1 00:00:16,517 --> 00:00:21,563 Surely, one of the most remarkable animals that has ever existed, 2 00:00:22,105 --> 00:00:26,318 and certainly one of the most famous, is a dinosaur. 3 00:00:27,361 --> 00:00:29,613 Tyrannosaurus rex. 4 00:00:30,656 --> 00:00:35,202 An animal to spark the imagination for all of us. 5 00:00:35,285 --> 00:00:38,247 What kind of an animal was it? 6 00:00:38,330 --> 00:00:41,542 What did it look like? How did it live? 7 00:00:41,625 --> 00:00:45,587 Now, scientific research has answered such questions. 8 00:00:45,671 --> 00:00:47,923 And not just about T. rex, 9 00:00:48,006 --> 00:00:51,343 but the other species that lived alongside it. 10 00:00:51,426 --> 00:00:58,016 And the latest imaging technology enables us to bring them all to life. 11 00:01:01,436 --> 00:01:05,440 Planet Earth, 66 million years ago. 12 00:01:13,949 --> 00:01:17,494 The skies are filled with flying giants. 13 00:01:20,038 --> 00:01:24,084 In the seas, monstrous reptiles patrol the depths. 14 00:01:26,128 --> 00:01:29,256 And on land, dinosaurs of every kind, 15 00:01:30,465 --> 00:01:33,218 all facing the struggle to survive. 16 00:01:39,391 --> 00:01:45,689 We now know so much about a world that was ruled by the dinosaurs. 17 00:01:49,651 --> 00:01:52,196 This is their story. 18 00:02:14,468 --> 00:02:20,224 The forests in South America contain some of the world's tallest trees. 19 00:02:24,603 --> 00:02:28,023 They can grow to a height of over 300 feet. 20 00:02:33,570 --> 00:02:36,573 But there are animal giants here too. 21 00:03:01,098 --> 00:03:03,433 Plant-eating dinosaurs. 22 00:03:11,108 --> 00:03:13,694 These are Austroposeidon. 23 00:03:14,278 --> 00:03:16,738 They're 80 feet long. 24 00:03:27,499 --> 00:03:30,043 And they have colossal appetites. 25 00:03:32,838 --> 00:03:36,758 Their teeth are used not to chew, 26 00:03:37,342 --> 00:03:39,011 but simply to cut. 27 00:03:44,349 --> 00:03:50,314 A herd like this one can consume ten tons of vegetation every day. 28 00:03:55,402 --> 00:04:01,033 They prefer the tender, young leaves that grow on the tips of the branches. 29 00:04:03,035 --> 00:04:06,872 But if they find trees that are even taller than they are, 30 00:04:06,955 --> 00:04:08,498 they're not defeated. 31 00:04:21,386 --> 00:04:25,933 They use their great weight and their 8-inch-thick breastbone 32 00:04:26,016 --> 00:04:29,144 to simply push the trees over. 33 00:05:03,095 --> 00:05:04,263 Success. 34 00:05:07,432 --> 00:05:10,477 But life in the forest is always a battle. 35 00:05:12,271 --> 00:05:15,399 Especially when new space is created. 36 00:05:33,333 --> 00:05:36,211 Plants race to claim the light… 37 00:05:38,255 --> 00:05:42,467 and use every kind of method to gain the upper hand. 38 00:05:51,852 --> 00:05:55,063 The gap in the canopy is soon closed. 39 00:06:01,153 --> 00:06:05,782 Over three-quarters of the world's land is covered by plants and trees. 40 00:06:09,870 --> 00:06:13,832 This prehistoric planet is a green planet. 41 00:06:18,086 --> 00:06:21,882 Many different species of dinosaur live in forests. 42 00:06:25,052 --> 00:06:29,890 Triceratops, one of the biggest in North America. 43 00:06:35,646 --> 00:06:38,065 They can be 26 feet long. 44 00:06:43,111 --> 00:06:47,866 The huge frills on their heads are used for protection when they fight. 45 00:06:52,246 --> 00:06:54,665 But plants have defenses too. 46 00:07:00,337 --> 00:07:02,005 Poisonous toxins. 