1 00:00:39,287 --> 00:00:41,198 ATTENBOROUGH: For millions of years 2 00:00:41,287 --> 00:00:45,724 before birds evolved and long before the rise of the mammals 3 00:00:45,807 --> 00:00:49,197 cold-blooded animals ruled the world. 4 00:00:51,887 --> 00:00:54,162 In some places they still do. 5 00:01:00,527 --> 00:01:05,203 Some of these reptiles witnessed the dinosaurs come and go. 6 00:01:11,287 --> 00:01:13,278 Yet in all that time 7 00:01:13,367 --> 00:01:17,076 they themselves remained virtually unchanged. 8 00:01:21,407 --> 00:01:26,083 Among them were some of the most impressive reptiles alive today. 9 00:01:26,527 --> 00:01:29,678 They took that most characteristic of reptilian features 10 00:01:29,767 --> 00:01:34,477 the scale to extremes. They turned it into armour. 11 00:01:36,767 --> 00:01:39,725 That increased their weight but nevertheless 12 00:01:39,807 --> 00:01:42,765 some can still move with extraordinary speed. 13 00:01:48,407 --> 00:01:51,922 And although they may appear cold and impassive 14 00:01:52,007 --> 00:01:55,397 they can nonetheless be passionate 15 00:01:56,287 --> 00:01:58,721 and even affectionate. 16 00:02:02,087 --> 00:02:03,998 (CHIRPING) 17 00:02:04,887 --> 00:02:08,482 Among them are the biggest of all reptiles alive today. 18 00:02:09,007 --> 00:02:12,682 Theyre the crocodiles the turtles and the tortoises. 19 00:02:20,767 --> 00:02:24,203 This is a giant Galapagos tortoise 20 00:02:24,407 --> 00:02:28,958 and its climbed all the way up the flank of this great volcano 21 00:02:29,047 --> 00:02:32,676 and is here wandering around the rim of the crater. 22 00:02:33,167 --> 00:02:37,080 But why should it come to such a bleak and inhospitable place? 23 00:02:40,727 --> 00:02:42,797 Tortoises being reptiles 24 00:02:42,887 --> 00:02:46,880 cant generate their own body heat internally as we do. 25 00:02:46,967 --> 00:02:50,437 Instead they must get it from their surroundings 26 00:02:50,527 --> 00:02:52,802 and these particular ones have come up here 27 00:02:52,887 --> 00:02:56,357 to warm themselves on the hot volcanic rocks 28 00:02:56,447 --> 00:02:58,961 among the jets of steam and sulphurous gas. 29 00:03:01,367 --> 00:03:04,518 They live longer than any other animal on Earth 30 00:03:04,607 --> 00:03:07,121 well over 1 20 years. 31 00:03:10,127 --> 00:03:15,076 They weigh up to a quarter of a tonne and have shells over a metre across. 32 00:03:15,327 --> 00:03:17,318 They really are giants. 33 00:03:22,647 --> 00:03:24,683 (GRUNTING) 34 00:03:25,687 --> 00:03:30,317 Having your body encased in shell obviously brings problems 35 00:03:30,407 --> 00:03:33,285 and one of them is how do you mate? 36 00:03:33,367 --> 00:03:36,598 Making love in a suit of armour is not easy. 37 00:03:38,087 --> 00:03:41,602 But the males have a very ingenious solution. 38 00:03:47,207 --> 00:03:49,846 The underside of their shell is concave 39 00:03:49,927 --> 00:03:54,159 so it fits neatly over the domed top of the shell of the female 40 00:03:54,247 --> 00:03:55,919 who is somewhat smaller. 41 00:03:57,367 --> 00:04:01,519 That doesnt make clambering on top of her any easier initially 42 00:04:01,607 --> 00:04:03,086 but once the male is up there 43 00:04:03,167 --> 00:04:06,239 it will reduce his chance of slipping off. 44 00:04:10,527 --> 00:04:11,880 (GRUNTING) 45 00:04:20,487 --> 00:04:25,083 The two shells fit together as neatly as two spoons. 46 00:04:29,287 --> 00:04:31,596 So mating can begin. 47 00:04:31,687 --> 00:04:35,839 And once started it can go on for a long time. 48 00:04:41,527 --> 00:04:44,644 A tortoises shell is so familiar to us 49 00:04:44,727 --> 00:04:46,285 its easy to forget 50 00:04:46,367 --> 00:04:49,040 what an extraordinary construction it is. 51 00:04:49,927 --> 00:04:51,918 But how did it originate? 52 00:04:52,567 --> 00:04:55,525 Nearly all reptiles are covered in scales 53 00:04:55,607 --> 00:04:58,201 and so were the tortoises ancestors. 54 00:04:59,287 --> 00:05:04,281 But then as they evolved a radical change took place. 55 00:05:06,247 --> 00:05:08,397 The ribs expanded outwards 56 00:05:08,487 --> 00:05:11,877 so that they enclosed the hip and the shoulder joints. 57 00:05:14,927 --> 00:05:18,966 They enlarged and fused with other bones beneath the skin. 58 00:05:20,327 --> 00:05:25,276 They widened and eventually they joined together to form a bony box. 59 00:05:28,567 --> 00:05:33,436 Above the scales in the skin enlarged to form a continuous shield of horn 60 00:05:33,527 --> 00:05:35,677 on the surface of the box. 61 00:05:35,807 --> 00:05:38,241 And the basic armour was complete. 