Megalodon

As part of our week of Sharks on the Ancients, today we tell the story of Megalodon, the largest living marine animal, ever. Does this colossal prehistoric shark still lurk beneath the waves? Tristan Hughes is joined by leading expert Professor John Long to unveil the jaw-dropping size, power, and ferocity of this ancient super-predator. John recounts his incredible fossil discoveries which chart evolutionary milestones, and reveals the mind-blowing hunting strategies of Megalodon. MORE Prehistoric Ireland: Newgrange https://shows.acast.com/the-ancients/episodes/prehistoric-ireland-newgrange Woolly Mammoths https://open.spotify.com/episode/2CqmGAaFfqm2yFFsSHXpsX Presented by Tristan Hughes. Audio editor is Aidan Lonergan, the senior producer is Anne-Marie Luff. All music courtesy of Epidemic Sounds The Ancients is a History Hit podcast. LIVE SHOW: Buy tickets for The Ancients at the London Podcast Festival here: https://www.kingsplace.co.uk/whats-on/words/the-ancients-2/ Sign up to History Hit for hundreds of hours of original documentaries, with a new release every week and ad-free podcasts. Sign up at https://www.historyhit.com/subscribe. You can take part in our listener survey here https://insights.historyhit.com/history-hit-podcast-always-on: https://insights.historyhit.com/history-hit-podcast-always-on Hosted on Acast. See acast.com/privacy https://acast.com/privacy for more information.

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

• 0:00Tristan Hughes?

  Ever wondered why the Romans were defeated in the Teutoburg Forest? What secrets lie buried in prehistoric Ireland? Or what made Alexander truly great? With a subscription to History Hit, you can explore our ancient past alongside the world's leading historians and archaeologists. You'll also unlock hundreds of hours of original documentaries with a brand new release every single week, covering everything from the ancient world to World War II. Just visit historyhit.com/subscribe.

• 0:31Tristan Hughes?

  Hey guys, I hope you're doing well. I'm all good here. I'm currently relaxing in my local park this lovely summer's evening in London. And to tell you about today's episode, I'm really excited to share this one with you because we are continuing our special week of episodes on prehistoric sharks, finishing it off with this episode about the biggest, the meanest, the baddest prehistoric shark of all: the real-life Meg, the real Megalodon. I loved learning about what the archaeology is revealing about this super predator of prehistoric seas. Our guest once again is the leading prehistoric shark expert Professor John Long. Now let's get into it.

• 1:24Tristan Hughes?

  It is one of the most famous predators of all the time: the apex prehistoric shark that has fascinated humans for over a thousand years, and continues to do so thanks to movies and museums today: Megalodon, which lived between roughly 23 and 3 million years ago. In our previous episode, we explored just how diverse and successful sharks became hundreds of millions of years ago. Now we're going much further forward in time and exploring the story of the real Meg: the largest shark to ever live, and the most fearsome, the greatest predator of all the time.

• 2:06Tristan Hughes?

  This is the story of Megalodon, with our returning guest, Professor John Long.

• 2:14Tristan Hughes?

  John, welcome back. It's great to have you back on The Ancients.

• 2:17Speaker 01

  Thanks Tristan. I'm really pleased to be here.

• 2:20Tristan Hughes?

  Now, we're doing this from two parts of the world, very different parts of the world, me in the UK, yourself in Australia. It's the morning here, I've got my cup of tea, it's the evening there, and you've got a beer if I'm not mistaken.

• 2:31Speaker 01

  I do indeed.

• 2:32Tristan Hughes?

  Fantastic, that is the way to do it. Last time we covered the rise of sharks, but today it almost feels like we're covering the shark of all sharks, the megalodon. Now, was this one of, if not the greatest predator of all time?

• 2:46Speaker 01

  I think it is the greatest predator of all time. There's no dinosaur that ever comes close to megalodon in terms of size and sheer bite force and ability to be a carnivore.

• 2:56Tristan Hughes?

  And what first got you very interested in the story of megalodon in particular? I know in the last chat you mentioned how you started, you know, looking at fossils when you were seven years old. Did megalodon come soon after that?

• 3:10Speaker 01

  Yes, well, I was always trying to find a megalodon tooth. It was the prize we all sought after, the buried treasure. But I found hundreds of different types of fossils, shark's teeth, but I only ever found one megalodon tooth, but it was a half, it was a broken one. So it was always something that eluded me, but I've got one now. I actually purchased a, this is a big megalodon tooth, the size of my hand, from North America. And it's a beautiful example. I love to bring it along to show groups when I give talks on sharks.

• 3:39Tristan Hughes?

  And can you give us a sense of the size of just that one megalodon tooth?

