WEBVTT 00:00:00.000 --> 00:00:01.860 Okay, let's get into this. I want you to picture 00:00:01.860 --> 00:00:04.719 a name. A name that sounds like, I don't know, 00:00:04.839 --> 00:00:08.039 something a toddler made up to describe a monster. 00:00:08.400 --> 00:00:10.539 Or maybe something from a cheesy B -movie. Exactly. 00:00:11.320 --> 00:00:13.400 Jaganotosaurus. I mean, it literally translates 00:00:13.400 --> 00:00:19.339 to giant southern lizard. It just sounds so on 00:00:19.339 --> 00:00:21.600 the nose, a little fake. It does have a certain 00:00:21.600 --> 00:00:23.539 lack of subtlety, doesn't it? Like a marketing 00:00:23.539 --> 00:00:27.260 team came up with it. But for all the heavy -handedness 00:00:27.260 --> 00:00:30.320 of the name, this was a very real... Very massive 00:00:30.320 --> 00:00:32.979 animal. And that's the thing. For so long, the 00:00:32.979 --> 00:00:34.759 public consciousness has been totally dominated 00:00:34.759 --> 00:00:37.140 by just one king of the dinosaurs. Oh, absolutely. 00:00:37.420 --> 00:00:40.119 Tyrannosaurus Rex. It's on the lunchboxes, the 00:00:40.119 --> 00:00:43.780 bedsheets, all the movies. the undisputed heavyweight 00:00:43.780 --> 00:00:45.520 champion of the world. Well, today we're going 00:00:45.520 --> 00:00:47.159 to challenge that title a little bit. We are. 00:00:47.179 --> 00:00:50.740 We're heading south, way down south to Patagonia, 00:00:50.759 --> 00:00:52.899 Argentina. And we're going back in time specifically 00:00:52.899 --> 00:00:55.960 to the late Cretaceous period, the early Cenomanian 00:00:55.960 --> 00:00:58.619 age. So we're talking about a window of roughly, 00:00:58.719 --> 00:01:02.840 say, 99 to 95 million years ago. And that's a 00:01:02.840 --> 00:01:05.280 key distinction, isn't it? The world was a different 00:01:05.280 --> 00:01:08.079 place. A very different place. This is Don Juana 00:01:08.079 --> 00:01:09.700 we're talking about, the southern supercontinent. 00:01:09.840 --> 00:01:12.439 The dinosaur evolution happening there was totally 00:01:12.439 --> 00:01:14.840 separate from the North American story we all 00:01:14.840 --> 00:01:16.920 grew up on. So that's our mission for this deep 00:01:16.920 --> 00:01:19.379 dive. We're unpacking the story of Giganotosaurus. 00:01:19.780 --> 00:01:22.079 We'll get into how it was found. And that involves 00:01:22.079 --> 00:01:24.120 a dune buggy, which is my favorite part. It's 00:01:24.120 --> 00:01:26.400 a great detail. And then the huge scientific 00:01:26.400 --> 00:01:29.000 brawl over whether it was actually bigger than 00:01:29.000 --> 00:01:33.120 T. rex. And the... the really surprising engineering 00:01:33.120 --> 00:01:35.420 inside its skull because this thing was built 00:01:35.420 --> 00:01:37.980 like a biological slicing machine. It truly was. 00:01:38.219 --> 00:01:40.640 And what's so fascinating is that Giganotosaurus 00:01:40.640 --> 00:01:44.250 represents a completely different. evolutionary 00:01:44.250 --> 00:01:47.390 answer to the question, how do you become a giant 00:01:47.390 --> 00:01:49.769 apex predator? Two different solutions to the 00:01:49.769 --> 00:01:52.730 same problem. Exactly. Nature solved it one way 00:01:52.730 --> 00:01:54.510 in the north and a very different way in the 00:01:54.510 --> 00:01:56.390 south. Okay, let's start with that discovery 00:01:56.390 --> 00:01:58.750 story because I love it when these huge scientific 00:01:58.750 --> 00:02:01.150 moments happen in just the most random way. It's 00:02:01.150 --> 00:02:04.450 1993. We're in the Badlands near a place called 