62 00:05:42,407 --> 00:05:46,878 By developing a shell tortoises inevitably sacrifice speed 63 00:05:46,967 --> 00:05:49,686 so they cant sprint off and take shelter 64 00:05:49,767 --> 00:05:51,485 in a crack when danger threatens. 65 00:05:51,567 --> 00:05:55,606 But with a shell like that they seldom need to. 66 00:05:59,447 --> 00:06:03,520 Some have added deluxe features to the basic model. 67 00:06:04,767 --> 00:06:07,327 This is an eastern box turtle. 68 00:06:16,407 --> 00:06:21,242 In North America where it lives there are plenty of would-be predators. 69 00:06:22,727 --> 00:06:24,285 Racoons among them. 70 00:06:24,367 --> 00:06:25,402 (RACOON CHATTERING) 71 00:06:25,487 --> 00:06:27,398 And they have very nimble paws. 72 00:06:27,487 --> 00:06:28,840 (SNIFFING) 73 00:06:35,287 --> 00:06:37,721 But these turtles dont have to worry 74 00:06:37,807 --> 00:06:41,243 because their shell has a special safety feature. 75 00:06:42,607 --> 00:06:44,120 It has a drawbridge. 76 00:06:44,207 --> 00:06:45,845 And when danger threatens 77 00:06:45,927 --> 00:06:49,920 the box turtle just retreats into its shell and pulls it up. 78 00:07:00,007 --> 00:07:02,043 The drawbridge fits so tightly 79 00:07:02,127 --> 00:07:05,642 there is no crack for the racoon to get its teeth into. 80 00:07:21,047 --> 00:07:24,278 After a while most raccoons give up. 81 00:07:29,407 --> 00:07:32,160 Of course when your head is inside your shell 82 00:07:32,247 --> 00:07:35,557 you cant see whether your attacker has gone or not. 83 00:07:35,687 --> 00:07:38,838 So its best to check before you emerge fully. 84 00:07:44,647 --> 00:07:47,844 A shell is an excellent defence against predators 85 00:07:48,207 --> 00:07:50,767 but there are other dangers against which it provides 86 00:07:50,847 --> 00:07:52,565 no protection whatever. 87 00:07:56,207 --> 00:08:00,439 Its midsummer its nearly midday and its very very hot. 88 00:08:01,127 --> 00:08:03,595 And as a consequence Im sweating. 89 00:08:04,127 --> 00:08:09,884 Sweating is a direct response to heat that only mammals can do. 90 00:08:10,567 --> 00:08:14,480 No reptile like this gopher tortoise has got sweat glands 91 00:08:14,567 --> 00:08:18,446 but instead its got another way of keeping itself cool. 92 00:08:21,167 --> 00:08:24,603 Most reptiles head for the shade when it gets too hot. 93 00:08:25,207 --> 00:08:28,916 To see where this gopher tortoise is heading here in Florida 94 00:08:29,007 --> 00:08:31,043 Im going to use this. 95 00:08:32,327 --> 00:08:37,242 A remotely controlled mini-camera on wheels with its own lights. 96 00:08:38,127 --> 00:08:40,561 It can go pretty well anywhere. 97 00:08:42,167 --> 00:08:44,920 The gopher tortoise is heading for home. 98 00:08:50,367 --> 00:08:54,406 And with luck Ill be able to follow it the tortoise 99 00:08:54,487 --> 00:08:58,400 as it goes down into its burrow. 100 00:08:59,927 --> 00:09:03,966 And that camera has also got a thermometer mounted on it. 101 00:09:04,567 --> 00:09:08,685 Already I can see the temperature is beginning to drop. 102 00:09:11,087 --> 00:09:14,682 The further down the burrow we go the cooler it gets. 103 00:09:15,847 --> 00:09:17,883 Now wheres the tortoise? 104 00:09:20,447 --> 00:09:21,846 There it is. 105 00:09:23,367 --> 00:09:24,766 Im right behind. 106 00:09:24,847 --> 00:09:26,200 (CHUCKLING) 107 00:09:28,007 --> 00:09:30,123 Were now a couple of metres in 108 00:09:30,207 --> 00:09:33,882 but the burrow could go on for some 20 feet 1 7 metres. 109 00:09:34,687 --> 00:09:37,679 And its all been built by this tortoise. 110 00:09:43,207 --> 00:09:47,200 (CHUCKLING) Well that is not a tortoise 111 00:09:47,287 --> 00:09:49,482 thats a rattlesnake. 112 00:09:52,127 --> 00:09:55,881 Obviously taking shelter from the heat just as the tortoise is. 113 00:10:00,167 --> 00:10:04,206 The tortoise is so well armoured its in no danger from the snake. 114 00:10:04,287 --> 00:10:08,121 And gopher tortoises dont seem to mind sharing their burrows. 115 00:10:11,367 --> 00:10:12,720 (CHUCKLING) 116 00:10:13,607 --> 00:10:15,916 Its changed its mind and theres its rattle. 117 00:10:19,967 --> 00:10:23,755 Over 1 00 different species of animal have been recorded 118 00:10:23,847 --> 00:10:26,725 taking shelter inside tortoises tunnels. 119 00:10:26,807 --> 00:10:29,367 In fact some can live nowhere else. 120 00:10:29,807 --> 00:10:34,597 But theres another reason why tortoises homes are so popular. 