribbons at either end.

Speaker 33 And it's just a very beautiful-looking silver rod.

Speaker 8 Ah, to imagine, like, the thing, the grand thing, being in this place. It's sort of like seeing the Pope in shorts or something.

Speaker 4 It makes me a little

Speaker 8 uncomfortable.

Speaker 1 So, while we were over here singing the praises of this object, how beautiful it is to have something real you can hold in your hands, there's a group of people for whom the kilogram situation was unacceptable.

Speaker 37 This is scandalous.

Speaker 1 For example, Bill Phillips here from the National Institute of Standards and Technology. He's speaking to a big gathering of people who care about this stuff.

Speaker 37 If this were the real kilogram that I was holding in my hands, the fingerprints that have been put onto this kilogram would increase the mass, but of course it can't increase the mass because this is by definition a kilogram.

Speaker 5 That means all of you would lose weight.

Speaker 1 For the people in this room, the fact that we in the 21st century are basing our most finely tuned measurements on a hunk of metal cast in 1889?

Speaker 27 Now, that's a situation that is clearly intolerable.

Speaker 1 After years of work, researchers figured out that new definition they were looking for. In 2018, representatives gathered together in France

Speaker 1 and they voted to replace the physical kilogram with that abstract bit of math.

Speaker 5 South Africa.

Speaker 5 Yes.

Speaker 1 Alemain, Germany.

Speaker 5 Yes.

Speaker 5 Arabi Saudit, Saudi Arabia.

Speaker 36 Yes. Thank you.

Speaker 5 Argentine, Argentina.

Speaker 1 The physical kilogram was relegated to the dustbin of history.

Speaker 5 Australia, Australia.

Speaker 4 Autrice,

Speaker 36 Austria.

Speaker 36 Yes.

Speaker 4 Belgique, Belgium.

Speaker 1 Brazil, Brazil.

Speaker 1 Yes.

Speaker 2 Thank you.

Speaker 2 Bulgaria,

Speaker 2 Bulgaria.

Speaker 23 Special thanks to Ari Adland and Eric Earlmother.

Speaker 22 And also to Terry Quinn.

Speaker 9 We don't want to forget Richard Davis.

Speaker 4 And Hen Older, Bob Waters, Michael Paul, Michael Newman.

Speaker 20 And finally.

Speaker 8 Thank you to our math angel soprano.

Speaker 4 Melissa Hughes.

Speaker 4 It's very weird to say my own name.

Speaker 8 Also, big props to reporter Andrew Morantz, Latif Nasser, and our producer Lynn Levy.

Speaker 38 Hello, I'm Natalia, and I'm from New York City. And here are the staff's credits.
Radiolab was created by Jad Abimrod and is edited by Soren Wheeler.

Speaker 38 Lulu Miller and Lattev Nasser are our wonderful co-hosts. Dylan Keefe is our director of sound design.

Speaker 38 Our staff includes Simon Adler, Jeremy Bloom, Becca Bresler, W. Harry Fortuna, David Gable,

Speaker 38 Maria Fascutieras, Sindhu Nyanam Sambandan, Matt Kilty, Rebecca Lacks, Annie McEwen, Alex Neeson, Sara Kari, Sarah Sandback, Anissa Vitsa, Ariane Wack, Pat Walters, and Molly Webster.

Speaker 38 Our fact-checkers are Diane Kelly, Emily Krieger, and Natalie Middleton. Thanks for listening to Radio Lab.
Bye!

Speaker 39 Hi, my name is Michael Smith. I'm calling from Pennington, New Jersey.

Speaker 39 Leadership support for Radiolab science programming is provided by the Gordon and Betty Moore Foundation, Science Sandbox, Assiments Foundation Initiative, and the John Templeton Foundation.

Speaker 39 Foundational support for Radio Lab is provided by the Alfred P. Sloan Foundation.

Speaker 1 Radiolab is supported by Capital One. Banking with Capital One helps you keep more money in your wallet with no fees or minimums on checking accounts and no overdraft fees.

Speaker 1 Just ask the Capital One Bank guy. It's pretty much all he talks about in a good way.
He'd also tell you that Radio Lab is his favorite podcast too. Aw, really? Thanks, Capital One Bank Guy.

Speaker 1 What's in your wallet? Terms apply. See capital1.com/slash bank, capital One N-A, member, F-D-I-C.

Speaker 1 Radiolab is supported by the National Forest Foundation, a nonprofit transforming America's love of nature into action for our forests.

Speaker 1 Did you know that national forests provide clean drinking water to one in three Americans? And when forests struggle, so do we.

Speaker 1 The National Forest Foundation creates lasting impact by restoring forests and watersheds, strengthening wildfire resilience, and expanding recreation access for all.

Speaker 1 Last year, they planted 5.3 million trees and led over 300 projects to protect nature and communities nationwide. Learn more at nationalforests.org/slash radiolive.