Answers to Your Science Questions

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Speaker 13 BBC Sounds, Music, Radio, Podcasts. Welcome to the podcast of BBC Inside Science with me, Marnie Chesterton.
The show was first broadcast on the 17th of April, 2025.

Speaker 13 Humans are curious creatures. I'd say it's the key to our success on this planet.
This This fundamental desire to ask why, what and how, what's beyond this mountain, how can I preserve my milk supply?

Speaker 13 Why are my feet cold? It's how we spread across every continent on the earth and invented cheese and socks.

Speaker 13 And what is science but a systematised desire to understand, to scratch that curiosity itch in a methodical manner that gives you reliable, evidence-based answers.

Speaker 13 And since Inside Science is your hub for science on Radio 4, it's no surprise that some of you have contacted us with questions about how the world works.

Speaker 13 And yes, knowing that today was coming up, I have actually also been asking you to email insidescience at bbc.co.uk with anything science-flavoured that's been puzzling you.

Speaker 13 Today, we've assembled a panel with decades of dedicated study between them and we'll be tackling a selection of your questions on everything from the cosmos to the direction of snail travel.

Speaker 13 Let's meet them.

Speaker 14 Hi, I'm Professor Catherine Haymans. I'm a professor of astrophysics at the University of Edinburgh and I'm also the Astronomer Royal for Scotland.

Speaker 1 I'm Professor Mark Mazzin and I'm a professor of Earth system science, which usually people go, what's that?

Speaker 1 So basically I study climate change in the past, the present and the future.

Speaker 15 And I'm Dr. Penny Sarche.
I'm Managing Editor at New Scientist.

Speaker 13 Great.

Speaker 13 Well, welcome, gang. Good to have you with us.
This is a discussion, by the way. So I'm going to pitch a question to one of you.

Speaker 13 But if anyone else wants to join in, contradict anything else, pick a fight, then you can do so. Catherine, we're going to start with a short question about the cosmos.

Speaker 13 Philip wants to know, why are planets round?

Speaker 14 I'll give you a short answer, Marnie. Gravity.

Speaker 14 Do you want me to expand?

Speaker 1 Yes, please.

Speaker 13 No, moving on. We've got a lot of questions to get through.

Speaker 14 So gravity is the force that pulls you down after you've jumped up in the air and it always pulls you to the center of the earth, no matter where you might be jumping around on the surface of our planet.

Speaker 14 Now, about 4.5 billion years ago, when our planet formed, it was a hot, liquid rock, and there were no people jumping around on the planet, obviously, but gravity worked in exactly the same way, pulling everything towards the center in all directions.

Speaker 14 And if you do that, if you've same force pulling in all directions, you end up with a sphere.

Speaker 13 But there wasn't a center. Hang on, there wasn't, you say, towards the centre of the Earth, but there wasn't an Earth.

Speaker 14 Well, so in the very early universe, we've got lots of stuff swirling around the solar system.

Speaker 14 We don't really completely understand how planets form, but there would have been a clump of matter with more gravity than the rest pulling things towards it.

Speaker 14 And it keeps pulling and pulling and pulling, and that's in all directions, and that's how you end up with a sphere. Okay.

Speaker 14 But there's a bit of a twist because planets also spin, so there are more forces involved than just gravity. And so they're not perfect spheres.

Speaker 14 And you can see this particularly with the planet Saturn. That's spinning so quickly that it kind of squashes at the poles and bulges out at the edges.

Speaker 14 But yeah, planets definitely round thanks to gravity.

Speaker 13 Is there anything that doesn't fit the formula? I'm thinking of, you know, I mean, it's not planet size, but the comet 67P that hit the headlines.

Speaker 13 I mean, that notoriously looked a a bit like a rubber duck.

Speaker 14 So

Speaker 14 comets, asteroids, things like that, they're much smaller. They form in different ways.
They don't have so much gravity to pull everything towards them. So you don't get that nice round shape.

Speaker 14 They also tend to sort of collide into each other in the asteroid belt. So they get all sorts of strange shapes because of that.

Speaker 13 So no cubes, no cube-shaped planets lurking in there.

Speaker 14 No cubes. No cubes known of as yet.

Speaker 1 And if you do see any cubes, they're probably aliens. There we go.

Speaker 13 Moving on from planets to life on this planet, and Mark, I'm batting this one your way. Take a listen to this from Jeff.

Speaker 16 I've got a question for you, which seems simple, but I'm struggling to get my head round it. How do trees grow?

