Instant Genius - How the evolution of eggs has shaped life on Earth

Episode Date: May 9, 2024

If most of us hear the word ‘egg’ it’s likely our minds will immediately turn to the hens’ eggs that we enjoy fried, poached or scrambled for our breakfast. But on closer inspection it turns out that the natural world is filled with all manner of different kinds of eggs that are as varied and fascinating as the animals that produce them. And what’s more, eggs have helped to shape life on Earth as much as life has shaped them. In this episode I speak to zoologist and award-winning science writer Jules Howard about his new book Infinite Life: A Revolutionary Story of Eggs, Evolution and Life on Earth. He tells us about the fascinating evolution of eggs over hundreds of millions of years, the strange and varied forms they’ve taken over all of this time, and how the story all began with jellyfish. Learn more about your ad choices. Visit podcastchoices.com/adchoices

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fascinating ideas in science and technology today. I'm Jason Goodyear, commissioning editor of BBC Science Focus. If most of us hear the word egg, it's likely our minds will immediately turn to the hens eggs that we enjoy, fried, poached or scrambled for our breakfast. But on closer inspection, it turns out the natural world is filled with all. all manner of different kinds of eggs that are as varied and fascinating as the animals that produce them. And what's more, eggs have helped to shape life on earth as much as life has shaped them. In this episode, I speak to zoologist, an award-winning science writer Jules Howard, about his

new book, Infinite Life, a revolutionary story of eggs, evolution and life on earth. He tells us about the fascinating evolution of eggs over hundreds of millions of years, the strange and varied forms they've taken over all of this time, and how the story all began with jellyfish. So first off, welcome to the podcast. Thanks very much for joining us. Thanks a lot for having me, Jason. What a pleasure. Oh, you're welcome, likewise.

So first off, can you briefly introduce yourself and tell us a bit about your background? So my name's Jules. Jaws Howard. I'm a zoological correspondent and writer, and I've been writing about the science of animals for about 20 or so years. and yeah, I've done lots of writing over the years about various subjects, mostly about evolution, about taxonomy, and about different animal groups, but also about wildlife conservation and how those two things kind of fit together.

So yeah, I'm really proud, I suppose, but especially proud of this book. Yeah, all good stuff. So that brings us on to the topic of today's conversation, your new book, Infinite Life, and it's all about eggs. So from the outside, that seems like quite an unusual topic. So what got you interested in it? Yeah, that's a really good question, actually. I did a project about four, five years ago,

some of your listeners might know about, which was basically making a three-dimensional kind of ghost train ride through a duck's genitalia. It was like a virtual reality one, so you put on a headset and you travel through. And that sounds incredibly random and strange by the time that it was a really good point I was making with the team of scientists.

I was working with that we just don't express enough joy about female genitalia. It's very much, when we talk about animals, we're often talking about male genitalia, because you can study that. So I've got my 3D headset on, and I'm travelling through this genitalia, this duck's vagina. And whilst doing that project, with a headset on a lot, because you obviously have to do a lot of testing because this thing was released for free into the public domain. And I was kind of like, wow, it's really interesting in here.

You know, we don't think about the insides of females, particularly when it comes to eggs. We don't think about the fact that actually egg construction is incredibly. incredibly finessed by evolution for hundreds of millions of years. And I think that was the first time I thought, well, there is a different perspective, I suppose, on animals. And it was not one I had ever experienced before. And that's the kind of this life-giving structure that is prevalent. It's the most prevalent animal feature on Earth. You know, there's many more eggs than there are adult animals.

So I was kind of like, wow, why has this not been told before? Why has this not been investigated? Why are there? There's loads of stories about the evolution of animals, you know, the familiar, scientific tale of fish taken to the land and evolving into amphibians, reptiles. But actually, eggs have gone through exactly the same kinds of trials and the same forms of adaptation that happened to animal bodies is happening to eggs all the time.

