Polymetalic Nodules Are Weird

What if one of the most valuable objects on Earth has been sitting untouched at the bottom of the ocean for 100 million years? In this Field Notes episode, Professor Hannah Fry brings Michael Stevens (VSauce) a strange metallic rock formed in the deepest parts of the Atlantic over millions of years. What begins with a bizarre Cold War CIA cover story involving Howard Hughes and a sunken Soviet submarine quickly turns into a journey through deep sea geology, natural “electric” rocks, and the environmental dilemma of mining the ocean floor for the rare metals used in electric car batteries. Plus: can you train yourself to become ambidextrous? are giraffes more vulnerable to lightning strikes than other animals? Does damp cold really feel colder than dry cold? And do humans actually sense wetness at all? ------------------- For more information about Cancer Research UK, their research, breakthroughs and how you can support them, visit ⁠⁠https://cancerresearchuk.org/restisscience⁠⁠ Cancer Research UK is a registered charity in England and Wales (1089464), Scotland (SC041666), the Isle of Man (1103) and Jersey (247). A company limited by guarantee. Registered company in England and Wales (4325234) and the Isle of Man (5713F). Registered address: 2 Redman Place, London, E20 1JQ. ------------------- Find The Rest Is Science all over the internet by ⁠⁠clicking here.⁠⁠ ------------------- Video Producers: Adam Thornton + Oli Oakley + Jack Meek Animator: Sam Benson Video & Social: Bex Tyrrell Assistant Producer: Lucy Lipscombe Producer: Simona Rata Senior Producer: Lauren Armstrong-Carter Head Of Digital: Samuel Oakley Exec Producer: Neil Fearn Learn more about your ad choices. Visit podcastchoices.com/adchoices

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

• 0:01Hannah Fry?

  Welcome to The Rest of Science. I'm Hannah Fry.

• 0:03Michael Stevens?

  And I'm Michael Stevens.

• 0:04Hannah Fry?

  And we're doing field notes today, which is where one of us brings a little object. My object starts with a story. Have you heard about that? That Howard Hughes, the eccentric billionaire?

• 0:13Michael Stevens?

  I've heard of him, yeah.

• 0:14Hannah Fry?

  You've heard of him? He comes up. You know, in the middle of the Cold War, he built this massive ship. Do you know this story?

• 0:22Michael Stevens?

  Like a ship that floated?

• 0:24Hannah Fry?

  A ship that floated.

• 0:25Michael Stevens?

  I know, I knew more about his airplanes.

• 0:26Hannah Fry?

  Okay, it's called the Glomar Explorer.

• 0:29Michael Stevens?

  Oh.

• 0:29Hannah Fry?

  And he did this big announcement to the whole world, and he said that he was gonna go out on the ocean, and he was gonna mine these worthless-looking black rocks at the bottom of the Pacific Ocean.

• 0:40Michael Stevens?

  For what? For iron?

• 0:42Hannah Fry?

  I mean...

• 0:43Michael Stevens?

  Nickel, gold?

• 0:44Hannah Fry?

  Whatever.

• 0:45Michael Stevens?

  For whatever?

• 0:45Hannah Fry?

  For whatever.

• 0:46Michael Stevens?

  Okay.

• 0:46Hannah Fry?

  Just about plausible enough to seem true.

• 0:48Michael Stevens?

  Yeah.

• 0:49Hannah Fry?

  It was actually this massive stunt that the CIA were doing, what he was actually doing. Do you know about this?

• 0:56Michael Stevens?

  Wait, I remember this story vaguely. Let me guess. What he was actually doing was? No, I don't. Tell me.

• 1:04Hannah Fry?

  He had nothing to do with it at all, really. He was just a cover. It wasn't his ship.

• 1:08Michael Stevens?

  The CIA was doing something.

• 1:10Hannah Fry?

  Yes, the CIA wanted to steal a sunken Soviet submarine.

• 1:16Michael Stevens?

  For its technology?

• 1:18Hannah Fry?

  Yeah, what they were doing on there. So they needed to send over this massive ship that was gonna go down to the bottom of the ocean, but they needed this cover story, and they were like, "Howard Hughes, and you know, this whole, like, oh yeah, rocks at the bottom of the ocean, lol."

• 1:32Michael Stevens?

  Yeah.

• 1:32Hannah Fry?

  And it worked. It was this really great piece of theatre.

• 1:43Hannah Fry?

  This episode is brought to you by Cancer Research UK.

• 1:46Michael Stevens?

  Here's something strange. Your DNA contains more ancient viral fragments than genes. The genes that build our cells make up only 2% of our DNA. And for years, that is what scientists focused on. They treated the rest, the ancient viruses and stuff, as junk.

• 2:06Hannah Fry?

  But now we know that that hidden majority, sometimes called... The dark genome influences how our biology works and how diseases like cancer behave.