Speaker 16 When I look at a cross-section of a tree trunk, the annual growth rings are generally uniform in thickness along their length, just with some variation between rings in good or bad growth years.

Speaker 16 How does the tree manage the growth of each ring in a consistent manner? Also, the amount of material a tree has to manufacture increases each year as it gets bigger.

Speaker 16 Does that mean trees have to work harder every year?

Speaker 13 So what is an Earth system scientist doing knowing anything about trees, Mark?

Speaker 1 Oh, so I hide in the geography department. So again, I've been sort of like bombarded with all the physical sciences.

Speaker 1 Last week we were in the Greek islands with our wonderful undergraduates and we were taking tree course to actually look back to see how trees grow but also how they reflect the climate change of the region.

Speaker 1 And to answer the question, trees don't grow at the same rate through their lives.

Speaker 1 Interestingly enough, when they're young they grow very rapidly, but the tree rings aren't necessarily distinct even though they're thicker.

Speaker 1 And so what our eyes are drawn to are the beautiful regular sort of layers that are produced when the tree is matured.

Speaker 1 And they seem to look similar in size, but as the listener absolutely correctly said, we have thicker rings for good years and we have thinner rings for poor years. But why do we have these rings?

Speaker 1 So the first thing is in a temperate climate like the UK,

Speaker 1 Trees grow with two rings. The first one is a lighter ring, which occurs in spring and early summer, and then there's a darker ring that represents wood in the late summer and autumn.

Speaker 1 Now, trees always try to add as much wood as they can, but remember they're limited by the amount of sunlight, the amount of water, and nutrients.

Speaker 1 But they also have a balancing act, which is yes, they want to grow as much as possible, but they also want to reproduce.

Speaker 1 And so, the tree is constantly trying to balance: hey, I've got to actually produce fruit, I've got to produce acorns, I've actually got to reproduce at the same time as growing.

Speaker 1 But as the tree grows and matures, you will see that the rings do get thinner, and trees get to that point where they get to an old age. What's really interesting about trees is they constantly grow.

Speaker 1 This is the way they avoid old age by growing and growing and growing. And they do get to a point where suddenly old age and decay catches up with them.
I'll give you an example.

Speaker 1 English oak can produce acorns by the age of 40. Okay, so 40 is when they've hit adulthood.

Speaker 1 They will then be very productive between 80 and 120 years old, and they can be productive for another 300 years.

Speaker 1 They then go into this old age where they're still growing, so that keeps off the whole decay and dying for another 300 years.

Speaker 1 And then that's the end game. Whereas if you compare, let's say, rowan trees, they produce fruit and berries around 15 years, and maximum life is about 120.

Speaker 13 Okay, round the table, I should say, Dr. Penny Sasha has a PhD in plant genetics, so she's marking your work here.

Speaker 1 Please say I got it right.

Speaker 1 No obvious errors there, Mark.

Speaker 15 All I would add is that yes, trees do have to, the bigger they are, the more they do need to work. They need more energy, so that's why they have more leaves, a bigger tree naturally.

Speaker 15 And also, it's not precise, but as a sort of rule of thumb, if you look at the mass of a tree above ground, that's approximately the mass of the roots underneath as well.

Speaker 15 So the root system is growing and that really does power that growth and being bigger because yes, more energy is needed when it's a bigger size.

Speaker 13 Sticking with life on Earth, Penny, we've had a question from Matt about some non-plant life. Let's listen.

Speaker 17 I have a question about the skeins of geese which fly over our house on their way to the local salt marsh at Martinmere.

Speaker 17 They're very noisy, constantly calling to one another. Can anyone translate what they're saying? Is it follow me, I know the way?

Speaker 1 Or wait for me?

Speaker 17 Are they discussing last night's T V?

Speaker 17 Whatever it is, it must take quite a lot of energy and that makes me think it must be important. Can you shed any light on this?

Speaker 15 It's a great sound. I just want to grab my binoculars and head outside.
I think energy is a a really interesting way of looking at this actually.

Speaker 15 We don't know exactly what they're saying, but clearly they are communicating. And I'm sure there's a degree of which way are we going? How fast are we going? That's too fast for me.

Speaker 15 That looks like a really nice feel down there.

Speaker 15 But a lot of what we think they're talking about with all of those very noisy honks is their formation because geese and ducks famously they fly in this V formation.