So I guess I saw a window to tell a different kind of cool evolutionary story, I suppose. Yeah, so if you say egg, I bet most people's minds will straight away go to hen's eggs. You know, they're very familiar. But as you go through in the book, eggs come in all different forms. shapes and sizes. So before we get really into the meat of it, is there a strict scientific definition of exactly what an egg is? For me, you know, you can have it in two different ways of describing that, I suppose. So classically, you know, egg is a reproductive structure, a gamete, you know, that propels DNA forwards in time, right? So that is the standard of it, sperm and egg, and that's

very much an animal endeavour. We think that system's been in play for about 600 million years, a really, really long time. But actually, for me, I suppose eggs are sort of time travel devices, I guess, you know, in terms of some eggs are evolved to last only a few days before they hatch out into adults. So I'm thinking particularly of very small, some species of insects. But actually, some eggs take a long time to expose themselves. So the internal egg, you know, the mammal egg famously, you know, with elephants, we're talking about a really long gestation twice as long as a human. So you've got a big, spectrum of egg evolution, I guess, and each one's been tweaked and styled by the environmental conditions by the ecosystem of where that animal kind of lives, I suppose. But, you know, I've been really

semi-careful in this book not to sort of put mammal eggs, you know, this internal egg, within its womb, linked up to mother. I've been really careful not to put that on a pedestal and go, wow, this is a glorious one-off that led to, you know, the importance of us. Because the truth is, you know, placentai, the womb, you know, that's evolved something like 150 times invertebrates alone. Okay, so there's really common little avenue for evolution to explore. So yes, going back to your original question, yeah, eggs, genetic time travel devices. They let animal lineages pass through really tough ecological circumstances. So many eggs survive through famine and drought or seasons, as I say in the book, you know, seasons are very big

an important part in the story of why animals depend upon eggs so often. So let's go right back in time now then. You cover millions and millions and millions of years of evolution in the book. So let's go right to the beginning. What are these sort of evolutionary precursors to eggs? Yeah, that's a great question actually, because for a while, planet Earth was not a place with eggs as we know it. It was a place where animals reproduced by simply budding off. So if you think of some parts of the jellyfish family tree that resemble very much the old-fashioned way of doing it for jellyfish. You know, if you chop off a limb, so if you're a hydra, for instance, this little tiny freshwater anemone that lives in ponds all over the place, you chop off a tentacle, the tentacle

floats away and will grow another body, it will glue to the floor, it will grow new tentacles and a new very simple version of a brain, and off it goes. So by budding animals essentially, no matter who you are, you can just bud off offspring and you would think, wow, what a great strategy, that's brilliant. We think from probably about 700 million years ago, these numbers seem crazy, but we're talking, you know, 500 million years before dinosaurs. This was mostly a jellyfish planet and most animals we think were budding off. So that's looking at a few different fossils that suggest that. And you would think that's great, animals doing really well. And it's almost like this small group of early animals. So think of them as worm-like, think of them as symmetrical on the left

and right-hand side of the body. So bilitarians, just like most animals today. So this little group sections off their eggs very early in development. So in other words, their eggs form in the embryo stage, the eggs form in a defined part of the body, and there they stay. They're not grown later in life. They're there from the very earliest days of that embryo. So these strange animals, for some reason, do incredibly well. It takes them a while, but by the Cambrian explosion, so this is about 550 or so million years ago, this is when all of the major animal lineages sort of sprouted. So, you know, things like crustaceans, vertebrates, mollusks, they all have their foundation in that Cambrian explosion of animals. I argue in the book, you know, that traditionally,

David Attenborough and series like that tell us that the Cambrian explosion was about animals evolving, biting jaws and swimming paddles and suddenly predator and prey relationships, evolution goes into overdrive. I argue in the book, but actually that's probably as much to do with eggs as it is to do with the adult adaptations. So eggs, why does it work? It works essentially because it allows you to mix up genes much better. So if you're mixing up genes and you're mixing up different codes, if you like, you're more likely to hit upon codes that are really successful in those ancient seas. So animals have that kind of built in. And it seems to be in most cases a strategy that animals have never looked back on. So there's only a handful of animals that can regrow their limbs.

Things like newts can grow, hardly newts and salamanders can grow bits of their brain if a fish bites their head off or something like that incredibly. But yeah, most animals, we are mortal, right? Like us, we have one try, if you like, at producing new bodies and it's through the medium of eggs and sperm. So you mentioned there that we're going back hundreds of millions of years. So how do we begin even studying this? That is a great question. There's a really, lot of debate about this because there are some fossils that you find in really old shale. So you have to essentially use lots of chemistry on these very sort of sandy strata, mostly from China.

