WEBVTT 00:00:00.000 --> 00:00:02.919 Welcome to the Deep Dive. Our mission here is 00:00:02.919 --> 00:00:05.379 pretty straightforward. We take a massive stack 00:00:05.379 --> 00:00:07.940 of sources, peer -reviewed research, historical 00:00:07.940 --> 00:00:11.839 archives, taphonomic data, and we extract the 00:00:11.839 --> 00:00:13.980 absolute best insights so you are fully informed 00:00:13.980 --> 00:00:16.059 on the topic. Right. We're skipping the textbook 00:00:16.059 --> 00:00:17.859 summaries and getting straight to the good stuff. 00:00:18.160 --> 00:00:21.440 Exactly. And today, we are heading into the early 00:00:21.440 --> 00:00:25.100 Jurassic Oceans to look at a marine reptile whose 00:00:25.100 --> 00:00:28.480 biological reality is honestly just as wild as 00:00:28.480 --> 00:00:31.519 its history. We were talking about the Temnodontosaurus. 00:00:31.699 --> 00:00:33.600 Oh, this is a perfect topic. The source material 00:00:33.600 --> 00:00:36.179 on this genus offers such a great cross -section 00:00:36.179 --> 00:00:39.100 of paleontological history. Tracing the literature 00:00:39.100 --> 00:00:41.759 on Temnodontosaurus is basically tracing how 00:00:41.759 --> 00:00:43.960 comparative anatomy became a real science. Yeah. 00:00:44.159 --> 00:00:46.060 And at the same time, we're reconstructing this. 00:00:46.719 --> 00:00:49.880 terrifying apex predator. So to give you a baseline, 00:00:49.939 --> 00:00:52.079 we're looking at the lower Jurassic, roughly 00:00:52.079 --> 00:00:55.719 200 to 175 million years ago. Right. The land 00:00:55.719 --> 00:00:57.859 is shifting, dinosaurs are doing their thing, 00:00:58.119 --> 00:01:00.240 but the oceans are ruled by entirely different 00:01:00.240 --> 00:01:03.539 lineages. Temnodontosaurus is an extinct genus 00:01:03.539 --> 00:01:06.780 of these large dolphin -like marine reptiles. 00:01:07.079 --> 00:01:09.700 Highly derived neohithiosaurians for being technical. 00:01:09.879 --> 00:01:11.799 Right. But before we get stuck in the taxonomic 00:01:11.799 --> 00:01:13.640 weeds, I want to jump straight into the physical 00:01:13.640 --> 00:01:16.459 extremes of this animal. The visual apparatus 00:01:16.459 --> 00:01:18.959 alone just, it breaks our understanding of deep 00:01:18.959 --> 00:01:21.840 sea biology. What's fascinating here is the sheer 00:01:21.840 --> 00:01:25.019 scale of the cranium morphometrics. We are looking 00:01:25.019 --> 00:01:27.939 at an organism that likely possessed the largest 00:01:27.939 --> 00:01:30.840 eyes in the entire history of the animal kingdom. 00:01:30.939 --> 00:01:33.459 Larger than anything alive today. Exactly. To 00:01:33.459 --> 00:01:35.659 give you some scale, the closest modern equivalent 00:01:35.659 --> 00:01:38.739 is the colossal squid. But the eye sockets of 00:01:38.739 --> 00:01:41.640 Temnodontosaurus platyodon are even bigger. We're 00:01:41.640 --> 00:01:44.959 talking over 25 centimeters across. Over 9 .8 00:01:44.959 --> 00:01:48.280 inches. Right. Just massive. Which is wild, staring 00:01:48.280 --> 00:01:51.120 into the dark zones of the Jurassic Ocean with 00:01:51.120 --> 00:01:53.640 eyes the size of dinner plates. It really tells 00:01:53.640 --> 00:01:56.719 you everything about its ecological niche. Sustaining 00:01:56.719 --> 00:01:59.420 an eye that large requires immense caloric energy. 00:01:59.659 --> 00:02:01.939 It's a massive metabolic investment. Because 00:02:01.939 --> 00:02:04.780 it's processing so much visual data in near total 00:02:04.780 --> 00:02:08.659 darkness. Precisely. It's relying almost entirely 00:02:08.659 --> 00:02:11.960 on visual acuity to track movement where other 00:02:11.960 --> 00:02:14.360 senses get scrambled by water pressure or noise. 00:02:14.840 --> 00:02:16.919 That perfectly sets up our roadmap for this deep 00:02:16.919 --> 00:02:19.439 dive. We're going to start with the 19th century 00:02:19.439 --> 00:02:22.240 discovery by Marion Joseph Anning along the Dorset 00:02:22.240 --> 00:02:25.460 Coast. The socioeconomics of that era are fascinating. 00:02:25.699 --> 00:02:28.520 Oh, totally. We'll get into how Victorian scientists 00:02:28.520 --> 00:02:31.620 hilariously misidentified this thing, mistaking 00:02:31.620 --> 00:02:34.960 it for a crocodile, a fish. Even a platypus. 00:02:35.120 --> 00:02:37.520 The platypus phase is incredible. It really is. 00:02:37.740 --> 00:02:39.860 Then we'll strip away those Victorian paleoart 00:02:39.860 --> 00:02:42.539 mistakes, the crystal palace dinosaurs, and look 00:02:42.539 --> 00:02:45.199 at the real biomechanics. Specifically, some 00:02:45.199 --> 00:02:48.360 mind -blowing 2025 research on its stealth technology. 