1 00:00:00,454 --> 00:00:02,986 (dinosaur growling) 2 00:00:02,986 --> 00:00:05,986 (suspenseful music) 3 00:00:07,167 --> 00:00:09,584 (explosions) 4 00:00:11,300 --> 00:00:13,370 Dinosaurs embody the extreme 5 00:00:13,370 --> 00:00:17,283 in just about every possible way, their size, 6 00:00:18,130 --> 00:00:22,363 power, even the long-ago time in which they lived. 7 00:00:23,890 --> 00:00:26,780 It's no wonder, the more we learn about them, 8 00:00:26,780 --> 00:00:28,863 the more they continue to captivate us. 9 00:00:30,510 --> 00:00:35,220 I think that most people have an inherent fascination 10 00:00:35,220 --> 00:00:37,720 with animals and with the natural world, 11 00:00:37,720 --> 00:00:41,130 and dinosaurs are animals and the natural world 12 00:00:41,130 --> 00:00:43,333 on the grandest of scales. 13 00:00:45,720 --> 00:00:49,330 I think it's imagining living on our earth 14 00:00:49,330 --> 00:00:52,610 when earth was a completely different place filled 15 00:00:52,610 --> 00:00:55,943 with fantastical beasts that really ignites the imagination. 16 00:00:58,970 --> 00:01:01,790 They're like dragons or other mythological creatures 17 00:01:01,790 --> 00:01:04,380 but they were real, and that's part of the appeal. 18 00:01:04,380 --> 00:01:05,903 They were a real thing. 19 00:01:07,100 --> 00:01:09,290 They are awe inspiring. 20 00:01:09,290 --> 00:01:10,360 Just take T. rex. 21 00:01:10,360 --> 00:01:14,270 T. rex is a killer whale-sized animal walking around 22 00:01:14,270 --> 00:01:16,053 on these giant chicken legs. 23 00:01:17,280 --> 00:01:20,130 You can't really compare anything alive 24 00:01:20,130 --> 00:01:21,233 to a T. rex. 25 00:01:24,770 --> 00:01:27,970 We know when the reign of the T. rex ended. 26 00:01:27,970 --> 00:01:30,250 In the calamitous dinosaur extinction event 27 00:01:30,250 --> 00:01:33,880 65 million years ago, the result 28 00:01:33,880 --> 00:01:36,773 of a massive meteor crash in the Yucatan Peninsula. 29 00:01:39,000 --> 00:01:41,083 But how did its rule begin? 30 00:01:42,910 --> 00:01:44,840 Scientists have long sought to learn more 31 00:01:44,840 --> 00:01:46,850 about the early lineage of the king 32 00:01:46,850 --> 00:01:48,493 of the tyrant dinosaurs. 33 00:01:50,660 --> 00:01:54,123 Where and when can find the roots of its family tree? 34 00:01:56,290 --> 00:01:59,010 Now, new discoveries, as well as new analysis 35 00:01:59,010 --> 00:02:01,713 of old finds are beginning to fill in the timeline. 36 00:02:03,000 --> 00:02:06,090 Almost all we know about Tyrannosaur evolution comes 37 00:02:06,090 --> 00:02:08,510 from the final 15 million year of the Cretaceous 38 00:02:08,510 --> 00:02:10,860 leading up to the great T. rex. 39 00:02:10,860 --> 00:02:13,970 There's been this huge gap, 70 million years 40 00:02:13,970 --> 00:02:15,730 in the fossil record prior to that 41 00:02:15,730 --> 00:02:18,590 where we've had no fossil evidence 42 00:02:18,590 --> 00:02:20,470 of what types of Tyrannosaurs were living here, 43 00:02:20,470 --> 00:02:24,070 so we really had not pieced together the first three 44 00:02:24,070 --> 00:02:26,940 quarters of the story of tyrannosaur evolution 45 00:02:26,940 --> 00:02:28,040 here in North America. 46 00:02:29,830 --> 00:02:31,420 Lindsay Zanno is the head 47 00:02:31,420 --> 00:02:33,900 of paleontology at the North Carolina Museum 48 00:02:33,900 --> 00:02:35,023 of Natural History. 