• 3:44Speaker 01

  Yeah, well, this one's a good 13 centimetres in length, and it's got serrated edges. It's a big triangular tooth, and it's quite massively thick and heavy. So the largest megalodon teeth are up to 18 centimetres in height. So they're coming from the jaws of a shark that would have been at least five or six feet or two metres across, that sort of size. You know, undoubtedly the biggest predator that Earth has ever seen. Now, it was a gigantic shark, we know that, but what it looked like, we'll get into that later. I think first we've got to go back to the origins of the megalodon story.

• 4:21Tristan Hughes?

  Let's explore that because we finished our last chat at the height of the dinosaur period in the Jurassic period, having covered most of the chat being on the first golden age of sharks before the rise of dinosaurs. But can you almost bridge that gap between the Jurassic and the time of the dinosaurs and the rise of megalodon? Because it feels that there's quite a few million years in between.

• 4:43Speaker 01

  Yeah. Well, in the Jurassic, say we go back 150 million years ago, there's a wonderful fossil site in Germany called Solenhofen. It's where archaeopteryx, the first bird comes from, that's, you know, feathered dinosaur. And we also get sharks in those same deposits that are beautifully preserved, whole, complete specimens, really the best preserved sharks you can, you can see from anywhere of that age. And these include the first modern sharks, sharks that are the same genus as living sharks, like the bullhead shark or the horn shark, heterodontis, the poor Jackson shark, we call it in Australia. And we've got other members of the first wabi gongs, or the first angel sharks. But the group that was the most abundant from the late Jurassic,

• 5:26Speaker 01

  the early Cretaceous onwards, is the group of sharks we call the lamina forms. Now lamina forms today include the white sharks, the mako sharks, the thresher sharks. And this was the group that really took off in the Cretaceous period, the last part of the Mesozoic era. And it's when sharks suddenly got large again, from being very small after the great dying, we get about 100 million years ago, in the middle of the Cretaceous, sharks that suddenly reached seven, eight metres in length. And they're very big lamina forms related to the modern sand tiger sharks, like the grey nurse shark. They're not related to the white shark because that lineage hasn't evolved yet. But they're part of that family called the lamina

• 6:10Speaker 01

  forms. And there are over 100 different species of these lamina forms living in the Cretaceous seas of the world, which was from about 145 million years ago to about 66 million years ago, the end of the age of dinosaurs. Of course, they weren't alone in the seas. There were gigantic marine reptiles they had to fend themselves against, such as the giant mosasaurs, giant lizards that developed paddles, some of them up to 20 metres in length, that appeared towards the end of that period. And the sharks of the day then actually got smaller and they got got down to about five or six metres. But I I have to mention one or two sharks that were really spectacular during

• 6:51Speaker 01

  the seas of this day. One of them was called Tykodus and it had huge domed crushing toothplates. Now, for centuries, all we had was teeth of this beast and nobody knew what it was. Many of the scientists said, oh, it has to be a stingray, a giant ray, because rays had evolved in the Jurassic as well. So that's another lineage of sharks that split off from the modern ones to become the stingrays of today. They they appear in the Jurassic period. Anyway, back to Tykodus. Bits of its jaw were found in Kansas and parts of North America, and they could reconstruct that this thing was gigantic, probably up to 10 metres in length. But still, with only teeth and bits of jaws, we knew nothing what it was like. And just as my book was going to press in

• 7:36Speaker 01

  last year, being printed, a paper came out where they discovered a deposit in Mexico with whole complete skeletons of Tykodus preserved, with all the teeth in the mouth, the fins, the tail, the body, everything. And they discovered it was nothing like a stingray. It was actually a laminaform that would have looked something like a white shark with a really sharp streamlined body. This was a fast swimming creature, like a predator, but not with sharp teeth, but with crushing teeth. So what did it eat? Well, the theory is that probably it was hunting these giant turtles that were in the seas of the time, and also very big ammonites or squid-like creatures, some of which grew to two metres in diameter in the seas of the Cretaceous. So a fast swimming

• 8:20Speaker 01

  predator that preyed on crushing its prey to death rather than killing it with sharp pointed teeth. What an amazing beast.

• 8:28Tristan Hughes?

  That is still the time of the Cretaceous, is it? Where you've still got T. rex and the like, well, at the end of the Cretaceous.

• 8:33Speaker 01

  Exactly right. T. rex on land and and giant triceratops and things, but the seas at the time were dominated by the giant predatory reptiles like the mosasaurs, which were way bigger than any sharks of the time, and the rise of these laminaform sharks. There were also other members of living shark families, but I won't go into all of them because it would we'd be here all night. But we'll just concentrate on the laminaforms because they're the ones that are going to give rise to megalodon. So sixty six million years ago, what happens? If you're a dinosaur and you looked up, you would have seen a terrifying sight as a big star gets bigger and bigger and bigger. And then bang, crashes into the earth, causing a devastating mass extinction event sixty six point four million years ago.