00:02:48.639 --> 00:02:50.860 That new acoustic data changes everything. Yeah. 00:02:51.020 --> 00:02:52.840 And finally, we'll look at the battle scars, 00:02:53.120 --> 00:02:55.479 the diet, and how it ended up becoming what scientists 00:02:55.479 --> 00:02:59.020 call a taxonomic wastebasket. Okay, let's unpack 00:02:59.020 --> 00:03:02.729 this discovery. The 1810s. Right. The historical 00:03:02.729 --> 00:03:04.729 context is so important because the scientists 00:03:04.729 --> 00:03:07.550 of the 1810s were incredibly constrained. The 00:03:07.550 --> 00:03:10.270 whole concept of extinction, which Georges Cuvier 00:03:10.270 --> 00:03:12.930 had just proposed, was still highly controversial. 00:03:13.310 --> 00:03:15.689 People couldn't fathom that a species could just 00:03:15.689 --> 00:03:18.969 vanish. So let's head to the cliffs of Black 00:03:18.969 --> 00:03:22.590 Ven in Dorset, England. Along the Blue Lias Formation. 00:03:22.909 --> 00:03:25.469 Exactly. It's this stretch of coastline made 00:03:25.469 --> 00:03:28.509 of alternating limestone and shale. The erosion 00:03:28.509 --> 00:03:31.090 there is constant, which means fossils are always 00:03:31.090 --> 00:03:33.349 washing out. And this is where Joseph Anning 00:03:33.349 --> 00:03:36.530 finds the first really significant skull. And 00:03:36.530 --> 00:03:40.069 then a few months later, in 1812, his sister, 00:03:40.550 --> 00:03:43.090 the legendary Mary Anning, uncovers the rest 00:03:43.090 --> 00:03:45.729 of the skeleton. The articulated postcranial 00:03:45.729 --> 00:03:48.310 remains, which is just an incredible moment in 00:03:48.310 --> 00:03:50.530 science. But we have to remember the commercial 00:03:50.530 --> 00:03:53.509 reality here. The Annings weren't funded by some 00:03:53.509 --> 00:03:55.669 royal society. No, they were a working class 00:03:55.669 --> 00:03:58.490 family. Finding and selling fossils was literally 00:03:58.490 --> 00:04:00.569 how they put food on the table. Right. And the 00:04:00.569 --> 00:04:02.449 transaction records from our sources are pretty 00:04:02.449 --> 00:04:05.169 revealing. That first massive skeleton was bought 00:04:05.169 --> 00:04:08.110 by a local lord for 23 pounds. Which was decent 00:04:08.110 --> 00:04:10.750 money for the innings at the time, but a complete 00:04:10.750 --> 00:04:13.479 steal for a paradigm shifting fossil. a total 00:04:13.479 --> 00:04:16.139 bargain. Because from there, the Lord sells it 00:04:16.139 --> 00:04:18.160 to William Bullock's private museum in London. 00:04:18.819 --> 00:04:21.279 And eventually, the British Museum, now the Natural 00:04:21.279 --> 00:04:25.139 History Museum, buys it for roughly £47. And 00:04:25.139 --> 00:04:27.779 the skull is still there today, cataloged as 00:04:27.779 --> 00:04:31.360 NHMUK PVR, living in 58. But the tragedy is that 00:04:31.360 --> 00:04:34.980 the rest of the skeleton Mary found. Lost. Completely 00:04:34.980 --> 00:04:37.639 lost to science during those institutional transitions. 00:04:37.980 --> 00:04:40.779 So early scientists only had this massive skull 00:04:40.779 --> 00:04:43.620 to go on. And this leads to Sir Everard Home. 00:04:43.819 --> 00:04:47.720 Between 1814 and 1819, he publishes six papers 00:04:47.720 --> 00:04:50.720 trying to categorize it, and it is a master class 00:04:50.720 --> 00:04:53.279 in scientific panic. He was completely baffled. 00:04:53.300 --> 00:04:55.860 He was trying to map this alien morphology onto 00:04:55.860 --> 00:04:58.060 animals he actually knew. Right. First, he looks 00:04:58.060 --> 00:05:00.300 at the long snout and the cone -shaped teeth, 00:05:00.399 --> 00:05:02.720 and he says it's a crocodile. Which makes superficial 00:05:02.720 --> 00:05:04.699 sense until you look at the eye sockets and the 00:05:04.699 --> 00:05:06.699 skull openings. It clearly wasn't an archosaur. 00:05:06.879 --> 00:05:09.300 So he quickly drops the crocodile idea. Then 00:05:09.300 --> 00:05:12.240 he looks at the backbone, the biconcave vertebrae. 00:05:12.540 --> 00:05:14.879 Amphicillus vertebrae. Right. They dip inward 00:05:14.879 --> 00:05:16.639 on both sides. Why does it make him think it's 00:05:16.639 --> 00:05:19.360 a fish? Because that specific spinal flexibility 00:05:19.360 --> 00:05:22.300 is something you mostly see in fish and primitive 00:05:22.300 --> 00:05:24.959 amphibians. It allows for that side -to -side 00:05:24.959 --> 00:05:28.519 swimming motion. Terrestrial reptiles have vertebrae 00:05:28.519 --> 00:05:30.959 that lock together more rigidly to support their 00:05:30.959 --> 00:05:33.379 weight on land. So home sees fish -like spine 00:05:33.379 --> 00:05:35.639 mechanics, but it's clearly a reptile. And having 00:05:35.639 --> 00:05:38.579 no concept of a fully marine reptile, he panics 00:05:38.579 --> 00:05:41.040 and leans into the fish angle. But it gets weirder. 