49 00:02:37,384 --> 00:02:40,580 For more than 10 years now, she's led research teams 50 00:02:40,580 --> 00:02:43,740 to a remote part of central Utah following a trail 51 00:02:43,740 --> 00:02:47,920 of small ancient Tyrannosaur teeth on the hunt 52 00:02:47,920 --> 00:02:48,883 for something more. 53 00:02:50,351 --> 00:02:51,640 (laughing) 54 00:02:51,640 --> 00:02:53,890 You guys, you're really helping. 55 00:02:53,890 --> 00:02:56,230 It's exciting to be part of the discovery. 56 00:02:56,230 --> 00:02:59,030 I think that's my favorite part of the scientific process 57 00:02:59,030 --> 00:03:02,210 and when we're out in the field, we come across things 58 00:03:02,210 --> 00:03:05,570 we never expected to find that can define our research 59 00:03:05,570 --> 00:03:06,513 for years to come. 60 00:03:08,460 --> 00:03:11,960 And that's just what happened in 2012. 61 00:03:11,960 --> 00:03:14,980 All right, so this is the upper leg bone. 62 00:03:14,980 --> 00:03:16,430 When they found the puzzle pieces 63 00:03:16,430 --> 00:03:19,850 to a new species of dinosaur, something very different 64 00:03:19,850 --> 00:03:21,740 than anything they'd seen before. 65 00:03:21,740 --> 00:03:23,150 The knee would have been here, and this is the 66 00:03:23,150 --> 00:03:23,983 lower leg bone. 67 00:03:23,983 --> 00:03:25,640 You can see where cut a section out 68 00:03:25,640 --> 00:03:27,480 to study those growth lines. 69 00:03:27,480 --> 00:03:28,313 It was amazing. 70 00:03:28,313 --> 00:03:30,390 The first part we saw sticking out of the hill 71 00:03:30,390 --> 00:03:33,530 was this bone and these pieces here are different colors 72 00:03:33,530 --> 00:03:36,950 because we actually found each one of these 73 00:03:36,950 --> 00:03:39,010 individual pieces trailing down the hill, 74 00:03:39,010 --> 00:03:42,010 collected them all, and then the preparation teams 75 00:03:42,010 --> 00:03:45,070 spent hundreds of hours piecing together each one 76 00:03:45,070 --> 00:03:47,130 of these little bits that we had collected 77 00:03:47,130 --> 00:03:48,430 from the side of the hill. 78 00:03:49,280 --> 00:03:51,460 After the painstaking excavation, 79 00:03:51,460 --> 00:03:54,544 cleaning and assembly work, the team concluded 80 00:03:54,544 --> 00:03:57,410 this leg belonged to a small, at most 81 00:03:57,410 --> 00:04:02,360 about 180-pound animal, similar to older tyrannosaur fossils 82 00:04:02,360 --> 00:04:05,630 found in Asia, hinting at a continental migration 83 00:04:05,630 --> 00:04:06,693 to North America. 84 00:04:08,150 --> 00:04:09,670 It's a very petite animal. 85 00:04:09,670 --> 00:04:11,410 It would have been about human size. 86 00:04:11,410 --> 00:04:12,940 So when this animal was standing next to you, 87 00:04:12,940 --> 00:04:14,130 he probably would have been able to look you 88 00:04:14,130 --> 00:04:15,343 right in the eyes. 89 00:04:18,130 --> 00:04:20,750 And the tissue between is pretty consistent. 90 00:04:20,750 --> 00:04:22,340 Zanno examined cross sections 91 00:04:22,340 --> 00:04:25,283 of the fossilized bone to determine the specimen's age, 92 00:04:26,270 --> 00:04:28,193 about seven at the time of death. 