47 00:07:09,721 --> 00:07:12,724 These are particularly dangerous for youngsters. 48 00:07:15,936 --> 00:07:20,774 This calf weighs only a 50th of the weight of his mother. 49 00:07:23,861 --> 00:07:28,198 And the plant's toxins could make him very sick indeed. 50 00:07:38,959 --> 00:07:43,088 But Triceratops have a way of dealing with such poisons. 51 00:07:44,965 --> 00:07:47,092 They use an antidote. 52 00:07:54,057 --> 00:07:59,104 One source of it lies in a cave to which they pay regular visits. 53 00:08:14,786 --> 00:08:19,124 This youngster, however, has never been in here before. 54 00:08:41,897 --> 00:08:44,232 They have to find their way along a passage 55 00:08:44,316 --> 00:08:49,363 that, over many millennia, has been eroded by an underground river. 56 00:09:09,800 --> 00:09:13,178 They are now beyond the reach of light. 57 00:09:15,806 --> 00:09:17,641 They can't see a thing. 58 00:09:23,146 --> 00:09:25,983 The calf must stick close to his family. 59 00:09:34,741 --> 00:09:36,243 But not too close. 60 00:09:56,889 --> 00:10:01,101 Now, one wrong turn could be disastrous. 61 00:10:40,432 --> 00:10:44,394 At last, the herd reaches the place they need to visit. 62 00:10:54,821 --> 00:10:59,535 This is the antidote: a special clay. 63 00:11:02,621 --> 00:11:07,751 These are known as clay licks, and they're visited time and again. 64 00:11:28,188 --> 00:11:30,190 But someone is missing. 65 00:11:36,613 --> 00:11:38,240 Where is her calf? 66 00:12:06,351 --> 00:12:08,729 Luck was on the youngster's side. 67 00:12:24,786 --> 00:12:27,331 Once he's lined his stomach with clay, 68 00:12:27,414 --> 00:12:32,503 he too will be protected from the poisons in the leaves on which he feeds. 69 00:12:37,508 --> 00:12:42,054 Soon they will all head back to the forest and daylight. 70 00:12:47,309 --> 00:12:50,354 In fact, very little of the sun's light 71 00:12:50,437 --> 00:12:53,524 reaches the floor of these dense forests. 72 00:12:55,567 --> 00:12:56,693 In Patagonia, 73 00:12:56,777 --> 00:13:01,156 the thick vegetation stretches unbroken for hundreds of miles. 74 00:13:04,701 --> 00:13:09,414 But occasionally, there are mysterious clearings, like this one. 75 00:13:28,475 --> 00:13:35,023 It's the work of a two-ton, 12-foot tall Carnotaurus. A male. 76 00:13:39,862 --> 00:13:43,574 Clearing this patch has taken him a long time. 77 00:13:46,285 --> 00:13:50,372 And it needs constant attention if it is to remain tidy. 78 00:13:58,005 --> 00:14:01,884 It's a stage on which he can show off to females. 79 00:14:05,220 --> 00:14:08,807 All is ready, and he announces the fact. 80 00:14:22,321 --> 00:14:24,156 His calls are low-pitched 81 00:14:24,239 --> 00:14:27,284 and travel much farther through the dense vegetation 82 00:14:27,367 --> 00:14:29,494 than higher-pitched ones would do. 83 00:14:53,143 --> 00:14:56,230 At last, a female arrives. 84 00:15:04,196 --> 00:15:07,824 She's bigger than the male and more powerful. 85 00:15:22,214 --> 00:15:25,509 Now, somehow, he must impress her. 86 00:15:30,305 --> 00:15:33,016 And he may only get this one chance. 87 00:15:36,645 --> 00:15:38,689 She watches him carefully. 