WEBVTT 00:00:00.000 --> 00:00:02.399 Welcome back to the Deep Dive. Today we are cracking 00:00:02.399 --> 00:00:05.719 open a cold case file from the prehistoric world. 00:00:05.900 --> 00:00:08.500 We're heading down underway, way down under, 00:00:08.580 --> 00:00:11.119 both in latitude and in time, to look at a creature 00:00:11.119 --> 00:00:13.740 with a name that, I have to be honest, sounds 00:00:13.740 --> 00:00:16.359 less like a scientific classification and more 00:00:16.359 --> 00:00:18.539 like a comic book supervillain. Or a really expensive 00:00:18.539 --> 00:00:22.539 piece of gaming hardware. Ultrastenos. Ultrastenos. 00:00:22.620 --> 00:00:24.899 It just sounds intense, doesn't it? Prepare to 00:00:24.899 --> 00:00:30.280 face the wrath of Ultrastenos. But as we've been 00:00:30.280 --> 00:00:31.760 combing through the source material for this 00:00:31.760 --> 00:00:34.159 dive, specifically some incredible detective 00:00:34.159 --> 00:00:36.219 work from the Queensland Museum involving researchers 00:00:36.219 --> 00:00:38.460 like Paul Willis, Adam Yates, and Michael Stein, 00:00:38.719 --> 00:00:40.920 it turns out this animal is actually a perfect 00:00:40.920 --> 00:00:44.060 case study in how messy paleontology really is. 00:00:44.179 --> 00:00:46.299 It really is. I mean, we tend to think of fossils 00:00:46.299 --> 00:00:48.799 as these immutable truths. You dig up a bone, 00:00:48.859 --> 00:00:50.420 you know what the animal looked like, end of 00:00:50.420 --> 00:00:53.570 story. But this story is all about... mistaken 00:00:53.570 --> 00:00:56.210 identity. It's about how we interpret broken 00:00:56.210 --> 00:00:59.130 fragments, how gravity and time can literally 00:00:59.130 --> 00:01:02.450 warp reality, and how a creature underwent this 00:01:02.450 --> 00:01:05.349 massive makeover. It went from being described 00:01:05.349 --> 00:01:07.969 as this needle -nosed, gharial -like specialist 00:01:07.969 --> 00:01:10.250 to something completely different, all because 00:01:10.250 --> 00:01:12.370 of how we interpret fractures and fossils. The 00:01:12.370 --> 00:01:14.549 total makeover story. But before we get to the 00:01:14.549 --> 00:01:17.129 twist, we need to ground ourselves. We are in 00:01:17.129 --> 00:01:20.150 the late Ligocene period. roughly, what, 28 to 00:01:20.150 --> 00:01:22.750 23 million years ago. Geographically, we're in 00:01:22.750 --> 00:01:25.510 northwestern Queensland, Australia, in the Riversley 00:01:25.510 --> 00:01:28.310 World Heritage Area. Now, I know Riversley is 00:01:28.310 --> 00:01:30.930 legendary in fossil circles, but set the scene 00:01:30.930 --> 00:01:33.629 for us. This isn't the dusty red outback we see 00:01:33.629 --> 00:01:36.969 in Mad Max. Oh, far from it. If you go to Riversley 00:01:36.969 --> 00:01:39.409 today, it's all spine -effects grass and blistering 00:01:39.409 --> 00:01:42.569 heat. But back in the oligocene, this was a lush, 00:01:42.609 --> 00:01:44.930 dynamic environment. We're talking about a karst 00:01:44.930 --> 00:01:48.310 landscape. So think limestone, porous rock full 00:01:48.310 --> 00:01:52.030 of holes, caves, and underground drainage systems. 00:01:52.450 --> 00:01:55.230 On the surface, you had open forests, but the 00:01:55.230 --> 00:01:57.250 water system was unique. It wasn't necessarily 00:01:57.250 --> 00:01:59.989 these massive, flowing river deltas like the 00:01:59.989 --> 00:02:02.730 Amazon. It was likely a system of forest lakes 00:02:02.730 --> 00:02:05.640 and ponds that were really rich in lime. And 00:02:05.640 --> 00:02:07.859 that lime is key, right? Because chemistry is 00:02:07.859 --> 00:02:10.599 kind of the unsung hero of paleontology. Absolutely. 00:02:11.060 --> 00:02:13.240 Limeridge water is basically a fossil factory. 00:02:13.400 --> 00:02:15.740 It coats the bones in calcium carbonate, essentially 00:02:15.740 --> 00:02:17.780 turning them into rock very quickly before they 00:02:17.780 --> 00:02:19.879 can rot away. That's why Riversley is one of 00:02:19.879 --> 00:02:21.680 the most important fossil sites on Earth. It 00:02:21.680 --> 00:02:23.199 preserves things that usually just disappear. 