1 00:00:01,000 --> 00:00:03,000 KIRK JOHNSON: 2 00:00:01,000 --> 00:00:04,999 the land that we love. 3 00:00:03,001 --> 00:00:05,000 North America, 4 00:00:05,000 --> 00:00:06,000 It looks pretty familiar, 5 00:00:06,001 --> 00:00:07,001 don'T you think? 6 00:00:09,000 --> 00:00:10,000 (explosion) 7 00:00:12,000 --> 00:00:13,000 Well, think again! 8 00:00:19,000 --> 00:00:21,000 The ground we walk on 9 00:00:21,001 --> 00:00:22,999 is full of surprises 10 00:00:23,000 --> 00:00:25,999 if you know where to look. 11 00:00:26,000 --> 00:00:27,000 - As a geologist, - the Grand Canyon is perhaps 12 00:00:27,001 --> 00:00:28,000 The best place in the world. 13 00:00:28,001 --> 00:00:29,500 Every single one of these layers 14 00:00:29,501 --> 00:00:30,999 tells its own story 15 00:00:31,000 --> 00:00:32,000 about what North America 16 00:00:32,001 --> 00:00:33,000 was like 17 00:00:33,001 --> 00:00:35,999 when that layer was deposited. 18 00:00:36,000 --> 00:00:38,000 - So are you ready - for a little time traveling? 19 00:00:38,003 --> 00:00:39,999 I'M Kirk Johnson, the director 20 00:00:40,000 --> 00:00:42,500 of the Smithsonian National. 21 00:00:42,501 --> 00:00:44,999 Museum of Natural History. 22 00:00:45,000 --> 00:00:47,000 And I'M taking off on 23 00:00:47,001 --> 00:00:48,999 the field trip of a lifetime... 24 00:00:49,000 --> 00:00:50,000 Wow, look at that rock 25 00:00:50,001 --> 00:00:51,000 right there. 26 00:00:51,001 --> 00:00:52,999 That is crazy! 27 00:00:53,000 --> 00:00:55,000 to unlock the secrets of our 28 00:00:55,001 --> 00:00:56,999 continent'S incredible past. 29 00:00:57,000 --> 00:00:59,500 In this episode, we going 30 00:00:59,501 --> 00:01:01,999 to jump back millions of years 31 00:01:02,000 --> 00:01:03,999 to a North America that'S full 32 00:01:04,000 --> 00:01:05,500 of all kinds 33 00:01:05,501 --> 00:01:06,999 of unusual creatures... 34 00:01:07,000 --> 00:01:08,999 Yikes! 35 00:01:09,000 --> 00:01:10,500 turning up in the most 36 00:01:10,501 --> 00:01:12,000 unexpected places. 37 00:01:13,000 --> 00:01:14,999 A 14-foot-long fish in Kansas? 38 00:01:15,000 --> 00:01:17,000 - MAN: - That'S what I'M telling you! 39 00:01:19,000 --> 00:01:21,500 JOHNSON: 40 00:01:19,000 --> 00:01:24,000 the Midwest was underwater. 41 00:01:21,501 --> 00:01:24,000 It'S a time when much of 42 00:01:29,000 --> 00:01:30,500 I'M on the hunt for clues 43 00:01:30,501 --> 00:01:31,999 to the amazing connection 44 00:01:32,000 --> 00:01:34,000 between our land and everything 45 00:01:34,001 --> 00:01:36,000 that'S ever lived here. 46 00:01:41,000 --> 00:01:42,000 From the rise of early life... 47 00:01:42,001 --> 00:01:43,500 NOAH PLANAVSKY: 48 00:01:43,501 --> 00:01:44,999 What I'M holding in my hands 49 00:01:45,000 --> 00:01:46,000 - is a fossil that'S - two billion years old. 50 00:01:46,003 --> 00:01:47,999 Wow. 51 00:01:48,000 --> 00:01:49,500 JOHNSON: 52 00:01:48,000 --> 00:01:50,999 biggest, baddest beasts 53 00:01:49,501 --> 00:01:51,000 To the destruction of the 54 00:01:51,000 --> 00:01:52,000 of all time. 55 00:01:52,001 --> 00:01:53,999 (explosion) 56 00:01:54,000 --> 00:01:56,000 It doesn'T look like much, 57 00:01:56,001 --> 00:01:58,000 but this layer is Armageddon. 58 00:02:04,000 --> 00:02:06,000 "Making North America: Life," 59 00:02:06,001 --> 00:02:08,000 right now on NOVA. 60 00:02:25,000 --> 00:02:26,500 Major funding for NOVA 61 00:02:26,501 --> 00:02:28,000 is provided by the following: 62 00:02:33,000 --> 00:02:35,000 Shouldn'T what makes 63 00:02:33,000 --> 00:02:36,999 with gleaming cities, 64 00:02:35,001 --> 00:02:37,000 each of us uniqueilled 65 00:02:37,000 --> 00:02:41,999 almost half a billion people, 66 00:02:42,000 --> 00:02:44,000 and still, some spectacular 67 00:02:44,001 --> 00:02:46,000 wildlife. 68 00:02:58,000 --> 00:03:00,999 But if we could rewind the clock 69 00:03:01,000 --> 00:03:02,500 and travel back in time 70 00:03:02,501 --> 00:03:03,999 millions of years, 71 00:03:04,000 --> 00:03:05,500 life on our continent gets 72 00:03:05,501 --> 00:03:06,999 a whole lot wilder. 73 00:03:07,000 --> 00:03:08,000 Yikes! 74 00:03:08,001 --> 00:03:10,000 That makes a grizzly bear 75 00:03:10,001 --> 00:03:12,000 look like nothing. 76 00:03:13,000 --> 00:03:14,000 This land is filled 77 00:03:14,001 --> 00:03:15,000 with the bones 78 00:03:15,001 --> 00:03:17,000 of some mind-blowing ancient 79 00:03:17,001 --> 00:03:18,999 creatures that once roamed 80 00:03:19,000 --> 00:03:21,999 and swam across a continent 81 00:03:22,000 --> 00:03:23,500 that was completely different 82 00:03:23,501 --> 00:03:24,999 from the familiar place 83 00:03:25,000 --> 00:03:28,999 we call home today. 84 00:03:29,000 --> 00:03:30,500 When you dig deep 85 00:03:30,501 --> 00:03:31,999 and follow the clues, 86 00:03:32,000 --> 00:03:33,500 you uncover 87 00:03:33,501 --> 00:03:35,000 an incredible fact... 88 00:03:37,000 --> 00:03:38,500 That powerful forces 89 00:03:38,501 --> 00:03:39,999 in the ground beneath our feet 90 00:03:40,000 --> 00:03:41,500 and the rocks all around us 91 00:03:41,501 --> 00:03:42,999 have shaped every plant 92 00:03:43,000 --> 00:03:44,000 and animal that'S 93 00:03:44,001 --> 00:03:45,001 ever lived here. 94 00:03:49,000 --> 00:03:51,500 You just have to look to follow 95 00:03:51,501 --> 00:03:53,999 the twists and turns, 96 00:03:54,000 --> 00:03:58,999 the ups and the downs... 97 00:03:59,000 --> 00:04:00,500 of North America'S 98 00:04:00,501 --> 00:04:02,000 incredible life story. 99 00:04:28,000 --> 00:04:30,000 In an empty corner of Utah 100 00:04:30,001 --> 00:04:32,000 lies a very special landscape. 101 00:04:47,000 --> 00:04:49,500 I'M flying over a remote region 102 00:04:49,501 --> 00:04:52,000 called the Kaiparowits Plateau. 103 00:05:04,000 --> 00:05:06,000 - I love this place because its - rocks contain a record 104 00:05:06,003 --> 00:05:07,500 Of one of the most important 105 00:05:07,501 --> 00:05:08,999 chapters 106 00:05:09,000 --> 00:05:10,500 in the history of life 107 00:05:10,501 --> 00:05:12,000 in North America. 108 00:05:24,000 --> 00:05:25,500 My guide for the day is 109 00:05:25,501 --> 00:05:26,999 paleontologist Joe Sertich, 110 00:05:27,000 --> 00:05:29,500 an old friend from the Denver. 111 00:05:29,501 --> 00:05:31,999 Museum of Nature and Science. 112 00:05:32,000 --> 00:05:33,000 SERTICH: 113 00:05:32,000 --> 00:05:33,999 a paleontologist, huh? 114 00:05:33,001 --> 00:05:34,000 Pretty good place to be 115 00:05:34,000 --> 00:05:35,000 JOHNSON: 116 00:05:35,001 --> 00:05:36,001 Oh yeah, this is awesome. 117 00:05:41,000 --> 00:05:43,000 JOHNSON: 118 00:05:41,000 --> 00:05:44,999 amazing for paleontologists 119 00:05:43,001 --> 00:05:45,000 What makes the Kaiparowits so 120 00:05:45,000 --> 00:05:47,000 is that it'S jam-packed full 121 00:05:47,001 --> 00:05:49,000 of dinosaur fossils. 122 00:05:53,000 --> 00:05:54,999 They'Re sticking out everywhere. 123 00:05:55,000 --> 00:05:56,999 Hey, look at that! 124 00:05:57,000 --> 00:05:58,500 All sorts of chunks of little 125 00:05:58,501 --> 00:05:59,999 bone here, it looks like. 126 00:06:00,000 --> 00:06:02,000 JOHNSON: 127 00:06:00,000 --> 00:06:03,999 my favorite little trick 128 00:06:02,001 --> 00:06:04,000 This is a great place for using 129 00:06:04,000 --> 00:06:05,000 for testing fossils. 130 00:06:05,001 --> 00:06:07,000 Uh-uh, it sticks on the end 131 00:06:07,001 --> 00:06:08,999 of the tongue. 132 00:06:09,000 --> 00:06:10,000 It actually sticks really hard. 133 00:06:10,001 --> 00:06:11,500 The little pores in the bone 134 00:06:11,501 --> 00:06:12,999 will try and pull the water 135 00:06:13,000 --> 00:06:14,000 out of your tongue, 136 00:06:14,000 --> 00:06:15,000 and a real piece of fossil bone 137 00:06:15,001 --> 00:06:17,000 - will stick really hard - to the tip of your tongue. 138 00:06:21,000 --> 00:06:23,000 - But Joe hasn'T brought me - all the way out here 139 00:06:23,003 --> 00:06:25,000 To suck on a few broken bones. 140 00:06:28,000 --> 00:06:30,500 He'S got something much cooler 141 00:06:30,501 --> 00:06:32,999 to show me, 142 00:06:33,000 --> 00:06:35,500 the cast of a skull belonging 143 00:06:35,501 --> 00:06:37,999 to a new species of dinosaur 144 00:06:38,000 --> 00:06:39,500 discovered right here 145 00:06:39,501 --> 00:06:40,999 that Joe helped identify. 146 00:06:41,000 --> 00:06:42,000 - SERTICH: - I think you'Re going 147 00:06:41,000 --> 00:06:42,000 To like this. 148 00:06:42,001 --> 00:06:43,999 Whoa, look at that. 149 00:06:44,000 --> 00:06:45,000 Yeah. 150 00:06:45,001 --> 00:06:46,999 This is the lower jaw. 151 00:06:47,000 --> 00:06:49,000 Well, there'S no doubt 152 00:06:49,001 --> 00:06:50,999 that guy'S a meat-eater. 153 00:06:51,000 --> 00:06:52,500 Look at that, little 154 00:06:52,501 --> 00:06:53,999 steak knives in his face. 155 00:06:54,000 --> 00:06:55,000 Exactly. 156 00:06:55,000 --> 00:06:56,000 Yikes. 157 00:06:56,001 --> 00:06:58,000 That makes a grizzly bear 158 00:06:58,001 --> 00:07:00,000 look like nothing. 159 00:07:03,000 --> 00:07:04,000 SERTICH: 160 00:07:03,000 --> 00:07:04,999 called Lythronax. 161 00:07:04,001 --> 00:07:05,000 This is a dinosaur 162 00:07:05,000 --> 00:07:06,000 JOHNSON: - Lythronax? 