93 00:04:29,070 --> 00:04:31,920 Just like counting the growth rings you'd find in a tree. 94 00:04:32,930 --> 00:04:35,200 Its growth seemed to be slowing, so it was actually 95 00:04:35,200 --> 00:04:38,300 approaching its adult body size when it died. 96 00:04:38,300 --> 00:04:41,780 So this actually wasn't just a young Tyrannosaur 97 00:04:41,780 --> 00:04:42,613 of a big species. 98 00:04:42,613 --> 00:04:44,823 This was actually a tiny Tyrannosaur. 99 00:04:46,310 --> 00:04:49,160 Seven years old when it died perhaps. 100 00:04:49,160 --> 00:04:52,210 But a fossil that's now 96 million years old 101 00:04:52,210 --> 00:04:55,130 and begins to fill in a 70-million year gap 102 00:04:55,130 --> 00:04:58,023 in the fossil record of North American Tyrannosaurs. 103 00:04:58,960 --> 00:05:02,053 Zanno published her findings in February, 2019. 104 00:05:03,370 --> 00:05:05,410 I chose the name Moros intrepidus 105 00:05:05,410 --> 00:05:09,288 just to represent that this is really the origin story 106 00:05:09,288 --> 00:05:12,050 of the T. rex lineage here in North America. 107 00:05:12,050 --> 00:05:15,330 Moros means the harbinger of doom, and T. rex 108 00:05:15,330 --> 00:05:19,043 is definitely the doom bringer, so it all made sense. 109 00:05:20,870 --> 00:05:23,920 On the dinosaur timeline, small Moros lands 110 00:05:23,920 --> 00:05:27,650 in the mid Cretaceous period, while the enormous T. rex 111 00:05:27,650 --> 00:05:29,573 lived during the late Cretaceous. 112 00:05:31,150 --> 00:05:34,340 With 30 million years in between, what suggests 113 00:05:34,340 --> 00:05:35,673 they're closely related? 114 00:05:36,890 --> 00:05:39,210 An evolutionary adaption not present 115 00:05:39,210 --> 00:05:43,523 in those early Asian relatives, a specialized foot. 116 00:05:44,630 --> 00:05:46,650 One of the things that makes Tyrannosaurs so special 117 00:05:46,650 --> 00:05:48,873 is they have a very unique foot. 118 00:05:50,030 --> 00:05:52,840 It's very pinched and it's designed for running 119 00:05:52,840 --> 00:05:54,590 and also being very agile. 120 00:05:54,590 --> 00:05:56,780 So these were incredible hunters that were able 121 00:05:56,780 --> 00:05:58,013 to chase down prey. 122 00:06:00,090 --> 00:06:03,190 Moros is the earliest example of those special 123 00:06:03,190 --> 00:06:05,400 tyrannosaur adaptations that we found 124 00:06:05,400 --> 00:06:06,450 in the fossil record. 125 00:06:09,420 --> 00:06:13,680 So somewhat like a T. rex is small, fast tyrant dinosaur 126 00:06:13,680 --> 00:06:17,280 grown huge, not a big, fat tyrant dinosaur 127 00:06:17,280 --> 00:06:19,300 that then was evolving a few new traits 128 00:06:19,300 --> 00:06:20,800 to make it go a little faster. 129 00:06:21,700 --> 00:06:24,080 Professor Thomas Holtz is a paleontologist 130 00:06:24,080 --> 00:06:27,563 at the University of Maryland specializing in Tyrannosaurs. 131 00:06:28,480 --> 00:06:31,253 He was part of the peer review for Zanno's paper. 132 00:06:32,380 --> 00:06:36,240 And with that adaptation, when they got the chance, 133 00:06:36,240 --> 00:06:38,890 Tyrannosaurs could become the fastest-moving 134 00:06:38,890 --> 00:06:40,960 large predators of all time. 135 00:06:40,960 --> 00:06:43,520 But they acquired it when they were still little guys, 136 00:06:43,520 --> 00:06:45,630 and they were probably using that fast-running foot 137 00:06:45,630 --> 00:06:48,080 as much to get away from being eaten 138 00:06:48,080 --> 00:06:49,683 as to chase things to eat. 139 00:06:50,610 --> 00:06:52,450 That's because during its time, 140 00:06:52,450 --> 00:06:55,093 small Moros was not the apex predator. 