121 00:10:36,807 --> 00:10:39,446 Tortoises are one of the few animals here 122 00:10:39,527 --> 00:10:41,324 that can actually dig. 123 00:10:43,967 --> 00:10:47,198 Each may have more than one burrow within its territory 124 00:10:47,327 --> 00:10:48,601 and thats very valuable 125 00:10:48,687 --> 00:10:52,760 because they have to deal with an even greater danger than sunstroke. 126 00:10:57,967 --> 00:10:59,480 Bush fires. 127 00:11:05,247 --> 00:11:09,957 These are a major and recurrent threat to all the animals that live here. 128 00:11:24,047 --> 00:11:28,643 Tortoise tunnels are invaluable places in which to take refuge. 129 00:11:41,047 --> 00:11:44,596 Gopher tortoises may seem to be unassuming creatures 130 00:11:44,687 --> 00:11:47,440 but their engineering skills are essential 131 00:11:47,527 --> 00:11:50,166 for the survival of the whole ecosystem. 132 00:11:57,767 --> 00:12:01,442 The ground is still smoking but the flames have passed 133 00:12:01,527 --> 00:12:03,563 and the emergency is over. 134 00:12:07,887 --> 00:12:12,722 So by digging tunnels tortoises save not only their lives 135 00:12:12,807 --> 00:12:15,640 but the lives of hundreds of other animals. 136 00:12:16,527 --> 00:12:18,643 But tunnels arent the only place 137 00:12:18,727 --> 00:12:21,685 where you can escape extremes of temperature. 138 00:12:21,767 --> 00:12:25,362 Theres another environment thats cooler and even more stable. 139 00:12:26,327 --> 00:12:27,521 Water. 140 00:12:32,447 --> 00:12:36,599 Some of the ancestral tortoises started to spend all their time there 141 00:12:38,087 --> 00:12:39,884 and became turtles. 142 00:12:47,007 --> 00:12:50,920 Some still walk slowly along the bottom in much the same way 143 00:12:51,007 --> 00:12:53,157 as their ancestors walked on land. 144 00:12:56,047 --> 00:12:59,926 Water is a good place for a cold-blooded animal to live. 145 00:13:00,007 --> 00:13:02,077 It retains its warmth through the night 146 00:13:02,167 --> 00:13:05,204 and stays comfortably cool during the heat of the day. 147 00:13:05,287 --> 00:13:08,165 So turtles are able to keep their body temperature 148 00:13:08,247 --> 00:13:11,125 relatively constant without much difficulty. 149 00:13:25,007 --> 00:13:28,158 Many have developed webs between their toes 150 00:13:28,247 --> 00:13:31,000 and have become very efficient swimmers. 151 00:13:37,847 --> 00:13:40,805 The most aquatic of all freshwater turtles 152 00:13:40,887 --> 00:13:42,240 is found in New Guinea 153 00:13:42,327 --> 00:13:45,683 and a few rivers like this one in northern Australia. 154 00:13:48,367 --> 00:13:50,278 The pig-nosed turtle. 155 00:13:53,727 --> 00:13:57,515 Its feet have become completely transformed into flippers 156 00:13:57,607 --> 00:14:00,440 and are of little use on land. 157 00:14:01,247 --> 00:14:05,035 And indeed the pig-nosed turtle rarely comes ashore. 158 00:14:09,527 --> 00:14:12,883 But turtles are descended from land-living ancestors 159 00:14:12,967 --> 00:14:15,401 and so they still need to breathe air. 160 00:14:25,327 --> 00:14:30,196 Females also have to return to land in order to lay their eggs. 161 00:14:32,207 --> 00:14:36,519 Pig-noses nest during the dry season high up on the river bank. 162 00:14:39,887 --> 00:14:43,926 If turtle eggs get wet the babies inside them will drown. 163 00:14:44,007 --> 00:14:47,522 At least that is the case with most turtles. 164 00:14:49,407 --> 00:14:53,366 An egg for a turtle represents a huge investment 165 00:14:53,447 --> 00:14:55,517 as it does for any reptile. 166 00:14:56,047 --> 00:14:58,845 So turtles go to a great deal of trouble 167 00:14:58,927 --> 00:15:04,047 to make sure that they lay their eggs in safe dry places. 168 00:15:04,807 --> 00:15:07,685 So you would think that dropping one into water 169 00:15:07,767 --> 00:15:09,519 would be a disaster. 170 00:15:09,607 --> 00:15:10,960 But watch. 171 00:15:37,527 --> 00:15:40,041 A fully developed baby turtle. 172 00:15:42,847 --> 00:15:46,203 And it has come from an egg which as far as we know is unique 173 00:15:46,367 --> 00:15:47,720 in the reptile world. 174 00:15:47,807 --> 00:15:50,526 It can not only survive being flooded 175 00:15:50,607 --> 00:15:55,397 it actually requires to be submerged in water in order to hatch. 176 00:15:56,887 --> 00:16:00,562 This enables the pig-nose to make the hatching of its eggs 177 00:16:00,647 --> 00:16:03,923 coincide with the onset of the rainy season. 178 00:16:05,927 --> 00:16:07,883 A view inside the egg 179 00:16:07,967 --> 00:16:11,721 would show the babies to be fully developed. 