00:02:04.450 --> 00:02:07.629 Villa El Chocon in Patagonia. And there's this 00:02:07.629 --> 00:02:11.030 guy, Ruben Dario Carolini. Now, usually when 00:02:11.030 --> 00:02:14.210 you hear about these major finds, it's some tenured 00:02:14.210 --> 00:02:17.409 professor leading a huge expedition. Right, with 00:02:17.409 --> 00:02:19.710 a whole team of grad students and ground -penetrating 00:02:19.710 --> 00:02:23.629 radar and all that. But Carolini, he's a mechanic, 00:02:23.830 --> 00:02:28.030 an amateur fossil hunter, and he's just out for 00:02:28.030 --> 00:02:30.409 a drive. In a dune buggy. In a dune buggy. You 00:02:30.409 --> 00:02:32.750 have to love that image. He's just cruising through 00:02:32.750 --> 00:02:35.939 the Badlands, and he spots a bone. Just, you 00:02:35.939 --> 00:02:37.759 know, sticking out of the ground. A tibia. Right. 00:02:37.860 --> 00:02:40.340 A lower leg bone. A tibia. And he knows it's 00:02:40.340 --> 00:02:43.060 something big. But I really doubt he knew he'd 00:02:43.060 --> 00:02:45.539 just stumbled on one of the most important paleontological 00:02:45.539 --> 00:02:48.159 finds of the century. So he does the right thing. 00:02:48.180 --> 00:02:50.199 He calls in the professionals. Yep. Specialists 00:02:50.199 --> 00:02:51.900 from the National University come. He show up. 00:02:52.159 --> 00:02:54.759 And what they uncovered was just remarkable, 00:02:55.060 --> 00:02:57.520 not just for its size, but for how complete it 00:02:57.520 --> 00:02:59.900 was. They found a specimen that was almost 70 00:02:59.900 --> 00:03:01.930 percent complete. And we should pause on that. 00:03:02.030 --> 00:03:04.930 I mean, 70 % might sound like a C - on a test, 00:03:05.110 --> 00:03:08.310 but for a giant theropod, that is a lottery ticket, 00:03:08.509 --> 00:03:10.969 an absolute grand prize. Why is it so rare to 00:03:10.969 --> 00:03:14.590 find one so complete? Well, think about it. Apex 00:03:14.590 --> 00:03:17.689 predators are rare in an ecosystem to begin with. 00:03:18.150 --> 00:03:20.569 You have way more herbivores than carnivores. 00:03:20.629 --> 00:03:23.930 Sure, like lions and zebras. Exactly. And then 00:03:23.930 --> 00:03:26.650 for one to die in just the right spot to fossilize 00:03:26.650 --> 00:03:29.669 perfectly? It almost never happens. Usually you 00:03:29.669 --> 00:03:31.889 find a tooth, maybe a vertebra if you're lucky. 00:03:32.090 --> 00:03:34.530 But here they had the spine, the girdles, the 00:03:34.530 --> 00:03:37.509 femurs. A whole lower leg. Yeah. The skull was 00:03:37.509 --> 00:03:39.169 a bit of a puzzle. It was scattered over about 00:03:39.169 --> 00:03:41.810 10 square meters. But they had enough to piece 00:03:41.810 --> 00:03:43.849 together a monster. And of course they had to 00:03:43.849 --> 00:03:45.930 name it after the guy in the dune buggy. They 00:03:45.930 --> 00:03:49.810 did. In 1995, paleontologists Rodolfo Correa 00:03:49.810 --> 00:03:52.270 and Leonardo Salgado officially published their 00:03:52.270 --> 00:03:55.389 description. Giga's for giant, Nodo's for southern, 00:03:55.770 --> 00:03:59.219 Soro's for lizard. And the species name. Carolene. 00:03:59.340 --> 00:04:01.860 In honor of Ruben Carolene. It's a great tribute. 00:04:01.900 --> 00:04:03.979 And you can still see it today, right? The original 00:04:03.979 --> 00:04:06.759 specimen. You can. It's the main exhibit at the 00:04:06.759 --> 00:04:09.759 Ernesto Bachmann Paleontological Museum. And 00:04:09.759 --> 00:04:12.360 they have it displayed on a sandy floor with 00:04:12.360 --> 00:04:14.259 the original excavation tools right there with 00:04:14.259 --> 00:04:16.259 it. It's a really cool touch. It really grounds 00:04:16.259 --> 00:04:18.160 it. You know, it shows the human effort that 00:04:18.160 --> 00:04:21.120 went into it. It does. But almost as soon as 00:04:21.120 --> 00:04:23.839 that paper came out in 95, the comparison started. 