00:05:41.040 --> 00:05:43.019 He then tries to connect it to the platypus. 00:05:43.160 --> 00:05:45.459 The ernithorrhynchus vase, yes. I mean, how do 00:05:45.459 --> 00:05:48.459 you jump from giant sea dragon to a platypus? 00:05:48.600 --> 00:05:51.199 Well, you have to realize Europe had only recently 00:05:51.199 --> 00:05:53.360 discovered the platypus and it completely broke 00:05:53.360 --> 00:05:56.350 their classification system. It had fur, laid 00:05:56.350 --> 00:05:59.769 eggs, had venomous spurs. So Holm basically takes 00:05:59.769 --> 00:06:02.790 the two most confusing animals he knows and decides 00:06:02.790 --> 00:06:04.769 they must be related. Because they both break 00:06:04.769 --> 00:06:07.910 the rules. That is amazing logic. Finally, in 00:06:07.910 --> 00:06:11.069 1819, he compromises and calls it a halfway point 00:06:11.069 --> 00:06:13.550 between a thalamander and a lizard. He names 00:06:13.550 --> 00:06:17.209 it Proteasaurus. It wasn't his best work. but 00:06:17.209 --> 00:06:20.170 it shows how hard it was to fit an extinct lineage 00:06:20.170 --> 00:06:23.110 into these neat, pre -existing boxes. So when 00:06:23.110 --> 00:06:25.290 does it actually get its modern name? Well, the 00:06:25.290 --> 00:06:27.410 name Ichthyosaurus gets officially published 00:06:27.410 --> 00:06:32.050 in 1821 by Delabèche and Coneybear. They look 00:06:32.050 --> 00:06:34.850 at the black ven skull and call it Ichthyosaurus 00:06:34.850 --> 00:06:38.149 platyodon. Platyodon meaning flat teeth. Right. 00:06:38.410 --> 00:06:40.230 And it stayed classified as an ichthyosaurus 00:06:40.230 --> 00:06:44.189 for decades until 1889, when Richard Lidecker 00:06:44.189 --> 00:06:46.649 realized the teeth were entirely different from 00:06:46.649 --> 00:06:48.910 every other ichthyosaur. Right. The teeth were 00:06:48.910 --> 00:06:51.509 cutting tools, not just grabbing pins. Exactly. 00:06:51.689 --> 00:06:54.949 So Lidecker creates the new genus, Temnodontosaurus, 00:06:55.689 --> 00:06:57.670 the cutting -toothed lizard. Which really marks 00:06:57.670 --> 00:07:00.750 a shift. Paleontology was finally moving away 00:07:00.750 --> 00:07:02.670 from lumping everything together and starting 00:07:02.670 --> 00:07:05.050 to look at specific traits like dental architecture 00:07:05.050 --> 00:07:07.470 to separate these animals. It was a maturation 00:07:07.470 --> 00:07:09.269 of the field, definitely. And while all this 00:07:09.269 --> 00:07:11.110 academic debate is happening, the public is going 00:07:11.110 --> 00:07:13.329 crazy for these monsters, which brings us to 00:07:13.329 --> 00:07:16.910 1854 and the Crystal Palace dinosaurs in London. 00:07:17.209 --> 00:07:20.089 Birth of public paleoart. Imagine being a Victorian 00:07:20.089 --> 00:07:22.329 walking through this park and seeing these life 00:07:22.329 --> 00:07:25.689 size concrete sea monsters. Benjamin Waterhouse 00:07:25.689 --> 00:07:27.509 Hawkins. built them. And considering it was the 00:07:27.509 --> 00:07:29.949 1850s, he actually got a few things right. He 00:07:29.949 --> 00:07:32.689 did. He looked at modern whales and dolphins 00:07:32.689 --> 00:07:36.110 and realized that a fast marine predator needs 00:07:36.110 --> 00:07:39.089 smooth skin. So he didn't cover them in crocodile 00:07:39.089 --> 00:07:41.990 scales. He also gave them dorsal fins and tail 00:07:41.990 --> 00:07:44.110 fins, even though he didn't have much bone evidence 00:07:44.110 --> 00:07:46.810 for it. He understood hydrodynamic stabilization. 00:07:47.850 --> 00:07:51.230 But the things he got wrong. Oh, they are spectacular 00:07:51.230 --> 00:07:53.569 mistakes. Let's talk about the eyes. They look 00:07:53.569 --> 00:07:56.500 like mechanical armored portholes. Right, the 00:07:56.500 --> 00:07:58.720 sclerotic rings. We know teminodontosaurs had 00:07:58.720 --> 00:08:02.500 massive eyes and within those eyes are bony rings. 