141 00:06:58,244 --> 00:06:59,320 (dinosaurs roaring) 142 00:06:59,320 --> 00:07:02,463 This lush world belonged to the much larger Allosaurus. 143 00:07:03,920 --> 00:07:07,100 Somehow though, the Allosaurus disappear, 144 00:07:07,100 --> 00:07:09,530 perhaps victims of a changing environment 145 00:07:09,530 --> 00:07:12,265 leaving Moros and its Tyrannosaur descendants 146 00:07:12,265 --> 00:07:13,493 a void to fill. 147 00:07:16,000 --> 00:07:18,280 And so likely as soon as their major competitors 148 00:07:18,280 --> 00:07:19,900 were out of the scene, they were able 149 00:07:19,900 --> 00:07:23,840 to seize that opportunity, increase in size really quickly 150 00:07:23,840 --> 00:07:25,610 and take over as the top predators 151 00:07:25,610 --> 00:07:27,093 of these new ecosystems. 152 00:07:29,520 --> 00:07:30,960 But what drove the Tyrannosaur's 153 00:07:30,960 --> 00:07:33,193 exponential growth remains a mystery. 154 00:07:35,080 --> 00:07:38,146 From Moros weighing in at 180 pounds, 155 00:07:38,146 --> 00:07:41,950 to the T. rex known as Scotty, now considered 156 00:07:41,950 --> 00:07:45,500 the largest T. rex ever discovered, tipping the scales 157 00:07:45,500 --> 00:07:48,513 at more than 19,500 pounds. 158 00:07:50,080 --> 00:07:54,150 Why Tyrannosaurs evolved to to be so big is still 159 00:07:54,150 --> 00:07:56,820 a huge paleontological question. 160 00:07:56,820 --> 00:07:59,070 Tyrannosaurus rex pushes the boundaries 161 00:07:59,070 --> 00:08:01,120 of any big carnivores that we know about. 162 00:08:03,180 --> 00:08:06,030 Scott Persons investigates those boundaries. 163 00:08:06,940 --> 00:08:09,900 A research fellow at the University of Alberta, 164 00:08:09,900 --> 00:08:12,310 he's also lead author on a new study 165 00:08:12,310 --> 00:08:16,740 about the dinosaur, Scotty, fossils found in the Badlands 166 00:08:16,740 --> 00:08:19,183 of Saskatchewan in 1991. 167 00:08:23,400 --> 00:08:26,480 But its skeletal assembly was only just installed 168 00:08:26,480 --> 00:08:31,413 for display at the Royal Saskatchewan Museum in May, 2019. 169 00:08:34,910 --> 00:08:38,040 Scotty earned its name because shortly after 170 00:08:38,040 --> 00:08:42,270 it was discovered, the field crew got really, really excited 171 00:08:42,270 --> 00:08:45,450 and they wanted that evening to raise a glass 172 00:08:45,450 --> 00:08:48,663 to Tyrannosaurus rex, to toast the tyrant king. 173 00:08:50,550 --> 00:08:53,470 And the only bottle that they had on hand 174 00:08:53,470 --> 00:08:57,433 that seemed appropriate was a very old bottle of scotch. 175 00:09:05,070 --> 00:09:07,400 I became involved in researching Scotty 176 00:09:07,400 --> 00:09:09,070 only about two years ago. 177 00:09:09,070 --> 00:09:12,020 That was after the fossils were fully excavated 178 00:09:12,020 --> 00:09:15,313 and fully prepared, so they were ready for scientific study. 179 00:09:17,290 --> 00:09:19,630 The team at the Royal Saskatchewan Museum 180 00:09:19,630 --> 00:09:23,373 used laser scanners to create 3D images of the bones. 181 00:09:25,600 --> 00:09:28,660 Now almost 30 years after the initial discovery, 182 00:09:28,660 --> 00:09:31,210 Persons's new analysis revealed Scotty 183 00:09:31,210 --> 00:09:36,210 to be the T. rex ever found, dethroning Sue 184 00:09:36,450 --> 00:09:38,333 from the Chicago Field Museum. 