00:04:24.220 --> 00:04:26.800 And that brings us to the big controversy. The 00:04:26.800 --> 00:04:29.660 heavyweight title fight. Giganotosaurus versus 00:04:29.660 --> 00:04:33.199 T -Rex. The main event. So when Corey and Salgado 00:04:33.199 --> 00:04:35.360 first described it, they didn't pull any punches. 00:04:35.420 --> 00:04:37.639 They pointed straight at the femur, the thigh 00:04:37.639 --> 00:04:41.379 bone. It was 1 .43 meters long. Which is about 00:04:41.379 --> 00:04:44.100 5 centimeters longer than the femur of Sue. And 00:04:44.100 --> 00:04:46.920 Sue is the biggest, most famous T -Rex specimen 00:04:46.920 --> 00:04:49.360 we have. Exactly. So that 5 centimeters is just 00:04:49.360 --> 00:04:52.259 2 inches. That was the first shot fired. So does 00:04:52.259 --> 00:04:55.019 a slightly longer leg bone... automatically mean 00:04:55.019 --> 00:04:57.639 it's a bigger dinosaur overall well that was 00:04:57.639 --> 00:04:59.720 the initial thinking the first estimates put 00:04:59.720 --> 00:05:02.660 giganotosaurus at about 12 .5 meters long so 00:05:02.660 --> 00:05:05.959 41 feet and somewhere between six to eight tons 00:05:05.959 --> 00:05:08.620 okay so that puts it squarely in the t -rex weight 00:05:08.620 --> 00:05:11.639 class a real contender a contender for sure but 00:05:11.639 --> 00:05:13.899 then Things got a little more complicated. Another 00:05:13.899 --> 00:05:16.560 fossil entered the chat, so to speak. It did. 00:05:16.699 --> 00:05:19.480 A partial jawbone, a dentary, that was actually 00:05:19.480 --> 00:05:22.060 found earlier by a paleontologist named Jorge 00:05:22.060 --> 00:05:24.579 Calvo. Found in 87, but they didn't know what 00:05:24.579 --> 00:05:27.480 it was at first. Right. It wasn't assigned to 00:05:27.480 --> 00:05:31.579 Giganotosaurus until 1998. Calvo and Coria looked 00:05:31.579 --> 00:05:33.939 at it and realized it was identical to the original 00:05:33.939 --> 00:05:36.689 specimen's jaw. Except for one thing. It was 00:05:36.689 --> 00:05:39.810 bigger. It was 8 % larger. 8%. So they just did 00:05:39.810 --> 00:05:42.009 the math and scaled up the whole animal? That 00:05:42.009 --> 00:05:44.310 was the extrapolation, yeah. If you scale up 00:05:44.310 --> 00:05:47.610 the entire skull based on that one jawbone, you 00:05:47.610 --> 00:05:51.230 get a skull that is 1 .95 meters long. That's 00:05:51.230 --> 00:05:54.029 over 6 feet. Just the head. Just the head. You 00:05:54.029 --> 00:05:55.689 could practically stand up inside its mouth. 00:05:55.990 --> 00:05:58.189 And that pushed the total body length estimate 00:05:58.189 --> 00:06:01.290 up to 13 .2 meters. Suddenly, T -Rex is looking 00:06:01.290 --> 00:06:03.629 over its shoulder. I can just imagine the T -Rex 00:06:03.629 --> 00:06:06.009 fans were not happy about this. People get very 00:06:06.009 --> 00:06:07.930 protective of their favorite dinosaur. Oh, not 00:06:07.930 --> 00:06:10.990 at all. This sparked a decades -long scientific 00:06:10.990 --> 00:06:14.009 back and forth. You had paleontologist Paul Serino, 00:06:14.069 --> 00:06:16.089 for example, arguing that it's really hard to 00:06:16.089 --> 00:06:19.189 judge true size from incomplete skeletons. Fair 00:06:19.189 --> 00:06:20.990 enough. But then other estimates came out that 00:06:20.990 --> 00:06:24.069 were even bigger. In 2007, yeah. Researchers 00:06:24.069 --> 00:06:26.129 Therian and Henderson tried a different method. 