Hello, it's your host Andrew here. If you're enjoying Send Me To Sleep so far and you'd like to help support the show, the best way to do that is Send Me To Sleep Premium. Over there you'll get ad-free episodes as well as access to all of our bonus episodes. You can find a link to a 7-day free trial in the description notes. Thanks so much for listening, and here's just a few ads before the show begins. Updating our tariffs to get you our best value, it's a smart tech that helps you take control of your energy future. We're here for whatever's next. Just one of the reasons why we're rated excellent on TrustPilot by our customers. Find out more about how we can help at yournext.com. Eligibility and T's and C's apply. TrustPilot February 2026. Hey, it's Andrew here, and I'm excited to share with you the newest show from Slumber Studios. It's called Sleepy History, and it's exactly what it sounds like. Intriguing stories, people, mysteries and events from history delivered in a supremely calming atmosphere. Explore the legend of El Dorado. See what life was like for Roman gladiators. Uncover the myths and mysteries of Stonehenge. You'll find interesting but relaxing episodes like these on Sleepy History, and the same great production quality you've come to know and love from Send Me to Sleep. So give it a listen, and perhaps you'll have another way to get a good night's rest. Just search Sleepy History in your preferred podcast player. Hey, it's Thomas here. I'm the host of Get Sleepy, another sleep-inducing podcast from the Slumber Studios Network. On Get Sleepy, you'll find hundreds of original bedtime stories and meditations to fall asleep to. Some of our listener favorites are our trips to the rainy day bakery, our Sleepy History series, and our adaptations of classic tales like Beauty and the Beast. Everything is designed with your sleep in mind. So if you're looking for another great way to ease into a restful night's slumber, then just search for Get Sleepy on your favorite podcast player. I'll see you there, my friends. I think you would be forgiven if, when you first looked upon Coral, you believed it to be just some kind of huge underwater rock garden, or naturally occurring arrangement of aquatic plants of some sort. And I know that that's certainly what I thought, honestly, until very recently. I was fortunate enough to visit the London Sea Life Aquarium quite recently with my young son, who very much enjoyed seeing all of the aquatic life that they have on display there. Quite beautiful to see all variety of animals that live under the sea. And what was especially beautiful was their display of coral. And there's something so beautifully mesmerizing about the colors and the patterns and the shapes and the slowly undulating I suppose you might call them tentacles of some of these coral. As they move gently in the water. And looking upon these corals, I honestly am not sure I knew myself precisely what they were, but the immediate instinct or assumption is that they are some kind of rock or plant or perhaps something akin to an underwater mushroom of some kind. And it was only recently that I found out precisely what they were, which is in fact carnivorous animals, which is highly unintuitive. And this is probably why it took people so long to discover that this was the case. We have records of the ancient Greek philosopher and naturalist Pliny the Elder describing coral as a tertian natura, as in a natural third thing, which is a term that he made up because he was unable to distinguish coral as exactly a plant or an animal. And so he put it into this box of third thing as he was unable to categorize it. And it was only much later in the 17th century that William Herschel was able to look microscopically into the matter of these curious formations and see the particular thin cell membranes that are characteristic of animals. And finally deduce that these were in fact microscopic living animals with huge, colorful, skeletons, external skeletons, I suppose you could say, which is what we see as the coral. And another curious giveaway that these life forms are unlike plants, is that they will, unlike many, although not all, plants will respond to touch. So if you poke one, they will recede into themselves, which is very unlike most plants, as I say. But such a curious animal or life form at all to exist. Especially in the fact that they are carnivorous in nature. To look upon a coral reef. It is almost as if to look upon a huge, sprawling city with all its many buildings and fine architecture. And then to discover that the buildings themselves are also the inhabitants. And the idea that these animals are carnivorous is fascinating because you wouldn't presume that they would eat other animals just by looking at them. But they do in fact have these, as far as I understand, almost sort of microscopic harpoons, these little filaments that they will eject from themselves to catch passing plankton or fish larvae. And they are slightly venomous, I believe. And they can drag them towards themselves to consume them. So fascinating and so unlike any other animal that exists on the planet. And now some of these coral, as I say, are purely carnivorous. And they exist in the deepest, darkest areas of the ocean floor. Purely surviving on the sustenance of other animals. But much of the coral that we are familiar with, this beautiful, colorful coral that we might associate with famous reefs like the Great Barrier Reef, for example, are actually capable of sustaining themselves through photosynthesis. Which again sounds incredibly counterintuitive and unlike any other animal that we are familiar with. And when I explain precisely how it is that they do this, it will continue to seem very unique and counterintuitive. But it is microscopic algae that give them this ability to harness the