• 9:16Speaker 01

  And this affected not only life on land, but life in the oceans. So in the seas, these giant marine reptiles go extinct, as do the big ammonites, the big coily squid-like creatures. Some of the lineages of sharks go extinct, but most of the main groups pass through that boundary. But they have to recover from being knocked for six, shall we say, that smaller numbers of species are left alive, they have to recover. So in this new age called the Cenozoic Era, which goes from sixty six million years up to the present day. We find that the seas are fairly benign. There are small sharks and one big predator emerges called Otodus obliquus. Now, it doesn't have a common name.

• 10:00Speaker 01

  Megalodon has a binomial name, it's called a Otodus Megalodon, but we all just call it Megalodon. But this is the same genus, like Homo for man, Homo sapiens, Homo neanderthalensis. So we have an early relative of Megalodon called Otodus obliquus, which got to about maybe seven to eight metres in length. And probably preyed mostly on fish. We know this because there wasn't really much else it could have eaten. There were no whales in the ocean at that time. Just a few giant penguins were starting to emerge. Penguins about two metres high in the southern latitudes that they could have fed on, but there were also large billfish and swordfish around that these Otodus probably preyed on.

• 10:42Tristan Hughes?

  It's so interesting, isn't it? We're almost kind of following the line until you get to the Meg, until you get to Megalodon. But it's also interesting, John, how much people like yourself know about the evolutionary line of Megalodon. It sounds like a lot of work's gone into that.

• 10:57Speaker 01

  Yeah, well, I actually took a lot of my evidence for this from a truly remarkable British.

• 11:04Speaker 01

  Paleontologist called David Ward, who lives in Orpington. And David is a vet, actually, he's never trained as a paleontologist. But he was able to set up a successful surgery, veterinary surgery franchise. So he could then spend a lot of his time chasing fossil shark's teeth. And he's written over a hundred scientific papers and named ninety new species of fossils. So he's quite an expert in it now. And he wanted to go searching for the source of the Megalodon lineage. And for a paleontologist, this is like the old explorers finding the source of the Nile, you know, in Africa.

• 11:37Tristan Hughes?

  Eldorado or something, yes.

• 11:38Speaker 01

  Mystery, you know, when did the the Otodus obliquus that appeared after the dinosaurs first start getting bigger and suddenly there was a change in its teeth? Because it had sharp, cutting edge type of teeth, triangular teeth, but not the serrated edge teeth that Megalodon has. Somewhere in that evolutionary lineage, we're looking for a point in time where they developed serrations on those teeth and then they get bigger and bigger and bigger. So what did David do? Well, back in the early nineteen nineties, he was working with some colleagues in Kazakhstan. And this is after the collapse of Soviet Russia kind of thing. And the only way to get to the deserts of Kazakhstan was to tee up with the local scientist over there that had these old worn down trucks.

• 12:23Speaker 01

  And they didn't have any modern equipment. He said it was one of one of the most sort of rough and ragged expeditions he'd ever been on. They got lost several times because they didn't even have proper maps. They just had sketch notebooks with landmarks to look for, like a tree or a sort of mouth of a river, turn left kind of thing. So after three or four days in the deserts of Kazakhstan with these fellow colleagues from Russia, he ended up getting to the site where those Russian scientists years before had found a mixture of teeth, some of them serrated and some of them straight edged. And the question was, were these teeth all from the same layer? Or did they come from different layers, giving a sequence of age?

• 13:06Speaker 01

  And with a lot of careful digging and mapping out the the layers inch by inch by inch, he was able to ascertain that the lowest layers had these sharp pointed teeth without serrations. And then the layers above it, the serrations were just beginning to show along the edges, very fine crenulations. And then the layer above, he had teeth that were slightly bigger, but with sharp, well-defined serrations along the edges. And that defines a new species that was the beginning of the lineage leading directly to the megalodon.

• 13:39Tristan Hughes?

  Wow. There's also something extraordinary in the fact that those people, they had to go to Kazakhstan, to the great steppe and the deserts of Kazakhstan, to find these shark teeth from millions of years ago. But I'm guessing that also hints at how the the geography was very different back then.

• 13:55Speaker 01

  That's right. This was a desert, but it was below the sea at that time, shallow seaways. But the point is that you can find megalodon teeth and shark teeth all around the world. But it's rare to find an outcrop of layers of rock that give you a nice stratigraphy of several layers that give you a block of time where you can see an evolutionary change. So this block of time we're looking at was an outcrop of about five or six metres that covered four million years of time from about fifty two million years ago to forty eight million years ago. And these are well dated by the microfossils in those layers that are dated elsewhere with radiometric dates on volcanic rocks and so on.