00:02:23.719 --> 00:02:25.939 And swimming in those limeridge ponds was the 00:02:25.939 --> 00:02:28.219 subject of our deep dive. So our mission today 00:02:28.219 --> 00:02:30.539 isn't just to list facts about a dead crocodile. 00:02:30.960 --> 00:02:33.240 We want to understand the detective work. We 00:02:33.240 --> 00:02:35.319 want to see how mistakes happen, how they get 00:02:35.319 --> 00:02:39.060 fixed, and, this is the crazy part, how two completely 00:02:39.060 --> 00:02:42.000 different fossil discoveries, separated by decades, 00:02:42.300 --> 00:02:44.879 turned out to be the exact same animal. That 00:02:44.879 --> 00:02:47.460 is the aha moment we're building towards. Let's 00:02:47.460 --> 00:02:48.900 get into the timeline, because this really does 00:02:48.900 --> 00:02:52.139 play out like a mystery novel. Section 1. A Tale 00:02:52.139 --> 00:02:55.020 of Two Fossils. The story really kicks off in 00:02:55.020 --> 00:02:58.780 1997. Right. In 1997, paleontologist Paul Willis 00:02:58.780 --> 00:03:02.560 is working at a spot in Riversley with the evocative 00:03:02.560 --> 00:03:05.280 name of the White Hunter site. I love the site 00:03:05.280 --> 00:03:07.379 names at Riversley, White Hunter, Low Lion. It 00:03:07.379 --> 00:03:09.539 just adds to that adventure vibe. It does. So 00:03:09.539 --> 00:03:12.080 at White Hunter, Willis finds a snout, just the 00:03:12.080 --> 00:03:14.500 front end of the animal. Now, looking at this 00:03:14.500 --> 00:03:17.180 snout, he sees it's heavy, it's robust, it looks 00:03:17.180 --> 00:03:19.219 like it's built for taking a beating. And based 00:03:19.219 --> 00:03:21.120 on that heaviness, he connected to a known group 00:03:21.120 --> 00:03:24.500 of Australian crocs called Baru. And Baru isn't 00:03:24.500 --> 00:03:27.240 exactly a delicate flower, is it? Not at all. 00:03:27.520 --> 00:03:30.159 Baru is often called the cleaver -headed crocodile. 00:03:30.560 --> 00:03:33.000 I mean, imagine a crocodile with a head shaped 00:03:33.000 --> 00:03:36.020 like a sledgehammer. Very heavy, very dangerous, 00:03:36.219 --> 00:03:39.639 massive crushing power. Willis thinks this new 00:03:39.639 --> 00:03:41.919 snout looks like a cousin of Garu, so he names 00:03:41.919 --> 00:03:45.139 it Baru Hooberry. Okay, so we have finding number 00:03:45.139 --> 00:03:49.319 one. Baru Hooberry. Heavy -built, typical crocodile 00:03:49.319 --> 00:03:52.280 vibe. But the sources mentioned there were other 00:03:52.280 --> 00:03:54.400 pieces found nearby that didn't quite fit the 00:03:54.400 --> 00:03:56.680 puzzle. Yes, and this is where the messiness 00:03:56.680 --> 00:03:58.900 of the field comes in. At that same site, they 00:03:58.900 --> 00:04:01.180 found some skull tables, you know, the flat top 00:04:01.180 --> 00:04:02.960 part of the head behind the eyes. They were found 00:04:02.960 --> 00:04:04.800 near the snout, but they didn't site together. 00:04:05.000 --> 00:04:07.919 There was missing bone in between. So as a scientist, 00:04:08.199 --> 00:04:10.219 Willis couldn't ethically say these definitely 00:04:10.219 --> 00:04:11.960 belong to the same animal. They just remained 00:04:11.960 --> 00:04:14.759 mystery pieces, just sitting in a museum drawer, 00:04:15.000 --> 00:04:17.579 labeled but unassigned. Waiting for their moment. 00:04:17.839 --> 00:04:19.839 Okay, fast forward almost 20 years. It's 2016. 00:04:20.490 --> 00:04:23.290 A different team, led by Michael Stein, is working 00:04:23.290 --> 00:04:25.910 at a different location, the Low Lion site. And 00:04:25.910 --> 00:04:28.730 they strike gold. They find a back of the skull 00:04:28.730 --> 00:04:31.649 and a lower jaw, a mandible. But when they look 00:04:31.649 --> 00:04:34.819 at this jaw, they see something shocking. The 00:04:34.819 --> 00:04:37.040 jawbones, they seem to converge really rapidly. 