00:08:02.680 --> 00:08:05.560 They handle water pressure, right? Exactly. Sclerotic 00:08:05.560 --> 00:08:08.139 rings maintain the shape of the eyeball against 00:08:08.139 --> 00:08:11.620 intense hydrostatic pressure. but their internal 00:08:11.620 --> 00:08:14.740 structures. Hawkins saw these bony rings preserved 00:08:14.740 --> 00:08:17.899 in the fossil skulls and assumed they were external 00:08:17.899 --> 00:08:20.759 armor. Like actual bone goggles sitting on the 00:08:20.759 --> 00:08:22.959 outside of the face. Precisely. Ignoring eyelids 00:08:22.959 --> 00:08:25.240 entirely. It looks so weird. And then there's 00:08:25.240 --> 00:08:27.560 the posture. He sculpted them crawling up in 00:08:27.560 --> 00:08:29.379 the rocks like seals. That was Richard Owen's 00:08:29.379 --> 00:08:31.439 fault. Owen was the top comparative anatomist 00:08:31.439 --> 00:08:33.720 at the time and he completely misread the flipper 00:08:33.720 --> 00:08:36.100 bones. Because of the hyper phalange, the extra 00:08:36.100 --> 00:08:39.490 finger bones. Yes. The flippers have dozens of 00:08:39.490 --> 00:08:42.289 extra finger bones, making a stiff paddle. Owen 00:08:42.289 --> 00:08:44.389 thought these bones were actually internal versions 00:08:44.389 --> 00:08:47.169 of external scales, so he concluded the limb 00:08:47.169 --> 00:08:49.610 couldn't swim effectively. Which implies they 00:08:49.610 --> 00:08:51.870 must have needed to come ashore to rest or breed, 00:08:52.049 --> 00:08:54.549 like modern sea turtles. Right, which completely 00:08:54.549 --> 00:08:57.950 ignores the reality of their rib cages. A Temnodontosaurus 00:08:57.950 --> 00:09:00.629 was so massive that if it hauled itself onto 00:09:00.629 --> 00:09:03.389 a beach, its own body weight would crush its 00:09:03.389 --> 00:09:06.190 lungs. It would suffocate. Asphyxiation on the 00:09:06.190 --> 00:09:09.210 beach, not very apex predator. Plus, we know 00:09:09.210 --> 00:09:11.929 now they gave birth to live young in the water. 00:09:12.230 --> 00:09:15.629 Viviparity, yes. No beaches required. The tail 00:09:15.629 --> 00:09:17.669 was another issue at Crystal Palace. He made 00:09:17.669 --> 00:09:20.110 it look like a giant eel tail, slithering over 00:09:20.110 --> 00:09:23.070 the rocks. Anguilliform locomotion was the prevailing 00:09:23.070 --> 00:09:26.289 theory then, but we now know it used funniform 00:09:26.289 --> 00:09:29.519 locomotion. Tuna -like swimming. Exactly. The 00:09:29.519 --> 00:09:31.600 vertebrae near the back of the animal are very 00:09:31.600 --> 00:09:33.659 robust. It wasn't wiggling its whole body like 00:09:33.659 --> 00:09:37.039 a snake. It was holding its body stiff and using 00:09:37.039 --> 00:09:39.820 rapid high -frequency beats of just the tail 00:09:39.820 --> 00:09:42.720 fin. The spine literally bends downward at a 00:09:42.720 --> 00:09:45.399 35 -degree angle to support the lower lobe of 00:09:45.399 --> 00:09:47.419 that tail fin, right? Yes, the semilunar tail 00:09:47.419 --> 00:09:49.820 fin. Highly efficient for cruising and bursts 00:09:49.820 --> 00:09:52.820 of speed. Okay, so let's transition from the 00:09:52.820 --> 00:09:56.320 Victorian concrete monsters to the biological 00:09:56.320 --> 00:09:59.299 reality because we need to talk about the sheer 00:09:59.299 --> 00:10:02.019 scale of this animal. Temnodontosaurus is easily 00:10:02.019 --> 00:10:04.399 one of the largest members of its specific clade, 00:10:04.759 --> 00:10:07.139 the Parvipelvians. The estimates in the literature 00:10:07.139 --> 00:10:09.659 average around nine meters long or about 30 feet, 00:10:09.879 --> 00:10:12.799 which is massive. A mature T -trigadodon skull 00:10:12.799 --> 00:10:16.600 alone is nearly 1 .8 meters, over five and a 00:10:16.600 --> 00:10:19.169 half feet of just head. And the Rutland Sea Dragon 00:10:19.169 --> 00:10:22.169 discovery in 2021 pushed that even further. They 00:10:22.169 --> 00:10:24.950 found a nearly complete skeleton in a UK reservoir 00:10:24.950 --> 00:10:27.629 that measures slightly past 10 meters. Thirty 00:10:27.629 --> 00:10:30.029 three feet. And having an articulated skeleton 00:10:30.029 --> 00:10:31.970 like the Rutland specimen is crucial because 00:10:31.970 --> 00:10:34.370 it stops us from making math errors. You're talking 00:10:34.370 --> 00:10:37.210 about the Bans Abbey myth, the 16 meter mega 00:10:37.210 --> 00:10:39.590 monster. Exactly. For decades, there was this 00:10:39.590 --> 00:10:43.029 rumor of a 16 meter temdontosaurus based on some 00:10:43.029 --> 00:10:45.809 isolated vertebrae found in Germany in 1922. 