• 14:38Speaker 01

  I explained it quite clearly in the book, if you want the the full explanation. But going back to what David found, by digging layer by layer by layer, he saw the transition going from the Otodus obliquus to this new species called Otodus axuaticus, which had the definite serrations. But it still had these little side cusps on the teeth that the Otodus obliquus had. Next, we get those teeth getting bigger and going into another species that's pre-Megalodon, and then much, much bigger teeth where they lose those little side cusps and then you've got true Megalodon. So what drove this sudden increase in size? Yes. Well, the answer in evolution is always resources.

• 15:20Speaker 01

  And what was the new resource that came into the ocean at that time? Well, precisely at that time, forty-eight million years ago, guess what? First whales appeared in the ocean. They were pretty small, but within a few million years, they got gigantic really quickly, up to twenty metres in length, things like basilosaurus. And we believe this was an arms race. Predator prey, the prey gets bigger, the predator gets bigger. And when whales like that provide a rich source of energy, blubber, high-fat content food, sharks can then get a lot more energy from their prey than just by eating fish or other turtles and things like that.

• 16:03Speaker 01

  So, within a few million, ten millions of years, not, not, we're talking from forty-eight million years ago to about twenty million years ago, so we're talking over twenty-eight million years. We see this gradual increase in the size of these teeth and the gradual expansion of the teeth get broader and they lose those little side cusps as they develop into one big gigantic triangular tooth and that's the beginning of Megalodon.

• 16:38Speaker 02

  Are you looking for the perfect podcasts to hunker down with during the longer, colder, darker nights?

• 16:44Speaker 03

  Well, look no further than the award-winning After Dark: Myths, Misdeeds and the Paranormal with me, Maddie Pelling.

• 16:50Speaker 02

  And me, Anthony Delaney. We are historians and love all things gloomy and macabre.

• 16:56Speaker 03

  From Tudor executioners and ancient Egyptian death rituals to witch trials and folklore, feel transported back in time on After Dark. Out every Monday and Thursday, wherever you get your podcasts.

• 17:08Speaker 02

  And guess what? We're also now on YouTube. After Dark, a podcast from History Hit.

• 17:27Tristan Hughes?

  So the true megalodons, do they only emerge some roughly than 20 million years ago? Almost the climax of this arms race?

• 17:35Speaker 01

  That's exactly right. You know, we can, we can see jumps in the teeth that go from one morphotype to another, and that defines the different species of the Otodus, Otodus angustidens, Otodus auriculatus, and then Otodus sort of megalodon, these are the different species. Auriculatus came first, and then angustidens, and then megalodon. So let's talk about megalodon. It appeared about 23 million years ago, and it died out about 3 million years ago. We'll talk about its extinction later. But most people think we only know about megalodon from its teeth, but they're wrong. We actually have a number of specimens that show associated remains of megalodons, like associated teeth that

• 18:18Speaker 01

  occur with scales and bits of cartilage. We also have one skeleton of megalodon in one of the natural history museums in Belgium, and it's got like 140 vertebral discs that were articulated, but it's missing the head, so we don't have the teeth. We know it's megalodon because it's a laminiform shark vertebrae, which has calcified vertebrae, just like modern white sharks, and it's gigantic, and there's nothing else in the seas at that time that big, so it simply has to be megalodon. This is interesting because up until the discovery, well, this thing was found a long time ago, but very few people had studied it. But up until a recent new study was made of those vertebrae,

• 19:03Speaker 01

  the shape of megalodon was always by default taken to be like a big gnarly white shark on steroids.

• 19:10Tristan Hughes?

  Yes.

• 19:10Speaker 01

  And you've probably seen the Meg, you know, Jason Sivan kills everything and saves the world. Well, fundamentally, every megalodon B-grade movie ever made restores it as a white shark, simply because in the olden days, paleontologists believed megalodon was the ancestor to the white shark. But now we know that's not the case at all. It's a completely separate set of lineages.

• 19:35Tristan Hughes?

  So what do we think then that Megalodon actually looks like? What do we think was the body structure of Megalodon? From its teeth and its head to its fin, to its tail, I mean, everything?

• 19:46Speaker 01

  We think it was a lot more slender than the restorations that make it like a big white shark. We know this because a recent paper was published only late last year that studied that vertebral column from Belgium. And they realised that the tail vertebrae have a slightly different shape to the rest of the body vertebrae. So denotes where the tail begins. And the tail was much larger and longer than we thought, so the body was more elongated. So this means that Megalodon was probably way bigger than we thought it was previously. Probably up to 24 or 25 metres in length, but more slender of built, like not as massively chunky.