163 00:07:06,001 --> 00:07:07,000 - Lythronax is - a pretty cool name. 164 00:07:07,003 --> 00:07:09,000 - It actually means - the king of gore. 165 00:07:09,001 --> 00:07:10,000 The king of gore? 166 00:07:10,000 --> 00:07:11,000 Yeah. 167 00:07:11,001 --> 00:07:12,500 JOHNSON: 168 00:07:12,501 --> 00:07:13,999 Who came up with that name? 169 00:07:14,000 --> 00:07:15,000 - I did. - You did. 170 00:07:15,003 --> 00:07:16,999 (both laughing) 171 00:07:17,000 --> 00:07:18,000 - That'S one of the things - about finding dinosaurs, 172 00:07:18,001 --> 00:07:19,000 You get to name them. 173 00:07:19,001 --> 00:07:21,000 - You get to come up - with the name... exactly. 174 00:07:23,000 --> 00:07:25,000 JOHNSON: 175 00:07:23,000 --> 00:07:26,999 about the King of Gore 176 00:07:25,001 --> 00:07:27,000 The really exciting thing 177 00:07:27,000 --> 00:07:28,500 is that when you put flesh on 178 00:07:28,501 --> 00:07:30,000 the bones that Joe found... 179 00:07:33,000 --> 00:07:34,999 Lythronax looks a lot 180 00:07:35,000 --> 00:07:37,500 like the much more famous 181 00:07:37,501 --> 00:07:39,999 and fearsome Tyrannosaurus rex. 182 00:07:40,000 --> 00:07:41,500 But it'S ten million years 183 00:07:41,501 --> 00:07:42,999 older. 184 00:07:43,000 --> 00:07:44,500 Maybe he was T. Rex'S 185 00:07:44,501 --> 00:07:46,000 great-great-great-granddaddy. 186 00:07:54,000 --> 00:07:56,000 80 million years ago, 187 00:07:56,001 --> 00:07:57,999 all of North America, 188 00:07:58,000 --> 00:07:59,999 not just the Kairparowits, 189 00:08:00,000 --> 00:08:01,500 was home to creatures 190 00:08:01,501 --> 00:08:03,000 like Lythronax. 191 00:08:08,000 --> 00:08:09,500 And for the next 192 00:08:09,501 --> 00:08:10,999 14 million years, 193 00:08:11,000 --> 00:08:13,000 our continent was like 194 00:08:13,001 --> 00:08:14,999 a dinosaur movie set 195 00:08:15,000 --> 00:08:16,500 with a cast list featuring some 196 00:08:16,501 --> 00:08:17,999 of the biggest superstars, 197 00:08:18,000 --> 00:08:22,999 like T. Rex, the hadrosaurs, 198 00:08:23,000 --> 00:08:25,500 and my favorite dinosaur, 199 00:08:25,501 --> 00:08:28,000 triceratops. 200 00:08:30,000 --> 00:08:31,500 We know this because we find 201 00:08:31,501 --> 00:08:32,999 their fossils 202 00:08:33,000 --> 00:08:34,999 all over the place. 203 00:08:35,000 --> 00:08:37,000 In fact, of all the dinosaur 204 00:08:37,001 --> 00:08:38,999 species discovered worldwide, 205 00:08:39,000 --> 00:08:40,500 fossils of more than a quarter 206 00:08:40,501 --> 00:08:41,999 of them have been found here 207 00:08:42,000 --> 00:08:43,999 in North America. 208 00:08:44,000 --> 00:08:46,000 So the big question 209 00:08:46,001 --> 00:08:48,000 for me is, why? 210 00:08:51,000 --> 00:08:53,999 What was it about North America 211 00:08:54,000 --> 00:08:56,000 that made it such 212 00:08:56,001 --> 00:08:57,999 a dinosaur factory? 213 00:08:58,000 --> 00:09:00,000 What was the continent like back 214 00:09:00,001 --> 00:09:01,999 then that it could produce 215 00:09:02,000 --> 00:09:04,000 such a diverse cast 216 00:09:04,001 --> 00:09:05,999 of dino characters? 217 00:09:06,000 --> 00:09:08,000 Well, before we can unravel this 218 00:09:08,001 --> 00:09:09,999 mystery, we need to understand 219 00:09:10,000 --> 00:09:12,000 the intimate connection between 220 00:09:12,001 --> 00:09:13,999 life and the land. 221 00:09:14,000 --> 00:09:16,000 It'S a process that'S been going 222 00:09:16,001 --> 00:09:17,999 on since life first emerged 223 00:09:18,000 --> 00:09:20,500 more than three-and-a-half 224 00:09:20,501 --> 00:09:22,999 billion years ago, 225 00:09:23,000 --> 00:09:25,000 long before the dinosaurs roamed 226 00:09:25,001 --> 00:09:26,999 the land, 227 00:09:27,000 --> 00:09:29,500 in a time before North America 228 00:09:29,501 --> 00:09:31,999 even existed 229 00:09:32,000 --> 00:09:34,000 and the earth was covered 230 00:09:34,001 --> 00:09:36,000 almost entirely in ocean. 231 00:09:37,000 --> 00:09:38,500 There'S some intriguing evidence 232 00:09:38,501 --> 00:09:39,999 for this link 233 00:09:40,000 --> 00:09:42,500 in an unexpected corner 234 00:09:42,501 --> 00:09:44,999 of the North American plate: 235 00:09:45,000 --> 00:09:47,000 The Bahamas. 236 00:09:54,000 --> 00:09:56,000 I'Ve come here to see a rare 237 00:09:56,001 --> 00:09:57,999 living fossil, 238 00:09:58,000 --> 00:09:59,000 one that helped change 239 00:09:59,001 --> 00:10:00,001 the earth itself. 240 00:10:02,000 --> 00:10:04,000 Without it, life as we know it 241 00:10:04,001 --> 00:10:06,000 might not even exist. 242 00:10:08,000 --> 00:10:11,500 My guides are marine scientists. 243 00:10:11,501 --> 00:10:14,999 Noah Planavsky and Pamela Reid. 244 00:10:15,000 --> 00:10:16,500 So what did you think when 245 00:10:16,501 --> 00:10:17,999 you first saw these things? 246 00:10:18,000 --> 00:10:20,000 - You feel like you'Ve stepped - back in time 247 00:10:20,001 --> 00:10:21,000 To early earth. 248 00:10:21,001 --> 00:10:23,000 - It'S another world. - You'Ll see. 249 00:10:23,003 --> 00:10:24,500 I'Ve been waiting my whole life 250 00:10:24,501 --> 00:10:25,999 to see these things. 251 00:10:26,000 --> 00:10:28,500 JOHNSON: 252 00:10:26,000 --> 00:10:30,999 got to dive down about 20 feet, 253 00:10:28,501 --> 00:10:31,000 But to see anything, first we'Ve 254 00:10:31,000 --> 00:10:32,000 where we'Ll have 255 00:10:32,001 --> 00:10:33,000 a brief window of time 256 00:10:33,001 --> 00:10:35,000 before powerful currents 257 00:10:35,001 --> 00:10:37,000 threaten to sweep us away. 258 00:10:42,000 --> 00:10:44,500 We'Re looking for one of the 259 00:10:44,501 --> 00:10:46,999 oldest organisms on our planet, 260 00:10:47,000 --> 00:10:49,000 but as we descend, there is not 261 00:10:49,001 --> 00:10:51,000 much sign of life. 262 00:10:56,000 --> 00:10:58,000 Could it be hiding 263 00:10:58,001 --> 00:11:00,000 behind these strange rocks? 264 00:11:02,000 --> 00:11:04,500 Actually these rocks are the 265 00:11:04,501 --> 00:11:07,000 very things I'Ve come to see. 266 00:11:16,000 --> 00:11:18,999 They'Re called stromatolites, 267 00:11:19,000 --> 00:11:20,500 and believe it or not, 268 00:11:20,501 --> 00:11:22,000 they'Re alive. 269 00:11:25,000 --> 00:11:26,999 You can'T see them, 270 00:11:27,000 --> 00:11:28,500 but just beneath the surface 271 00:11:28,501 --> 00:11:29,999 of these boulders 272 00:11:30,000 --> 00:11:32,999 is a thin coating of bacteria. 273 00:11:33,000 --> 00:11:35,000 Over thousands of years, 274 00:11:35,001 --> 00:11:36,999 these microbes accumulated 275 00:11:37,000 --> 00:11:39,000 layer after layer 276 00:11:39,001 --> 00:11:40,999 of mud and sand 277 00:11:41,000 --> 00:11:43,500 to build mounds 278 00:11:43,501 --> 00:11:45,999 up to eight feet tall. 279 00:11:46,000 --> 00:11:48,000 Today, living, growing 280 00:11:48,001 --> 00:11:49,999 stromatolites like these 281 00:11:50,000 --> 00:11:54,999 are extremely rare, 282 00:11:55,000 --> 00:11:57,000 but these precious examples hold 283 00:11:57,001 --> 00:11:58,999 the key to the evolution 284 00:11:59,000 --> 00:12:02,000 of virtually all complex life. 285 00:12:04,000 --> 00:12:06,000 I could stay down here 286 00:12:06,001 --> 00:12:07,999 for hours, 287 00:12:08,000 --> 00:12:10,000 - but the current is getting - stronger, 288 00:12:10,003 --> 00:12:11,500 And we don'T want to get pulled 289 00:12:11,501 --> 00:12:13,000 out to sea. 290 00:12:18,000 --> 00:12:19,999 That was amazing down there. 291 00:12:20,000 --> 00:12:21,000 The current really picked up. 292 00:12:21,001 --> 00:12:23,000 - It was ripping - through there, too. 293 00:12:23,003 --> 00:12:24,999 And that is actually why, 294 00:12:25,000 --> 00:12:26,500 important reason for why 295 00:12:26,501 --> 00:12:27,999 we have these stromatolites. 296 00:12:28,000 --> 00:12:29,500 What'S special about this spot 297 00:12:29,501 --> 00:12:30,999 that allows them to be here? 298 00:12:31,000 --> 00:12:32,500 Well, you noticed 299 00:12:32,501 --> 00:12:33,999 a very strong current? 300 00:12:34,000 --> 00:12:36,000 - We were being hauled along - by that current. 301 00:12:36,003 --> 00:12:38,000 REID: - And you also noticed 302 00:12:38,003 --> 00:12:39,500 There were sand waves that were 303 00:12:39,501 --> 00:12:40,999 going over the stromatolites. 304 00:12:41,000 --> 00:12:43,000 - That sand will actually bury - the stromatolites 305 00:12:43,001 --> 00:12:44,000 For months at a time. 306 00:12:44,001 --> 00:12:45,999 And then unbury them again. 307 00:12:46,000 --> 00:12:47,000 And unbury them again, 308 00:12:47,001 --> 00:12:49,000 - and that burial is - really important 309 00:12:49,003 --> 00:12:51,000 - To the existence - of the stromatolites. 310 00:12:51,003 --> 00:12:53,000 JOHNSON: 311 00:12:53,001 --> 00:12:54,999 When the sand is swept away, 312 00:12:55,000 --> 00:12:57,000 - the stromatolites are vulnerable - to seaweed and corals 313 00:12:57,001 --> 00:12:58,000 That block the sun. 314 00:12:58,001 --> 00:13:00,999 The sand protects them. 315 00:13:01,000 --> 00:13:02,500 REID: 316 00:13:01,000 --> 00:13:03,999 organisms, 317 00:13:02,501 --> 00:13:04,000 It keeps away the higher 318 00:13:04,000 --> 00:13:05,999 the seaweeds, the corals. 