• 2:17Michael Stevens?

  It's a reminder that progress rarely comes as a single breakthrough. It builds gradually. Cancer Research UK plays a central role in that progress, supporting decades of research into over 200 types of cancer, work that's helped double survival in the UK over the past 50 years.

• 2:36Hannah Fry?

  For more information about Cancer Research UK, their research breakthroughs and how you can support them, visit cancerresearchuk.org/the rest is science.

• 2:48Speaker 02

  Hi, this is Gary Lineker from Goalhangers, The Rest Is Football. This episode is brought to you by Wise. It's only when you start moving money between currencies that you really think about the exchange rate, the fee, and what might be hidden away in the small print. Whether you're living abroad, paying someone overseas, or just trying to manage your money across borders, you want a fair exchange rate, an easy transfer, and no surprises along the way. Wise keeps things simple. Wise is a smart way to move the currencies you need around the globe. It works in more than 160 countries and with over 40 currencies. Most transfers arrive instantly. Wise uses the mid-market exchange rate, like the one you see on Google, with no markups or hidden fees.

• 3:32Speaker 02

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• 4:29Speaker 03

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• 5:22Michael Stevens?

  Describe bottom of the ocean, like how deep?

• 5:25Hannah Fry?

  Oh, I'm talking bottom.

• 5:26Michael Stevens?

  Bottom.

• 5:27Hannah Fry?

  Bottom of the ocean.

• 5:28Michael Stevens?

  That's cool.

• 5:29Hannah Fry?

  Okay. Now, I have to tell you first, before I hand this to you. This is now, I think, one of my prized possessions, but I feel very guilty because somebody, I don't know who, sent this to me as a gift to my Cambridge office. Okay, and they had a really lovely letter in there, and there was a map from exactly where it was recovered, from what part of the ocean. And I can't find the letter anywhere. I can only find this.

• 5:54Michael Stevens?

  Do you remember if it was the Atlantic or the Pacific?

• 5:56Hannah Fry?

  It was the Atlantic. It was the Atlantic.

• 5:57Michael Stevens?

  Okay.

• 5:57Hannah Fry?

  So, anyway, whoever it was that sent me this, I'm really, really, really grateful. But this is what is known as a polymetallic nodule. It's in a little necklace thing. But you can pull it out if you want to. Okay.

• 6:06Michael Stevens?

  Oh.

• 6:07Hannah Fry?

  Right, I promise these are exciting, I promise.

• 6:09Michael Stevens?

  Okay, so it's inside a pendant on a string necklace, and the rock is black. It's about the size of a dye. And it is pitch black.

• 6:20Hannah Fry?

  Pull it out.

• 6:20Michael Stevens?

  I can pull it out? So, the pendant that it's inside is a wire that's coiled up into a big helix egg shape.

• 6:28Hannah Fry?

  Yeah.

• 6:28Michael Stevens?

  And it's like a copperish brass wire. So I'm gonna... How do I get it? I don't want to stretch this.

• 6:33Hannah Fry?

  Yeah, go on. You can stretch it.

• 6:34Michael Stevens?

  Okay, I'm gonna stretch it like I'm breaking an egg open and I'm gonna get the rock out. This is a great way to hold the rock because it won't fall out in normal use, but it does come out. Polymetalic nodule?

• 6:47Hannah Fry?

  Yes.

• 6:47Michael Stevens?

  So it has many different metals in it.

• 6:50Hannah Fry?

  Yes, and it feels really metallic.

• 6:51Michael Stevens?

  I gotta smell it. I don't know.

• 6:53Hannah Fry?

  Taste it.

• 6:53Michael Stevens?

  It's it's got it's got almost a chalky texture.

• 6:56Hannah Fry?

  It does, it does, it does.

• 6:57Michael Stevens?

  Can I lick it?

• 6:58Hannah Fry?

  Yeah, go on. What's gonna happen? Oh, no, wait. No, wait. No, joking.

• 7:02Michael Stevens?

  It's really dry.

• 7:03Hannah Fry?

  Is it?

• 7:04Michael Stevens?

  It's like drier than I would expect most rocks to be. I think it's it's a little porous. Is it volcanic?

• 7:09Hannah Fry?

  Uh, no, it is not volcanic.

• 7:12Michael Stevens?

  Okay, it's leaving dust on my fingers.

• 7:14Hannah Fry?

  Yeah, now I know.

• 7:15Michael Stevens?

  I got I'm gonna clean my tongue.

• 7:17Hannah Fry?

  I'm sorry.

• 7:18Michael Stevens?

  Because of what? There's probably lead in it.

• 7:20Hannah Fry?

  Oh, God.

• 7:21Michael Stevens?

  Hold on. Anyway, I did it for for you all.

• 7:25Hannah Fry?

  I hope there's not lead in it.