• 20:25Speaker 01

  Maybe like a nurse shark or a slender type of sand shark type of body shape. And there's further evidence that backs up that it wasn't as fast as we might have thought. The scales, scales of sharks are really, really important. They might be tiny, but they have little riblets on the surface. And that breaks the tension of the water. And the fastest swimming sharks today, like Makos, have a very particular kind of scale with three ribs. And they can actually bristle those scales up from the skin when they want a super burst of power, speed to go faster. So studies of the scales of Megalodon combined with the body

• 21:06Speaker 01

  indicate it probably had a slower swimming speed than the the modern white shark, something like two kilometres an hour. But it was still capable of fast prey attacks, you know, because it had a big, long, powerful tail. And it would have been able to still catch whales. Clearly it did. We know this for a fact. We're not guessing here because we find fossil whale vertebrae with Megalodon teeth stuck in them.

• 21:28Tristan Hughes?

  Wow.

• 21:29Speaker 01

  Or remains of other mammals with Megalodon scar marks cut into them, quite distinctive.

• 21:34Tristan Hughes?

  Well, you've kind of hinted at it there with that surviving remarkable evidence of Megalodon teeth in whales. Do we know then just how powerful and devastating, you know, rows of Megalodon teeth would have been, even to the biggest whales at the time?

• 21:48Speaker 01

  Exactly, and studies have been done on the bite force of megalodon teeth, you know, based on finite element analysis, reconstructing the jaw musculature, which is not hard to do because all the laminiform sharks have the same kind of architecture around the jaws of those muscles, so it's pretty easy to reconstruct a jaw and guess where the muscles attached and so on. So it had a very powerful bite force. We know from certain fossil remains that megalodon could have attacked whales from head on, not necessarily chasing them and biting them from the back, you know. So it was an ambush predator, it would have had different ways of catching its prey. We know white sharks today often ambush their

• 22:29Speaker 01

  prey by hiding in deep water and coming straight up, you know, to catch seals. Maybe megalodon did that as well. Whatever it did, we don't know exactly how it caught its prey, but it was successful because meg teeth are found all around the world in deposits between three and twenty-three million years ago. But one thing we do know about meg is there's been some remarkable people studying megalodon, and one of them is my hero, I call her the queen of the megalodons, Professor Catalita Pimiento, is at the University of Zurich and also at Plymouth, she's got joint positions. And she's the only person in the world I know that's done two postgraduate degrees just on megalodon, she's had a master's and a PhD. And she grew up in Bogota in Colombia during a time of bombings and kidnappings

• 23:14Speaker 01

  and lots of crime, and she's kept her head low and studied at university and eventually went to America to do a PhD and studied megalodon. And from her remarkable work, we know things like that the average size of megalodon was more like twelve to thirteen metres for the average population, that the big ones that we talk about that were gigantic are the extreme size ranges. It's kind of like, you pick any shark species today, the average size is pretty much smaller than you would imagine. The average size of a white shark is between three point five and four metres, females to male. Hmm. But we always think of the big six metre ones that are, you know, humongously big.

• 23:56Speaker 01

  So Catalina also discovered things like the the birth size of based on the teeth that they probably gave birth to two and a half metre long young pups and things like that. And she discovered that and recently, not her work, but a team that looked at isotopic ratios in the teeth, discovered they were warm blooded, that they had a body temperature of 28 degrees Celsius. This is a new technique called clumped paleo isotope thermometry, where we look at the temperature that the cartilage bonds form in living animals like sharks or reptiles or whatever. And then we apply it to the fossil record to look at the same ratios of isotopes to calculate that temperature. It's how we first calculated that dinosaurs were warm blooded, by real evidence, not by speculation.

• 24:41Tristan Hughes?

  And is there also the fact that the fin of the megalodon was bigger or just as big as an adult male, as like a six foot male today?

• 24:50Speaker 01

  We can only speculate on the size of the fin. And you have to, I mean, when we've got nothing but a vertebral column and scales and teeth, then the rest of it has to be fleshed out by analogy with living sharks. So it depends on which shark model we're using. If we're using a white shark, then the fin might be quite high. But if we're using a nurse shark, it might be a little bit lower. So I wouldn't like to speculate on the exact size of the fin. It's nothing we'd have any real evidence about at this time.

• 25:19Tristan Hughes?

  You mentioned how megalodon remains have been found across the world. Can you give us a sense of the world that they lived in some 23 million years ago? So of course you've got megalodon in the seas, you've got these great whales as well. But what did the earth look like both above the waves and beneath the waves at that time?

• 25:37Speaker 01

  Okay, well, that's a good question because 20 million years ago, the current position of the continents wasn't very different from where they are today. You know, there's not much change really. Australia's a little bit further south and so on. The oceans were much the same as they are today, but we had a lot higher abundance of whales, baleen whales in particular, a lot more species than we have today, and bigger biomass in the oceans. So a lot more mega faunal creatures, bigger creatures like larger turtles, gigantic seabirds up to six metre wingspans with beaks covered in horny teeth. Things Pelagornis, which was a large predatory seabird. We had lots of manatees and giant dugong-like creatures, seals as well.