319 00:13:06,000 --> 00:13:07,500 In early earth, there were 320 00:13:07,501 --> 00:13:08,999 no corals and seaweeds 321 00:13:09,000 --> 00:13:10,999 to compete, so they actually had 322 00:13:11,000 --> 00:13:13,500 a much bigger territory, 323 00:13:13,501 --> 00:13:15,999 and they dominated the planet. 324 00:13:16,000 --> 00:13:17,000 For about 80% 325 00:13:17,001 --> 00:13:18,000 of earth history, 326 00:13:18,001 --> 00:13:21,000 stromatolites were kings. 327 00:13:22,000 --> 00:13:24,000 JOHNSON: 328 00:13:22,000 --> 00:13:25,999 to rule. 329 00:13:24,001 --> 00:13:26,000 That'S a long, long time 330 00:13:26,000 --> 00:13:28,000 - Stromatolites are the earliest - fossilized form of life 331 00:13:28,003 --> 00:13:29,999 We'Ve ever found. 332 00:13:30,000 --> 00:13:31,500 NOAH PLANAVSKY: 333 00:13:30,000 --> 00:13:32,999 is a fossil, 334 00:13:31,501 --> 00:13:33,000 What I'M holding in my hands 335 00:13:33,000 --> 00:13:34,000 - a stromatolite - from North America. 336 00:13:34,003 --> 00:13:36,000 - It'S two billion - years old, 337 00:13:36,001 --> 00:13:37,000 - Almost two billion - years old. 338 00:13:37,001 --> 00:13:38,001 Wow. 339 00:13:40,000 --> 00:13:42,000 - JOHNSON: - So how old do these things 340 00:13:40,000 --> 00:13:41,999 Actually get? 341 00:13:42,000 --> 00:13:44,000 PLANAVSKY: 342 00:13:42,000 --> 00:13:45,999 3.5 billion years old. 343 00:13:44,001 --> 00:13:46,000 The oldest examples we find are 344 00:13:46,000 --> 00:13:48,000 - JOHNSON: - 3.5 billion years... I love that. 345 00:13:48,003 --> 00:13:49,999 That'S time, man. 346 00:13:50,000 --> 00:13:51,000 3.5 is almost three quarters 347 00:13:51,000 --> 00:13:52,000 - of the entire history - of the planet. 348 00:13:52,003 --> 00:13:53,500 So these organisms 349 00:13:53,501 --> 00:13:54,999 have seen it all. 350 00:13:55,000 --> 00:13:56,500 PLANAVSKY: 351 00:13:55,000 --> 00:13:58,000 of life thriving on our planet. 352 00:13:56,501 --> 00:13:58,000 They'Re a continuous record 353 00:14:00,000 --> 00:14:01,500 JOHNSON: 354 00:14:00,000 --> 00:14:03,000 so successful? 355 00:14:01,501 --> 00:14:03,000 So why were stromatolites 356 00:14:07,000 --> 00:14:08,000 Three billion years ago, 357 00:14:08,001 --> 00:14:10,500 our planet was almost 358 00:14:10,501 --> 00:14:12,999 unrecognizable. 359 00:14:13,000 --> 00:14:15,000 Covered by enormous oceans, 360 00:14:15,001 --> 00:14:16,999 there were no continents, 361 00:14:17,000 --> 00:14:19,000 just hundreds of small 362 00:14:19,001 --> 00:14:20,999 volcanic islands 363 00:14:21,000 --> 00:14:22,500 belching out huge amounts 364 00:14:22,501 --> 00:14:24,000 of carbon dioxide... 365 00:14:27,000 --> 00:14:29,000 and even toxic substances 366 00:14:29,001 --> 00:14:31,000 like sulfur dioxide and arsenic. 367 00:14:35,000 --> 00:14:37,000 Most creatures today would 368 00:14:37,001 --> 00:14:38,999 suffocate in these conditions, 369 00:14:39,000 --> 00:14:40,500 but the microbes that built 370 00:14:40,501 --> 00:14:41,999 stromatolites 371 00:14:42,000 --> 00:14:45,999 used them to their advantage. 372 00:14:46,000 --> 00:14:47,000 PLANAVSKY: 373 00:14:46,000 --> 00:14:47,999 about these organisms 374 00:14:47,001 --> 00:14:48,000 The really clever thing 375 00:14:48,000 --> 00:14:49,500 is they developed 376 00:14:49,501 --> 00:14:50,999 a way to thrive 377 00:14:51,000 --> 00:14:52,000 in the conditions back then, 378 00:14:52,001 --> 00:14:54,000 - in an atmosphere that would have - been toxic to life 379 00:14:54,003 --> 00:14:56,999 As we know it today. 380 00:14:57,000 --> 00:14:58,000 JOHNSON: 381 00:14:58,001 --> 00:14:59,001 But how did they do it? 382 00:15:02,000 --> 00:15:03,500 To find out, Noah and I wade 383 00:15:03,501 --> 00:15:04,999 into the slime 384 00:15:05,000 --> 00:15:07,000 of this shallow lake. 385 00:15:12,000 --> 00:15:14,999 This stuff is slippery, man. 386 00:15:15,000 --> 00:15:16,000 JOHNSON: 387 00:15:15,000 --> 00:15:16,999 with bacteria, 388 00:15:16,001 --> 00:15:17,000 This place is teeming 389 00:15:17,000 --> 00:15:18,500 similar to the ones that live 390 00:15:18,501 --> 00:15:19,999 on stromatolites. 391 00:15:20,000 --> 00:15:21,999 Oh, look at that. 392 00:15:22,000 --> 00:15:23,000 - PLANAVSKY: - The same type of organisms 393 00:15:23,003 --> 00:15:25,000 That form the stromatolites 394 00:15:25,001 --> 00:15:26,999 are forming these mats. 395 00:15:27,000 --> 00:15:28,500 Looks like kind of 396 00:15:28,501 --> 00:15:29,999 a nasty black lasagna. 397 00:15:30,000 --> 00:15:32,999 Smells bad too. 398 00:15:33,000 --> 00:15:34,500 There'S also some bubbles coming 399 00:15:34,501 --> 00:15:35,999 off in the water, seems like. 400 00:15:36,000 --> 00:15:37,000 - PLANAVSKY: - Let'S see what they are. 401 00:15:37,003 --> 00:15:38,999 So I have a gas probe here. 402 00:15:39,000 --> 00:15:41,000 Let'S bury it in the microbial 403 00:15:41,001 --> 00:15:42,999 mat here and see what we get. 404 00:15:43,000 --> 00:15:45,000 Very uppermost portion. 405 00:15:46,000 --> 00:15:47,999 And it'S what gas? 406 00:15:48,000 --> 00:15:49,999 Oxygen. 407 00:15:50,000 --> 00:15:51,000 Oxygen... this is coming 408 00:15:51,001 --> 00:15:52,000 out of the mat? 409 00:15:52,000 --> 00:15:53,000 Exactly. 410 00:15:53,001 --> 00:15:54,500 The waste product that 411 00:15:54,501 --> 00:15:55,999 transformed our planet 412 00:15:56,000 --> 00:15:57,000 is oxygen. 413 00:15:57,001 --> 00:15:58,500 JOHNSON: 414 00:15:58,501 --> 00:15:59,999 Oxygen a waste product? 415 00:16:00,000 --> 00:16:01,000 That'S what we breathe. 416 00:16:01,001 --> 00:16:04,000 But these little microbes do 417 00:16:04,001 --> 00:16:06,999 the opposite: 418 00:16:07,000 --> 00:16:08,500 They take in carbon dioxide 419 00:16:08,501 --> 00:16:10,000 and water and release oxygen. 420 00:16:15,000 --> 00:16:17,999 It'S called photosynthesis, 421 00:16:18,000 --> 00:16:19,000 the chemical reaction 422 00:16:19,001 --> 00:16:20,000 at the heart 423 00:16:20,001 --> 00:16:21,500 of every green plant alive 424 00:16:21,501 --> 00:16:23,000 on earth today. 425 00:16:26,000 --> 00:16:27,500 This was the contribution 426 00:16:27,501 --> 00:16:28,999 of the stromatolite bacteria 427 00:16:29,000 --> 00:16:30,000 to early Earth. 428 00:16:32,000 --> 00:16:34,500 In a place filled with volcanoes 429 00:16:34,501 --> 00:16:36,999 and water, 430 00:16:37,000 --> 00:16:38,500 over the course 431 00:16:38,501 --> 00:16:39,999 of more than two billion years, 432 00:16:40,000 --> 00:16:41,999 they pumped out so much oxygen 433 00:16:42,000 --> 00:16:43,500 that the atmosphere changed from 434 00:16:43,501 --> 00:16:44,999 what would have been 435 00:16:45,000 --> 00:16:46,999 a deadly poison for us 436 00:16:47,000 --> 00:16:48,500 into something that made it 437 00:16:48,501 --> 00:16:49,999 possible 438 00:16:50,000 --> 00:16:53,000 for life as we know it to exist. 439 00:16:59,000 --> 00:17:01,000 - So these things didn'T only - just live in their environment, 440 00:17:01,003 --> 00:17:03,000 - They actually transformed - the environment 441 00:17:03,003 --> 00:17:05,000 - And made it livable - for other things. 442 00:17:05,001 --> 00:17:06,001 Absolutely. 443 00:17:08,000 --> 00:17:10,000 JOHNSON: 444 00:17:10,001 --> 00:17:11,999 It was a critical turning point. 445 00:17:12,000 --> 00:17:14,000 Now a new kind of lifeform could 446 00:17:14,001 --> 00:17:15,999 finally join the party: 447 00:17:16,000 --> 00:17:18,500 Creatures that didn'T produce 448 00:17:18,501 --> 00:17:21,000 oxygen, but instead consumed it. 449 00:17:28,000 --> 00:17:30,500 About 640 million years ago, 450 00:17:30,501 --> 00:17:32,999 complex life took off, 451 00:17:33,000 --> 00:17:36,500 with the evolution of primitive 452 00:17:36,501 --> 00:17:39,999 animals like sponges, 453 00:17:40,000 --> 00:17:41,000 followed a little later 454 00:17:41,001 --> 00:17:43,500 by a group of jellyfish-like 455 00:17:43,501 --> 00:17:45,999 creatures called Cnidaria, 456 00:17:46,000 --> 00:17:48,000 - the first animals to possess - nerves and muscles. 457 00:17:51,000 --> 00:17:54,000 Over millions of years, 458 00:17:54,001 --> 00:17:56,999 life grew ever more complex. 459 00:17:57,000 --> 00:18:00,000 Fish got a skull and backbone 460 00:18:00,001 --> 00:18:02,999 420 million years ago. 461 00:18:03,000 --> 00:18:06,000 By this time, land had emerged, 462 00:18:06,001 --> 00:18:08,999 so it wasn'T long 463 00:18:09,000 --> 00:18:11,000 - before the first amphibians - hauled themselves 464 00:18:11,003 --> 00:18:13,000 Out of the water 465 00:18:13,001 --> 00:18:14,999 and onto the shore. 466 00:18:15,000 --> 00:18:17,000 This led to the evolution 467 00:18:17,001 --> 00:18:18,999 of reptiles, 468 00:18:19,000 --> 00:18:22,000 and then, more than 200 million 469 00:18:22,001 --> 00:18:25,000 years ago, to the dinosaurs. 470 00:18:29,000 --> 00:18:31,000 Which brings us right back 471 00:18:31,001 --> 00:18:32,999 to where we started... 472 00:18:33,000 --> 00:18:35,999 the big mystery. 473 00:18:36,000 --> 00:18:37,999 What was it about this continent 474 00:18:38,000 --> 00:18:39,500 that allowed so many kinds 475 00:18:39,501 --> 00:18:41,000 of dinosaurs to thrive? 