00:04:37.079 --> 00:04:39.660 They angle inward sharply, suggesting that the 00:04:39.660 --> 00:04:42.660 snout of this animal was incredibly long and 00:04:42.660 --> 00:04:46.139 thin. Like a pair of needle nose pliers or like 00:04:46.139 --> 00:04:49.620 those gharials you see in India. Exactly. A specialized 00:04:49.620 --> 00:04:53.019 pin thin snout. It looked so radically narrower 00:04:53.019 --> 00:04:55.600 than anything else found in Australia that they 00:04:55.600 --> 00:04:57.939 decided it needed a name to reflect that extreme 00:04:57.939 --> 00:05:00.720 anatomy. They combined the Latin ultra, meaning 00:05:00.720 --> 00:05:03.579 extreme, and the Greek stenos, meaning narrow. 00:05:04.079 --> 00:05:06.079 Ultrastinos, extreme narrow. And they named the 00:05:06.079 --> 00:05:08.939 species Ultrastinos willisi, honoring Paul Willis, 00:05:08.959 --> 00:05:12.079 ironically enough. So as of 2016, the scientific 00:05:12.079 --> 00:05:13.860 consensus was that we had two different animals. 00:05:14.120 --> 00:05:17.100 We had Bobby Hoobury from 1997, which was a heavy 00:05:17.100 --> 00:05:19.279 -duty cruncher, and Ultrastinos willisi from 00:05:19.279 --> 00:05:21.699 2016, which was this delicate, needle -nosed 00:05:21.699 --> 00:05:23.879 fish snatcher. Two different animals, two different 00:05:23.879 --> 00:05:26.180 ecological niches. One crushes, one snatches. 00:05:26.180 --> 00:05:28.689 That was the picture. Until 2024? This is where 00:05:28.689 --> 00:05:31.850 the plot twist happens. Adam Yates and Michael 00:05:31.850 --> 00:05:34.569 Stein publish a breakthrough paper. They decide 00:05:34.569 --> 00:05:36.490 to do some housekeeping on the collections and 00:05:36.490 --> 00:05:38.949 take a closer look at those old mystery pieces 00:05:38.949 --> 00:05:42.670 from 1997. Specifically, that skull fragment 00:05:42.670 --> 00:05:45.269 Willis had found but couldn't place. They took 00:05:45.269 --> 00:05:48.430 that piece and they took the original Baru -Huberi 00:05:48.430 --> 00:05:50.889 snout and they tried to fit them together again. 00:05:51.740 --> 00:05:54.459 It wasn't just a maybe. It was a lock. The edges 00:05:54.459 --> 00:05:57.279 were parallel. It turns out there was a fracture 00:05:57.279 --> 00:05:59.920 where the bone had broken apart, probably due 00:05:59.920 --> 00:06:02.639 to erosion or weathering before it was even collected. 00:06:03.000 --> 00:06:05.100 When you put them together, it wasn't just two 00:06:05.100 --> 00:06:07.079 animals of the same species. It was likely the 00:06:07.079 --> 00:06:09.560 same individual animal. That is just statistically 00:06:09.560 --> 00:06:12.060 wild. Yeah. I mean, think about the odds. You 00:06:12.060 --> 00:06:14.819 dig up a snout. Then decades later, you realize 00:06:14.819 --> 00:06:16.480 the back of the head was sitting in a drawer 00:06:16.480 --> 00:06:19.040 the whole time. It's the paleontological equivalent 00:06:19.040 --> 00:06:21.519 of finding the other sock in the dryer 20 years 00:06:21.519 --> 00:06:24.300 later. But this created a domino effect. Once 00:06:24.300 --> 00:06:26.800 they had the whole skull reconstructed, they 00:06:26.800 --> 00:06:28.680 could look at the ornamentation, the bumps and 00:06:28.680 --> 00:06:32.240 ridges on the bone. And guess what? That ornamentation 00:06:32.240 --> 00:06:36.360 matched the 2016 Ultrastinos finds perfectly. 00:06:36.819 --> 00:06:41.220 So Baru Huberi and Ultrastinos Willisi are the 00:06:41.220 --> 00:06:42.939 same animal. One and the same? But wait, they 00:06:42.939 --> 00:06:45.259 have different names. One is Baru, one is Ultrastinos, 00:06:45.379 --> 00:06:48.040 one is Huberi, one is Willisi. How do you decide 00:06:48.040 --> 00:06:50.220 what to call it? It sounds like a legal nightmare. 