180 00:16:15,447 --> 00:16:19,679 They can remain there in a kind of suspended animation if necessary 181 00:16:19,767 --> 00:16:21,166 for weeks. 182 00:16:24,087 --> 00:16:26,203 (THUNDER CLAPPING) 183 00:16:31,287 --> 00:16:35,360 When the rains finally arrive they are torrential. 184 00:16:36,847 --> 00:16:41,159 The river rises swiftly and soon the nests are flooded. 185 00:16:53,567 --> 00:16:56,286 This would be a disaster for most turtles 186 00:16:56,367 --> 00:16:59,564 but the unhatched pig-noses are ready for it. 187 00:17:01,367 --> 00:17:04,564 Indeed its the moment theyve been waiting for. 188 00:17:24,127 --> 00:17:27,324 Their unique waiting strategy ensures that 189 00:17:27,407 --> 00:17:31,116 no matter how late the rains are the young turtles only emerge 190 00:17:31,207 --> 00:17:34,244 when the rivers are full and theres plenty to eat. 191 00:17:39,847 --> 00:17:42,520 Theyre able to swim immediately. 192 00:17:48,767 --> 00:17:49,756 In due course 193 00:17:49,847 --> 00:17:54,159 the females among them will return here to lay eggs themselves. 194 00:17:55,887 --> 00:17:59,516 The males however will never set foot on dry land again. 195 00:18:03,287 --> 00:18:07,599 No turtles are better suited to life in fresh water than the pig-nose. 196 00:18:07,927 --> 00:18:10,760 But the most extreme adaptations for swimming 197 00:18:10,847 --> 00:18:14,157 are found in those turtles that went to sea. 198 00:18:22,087 --> 00:18:23,566 Marine turtles 199 00:18:23,647 --> 00:18:26,207 have altered their front legs really radically 200 00:18:26,287 --> 00:18:29,006 and turned them into oar-like flippers. 201 00:18:32,807 --> 00:18:37,198 Theyre so at home in the sea they even mate while swimming. 202 00:18:42,007 --> 00:18:45,682 The male turtle has special hooks on his front flippers 203 00:18:45,767 --> 00:18:48,918 that enable him to cling onto the females shell. 204 00:18:49,007 --> 00:18:51,157 And he has to have a firm grip 205 00:18:51,247 --> 00:18:54,523 for she makes no allowance for him as she swims. 206 00:18:58,447 --> 00:19:03,760 But hanging onto his female is going to get much harder for this male. 207 00:19:04,807 --> 00:19:06,763 A rival has appeared. 208 00:19:10,327 --> 00:19:13,524 The males armour protects most of his body 209 00:19:13,607 --> 00:19:15,802 but his rear flippers are exposed 210 00:19:15,887 --> 00:19:19,004 and they are relatively soft and vulnerable. 211 00:19:35,207 --> 00:19:37,721 There can be little doubt that this hurts 212 00:19:37,807 --> 00:19:40,844 but theres not much that the first male can do about it. 213 00:19:42,087 --> 00:19:44,203 If he lets go with even a single flipper 214 00:19:44,287 --> 00:19:46,926 he will lose his grip and his female. 215 00:19:55,007 --> 00:19:58,556 The rival tries again and attacks the front flipper. 216 00:20:13,047 --> 00:20:16,517 And now the males troubles are about to double. 217 00:20:18,847 --> 00:20:21,202 A second rival arrives. 218 00:20:30,007 --> 00:20:35,001 The two challengers join forces and attack the male from both sides. 219 00:20:45,007 --> 00:20:48,238 His only option is to grin and bear it. 220 00:20:52,607 --> 00:20:56,077 Now a third hopeful male joins in. 221 00:20:58,887 --> 00:21:01,526 The female tries to shake them off 222 00:21:01,607 --> 00:21:03,165 but theres no shifting them. 223 00:21:13,447 --> 00:21:15,517 Its going from bad to worse. 224 00:21:15,607 --> 00:21:18,838 Even more males gang up on the hapless couple. 225 00:21:22,207 --> 00:21:26,200 Some of the gang try to force themselves between the mating pair. 226 00:21:36,367 --> 00:21:39,165 The pair have now been submerged for a long time 227 00:21:39,247 --> 00:21:42,444 and both of them are in desperate need of a breath. 228 00:21:44,127 --> 00:21:47,199 If the rivals can prevent the male from reaching the surface 229 00:21:47,287 --> 00:21:52,281 he will have no choice but to let go. Hes in real danger of drowning. 230 00:22:06,407 --> 00:22:09,683 At last the determined couple break free 231 00:22:09,767 --> 00:22:11,758 and make a dash for the surface. 232 00:22:20,207 --> 00:22:23,916 With a welcome gasp of air the pair escape. 233 00:22:37,207 --> 00:22:39,846 One by one the gang give up. 234 00:22:51,247 --> 00:22:55,957 It was over 200 million years ago that the first turtles took to the water. 235 00:22:56,247 --> 00:22:57,885 But they were not alone. 236 00:22:57,967 --> 00:23:01,960 Another group of reptiles were also making the same move 237 00:23:02,047 --> 00:23:04,720 and they too were armoured giants. 