00:10:46.090 --> 00:10:48.549 How did they get the math so wrong? Christopher 00:10:48.549 --> 00:10:51.289 McGowan tried to scale up from a complete smaller 00:10:51.289 --> 00:10:54.509 skeleton. He found the ratio between the vertebrae 00:10:54.509 --> 00:10:57.210 and the total body length, but the initial body 00:10:57.210 --> 00:10:59.370 length he used for his baseline was wrong. So 00:10:59.370 --> 00:11:02.110 he multiplied a mistake. Giggly. He applied a 00:11:02.110 --> 00:11:05.669 flawed ratio to these massive 22 centimeter vertebrae 00:11:05.669 --> 00:11:08.529 from Bans Abbey, and the result was artificially 00:11:08.529 --> 00:11:12.659 inflated. Modern consensus caps them around 10, 00:11:12.740 --> 00:11:15.419 maybe 11 meters tops. Which is still a terrifying 00:11:15.419 --> 00:11:18.019 size for an ocean predator. And here's where 00:11:18.019 --> 00:11:19.779 it gets really interesting. Let's talk about 00:11:19.779 --> 00:11:21.360 the flippers, because they aren't just paddles, 00:11:21.480 --> 00:11:24.399 they are stealth tech. The 2025 Lindgren paper 00:11:24.399 --> 00:11:27.159 in Nature completely rewrote our understanding 00:11:27.159 --> 00:11:30.259 of this. They looked at a forfin from the Posidonia 00:11:30.259 --> 00:11:33.590 shale in Germany. And this shale is famous for 00:11:33.590 --> 00:11:36.129 perfect soft tissue preservation because the 00:11:36.129 --> 00:11:38.909 ocean floor had zero oxygen. Anoxic conditions. 00:11:39.370 --> 00:11:42.110 No bacteria to rot the soft tissue away. Right. 00:11:42.350 --> 00:11:44.509 And what they found on the trailing edge of this 00:11:44.509 --> 00:11:46.889 one meter flipper was soft tissue structures 00:11:46.889 --> 00:11:49.250 they called chondroderms. It essentially means 00:11:49.250 --> 00:11:51.149 the trailing edge of the flipper wasn't smooth. 00:11:51.330 --> 00:11:53.820 It was serrated. Like a steak knife. Exactly. 00:11:54.240 --> 00:11:57.240 And in fluid dynamics, if a massive, smooth paddle 00:11:57.240 --> 00:12:01.000 moves through water, it creates huge, turbulent 00:12:01.000 --> 00:12:04.179 vortices. And those vortices create low -frequency 00:12:04.179 --> 00:12:06.759 sound waves. Which alerts every fish in the area 00:12:06.759 --> 00:12:09.299 that a bus -sized predator is coming. Precisely. 00:12:09.639 --> 00:12:11.820 Marine animals have lateral line systems tuned 00:12:11.820 --> 00:12:14.139 perfectly to detect those pressure waves. So 00:12:14.139 --> 00:12:17.259 the serrated edge acts as noise -cancelling technology. 00:12:17.399 --> 00:12:20.139 It breaks up the large vortices into tiny micro 00:12:20.139 --> 00:12:23.080 -vortices that dissipate instantly. It is the 00:12:23.080 --> 00:12:25.700 exact same aerodynamic principle as an owl's 00:12:25.700 --> 00:12:28.139 wing. Silent flight, but underwater. So you have 00:12:28.139 --> 00:12:30.740 a 30 -foot submarine swinging these massive flippers 00:12:30.740 --> 00:12:34.240 and it makes zero sound. None. And the histological 00:12:34.240 --> 00:12:36.700 analysis from that same study showed massive 00:12:36.700 --> 00:12:39.500 amounts of eumelanin. Dark pigmentation. Dark, 00:12:39.700 --> 00:12:42.399 likely counter -shaded or striped. So it's acoustically 00:12:42.399 --> 00:12:45.330 silent. visually cloaked in the dark water and 00:12:45.330 --> 00:12:47.269 tracking you with eyes the size of dinner plates. 00:12:47.350 --> 00:12:49.549 That is pure nightmare fuel. And then there's 00:12:49.549 --> 00:12:51.389 the bite itself. The jaws are so specialized 00:12:51.389 --> 00:12:53.830 the literature calls it olakodon teeth. Yes. 00:12:54.669 --> 00:12:56.889 Olakodon jaw structure means the teeth aren't 00:12:56.889 --> 00:12:59.350 sitting in individual sockets like our teeth 00:12:59.350 --> 00:13:02.649 do. The jaw bone has a continuous uninterrupted 00:13:02.649 --> 00:13:05.190 trench and the teeth erupt straight out of that 00:13:05.190 --> 00:13:07.429 groove. And the teeth themselves are built for 00:13:07.429 --> 00:13:10.409 violence. They have carrony. Enamel ridges running 00:13:10.409 --> 00:13:13.850 up the tooth. Temnodontosaurus platyodon specifically 00:13:13.850 --> 00:13:16.549 has two of these ridges by carinate morphology. 00:13:16.750 --> 00:13:19.169 What does that actually do for the tooth mechanically? 00:13:19.409 --> 00:13:21.950 It acts like architectural reinforcement. When 00:13:21.950 --> 00:13:25.169 the jaw slams shut on something hard, those ridges 00:13:25.169 --> 00:13:27.490 channel the physical stress away from the tip 00:13:27.490 --> 00:13:29.889 of the tooth. It prevents the enamel from shattering. 00:13:29.990 --> 00:13:32.090 Which tells us they weren't just eating soft 00:13:32.090 --> 00:13:34.889 squid, they were biting through armor and bone. 00:13:35.149 --> 00:13:37.169 It's an over -engineered jaw. They were eating 00:13:37.169 --> 00:13:38.850 anything they wanted. And we have the smoking 00:13:38.850 --> 00:13:42.809 gun for that. Specimen SMNS -50000. It's a gorgeous 00:13:42.809 --> 00:13:45.289 fossil where the stomach contents are perfectly 00:13:45.289 --> 00:13:47.690 preserved. The gastric mass in that specimen 00:13:47.690 --> 00:13:50.070 is a goldmine. Inside its stomach they found 00:13:50.070 --> 00:13:53.029 the chopped up remains of three baby stenopterygias. 