476 00:18:50,000 --> 00:18:52,500 You can find one clue right 477 00:18:52,501 --> 00:18:54,999 smack in the middle of the U.S., 478 00:18:55,000 --> 00:18:57,000 in the Great Plains 479 00:18:57,001 --> 00:18:59,000 of central North America. 480 00:19:12,000 --> 00:19:13,000 For most people, 481 00:19:13,001 --> 00:19:14,500 a drive across the Great Plains 482 00:19:14,501 --> 00:19:16,000 is an exercise in boredom. 483 00:19:20,000 --> 00:19:21,999 For me it'S just the opposite. 484 00:19:22,000 --> 00:19:23,500 As a geologist I think about 485 00:19:23,501 --> 00:19:24,999 what'S beneath the plains, 486 00:19:25,000 --> 00:19:26,500 the stories that lie 487 00:19:26,501 --> 00:19:28,000 beneath the prairie. 488 00:19:43,000 --> 00:19:45,000 Just outside the town of Oakley 489 00:19:45,001 --> 00:19:46,999 in western Kansas, 490 00:19:47,000 --> 00:19:48,500 some strange but spectacular 491 00:19:48,501 --> 00:19:49,999 shapes burst up 492 00:19:50,000 --> 00:19:52,000 out of the plains. 493 00:19:55,000 --> 00:19:58,000 They'Re called Monument Rocks. 494 00:20:00,000 --> 00:20:02,000 This place is so cool. 495 00:20:04,000 --> 00:20:06,000 The story goes that early 496 00:20:06,001 --> 00:20:07,999 settlers crossing the plains 497 00:20:08,000 --> 00:20:09,500 used these as landmarks 498 00:20:09,501 --> 00:20:11,000 to help them navigate. 499 00:20:24,000 --> 00:20:26,000 - One of the most amazing things - about this place 500 00:20:26,003 --> 00:20:27,999 Is how much time it represents. 501 00:20:28,000 --> 00:20:30,000 Just one inch of this chalk 502 00:20:30,001 --> 00:20:31,999 is 700 years. 503 00:20:32,000 --> 00:20:34,000 That means that a foot of the 504 00:20:34,001 --> 00:20:35,999 chalk is 8,400 years, 505 00:20:36,000 --> 00:20:38,000 - or roughly the entire duration - of human civilization. 506 00:20:38,003 --> 00:20:39,500 There'S about 40 feet of this 507 00:20:39,501 --> 00:20:40,999 stuff above me, 508 00:20:41,000 --> 00:20:42,500 and there'S another 300 feet 509 00:20:42,501 --> 00:20:43,999 below me. 510 00:20:44,000 --> 00:20:45,500 There'S literally millions 511 00:20:45,501 --> 00:20:46,999 of years represented 512 00:20:47,000 --> 00:20:48,000 in this one place. 513 00:20:54,000 --> 00:20:55,000 It'S a snapshot of a time 514 00:20:55,001 --> 00:20:57,500 when North America was going 515 00:20:57,501 --> 00:20:59,999 through some major changes. 516 00:21:00,000 --> 00:21:01,500 This place is filled 517 00:21:01,501 --> 00:21:03,000 with fossils. 518 00:21:05,000 --> 00:21:06,999 Hey, Chuck! 519 00:21:07,000 --> 00:21:08,000 Long time no see. 520 00:21:08,000 --> 00:21:09,000 Good seeing you. 521 00:21:09,001 --> 00:21:10,999 Hey, Barb, how are you doing? 522 00:21:11,000 --> 00:21:12,999 Good to see you. 523 00:21:13,000 --> 00:21:14,000 JOHNSON: 524 00:21:13,000 --> 00:21:14,999 at finding them 525 00:21:14,001 --> 00:21:15,000 And nobody is better 526 00:21:15,000 --> 00:21:16,000 than Chuck Bonner 527 00:21:16,001 --> 00:21:17,000 and rbara Shelton, 528 00:21:17,001 --> 00:21:19,000 who'Ve hunted for fossils in 529 00:21:19,001 --> 00:21:20,999 these rocks for over 40 years. 530 00:21:21,000 --> 00:21:22,000 - Let'S go find - some fossils. 531 00:21:22,001 --> 00:21:23,000 All right, - sound good. 532 00:21:23,003 --> 00:21:25,000 Well, come on. 533 00:21:27,000 --> 00:21:29,000 JOHNSON: 534 00:21:27,000 --> 00:21:30,999 by, they offered to show me 535 00:21:29,001 --> 00:21:31,000 When I told them I was coming 536 00:21:31,000 --> 00:21:32,999 their newest discovery. 537 00:21:33,000 --> 00:21:34,000 That'S pretty cool. 538 00:21:38,000 --> 00:21:39,000 - How did you find - this thing, Chuck? 539 00:21:39,003 --> 00:21:40,500 Well, I was searching along 540 00:21:40,501 --> 00:21:41,999 these slopes here 541 00:21:42,000 --> 00:21:43,000 and found some 542 00:21:43,001 --> 00:21:44,000 big bones sticking out. 543 00:21:44,000 --> 00:21:45,000 That'S cool. 544 00:21:45,001 --> 00:21:47,000 - What did you think when you - first saw this, Barb? 545 00:21:47,003 --> 00:21:49,000 - Lot of digging, - that'S what I think. 546 00:21:49,003 --> 00:21:51,000 - Let'S put a little - water on here, huh? 547 00:21:51,003 --> 00:21:53,999 Yeah, let'S bring it to life. 548 00:21:54,000 --> 00:21:56,500 JOHNSON: 549 00:21:54,000 --> 00:21:58,999 with some major-league teeth, 550 00:21:56,501 --> 00:21:59,000 A little water reveals a skull 551 00:21:59,000 --> 00:22:02,999 no question a vicious predator. 552 00:22:03,000 --> 00:22:04,000 But this was no dinosaur. 553 00:22:07,000 --> 00:22:08,500 These jaws belong to an 554 00:22:08,501 --> 00:22:09,999 80-million-year-old fish 555 00:22:10,000 --> 00:22:13,999 called Xiphactinus. 556 00:22:14,000 --> 00:22:15,000 This jaw is huge. 557 00:22:15,001 --> 00:22:17,000 - This must have been - an immense fish. 558 00:22:17,003 --> 00:22:19,999 Probably close to 14 feet long. 559 00:22:20,000 --> 00:22:23,999 14-foot-long fish in Kansas. 560 00:22:24,000 --> 00:22:25,500 Name me a living 561 00:22:25,501 --> 00:22:26,999 14-foot-long fish. 562 00:22:27,000 --> 00:22:28,500 Well, if you count the bill 563 00:22:28,501 --> 00:22:29,999 on a marlin, maybe. 564 00:22:30,000 --> 00:22:31,000 We'Re in Kansas, Chuck. 565 00:22:31,001 --> 00:22:32,500 So a 14-foot-long fish 566 00:22:32,501 --> 00:22:33,999 in Kansas? 567 00:22:34,000 --> 00:22:35,000 Yeah, sure. 568 00:22:40,000 --> 00:22:42,000 - JOHNSON: - What is this ancient marine 569 00:22:40,000 --> 00:22:41,999 Predator doing 570 00:22:42,000 --> 00:22:44,000 750 miles 571 00:22:44,001 --> 00:22:46,000 from the nearest ocean? 572 00:22:54,000 --> 00:22:55,000 Well, it turns out, 573 00:22:55,001 --> 00:22:57,000 80 million years ago, 574 00:22:57,001 --> 00:22:58,999 the ocean was here, 575 00:22:59,000 --> 00:23:01,000 right on top of Kansas. 576 00:23:04,000 --> 00:23:06,000 - It was teeming with mighty - sea creatures 577 00:23:06,003 --> 00:23:07,500 Like Chuck and Barbara'S 578 00:23:07,501 --> 00:23:09,000 14-foot Xiphactinus. 579 00:23:16,000 --> 00:23:18,000 - But it wasn'T just Kansas - that was covered in water. 580 00:23:23,000 --> 00:23:25,999 About 130 million years ago, 581 00:23:26,000 --> 00:23:28,000 the ocean began to invade. 582 00:23:28,001 --> 00:23:29,999 North America. 583 00:23:30,000 --> 00:23:31,500 Water flooded in and formed 584 00:23:31,501 --> 00:23:32,999 a massive inland sea 585 00:23:33,000 --> 00:23:37,000 up to a thousand miles wide. 586 00:23:40,000 --> 00:23:41,500 It split the continent 587 00:23:41,501 --> 00:23:42,999 into two landmasses: 588 00:23:43,000 --> 00:23:45,500 Laramidia in the west 589 00:23:45,501 --> 00:23:48,000 and Appalachia in the east. 590 00:23:52,000 --> 00:23:53,500 The big inland sea would have 591 00:23:53,501 --> 00:23:54,999 huge consequences 592 00:23:55,000 --> 00:23:56,999 for life on our continent, 593 00:23:57,000 --> 00:23:58,500 especially. 594 00:23:58,501 --> 00:24:00,000 North America'S dinosaurs. 595 00:24:13,000 --> 00:24:15,999 Back in the Kaiparowits in Utah, 596 00:24:16,000 --> 00:24:17,000 where scientists have discovered 597 00:24:17,001 --> 00:24:19,000 - an amazing new collection - of dinosaurs, 598 00:24:19,003 --> 00:24:21,000 Paleontologist Joe Sertich shows 599 00:24:21,001 --> 00:24:22,999 me his latest find 600 00:24:23,000 --> 00:24:25,000 from this extraordinary 601 00:24:25,001 --> 00:24:26,999 dinosaur graveyard. 602 00:24:27,000 --> 00:24:29,000 - That'S pretty clearly - a horn. 603 00:24:29,001 --> 00:24:30,000 SERTICH: - Yep. 604 00:24:30,003 --> 00:24:32,000 - Here you can see where - the eye would have been. 605 00:24:32,003 --> 00:24:34,000 - There'S a large section - of the horn coming off. 606 00:24:34,003 --> 00:24:36,000 There'S the tip 607 00:24:36,001 --> 00:24:37,999 of the horn there. 608 00:24:38,000 --> 00:24:40,000 It'S starting to look more and 609 00:24:40,001 --> 00:24:41,999 more like a brand new species. 610 00:24:42,000 --> 00:24:43,999 This is so Jurassic Park. 611 00:24:44,000 --> 00:24:45,000 It is. 612 00:24:49,000 --> 00:24:50,500 JOHNSON: 613 00:24:49,000 --> 00:24:51,999 are remarkably different 614 00:24:50,501 --> 00:24:52,000 The new dinosaurs here 615 00:24:52,000 --> 00:24:53,500 from other dinosaurs that lived 616 00:24:53,501 --> 00:24:55,000 farther north at the same time. 617 00:24:58,000 --> 00:24:59,000 So what is it 618 00:24:59,001 --> 00:25:00,001 with all this diversity? 619 00:25:03,000 --> 00:25:05,000 - From around a hundred million - years ago, 620 00:25:05,003 --> 00:25:07,000 Our continent was split down 621 00:25:07,001 --> 00:25:09,000 the middle by the inland sea. 622 00:25:10,000 --> 00:25:12,000 Over time, sea levels changed, 623 00:25:12,001 --> 00:25:13,999 shifting the coastline 624 00:25:14,000 --> 00:25:16,000 back and forth all the time. 625 00:25:18,000 --> 00:25:20,000 And keeping the dinosaurs of. 626 00:25:20,001 --> 00:25:22,000 North America on their toes. 627 00:25:27,000 --> 00:25:28,500 With their home turf 628 00:25:28,501 --> 00:25:29,999 constantly changing, 629 00:25:30,000 --> 00:25:31,500 groups of dinosaurs evolved 630 00:25:31,501 --> 00:25:32,999 over time and adapted 631 00:25:33,000 --> 00:25:36,000 to their local surroundings. 