Speaker 15 And what's clever about that is it minimizes drag for those who are flying behind, but it means it's much harder work when you're the leader. So they take turns.

Speaker 15 And if you think about it, that's actually quite a difficult thing to coordinate in mid-flight, swapping.

Speaker 15 I'm sick of this, I don't want to do it anymore, it's your turn.

Speaker 15 So, there is some thinking that quite a lot of the loud honking is just required to keep them in that formation and make sure that it's fair.

Speaker 13 So, sort of like, is it encouraging honks? Like, come on, keep going, you can keep doing this.

Speaker 15 Yeah, or maybe I like to think they're squabbling, like, no, it's your turn. I've been doing this, you know, long enough now, and it's time for me.

Speaker 1 I'm not breeding.

Speaker 1 I love the fact that sort of like what you've got is somebody in the front going, oh, Bert, back left, it's your turn, get up here. And the bird going, nothing to do with me, I'm happy flying.

Speaker 15 Consistent with what the personality of geese seems to me.

Speaker 1 Yeah, yeah.

Speaker 13 Does anyone know where we are on sort of Dr. Doolittle science of talking to animals?

Speaker 15 There was a really good study the other week that found that some birds, I think it was a type of parrot, they have a mental map of sounds that is really similar to the ones that we convergently have.

Speaker 15 So there's still kind of really foundational discoveries being made there, but the more we look, the more complex communication between animals, particularly birds, but all kinds of animals, is turning out to be.

Speaker 15 I know I have colleagues who really do think AI is going to decode what whales are talking to each other about. I think that is potentially possible.
I'm excited about that.

Speaker 13 I'm excited about that. There's a thing called Project SETI, which is funded by Silicon Valley Money, and they claim that they're going to use large language models to try and decode whale language.

Speaker 13 And they've put 2026 as their

Speaker 13 soon, I know, as their deadline for a conversation between a person and a whale.

Speaker 14 But how do they train the data? Because you need a truth. With AI models, you need a truth.

Speaker 1 Yeah.

Speaker 14 And so how do they know? You need at least a starting point of what the communication is about.

Speaker 15 I imagine we must have decades of people out on boats making observations and recordings, I suppose. And can we just feed this into an AI to process them all?

Speaker 13 Our next question takes us back up to the stars. So, Catherine, this one's definitely for you.
And it's from Tricia.

Speaker 18 When we look up at the stars, why are we always looking into the past? Surely, if the Earth is revolving, at some point we should be looking at where we are going, the direction we are travelling in.

Speaker 13 So, a lot to unpick here.

Speaker 13 Catherine,

Speaker 13 why is looking down a telescope like looking back into the past?

Speaker 14 Let me try and explain.

Speaker 14 So I want you to imagine that we've built a road between Earth and the Sun and we're going to drive along this road at the speed limit set by the British government for motorways.

Speaker 14 So we're going to drive along it at 70 miles per hour and at that rate it will take us 150 years to get from the Earth to the Sun.

Speaker 14 Now the sunlight as it comes back to us on planet Earth, it's effectively going along our imaginary road as well.

Speaker 14 Now, its speed limit is governed by the universe. So there's a maximum speed limit in our universe, which is 300 million meters per second.

Speaker 14 And that means that the light from the sun takes eight minutes to make that journey from the sun to Earth.

Speaker 14 So on a sunny day, if you could look at the sun, don't directly look at the sun, but if you could, you would be seeing... an image of the sun as it was eight minutes ago.

Speaker 14 And so astronomers can use this phenomenon in our universe that there's this maximum speed limit for light

Speaker 14 to time travel. The further we look away in our universe, the farther back in time we're looking.

Speaker 14 So when we get out our telescopes and we look at our nearest neighbor in the universe, Andromeda, the galaxy of Andromeda, we're seeing an image of it as it was two and a half million years ago, just because it's taken the light that long to travel across the universe towards us.

Speaker 14 And we've got fantastic new technology now. There's a brand new telescope up in space, the James Webb Space Telescope, that's allowing us to look incredibly to far distances in the universe.

Speaker 14 And we're seeing galaxies as they were when the universe was just 300 million years old.

Speaker 14 300 million years sounds like a long time, but in astrophysical terms...

Speaker 1 It's nothing, is it? It's nothing.

Speaker 14 It's the very, very early stages of the universe when galaxies were first forming. So astronomers can time travel back in time by looking really far away.