And these are about one billion years old, so 1,000 million years old. And you find in these fossils, if you break them down, little tiny egg-like structures. And for a long time, scientists argued that these were naturally forming until in the last 10 years, many of these very simple fossilized dots, essentially, you can actually see within them, this is incredible, you can see cells dividing. So there are some of these little egg-like structures that have eight cells, some of them that have 16 cells, some of them that have 32 cells, and you can see evidence of cell division, essentially, the very basics of eggs. So we think that's one of the main bits of evidence we have that this was going on back then, but what did these

animals turn into, there's still loads of debate. So these tiny microscopic egg-like structures, what was coming out of them, the truth is we're still trying to work it out. We think based on evolutionary trees, it was probably jellyfish like animals, but there was some really interesting ones. I actually didn't put them in the book because they need a bit more scientific examination, but they sort of look almost worm-like. So yeah, there's a lot of evidence going back, and even evidence going back maybe 2,000 million years. But again, you know, one of the things that's cool about researching a book like this is you realize there's all these different groups of scientists that you've never even heard of. So these are the palinologist, which means

Latin for dust studies. So these incredible scientists that aren't interested in T-Rex bones, they're actually interested in studying like microscope slides covered in what looks like sand and picking out the things that could or could not be eggs. So yet another group of scientists that I'm in total awe of. Ambition comes in all shapes and sizes. At First Citizens Bank, we roll with your goals because we're built for what you're building. Fit for your ambition for Citizens Bank. Lots of places can expose you to identity theft. Oh no.

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and acoustic engineering, balancing craftsmanship and tradition with pioneering thinking. Name Audio pushes cutting-edge technology to ensure digital precision whilst sustaining Pratt, pace, rhythm and timing, the elusive quality that makes music feel alive and gives it emotional texture. Today, in partnership with French acoustic specialist's focal, name audio creates systems that deliver exceptional sound, an unforgettable listening experience, experiences at home. Try it for yourself at a focal powered by name boutique. Visit focal powered by name.com for more information. So let's change gears a little bit now then. So in terms of reproduction, the egg is sort of only one half of the picture. And one thing that I found really interesting

when I was reading through the book is the different approaches animals take to fertilisation. So could you tell us a bit about that, please? Yeah, I was also very surprised about that as well. So we think of this as like, you know, if you're on land, most animals evolve a penis-like structure to get their sperm nice and close to the egg, which is most often kept within the female's body. So that includes, you know, obviously vertebrates, but also some other animals, including insects as well. They have a little version of a penis as well. And then in the sea, you're like, okay, well, animals in the sea. I've seen it on TV.

You know, they produce these big clouds of eggs. And then, you know, the opposite sex comes over and, you know, sprays their sperm all over it. and you get external fertilisation. But actually, there's absolutely loads of twists, if you like, on those traditional roles we think of as sperm and egg. And the one that stuck with me most of all, actually, is for a period of time, like if you think of those early groups of animals that invaded the land,

you know, 450 million years ago, you've got things like early millipedes, you've got things like early scorpions and mite like animals that later some of them evolved into spiders. And a lot of them are actually, the females evolved to keep the eggs within the body. We think as a way to protect and keep the eggs in a moist environment so that they're not dried out by the sun.

So animals go on land. Females often, the eggs go inside the body. But for a while, males, they invested in spermatophores. So essentially, the male kind of creates an egg-like structure that the female kind of leans on and sort of backs into and puts into her reproductive passageway. And spomatopause, for a while, that was the go-to way to do it on Earth, probably for about 50 million years. The land was sort of dashed, sprinkled with these spomatophanes.

Some of them looked like mushrooms, little tiny mushrooms. Some of them were a bit larger and looked like kind of packets of almost like, have you ever seen Mermaid's Purses as another beautiful egg? So these shark eggs. So they look almost like they're made of cartilage. And scorpions, in fact, still produce these today. They're about the size of a toenail clipping. But yeah, essentially these were put on the land and females walking around, particularly female early mites and scorpions, walking around, sampling all these different spermatophores,

probably eating a few for nutrition, and then selecting the spermatophores that kind of suit them best through perhaps their smells or perhaps their sizes. But, you know, this is, again, that one of the traditional things we think of is, okay, there's always loads of sperm and there's always only a few eggs. But actually, in those days, it was probably that sperm became very sort of less numerous, because if you've got your sperm in a nice little hardy package, you don't need to produce as many, because the female is just going to absorb them anyway. So we think there is certainly some mite species today that have just 50 sperm, sometimes 100 sperm, in a single ejaculation, I suppose. We think for a while this was the way it was on Earth. And that's sort of

what I mean is like we hear these familiar stories of animals and we go, oh, that's one way of doing it, you do this, you do that, bish-back, Bosch. But actually, when we research and, you explore new stories and groups of animals we don't traditionally talk about, like mites or scorpions, you get to expose this whole wonderland, really, of zoological entrepreneurship, let's say. So let's move on to maybe the more familiar kind of egg, like I mentioned to the hen's egg. So when did we first start seeing eggs with these hard shells? Yeah, familiarly, all your listeners will know by now, because we're reminded at least once a week that birds are dinosaurs, right?