632 00:25:46,000 --> 00:25:47,000 Joe and his colleagues 633 00:25:47,001 --> 00:25:48,000 have collected 634 00:25:48,001 --> 00:25:50,000 an amazing variety of dinosaurs 635 00:25:50,001 --> 00:25:51,999 and fossil plants, 636 00:25:52,000 --> 00:25:53,000 showing how different 637 00:25:53,001 --> 00:25:54,000 environments 638 00:25:54,001 --> 00:25:56,000 drove dinosaur diversity. 639 00:26:01,000 --> 00:26:02,000 So what you'Re saying 640 00:26:02,001 --> 00:26:03,500 is that these different 641 00:26:03,501 --> 00:26:04,999 environments along the coastline 642 00:26:05,000 --> 00:26:06,000 create different landscapes 643 00:26:06,001 --> 00:26:07,999 for dinosaurs to evolve in. 644 00:26:08,000 --> 00:26:09,000 Exactly. 645 00:26:09,000 --> 00:26:10,999 Different ecosystems 646 00:26:09,001 --> 00:26:11,000 - SERTICH: - We suspect that these 647 00:26:11,000 --> 00:26:12,000 are driving dinosaur 648 00:26:12,001 --> 00:26:13,000 diversification 649 00:26:13,001 --> 00:26:14,500 as dinosaurs and other animals 650 00:26:14,501 --> 00:26:15,999 adapt to their local conditions. 651 00:26:16,000 --> 00:26:18,000 - And that makes North America - a dinosaur factory. 652 00:26:18,003 --> 00:26:20,000 Exactly. 653 00:26:24,000 --> 00:26:25,000 JOHNSON: 654 00:26:25,001 --> 00:26:26,000 As a paleontologist, 655 00:26:26,001 --> 00:26:28,000 it'S really exciting to think 656 00:26:28,001 --> 00:26:29,999 that 75 million years ago, 657 00:26:30,000 --> 00:26:32,000 - this land was full of dinosaurs - of every description. 658 00:26:35,000 --> 00:26:36,500 They all lived along 659 00:26:36,501 --> 00:26:37,999 this huge inland sea 660 00:26:38,000 --> 00:26:39,500 that split America down the 661 00:26:39,501 --> 00:26:40,999 middle and created a whole bunch 662 00:26:41,000 --> 00:26:42,999 of different habitats. 663 00:26:43,000 --> 00:26:44,500 But 70 million years ago, 664 00:26:44,501 --> 00:26:45,999 something dramatic happened. 665 00:26:46,000 --> 00:26:49,000 The great North American seaway 666 00:26:49,001 --> 00:26:51,999 began to drain away. 667 00:26:52,000 --> 00:26:54,500 So what happened to make this 668 00:26:54,501 --> 00:26:56,999 enormous body of water 669 00:26:57,000 --> 00:26:59,000 totally vanish? 670 00:27:05,000 --> 00:27:06,999 To solve that mystery, 671 00:27:07,000 --> 00:27:08,500 I'Ve got to head east 672 00:27:08,501 --> 00:27:10,000 from Utah to Colorado. 673 00:27:12,000 --> 00:27:14,000 This place was also once covered 674 00:27:14,001 --> 00:27:16,000 by the vast inland sea. 675 00:27:24,000 --> 00:27:26,000 With a big sky overhead, 676 00:27:26,001 --> 00:27:27,999 you can see for miles. 677 00:27:28,000 --> 00:27:30,000 - Ah, it'S really great views - up here. 678 00:27:30,003 --> 00:27:32,999 Three sixty. 679 00:27:33,000 --> 00:27:35,000 But I didn'T climb this hill 680 00:27:35,001 --> 00:27:36,999 just for the view. 681 00:27:37,000 --> 00:27:39,000 I'M on the hunt for some 682 00:27:39,001 --> 00:27:40,999 strange-looking objects 683 00:27:41,000 --> 00:27:42,500 that I'M hoping to find 684 00:27:42,501 --> 00:27:44,000 right under my feet. 685 00:27:50,000 --> 00:27:53,000 - That'S what I'M looking for, - but it'S not a very good one. 686 00:27:55,000 --> 00:27:57,000 These hollowed-out rocks are 687 00:27:57,001 --> 00:27:58,999 clues that help explain 688 00:27:59,000 --> 00:28:00,500 why North America'S giant 689 00:28:00,501 --> 00:28:02,000 inland sea disappeared. 690 00:28:08,000 --> 00:28:09,200 Here'S a pretty good one. 691 00:28:16,000 --> 00:28:19,500 After a rain, the water pools 692 00:28:19,501 --> 00:28:22,999 in them like this 693 00:28:23,000 --> 00:28:25,000 - and the birds come and bathe - in these things, 694 00:28:25,003 --> 00:28:26,500 And the locals call these things 695 00:28:26,501 --> 00:28:27,999 birdbaths, 696 00:28:28,000 --> 00:28:30,000 - but they'Re actually something - much more interesting than that. 697 00:28:32,000 --> 00:28:34,000 JOHNSON: 698 00:28:32,000 --> 00:28:35,999 fossils of ancient shellfish 699 00:28:34,001 --> 00:28:36,000 These rocks once contained 700 00:28:36,000 --> 00:28:38,999 called ammonites. 701 00:28:39,000 --> 00:28:41,000 - You can pretty clearly see - the shape of the shell 702 00:28:41,003 --> 00:28:42,999 If you start in the center here, 703 00:28:43,000 --> 00:28:44,000 and the spiral goes all 704 00:28:44,001 --> 00:28:45,000 the way out. 705 00:28:45,001 --> 00:28:46,500 And in the middle, there would 706 00:28:46,501 --> 00:28:47,999 have been a series of chambers. 707 00:28:48,000 --> 00:28:49,500 The fleshy part of the animal 708 00:28:49,501 --> 00:28:50,999 would have stuck out 709 00:28:51,000 --> 00:28:52,000 of the shell here 710 00:28:52,001 --> 00:28:53,000 and it would have looked 711 00:28:53,000 --> 00:28:54,000 - something like a squid - or an octopus. 712 00:28:54,003 --> 00:28:56,000 For more than 40 million years, 713 00:28:56,001 --> 00:28:57,999 North America'S inland sea 714 00:28:58,000 --> 00:29:00,500 was filled with giant ammonites 715 00:29:00,501 --> 00:29:03,000 like these. 716 00:29:06,000 --> 00:29:08,000 - But it'S one thing to find - marine fossils 717 00:29:08,003 --> 00:29:09,999 In the flatlands of Kansas. 718 00:29:10,000 --> 00:29:12,500 It'S another to find them in 719 00:29:12,501 --> 00:29:15,000 the mountains high above Denver. 720 00:29:17,000 --> 00:29:18,500 The big question here is, 721 00:29:18,501 --> 00:29:19,999 what'S going on? 722 00:29:20,000 --> 00:29:21,500 But I'Ve got an altimeter here 723 00:29:21,501 --> 00:29:22,999 and the altimeter says 724 00:29:23,000 --> 00:29:25,000 that I'M 7,703 feet 725 00:29:25,001 --> 00:29:26,999 above sea level. 726 00:29:27,000 --> 00:29:29,000 That means that something took 727 00:29:29,001 --> 00:29:30,999 marine creatures 728 00:29:31,000 --> 00:29:32,999 and brought them to an elevation 729 00:29:33,000 --> 00:29:34,000 - that'S more than a mile above - sea level. 730 00:29:38,000 --> 00:29:39,999 It'S the same thing 731 00:29:40,000 --> 00:29:42,000 - that made North America'S - inland sea disappear. 732 00:29:51,000 --> 00:29:52,999 And driving it all 733 00:29:53,000 --> 00:29:54,500 is the constant motion 734 00:29:54,501 --> 00:29:56,000 of the ground itself. 735 00:29:59,000 --> 00:30:01,000 Because the surface of our 736 00:30:01,001 --> 00:30:02,999 planet is broken up into pieces 737 00:30:03,000 --> 00:30:05,000 that slowly slide along a 738 00:30:05,001 --> 00:30:06,999 conveyor belt of hot rock 739 00:30:07,000 --> 00:30:08,500 miles beneath us 740 00:30:08,501 --> 00:30:10,000 at about two inches a year. 741 00:30:15,000 --> 00:30:17,999 Around 70 million years ago, 742 00:30:18,000 --> 00:30:19,500 a piece of crust under the. 743 00:30:19,501 --> 00:30:20,999 Pacific Ocean was diving down 744 00:30:21,000 --> 00:30:23,000 at the western edge 745 00:30:23,001 --> 00:30:25,000 of North America. 746 00:30:26,000 --> 00:30:28,000 We think that it then began to 747 00:30:28,001 --> 00:30:29,999 slide right under the continent, 748 00:30:30,000 --> 00:30:33,000 making it rise, forcing it up 749 00:30:33,001 --> 00:30:35,999 inch by inch 750 00:30:36,000 --> 00:30:40,000 to create an icon of the. 751 00:30:40,001 --> 00:30:43,999 North American landscape... 752 00:30:44,000 --> 00:30:45,000 the Rocky Mountains. 753 00:30:51,000 --> 00:30:52,500 The birth of this majestic 754 00:30:52,501 --> 00:30:53,999 mountain range 755 00:30:54,000 --> 00:30:56,500 was the death of North America'S 756 00:30:56,501 --> 00:30:59,000 great inland sea. 757 00:31:01,000 --> 00:31:03,000 As the Rockies began to rise, 758 00:31:03,001 --> 00:31:04,999 the land under the Inland Sea 759 00:31:05,000 --> 00:31:07,000 was forced up and 760 00:31:07,001 --> 00:31:08,999 all of its waters drained 761 00:31:09,000 --> 00:31:10,500 into what is now the Arctic. 762 00:31:10,501 --> 00:31:12,000 Ocean and the Gulf of Mexico. 763 00:31:17,000 --> 00:31:18,500 This left the marine creatures 764 00:31:18,501 --> 00:31:19,999 living in the Inland Sea 765 00:31:20,000 --> 00:31:23,999 literally high and dry. 766 00:31:24,000 --> 00:31:26,000 - It'S mind-boggling to think that - the bottom of the sea 767 00:31:26,003 --> 00:31:27,500 Could be found at the top 768 00:31:27,501 --> 00:31:28,999 of a mountain range, 769 00:31:29,000 --> 00:31:31,000 - but here are all these fossils - that say that it'S so. 770 00:31:36,000 --> 00:31:38,500 The forces under the earth are 771 00:31:38,501 --> 00:31:41,000 so slow, but so relentless. 772 00:31:43,000 --> 00:31:44,999 Over millions of years, 773 00:31:45,000 --> 00:31:47,000 they completely altered the 774 00:31:47,001 --> 00:31:48,999 shape and form of the continent 775 00:31:49,000 --> 00:31:51,000 and changed the fates of the 776 00:31:51,001 --> 00:31:52,999 millions of plants and animals 777 00:31:53,000 --> 00:31:54,000 that were living there. 778 00:31:57,000 --> 00:31:59,000 From the very beginning, rocks 779 00:31:59,001 --> 00:32:01,000 and life have been intertwined. 780 00:32:03,000 --> 00:32:04,500 But this process doesn'T always 781 00:32:04,501 --> 00:32:06,000 move slowly. 