00:06:50.540 --> 00:06:54.019 It's less legal and more bureaucratic. We have 00:06:54.019 --> 00:06:55.720 to consult the rulebook, the International Code 00:06:55.720 --> 00:06:58.259 of Zoological Nomenclature. The core rule is 00:06:58.259 --> 00:07:00.399 generally priority. The first name published 00:07:00.399 --> 00:07:03.160 wins. So Huberi wins because it was from 1997. 00:07:03.579 --> 00:07:06.779 The species name Huberi wins, yes. But the genus 00:07:06.779 --> 00:07:09.180 name Baru was incorrect because this animal clearly 00:07:09.180 --> 00:07:11.899 wasn't a Baru. It was distinct enough to deserve 00:07:11.899 --> 00:07:15.120 its own genus. So the valid genus name is Ultrastanos, 00:07:15.220 --> 00:07:17.480 which was coined in 2016. So you just mash them 00:07:17.480 --> 00:07:20.279 together? You get Ultrastanos Huberi. And Ultrastanos 00:07:20.279 --> 00:07:24.079 Willisi. It becomes a junior synonym. It's essentially 00:07:24.079 --> 00:07:26.899 invalid now. It's a ghost name in the history 00:07:26.899 --> 00:07:30.720 books. But okay, we have a name. Ultrastanos 00:07:30.720 --> 00:07:33.879 Huberi. But this creates a huge problem, doesn't 00:07:33.879 --> 00:07:36.420 it? As we established, the name Ultrascanos means 00:07:36.420 --> 00:07:39.800 extreme narrow. Correct. But the 1997 snout, 00:07:39.879 --> 00:07:43.160 the hubiri part, was described as broad and short. 00:07:43.360 --> 00:07:47.160 And the 2016 jaw was described as extreme narrow. 00:07:47.980 --> 00:07:50.180 If they're the same animal, how can it be both 00:07:50.180 --> 00:07:53.060 broad and narrow? Did it have a shape -shifting 00:07:53.060 --> 00:07:55.000 face? And this is what we call the Pinocchio 00:07:55.000 --> 00:07:57.500 problem, or maybe the reverse Pinocchio. The 00:07:57.500 --> 00:07:59.319 name describes a feature the animal literally 00:07:59.319 --> 00:08:02.060 did not have. And this is where the science gets 00:08:02.060 --> 00:08:03.779 really interesting because it's about taphonomy, 00:08:03.939 --> 00:08:07.240 the study of how organisms decay and become fossilized. 00:08:07.339 --> 00:08:09.740 Let's dive into that because looking at a jaw 00:08:09.740 --> 00:08:11.579 and thinking it's needle thin when it's actually 00:08:11.579 --> 00:08:14.259 broad, that seems like a massive miss by the 00:08:14.259 --> 00:08:16.680 2016 team. How did that happen? Well, it comes 00:08:16.680 --> 00:08:18.860 down to the condition of the fossil. The 2016 00:08:18.860 --> 00:08:21.060 mandible, the lower jaw was broken. It wasn't 00:08:21.060 --> 00:08:23.160 attached to the skull. And crucially, the left 00:08:23.160 --> 00:08:25.860 jawbone was bent inward significantly more than 00:08:25.860 --> 00:08:28.279 the right one. Ah, so it was warped. Exactly. 00:08:28.439 --> 00:08:30.839 We call it plastic deformation. I mean, think 00:08:30.839 --> 00:08:33.360 about it. These bones are sitting in the ground 00:08:33.360 --> 00:08:37.860 for 25 million years. Rocks shift. pressure builds 00:08:37.860 --> 00:08:40.600 up. Even stone can warp if you give it enough 00:08:40.600 --> 00:08:43.179 time and pressure. It's like leaving a vinyl 00:08:43.179 --> 00:08:45.639 record in a hot car. It's still the record, but 00:08:45.639 --> 00:08:47.720 the shape changes. That's a great analogy. So 00:08:47.720 --> 00:08:50.539 the bone was kind of melted inward. In a geological 00:08:50.539 --> 00:08:53.340 sense, yeah. And when the researchers in 2016 00:08:53.340 --> 00:08:56.539 reconstructed it, that inward bend created an 00:08:56.539 --> 00:08:59.320 optical illusion. If you followed the angle of 00:08:59.320 --> 00:09:01.580 the bent bone, it looked like the jaws were converging 00:09:01.580 --> 00:09:04.320 into a super thin point. But in the 2024 revision, 00:09:04.600 --> 00:09:06.759 Yates and Stein realized that if you digitally 00:09:06.759 --> 00:09:09.379 unwarp, that bone rotated back to its natural 00:09:09.379 --> 00:09:11.799 position, it doesn't make a needle shape, it 00:09:11.799 --> 00:09:14.039 makes a U shape. So Ultrastinos, the extreme 00:09:14.039 --> 00:09:15.980 narrow crocodile, actually had a short, flat 00:09:15.980 --> 00:09:19.080 face. Ironically, yes. It was Platyrostral, flat 00:09:19.080 --> 00:09:21.639 -snouted, and Brevira strain, short -snouted. 