238 00:23:13,727 --> 00:23:16,799 Crocodilians like turtles and tortoises 239 00:23:16,887 --> 00:23:20,197 have barely changed since the time of the dinosaurs. 240 00:23:28,527 --> 00:23:32,156 Today crocodiles caiman and alligators 241 00:23:32,247 --> 00:23:35,205 live in tropical waters throughout the world. 242 00:23:37,647 --> 00:23:41,845 Crocodiles and tortoises are obviously very different 243 00:23:42,887 --> 00:23:45,640 but they do have one thing in common. 244 00:23:45,727 --> 00:23:47,160 Armour. 245 00:23:47,247 --> 00:23:51,957 Their bodies are encased by tough thick scales 246 00:23:52,047 --> 00:23:54,163 particularly along the back. 247 00:23:55,327 --> 00:23:58,319 In tortoises that armour is clearly defensive. 248 00:23:59,647 --> 00:24:03,083 But for crocodiles it has an extra function. 249 00:24:04,207 --> 00:24:08,837 just below each of these scales lies a network of blood vessels. 250 00:24:09,767 --> 00:24:13,999 A crocodile can control the flow of the blood within them. 251 00:24:14,087 --> 00:24:17,079 When basking it allows it to circulate freely 252 00:24:17,167 --> 00:24:21,957 so transferring the suns warmth from these ridged scales 253 00:24:22,047 --> 00:24:23,560 to the rest of its body. 254 00:24:24,207 --> 00:24:28,917 The crocodile in short has rows of very effective solar panels 255 00:24:29,007 --> 00:24:30,599 all down its back. 256 00:24:34,207 --> 00:24:39,964 And a sophisticated solar heating system like that is a very valuable facility 257 00:24:40,047 --> 00:24:41,685 for a cold-blooded creature. 258 00:24:49,367 --> 00:24:54,157 Being cold-blooded brings considerable advantages to a crocodile. 259 00:24:54,247 --> 00:24:57,319 Whereas a warm-blooded predator like a lion 260 00:24:57,407 --> 00:25:00,080 would die if it didnt feed every few days 261 00:25:00,167 --> 00:25:04,365 a crocodile if necessary can go without food for months on end. 262 00:25:05,007 --> 00:25:07,965 And that means that crocodiles can live in places 263 00:25:08,047 --> 00:25:10,959 where no warm-blooded predator could survive 264 00:25:11,847 --> 00:25:13,803 and wait for events 265 00:25:13,887 --> 00:25:16,879 that only happen two or three times each year. 266 00:25:17,687 --> 00:25:20,759 And one of those events will occur tonight 267 00:25:21,447 --> 00:25:22,846 right here. 268 00:25:24,607 --> 00:25:28,441 This road in northern Australia is close to the coast 269 00:25:28,527 --> 00:25:30,882 and it floods at the highest tides. 270 00:25:38,087 --> 00:25:41,602 Night falls and the scene changes dramatically. 271 00:25:46,647 --> 00:25:48,763 The road is now covered in water 272 00:25:49,447 --> 00:25:51,005 and crocodiles. 273 00:25:57,207 --> 00:25:59,801 But this is no random gathering. 274 00:26:00,447 --> 00:26:03,280 The crocodiles are all here for a reason. 275 00:26:09,047 --> 00:26:12,596 We know that some of them have travelled over 60 miles 276 00:26:12,687 --> 00:26:14,996 1 00 kilometres to get here. 277 00:26:25,367 --> 00:26:29,406 But how they know when to come here we have little idea. 278 00:26:42,007 --> 00:26:46,398 There must be some 40 crocodiles 279 00:26:46,487 --> 00:26:49,445 assembled in the river behind me. 280 00:26:49,887 --> 00:26:53,243 And what makes that sight all the more remarkable 281 00:26:53,367 --> 00:26:56,325 is that these are saltwater crocodiles 282 00:26:56,407 --> 00:27:00,002 which are normally very territorial and intolerant 283 00:27:00,087 --> 00:27:01,600 of one another. 284 00:27:01,687 --> 00:27:04,724 So there must be something pretty special happening 285 00:27:04,807 --> 00:27:09,039 in the river tonight and indeed there is. 286 00:27:09,447 --> 00:27:12,007 This river is tidal 287 00:27:12,087 --> 00:27:15,966 but its been crossed by a barrage. 288 00:27:16,047 --> 00:27:19,756 However at particularly high tides 289 00:27:19,847 --> 00:27:23,317 the water flows over the barrage. 290 00:27:23,407 --> 00:27:28,561 And that is the moment that all these crocodiles are waiting for. 291 00:27:30,887 --> 00:27:33,845 With the salt water come fish. 292 00:27:34,247 --> 00:27:38,081 Mullet have been waiting for weeks to migrate up the river to breed. 293 00:27:38,167 --> 00:27:42,558 This high tide is their first chance to cross the barrage. 294 00:27:47,967 --> 00:27:50,686 And the crocodiles are waiting for them. 295 00:27:58,527 --> 00:28:01,087 Remember its now pitch dark. 296 00:28:01,527 --> 00:28:04,599 Our infrared cameras give us a clear view 297 00:28:04,687 --> 00:28:07,485 but the crocodiles can see virtually nothing. 