88 00:15:42,901 --> 00:15:44,778 If he is going to impress her, 89 00:15:45,529 --> 00:15:49,032 he must do so in the most extraordinary way. 90 00:15:59,710 --> 00:16:03,881 He doesn't have huge antlers, nor a spectacular tail. 91 00:16:06,216 --> 00:16:11,263 But he does have a pair of tiny, apparently useless arms. 92 00:16:15,434 --> 00:16:18,812 And each has a ball and socket joint at its base 93 00:16:18,896 --> 00:16:22,566 that enables him to move them independently. 94 00:16:51,595 --> 00:16:52,721 Not today. 95 00:17:00,020 --> 00:17:03,398 How could he have done better? Who knows? 96 00:17:08,694 --> 00:17:12,366 For now, it's back to litter picking. 97 00:17:20,582 --> 00:17:23,001 This is East Asia. 98 00:17:27,422 --> 00:17:31,677 In these mountain forests, autumn arrives early. 99 00:17:37,516 --> 00:17:40,853 This is when many trees produce their fruit. 100 00:17:44,857 --> 00:17:49,987 And amongst the most highly prized are the nuts of the Ginkgo tree. 101 00:17:56,952 --> 00:18:01,498 A bonanza for dinosaurs called Corythoraptors. 102 00:18:06,211 --> 00:18:09,256 Although they have feathers, they're flightless. 103 00:18:13,552 --> 00:18:17,389 These have found a particularly abundant fall of fruit. 104 00:18:18,974 --> 00:18:22,978 But such gatherings can attract unwelcome attention. 105 00:18:28,358 --> 00:18:33,447 Qianzhousaurus, the top predator in these Asiatic forests. 106 00:18:40,829 --> 00:18:43,832 This is a female, over 30 feet long. 107 00:18:48,587 --> 00:18:53,091 If she is to catch a Corythoraptor, she'll have to get close. 108 00:19:01,183 --> 00:19:03,143 There's not much cover here. 109 00:19:08,232 --> 00:19:12,361 But her prey have still not noticed her. 110 00:20:02,494 --> 00:20:04,037 She has failed. 111 00:20:04,121 --> 00:20:05,873 But then, most hunts, 112 00:20:05,956 --> 00:20:10,252 throughout the history of life, fail most of the time. 113 00:20:18,343 --> 00:20:20,596 As the seasonal winds strengthen, 114 00:20:20,679 --> 00:20:25,726 many of the trees in these temperate forests start to lose their leaves. 115 00:20:29,688 --> 00:20:32,274 Winter will be a time of hardship. 116 00:20:38,155 --> 00:20:43,160 Nevertheless, a storm does create a brief opportunity for hunters. 117 00:20:45,746 --> 00:20:47,247 She's trying again. 118 00:20:51,710 --> 00:20:57,341 She's less conspicuous in the gloom, and the gusting wind is distracting. 119 00:21:48,642 --> 00:21:50,811 An 80-pound prize. 120 00:21:53,981 --> 00:21:57,985 All the more valuable, since winter is now closing in. 121 00:22:06,618 --> 00:22:08,662 In the forests of North America, 122 00:22:09,246 --> 00:22:14,626 there is an additional annual hazard for forest dwellers. 123 00:22:24,928 --> 00:22:28,974 Fire, started by a strike of lightning. 124 00:22:38,150 --> 00:22:43,363 As it spreads, temperatures rise to over 2,000 degrees Fahrenheit. 125 00:22:57,628 --> 00:23:01,048 The flames rise several hundred feet into the air. 126 00:23:16,146 --> 00:23:17,814 Most animals flee. 127 00:23:19,942 --> 00:23:24,154 But this Edmontosaurus has a family to care for. 128 00:23:26,573 --> 00:23:28,242 She doesn't abandon them. 129 00:23:30,327 --> 00:23:35,791 Now they must keep one step ahead of the blaze until it burns out. 130 00:23:47,302 --> 00:23:50,264 This may look catastrophic. 131 00:23:57,312 --> 00:24:01,316 But remarkably, some plants must be burnt 132 00:24:01,400 --> 00:24:04,027 if they are to complete their life cycle. 133 00:24:08,240 --> 00:24:12,911 The intense heat is needed to open the cones of the pine trees… 134 00:24:15,372 --> 00:24:17,249 and release their seeds. 