00:09:21.899 --> 00:09:25.039 The name is now a permanent misnomer. It's named 00:09:25.039 --> 00:09:27.580 for a feature it never actually had. That is 00:09:27.580 --> 00:09:30.580 fantastic. It's like naming a dog spot and then 00:09:30.580 --> 00:09:33.860 realizing it has stripes. But surely the shape 00:09:33.860 --> 00:09:36.059 of the jaw isn't the only clue. If I'm trying 00:09:36.059 --> 00:09:37.799 to figure out what a crocodile eats, I'm looking 00:09:37.799 --> 00:09:39.740 at the teeth. And the teeth tell the real story 00:09:39.740 --> 00:09:42.399 here. This is why the long snout theory should 00:09:42.399 --> 00:09:44.779 have been suspicious from the start. Think about 00:09:44.779 --> 00:09:47.559 what a long -snouted crocodile eats. Gharials, 00:09:47.639 --> 00:09:50.500 for example. They are specialized fish traps. 00:09:50.679 --> 00:09:53.019 Right. They sweep that long, thin head through 00:09:53.019 --> 00:09:55.740 the water sideways to catch fast prey. Speed 00:09:55.740 --> 00:09:58.809 is key. And to catch a slippery, fast -moving 00:09:58.809 --> 00:10:01.549 fish, you need teeth that act like a cage. You 00:10:01.549 --> 00:10:04.070 need long, needle -like, interlocking teeth. 00:10:04.590 --> 00:10:07.149 Snap, and the fish is pinned. In ultrastinos. 00:10:07.330 --> 00:10:10.009 It didn't have needle teeth, it had malaria -formed 00:10:10.009 --> 00:10:11.789 teeth. Malaria -formed, like our molars. Similar 00:10:11.789 --> 00:10:14.529 function. They were low, rounded, and robust 00:10:14.529 --> 00:10:17.450 buttons of bone. These aren't for piercing, they 00:10:17.450 --> 00:10:19.909 are for crushing. If you tried to catch a fast 00:10:19.909 --> 00:10:21.490 -moving fish with these teeth, it would just 00:10:21.490 --> 00:10:24.309 slip out like a wet bar of soap. These teeth 00:10:24.309 --> 00:10:26.230 are built for high pressure. They are built to 00:10:26.230 --> 00:10:28.570 crunch through shells, bones, and armor. So we 00:10:28.570 --> 00:10:31.610 have a short -faced, crunching crocodile. Paint 00:10:31.610 --> 00:10:34.009 a picture for me. What did this thing look like 00:10:34.009 --> 00:10:36.570 when it was alive? Was it big? Surprisingly small. 00:10:36.629 --> 00:10:39.509 We're talking about 1 .5 meters, maybe 5 feet 00:10:39.509 --> 00:10:42.470 long. Similar in size to a modern Australian 00:10:42.470 --> 00:10:45.710 freshwater crocodile. So relatively cute -sized. 00:10:45.870 --> 00:10:48.179 Relatively. And it had some distinct features. 00:10:48.419 --> 00:10:50.659 The nostrils were right at the tip of the snout, 00:10:50.679 --> 00:10:54.360 facing slightly forward. And the eyes, this is 00:10:54.360 --> 00:10:57.779 interesting, it had very large teardrop -shaped 00:10:57.779 --> 00:11:00.480 openings on top of the skull called supratemporal 00:11:00.480 --> 00:11:03.759 fenestri. Teardrop eyes. Sounds poetic, but I 00:11:03.759 --> 00:11:05.399 assume those holes are for muscles. Exactly. 00:11:05.600 --> 00:11:08.379 The fact that those openings were so huge suggests 00:11:08.379 --> 00:11:11.679 massive jaw muscles. This animal had a very powerful 00:11:11.679 --> 00:11:14.220 bite for its size. And the jawline wasn't straight. 00:11:14.259 --> 00:11:17.649 It had... Fistoons? Fistoons. Like party decorations. 00:11:17.889 --> 00:11:20.409 Like waves. The tooth row curved up and down, 00:11:20.470 --> 00:11:22.169 which again helps with holding onto prey that 00:11:22.169 --> 00:11:24.389 you're trying to crush. It creates locking points 00:11:24.389 --> 00:11:26.629 so the hard shell doesn't slide out. Okay, so 00:11:26.629 --> 00:11:29.950 we have a clear avatar now. Small, five -foot, 00:11:30.049 --> 00:11:33.309 short -faced, muscle -headed crocodile with crushing 00:11:33.309 --> 00:11:36.149 teeth. Let's talk about its life. You mentioned 00:11:36.149 --> 00:11:38.049 Riversley wasn't a desert then, but it wasn't 00:11:38.049 --> 00:11:40.649 exactly a massive river delta either. No, the 00:11:40.649 --> 00:11:43.610 low lion site where the 2016 fossil was found 00:11:43.610 --> 00:11:46.610 was likely open forest. It was a karst system, 00:11:46.710 --> 00:11:49.009 lakes and ponds that drained through limestone. 