00:06:26.490 --> 00:06:29.009 They used skull length to estimate body weight. 00:06:29.129 --> 00:06:31.730 And because Giganotosaurus has such a long skull, 00:06:32.050 --> 00:06:35.529 their math came out with a weight of 13 .8 tons. 00:06:35.790 --> 00:06:39.009 13 .8 tons. That's almost double the first estimate. 00:06:39.069 --> 00:06:41.829 That's like two elephants. That's massive. But 00:06:41.829 --> 00:06:43.829 that study had its critics. Because you have 00:06:43.829 --> 00:06:45.589 to remember what family this animal belongs to. 00:06:45.850 --> 00:06:48.550 The carcharodontosaurus. Exactly. And they naturally 00:06:48.550 --> 00:06:50.829 have longer, somewhat lighter skulls compared 00:06:50.829 --> 00:06:53.810 to the big, boxy, heavy head of a tyrannosaur. 00:06:54.170 --> 00:06:56.569 So if you use skull length as your only metric 00:06:56.569 --> 00:06:58.850 for weight. It might skew the results. It's like 00:06:58.850 --> 00:07:00.949 judging a person's weight by how tall their hat 00:07:00.949 --> 00:07:02.649 is. That's a little bit of a stretch. But yeah, 00:07:02.689 --> 00:07:04.209 the proportions matter. You can't just apply 00:07:04.209 --> 00:07:06.610 one formula to different families. So then someone 00:07:06.610 --> 00:07:08.649 else came along and argued the other way. In 00:07:08.649 --> 00:07:11.569 2013, Scott Hartman, who's famous for his incredibly 00:07:11.569 --> 00:07:15.120 detailed skeletal drawings, he weighed in. He 00:07:15.120 --> 00:07:17.500 argued that while Giganotosaurus might be longer, 00:07:17.819 --> 00:07:20.819 T. rex was wider. Wider. You mean like barrel 00:07:20.819 --> 00:07:24.579 -chested. Precisely. The torso width. Hartman's 00:07:24.579 --> 00:07:26.879 take was that T. rex was built like a beer keg 00:07:26.879 --> 00:07:30.879 on legs. Just thick, heavy, robust. While Giganotosaurus 00:07:30.879 --> 00:07:33.459 was maybe a bit slimmer. More athletic, yeah. 00:07:33.579 --> 00:07:37.000 He put Giga back down in that 6 .8 to 8 .2 ton 00:07:37.000 --> 00:07:40.300 range. So T. rex is the linebacker and Giganotosaurus 00:07:40.300 --> 00:07:42.740 is the NBA center. That's a great analogy. It 00:07:42.740 --> 00:07:44.730 really depends on how you define bigger. Is it 00:07:44.730 --> 00:07:47.709 length? Is it weight? Is it volume? And just 00:07:47.709 --> 00:07:50.910 to muddy the waters even more, we now have Spinosaurus. 00:07:51.129 --> 00:07:54.810 Ah, yes. Spinosaurus, the wild card. Generally 00:07:54.810 --> 00:07:57.170 accepted as the longest theropod now, maybe over 00:07:57.170 --> 00:08:00.029 15 meters. But it's a semi -aquatic fish eater, 00:08:00.129 --> 00:08:02.029 a totally different kind of animal. So where 00:08:02.029 --> 00:08:04.949 does the consensus land today? The consensus 00:08:04.949 --> 00:08:07.170 is that Giganotosaurus is absolutely one of the 00:08:07.170 --> 00:08:10.470 largest land carnivores ever. It likely rivaled 00:08:10.470 --> 00:08:13.350 or slightly exceeded T. rex in length, even if 00:08:13.350 --> 00:08:15.310 the mass estimates are still all over the place, 00:08:15.370 --> 00:08:18.850 from 4 tons to nearly 14. Right. Regardless of 00:08:18.850 --> 00:08:20.810 the exact number, if one of these walked past 00:08:20.810 --> 00:08:23.189 your window, you would not be getting out a tape 00:08:23.189 --> 00:08:25.029 measure. You'd be hiding in the basement. You 