135 00:24:28,260 --> 00:24:31,597 And only a few hours after the fire has passed, 136 00:24:33,348 --> 00:24:36,101 animals begin to return. 137 00:24:39,980 --> 00:24:42,316 Beetles are among the first. 138 00:24:45,736 --> 00:24:47,696 They start to lay their eggs. 139 00:24:49,156 --> 00:24:52,618 When they hatch, the larvae will be the first to feast 140 00:24:52,701 --> 00:24:56,121 on the near-limitless supply of dead wood. 141 00:25:06,757 --> 00:25:10,260 This Atrociraptor is an opportunist. 142 00:25:18,227 --> 00:25:21,939 Quick to return when there's food on offer. 143 00:25:27,152 --> 00:25:29,530 And there's something else to be gained here. 144 00:25:40,332 --> 00:25:42,960 Smoke is an insecticide… 145 00:25:47,214 --> 00:25:51,218 and it can help an animal to get rid of its parasites. 146 00:25:57,224 --> 00:25:59,351 But you do have to be careful. 147 00:26:15,450 --> 00:26:18,537 A two-ton ankylosaur. 148 00:26:23,083 --> 00:26:26,920 It also finds something worth eating after a fire. 149 00:26:36,096 --> 00:26:37,181 Charcoal. 150 00:26:39,766 --> 00:26:45,230 It will bind with many of the plant toxins in its stomach and neutralize them. 151 00:26:57,242 --> 00:27:01,246 The female Edmontosaurus is leaving the forest. 152 00:27:08,337 --> 00:27:12,716 Against the odds, she's led both her babies to safety. 153 00:27:27,189 --> 00:27:32,486 They will have to find new pastures until the forest plants recover. 154 00:27:42,329 --> 00:27:46,750 Even where fires are rare, trees do not live forever. 155 00:27:47,292 --> 00:27:52,422 And after they die, they become food for a very different kind of organism. 156 00:27:57,636 --> 00:28:02,057 At night, some of them become eerily conspicuous. 157 00:28:05,936 --> 00:28:08,313 Down on the forest floor… 158 00:28:11,525 --> 00:28:13,527 fungi appear… 159 00:28:15,487 --> 00:28:17,739 and start to glow. 160 00:28:25,831 --> 00:28:30,919 They produce their light by chemical reactions deep within their tissues. 161 00:28:35,048 --> 00:28:37,968 But why they do so is a mystery. 162 00:28:41,597 --> 00:28:44,266 It may be because the light attracts insects, 163 00:28:44,349 --> 00:28:47,728 which then help to spread the spores of the fungus. 164 00:28:56,236 --> 00:28:58,322 Here, in central Asia, 165 00:28:58,405 --> 00:29:03,076 the nighttime forest is filled with strange sounds. 166 00:29:09,791 --> 00:29:12,753 Giant sauropods are asleep. 167 00:29:19,259 --> 00:29:22,054 There are air sacs in their head and neck, 168 00:29:22,137 --> 00:29:26,350 which reduce their weight but also amplify their snores. 169 00:29:30,979 --> 00:29:33,398 But not everyone is asleep. 170 00:29:37,569 --> 00:29:42,783 For smaller creatures, it's safer to be out in the darkness than during the day. 171 00:29:45,661 --> 00:29:50,791 These Therizinosaurus hatched just six months ago. 172 00:29:55,879 --> 00:30:00,634 Barely three feet long, they are only a tenth of their adult size. 173 00:30:03,387 --> 00:30:08,892 Their claws may look like daggers, but they're used more like salad servers… 174 00:30:12,521 --> 00:30:15,315 because these are plant eaters. 175 00:30:18,151 --> 00:30:23,907 This forest, however, has all kinds of food if you know where to look. 176 00:30:26,076 --> 00:30:27,077 Honey. 177 00:30:29,371 --> 00:30:33,125 It's dripping from a bees' nest up in the branches. 