00:13:53.289 --> 00:13:55.769 Which is a smaller, completely different genus 00:13:55.769 --> 00:13:58.330 of ichthyosaur. So we have definitive proof of 00:13:58.330 --> 00:14:00.529 them hunting other marine reptiles. At the wild 00:14:00.529 --> 00:14:02.590 part is what else was in the stomach. A huge 00:14:02.590 --> 00:14:05.990 tangled ball of cephalopod hooks. Thousands of 00:14:05.990 --> 00:14:08.789 them. Early Jurassic squid had these heavy chitinous 00:14:08.789 --> 00:14:11.009 hooks on their tentacles. So the Timodontosaurus 00:14:11.009 --> 00:14:13.750 eats the squid, the stomach acid melts the meat, 00:14:13.889 --> 00:14:16.720 but the hooks just sit there. Chitin is incredibly 00:14:16.720 --> 00:14:19.820 hard to digest for vertebrates. So over time, 00:14:20.100 --> 00:14:23.500 these hooks clump together into this dense, thorny 00:14:23.500 --> 00:14:27.039 mass, a massive internal bezor. Does it help 00:14:27.039 --> 00:14:29.779 with digestion, like how birds swallow rocks? 00:14:29.980 --> 00:14:31.899 Or is it just a massive problem for the animal? 00:14:31.919 --> 00:14:33.580 It's a huge problem. It takes a valuable stomach 00:14:33.580 --> 00:14:36.220 capacity. The consensus is that they had to periodically 00:14:36.220 --> 00:14:38.419 vomit these masses up to clear their stomachs. 00:14:38.419 --> 00:14:40.580 It's coughing up a giant hairball of sharp squid 00:14:40.580 --> 00:14:43.539 hooks. And we have fossilized vomit bromelites 00:14:43.539 --> 00:14:46.350 to prove it. full of hooks and crushed bone. 00:14:46.610 --> 00:14:50.090 Gross, but fascinating. But hunting huge prey 00:14:50.090 --> 00:14:53.029 comes with risks. Let's talk about paleopathology, 00:14:53.429 --> 00:14:56.110 the battle scars. This is where we see just how 00:14:56.110 --> 00:14:59.809 brutal their ecosystem was. Specimen SMNS 15950 00:14:59.809 --> 00:15:02.850 is a perfect example. The skull has 10 circular 00:15:02.850 --> 00:15:05.230 puncture wounds right across the face. And the 00:15:05.230 --> 00:15:07.809 bone shows extensive remodeling around the wounds, 00:15:08.470 --> 00:15:11.110 meaning the animal survived the bite and it healed 00:15:11.110 --> 00:15:13.509 over time. But the spacing of the teeth marks 00:15:13.509 --> 00:15:15.789 just a few centimeters apart, and a straight 00:15:15.789 --> 00:15:18.490 line points to a very specific attacker, right? 00:15:18.929 --> 00:15:22.110 Yes. Taphonomic analysis suggests two main suspects. 00:15:22.750 --> 00:15:25.250 It was either another Temnibonosaurus in a territorial 00:15:25.250 --> 00:15:28.269 or mating dispute. A face -biting contest. Exactly. 00:15:28.549 --> 00:15:31.549 Or it was an attack from a massive marine crocodile, 00:15:32.009 --> 00:15:35.429 a phallotosuchian like Steniosaurus. A 30 -foot 00:15:35.429 --> 00:15:38.629 stealth ichthyosaur, brawling with a fully marine 00:15:38.629 --> 00:15:41.409 crocodile. The Jurassic Ocean was not a safe 00:15:41.409 --> 00:15:44.210 place. Not at all. And those bites reveal a major 00:15:44.210 --> 00:15:46.909 structural weakness in the Temnodontosaurus skull. 00:15:47.090 --> 00:15:49.470 The thin jaws. I read that a lot of specimens 00:15:49.470 --> 00:15:52.470 like the Tina retingensis holotype have these 00:15:52.470 --> 00:15:54.549 deep gouges on the lower jaw. Because the bone 00:15:54.549 --> 00:15:57.330 there was virtually unprotected. Unlike modern 00:15:57.330 --> 00:15:59.629 whales that have thick blubber or huge muscles 00:15:59.629 --> 00:16:02.409 over their jaws, the bone of a Temnodontosaurus 00:16:02.409 --> 00:16:04.549 mandible was basically right under the skin. 00:16:05.200 --> 00:16:07.879 subcutaneous bone, so any glancing bite would 00:16:07.879 --> 00:16:10.100 scrape right against the periosteum. It's an 00:16:10.100 --> 00:16:13.120 evolutionary trade -off. To swing that long snout 00:16:13.120 --> 00:16:15.159 quickly through the water to catch fish, it had 00:16:15.159 --> 00:16:18.620 to be streamlined. No bulky armor. But that made 00:16:18.620 --> 00:16:21.320 it incredibly fragile in a fight. So where were 00:16:21.320 --> 00:16:23.500 these massive battles happening? For a long time, 00:16:23.519 --> 00:16:25.600 we thought this was just a European animal found 00:16:25.600 --> 00:16:28.899 in the UK, Germany, France. Mostly confined to 00:16:28.899 --> 00:16:31.039 the shallow seas of