00:08:25.029 --> 00:08:26.490 wouldn't be arguing about centimeters, that's 00:08:26.490 --> 00:08:28.509 for sure. Okay, but let's move past just the 00:08:28.509 --> 00:08:31.189 size. Because for me, the coolest part is the 00:08:31.189 --> 00:08:34.379 hardware. You mentioned the skull shape. T -Rex 00:08:34.379 --> 00:08:37.799 is famous for its bone -crushing bite. The bone 00:08:37.799 --> 00:08:41.200 crusher, yes. Thick, almost banana -shaped teeth 00:08:41.200 --> 00:08:44.419 designed to withstand incredible pressure. It 00:08:44.419 --> 00:08:48.080 pulverizes bone to get to the marrow. Giganotosaurus 00:08:48.080 --> 00:08:50.399 was engineered completely differently. It had 00:08:50.399 --> 00:08:54.049 that low, long skull. Low and long, yeah. But 00:08:54.049 --> 00:08:55.850 it wasn't built for crushing. It was built for 00:08:55.850 --> 00:08:57.769 slicing. Slicing. If you look at the teeth, they 00:08:57.769 --> 00:09:00.250 aren't round cones. They're compressed sideways, 00:09:00.490 --> 00:09:03.250 serrated. They're like steak knives. A very large, 00:09:03.429 --> 00:09:06.049 very messy surgical instrument. Exactly. The 00:09:06.049 --> 00:09:07.809 whole design suggests it would slice through 00:09:07.809 --> 00:09:10.490 flesh, cause massive soft tissue damage, not 00:09:10.490 --> 00:09:12.730 pulverize the skeleton. And it had this very 00:09:12.730 --> 00:09:16.049 peculiar feature on its lower jaw. A chin. A 00:09:16.049 --> 00:09:18.669 chin, like a superhero chin. Sort of. The very 00:09:18.669 --> 00:09:20.649 front of the lower jaw was flattened and had 00:09:20.649 --> 00:09:22.669 this downward projecting process. We call it 00:09:22.669 --> 00:09:25.240 a chin. The leading theory is that it is an adaptation 00:09:25.240 --> 00:09:28.120 to resist tensile stress. Okay, break that down 00:09:28.120 --> 00:09:30.820 for me. Tensile stress is what? Think about the 00:09:30.820 --> 00:09:33.960 physics. If you bite into a huge animal with 00:09:33.960 --> 00:09:35.940 the front of your jaws and then pull back to 00:09:35.940 --> 00:09:39.700 slice, that tearing motion puts immense stress 00:09:39.700 --> 00:09:41.659 on the tip of your jaw. It wants to pull it apart. 00:09:42.220 --> 00:09:46.120 Exactly. That chin acts as a structural reinforcement. 00:09:46.940 --> 00:09:49.179 It keeps the jaw from snapping under the tension 00:09:49.179 --> 00:09:51.679 of that pole. It's brilliant engineering. That's 00:09:51.679 --> 00:09:53.679 fascinating. And what about the rest of its face? 00:09:53.740 --> 00:09:56.720 I read the nasal bones were rugose. Yeah, rugose 00:09:56.720 --> 00:09:58.960 just means they were rough and wrinkly. And it 00:09:58.960 --> 00:10:01.279 had this sort of ridge -like crest in front of 00:10:01.279 --> 00:10:03.659 each eye. Not a horn like Allosaurus, but it 00:10:03.659 --> 00:10:06.220 was prominent. What was that for? Display. Probably 00:10:06.220 --> 00:10:08.740 display. In life, it might have supported some 00:10:08.740 --> 00:10:10.200 kind of keratin structure. We don't know for 00:10:10.200 --> 00:10:12.179 sure. But it would have given the animal this 00:10:12.179 --> 00:10:15.340 very distinct, rugged look. It wasn't a smooth 00:10:15.340 --> 00:10:17.340 -skinned lizard. Now, I have to ask about the 00:10:17.340 --> 00:10:19.980 brain. We always hear that dinosaurs weren't 00:10:19.980 --> 00:10:22.940 exactly rocket scientists. How does our giant 00:10:22.940 --> 00:10:26.700 southern friend stack up? Not great. They've 00:10:26.700 --> 00:10:29.519 done a latex endocast of the brain cavity. The 00:10:29.519 --> 00:10:32.340 total brain volume was about 275 milliliters. 