00:11:49.250 --> 00:11:51.909 And these water bodies might not have been permanent. 00:11:52.049 --> 00:11:54.909 Exactly. Like modern freshwater crocs, Ultrastinos 00:11:54.909 --> 00:11:57.149 might have had to deal with water levels dropping 00:11:57.149 --> 00:12:00.230 or ponds drying up seasonally. It had to be adaptable. 00:12:00.309 --> 00:12:02.529 It wasn't alone, right? I imagine 25 million 00:12:02.529 --> 00:12:05.299 years ago. Australia had some scary wildlife. 00:12:05.559 --> 00:12:08.039 Oh, absolutely. Ultrastinos was living alongside 00:12:08.039 --> 00:12:10.820 giants. At the White Hunter site, it coexisted 00:12:10.820 --> 00:12:13.440 with Baru Wikene. That's the real Baru. The real 00:12:13.440 --> 00:12:16.039 deal. And Baru Wikene was massive, heavily built, 00:12:16.139 --> 00:12:19.179 a top predator. If Ultrastinos is a compact car... 00:12:19.480 --> 00:12:21.960 Baru is a semi -truck. So how does a five -foot 00:12:21.960 --> 00:12:24.759 Ultrastinos survive next to a Jai Baru? Niche 00:12:24.759 --> 00:12:26.960 partitioning. Basically staying out of the way 00:12:26.960 --> 00:12:29.480 and eating different things. Ultrastinos was 00:12:29.480 --> 00:12:32.159 the underdog. It was small enough to hide in 00:12:32.159 --> 00:12:34.279 the shallows or the denser vegetation where the 00:12:34.279 --> 00:12:37.340 big Baru couldn't go. And the diet. You said 00:12:37.340 --> 00:12:38.799 it wasn't eating vats because of those crushing 00:12:38.799 --> 00:12:41.120 teeth. That's the current theory. Originally, 00:12:41.120 --> 00:12:43.200 when they thought it had a long snout, they assumed 00:12:43.200 --> 00:12:45.980 it was a piscivore, a fish eater. But now... 00:12:46.409 --> 00:12:49.289 With the short snout and crushing teeth, plus 00:12:49.289 --> 00:12:51.450 the fact that fish fossils are actually surprisingly 00:12:51.450 --> 00:12:54.470 rare in that specific part of Riversley for that 00:12:54.470 --> 00:12:58.840 time period. Wait, rare fish fossils? In a lake 00:12:58.840 --> 00:13:01.139 system? That seems counterintuitive. It does 00:13:01.139 --> 00:13:03.200 happen. Sometimes the chemistry doesn't preserve 00:13:03.200 --> 00:13:05.700 them, or maybe the ponds were isolated and seasonal, 00:13:05.720 --> 00:13:07.899 so fish populations just couldn't get established. 00:13:08.259 --> 00:13:11.220 But because of the teeth and that scarcity, the 00:13:11.220 --> 00:13:13.620 new theory is that Ultrastinos was eating small 00:13:13.620 --> 00:13:17.799 land animals. Frogs, snakes, birds, maybe small 00:13:17.799 --> 00:13:21.600 mammals. Crunchy snacks. Exactly. Snails, crustaceans, 00:13:21.600 --> 00:13:23.529 anything it could grab and crush. This brings 00:13:23.529 --> 00:13:25.409 up a really fascinating point that the source 00:13:25.409 --> 00:13:28.350 has highlighted. It's what they call the implications 00:13:28.350 --> 00:13:31.889 for mecosuchinae. And this leads us to the mystery 00:13:31.889 --> 00:13:35.629 of the ghost niche. I love this concept. So mecosuchinae 00:13:35.629 --> 00:13:38.649 is the group Ultrastinos belongs to. It's a specific 00:13:38.649 --> 00:13:41.850 group of extinct crocodiles from Australia and 00:13:41.850 --> 00:13:44.350 the South Pacific. And here's the weird thing. 00:13:44.879 --> 00:13:47.139 Unlike croc families in the rest of the world, 00:13:47.679 --> 00:13:50.740 Mekosuchines never really evolved that classic, 00:13:50.840 --> 00:13:53.759 long -snouted, gharial -like shape. Which is 00:13:53.759 --> 00:13:55.100 strange, right, because if you look at South 00:13:55.100 --> 00:13:58.639 America, Africa, indialong snouts pop up everywhere. 