185 00:09:40,550 --> 00:09:42,790 We say Scotty is the biggest in terms 186 00:09:42,790 --> 00:09:44,610 of its absolute body mass. 187 00:09:44,610 --> 00:09:47,400 So those skeletal measurements that indicate 188 00:09:47,400 --> 00:09:49,470 just how much the animal would have weighted 189 00:09:49,470 --> 00:09:52,490 suggest that Scotty is the most massive. 190 00:09:52,490 --> 00:09:55,410 And when you look at things like the girth 191 00:09:55,410 --> 00:09:58,090 of the femur, so the femoral circumference, 192 00:09:58,090 --> 00:10:01,480 when you look at the length of the lower jaw, 193 00:10:01,480 --> 00:10:06,480 when you look at even the thickness of the shoulder, 194 00:10:06,640 --> 00:10:08,403 Scotty comes out ahead. 195 00:10:09,620 --> 00:10:11,530 Thomas Holtz also peer reviewed 196 00:10:11,530 --> 00:10:12,653 Persons's paper. 197 00:10:14,140 --> 00:10:17,263 And honest to goodness, we can't say that Scotty, 198 00:10:17,263 --> 00:10:21,330 on the lean season, when there's not much food, 199 00:10:21,330 --> 00:10:24,870 and Sue in the season when there's a lot of food, 200 00:10:24,870 --> 00:10:27,420 Sue may have been heavier some times of the year, 201 00:10:27,420 --> 00:10:29,910 and Scotty heavier some of the other times of the year. 202 00:10:29,910 --> 00:10:33,550 But overall the evidence is, on average, Scotty 203 00:10:33,550 --> 00:10:35,510 is a larger individual than Sue. 204 00:10:35,510 --> 00:10:38,060 And Sue is already a really, really, really 205 00:10:38,060 --> 00:10:39,650 massive individual. 206 00:10:39,650 --> 00:10:42,710 So Scotty is the rex of rex's. 207 00:10:42,710 --> 00:10:45,303 It's the king of the Tyrannosaurs. 208 00:10:46,221 --> 00:10:48,300 An estimated 30 years old 209 00:10:48,300 --> 00:10:51,700 at the time of death, Scotty is also the oldest 210 00:10:51,700 --> 00:10:52,823 T. rex ever found. 211 00:10:56,950 --> 00:11:00,130 In a world where Scotty and the other big animals 212 00:11:00,130 --> 00:11:03,600 are around, are only living to about 30 years old, 213 00:11:03,600 --> 00:11:06,030 it's telling us there's a lot of turnover going. 214 00:11:06,030 --> 00:11:08,490 There's a lot of individuals changing over 215 00:11:08,490 --> 00:11:09,563 in the population. 216 00:11:10,700 --> 00:11:13,643 As I like to say, in the Mesozoic, life was cheap. 217 00:11:14,840 --> 00:11:17,860 Scotty shows evidence of a busted 218 00:11:17,860 --> 00:11:19,800 and then infected jaw. 219 00:11:19,800 --> 00:11:22,870 Its got several broken and healed ribs. 220 00:11:22,870 --> 00:11:26,840 Its also got a number of vertebrae in the tail 221 00:11:26,840 --> 00:11:30,680 that shows signs of very strong compression 222 00:11:30,680 --> 00:11:32,940 and that may be indicative of a place 223 00:11:32,940 --> 00:11:37,023 where Scotty actually got bit by another Tyrannosaurus rex. 224 00:11:39,150 --> 00:11:43,000 So Scotty's bones tell us a lot about its very long 225 00:11:43,000 --> 00:11:45,110 and very violent life. 226 00:11:45,110 --> 00:11:48,230 Nothing however is written in stone. 227 00:11:48,230 --> 00:11:50,750 The chances that we've actually uncovered 228 00:11:50,750 --> 00:11:53,985 the very biggest of all time Tyrannosaurs rex 229 00:11:53,985 --> 00:11:56,910 is infinitesimally small. 