178 00:30:36,837 --> 00:30:41,091 Bees usually build their nests beyond the reach of ground dwellers. 179 00:30:42,801 --> 00:30:45,262 But this one is lower than most. 180 00:30:47,764 --> 00:30:49,766 And it's too good to miss. 181 00:31:08,410 --> 00:31:13,790 Unlike most dinosaurs, young Therizinosaurus can climb. 182 00:31:19,004 --> 00:31:21,798 Although they're not exactly experts. 183 00:31:55,791 --> 00:32:01,839 Angry bees produce a Mexican wave to warn intruders to keep away… 184 00:32:08,387 --> 00:32:10,222 or suffer the consequences. 185 00:32:39,543 --> 00:32:42,254 An adult Therizinosaurus. 186 00:32:47,634 --> 00:32:53,098 It's huge, nearly 30 feet tall and weighing five tons. 187 00:33:13,118 --> 00:33:16,496 Nothing the bees can do deters this one. 188 00:33:35,015 --> 00:33:37,476 At last, a little treat. 189 00:33:39,478 --> 00:33:42,564 And a few more stings. 190 00:33:57,871 --> 00:34:03,126 Even by day, it's still dark in the understory of the dense forests, 191 00:34:03,210 --> 00:34:05,546 such as this one in Europe. 192 00:34:09,174 --> 00:34:12,844 Animals of any kind are difficult to distinguish. 193 00:34:18,934 --> 00:34:20,811 Yet, they're everywhere. 194 00:34:26,233 --> 00:34:29,485 Telmatosaurus seldom breaks cover. 195 00:34:39,413 --> 00:34:42,123 And equally inconspicuous… 196 00:34:46,043 --> 00:34:47,420 Zalmoxes. 197 00:34:49,965 --> 00:34:53,302 The last of a very ancient dinosaur lineage. 198 00:34:56,929 --> 00:35:00,809 This forest is one of their few remaining strongholds. 199 00:35:04,771 --> 00:35:10,777 Seven inches tall, baby Zalmoxes are no more than snacks for many predators. 200 00:35:11,695 --> 00:35:14,740 But snacks are nonetheless worth eating… 201 00:35:16,533 --> 00:35:18,327 so they have to be cautious. 202 00:35:48,524 --> 00:35:52,694 Hatzegopteryx stands 15 feet tall. 203 00:36:03,247 --> 00:36:07,918 It is, in fact, a pterosaur, a reptile with wings, 204 00:36:08,001 --> 00:36:12,965 that here, as it stalks through the trees, it has to keep tightly folded. 205 00:36:25,227 --> 00:36:30,858 This forest, so rich in small creatures, is one of its regular hunting grounds. 206 00:36:38,991 --> 00:36:42,035 It stands on the southernmost edge of Europe. 207 00:37:09,521 --> 00:37:12,691 This is the heaviest animal ever to fly, 208 00:37:12,774 --> 00:37:17,738 and there is nowhere else here where it can open its gigantic wings, 209 00:37:17,821 --> 00:37:20,199 which are over 30 feet across. 210 00:37:29,583 --> 00:37:34,296 Many of the forest's permanent residents regularly come down here… 211 00:37:37,841 --> 00:37:40,928 because the plants are coated with sea spray 212 00:37:41,762 --> 00:37:44,681 and are a welcome source of salt. 213 00:38:10,707 --> 00:38:15,754 Here, sauropods can meet one another, renewing family bonds… 214 00:38:18,632 --> 00:38:20,634 and creating new ones. 215 00:38:34,565 --> 00:38:38,485 But for Hatzegopteryx, the beach is a launching pad. 216 00:38:54,001 --> 00:38:57,754 Now his wings will carry him to yet another forest, 217 00:38:57,838 --> 00:39:02,509 where life proliferates more variously and more abundantly 218 00:39:02,593 --> 00:39:07,181 than anywhere else on our prehistoric planet. 219 00:39:22,112 --> 00:39:25,115 To discover the science behind the stories, 220 00:39:25,199 --> 00:39:29,995 go now to the Prehistoric Planet show page.