Speaker 14 But Tricia was wanting to to know can we look into the future because we're she's she's right that the earth is spinning around once every 24 hours that gives us night and day and we're also moving around the Sun

Speaker 14 but the reason why we can't see into the future is because of that that maximum speed limit again if we wanted to look into the future we would have to travel faster than the speed of light so we could kind of get ahead of it to to look at what's happening in the future and unfortunately Einstein with his theory of general relativity says that that's not possible.

Speaker 14 Our universe has a maximum speed limit, and that means we can look back in time, but not into the future, no matter how fast we're moving.

Speaker 13 There was an experiment recently where people said, Well, we think we've broken, we've found something faster than the speed of light.

Speaker 14 Yeah, as with a lot of great claims like that, unfortunately,

Speaker 14 it was neutrinos, and unfortunately, it boiled down to just a problem within the instrumentation.

Speaker 1 Oh, a coward. Because that would have been well cool.

Speaker 1 It would have. It would have.

Speaker 14 It would have been so cool.

Speaker 13 All those headlines. Einstein was wrong.

Speaker 14 I try,

Speaker 14 in my day job, I do experiment with different theories of gravity to try and explain all the dark stuff out there.

Speaker 14 And I skip up Blackford Hill in Edinburgh, up to the Royal Observatory each morning thinking, will I prove Einstein wrong today? And I can't. It's really, really good theory.

Speaker 14 It's so hard to find any problems with it whatsoever. So alas.
Time travel only to look to the past, not the future.

Speaker 13 Are we going to carry on, Catherine,

Speaker 13 finding older and older things to look at?

Speaker 13 How far back in the universe can we go?

Speaker 14 Yeah, so the James Webb Space Telescope was designed to look back, to look really far away in our universe, to look incredibly far back in time, to see the birth of the first stars and the galaxies.

Speaker 14 And it has, oh, what a Christmas present that was for astronomers across the globe because it has delivered a huge number, a surprising number of really massive galaxies in the very early universe.

Speaker 14 And it's really making us scratch our heads of how did these very bright massive galaxies form so early on in the universe and that's one of the the biggest questions in in astronomy at the moment is what on earth is going on in the early universe and and it's thanks to this new technology that and this time traveling trick that allows us to to peer back in time to see what was going on then and we don't understand it at the moment but that's the way science works isn't it we'll think about it and scratch our heads and build a big telescope and then we'll have a better idea.

Speaker 13 Just ask someone for more money for an even bigger telescope.

Speaker 14 Wow, you can't go wrong with a bigger telescope, honey.

Speaker 13 Thank you, Catherine.

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Speaker 13 You're listening to Inside Science with me, Marnie Chesterton, and this week we've turned the whole show over to listeners' curiosity and helping to provide answers.

Speaker 13 We have Penny Sachet from The New Scientist, Catherine Haymans from Edinburgh University, and Mark Maslin from University College London. Mark, next question, definitely a Mark question.

Speaker 13 Andy wrote to ask, I remember hearing that if we hit four degrees of warming, we will inevitably hit 10 degrees of warming because we will hit so many tipping points they will effectively trigger one after another.

Speaker 13 Is this true? And if so, do we know any more details about the tipping points and which ones we're likely to hit at lower levels of warming?

Speaker 1 So we're unlikely to hit four degrees warming. With the current policies, we're looking at about 3.1 to 3.7 degrees warming.

Speaker 13 That's nearly four.

Speaker 1 That's nearly four. But if the pledges that were made at the climate conferences come through, we're looking at 2.4 to 2.8.
So that's bringing it down.

Speaker 1 So those disasters that we were talking about 10 years ago, when we were looking at five or six degrees or beyond, those have receded in science because of the changes in policy and economics.

Speaker 1 and basically because renewables are just so much cheaper than fossil fuels. But having said that, we are worried about tipping points because we have a target.

Speaker 1 So the Paris Agreement 10 years ago said we should hit 2 degrees maximum with an aspirational target of 1.5 degrees. Now, last year we hit 1.6 degrees warming.

Speaker 1 So we've already pushed through that limit once.

Speaker 1 And if we say there consistently, then there are four four tipping points that we are particularly worried about which is the collapse of the Greenland ice sheet the collapse of the western Antarctic ice sheet the die-off of tropical corals and boreal or temperate sort of permafrost abruptly melting and and sorry what is a tipping point what defines that as a tipping point so a tipping point is a place in the climate where things irreversibly change and so therefore you have a Greenland ice sheet, it's melting, and we know it's melting quite rapidly.