power of the sun for sustenance. And the algae embeds itself into the body, into the structure of the coral. And up to 30% of a coral can be composed of this algae. And it is the algae itself that produces the effect of photosynthesis, taking the light and transforming it into sustenance that the algae then feed off of as well. And so they have this symbiotic relationship in that respect that allow them to be largely sustained by sunlight as well as eating other animals in a carnivorous way. Which again is quite fascinating. If you could imagine another animal that embedded plants into itself and sustained itself that way, crawling along the forest floor with leaves on its back. And only occasionally snatching up a rabbit or a squirrel to keep itself going. But then most of the time sustaining itself, purely from the energy provided by these plants who in turn take it from the sun. It sounds almost like a fantasy, almost like it shouldn't actually be possible to occur, but here we see it in coral. And another fascinating thing about coral is how unfathomably large their structures can be. This sort of huge combined, joined skeleton that they produce. To cover remarkable distances, so the Great Barrier Reef, for example. And I'm not entirely sure whether it is the largest coral reef that exists, it most likely is. But I believe that stretches for over 2,300 kilometers. Which is almost double the length of the United Kingdom itself. Purely coral, stretching all that way. Completely visible from space. Such a remarkable thing. And they're able to do this, of course, in the way that they reproduce. And so, coral are an animal that are capable of reproducing asexually. Which means that much of coral is a clone of itself. But they also go through a process of sexual. Reproduction. Where they will release their eggs or their spawn. Honestly, I'm not entirely sure quite what it is described as. But certain periods of the year, they will release it all at once. Or varieties together. So that they're spawn can intermingle and create new nodes of themselves. I remember reading a very curious, interesting way in which they do this. And now I'm not sure if this applies to all coral. Completely. But I know that some at least reproduce sexually in this way, as I say. Once a year at a very specific time. And this time is triggered by the moon. And in that way is a light sensitive response. Which is a very clever, if you might call it that way, of getting around the fact that coral, in terms of wider senses of the world, have very little in the way of ears or eyes. In any sort of comparable description of what we as human beings have. In order to be able to understand the passing of time. In fact, they have no, like I say, proper nervous system in the way that we would understand it as human beings. To have brains in the way that we do, to have memory, to understand this passing of time. And so they rely on the phases of the moon. And what's curious still is that it is not actually the light of the moon. That they depend upon as their signal for this very particular time that they would release their spawn to reproduce. It is in fact the absence of moonlight and a very specific duration in that absence of moonlight. Which fascinates me very much. So of course as the year progresses and the moon changes its position in the night sky and its phases obviously are accompanied by that. There will be always between night and day a period of total darkness as the moon phases away and the sun begins to rise. And at that time of year where the gap between moon and sun is at its longest. When it has experienced that longest period of darkness, then these coral will learn that is the signal to release their spawn and this is the time that we are to reproduce. Which is utterly fascinating really. Because this in turn implies some ability to understand that that time has passed despite the lack of brain and nervous system and therefore presumably memory. Which has very interesting implications. Perhaps mind boggling implications about the experienced consciousness of such animals. But that would be an entirely different discussion in of itself. But one of the sad things about humans and their constant interruptions of nature is that this very specific, fuzzy, incredibly beautiful process that coral go through. With being so sensitively attuned to the lunar mechanics that go on between the earth and the moon. And always releasing at this very specific time which is predicated on this very specific duration of an absence of light. Is interfered with because of human society unfortunately. Light pollution interferes with this process and is interfering with this process. Meaning that certain stretches of coral are releasing their spawn, their eggs or how we might call it too early or too late. As compared to others. And this can sometimes spell catastrophe because the entire process is dependent upon the coral releasing their spawn at exactly the same time. To maximise the chance of reproduction. Because thousands and thousands of these spawn are released. Just so that and the few of those can take hold and become new elements of the coral. And so if even part of this process becomes interrupted or staggered in that way. Then the entire process falls apart. And this is of course something that human beings or those human beings who understand the importance of these coral reefs and and care enough to do something about it. And something that these people are desperately trying to counteract in order to save coral reefs. And of course when we talk about coral. Light pollution is not the only human interference that will often crop up. In fact light pollution is it's not something that many people really know about as as a problem that is facing corals it is mostly that of climate change. And the way in which