• 7:27Michael Stevens?

  It's not very dense.

• 7:29Hannah Fry?

  No.

• 7:29Michael Stevens?

  It it I'm making it sound like it's made out of polystyrene, but no, it's definitely a rock. I'm just gonna do a quick little mouthwash.

• 7:36Hannah Fry?

  You should at risk assess the idea of you licking a polymetallic nodule before you do it.

• 7:41Michael Stevens?

  Better me than like my child.

• 7:42Hannah Fry?

  I agree. Okay, I'm sure you'll be fine. Okay.

• 7:44Michael Stevens?

  I mean, surely the ocean washed it.

• 7:46Hannah Fry?

  Surely the ocean washed it. Okay, so right, the thing about these rocks, okay, they have the most unreal history, present and future, right, as three separate entities. So the way that they're created, these rock, I mean, why are you getting rocks at the bottom of the ocean? Surely it's all sand, right? It doesn't make any sense that you would have these rocks. But what happens is that a tiny bit of debris, right, and and it's things like a shark tooth or even longer ago, maybe a megalodon tooth or a little bit of a meteorite, something like that, floats down in the ocean and then settles in the the mud right at the bottom. And then they begin their life like this, but over millions and millions of years,

• 8:28Hannah Fry?

  think you've got all of these underwater volcanoes, so they're spewing out this very sort of metallic, rich uh debris all across the place. And over millions of years, manganese, nickel, cobalt, they they slowly come out of the seawater and end up bonding to this original seed, this original piece of debris. And this is, by the way, one of the slowest geological processes on the entire planet. They accumulate at about one millimeter every million years.

• 8:59Michael Stevens?

  Wow.

• 9:00Hannah Fry?

  Right, it's unbelievably slow. When you find them, they're roughly the size of a potato or a grapefruit, maybe.

• 9:07Michael Stevens?

  Really?

• 9:08Hannah Fry?

  And they're like these unbelievable pearls, you know, with this like incredibly interesting center and then extremely rich surrounding. So the fact that they're so old, you know, you have to, that was probably, the original seed for that was probably around the time of the dinosaurs.

• 9:25Michael Stevens?

  Yeah.

• 9:25Hannah Fry?

  Okay, that's what we're talking about. These grapefruits that are sitting at the bottom of the ocean that have been there since the time of the dinosaurs. But because they have so much metal in them, no lead, thankfully, we hope.

• 9:38Michael Stevens?

  Is that confirmed?

• 9:39Hannah Fry?

  Let's just check.

• 9:41Michael Stevens?

  Just pretend to check and then tell me that it's fine. What is this process of rock formation called?

• 9:45Hannah Fry?

  Okay, it's called hydrogenous precipitation. So the idea is that the top half of the nodule is kind of exposed to the seawater.

• 9:52Michael Stevens?

  Yeah.

• 9:53Hannah Fry?

  And then it just absorbs all of these dissolved metals as they flow past.

• 9:57Michael Stevens?

  And what, do they attract more?

• 9:59Hannah Fry?

  Yes.

• 10:00Michael Stevens?

  Oh, so it really is like a pearl forming in an oyster.

• 10:02Hannah Fry?

  It really is.

• 10:03Michael Stevens?

  Except the oyster is the entire ocean.

• 10:06Hannah Fry?

  Uh huh, exactly.

• 10:07Michael Stevens?

  Wow.

• 10:08Hannah Fry?

  So the other thing about these is that they essentially act as natural batteries because they've got these really tightly layered metallic isotopes.

• 10:14Michael Stevens?

  Yeah.

• 10:15Hannah Fry?

  They have this naturally occurring electrical charge in them. And when you get loads of them together, and you do, you get sort of, because of course a million years you get them, when you have thousands of them clustered together, the combined voltage can actually be like a volt, two volts or so, which means that you can split seawater into hydrogen and oxygen.

• 10:37Michael Stevens?

  Oh, yeah.

• 10:38Hannah Fry?

  And it oxygenates the bottom of the ocean.

• 10:40Michael Stevens?

  Yeah.

• 10:41Hannah Fry?

  I mean, that's cool.

• 10:42Michael Stevens?

  Oh, my gosh.

• 10:43Hannah Fry?

  That's fun, isn't it?

• 10:44Michael Stevens?

  You're welcome, fish.

• 10:45Hannah Fry?

  You're welcome, fish. Enjoy. But the thing about them, in terms of their future, is that all of the metals that are in here, which are extremely rare, once you come up to the surface of the earth, but you find them in this incredible concentration within these nodules, are exactly the same metals that you need to make, for example, electric cars, right, batteries in electric cars. So there is this kind of paradox that's going on at the moment, which is that to make cars greener, maybe we should do this really quite environmentally damaging thing, which is going-

• 11:15Michael Stevens?

  Sorry, I thought you were gonna say we should do this as an episode.