the Tethys Ocean, according 00:16:31.039 --> 00:16:33.220 to older models. But then we look at a discovery 00:16:33.220 --> 00:16:36.559 from the Atacama Desert in Chile. Yes. Specimen 00:16:36.559 --> 00:16:41.940 sgo .pv .324. A jaw fragment found in 1988 in 00:16:41.940 --> 00:16:44.179 volcanic rock from the La Negra Formation. It 00:16:44.179 --> 00:16:47.700 sat in a museum until 2020. And the ammonite 00:16:47.700 --> 00:16:50.519 fossils found near it. definitively dated to 00:16:50.519 --> 00:16:52.740 the early Jurassic. Which means this animal was 00:16:52.740 --> 00:16:54.740 swimming off the coast of South America. In the 00:16:54.740 --> 00:16:57.860 Panthalassa Super Ocean. This completely validates 00:16:57.860 --> 00:17:00.299 the Hispanic Corridor Hypothesis. Which is the 00:17:00.299 --> 00:17:02.720 idea that there was a deep water channel connecting 00:17:02.720 --> 00:17:05.519 the Tethys Sea in Europe to the global Panthalassa 00:17:05.519 --> 00:17:07.779 Ocean long before the continents fully broke 00:17:07.779 --> 00:17:10.599 apart. Exactly. If we connect this to the bigger 00:17:10.599 --> 00:17:13.940 picture, finding a Temnodontosaurus in Chile 00:17:13.940 --> 00:17:16.640 proves it wasn't just a local apex predator, 00:17:17.059 --> 00:17:20.180 it was a globally distributed pelagic titan riding 00:17:20.180 --> 00:17:22.880 global ocean currents. It had the stamina and 00:17:22.880 --> 00:17:25.460 osmoregulatory system to cross the entire planet. 00:17:25.710 --> 00:17:28.549 Which is amazing, but it also creates a massive 00:17:28.549 --> 00:17:30.289 headache for the scientists trying to classify 00:17:30.289 --> 00:17:33.069 it today. The taxonomy is... well, it's a mess. 00:17:33.369 --> 00:17:35.609 A wastebasket taxon, that's the phrase used in 00:17:35.609 --> 00:17:37.630 the sources. Let's look at the species' roster. 00:17:37.829 --> 00:17:40.349 We've got the main ones. Platyodon, Trigonodon, 00:17:40.529 --> 00:17:42.650 Crassimonus, Cetlandicus, and the scarred -up 00:17:42.650 --> 00:17:45.650 Neurotengensis. Those form the relatively stable 00:17:45.650 --> 00:17:48.269 core, but then you have all these oddball fossils 00:17:48.269 --> 00:17:50.269 that got thrown into the genus over the last 00:17:50.269 --> 00:17:53.069 hundred years. Like Kyricephalus. It has this 00:17:53.069 --> 00:17:56.339 super broad head and weird... bulbous tooth roots 00:17:56.339 --> 00:17:58.579 that don't match the bicarinate teeth we talked 00:17:58.579 --> 00:18:00.640 about. Right. And then you have the issue of 00:18:00.640 --> 00:18:03.180 ontogeny, how the animal changes as it grows 00:18:03.180 --> 00:18:05.660 from a baby to an adult. The T. riser mistake. 00:18:06.019 --> 00:18:09.480 Ah, yes. In 1974, researchers found three skulls 00:18:09.480 --> 00:18:12.519 with massive eyes and really short snouts. They 00:18:12.519 --> 00:18:15.480 declared a new species, Temodontosaurus riser. 00:18:15.680 --> 00:18:18.539 But then in 1995, Christopher McGowan looks closer 00:18:18.539 --> 00:18:21.259 and goes, wait a minute. He realized they weren't 00:18:21.259 --> 00:18:23.960 a new species. They were just baby platyodon 00:18:23.960 --> 00:18:27.430 specimens. Reptile skulls change their proportions 00:18:27.430 --> 00:18:30.630 drastically as they grow. The babies have huge 00:18:30.630 --> 00:18:33.650 eyes and short faces. Classic neotenic features. 00:18:33.829 --> 00:18:35.450 Exactly. If you don't have a complete growth 00:18:35.450 --> 00:18:37.809 series, a juvenile looks like a totally different 00:18:37.809 --> 00:18:40.119 animal. But the biggest problem threatening the 00:18:40.119 --> 00:18:43.640 whole temnodontosaurus name is convergent evolution. 00:18:44.099 --> 00:18:46.019 Because water forces everything to look the same. 00:18:46.160 --> 00:18:49.819 Right. Water is 800 times denser than air. If 00:18:49.819 --> 00:18:52.200 you want to swim fast and eat things, physics 00:18:52.200 --> 00:18:55.440 demands a very specific shape. A fusiform, torpedo 00:18:55.440 --> 00:18:58.279 -shaped body, and a long -toothed snout. So if 00:18:58.279 --> 00:19:00.940 a scientist digs up a giant, long -snouted skull 00:19:00.940 --> 00:19:04.299 in Jurassic Rock, They assume it's a Temnodontosaurus, 00:19:04.759 --> 00:19:07.299 but it might just be a completely unrelated animal 00:19:07.299 --> 00:19:09.299 that evolved the same shape to solve the same 00:19:09.299 --> 00:19:11.980 physics problem. And that's exactly what a 2022 00:19:11.980 --> 00:19:14.380 computational study by Lavery and colleagues 00:19:14.380 --> 00:19:17.839 found. They ran a massive data matrix of skeletal 00:19:17.839 --> 00:19:20.099 traits. And the computer basically spat out that 00:19:20.099 --> 00:19:23.799 Temnodontosaurus is polyphaletic. Yes. A polyphaletic 00:19:23.799 --> 00:19:26.440 group is essentially an artificial human category. 