Speaker 1 But there is a tipping point where that melting becomes inevitable, i.e., the whole ice sheet will go.

Speaker 1 Now, it may take a couple of hundred years, but the processes have started and cannot be reversed. That's a tipping point.
So, these are quite big, scary thing.

Speaker 1 The interesting thing is, those ones that we're worried about, they will increase sea levels with the melting of those ice sheets. They will cause local regional warming.

Speaker 1 So you'll have more warming in certain regions, particularly the Arctic, but they're not going to double glowing warming.

Speaker 1 They're not going to suddenly emit so much carbon that they're going to double and go from four degrees to 10 degrees.

Speaker 1 So the tipping points are worrying for other reasons, not the actual doubling of climate change. And again, I think this whole worry about 10 degrees, I'm really sorry.

Speaker 1 Things that are happening now around the world, all those extreme weather events, are scary enough.

Speaker 1 If we get to two degrees, there's a brilliant report by the IPCC that says, look at all the things that are going to happen at two degrees, which is scary enough.

Speaker 1 So we don't need to even be scared by four degrees. We need to be scared by one and a half to two degrees.

Speaker 1 What's going to happen?

Speaker 13 Brief summary?

Speaker 1 Brief summary. So you're looking at more extreme weather events that are going to occur more regularly.
So look at the Californian wildfires.

Speaker 1 Everybody seemed to be surprised, even though though climate scientists have said when this will happen in the future. Not if, when.

Speaker 1 I mean, let's go back and be really selfish and look at, say, the UK. In 2022, we had a heat wave that hit 40 degrees Celsius in July.

Speaker 1 Now, as a climatologist, the peak temperature in July for the last 10 years is 24 degrees. This is why we go on holiday.
Okay.

Speaker 1 This is 16 degrees warmer than it should have been. Let me repeat that.
16 degrees warmer. Okay.
So this is something we were predicting for 2050 and occurred in 2022.

Speaker 1 So the real effects of climate change are already here and impacting. And so therefore, we should be worried about one and a half to two degrees.

Speaker 1 Again, if we ever go near four degrees, that will be hell and earth. Forget actually going beyond four degrees.

Speaker 15 I saw the UK has recently committed quite a lot of money into setting up like an early warning system for predicting if tipping points are kind of if we're heading towards setting them off.

Speaker 15 By that logic, then we should actually already be really worried about what's happening now rather than worrying about these much more catastrophic things that are potentially weigh in the future.

Speaker 1 Oh, absolutely.

Speaker 1 And I have to say, a dear friend and colleague of mine, Tim Lenton, at Exeter University, has been really leading the charge into understanding the science of tipping points because it's one of those things which we can model the future given sort of like emissions.

Speaker 1 But what what we want to know is about the chaos in the system. How will these systems actually hit thresholds? And that's really difficult to do.
But we need to understand.

Speaker 1 We need to understand: are we in a position where we're going to collapse the circulation of the North Atlantic Ocean? Are

Speaker 1 AMOC. AMOC.
Oh, yes, AMOC. And again, most scientists will look at that and go, the science says not in this century.
But you then have some studies that go, no, it happened in the next 10 10 years.

Speaker 1 And you have to be very gentle about sort of like understanding the likelihood of these tipping points. For me, climate change is scary enough.

Speaker 1 What's happening around the world and what's going to happen around the world in the next 10, 20 years is very, very scary. We don't need to add onto that the horror stories of tipping points.

Speaker 1 We need to be aware of them and look at the science, but actually we need to reduce our emissions now.

Speaker 13 Moving on from the big Anthropocene shaping questions to the smaller queries, science puzzles lurking in your own backyard, Eric Johns got in touch with this question.

Speaker 20 At night, garden snails climb up the side of my house. The house is rough cast, so it's not an easy thing to do, and they get at least as high as the first floor, perhaps higher.

Speaker 20 What on earth are they trying to achieve? It doesn't seem to be a particularly useful thing for them to do.

Speaker 13 Thank you, Eric. So, Penny, I've decided that the plant scientist on the team, your remit includes garden pests, too.
Any answers to Eric?

Speaker 15 It certainly does in my spare time, I have to say.

Speaker 15 Forget dark energy. This is like the real mystery.

Speaker 13 What are they doing?

Speaker 15 There are so many theories about this and not enough evidence. Really?

Speaker 1 Yeah.

Speaker 15 So there are some really obvious ones like snails climb so that when they rest they don't get stepped on or they climb to avoid predators. Also when it's quite warm, if they climb up it's cooler.