• 11:18Hannah Fry?

  No.

• 11:19Michael Stevens?

  Say that again.

• 11:20Hannah Fry?

  No, maybe we should.

• 11:21Michael Stevens?

  They're really damaging. I'm like, we should.

• 11:24Hannah Fry?

  Well, I don't know. It goes back to Howard Hughes' idea. Maybe we should really do Howard Hughes thing.

• 11:29Michael Stevens?

  Well, yeah, especially if metals and especially rare metals are congregating together because it's easier for them to move through water. We're never going to find nodules that form in that way in dirt.

• 11:40Hannah Fry?

  No.

• 11:40Michael Stevens?

  So mining, especially rare earth minerals, is a very intensive process. But the oceans already allowed time to collect them together.

• 11:50Hannah Fry?

  Yeah, although I think it probably would be quite disruptive to marine life if we went down there and got them. But there's like a lot of them. There's a lot. I mean, the ocean can spare some.

• 11:59Michael Stevens?

  The ocean, we can just borrow some.

• 12:00Hannah Fry?

  Yeah, exactly.

• 12:02Michael Stevens?

  We'll leave some trash down there in its place. I'm pulling Indiana Jones like, and here's, here's a bunch of straws.

• 12:08Hannah Fry?

  Yeah, you know, I sort of feel like I should lick it as well so that at least if you die, I die as well.

• 12:13Michael Stevens?

  I think it's one of those things that'll just slowly kill me. Or it'll lead to faster cognitive decline in decades to come.

• 12:23Hannah Fry?

  Look, you mess around with yellowcake, all right? This is licking a bit of rockers.

• 12:28Michael Stevens?

  I didn't lick the yellowcake, okay?

• 12:31Hannah Fry?

  Shall we do some questions?

• 12:32Michael Stevens?

  Let's do some questions, yeah.

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• 14:20Michael Stevens?

  So this question comes from Mike. Mike asks, can we train ourselves to be ambidextrous? I learned to shoot a basketball with both hands, but I feel like my non-dominant hand, left, will never be as good as my dominant, right, one. Well, you can. You can definitely train yourself to be ambidextrous. In fact, many left-handed people were forced to do this and to this day still train themselves away from it. It takes time, but handedness is a pretty big mystery still. We have some evidence of handedness in non-human animals, but it's not nearly as strong as it is in humans. And so the origins of handedness are kind of unknown.

• 15:05Michael Stevens?

  About 10% of people are left-handed. Only about 1% of people are ambidextrous. Like truly, they can do fine and gross motor skills equally well with both hands. I think the less dominant hand gets a bad rap, though, because maybe it's not good at certain fine motor skills, but it is a fantastic helper and follower. Like if you try to write on a sheet of paper with your non-dominant hand, which in my case is the left, not only does it have trouble forming the little letters, but my right hand has no idea what to do. I'm like, where do I put it? It's supposed to be holding the paper or moving it and I can't do it. But my left hand instinctively just is like, yep, here's where I'm gonna be.

• 15:50Hannah Fry?

  I'm there, my guy.

• 15:51Michael Stevens?

  The dominant guy. And when it comes to throwing a ball, the left hand, in my case, again, the non-dominant hand does a lot of work in terms of balance. And I find that when I throw with my dominant hand, my left hand knows exactly where to be to balance everything out and give me really great leverage. When I throw with my left, my right arm is like, whoa, hey, I'm in the way. I don't know how to, how to work them together. So really, they're like this great team. It's like a little Abbott and Costello, a little Hall and Oates, a little Simon and Garfunkel, a little peanut butter and jelly, a little, okay, I ran out of famous pairs off the top of my head. But yeah, you can train yourself and it's, it's worth doing as a party trick.

• 16:34Michael Stevens?

  But otherwise, I don't know, it's fine to just have a dominant and a non-dominant.

• 16:38Hannah Fry?

  I do wonder though whether it is better for your brain, because of course, your brain is sort of cross wide, right? Like the right hand side of your brain controls the left hand side of your body and vice versa. So I wonder about, I'm thinking about dementia here. I wonder whether if you train yourself to become ambidextrous, whether you're, I mean, in general, the more that you do to support your brain, to push it in directions that it doesn't feel comfortable in, the better that you can stave off dementia.

• 17:03Michael Stevens?

  I wonder, it could be good for your brain health. Cause it's certainly a cognitive exercise of a unique kind.

• 17:10Hannah Fry?

  Hmm.

• 17:11Michael Stevens?

  Could you train yourself to be the opposite of ambidextrous? Could you train yourself to be ambasinister? That's what it's called when you're not good with either of your hands.

• 17:22Hannah Fry?

  Right.

• 17:23Michael Stevens?

  Yeah. It's not a real thing, but yes, sinister means left and dextrous meant right. So.