• 26:21Speaker 01

  Walruses with strange tusks coming out everywhere. So the seas were full of a lot of food for Megalodon. But also a lot of other predatory sharks that were competing for the same resources. White sharks hadn't appeared at that time. They appeared much later, towards the end of Megalodon's reign. But take some of the other laminiform sharks that are alive today, like we have, for example, Mako sharks. We had gigantic Mako sharks that, like this tooth I'm holding, that I found as a kid from Bo Morris. Now, that's a tooth that's about six centimetres in height. And yet, these Mako sharks were probably getting up to eight to nine metres in length.

• 27:01Speaker 01

  And now we call them Cacarodon hastalus, different species but the same genus as the living white shark. And they would give rise to the modern white sharks later on, just by the same mechanism, developing serrations on those big teeth. Think of thresher sharks, you know, thresher sharks with the gigantic long tail?

• 27:19Tristan Hughes?

  Okay, yeah.

• 27:20Speaker 01

  Well, we had gigantic predatory thresher sharks that had big, robust teeth with serrations on them. No living thresher shark has serrated teeth, but these are occupying the same niche as, say, white sharks would have today. Again, targeting marine mammals. We had gigantic tiger sharks, getting up to eight metres in length. I mean, you name it, whatever was around today, we had a bigger version of it back then. Because there was so much more biomass in the oceans. The food chains were on steroids, so, you know, we expect a lot more predators. So it was a very interesting world, and for Megalodon to emerge as the top apex predator of this predator-rich ocean was really quite, you know, quite an amazing moment in evolution.

• 28:13Tristan Hughes?

  Are you looking for the perfect podcasts to hunker down with during the longer, colder, darker nights?

• 28:19Speaker 03

  Well, look no further than the award-winning After Dark: Myths, Misdeeds and the Paranormal. With me, Maddie Pelling.

• 28:26Tristan Hughes?

  And me, Anthony Delaney. We are historians and love all things gloomy and macabre.

• 28:31Speaker 03

  From Tudor executioners and ancient Egyptian death rituals to witch trials and folklore, feel transported back in time on After Dark. Out every Monday and Thursday, wherever you get your podcasts.

• 28:43Tristan Hughes?

  And guess what? We're also now on YouTube. After Dark, a podcast from History Hit.

• 29:03Tristan Hughes?

  With Megalodon being the top apex predator and hunting things like whales, but of course you also have those other massive marine mammals as well, like those other sharks. Do we get a sense that Megalodon would have also eaten those other sharks too? And other sea creatures alongside whales?

• 29:21Speaker 01

  Yeah, I mean sharks are not fussy eaters. They'll eat whatever they can catch. Generally, if other sharks are around, they'll have a way of avoiding big predators and, you know, just get eaten if they're ill or opportunistically caught, you know? But Megalodon would have targeting, the isotopic work that's been published recently by Jack Cooper and other people have shown that they had a very high fatty diet, you know, based on the isotopes. So they would have primarily been targeting marine mammals and even large turtles and other large seabirds and things like that, but mostly marine mammals, because that's the richest source of energy you can get.

• 29:58Tristan Hughes?

  Now, naturally, as you mentioned earlier, like this is the the super hunter, like the super predator of all times and the Megalodon. How unique, aside from its kind of size and power, John, how unique would you say that Megalodon is in its structure compared to both sharks more ancient than it and modern sharks today?

• 30:20Speaker 01

  In terms of its size, we're talking up to 24 metres in length and maybe weighing up to 70 tonnes in weight. Bigger than any shark, it's every bigger than any fish or any other shark or any other marine creature that's ever existed in the ocean. That's it. Bigger than the mosasaurus, bigger than any of the marine reptiles. Not as big as the blue whale or the large baleen whales. Even some of the sperm whales today would have been probably approaching the same body size and mass as megalodon. But they're a different kind of predator. They're not a super predator. What I call as a super predator is something that has teeth adapted for killing prey equally its own size or larger.

• 31:03Speaker 01

  And that's where big serrated teeth means you can attack a large whale and bring it down and eat it. Even a white shark can bring down a humpback whale. And, you know, I give an example of that in my book, how they do it in a very clever way. So that's a super predator, something that can kill something bigger than itself or attack something its own body mass. Megalodon was certainly in that category, but not sperm whales because sperm whales tend to hunt squid. And things that are still large, but nowhere near their own body size or body mass.

• 31:31Tristan Hughes?

  Apologies, apart from size, just like in in the body adaptations and the structure, because as we've mentioned already. Yes, the size of megalodon was like unlike any other shark. But was it unique, just kind of going back to this before we move on to the Alfred extinction of the megalodon. Do we get a sense that there were certain parts of its body adaptations and its structure? That really sets it apart from both more ancient and more modern sharks today.