298 00:28:07,567 --> 00:28:11,526 So they wait with open jaws ready to snap them shut 299 00:28:11,607 --> 00:28:13,325 at the first touch of a fish. 300 00:28:30,367 --> 00:28:35,441 Normally saltwater crocodiles would not tolerate being so close to each other. 301 00:28:50,687 --> 00:28:53,724 They do compete for the best fishing spots 302 00:28:53,807 --> 00:28:57,595 but their disputes are settled with the minimum of fuss. 303 00:29:12,767 --> 00:29:15,440 The fish keep coming for over an hour 304 00:29:16,367 --> 00:29:20,360 but as the tide starts to fall so their numbers dwindle. 305 00:29:27,287 --> 00:29:32,964 With so many crocodiles competing some inevitably go hungry. 306 00:29:34,607 --> 00:29:36,563 But for those that stay around 307 00:29:36,647 --> 00:29:40,162 there will be a second bite to this particular cherry. 308 00:29:45,527 --> 00:29:50,203 The next high tide comes during the day and brings yet more fish. 309 00:29:57,847 --> 00:29:59,883 The crocodiles can now see the fish 310 00:29:59,967 --> 00:30:03,198 but that doesnt seem to make them any easier to catch. 311 00:30:22,207 --> 00:30:25,358 These skilful hunters are surely dramatic proof 312 00:30:25,447 --> 00:30:29,679 that reptiles are certainly not simple-minded creatures. 313 00:30:29,767 --> 00:30:32,327 Theyve predicted the time of the arrival of the fish 314 00:30:32,407 --> 00:30:34,159 with astonishing accuracy 315 00:30:34,247 --> 00:30:37,478 and they have worked out just what they have to do to catch them. 316 00:30:58,487 --> 00:31:03,242 They have also managed to suppress their normal antagonism to one another 317 00:31:03,327 --> 00:31:06,763 so that they can all take advantage of this bonanza. 318 00:31:15,687 --> 00:31:18,326 The more we learn about crocodiles 319 00:31:18,407 --> 00:31:22,002 the more we realise what complex creatures they are. 320 00:31:33,887 --> 00:31:36,162 Despite what you might think 321 00:31:36,247 --> 00:31:41,844 crocodilians are among the most talkative of reptiles and amphibians. 322 00:31:41,927 --> 00:31:47,081 Indeed theyre second only to the frogs in the variety of noises that they make. 323 00:31:48,127 --> 00:31:53,281 The most impressive of sounds of all come from the American alligator. 324 00:31:53,807 --> 00:31:55,718 When the breeding season starts 325 00:31:55,807 --> 00:31:59,925 the males begin to proclaim their ownership of territories. 326 00:32:00,927 --> 00:32:03,487 (INHALING) 327 00:32:11,047 --> 00:32:13,561 (EXHALING) 328 00:32:14,647 --> 00:32:17,207 (BELLOWING) 329 00:32:18,607 --> 00:32:21,405 The vibrations in his body are so powerful 330 00:32:21,487 --> 00:32:24,240 they make the water dance along his back. 331 00:32:24,407 --> 00:32:26,557 (BELLOWING) 332 00:32:36,567 --> 00:32:39,559 (DISTANT BELLOWING) 333 00:32:45,647 --> 00:32:49,435 Sound travels through water even better than it does through air 334 00:32:49,527 --> 00:32:53,679 and he can be heard by other alligators hundreds of metres away. 335 00:32:54,607 --> 00:32:58,486 This is a clear statement of ownership of territory. 336 00:33:02,127 --> 00:33:05,358 Thats fine when he does it lying in his own patch 337 00:33:05,447 --> 00:33:09,235 but watch what happens when he bellows close to another male. 338 00:33:42,287 --> 00:33:45,279 But the rivals dont come to blows. 339 00:33:45,367 --> 00:33:48,643 They sort out their differences with gestures. 340 00:33:51,287 --> 00:33:55,041 Head slaps and gaping jaws are very obvious signals 341 00:33:55,127 --> 00:33:59,325 but alligators also send messages in less conspicuous ways. 342 00:33:59,887 --> 00:34:03,436 Raising their backs slightly above the surface of the water 343 00:34:03,527 --> 00:34:06,997 is a significant move. Its a claim to dominance. 344 00:34:10,807 --> 00:34:14,356 Using signals that are almost imperceptible to us 345 00:34:14,447 --> 00:34:17,519 all these individuals are sending messages to each other 346 00:34:17,607 --> 00:34:20,360 making claim and counterclaim. 347 00:34:25,007 --> 00:34:28,761 Communication between alligators can be very subtle 348 00:34:29,407 --> 00:34:32,126 quiet but there are some occasions 349 00:34:32,207 --> 00:34:36,883 when they really want to make their meaning very unambiguously clear. 350 00:34:37,607 --> 00:34:41,441 And one of those is when theyre guarding their nests 351 00:34:42,127 --> 00:34:43,606 as this one is. 352 00:34:52,287 --> 00:34:54,676 (GROWLING) 353 00:34:56,087 --> 00:34:57,759 I think that was pretty clear. 354 00:34:57,847 --> 00:34:59,439 (CHUCKLING) Oh dear. 355 00:35:00,487 --> 00:35:03,285 Anyway I wont press the point. 