230 00:11:56,910 --> 00:11:59,390 So it's very unlikely that Scotty is going 231 00:11:59,390 --> 00:12:03,970 to remain the king of the Tyrannosaurs forever. 232 00:12:03,970 --> 00:12:06,000 Tyrannosaurus rex is an animal that was around 233 00:12:06,000 --> 00:12:07,380 for millions of years. 234 00:12:07,380 --> 00:12:11,100 It can be found from across western North America. 235 00:12:11,100 --> 00:12:13,410 I find it impossible to believe that 236 00:12:13,410 --> 00:12:17,210 in all that time and space, we have been lucky enough 237 00:12:17,210 --> 00:12:20,780 to discover the single largest individual that ever was. 238 00:12:20,780 --> 00:12:24,220 There are undoubtedly bigger Tyrannosaur skeletons out there 239 00:12:24,220 --> 00:12:25,373 waiting to be found. 240 00:12:26,560 --> 00:12:29,490 And maybe smaller ones too, descendants 241 00:12:29,490 --> 00:12:31,840 of Moros Intrepidus that can continue 242 00:12:31,840 --> 00:12:33,623 to fill in gaps in our knowledge. 243 00:12:35,540 --> 00:12:39,100 We need to find more Tyrannosaurs that lived 244 00:12:39,100 --> 00:12:42,020 slightly after Moros to really understand how quickly 245 00:12:42,020 --> 00:12:44,310 they were able to grow and assume those 246 00:12:44,310 --> 00:12:46,360 top predator roles here in North America. 247 00:12:47,890 --> 00:12:50,270 In the span of a month, the world learned 248 00:12:50,270 --> 00:12:53,070 new information about two fantastic creatures 249 00:12:53,070 --> 00:12:55,993 that roamed the earth tens of millions of years ago. 250 00:12:57,650 --> 00:12:59,303 What's next on the horizon? 251 00:13:00,380 --> 00:13:02,423 How will the future shape the past? 252 00:13:03,900 --> 00:13:07,070 More species of dinosaurs are being found now 253 00:13:07,070 --> 00:13:10,290 than basically any other point in human history. 254 00:13:10,290 --> 00:13:13,260 And so we right now are in the golden age 255 00:13:13,260 --> 00:13:15,263 of dinosaur discoveries. 256 00:13:16,230 --> 00:13:19,560 There are 50 to 70 new dinosaur species named 257 00:13:19,560 --> 00:13:21,010 every single year. 258 00:13:21,010 --> 00:13:23,780 It's incredible the pace of research 259 00:13:23,780 --> 00:13:25,910 and also we're at a stage where we're able 260 00:13:25,910 --> 00:13:28,600 to apply new techniques to the study of dinosaurs 261 00:13:28,600 --> 00:13:31,970 that allow us to get new information from bones 262 00:13:31,970 --> 00:13:34,870 that we've had in museum collections for a very long time. 263 00:13:37,400 --> 00:13:39,610 We're filling in gaps in the history 264 00:13:39,610 --> 00:13:43,028 of well-known dinosaurs and we're finding specimens 265 00:13:43,028 --> 00:13:46,530 of even the most famous dinosaur that are telling us 266 00:13:46,530 --> 00:13:49,860 new things about their biology, about their growth, 267 00:13:49,860 --> 00:13:53,010 about their size, that we didn't know before. 268 00:13:53,010 --> 00:13:57,961 We are no where at the end of learning about dinosaurs 269 00:13:57,961 --> 00:14:02,370 and in generations to come, we will be knowing things 270 00:14:02,370 --> 00:14:04,580 about the lives of these ancient creatures 271 00:14:04,580 --> 00:14:06,973 that would probably blow our minds today. 272 00:14:08,163 --> 00:14:10,663 (light music)