• 31:55Speaker 01

  Apart from its size and the fact that it was a warm blooded, like some other living laminforms are warm blooded, but a body temperature of 28 Celsius. Means it was able to forage much further in range than than other sharks of its day, apart from maybe some of the other warm blooded laminforms that were closely related. I think it's just power of its bite, you know.

• 32:15Tristan Hughes?

  Right.

• 32:16Speaker 01

  Most powerful bite force of any creature. So that's the business end of a megalodon, very powerful, large teeth, the very powerful jaws to to inflict that bite, that killer bite.

• 32:27Tristan Hughes?

  John, it's absolutely extraordinary. For how many millions of years do megalodons reign supreme in the oceans?

• 32:33Speaker 01

  About 20 million years. And then towards the end of that period, we come across a minor mass extinction event. It's called a end of Pleistocene megafaunal marine extinction event. And about 2.6 million years ago marks the end of the Pleistocene period. You know, it's not that long ago really, compared to the whole history of sharks. But the ocean started cooling at that point. And it's the beginning of the Ice Ages, where we get, you know, a succession of seven Ice Ages going into the Pleistocene period. And the ocean's cool, suddenly the food chain is altered, there's not enough resources around, many of the whales and marine megafauna go extinct, and megalodon just couldn't cope.

• 33:15Speaker 01

  And at that stage, the white shark had appeared about five to six million years ago, the modern white shark, that is, we had some ancestral ones before that. And they kind of took over the niche of megalodon, eating, you know, preying on whales and seals and marine mammals and so on.

• 33:31Tristan Hughes?

  And do we think it is very much climate that brings to an end the reign of the megalodon in the seas?

• 33:36Speaker 01

  We do. Because if megalodon just went extinct by itself, it would be a mystery. But the fact we have a marine megafaunal extinction event with many other species of both giant turtle, whales, and even other large sharks, like the giant Mako shark that I just showed you before, that, you know, we have other sharks going extinct as well. So it's a whole decline of predators going extinct at that time, and other large creatures that couldn't get enough resources to survive.

• 34:06Tristan Hughes?

  I mean, John, it's astonishing, given our last chat where we covered sharks some 400 million years, 300 million years ago in the Devonian and Carboniferous, the fact that we're now down at some 3.5 million years ago with the extinction of the megalodon. You know, that's the same time then you've got early humans like, well, early on the human line, like Australopithecus in Africa. And I don't think Australopithecus would ever have seen a megalodon off the shores of Africa, but it's still fascinating to say.

• 34:34Speaker 01

  Maybe not a Pithecus spider, you never know, come across a dead one on a beach.

• 34:38Tristan Hughes?

  Well, that's the thing, like, do you think there were cases where there would have been dead megalodons that end up being washed up on the beach? Like, sometimes you get with beached whales today.

• 34:47Speaker 01

  Yeah, there's a much closer story, though, about megalodons and humans. I'd love to tell you while we've got time. Megalodons probably saved more human lives than they've ever taken, because back in medieval days in Europe, it was very common for people to poison their enemies. And so Europeans of the day, both the Germans, Italians and French, developed these ornate little trees made of silver, and they used to hang fossil sharks teeth from chains, so that before you toasted your friends or your enemies, you would all dip your wine goblets into a shark's tooth, and then watch it for a minute, and then see if the colour of the silver band around that shark's tooth changed its

• 35:30Speaker 01

  colour. Because apparently, and this has been studied by chemists who have written papers on it, arsenic, which was the common poison of the day, would affect the colour of the silver band around the tooth, and it would stain it, make it go dark. So you knew then someone was trying to poison you. So these beautiful jewellery trees, full of megalodon teeth, are called the Nattesungen or Adder's teeth in German. They also have a French name, the languier. And you can find them in museums around the world in Europe, you know. So it's quite possible that this saved a lot of human lives due to megalodon teeth with little silver plaspes around them. It's quite an interesting side story. There's

• 36:11Speaker 01

  also megalodons have been used in archaeology. The Mayans offered megalodon teeth to their gods, have been found at the temple in Palenque, Mexico, dated between 200 and 600 AD.

• 36:23Speaker 01

  And there's other parts of the world where megalodon teeth have been found in in different burial chambers and so on. Even Pliny the Elder referred to megalodon teeth as the glossopetra, or tongue stones of saints. So back in AD seventy three, they believed they fell from the sky at the eclipse of the moon and were helpful for, guess what? Appeasing flatulence in humans. So megalodons have been serving the needs of humans for hundreds of years.

• 36:50Tristan Hughes?

  Pliny the Elder, that naturalist, a very stern naturalist, even he knew of megalodon. So megalodon teeth have been discovered by humans even back into ancient, ancient times, John?

• 37:02Speaker 01

  Yes, yes, even further back in archaeology, back in the North American Indians around Chesapeake Bay, where we're using some of these fossil sharks' teeth for implements and hand tools and things like that. I've written a big section in my book about megalodons in archaeology and history, so you can get further details about it.