782 00:32:11,000 --> 00:32:12,500 And change doesn'T always come 783 00:32:12,501 --> 00:32:13,999 from below, 784 00:32:14,000 --> 00:32:16,500 as our old friends the dinosaurs 785 00:32:16,501 --> 00:32:19,000 were about to find out. 786 00:32:27,000 --> 00:32:28,500 So I pack my bags 787 00:32:28,501 --> 00:32:30,000 and head north... 788 00:32:33,000 --> 00:32:35,000 to track down a 66-million- 789 00:32:35,001 --> 00:32:36,999 year-old smoking gun. 790 00:32:37,000 --> 00:32:39,000 Thanks so much. 791 00:32:55,000 --> 00:32:57,000 - These are the North Dakota - Badlands. 792 00:33:01,000 --> 00:33:02,500 Thousands of square miles 793 00:33:02,501 --> 00:33:04,000 of arid gullies and buttes. 794 00:33:08,000 --> 00:33:09,000 I'M driving deep 795 00:33:09,001 --> 00:33:10,000 into the badlands here, 796 00:33:10,001 --> 00:33:11,500 on what is called the state 797 00:33:11,501 --> 00:33:12,999 highway, but it'S actually 798 00:33:13,000 --> 00:33:14,999 a gravel road. 799 00:33:15,000 --> 00:33:17,000 - And right around us here is - what'S called 800 00:33:17,001 --> 00:33:18,000 The Hell Creek formation. 801 00:33:18,001 --> 00:33:19,500 It'S a 300-foot-thick layer of 802 00:33:19,501 --> 00:33:20,999 rock that stretches 803 00:33:21,000 --> 00:33:22,999 over four states, 804 00:33:23,000 --> 00:33:25,000 and it'S a spot that I just keep 805 00:33:25,001 --> 00:33:27,000 coming back to again and again. 806 00:33:29,000 --> 00:33:30,000 And here'S a cow. 807 00:33:30,001 --> 00:33:31,001 I'M about to hit. 808 00:33:50,000 --> 00:33:52,000 - I just can'Tet enough - of this place, 809 00:33:52,003 --> 00:33:55,000 Because hidden in these hills is 810 00:33:55,001 --> 00:33:57,999 evidence of an earth-shaking, 811 00:33:58,000 --> 00:34:00,000 life-changing event. 812 00:34:04,000 --> 00:34:05,500 To find it, I'M going to have 813 00:34:05,501 --> 00:34:07,000 to do a little digging. 814 00:34:26,000 --> 00:34:27,500 I'Ve actually got a couple of 815 00:34:27,501 --> 00:34:28,999 pieces of fossil charcoal here, 816 00:34:29,000 --> 00:34:31,000 and that'S pretty common in 817 00:34:31,001 --> 00:34:32,999 these layered rocks... 818 00:34:33,000 --> 00:34:34,000 you find evidence 819 00:34:34,001 --> 00:34:35,000 of the ancient world, 820 00:34:35,001 --> 00:34:36,500 whether it'S the mud at a bottom 821 00:34:36,501 --> 00:34:37,999 of a lake, 822 00:34:38,000 --> 00:34:39,000 the coal from a swamp, 823 00:34:39,001 --> 00:34:40,500 or the charcoal 824 00:34:40,501 --> 00:34:41,999 from an ancient forest fire. 825 00:34:42,000 --> 00:34:44,999 And every layer used to be 826 00:34:45,000 --> 00:34:47,000 the surface of the earth 827 00:34:47,001 --> 00:34:48,999 at a certain point in time. 828 00:34:49,000 --> 00:34:50,000 Now there'S a stack 829 00:34:50,001 --> 00:34:51,000 of these layers, 830 00:34:51,001 --> 00:34:53,000 and I'M looking for one layer 831 00:34:53,001 --> 00:34:54,999 in particular... 832 00:34:55,000 --> 00:34:57,500 one very thin, one very special, 833 00:34:57,501 --> 00:35:00,000 one very scary layer. 834 00:35:13,000 --> 00:35:14,999 After a few minutes of digging, 835 00:35:15,000 --> 00:35:17,500 I find the 66-million-year-old 836 00:35:17,501 --> 00:35:20,000 layer I'Ve been searching for. 837 00:35:23,000 --> 00:35:26,999 There it is, right along here. 838 00:35:27,000 --> 00:35:28,500 It'S a little rusty orange 839 00:35:28,501 --> 00:35:29,999 layer. 840 00:35:30,000 --> 00:35:33,000 It doesn'T look like much, 841 00:35:33,001 --> 00:35:36,000 but this layer is Armageddon. 842 00:35:38,000 --> 00:35:40,000 To show you why, 843 00:35:40,001 --> 00:35:42,000 I need to get in closer. 844 00:35:45,000 --> 00:35:46,500 What I'Ll do is just set up 845 00:35:46,501 --> 00:35:48,000 my handy-dandy field microscope. 846 00:36:07,000 --> 00:36:09,000 - I'M looking at this layer - under the microscope 847 00:36:09,003 --> 00:36:11,000 - And what I'M seeing is that - it'S actually composed 848 00:36:11,003 --> 00:36:13,000 Of little round balls 849 00:36:13,001 --> 00:36:14,999 about a millimeter in diameter. 850 00:36:15,000 --> 00:36:17,000 And these things are what used 851 00:36:17,001 --> 00:36:18,999 to be little glass beads. 852 00:36:19,000 --> 00:36:20,500 So what you'Ve got basically is 853 00:36:20,501 --> 00:36:21,999 some sort of geologic phenomenon 854 00:36:22,000 --> 00:36:24,000 that'S dropping beads of glass 855 00:36:24,001 --> 00:36:26,000 onto an ancient landscape. 856 00:36:27,000 --> 00:36:28,500 So what could have 857 00:36:28,501 --> 00:36:29,999 happened here? 858 00:36:30,000 --> 00:36:32,000 - One way you get a layer of glass - beads on a landscape 859 00:36:32,003 --> 00:36:33,999 Is to have a violent event 860 00:36:34,000 --> 00:36:36,000 that melts rock and blasts it 861 00:36:36,001 --> 00:36:37,999 in the air. 862 00:36:38,000 --> 00:36:40,000 - As the molten rock flies through - the air, 863 00:36:40,003 --> 00:36:42,000 - It cools into glass and rains - down on the landscape 864 00:36:42,001 --> 00:36:43,001 As glass beads. 865 00:36:51,000 --> 00:36:52,500 If all we found in this layer 866 00:36:52,501 --> 00:36:53,999 were glass beads, 867 00:36:54,000 --> 00:36:56,000 the most likely 868 00:36:56,001 --> 00:36:57,999 explanation might be 869 00:36:58,000 --> 00:36:59,120 a massive volcanic eruption. 870 00:37:03,000 --> 00:37:05,000 - But there'S something else - hidden within this layer 871 00:37:05,001 --> 00:37:06,001 That changes the story... 872 00:37:10,000 --> 00:37:12,000 tiny crystals 873 00:37:12,001 --> 00:37:13,999 called shocked quartz. 874 00:37:14,000 --> 00:37:15,500 Quartz is an extremely 875 00:37:15,501 --> 00:37:16,999 common mineral. 876 00:37:17,000 --> 00:37:18,000 You can find it 877 00:37:18,001 --> 00:37:19,001 all over the planet. 878 00:37:21,000 --> 00:37:22,500 But when it shows up 879 00:37:22,501 --> 00:37:23,999 with these parallel lines 880 00:37:24,000 --> 00:37:25,500 as shocked quartz, 881 00:37:25,501 --> 00:37:26,999 that means it'S been exposed 882 00:37:27,000 --> 00:37:29,000 to huge amounts of energy... 883 00:37:31,000 --> 00:37:32,500 Like you get 884 00:37:32,501 --> 00:37:34,000 at nuclear test sites. 885 00:37:38,000 --> 00:37:39,500 But when this layer of earth 886 00:37:39,501 --> 00:37:40,999 was laid down, 887 00:37:41,000 --> 00:37:43,000 there were no atomic bombs. 888 00:37:47,000 --> 00:37:48,000 There was only one thing 889 00:37:48,001 --> 00:37:49,000 that could have made 890 00:37:49,001 --> 00:37:50,500 a big enough bang 891 00:37:50,501 --> 00:37:52,000 to shock quartz. 892 00:37:54,000 --> 00:37:56,999 About 66 million years ago, 893 00:37:57,000 --> 00:38:00,000 an asteroid the size of Mount. 894 00:38:00,001 --> 00:38:03,000 Everest was headed for Earth. 895 00:38:06,000 --> 00:38:07,000 It entered the atmosphere 896 00:38:07,001 --> 00:38:09,000 at over 20 times the speed 897 00:38:09,001 --> 00:38:10,999 of a rifle bullet 898 00:38:11,000 --> 00:38:14,000 and exploded with more power 899 00:38:14,001 --> 00:38:16,999 than a billion atomic bombs, 900 00:38:17,000 --> 00:38:18,500 sending a superheated plume 901 00:38:18,501 --> 00:38:19,999 of vaporized rock 902 00:38:20,000 --> 00:38:22,999 shooting across North America 903 00:38:23,000 --> 00:38:24,000 and over a hundred miles 904 00:38:24,001 --> 00:38:25,001 up into space. 905 00:38:29,000 --> 00:38:30,500 This cloud of doom carried 906 00:38:30,501 --> 00:38:31,999 droplets of molten glass 907 00:38:32,000 --> 00:38:34,000 and shocked quartz all the way 908 00:38:34,001 --> 00:38:35,999 to where I found them 909 00:38:36,000 --> 00:38:38,999 in North Dakota and beyond, 910 00:38:39,000 --> 00:38:41,000 - bringing death and destruction - to our planet. 911 00:38:47,000 --> 00:38:49,000 But what effect did it have 912 00:38:49,001 --> 00:38:51,000 on the dinosaurs? 913 00:38:54,000 --> 00:38:56,000 - For the last 30 years - it'S been pretty widely thought 914 00:38:56,003 --> 00:38:58,000 - That one of the main groups - of animals that were the victims 915 00:38:58,003 --> 00:39:00,000 Of this event 916 00:39:00,001 --> 00:39:01,999 were the dinosaurs. 917 00:39:02,000 --> 00:39:03,999 If this is the case, 918 00:39:04,000 --> 00:39:06,000 - it'S useful to have some - real scientific data. 919 00:39:18,000 --> 00:39:20,500 30 miles down the road is a guy 920 00:39:20,501 --> 00:39:22,999 who can help me with this. 921 00:39:23,000 --> 00:39:24,999 Tyler Lyson is a paleontologist 922 00:39:25,000 --> 00:39:26,500 who'S been digging up dinosaur 923 00:39:26,501 --> 00:39:27,999 fossils in these badlands 924 00:39:28,000 --> 00:39:29,000 for more than 20 years. 925 00:39:29,000 --> 00:39:30,000 - It'S been a long time, - buddy. 926 00:39:30,003 --> 00:39:31,999 Yeah, how'S it going? 927 00:39:32,000 --> 00:39:33,999 Always good in dinosaur land. 928 00:39:34,000 --> 00:39:35,000 What have you got going? 929 00:39:35,001 --> 00:39:36,999 Have a look at this. 930 00:39:37,000 --> 00:39:38,999 Here we have a thescelosaur. 