• 17:30Hannah Fry?

  Is that a Google whack? Ambasinister?

• 17:32Michael Stevens?

  I don't think so, but look it up. But yeah, sinister meaning left shows you historically how we have treated left-handed people.

• 17:40Hannah Fry?

  Hmm. It is. It's a real word.

• 17:43Michael Stevens?

  It's a real, would I lie?

• 17:44Hannah Fry?

  I thought you, I.

• 17:45Michael Stevens?

  On this podcast?

• 17:47Hannah Fry?

  Sorry, I thought, um, yes, I thought you did.

• 17:50Michael Stevens?

  Well, I mean, did you think that I made it up, though it was would technically be like a word for it? Yeah, but it is a real thing.

• 17:57Hannah Fry?

  I did a program once on left handedness and I spoke to this neuroscientist called Sophie Scott, who's absolutely amazing. Like really brilliant science communicator as well as a scientist. Anyway, she told me this incredible story about something called left neglect. Have you come across this?

• 18:13Michael Stevens?

  No.

• 18:14Hannah Fry?

  So it's this really strange phenomenon where somebody gets a brain injury to the right hand side of their head. Okay, to the right hemisphere. And then they, as a result, uh, just don't pay attention to essentially anything on the left hand side.

• 18:31Michael Stevens?

  In the visual field even.

• 18:32Hannah Fry?

  Yeah, and it's not that they can't see it, because if they are, if they are told to look at it, then they see it. But they just, they just don't pay attention to it. So for example, you get people who have left neglect shaving half of their face, eating half a plate of food, not noticing it. I have a feeling that Dickens had this actually, uh, or there was someone, some famous writer who had it and then talks about just not noticing that lamp posts are sort of appearing on the left hand side. Anyway, Sophie was telling me about this study they were doing in hospitals in Manchester, where they were following doctors who had been on extremely long shifts. Okay, so I'm talking about serious sleep deprivation.

• 19:10Hannah Fry?

  Under these conditions, you also see signs of left neglect in these doctors, but only if they are right handed.

• 19:18Michael Stevens?

  Oh, what if they're left handed?

• 19:21Hannah Fry?

  So you don't see it, you don't see it. You see sometimes flickers of right neglect, but it's way more transient.

• 19:29Michael Stevens?

  Oh, strange.

• 19:30Hannah Fry?

  And I think there's some idea that you have, uh, this, this sort of resistance to these severe spatial biases, because your, your, your attention network is better distributed across the whole of your brain rather than just on one side. But it's like, yeah, I mean, active areas of research.

• 19:49Michael Stevens?

  Well, you gotta give those researchers a hand.

• 19:51Hannah Fry?

  Uh, which one?

• 19:53Michael Stevens?

  But which one? We should also look more into the origin of handedness because until that question from Mike, I thought we knew what caused it and what the advantages were. And I thought that it was widespread in the animal kingdom. But one thing is, it's hard to find the origin because although we have pretty good evidence that Neanderthals exhibited handedness, that'll come from things like, how did they sharpen tools? And how did they hold something down while they worked on it? There's a way to figure it out. I know that with early humans, we find a lot of handprints, right? Where someone put their hand on a rock and then they sprayed the pigment on it to leave a negative impression of the hand. That almost

• 20:34Michael Stevens?

  all of those are left hands, which implies perhaps that more of them were right-handed because they were using the right hand to apply the pigment. But when you want to look at really ancient prehistoric people, the evidence is very conflicting. So we don't know when distinct human handedness emerged as we have it today, or why?

• 20:55Hannah Fry?

  We can promise you an episode on that's coming up at some point in the future. Here's a question from Asia. Do taller animals get struck by lightning more often? If so, I guess it's dangerous to be a giraffe.

• 21:05Michael Stevens?

  Do you know?

• 21:06Hannah Fry?

  I do know.

• 21:07Michael Stevens?

  What's the answer?

• 21:07Hannah Fry?

  Yes.

• 21:08Michael Stevens?

  Oh, no.

• 21:09Hannah Fry?

  Yes, but it's not the worst thing that can happen. So it is true. It is true that giraffes do get hit more often because they are sort of poking out of the savanna quite a lot more, which is a little bit tragic. There are also actual documented cases of giraffes getting hit by direct strikes during heavy thunderstorms.

• 21:27Michael Stevens?

  Oh, no.

• 21:28Hannah Fry?

  Actually, I think there was in 2020, there was, there was an observational study, people out in South Africa, you know, watching, watching what was going on. And two giraffes were killed by a single bolt. I think they were standing quite close to each other.

• 21:42Michael Stevens?

  Oh, no.

• 21:42Hannah Fry?

  So yes, it is more dangerous to be a giraffe, essentially.

• 21:44Michael Stevens?

  Makes sense.

• 21:45Hannah Fry?