00:19:26.680 --> 00:19:29.440 It means the animals linked in this group do 00:19:29.440 --> 00:19:32.460 not share an exclusive direct common ancestor. 00:19:32.599 --> 00:19:35.259 So the coarse species might be related, but a 00:19:35.259 --> 00:19:37.599 bunch of the others are evolutionary imposters. 00:19:37.920 --> 00:19:40.779 They're different lineages wearing the same hydrodynamic 00:19:40.779 --> 00:19:42.799 disguise. So what does this all mean for you, 00:19:42.960 --> 00:19:45.579 the listener? It's a perfect reminder that nature 00:19:45.579 --> 00:19:49.410 is messy. Our Linnean system of neat little Latin 00:19:49.410 --> 00:19:51.990 names often fails to capture the chaotic reality 00:19:51.990 --> 00:19:54.410 of millions of years of evolution. Untangling 00:19:54.410 --> 00:19:57.690 it requires CT scans, fluid dynamics, and admitting 00:19:57.690 --> 00:19:59.769 that century -old labels might just be wrong. 00:20:00.109 --> 00:20:02.190 So, to summarize the journey we've been on today. 00:20:02.400 --> 00:20:05.019 We started on the eroding cliffs with Mary Anning 00:20:05.019 --> 00:20:07.819 uncovering an animal that broke Victorian science. 00:20:08.039 --> 00:20:10.900 We walked past the bizarre armored concrete models 00:20:10.900 --> 00:20:13.539 at Crystal Palace. We dove into the biological 00:20:13.539 --> 00:20:16.700 reality of a 10 meter stealth bomber with noise 00:20:16.700 --> 00:20:19.619 canceling flippers, dark camouflage and jaws 00:20:19.619 --> 00:20:22.339 built to shatter bone. Dominating a global ocean 00:20:22.339 --> 00:20:25.079 from Europe to Chile, brawling with marine crocodiles 00:20:25.079 --> 00:20:27.980 and vomiting up squid hooks. And finally, wrestling 00:20:27.980 --> 00:20:30.380 with the fact that the name Tendodontosaurus 00:20:30.380 --> 00:20:32.880 might just be a convenient label for several 00:20:32.880 --> 00:20:35.640 different apex predators converging on the perfect 00:20:35.640 --> 00:20:37.740 killing design. It's an incredible amount of 00:20:37.740 --> 00:20:40.539 data to synthesize. But before we sign off, there 00:20:40.539 --> 00:20:43.160 is one last provocative thought from the sources 00:20:43.160 --> 00:20:45.460 that we really need to sit with. And it goes 00:20:45.460 --> 00:20:48.940 back to those massive 25 centimeter eyes. Right. 00:20:49.339 --> 00:20:51.799 the key to their predatory success. The eyes 00:20:51.799 --> 00:20:54.059 gave them incredible vision in the dark. But 00:20:54.059 --> 00:20:56.400 because of the way those massive lenses were 00:20:56.400 --> 00:20:58.559 seated on the side of the skull, they created 00:20:58.559 --> 00:21:02.180 a massive physical compromise. A defined absolute 00:21:02.180 --> 00:21:05.019 blind spot directly above the head. Meaning this 00:21:05.019 --> 00:21:07.980 animal had zero visual coverage of the water 00:21:07.980 --> 00:21:10.519 column immediately dorsal to it. If you think 00:21:10.519 --> 00:21:13.220 about the implications of that... It's chilling. 00:21:13.799 --> 00:21:15.559 Evolution usually punishes a blind spot like 00:21:15.559 --> 00:21:18.220 that. Unless. Right. Was it just a harmless trade 00:21:18.220 --> 00:21:20.039 -off because it spent all its time looking down 00:21:20.039 --> 00:21:22.940 into the abyss for prey? Or does a built -in 00:21:22.940 --> 00:21:25.019 blind spot from above mean the Jurassic Oceans 00:21:25.019 --> 00:21:27.279 were even more terrifying than we realize? If 00:21:27.279 --> 00:21:30.140 the ultimate stealth predator can't see what's 00:21:30.140 --> 00:21:32.339 directly above it in the sunlit zone, it makes 00:21:32.339 --> 00:21:35.039 you wonder if there were even larger undiscovered 00:21:35.039 --> 00:21:37.619 surface predators perfectly evolved to attack 00:21:37.619 --> 00:21:39.960 the sea dragon where it couldn't see them coming. 00:21:40.349 --> 00:21:43.910 It perfectly illustrates how answering one biomechanical 00:21:43.910 --> 00:21:47.329 question just opens the door to a much scarier 00:21:47.329 --> 00:21:49.829 ecological mystery. Absolutely. Thank you for 00:21:49.829 --> 00:21:51.730 joining us on this deep dive into the sources. 00:21:51.950 --> 00:21:54.210 Keep questioning those accepted paradigms, keep 00:21:54.210 --> 00:21:56.930 exploring the literature, and stay curious. We 00:21:56.930 --> 00:21:58.569 will see you on the next deep dive.