931 00:39:39,000 --> 00:39:41,000 JOHNSON: 932 00:39:39,000 --> 00:39:42,999 dozens of dinosaur skeletons 933 00:39:41,001 --> 00:39:43,000 Tyler and his crew have pulled 934 00:39:43,000 --> 00:39:45,000 from these rocks, 935 00:39:45,001 --> 00:39:46,999 among them big names 936 00:39:47,000 --> 00:39:48,000 like triceratops 937 00:39:48,001 --> 00:39:49,000 and Tyrannosaurus rex. 938 00:39:49,001 --> 00:39:51,000 - All told, how many different - kinds of dinosaurs 939 00:39:51,001 --> 00:39:52,000 Have you found in this area? 940 00:39:52,000 --> 00:39:53,000 Two dozen. 941 00:39:53,001 --> 00:39:55,000 - We'Ve found all - the major players here. 942 00:39:55,003 --> 00:39:56,500 Just happens to be one 943 00:39:56,501 --> 00:39:57,999 of the best places in the world 944 00:39:58,000 --> 00:39:59,999 to find dinosaurs. 945 00:40:00,000 --> 00:40:01,999 It'S a rich, rich area. 946 00:40:02,000 --> 00:40:03,500 JOHNSON: 947 00:40:02,000 --> 00:40:04,999 these dinosaurs? 948 00:40:03,501 --> 00:40:05,000 But where do we find 949 00:40:05,000 --> 00:40:06,500 Are they below the impact layer 950 00:40:06,501 --> 00:40:07,999 or above? 951 00:40:08,000 --> 00:40:10,999 Before the asteroid struck? 952 00:40:11,000 --> 00:40:12,999 Or after? 953 00:40:13,000 --> 00:40:14,500 So where is the asteroid 954 00:40:14,501 --> 00:40:15,999 impact layer here? 955 00:40:16,000 --> 00:40:18,000 - It'S right at the layer - of that boulder right there. 956 00:40:21,000 --> 00:40:22,999 So what do you get below that? 957 00:40:23,000 --> 00:40:24,500 LYSON: 958 00:40:23,000 --> 00:40:25,999 really big dinosaurs. 959 00:40:24,501 --> 00:40:26,000 Well, we have some 960 00:40:26,000 --> 00:40:27,000 - We have the big plant-eating - dinosaurs 961 00:40:27,003 --> 00:40:30,000 Like triceratops, edmontosaurus, 962 00:40:30,001 --> 00:40:32,999 thescelosaurus. 963 00:40:33,000 --> 00:40:35,500 And then the thing that ate 964 00:40:35,501 --> 00:40:37,999 those dinosaurs, like T. Rex. 965 00:40:38,000 --> 00:40:39,000 JOHNSON: 966 00:40:38,000 --> 00:40:39,999 impact layer, 967 00:40:39,001 --> 00:40:40,000 So above the asteroid 968 00:40:40,000 --> 00:40:41,000 what do you get? 969 00:40:41,000 --> 00:40:45,999 we get crocodiles, some birds, 970 00:40:41,001 --> 00:40:43,500 LYSON: 971 00:40:43,501 --> 00:40:46,000 Well, we get a few turtles, 972 00:40:46,000 --> 00:40:48,999 a few lizards and fish. 973 00:40:49,000 --> 00:40:50,000 You find any dinosaurs 974 00:40:50,001 --> 00:40:51,000 at all above there? 975 00:40:51,001 --> 00:40:52,500 No dinosaurs above 976 00:40:52,501 --> 00:40:53,999 that black line right there. 977 00:40:54,000 --> 00:40:56,000 JOHNSON: 978 00:40:54,000 --> 00:40:57,999 and above is no dinosaurs. 979 00:40:56,001 --> 00:40:58,000 So below is dinosaurs 980 00:40:58,000 --> 00:40:59,000 Absolutely right. 981 00:41:01,000 --> 00:41:03,000 JOHNSON: 982 00:41:01,000 --> 00:41:04,999 above the asteroid impact layer 983 00:41:03,001 --> 00:41:05,000 Nobody has ever found dinosaurs 984 00:41:05,000 --> 00:41:06,500 in North America or anywhere 985 00:41:06,501 --> 00:41:08,000 else on the planet. 986 00:41:11,000 --> 00:41:12,500 To me, that'S 987 00:41:12,501 --> 00:41:13,999 pretty convincing evidence 988 00:41:14,000 --> 00:41:16,000 that this catastrophic collision 989 00:41:16,001 --> 00:41:18,000 wiped out the dinosaurs. 990 00:41:26,000 --> 00:41:28,000 - And they weren'T the only - living things to suffer. 991 00:41:55,000 --> 00:41:57,000 This amazing fossil leaf just 992 00:41:57,001 --> 00:41:58,999 popped out of this rock. 993 00:41:59,000 --> 00:42:00,000 Tap a little bit more, 994 00:42:00,001 --> 00:42:01,001 expose it. 995 00:42:10,000 --> 00:42:12,000 There'S a leaf that hasn'T seen 996 00:42:12,001 --> 00:42:13,999 the sun for 66 million years. 997 00:42:14,000 --> 00:42:15,000 You can even see holes 998 00:42:15,001 --> 00:42:16,000 in the leaf 999 00:42:16,001 --> 00:42:17,500 where cretaceous insects fed 1000 00:42:17,501 --> 00:42:18,999 on the leaf 1001 00:42:19,000 --> 00:42:21,000 when it was growing in a forest 1002 00:42:21,001 --> 00:42:22,999 that was full of dinosaurs. 1003 00:42:23,000 --> 00:42:24,500 And it'S this world 1004 00:42:24,501 --> 00:42:25,999 that was terminated 1005 00:42:26,000 --> 00:42:28,000 by the impact of the asteroid. 1006 00:42:34,000 --> 00:42:35,500 We lost more than half 1007 00:42:35,501 --> 00:42:36,999 the species of plants 1008 00:42:37,000 --> 00:42:38,000 and more than half 1009 00:42:38,001 --> 00:42:39,000 the species of insects. 1010 00:42:39,001 --> 00:42:41,500 It was truly an ecosystem-wide 1011 00:42:41,501 --> 00:42:44,000 devastating event. 1012 00:42:46,000 --> 00:42:48,500 But even with all this global 1013 00:42:48,501 --> 00:42:50,999 destruction, among the survivors 1014 00:42:51,000 --> 00:42:53,000 was one special group of animals 1015 00:42:53,001 --> 00:42:54,999 that managed to hang on: 1016 00:42:55,000 --> 00:42:57,000 The mammals. 1017 00:42:59,000 --> 00:43:00,500 It was little mammals not unlike 1018 00:43:00,501 --> 00:43:01,999 these chipmunks 1019 00:43:02,000 --> 00:43:03,500 that survived the asteroid 1020 00:43:03,501 --> 00:43:04,999 impact, and they survived 1021 00:43:05,000 --> 00:43:06,500 because they had small body 1022 00:43:06,501 --> 00:43:07,999 size, a large population size, 1023 00:43:08,000 --> 00:43:09,500 they could reproduce fast, 1024 00:43:09,501 --> 00:43:10,999 they lived in burrows. 1025 00:43:11,000 --> 00:43:12,500 They were almost pre-adapted 1026 00:43:12,501 --> 00:43:13,999 to survive an event 1027 00:43:14,000 --> 00:43:16,999 like the asteroid impact. 1028 00:43:17,000 --> 00:43:18,000 And once the dinosaurs were gone 1029 00:43:18,001 --> 00:43:19,500 they had the world 1030 00:43:19,501 --> 00:43:21,000 to themselves. 1031 00:43:23,000 --> 00:43:24,500 In the millions of years 1032 00:43:24,501 --> 00:43:25,999 that followed, 1033 00:43:26,000 --> 00:43:28,500 mammals evolved and changed, 1034 00:43:28,501 --> 00:43:30,999 spread and diversified. 1035 00:43:31,000 --> 00:43:35,500 They filled every available 1036 00:43:35,501 --> 00:43:39,999 niche on land, sea, and air 1037 00:43:40,000 --> 00:43:42,000 here in North America 1038 00:43:42,001 --> 00:43:43,999 and all over the planet. 1039 00:43:44,000 --> 00:43:45,500 But it'S the evolution of one 1040 00:43:45,501 --> 00:43:46,999 particular group of mammals, 1041 00:43:47,000 --> 00:43:49,000 the primates, that'S of special 1042 00:43:49,001 --> 00:43:51,000 importance to us. 1043 00:43:53,000 --> 00:43:54,280 But there'S a huge mystery. 1044 00:44:00,000 --> 00:44:01,500 Today, except for some monkeys 1045 00:44:01,501 --> 00:44:02,999 in Central America, 1046 00:44:03,000 --> 00:44:06,500 the only primates native to our 1047 00:44:06,501 --> 00:44:10,000 continent are us: Human beings. 1048 00:44:14,000 --> 00:44:15,000 If you want to see 1049 00:44:15,001 --> 00:44:16,000 other primates, 1050 00:44:16,001 --> 00:44:17,500 like gorillas, baboons, 1051 00:44:17,501 --> 00:44:18,999 and monkeys, 1052 00:44:19,000 --> 00:44:21,000 you have to visit a zoo. 1053 00:44:23,000 --> 00:44:25,999 Or come to a place like this: 1054 00:44:26,000 --> 00:44:28,000 The Duke University. 1055 00:44:28,001 --> 00:44:30,000 Lemur Center. 1056 00:44:35,000 --> 00:44:36,000 Whoa! 1057 00:44:36,001 --> 00:44:38,000 - Look how high - that thing is going. 1058 00:44:40,000 --> 00:44:41,000 It'S an 80-acre site 1059 00:44:41,001 --> 00:44:42,500 dedicated to the study 1060 00:44:42,501 --> 00:44:43,999 and preservation of lemurs, 1061 00:44:44,000 --> 00:44:46,500 a group of primates 1062 00:44:46,501 --> 00:44:49,000 that evolved in Madagascar. 1063 00:44:59,000 --> 00:45:01,000 - Here they come, there'S a bunch - coming at me right now. 1064 00:45:05,000 --> 00:45:06,000 That one'S eating 1065 00:45:06,001 --> 00:45:07,000 one peanut in each hand. 1066 00:45:07,001 --> 00:45:09,000 - It'S like he'S eating - ice cream cones. 1067 00:45:09,003 --> 00:45:11,000 Wow, this is awesome to be 1068 00:45:11,001 --> 00:45:13,000 so close to these things. 1069 00:45:18,000 --> 00:45:19,500 Incredible how well they move 1070 00:45:19,501 --> 00:45:20,999 through the forest 1071 00:45:21,000 --> 00:45:22,000 and to actually see them 1072 00:45:22,001 --> 00:45:23,000 moving around the trees. 1073 00:45:23,001 --> 00:45:25,000 - They'Ll go straight up - a tree 40 feet 1074 00:45:25,003 --> 00:45:26,500 And then jump probably 25, 1075 00:45:26,501 --> 00:45:27,999 30 feet between the trees. 1076 00:45:28,000 --> 00:45:29,500 Seeing these little guys leap 1077 00:45:29,501 --> 00:45:30,999 from tree to tree, 1078 00:45:31,000 --> 00:45:32,500 you quickly realize that almost 1079 00:45:32,501 --> 00:45:33,999 everything about primates 1080 00:45:34,000 --> 00:45:36,500 is perfectly adapted 1081 00:45:36,501 --> 00:45:38,999 to a tree-filled environment. 1082 00:45:39,000 --> 00:45:40,500 And that kind of makes 1083 00:45:40,501 --> 00:45:41,999 you wonder. 1084 00:45:42,000 --> 00:45:43,500 We'Ve got plenty of forests 1085 00:45:43,501 --> 00:45:44,999 here in North America. 1086 00:45:45,000 --> 00:45:47,000 - Why don'T we have primates - like these lemurs 1087 00:45:47,003 --> 00:45:50,000 Jumping through our trees? 