  It is. But it's not the most dangerous thing when it comes to lightning because actually a direct hit from lightning from the sky is the least common way that the, that electricity can kill large animals. What is way more dangerous is because it's much more likely to hit the ground. And then you have this millions of volts of electricity that are rippling outwards through the soil. And here's the thing, if you're an animal who is on four legs. Two of your legs are going to be further away from the site than the other two, which means that there is going to be a differential

• 22:22Michael Stevens?

  Right.

• 22:22Hannah Fry?

  between those two points. This is called a step voltage. It's totally deadly for four legged animals. Um, and you know, you could maybe get really lucky where you were, you know, standing in a, in a way that was perfectly parallel with the rings as they, as they emerged. But at any other angle, there's going to be this difference between your front and back legs.

• 22:44Michael Stevens?

  So current will pass through its body.

• 22:46Hannah Fry?

  Yeah. Giraffes are more prone to this as well because obviously they're very big animals. Their front and back legs are really far apart. But this ground current effect, it was this incredible morbid mystery that sometimes you would see news reports of, you know, or in history more generally, you would see, I don't know, like an entire herd of reindeer or like dozens of cows that are just instantly killed in a single storm. And it could just take out an entire herd at the same time.

• 23:13Michael Stevens?

  And it was probably because lightning hit

• 23:16Hannah Fry?

  The ground.

• 23:16Michael Stevens?

  The ground. And then a difference in charge between their feet across space

• 23:23Hannah Fry?

  Yeah.

• 23:23Michael Stevens?

  got them all.

• 23:24Hannah Fry?

  This little electrical bridge, basically, that their bodies, their body, their bodies were the shortest path between the two.

• 23:29Michael Stevens?

  So if I'm stuck in a field during a lightning storm, should I keep my feet together?

• 23:33Hannah Fry?

  Yes, and tucked down.

• 23:34Michael Stevens?

  Stand on one leg.

• 23:35Hannah Fry?

  Or get in a car.

• 23:37Michael Stevens?

  Or get, well, yeah, okay. If I had a car, then I consider myself not stuck in a field.

• 23:41Hannah Fry?

  Or a giraffe. Yeah.

• 23:42Michael Stevens?

  I, I, I wouldn't get in a giraffe. Giraffe. We've got, we've got a lot of books from this country for my daughter where the rhymes don't work in my accent.

• 23:52Hannah Fry?

  Oh, really?

• 23:53Michael Stevens?

  Yeah. There's one about like, put a scarf on a giraffe. And I'm like, uh, Marnie, that's my wife. You have to read this one. And she's like, oh, put the scarf on the giraffe. And I'm like, okay, that sounds ridiculous, but it rhymes now.

• 24:08Hannah Fry?

  Excuse me, it sounds sophisticated.

• 24:09Michael Stevens?

  It sounds sophisticated and sexy, actually.

• 24:13Hannah Fry?

  She is.

• 24:14Michael Stevens?

  She keeps saying that the New Zealand accent was voted the sexiest accent. I'm like, that must be a comedian's joke because, just kidding, I think it's obviously true.

• 24:26Hannah Fry?

  Money, he listens to this podcast.

• 24:29Michael Stevens?

  Yeah.

• 24:30Hannah Fry?

  Um, I heard it was the Irish accent.

• 24:32Michael Stevens?

  Are you serious?

• 24:33Hannah Fry?

  Shall we have a look?

• 24:34Michael Stevens?

  Wouldn't, it should be.

• 24:35Hannah Fry?

  Do you reckon they have a new vote every year?

• 24:36Michael Stevens?

  British, Italian, French.

• 24:38Hannah Fry?

  Not British, come on.

• 24:40Michael Stevens?

  Yeah, well, come on, like a, like a, uh, what, what was her name? Um, Glamour Spice?

• 24:46Hannah Fry?

  Glamour Spice.

• 24:47Michael Stevens?

  Victoria Beckham, who?

• 24:48Hannah Fry?

  Posh Spice.

• 24:49Michael Stevens?

  Posh, Posh Spice.

• 24:52Hannah Fry?

  Do you, so are you joking? She's got like an Essex accent.

• 24:55Michael Stevens?

  I guess I haven't listened to her speak.

• 24:57Hannah Fry?

  Oh, maybe that's why you think she sounds great.

• 24:59Michael Stevens?

  But I would imagine Elizabeth Hurley.

• 25:02Hannah Fry?

  Yeah.

• 25:02Michael Stevens?

  That, her accent is, it's sophisticated, right?

• 25:06Hannah Fry?

  Like, that is very RP, yeah.

• 25:07Michael Stevens?

  Yeah.

• 25:08Hannah Fry?