human beings are disrupting our climate that is affecting coral. And in researching for talking about the subject of coral. I found out a little bit more about specifically what it is that's going on to coral as a result of this ocean temperature change and the increased acidity of water due to pollution. And it is this algae that I spoke of before. The algae that embeds itself and produces photosynthesis for the coral. And also gives the coral its beautiful colors. When the coral is stressed because of this temperature change and the acidity. It begins to eject this algae from its structure. And this has two side effects. One it begins to lose its color. And becomes white and chalky in appearance. Which is I suppose what you could call the natural or underlying appearance of coral in reality. And this is what is referred to as coral bleaching. And of course this means that not only has the coral lost its color in ejecting this algae. But it has also lost a vital source of its nourishment. And so this can have catastrophic effects on the coral reefs themselves. And what conservationists are attempting to do is farm coral itself. And by farm I don't mean harvest. Although that is something I've read that we as humans have done in history. And I wonder if we had known the great importance of coral reefs to the overall ecosystem of the ocean. And therefore of the planet itself whether we would have abused coral reefs. As much as we did I presume we wouldn't. But that's something humanity is still struggling with today to truly understand. But I do know that the coral was used in medicine crushed up. And given as medicine for ailments. And also in periods of history harvested in great quantities. As fine jewelry. What we used for fine jewelry. Which feels like a very typically belligerent and obtuse thing. For humans of antiquity and perhaps even humans of today to be getting on with. But like I say not farming in this respect but I suppose to use a more evocative and perhaps accurate word. Cultivating coral. And producing or inciting stimulating reproduction in a lab setting in a man made farm setting I suppose. To help it grow and proliferate. And then what these farmers or I suppose I should say scientists are then able to do is take these healthy controlled growth corals and graft them onto existing corals. In areas that are at least a present. More tolerant to the changing environment of the ocean in temperature and ascesity. And this is one way in which scientists are hoping to combat the effects of climate change. And then another is again quite a strange unintuitive way in that. Coral much like we have a gut biome in ourselves in our stomach we have this biome of microbes that live and thrive within our digestive system that is unique to us and also vitally important to our health in general. Corals coral systems have biomes of their own. They are also made up of thousands of microorganisms microbes that that support the health of the coral and are vital to their overall well-being. And so the idea is that coral reefs could in some way perhaps be inoculated with probiotics. And that would help strengthen them against the effects of climate change. Which is so fascinating and unintuitive. But a very clever idea as well. And gives me some hope to hear things like this. To know that people far more knowledgeable and clever than I are working diligently at the problem of coral reefs being affected in this way. And finding remarkable and ingenious solutions. And as long as these people are given the support that they need. And the people of the world continue to understand the importance of these coral reefs. Then I have hope that they will continue to flourish. And my immediate thought whenever I think of coral is the Pixar movie Finding Nemo. And the image of Nemo and his father Merle poking their heads out of the anemone. That they live inside of. And I think that is my immediate thought because it might have actually been the most vivid representation of a coral reef. That I had first seen. I am not sure I had much knowledge or interaction with the idea of a coral reef. Perhaps I had seen it briefly in books or on television screens in other ways. But to have it narrativised in that way. Was profound because you then began to understand that the thing that you are looking at. There this like I say upon first sight just appears to be a beautiful underwater rock garden that is perhaps lovely to look at but perhaps intuitively just inert in some way. Beautiful but pointless one might think. To see it in a film. Like that and to see that the main characters are living inside of it. You begin to understand its true importance that in fact. These coral reefs are a part of a larger ecosystem of so many living things under the water. And how it is their home and it is their source of food. And in some sense I suppose you could say their source of community. If you could attribute such a thing to marine life which I believe you can. Absolutely. I'm sure marine biologists might have a more measured and ambiguous take on that but it is my opinion that if fish swim in schools then they almost certainly after some form of community. And so I think Pixar did a wonderful thing in representing coral reefs and the ocean. In that beautiful wholesome way that makes it appear as a magical world. That we rarely are privy to. And I have absolutely no doubt that. Many people who are working into careers of marine biology. Or perhaps already in established careers or in some form of conservation. Were inspired by that film. It certainly inspired me. And if not in a way that made me directly go out and. Dedicate my life to conservation of the life in the ocean. It at least gave me an awareness. That this life under the sea. Is remarkable. It's unique. It's special. And it's vital that I be protected.