So birds are a lineage of the dinosaur family tree that didn't die and that flourished since the end of dinosaurs. So all birds lay eggs with a hard, sort of calcium-rich shell. And looking at fossils of theropod dinosaurs. So basically two-legged dinosaurs, muscular, agile, T-Rex is a theropod, Velociraptor, Theropod, birds also part of that theropod family. So in that group, through fossils, we can be really clear that that group loves calcium-riched. hard-shelled eggs. But, and this was a surprise to me writing it, to be honest, actually there are many groups of dinosaurs that probably didn't have calcium-rich shells. So, you know,

proto-ceratops, though this is a bit like a miniature triceratops. You know, that's famously a group that probably laid shelled eggs that were more like turtle eggs or snake eggs. So they're kind of leathery like parchment. And most often they would have been probably buried because they just don't offer enough protection from the sun. We think for many of those dinosaur groups for which we don't find much evidence of eggs, it's probably because they laid soft eggs that didn't turn into fossils. So yeah, why did Theropod dinosaurs invest in hard eggs? Again, it's yet another kind of mystery, I think, of the age of dinosaurs. One thing I will say is it's a great example of how one little evolutionary adaptation has life history consequences. So

in birds, clearly, these hard-shelled eggs, they take a lot of effort to make, and they take a lot of effort to protect. So in most birds that famously restricts males and females, they have to hang around together, otherwise these valuable chicks are going to die. So essentially, you know, we hear birdsong at the moment. It's so nice to hear. But, you know, birdsong, you know, territories, if you like in birds, that's very much a consequence of this evolutionary adaptation, which is cool. Again, I didn't really think about that. You know, written about birds.

many, many times, and not once have I considered how the egg forced the bird to adapt and vice versa. So sort of sticking with that and adaptations, so these days you see birds eggs with so many different beautiful colours and patterns, you know, what do we know about that? You know, when did that emerge if we even know that? And what purpose does it serve? Yeah, you're right. I mean, there are some really beautiful birds eggs out there. Some have like kind of scribbles on them, almost like someone's used their sort of ink pen,

some are bruised and blushed, like fruit almost, you know. So yeah, it's a great question. And again, for about 200 years, even Darwin and Alfred Russell Wallace were really confused about why is that? Why are birds' eggs? Most eggs are not coloured what's going on with birds' eggs. And, you know, the original hypothesis was that, you know, this is about camouflage. So birds camouflage their eggs. Obviously, that sounds very adaptive. You'd expect, you know, the animals that did that, they're going to spread their genes further because their eggs are going to survive. predators. And then there was another group of scientists that were like, oh, no, no, no, it's because it's about the sun, because it just so happens that birds that lay eggs in dark places,

like kingfishers, for instance, in their burrows, their eggs are often quite boring. So they're like, okay, it's all about protecting eggs from ultraviolet radiation. And loads of competing and combative evidence for both sides. And actually, it's probably to do with something else. And so in the last sort of 50 years or so, scientists who study parasites, who have kind of become a big group. I personally think that the evolution of parasitology about this group of scientists that study parasites has really helped us explain and explore loads of cool stuff about animals.

So anyway, they come along and they're much more like, well, do you know what, maybe there's something else going on here. Birds are very social. As we said, they're very, very territorial, and they are sort of addicted, if you like, evolutionarily, to lay in their eggs. That means there are potential opportunities for the cheeks. right in the birds famously the ones that cheat and there are quite a few most famously for us is the

cuckoo flies all the way over here takes our nests but essentially you know cuckus are really really well adapted at looking for opportunities to sneak one of their eggs into the nest of another bird and this war this evolutionary war has probably been going on for at least 40 million years and essentially the cuckoo sneaks an egg in so that then forces the post bird to find a way, evolutionarily, of course, of spotting which eggs are their own and which eggs are the eggs of parasites which should be removed as quick as possible. And essentially, when birds evolve to colour their eggs or to put patterns on them, it's a way for them to quickly spot which is theirs. But the cuckoos, of course, are also adapting. So they then co-adapt, they co-evolved,