  Yeah, I don't know. I think when people say English accent, I just imagine people from my hometown who are like, "Oi, shut up here, oh my god." I don't think that's sexy at all. But I imagine Italian people are the same. This question's from Paolo. I study statistics in Padua, Italy, which is in the middle of, uh, Pianura Padana, a region characterized by coldish, foggy winter days. I come from a city in the Alps that gets way colder than Padua, and whenever I tell my mom it was cold in Padua, she blames it on the dampness in the air, swearing that to her, a humid cold feels colder than dry cold even when fully clothed. So, is a 10 degrees Celsius, 80% humidity day colder than a 0 degrees, 50% day?

• 25:52Michael Stevens?

  Well, I mean, yeah, it's colder because the temperature's lower, but it will feel different. The humidity does make a difference. Humidity makes a hot day feel hotter and a cold day feel colder because water is a much better conductor of heat. So if it's cold outside and the air is cold but really dry, you might not feel as bad because you're not losing heat as efficiently into the air. But if that air is the same temperature but much more humid, then you can have that heat taken away from you, uh, much more quickly. I remember experiencing, I think in like North Dakota, a, a night where it wasn't even that cold. It was like 20 Fahrenheit, you know, it was below freezing, but it felt.

• 26:35Michael Stevens?

  Painfully cold. And I'm like, it's been this cold in Kansas before. And someone was like, the humidity is so high. Um, but do you, do you have anything else to say about this? Is that true?

• 26:46Hannah Fry?

  Yeah, yeah, no, I agree with you. I think, I think one of the, one of the additional weird things here, I think this strange biological quote that I can never get my head over is that humans actually can't sense wetness, right? We don't have like a wetness sensor. The only way that we can tell that something feels cold is if, is, is by the temperature differential to what we were expecting. When you get this, if you put, uh, Veritas did something on this recently. You put your hand in a, in a glove and into a glass of water and it feels like it's wet.

• 27:13Michael Stevens?

  Wet. Yeah, I saw that too. And I've noticed that too. Like I will often wear gloves when I'm uh, in the kitchen and then I'll wash the gloves. And I'm like, hey, my hands got all wet. And I'm like, oh no, they didn't. But yeah, it's just that temperature difference. So you can tell the humidity of the air because of, I mean, how it's interacting with your skin and temperature change, but, and also how it interacts inside your body with temperature change in your lungs. So.

• 27:39Hannah Fry?

  But you're not actually physically feeling the wetness.

• 27:41Michael Stevens?

  Funny enough too, humid air, do you think that it's more or less dense than dry air?

• 27:47Hannah Fry?

  I would guess more.

• 27:48Michael Stevens?

  It's less.

• 27:49Hannah Fry?

  No.

• 27:50Michael Stevens?

  Yeah, because water molecules, uh, water vapor, which is what is in air that makes it humid, is just uh, H two O. So it's two hydrogen atoms and one oxygen. That's it. And what is it replacing? It's replacing oxygen, which is two oxygen atoms, or carbon dioxide, which is carbon and two oxygen, or it's replacing nitrogen, which exists as N two. So the water vapor is replacing molecules that are much heavier. So humid air is a lot less dense, even though it feels like oppressively dense. It's not. And so there actually was a case where a baseball team got in trouble because they had an indoor baseball stadium.

• 28:32Michael Stevens?

  And whenever their opponents came up to bat, they would turn on the air conditioning to make the air thicker so that balls wouldn't go as far.

• 28:39Hannah Fry?

  Wow.

• 28:40Michael Stevens?

  Yeah. And when they were up to bat, they would let the natural humidity come back in so that the air became thinner and balls were slowed down less.

• 28:47Hannah Fry?

  That's incredible.

• 28:48Michael Stevens?

  And they were told to stop.

• 28:49Hannah Fry?

  Yeah, I mean, that's absolutely.

• 28:51Michael Stevens?

  But that's really counterintuitive because humid air, you go down to like the Gulf Coast and you're just like, oh, this it's so thick, the air is thick and it feels heavy, but it's actually much less dense.

• 29:02Hannah Fry?

  Well, actually, I mean, if you, if I'd paused to think about it for longer, of course, humid air has to be lighter. Because otherwise clouds, you know, clouds wouldn't work. Clouds wouldn't be up there, they'd be down there.

• 29:12Michael Stevens?

  I guess so. Well, if they come down, also the pressure increases. And the temperature goes up.

• 29:21Hannah Fry?

  Mm hmm.

• 29:22Michael Stevens?

  So the water, well, yeah, no, I'm sure you're right.

• 29:25Hannah Fry?

  Yeah.

• 29:25Michael Stevens?

  I don't know enough about.

• 29:26Hannah Fry?

  If clouds were really heavy and dense, then they'd be below.

• 29:29Michael Stevens?

  But clouds aren't water vapor. Clouds are drops of liquid water that are visible.

• 29:34Hannah Fry?

  Oh.

• 29:35Michael Stevens?

  Yeah.