00:10:32.399 --> 00:10:34.580 Which is that good? For an animal that size, 00:10:34.720 --> 00:10:37.320 no. It gives it what's called an encephalization 00:10:37.320 --> 00:10:41.320 quotient of about 1 .9. In plain English, it 00:10:41.320 --> 00:10:43.600 had a much smaller brain relative to its body 00:10:43.600 --> 00:10:45.919 size than a tyrannosaur did. So not the biggest 00:10:45.919 --> 00:10:48.980 thinker. Not the biggest thinker. The olfactory 00:10:48.980 --> 00:10:52.580 bulbs, the part for smell, were huge. So it was 00:10:52.580 --> 00:10:54.539 an instinct -driven predator that could follow 00:10:54.539 --> 00:10:56.879 a scent from miles away. But it wasn't solving 00:10:56.879 --> 00:11:00.039 puzzles. Okay, so big body, knife teeth, reinforced 00:11:00.039 --> 00:11:03.340 chin. Let's talk about the engine. Was it slow 00:11:03.340 --> 00:11:07.000 and sluggish like a reptile or more active? That 00:11:07.000 --> 00:11:09.570 connects to the whole warm blood debate. A study 00:11:09.570 --> 00:11:12.370 back in 1999 looked at oxygen isotopes in the 00:11:12.370 --> 00:11:14.990 bones. And they found it was homeothermic? Essentially, 00:11:15.210 --> 00:11:18.429 yes. It maintained a stable internal body temperature. 00:11:18.549 --> 00:11:20.789 Its metabolism was probably somewhere in between 00:11:20.789 --> 00:11:23.210 a modern reptile and a mammal. Which is pretty 00:11:23.210 --> 00:11:25.190 crucial, right? You don't get to be eight tons 00:11:25.190 --> 00:11:27.590 by growing slowly. You don't. You need a higher 00:11:27.590 --> 00:11:29.889 metabolism to fuel that kind of rapid growth. 00:11:30.129 --> 00:11:32.870 So it grew fast. Could it move fast? Can I outrun 00:11:32.870 --> 00:11:35.029 this thing in a Jeep? That is a subject of some 00:11:35.029 --> 00:11:39.129 very intense debate. In 2001, researchers Blanco 00:11:39.129 --> 00:11:42.429 and Mazzetta ran the numbers. They calculated 00:11:42.429 --> 00:11:45.809 a theoretical top speed of around 14 meters per 00:11:45.809 --> 00:11:48.750 second. Which is? About 50 kilometers per hour 00:11:48.750 --> 00:11:52.529 or 31 miles per hour. That is terrifyingly fast. 00:11:52.710 --> 00:11:55.070 That's faster than Usain Bolt for something the 00:11:55.070 --> 00:11:58.470 size of a bus. It is. But, and this is a very 00:11:58.470 --> 00:12:01.409 big but, they also pointed out the danger factor. 00:12:01.809 --> 00:12:05.019 When you're that heavy. stability becomes a nightmare. 00:12:05.200 --> 00:12:06.899 What do you mean the danger factor? Think about 00:12:06.899 --> 00:12:09.679 an eight -ton bipedal animal tripping while running 00:12:09.679 --> 00:12:12.779 30 miles per hour. The fall is fatal. Almost 00:12:12.779 --> 00:12:15.620 certainly. The impact forces would be catastrophic. 00:12:16.039 --> 00:12:18.460 Shattered ribs, punctured lungs, it's game over. 00:12:18.860 --> 00:12:20.559 So while it might have had the muscle power, 00:12:20.720 --> 00:12:23.059 it probably wasn't safe to do so. Some more recent 00:12:23.059 --> 00:12:25.940 studies have walked that back. Yes. A 2017 study 00:12:25.940 --> 00:12:28.639 suggested the skeletal loads on these giant theropods 00:12:28.639 --> 00:12:30.720 might have limited them to walking gates only. 00:12:31.159 --> 00:12:33.960 So no high -speed running. Just a very, very 00:12:33.960 --> 00:12:36.919 fast, ground -shaking power walk. Which, honestly, 00:12:37.019 --> 00:12:39.559 is almost scarier. This relentless stride that 00:12:39.559 --> 00:12:41.480 you can't get away from. It's the inevitability 00:12:41.480 --> 00:12:43.860 of it, exactly. So let's... Zoom out. We know 00:12:43.860 --> 00:12:47.299 what it looked like, how it moved, what world 00:12:47.299 --> 00:12:50.080 was it living in, who was on the menu. It was 00:12:50.080 --> 00:12:52.620 part of that family, the Carcharodontosauridae. 