00:13:58.779 --> 00:14:01.200 It's a great design for catching fish. It's a 00:14:01.200 --> 00:14:03.200 very successful design. Convergent evolution 00:14:03.200 --> 00:14:06.639 usually makes it happen. But in Australia, nothing. 00:14:06.980 --> 00:14:08.779 And Ultracinos was supposed to be the answer. 00:14:09.210 --> 00:14:11.129 It was supposed to be the missing link that proved 00:14:11.129 --> 00:14:13.490 Australian Crocs did do it. Exactly. It was the 00:14:13.490 --> 00:14:15.529 one exception. But now that we know Ultrastinos 00:14:15.529 --> 00:14:18.190 actually had a short snout, well, the exception 00:14:18.190 --> 00:14:20.870 is gone. The mystery is back. Why not? Is there 00:14:20.870 --> 00:14:22.990 something about Australia that just hates long 00:14:22.990 --> 00:14:26.309 snouts? There are a few theories. One is developmental 00:14:26.309 --> 00:14:29.019 constraints. Maybe their genes just wouldn't 00:14:29.019 --> 00:14:31.639 allow that shake to form easily, similar to how 00:14:31.639 --> 00:14:34.240 modern alligators rarely get super narrow snouts. 00:14:34.580 --> 00:14:37.220 But the more compelling theory ties back to the 00:14:37.220 --> 00:14:40.340 environment. The drying continent. Exactly. If 00:14:40.340 --> 00:14:42.759 the water bodies in Australia were becoming more 00:14:42.759 --> 00:14:45.320 seasonal, drying up into mud puddles every year, 00:14:45.399 --> 00:14:47.960 being a specialized fish eater is a risky strategy. 00:14:48.379 --> 00:14:50.960 If the fill die out when the pond shrinks, you 00:14:50.960 --> 00:14:53.740 starve. So you need to be a generalist. You need 00:14:53.740 --> 00:14:56.559 to be a Swiss army knife, not a scalpel. Precisely. 00:14:56.840 --> 00:14:58.919 If you have a short, broad snout, you can eat 00:14:58.919 --> 00:15:00.639 a fish if you find one, but you can also eat 00:15:00.639 --> 00:15:03.519 a wallaby or a frog or a snail. You survive the 00:15:03.519 --> 00:15:05.480 bad times. So maybe the Australian landscape 00:15:05.480 --> 00:15:08.779 itself forced these crocodiles to stay generalists. 00:15:08.980 --> 00:15:11.279 It's the ghost of a niche that nobody could afford 00:15:11.279 --> 00:15:14.519 to fill. That is such a cool concept. It frames 00:15:14.519 --> 00:15:16.820 evolution not just as what is the best design, 00:15:16.940 --> 00:15:19.100 but what is the safest bet. And in Australia, 00:15:19.179 --> 00:15:21.840 the safe bet is usually adaptability. Let's quickly 00:15:21.840 --> 00:15:23.899 look at the family reunion before we wrap up. 00:15:23.980 --> 00:15:26.940 We established it's a Mekosushin. Is it related 00:15:26.940 --> 00:15:29.600 to the modern saltwater crocs we see in Darwin 00:15:29.600 --> 00:15:32.000 today? No, and that's a common misconception. 00:15:32.179 --> 00:15:35.120 The salties and freshies in Australia today are 00:15:35.120 --> 00:15:37.980 relatively new arrivals, immigrants from Asia 00:15:37.980 --> 00:15:39.919 that came over in the last few million years. 00:15:40.679 --> 00:15:43.460 Ultrastinos and its kin are the original Australians. 00:15:43.500 --> 00:15:46.159 They were there for tens of millions of years 00:15:46.159 --> 00:15:48.580 before the modern crocs showed up. And despite 00:15:48.580 --> 00:15:52.000 the old name Baru Huberi, It's not closely related 00:15:52.000 --> 00:15:54.899 to the giant Baru, right? No, they are distant 00:15:54.899 --> 00:15:57.779 cousins within the Mecosuchin group. Ultrastinos 00:15:57.779 --> 00:16:00.139 sits on a different branch. It's actually closely 00:16:00.139 --> 00:16:01.879 related to a creature we haven't even officially 00:16:01.879 --> 00:16:05.039 named yet, referred to in the papers as the Bullet 00:16:05.039 --> 00:16:07.960 Creek taxon. The Bullet Creek taxon sounds like 00:16:07.960 --> 00:16:10.279 an X -file. It does, and it's also on the branch 00:16:10.279 --> 00:16:12.940 with the dwarf