and of course put markings and sprinkles on their own eggs. And that forces the evolution of the host birds to try something different. I would say it's a war of beauty, you know, these colours that you see in bird eggs, they're just absolutely fantastic. It's like art. It's like this self-creating art. And I suppose as long as there will be birds or animals with hard-shelled eggs, we'll see this occur. So yeah, the additional point you raise is a really good one. You know, were dinosaurs who laid hard-shelled eggs? Were they going around, you know, doing this as well? And the answer is we think yes. So I think it's just under 20 different fossil eggshells studied. Two of these compounds that make egg colours are found in them. So yeah, we think even the eggs of Velociraptor, we think was probably a bit

turquoise, a bit like a black bird's egg. So if there was colour in those eggs, it may well be that there was running around amongst populations of dinosaurs at nesting sites. There was the same sort of parasite host relationship, which again, it's really amazing to think of, you know, cuckoos being latecomers to this evolutionary strategy. So yeah, that seems unique to birds, although obviously, mites also have loads of nest parasites. But it's very, very common, I should say, yeah, among birds. So it's not just the cuckoo. Most continents have, you know, 10 or 20 different parasitic birds. So yeah, it's cool, really cool. Yeah, so I promise we'll move on to mammals in a minute. I just have one more question, which is about yokes. So firstly, what exactly is a yoke?

And when did we first start seeing them? Yeah. So I traditionally thought, before going on this big research tour a few years ago that yolk was, you know, pretty much a bird thing, something we see most often in reptiles. So I was kind of like, didn't really appreciate what a widespread feature it is. And essentially yokes very old indeed. So yoke probably, we evolved yoke from an ancestor, all of us, all animals alive today, apart from jellyfish, we've had enough of them, probably evolved yoke about maybe 500 million years ago. So again, this is a kind of Cambrian adaptation Essentially, it is an energy store. So it's a place that provides all of the energy, the nutritional needs of the growing embryo. So essentially, it's a bag of juice and it shrinks as the embryo grows until essentially, eventually, eventually there's almost nothing left.

And that connection where the yolk attaches is nearly always the sort of ventral centre of the body. So the underside of the body. So our belly button is very much an animal condition, you know, on this planet. So yeah, yolk, very nutrient-rich. It contains a lot of the base pairs of DNA as well, sort of in this big swirling soup. So as the animal grows, it can pull upon those resources. And often it's full of carotenoids as well. So this is the stuff that gives yolk that sort of yellow colour. And carotenoids are this special molecule that is very, very good for reducing the amount

of UV damage that the embryo gets. So, and in fact, that also has consequences for animals, because, of course, carotenoids are the things that give a lot of animals, they're beautiful colours. So males, especially in birds, you know, they eat a lot of insects. Insects have a lot of carotenoids. Suddenly they're glowing and they're looking beautiful. This is the same for fish like sticklebacks as well. And they're going around, looking absolutely gorgeous. They're essentially saying, look how many carotenoys I've got. Imagine what our babies would be like, essentially. So let's shift gears again now. And in the book, you have a chapter on the womb. So what do we know about that? How did that come about?

So again, this is a really, really very old structure. It goes back even to, there was a period, we talk about the extinction of dinosaurs, like, well, that's a big event, you know, for this planet. But there is something called the Great Dying that, again, your listeners will know of, so about 252 million years ago, when we had some serious climate change. So, you know, this is the formation of Pangae, this giant landmass. The central regions were just a massive, expansive planetary desert, like in June. and essentially that forced the evolution of different life history strategies.

So back then, a group of early reptiles evolved to keep the eggs inside the body for longer. It might have happened once. To be honest, it could have happened 200 times to 200 different groups back then. My guess is it probably did. But essentially, that was the formation of our branch that later would be given by humans, the name mammals. And that process, even that wasn't simple, you know. So we had different southern continents evolving a kind of strategy of ejecting the embryo at a really early age and sort of propelling it from the reproductive tract, a bit like a maggot, and the maggot crawls up into a different pouch.