356 00:35:09,327 --> 00:35:14,276 Communication between crocodiles starts even before theyve hatched. 357 00:35:14,967 --> 00:35:16,958 (CHIRPING) 358 00:35:20,407 --> 00:35:23,365 A tranquil pool in Argentina 359 00:35:23,447 --> 00:35:26,837 and in it a female broad-snouted caiman. 360 00:35:29,487 --> 00:35:33,196 She laid her eggs in a pile of vegetation close to the water 361 00:35:33,287 --> 00:35:35,084 almost three months ago. 362 00:35:35,167 --> 00:35:37,522 Now sounds are coming from it. 363 00:35:38,687 --> 00:35:41,076 The eggs are beginning to hatch. 364 00:35:43,527 --> 00:35:45,006 (CHIRPING) 365 00:35:45,287 --> 00:35:47,926 Even while the eggs are still within the nest 366 00:35:48,007 --> 00:35:50,805 their mother can hear them from some way away. 367 00:35:58,687 --> 00:36:00,996 (CHIRPING) 368 00:36:11,567 --> 00:36:14,764 Back on the nest she listens intently. 369 00:36:17,087 --> 00:36:18,486 (MUFFLED CHIRPING) 370 00:36:26,407 --> 00:36:31,242 Then very gently she starts to take it apart. 371 00:36:35,927 --> 00:36:39,044 She cant know exactly where each of her babies is 372 00:36:39,127 --> 00:36:41,800 and stops every few seconds to listen. 373 00:36:45,727 --> 00:36:47,285 (CHIRPING) 374 00:36:57,087 --> 00:36:59,840 At last the young are free. 375 00:37:01,127 --> 00:37:02,879 But she doesnt abandon them. 376 00:37:11,567 --> 00:37:13,683 She is going to take them down to the pool 377 00:37:13,767 --> 00:37:16,076 that she has selected as their nursery. 378 00:37:20,967 --> 00:37:24,357 Some babies start to make the journey for themselves 379 00:37:24,447 --> 00:37:28,440 but they continue to call and that helps their mother locate them. 380 00:37:29,327 --> 00:37:31,079 (DISTANT CHIRPING) 381 00:37:40,127 --> 00:37:44,040 Caiman jaws are among the strongest in the animal kingdom 382 00:37:44,127 --> 00:37:49,201 but now she uses hers with the greatest delicacy and gentleness. 383 00:38:13,687 --> 00:38:18,522 So at last her babies are brought together in the nursery pool. 384 00:38:26,807 --> 00:38:29,924 But their mothers job is still not finished. 385 00:38:32,567 --> 00:38:35,365 Several of the eggs have failed to hatch. 386 00:38:38,407 --> 00:38:39,965 (BABIES CHIRPING) 387 00:38:41,807 --> 00:38:45,595 One by one she takes these in her mouth. 388 00:38:52,847 --> 00:38:55,645 The shell around the egg is quite strong. 389 00:38:55,727 --> 00:38:59,163 The babies must make a considerable effort to free themselves 390 00:38:59,247 --> 00:39:01,966 and for some its more than they can manage. 391 00:39:03,407 --> 00:39:08,481 So she starts to crack the unhatched egg with her teeth. 392 00:39:21,567 --> 00:39:24,035 Once the hard shell has been broken away 393 00:39:24,127 --> 00:39:27,119 she has to pierce the leathery inner membrane. 394 00:39:47,087 --> 00:39:51,399 Without her help this baby might not have hatched at all. 395 00:40:04,927 --> 00:40:10,081 But the female caimans maternal duties are not over even now. 396 00:40:10,167 --> 00:40:14,240 She will stand guard over her babies for the next few months. 397 00:40:16,727 --> 00:40:20,242 All crocodilians take good care of their young 398 00:40:20,327 --> 00:40:23,160 but one of them takes parental responsibilities 399 00:40:23,247 --> 00:40:25,477 to a really astonishing level. 400 00:40:29,327 --> 00:40:31,522 The Llanos of Venezuela 401 00:40:31,607 --> 00:40:35,885 a lush wetland teeming with wildlife of all kinds. 402 00:40:43,287 --> 00:40:46,359 As well as birds there are amphibious rodents 403 00:40:46,447 --> 00:40:49,564 capybara and spectacled caiman. 404 00:40:57,487 --> 00:41:03,676 This female is looking after an extraordinarily large number of babies. 405 00:41:05,807 --> 00:41:09,004 But most of these are not in fact hers. 406 00:41:16,047 --> 00:41:20,723 This nursery pool is being used by several caiman families. 407 00:41:20,807 --> 00:41:23,367 But instead of all the mothers staying nearby 408 00:41:23,447 --> 00:41:26,598 one of them has taken charge of the whole creche. 409 00:41:32,207 --> 00:41:36,598 Keeping an eye on all these energetic babies is not easy. 410 00:41:37,407 --> 00:41:39,716 There are lots of enemies around. 411 00:41:52,327 --> 00:41:56,445 When danger threatens the babies all run for protection to the female 412 00:41:56,527 --> 00:41:59,246 even though she may not be their mother. 