00:12:52.799 --> 00:12:55.620 Its relatives include Maposaurus, also from Argentina, 00:12:55.899 --> 00:12:58.399 and Carcharodontosaurus from Africa. Which tells 00:12:58.399 --> 00:13:05.600 us they were spread out before... After the Candelaris 00:13:05.600 --> 00:13:08.820 Formation, it was the undisputed king. And it 00:13:08.820 --> 00:13:11.100 wasn't hunting small game. It was sharing the 00:13:11.100 --> 00:13:14.519 landscape with titanosaurs. Massive long -necked 00:13:14.519 --> 00:13:17.860 sauropods like Andesaurus and Limasaurus. That 00:13:17.860 --> 00:13:20.539 seems like a tough meal. How does one predator 00:13:20.539 --> 00:13:22.539 take down an animal that might weigh five or 00:13:22.539 --> 00:13:24.759 six times what it does? And that leads to one 00:13:24.759 --> 00:13:26.779 of the most exciting theories about these animals, 00:13:26.899 --> 00:13:29.259 the pack -hunting hypothesis. Right, the idea 00:13:29.259 --> 00:13:31.690 that they work together like wolves. The evidence 00:13:31.690 --> 00:13:33.809 for this comes mainly from its cousin, Mappasaurus. 00:13:34.850 --> 00:13:37.269 Paleontologists found a bone bed with multiple 00:13:37.269 --> 00:13:39.970 Mappasaurus individuals of different ages all 00:13:39.970 --> 00:13:42.690 buried together. Which suggests they lived and 00:13:42.690 --> 00:13:45.750 maybe died together. Rudolfo Correa suggested 00:13:45.750 --> 00:13:48.210 it could point to group behavior. Because if 00:13:48.210 --> 00:13:50.509 you want to hunt a 40 -ton sauropod, you can't 00:13:50.509 --> 00:13:53.129 really do it alone. But if you have a gang... 00:13:53.129 --> 00:13:55.230 You can take down a giant. Now, we have to be 00:13:55.230 --> 00:13:58.129 careful. We don't have direct evidence of Giganotosaurus 00:13:58.129 --> 00:14:01.320 doing this. We haven't found a gigi -gang. bone 00:14:01.320 --> 00:14:04.440 bed but given the family ties and the prey it 00:14:04.440 --> 00:14:07.440 was eating it's a very plausible idea and it 00:14:07.440 --> 00:14:09.679 fits that jaw design we talked about if t -rex 00:14:09.679 --> 00:14:12.899 is a crusher it grabs and holds on but if giga 00:14:12.899 --> 00:14:16.139 is a slicer it suggests a war of attrition you 00:14:16.139 --> 00:14:19.519 run in inflict a massive, deep wound with those 00:14:19.519 --> 00:14:21.879 teeth, and then you retreat. You let the prey 00:14:21.879 --> 00:14:24.220 weaken from blood loss. The pack would surround 00:14:24.220 --> 00:14:26.419 it, keep it from escaping. And that's where the 00:14:26.419 --> 00:14:28.980 jaw mechanics are so interesting. The jaw joint 00:14:28.980 --> 00:14:31.220 was moved backward in the skull compared to other 00:14:31.220 --> 00:14:33.899 theropods. What does that do? It allows for faster 00:14:33.899 --> 00:14:36.899 jaw closure. It's built for speed. A quick snap 00:14:36.899 --> 00:14:39.460 and slice, not the slow, immense pressure of 00:14:39.460 --> 00:14:42.220 a tyrannosaur. You rush in, take a bite. back 00:14:42.220 --> 00:14:44.659 off, let your pack mates distract it, and come 00:14:44.659 --> 00:14:46.519 in again. It really is a completely different 00:14:46.519 --> 00:14:49.360 strategy. It is. And that's the big takeaway. 