Speaker 15 None of that really explains to me why they climb so high. There's also a theory that maybe they're going up to the guttering to lay their eggs up there.

Speaker 15 That seems eminently observable and testable but I, to my knowledge, no one has tested that yet.

Speaker 15 To me I think it immediately makes me think of a lot of snails sort of evolved in shoreline maritime environments where they are climbing up hard rocky faces.

Speaker 15 So maybe it's just they have this exploratory vertical behavior, and for some reason, they're just doing it on your house.

Speaker 1 But there's also some quite wild ones out there.

Speaker 15 One suggestion is they might actually be eating the wall, especially if this is pebble dash. They might be getting calcium from the cement.

Speaker 15 And I don't know that we know that the snails we have in this country do it, but some certainly do do that. African land snails, apparently.

Speaker 15 But my favourite one is some kind of parasitic fungus has taken over the snails and is driving them up to the top of the house so that the spores can be released and its evil life cycle can continue.

Speaker 15 But what strikes me with all of these ideas, which are quite fun to unpick, these are all testable. And this is a perfect undergraduate summer project.

Speaker 15 So if anyone wants to go out there and solve this question for us, I'm sure they can.

Speaker 13 Thank you, Eric, for that question.

Speaker 13 Moving on, just squeezing in one more. And finally, we've received this question from Amanda.

Speaker 21 Dear Inside Science Team, please could you find out and explain why when I put a duvet cover in the washing machine with other items they all end up inside the duvet cover when the programme finishes.

Speaker 21 Is it because of some identifiable hydraulic or fluid dynamic characteristic? I'd love to know and even try to understand.

Speaker 13 Right, so

Speaker 13 thank you so much, Amanda, for the question. We have a plant scientist, a climatologist and an astronomer.
So who's taking this?

Speaker 15 I'd like to argue this might be a little bit like cell biology.

Speaker 1 Okay, bear with me.

Speaker 13 Penny, floor's yours.

Speaker 1 So I have thought about this on a weekly basis for as long as I can remember.

Speaker 15 And I think what might be going on here is obviously when you've got a duvet cover and if you haven't sort of buttoned it up before putting it in the wash, you've got a very wide opening.

Speaker 15 So that's easy statistically for things to enter it. And then as it twists around in the wash, it's actually harder to leave.
So what you've got is kind of a difficulty gradient.

Speaker 15 Things are more likely to go in than they are to come out. And my reckoning is if that keeps happening for a long enough period, enough cycles, eventually everything ends up inside.

Speaker 15 And the reason I kind of try to claim that's like cell biology is sometimes certain substances, it's much easier for them to get into the cell through the cell membrane because of the way it's made than it is for them to randomly diffuse out again.

Speaker 15 And that's a really sort of clever, not kind of actively driven way of creating order or something really weird like you observe in your washing machine.

Speaker 15 That's my theory anyway, and I'm sticking to it.

Speaker 14 I've got an alternative hypothesis, Penny. Uh-oh.
I just think the duvet cover's hungry.

Speaker 14 But I'll defer to you on that one.

Speaker 13 I mean, so there's your astronomer's answer and

Speaker 13 your cell biologist's answer.

Speaker 13 Thank you so much, Amanda, for the question.

Speaker 13 That's us out of time. Thank you to our panellists, Dr.
Penny Sachet from The New Scientist, Catherine Haymans from Edinburgh University, and Mark Maslin from University College London.

Speaker 13 Thanks to our listeners for getting in touch. A reminder that if you have a question, the email address is insidescience at bbc.co.uk.
And I hope everyone has a lovely Easter break.

Speaker 13 Until next time, bye from me.

Speaker 13 And that's it. You've been listening to BBC Inside Science with me, Marnie Chesterton.
The producers were Dan Welsh and Debbie Kilbride. The show was made in Cardiff by BBC Wales and West.

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Speaker 4 Sucks!

Speaker 6 The new musical has made Tony award-winning history on Broadway. We demand to be home.
Winner, best score. We demand to be seen.
Winner, best book. We demand to be quality.

Speaker 9 It's a theatrical masterpiece that's thrilling, inspiring, dazzlingly entertaining, and unquestionably the most emotionally stirring musical this season.

Speaker 8 Suffs!

Speaker 11 Playing the Orpheum Theater October 22nd through November 9th.

Speaker 7 Tickets at BroadwaySF.com.