Mecosuchins, animals like Trilophosuchus 00:16:12.940 --> 00:16:15.720 and Mecosuchus. Trilophosuchus is that tiny land 00:16:15.720 --> 00:16:17.200 croc, right? The one that looked like a little 00:16:17.200 --> 00:16:20.100 lizard. That's the one. So Ultrastinos confirms 00:16:20.100 --> 00:16:22.639 that there was this distinct lineage of small 00:16:22.639 --> 00:16:25.059 -bodied, short -snouted crocs evolving right 00:16:25.059 --> 00:16:27.120 alongside the giants. They weren't just baby 00:16:27.120 --> 00:16:28.940 giants. They were their own thing, doing their 00:16:28.940 --> 00:16:31.820 own evolutionary experiment. So what does this 00:16:31.820 --> 00:16:34.220 all mean? We've gone from a comic book villain 00:16:34.220 --> 00:16:37.240 name to a tale of two fossils, a glue job that 00:16:37.240 --> 00:16:41.080 solved a 20 -year cold case, and a total anatomical 00:16:41.080 --> 00:16:43.179 re -imaging. I think the biggest takeaway is 00:16:43.179 --> 00:16:46.159 scientific humility. The name Ultrastinos, extreme 00:16:46.159 --> 00:16:48.799 narrow, will likely stay. It's the official valid 00:16:48.799 --> 00:16:51.759 name. But it describes a feature the animal didn't 00:16:51.759 --> 00:16:55.529 have. It is a permanent, Latinized reminder that 00:16:55.529 --> 00:16:57.889 we can get things wrong. It's honest, though. 00:16:57.990 --> 00:17:00.110 It is. It shows science working as intended. 00:17:00.470 --> 00:17:03.070 New evidence comes to light. In this case, Yates 00:17:03.070 --> 00:17:04.990 and Stein realizing those fractures matched, 00:17:05.210 --> 00:17:07.769 and we correct the old assumptions. We don't 00:17:07.769 --> 00:17:09.990 stick to the old idea just because we liked the 00:17:09.990 --> 00:17:12.930 name or the cool factor of a long snout. And 00:17:12.930 --> 00:17:14.710 it reminds us that saucels aren't just rocks. 00:17:14.950 --> 00:17:17.630 They were living things that broke, decayed, 00:17:17.630 --> 00:17:21.089 and got squished over millions of years. Reconstructing 00:17:21.089 --> 00:17:23.940 them is really hard work. It's a 3D puzzle where 00:17:23.940 --> 00:17:25.920 half the pieces are missing and the ones you 00:17:25.920 --> 00:17:28.359 have are bent. Before we wrap up, I want to leave 00:17:28.359 --> 00:17:30.059 you with a final thought on that ghost niche. 00:17:30.700 --> 00:17:33.619 Long -snouted crocodiles appear almost everywhere 00:17:33.619 --> 00:17:37.319 else in the world. They are efficient, but not 00:17:37.319 --> 00:17:40.180 here. Not here. If Ultrastinos wasn't the one 00:17:40.180 --> 00:17:43.519 and the Mecasuchines never did it, is there something 00:17:43.519 --> 00:17:46.079 about the Australian landscape itself that is 00:17:46.079 --> 00:17:49.380 fundamentally hostile to specialization? Is the 00:17:49.380 --> 00:17:51.579 hydrology of the continent, the way the water 00:17:51.579 --> 00:17:54.279 flows and dries up, so harsh that becoming a 00:17:54.279 --> 00:17:57.440 specialized fish eater is a death sentence? It's 00:17:57.440 --> 00:17:59.759 a fascinating question. Did the drying of the 00:17:59.759 --> 00:18:01.960 continent kill off the potential for that lifestyle 00:18:01.960 --> 00:18:05.440 before it could even start? Or is there a fossil 00:18:05.440 --> 00:18:08.000 out there, still waiting in a limestone block 00:18:08.000 --> 00:18:10.259 at Riversley, that will prove us wrong again? 00:18:10.539 --> 00:18:12.839 Maybe we'll find the real Ultrastinos one day. 00:18:13.099 --> 00:18:16.980 But for now, we have Ultrastinos Uberi. The short 00:18:16.980 --> 00:18:19.099 -snotted crocodile with the ironically extreme 00:18:19.099 --> 00:18:22.779 name. A small croc with a big story. Thanks for 00:18:22.779 --> 00:18:24.779 diving deep with us. Keep questioning what you 00:18:24.779 --> 00:18:26.980 see in the museums. Sometimes the labels only 00:18:26.980 --> 00:18:28.839 have the story. See you next time. Catch you 00:18:28.839 --> 00:18:29.619 on the next deep dive.