And of course, we call those animals marsupials, but when you actually think about it, that is really weird. So we think they actually adapted that from the early mammal condition. So in other words, marsupials are not the primitive condition. We have that condition. We've just retained it. We, you know, mammals that are alive today. But again, that strategy, it sort of sounds easy and many animals have done it, but the difference it makes to the relationship that animals have with their babies is

really, really serious. It's another catastrophic life history change. Because for the first time, mother is still attached to the egg, the embryo. So most animals, this is kind of crazy, but if you think most animals, think of sea urchins, those clouds of eggs drifting around in the sea, and they've been. been fertilised and the females produce them and then it's like, goodbye, offspring, off you go. You've had your yolk, off you go. Actually, that doesn't happen in mammals. It doesn't happen to animals that evolve a placenta. What happens then is that the baby, if you like, the embryo is still connected to the mother and that leaves open a crucial thing. And that is that the embryo can start sort of

evolving techniques to claw as much nutrition from the mother as possible. So with sea urchins, the mother's saying, here is the yoke, that's all I'm giving you. Actually, if those animals, you know, mother and daughter or son are still connected to one another, you can have this evolutionary war which starts to develop where, you know, offspring can evolve to try and take as much as possible from mother. And that thing, I would say, defines very much what is the mammal condition. So in animals with big brains that need a lot of resources, so I'm thinking elephants, I'm thinking apes. I'm thinking, you know, this ape here are humans. Actually, that has a really serious implications. So childbirth is relentlessly hard for our group because the baby is so wanting more all

the time. And even worse than that, the baby is not even fully the mothers, right? The baby is made of both the male DNA and the female DNA. So the male, the dad's DNA is in his interest to have a very needy, hungry embryo. So the female is basically hosting. something that actually genetically is only half hers. So this war, if you like, is crazy. And in humans, I mean, this is the reason we have, you know, periods. Periods are crazy. Menstruation is crazy. It's not something we see in many other animals. But in humans, the placenta, the embryos, placenta is so invasive, it's so grabby that essentially we need these extra thick uterine walls to protect ourselves from the ravages of the unborn, basically. And years ago, I wanted to write a book

about animal menstruation, and I thought it would be a really good thing for us all to start thinking about, because it's incredible, really. And I never got a chance, because I couldn't ever frame it right, but it was a real pleasure in this book to go, actually, this is a natural thing, but it is also extraordinary that this has happened in our lineage, essentially, because we are just such big, brainy apes, I guess. So that's another sort of really clear example of how the evolution of eggs has affected sort of how life functions really. Yeah, yeah, absolutely. And I think obviously the two connect to each other, but I suppose the point of the book is to

remind us that there are, you know, for every animal evolving, there's also, you know, the egg has to evolve as well, and it will evolve clearly as well. And we're seeing that with some species today, you know, with climate change. Many species of insects and birds, clearly, you know, are evolving to lay their eggs earlier. So animals are adapting with their eggs as much as they're adapting through their adult forms. And like I say, it was a real pleasure, really, to tell us slightly different and what feels to me quite a new story, I guess. And, you know, yeah, it's good. It feels good. Yeah, so having said all that, like by way of closing, is there sort of one thing that you wished you could find out when you were researching the book?

But we just don't know yet. Do you know, years ago, honestly, I thought we knew everything. And I would say this is one of the great things about your magazine. I've always thought this is actually there is this real inclination to kind of be like, okay, we're talking about science here. Here are the facts. X, Y, Z. This is why that happens. Let me tell you about this. We know all about that. And actually, in the past, I've fallen foul of thinking like we actually know everything, you know, it's really easy. I think that in school sometimes, you know, the way that we teach science is very much kind of like learn these facts and you get an A or whatever the score is nowadays. I'm so old. But, you know, that's it. You're now a you're on your way, but actually talking about what we don't know is incredibly, incredibly important. Thank you for listening to this episode of Instant Genius, brought to you from the team behind BBC Science Focus. That was Jules Howard. To discover more about the topics we've just discussed, check out his latest book, Infinite Life, a revolutionary story of eggs, evolution and life on earth. If you liked what you just heard, please consider subscribing to Instant Genius on your preferred

platform. The current issue of BBC Science Focus magazine is out now. Pick up a copy wherever you buy your favourite magazines or download a copy on your app store of choice. You can also find us online at sciencefocus.com. This podcast is sponsored by Name, Audio and Focal. The texture and emotional depth of music can be lost through digital sources or poor signal. Name audio believes you can have digital precision with analogue warmth. alongside French acoustic specialist vocal, name creates high-end audio systems combining innovation with craftsmanship

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