• 37:20Tristan Hughes?

  If people have known about these teeth for so long, do you see big misconceptions about the megalodon emerging over time in how they envisaged these creatures that had these massive teeth? Do you see kind of misconceptions emerging in the popular world all the way down to the present day?

• 37:37Speaker 01

  Yeah, yeah. Oh, absolutely, yeah. Basically, the popular misconceptions of megalodon as a giant white shark has just gone out the window. This recent slew of papers have been published in the last year or so about the body shape and the scales and the morphology of the body and how it probably swam much more slowly than the living white sharks. And also the fact that it's no longer deemed by paleontologists to be on the lineage leading to the living white shark, that it's a completely separate lineage that goes back to the age of dinosaurs, whereas the Mako sharks evolved way back in time as well, just after the age of dinosaurs, and continued their lineage right up, leading to the modern white shark, which is a highly evolved Mako shark with serrated teeth, basically.

• 38:21Speaker 01

  So when we look at it from that perspective of the evolution of the lineages as being separate, not related, we have no cause or reason to restore megalodon like a white shark anymore, like it is in every single movie ever made about it.

• 38:35Tristan Hughes?

  And are there myths still that there might be a megalodon or two out there in the depths of the oceans?

• 38:40Speaker 01

  There are myths, but there's no evidence. I mean, I explore this deeply in the book. I mean, there's been lots of submersibles going down to the deep ocean and deep cameras and things. And look, for a population of megalodons to be alive today, we wouldn't go to the deep ocean. We'd go to the surface because that's where the prey is. They'd be eating whales, large whales. And we would see them and occasionally one would die and be washed up on a beach. But no, we get even the rarest of whales that are known from one or two specimens occasionally get washed up on beaches and that's how we know about them. So I think there's absolutely zero evidence that megalodon's out there. The youngest dated shark's teeth come from about three million years ago. There's no evidence of a megalodon tooth younger than three million years anywhere on the planet.

• 39:25Speaker 01

  So I don't think we have to fear megalodon. We just have to fear the living sharks.

• 39:30Tristan Hughes?

  But the popularity of megalodon will no doubt endure for many, many, many years to come.

• 39:35Speaker 01

  Oh, yes.

• 39:36Tristan Hughes?

  John, this has been fascinating. Before we completely wrap up, are there any particular moments from your research, from your story covering megalodon, very memorable moments that you'd like to mention before we finish? Or parts of megalodon's story that we haven't covered as much as you feel we probably should?

• 39:53Speaker 01

  Okay, so there's one thing about megalodon that probably did have one enemy, one sort of other predator it had to fear. Of course, everything's vulnerable when you're small. So baby megalodons would have been prey for other sharks. And certainly a predatory sperm whale called leviathan, which had, modern sperm whales have only got teeth in the lower jaw because they eat squid. But leviathan had teeth in the upper jaw as well as the lower jaw. So it was a more carnivorous, more predatory sperm whale than any of the sperm whales alive today. And at about the same size or not quite as large as, as the biggest megalodon we're speculating, it was close to the same body size as megalodon, but not quite.

• 40:35Speaker 01

  Maybe reaching, you know, up to about eighteen metres, something like that.

• 40:41Speaker 01

  But it's quite possible that Megalodon was preyed on by Leviathan, especially smaller ones, and vice versa, Megalodon preyed on smaller Leviathans. So, you know, Megalodon didn't just have it easy. It wasn't, you know, good to be the king at the top of the food chain with nothing to worry about. They still had something that would have preyed on them.

• 41:01Tristan Hughes?

  John, this has been such a wonderful conversation, just like our last one as well. Last but certainly not least, you have written a book all about Megalodon and the whole history of sharks, it is called?

• 41:13Speaker 01

  The Secret History of Sharks: The Rise of the Ocean's Most Fearsome Predators. And there's also the audiobook out, which I narrated, actually.

• 41:21Tristan Hughes?

  Absolutely fantastic, John. Well, it just goes to me to say, thank you so much for taking the time to come on the podcast today.

• 41:27Speaker 01

  My pleasure, Tricia.

• 41:31Tristan Hughes?

  Well, there you go. There was Professor John Long bringing to an end this small mini series about prehistoric sharks with this fascinating episode all about the real life Megalodon. I've loved doing these episodes on prehistoric sharks and I hope you guys have too. Please follow the show on Spotify or wherever you get your podcasts. That really helps us and you'll be doing us a massive favour. If you'd also be kind enough to leave us a rating as well, well, we'd really appreciate that. Lastly, don't forget, you can also listen to us and all of History Hit's podcasts ad-free and watch hundreds of TV documentaries when you subscribe at historyhit.com/subscribe.