1088 00:45:54,000 --> 00:45:55,040 Well, the fact is, we did. 1089 00:45:58,000 --> 00:46:00,000 And paleontologist Doug Boyer 1090 00:46:00,001 --> 00:46:02,000 can show us. 1091 00:46:05,000 --> 00:46:06,999 Ah, that'S a nice one. 1092 00:46:07,000 --> 00:46:08,000 JOHNSON: 1093 00:46:08,001 --> 00:46:09,000 One example is now 1094 00:46:09,001 --> 00:46:12,000 a jumble of bones encased in a 1095 00:46:12,001 --> 00:46:14,999 block of sandstone from Wyoming. 1096 00:46:15,000 --> 00:46:17,000 - This particular accumulation - of bones happens to be 1097 00:46:17,003 --> 00:46:18,999 About 48 million years old. 1098 00:46:19,000 --> 00:46:21,000 - There'S still a lot of rock - on it though. 1099 00:46:21,003 --> 00:46:23,000 Well, instead of extracting 1100 00:46:23,001 --> 00:46:24,999 every bone physically, 1101 00:46:25,000 --> 00:46:27,000 we can scan it. 1102 00:46:40,000 --> 00:46:43,000 JOHNSON: 1103 00:46:40,000 --> 00:46:45,999 a faint image comes into view. 1104 00:46:43,001 --> 00:46:46,000 As the scanner gets to work, 1105 00:46:46,000 --> 00:46:47,500 Now we can see something 1106 00:46:47,501 --> 00:46:48,999 starting to come through. 1107 00:46:49,000 --> 00:46:50,000 - JOHNSON: - Oh, wow, look at that. 1108 00:46:50,003 --> 00:46:51,500 There'S the elbow 1109 00:46:51,501 --> 00:46:53,000 coming into view. 1110 00:46:54,000 --> 00:46:55,000 It'S so tantalizing. 1111 00:46:55,001 --> 00:46:56,500 You just see those... 1112 00:46:56,501 --> 00:46:58,000 there'S sort of shapes in there. 1113 00:47:00,000 --> 00:47:01,000 JOHNSON: - From the scan data, 1114 00:47:01,003 --> 00:47:03,500 Doug builds up 1115 00:47:03,501 --> 00:47:05,999 a full 3-D image of the fossil. 1116 00:47:06,000 --> 00:47:09,999 It reveals an amazing feature. 1117 00:47:10,000 --> 00:47:11,999 We have some of the hand here. 1118 00:47:12,000 --> 00:47:13,000 Here'S some of 1119 00:47:13,001 --> 00:47:14,001 the finger bones. 1120 00:47:16,000 --> 00:47:18,000 - JOHNSON: - How long those fingers are! 1121 00:47:18,003 --> 00:47:19,999 They'Re really long. 1122 00:47:20,000 --> 00:47:22,000 BOYER: 1123 00:47:20,000 --> 00:47:23,999 incredibly long fingers. 1124 00:47:22,001 --> 00:47:24,000 This animal had 1125 00:47:24,000 --> 00:47:26,000 - If we were to scale this animal - up to your size... 1126 00:47:26,003 --> 00:47:27,500 My fingers would be, 1127 00:47:27,501 --> 00:47:28,999 like, that long. 1128 00:47:29,000 --> 00:47:30,999 Freakishly long fingers. 1129 00:47:31,000 --> 00:47:33,000 - You'D have fingers that were - about nine inches long. 1130 00:47:33,001 --> 00:47:34,001 Wow. 1131 00:47:35,000 --> 00:47:37,000 JOHNSON: 1132 00:47:35,000 --> 00:47:38,999 perfect for grasping, 1133 00:47:37,001 --> 00:47:39,000 Those long fingers, 1134 00:47:39,000 --> 00:47:40,000 are a tell-tale sign 1135 00:47:40,001 --> 00:47:41,001 of a primate. 1136 00:47:46,000 --> 00:47:47,500 And thousands of early primate 1137 00:47:47,501 --> 00:47:48,999 specimens have been found 1138 00:47:49,000 --> 00:47:51,000 all over America. 1139 00:48:02,000 --> 00:48:04,000 These little guys were 1140 00:48:04,001 --> 00:48:05,999 about two feet long. 1141 00:48:06,000 --> 00:48:07,500 Like the lemurs, 1142 00:48:07,501 --> 00:48:08,999 they were great tree-climbers 1143 00:48:09,000 --> 00:48:12,000 and probably lived on fruit. 1144 00:48:13,000 --> 00:48:15,000 - When you watch these guys moving - around the forest, 1145 00:48:15,003 --> 00:48:16,500 You realize what all these 1146 00:48:16,501 --> 00:48:17,999 adaptations are for: 1147 00:48:18,000 --> 00:48:21,000 The long fingers, the long toes, 1148 00:48:21,001 --> 00:48:23,999 the tail, the ability to jump. 1149 00:48:24,000 --> 00:48:25,000 When you look at the fossils, 1150 00:48:25,001 --> 00:48:27,000 - it'S the same features - preserved in the bones. 1151 00:48:27,003 --> 00:48:28,500 It doesn'T take 1152 00:48:28,501 --> 00:48:29,999 an expert to realize 1153 00:48:30,000 --> 00:48:31,000 that those fossils belonged 1154 00:48:31,001 --> 00:48:33,000 - to animals that were - like these animals 1155 00:48:33,003 --> 00:48:36,000 And lived and moved in forests. 1156 00:48:39,000 --> 00:48:41,000 So, how did all these 1157 00:48:41,001 --> 00:48:42,999 ancient primates get here? 1158 00:48:43,000 --> 00:48:45,000 Where did they come from? 1159 00:48:49,000 --> 00:48:52,500 56 million years ago, 1160 00:48:52,501 --> 00:48:55,999 a huge, fiery rift opened up 1161 00:48:56,000 --> 00:48:57,000 - in what'S now - the North Atlantic. 1162 00:48:59,000 --> 00:49:00,500 An event with dramatic 1163 00:49:00,501 --> 00:49:01,999 consequences 1164 00:49:02,000 --> 00:49:03,500 for North America 1165 00:49:03,501 --> 00:49:05,000 and our entire planet. 1166 00:49:10,000 --> 00:49:11,500 Volcanic eruptions poured huge 1167 00:49:11,501 --> 00:49:12,999 amounts of lava 1168 00:49:13,000 --> 00:49:15,000 for thousands of years. 1169 00:49:18,000 --> 00:49:20,000 Releasing colossal amounts 1170 00:49:20,001 --> 00:49:21,999 of greenhouse gases, 1171 00:49:22,000 --> 00:49:24,000 like carbon dioxide and methane. 1172 00:49:26,000 --> 00:49:27,500 Like a blanket 1173 00:49:27,501 --> 00:49:28,999 in the atmosphere, 1174 00:49:29,000 --> 00:49:31,000 they kept in the heat, 1175 00:49:31,001 --> 00:49:32,999 leading to an intense period 1176 00:49:33,000 --> 00:49:34,500 of global warming 1177 00:49:34,501 --> 00:49:35,999 that changed the vegetation 1178 00:49:36,000 --> 00:49:38,000 across North America. 1179 00:49:39,000 --> 00:49:41,000 The cool forests 1180 00:49:41,001 --> 00:49:42,999 covering the north 1181 00:49:43,000 --> 00:49:44,500 turned into dense 1182 00:49:44,501 --> 00:49:45,999 subtropical rainforests 1183 00:49:46,000 --> 00:49:47,000 stretching all the way 1184 00:49:47,001 --> 00:49:48,001 to Alaska. 1185 00:49:49,000 --> 00:49:50,500 These trees kept their leaves 1186 00:49:50,501 --> 00:49:51,999 all year round, 1187 00:49:52,000 --> 00:49:54,500 providing food and shelter 1188 00:49:54,501 --> 00:49:56,999 for primates 1189 00:49:57,000 --> 00:49:59,500 so they could make the leap 1190 00:49:59,501 --> 00:50:01,999 from Asia across a land bridge, 1191 00:50:02,000 --> 00:50:03,500 a leafy highway 1192 00:50:03,501 --> 00:50:05,000 to North America. 1193 00:50:07,000 --> 00:50:08,500 They hung around for more 1194 00:50:08,501 --> 00:50:09,999 than 20 million years, 1195 00:50:10,000 --> 00:50:11,000 - spreading all over - our continent. 1196 00:50:15,000 --> 00:50:16,000 But then temperatures 1197 00:50:16,001 --> 00:50:17,000 dropped sharply, 1198 00:50:17,001 --> 00:50:19,000 - wiping out - the subtropical forests 1199 00:50:19,003 --> 00:50:21,000 And their leaping inhabitants. 1200 00:50:23,000 --> 00:50:24,999 For millions of years, 1201 00:50:25,000 --> 00:50:26,500 nearly all of North America 1202 00:50:26,501 --> 00:50:28,000 would remain primate-free. 1203 00:50:31,000 --> 00:50:34,999 Then, around 14,000 years ago, 1204 00:50:35,000 --> 00:50:36,500 almost a blink 1205 00:50:36,501 --> 00:50:37,999 in geological time, 1206 00:50:38,000 --> 00:50:39,500 a certain two-legged primate 1207 00:50:39,501 --> 00:50:41,000 made its entrance. 1208 00:50:42,000 --> 00:50:44,999 That primate, of course, was us, 1209 00:50:45,000 --> 00:50:47,500 and our arrival changed 1210 00:50:47,501 --> 00:50:50,000 everything. 1211 00:50:52,000 --> 00:50:54,000 - The first humans to arrive - in America 1212 00:50:54,003 --> 00:50:56,500 Found a land full 1213 00:50:56,501 --> 00:50:58,999 of untold riches. 1214 00:50:59,000 --> 00:51:01,000 - They'D really have a whole new - world open in front of them. 1215 00:51:01,003 --> 00:51:02,500 They could move down the coast, 1216 00:51:02,501 --> 00:51:03,999 which was full of resources: 1217 00:51:04,000 --> 00:51:10,999 Fish, whales, seals, deer. 1218 00:51:11,000 --> 00:51:13,000 And the coastline is like 1219 00:51:13,001 --> 00:51:14,999 an open pathway, a gateway 1220 00:51:15,000 --> 00:51:17,500 into a continent four billion 1221 00:51:17,501 --> 00:51:20,000 years in the making... 1222 00:51:22,000 --> 00:51:24,000 providing us with an enormous 1223 00:51:24,001 --> 00:51:26,000 geological bounty. 1224 00:51:27,000 --> 00:51:28,500 Gifts of the earth hidden 1225 00:51:28,501 --> 00:51:29,999 in the landscape... 1226 00:51:30,000 --> 00:51:36,999 gold, iron, oil, and more... 1227 00:51:37,000 --> 00:51:38,500 harnessed to build 1228 00:51:38,501 --> 00:51:39,999 the vast civilization 1229 00:51:40,000 --> 00:51:42,999 that surrounds us today. 1230 00:51:43,000 --> 00:51:44,000 For the first time 1231 00:51:44,001 --> 00:51:45,500 in the history of life 1232 00:51:45,501 --> 00:51:46,999 in North America, 1233 00:51:47,000 --> 00:51:49,000 here was a species that would 1234 00:51:49,001 --> 00:51:50,999 not just adapt to the landscape, 1235 00:51:51,000 --> 00:51:54,000 but transform it. 1236 00:52:22,000 --> 00:52:24,000 - The three-partiNOVAoseriess - "Making North America" 1237 00:52:24,003 --> 00:52:25,999 Is available on DVD. 1238 00:52:26,000 --> 00:52:28,500 To order, visit shoppbs.org 1239 00:52:28,501 --> 00:52:30,999 or call 1-800-PLAY-PBS. 1240 00:52:31,000 --> 00:52:32,500 NOVA is also available 1241 00:52:32,501 --> 00:52:34,000 for download from iTunes.