00:14:50.019 --> 00:14:52.720 Giganotosaurus isn't just T. rex, but from the 00:14:52.720 --> 00:14:56.059 south. It's a parallel lineage. While Tyrannosaurs 00:14:56.059 --> 00:14:58.620 were ruling the northern hemisphere with big 00:14:58.620 --> 00:15:02.000 brains and crushing jaws. The cartarodontosaurids 00:15:02.000 --> 00:15:04.919 were ruling the South with giant -sized slicing 00:15:04.919 --> 00:15:07.899 teeth and maybe even social hunting. It really 00:15:07.899 --> 00:15:10.620 does highlight how North America -centric our 00:15:10.620 --> 00:15:12.919 view of dinosaurs can be. We think of Hell Creek, 00:15:13.139 --> 00:15:16.159 T -Rex, Triceratops as the standard. But the 00:15:16.159 --> 00:15:18.519 Southern Hemisphere was producing these titans 00:15:18.519 --> 00:15:22.899 of equal, if not greater, It was a whole different 00:15:22.899 --> 00:15:25.460 world down there. An arms race on a massive scale. 00:15:25.659 --> 00:15:28.559 So we've unpacked the dune buggy discovery, the 00:15:28.559 --> 00:15:31.500 size wars, the slicing jaws. It's clear Giganotosaurus 00:15:31.500 --> 00:15:33.960 is an absolute A -lister. Without a doubt. An 00:15:33.960 --> 00:15:35.960 evolutionary masterpiece. But I want to leave 00:15:35.960 --> 00:15:37.639 our listeners with one final thought. We know 00:15:37.639 --> 00:15:40.620 they never met. Giganotosaurus and T -Rex. Separated 00:15:40.620 --> 00:15:42.559 by millions of years, thousands of miles of ocean. 00:15:42.720 --> 00:15:45.500 But just as a thought experiment, you put them 00:15:45.500 --> 00:15:47.639 in an arena. Ah, I know where this is going. 00:15:47.720 --> 00:15:50.570 The ultimate showdown. You have... The brute 00:15:50.570 --> 00:15:53.450 force crusher in one corner, T -Rex. And the 00:15:53.450 --> 00:15:55.950 surgical slicer in the other, Giganotosaurus. 00:15:56.610 --> 00:15:59.389 Who wins that fight? It's the classic debate, 00:15:59.549 --> 00:16:01.870 isn't it? The tank versus the swordsman. The 00:16:01.870 --> 00:16:04.190 T -Rex has the bite force. It's orders of magnitude 00:16:04.190 --> 00:16:06.830 stronger. If it gets a clean hold, it can end 00:16:06.830 --> 00:16:09.429 the fight in one chomp. Breaks the neck. Game 00:16:09.429 --> 00:16:12.210 over. But Giga has the reach. And it's probably 00:16:12.210 --> 00:16:14.830 longer. Maybe taller. It has the size advantage, 00:16:15.110 --> 00:16:17.330 the reach, and those teeth. It doesn't need to 00:16:17.330 --> 00:16:21.080 crush bone to inflict a fatal wound. If Euganodosaurus 00:16:21.080 --> 00:16:24.059 can use its agility and reach to land a massive 00:16:24.059 --> 00:16:26.840 slash to the neck or the leg first. The T -Rex 00:16:26.840 --> 00:16:29.240 bleeds out. It's a real toss -up. It all comes 00:16:29.240 --> 00:16:31.700 down to who lands that first clean hit. The knockout 00:16:31.700 --> 00:16:33.659 puncher versus the one that inflicts death by 00:16:33.659 --> 00:16:36.320 a thousand cuts. Well, one giant cut. One very, 00:16:36.379 --> 00:16:38.559 very deep cut. A toss -up that I think I would 00:16:38.559 --> 00:16:41.340 pay good money to see from a very, very safe 00:16:41.340 --> 00:16:43.720 distance. A very safe distance. Maybe from orbit. 00:16:44.259 --> 00:16:46.460 That's all for this deep dive into the Giant 00:16:46.460 --> 00:16:49.279 of the South. It's just incredible to think that 00:16:49.279 --> 00:16:51.799 this monster was stalking Gondwana. Thanks for 00:16:51.799 --> 00:16:53.940 listening and keep asking questions. You never 00:16:53.940 --> 00:16:55.980 know what you might find. Keep exploring.