• 29:36Hannah Fry?

  Okay, I take it.

• 29:36Michael Stevens?

  Water vapor is completely invisible, but once it condenses into droplets of water that that float because they're so small, then you've got a cloud.

• 29:46Hannah Fry?

  Okay, all right, I take it back.

• 29:47Michael Stevens?

  It's kind of like a pedantic thing I get into as well.

• 29:49Hannah Fry?

  Class, class, class, class, stay where they are.

• 29:50Michael Stevens?

  Like when you've got your kettle on and you see the steam coming out, no, you don't. Because steam is water vapor, which is invisible. What you're seeing is water vapor, water in a gas form that has condensed into liquid droplets. And those are what you see as the white smokey steam, but that's not steam, that's just hot drops of liquid water.

• 30:10Hannah Fry?

  This is why we love you, Michael, because there are very few other people on earth who would be like, no, you're not seeing steam.

• 30:15Michael Stevens?

  You can't see steam.

• 30:17Hannah Fry?

  You can't see steam. Um, okay, just to round off this episode, I've actually, I've looked up the, uh, the, the, who, what has been voted the, the sexiest accent.

• 30:25Michael Stevens?

  Okay, tell me.

• 30:26Hannah Fry?

  Okay, the, um.

• 30:27Michael Stevens?

  Wait, let me guess. Tell me, tell me two and three.

• 30:31Hannah Fry?

  Okay.

• 30:31Michael Stevens?

  Tell me third place, second place, I'll tell you first.

• 30:33Hannah Fry?

  They kind of, they change around a little bit depending on who's asking, who's asking.

• 30:36Michael Stevens?

  I'm sure.

• 30:37Hannah Fry?

  But the top four, we got all of the top four.

• 30:40Michael Stevens?

  Okay, so the top four are French, Italian.

• 30:44Hannah Fry?

  Not French, actually, sorry.

• 30:45Michael Stevens?

  Oh, what are the top four?

• 30:47Hannah Fry?

  Italian, British, Irish, Kiwi.

• 30:52Michael Stevens?

  Number one?

• 30:53Hannah Fry?

  Yeah.

• 30:54Michael Stevens?

  So my wife is right.

• 30:56Hannah Fry?

  Yeah. In a heavily debated 2019 poll by Big Seven Travel, it took first place at 50 accents. They described the New Zealand accent as outrageously charming, allowing it to beat out South African accent and the Irish accent. Yeah.

• 31:14Michael Stevens?

  I stand corrected that my wife is right.

• 31:16Hannah Fry?

  There you go.

• 31:17Michael Stevens?

  Yeah.

• 31:17Hannah Fry?

  There you go. Your marriage can go on happily.

• 31:21Michael Stevens?

  I'm trying to do an impression of a New Zealand accent, but it's going to be so offensive and wrong.

• 31:26Hannah Fry?

  Go on, do it anyway.

• 31:26Michael Stevens?

  I just think it's like, this is my New Zealand accent. Oh, do you like a beer?

• 31:33Michael Stevens?

  Is that, is that good?

• 31:34Hannah Fry?

  I'm not sure what you were saying.

• 31:37Michael Stevens?

  Oh, go on the dick. Like that.

• 31:39Hannah Fry?

  Go on the dick?

• 31:41Michael Stevens?

  Yeah. Oh, that sounds better. I don't know why I make it so high pitched.

• 31:46Hannah Fry?

  I enjoy it so much more that you're just high pitched.

• 31:49Michael Stevens?

  I'm gonna try like lower. Oh, come on, on the dick, go be a sweet ass.

• 31:55Michael Stevens?

  That was good.

• 31:56Hannah Fry?

  You know what?

• 31:57Michael Stevens?

  Straight out of.

• 31:57Hannah Fry?

  I think, I think that was undeniably sexy.

• 32:01Michael Stevens?

  How do they say hello? Hello, I'm from the South Island, eh?

• 32:08Michael Stevens?

  That was good.

• 32:09Hannah Fry?

  I felt like I was there. That was, uh.

• 32:11Michael Stevens?

  And the North Island is more like, eh, a sweet ass, oh, give me some, uh, Milo.

• 32:19Hannah Fry?

  Yeah, it is a wonder that you didn't choose acting as your career.

• 32:22Michael Stevens?

  Isn't it?

• 32:23Hannah Fry?

  Hmm, it absolutely is. I think.

• 32:27Michael Stevens?

  I think that if you've been offended today, let us know. You can email us at [email protected].

• 32:32Hannah Fry?

  Send us in your questions, your, your ideas, things you want us to answer, and any medical advice for somebody who's consumed a small amount of bala polymeric nodules.

• 32:42Michael Stevens?

  Lead. Or, yeah, nodules. Goodness.

• 32:46Hannah Fry?

  See you next time.

• 33:01Speaker 06

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