413 00:42:03,807 --> 00:42:05,240 There are so many of them 414 00:42:05,327 --> 00:42:08,876 that theres not enough room for them all on her back. 415 00:42:18,367 --> 00:42:21,803 Soon these babies will face another hazard 416 00:42:21,887 --> 00:42:25,004 and one thats not quite so easy to escape from. 417 00:42:27,167 --> 00:42:29,806 The water that has kept them safe until now 418 00:42:29,887 --> 00:42:31,798 is beginning to dry up. 419 00:42:32,847 --> 00:42:35,964 Each year in the space of a few short months 420 00:42:36,047 --> 00:42:41,326 the Llanos is transformed from a flooded paradise to a baking oven. 421 00:42:44,287 --> 00:42:47,916 For some babies the unrelenting heat and the lack of water 422 00:42:48,007 --> 00:42:50,077 has already been too much. 423 00:43:00,327 --> 00:43:05,401 Any babies that are left alive will certainly die if they stay here. 424 00:43:08,927 --> 00:43:11,839 So the mother decides to leave. 425 00:43:16,567 --> 00:43:18,046 (LOW CHIRPING) 426 00:43:24,087 --> 00:43:26,726 (FEMALE CONTINUES CHIRPING) 427 00:43:29,887 --> 00:43:34,915 Calling to her creche she sets off across the parched land. 428 00:43:36,167 --> 00:43:41,525 In one long cavalcade they march onwards in search of permanent water. 429 00:43:59,967 --> 00:44:03,277 For the mother this is certainly exhausting. 430 00:44:03,367 --> 00:44:07,883 For her babies with their tiny legs it must be a real marathon. 431 00:44:10,407 --> 00:44:12,875 (CHIRPING) 432 00:44:17,727 --> 00:44:20,036 Some start to fall behind. 433 00:44:21,927 --> 00:44:23,440 But she stops. 434 00:44:27,647 --> 00:44:32,118 The babies call constantly. She knows exactly where they all are 435 00:44:32,207 --> 00:44:35,722 and waits until every single one of them has caught up. 436 00:44:58,567 --> 00:45:02,321 Only when all are with her will she set off again. 437 00:45:23,607 --> 00:45:25,723 At last safety. 438 00:45:36,167 --> 00:45:39,204 The babies are close to exhaustion. 439 00:45:52,167 --> 00:45:55,125 Without such devotion from the female 440 00:45:55,207 --> 00:45:58,756 few if any of these baby caiman would have survived. 441 00:45:59,887 --> 00:46:03,675 And remarkably most of them arent even her own. 442 00:46:13,367 --> 00:46:16,837 When parental care was first described in crocodiles 443 00:46:16,927 --> 00:46:20,636 the reports were dismissed as too extraordinary to be true. 444 00:46:25,687 --> 00:46:30,841 We may call reptiles cold-blooded but they can show great tenderness. 445 00:46:34,927 --> 00:46:38,886 Reptiles and amphibians are full of surprises. 446 00:46:57,807 --> 00:47:01,925 They can look after their young with as much care as many a mammal. 447 00:47:09,327 --> 00:47:13,286 Their displays can be as colourful as that of any bird. 448 00:47:17,807 --> 00:47:21,163 And they can astonish and enthral us. 449 00:47:34,567 --> 00:47:40,722 Reptiles and amphibians are sometimes seen as simple primitive creatures. 450 00:47:40,807 --> 00:47:43,605 Thats a long way from the truth. 451 00:47:43,687 --> 00:47:45,962 The fact that they are solar-powered 452 00:47:46,047 --> 00:47:49,960 means that their bodies require only 10% of the energy 453 00:47:50,047 --> 00:47:53,278 that mammals of a similar size require. 454 00:47:54,007 --> 00:47:58,558 At a time when we ourselves are becoming increasingly concerned 455 00:47:58,647 --> 00:48:02,686 about the way in which we get our energy from the environment 456 00:48:02,767 --> 00:48:05,235 and the wasteful way in which we use it 457 00:48:05,327 --> 00:48:10,117 maybe there are things that we can learn from life in cold blood. 458 00:48:33,167 --> 00:48:36,159 We filmed a lot of different reptiles and amphibians 459 00:48:36,247 --> 00:48:38,044 during the making of this series. 460 00:48:46,367 --> 00:48:49,040 We were looking for extraordinary behaviour 461 00:48:49,127 --> 00:48:52,642 preferably for things that had never been filmed before. 462 00:49:02,567 --> 00:49:05,923 To see such wonders we needed the help of scientists 463 00:49:06,007 --> 00:49:07,201 who were working in the field. 464 00:49:07,287 --> 00:49:09,198 ...actually quite thin. 465 00:49:10,607 --> 00:49:12,199 Point it a little bit more... 466 00:49:12,287 --> 00:49:15,643 ATTENBOROUGH: They passed onto us their insights and their discoveries 467 00:49:15,727 --> 00:49:19,606 and then they helped us to interpret the footage that we had shot. 468 00:49:19,687 --> 00:49:21,837 I learnt a lot and had a lot of fun. 469 00:49:23,327 --> 00:49:26,000 But I was also alarmed to discover just how rare 470 00:49:26,087 --> 00:49:29,159 some of the subjects of our series have now become. 471 00:49:33,407 --> 00:49:36,683 One of our key locations was the Galapagos Islands. 472 00:49:36,767 --> 00:49:40,316 Here giant tortoises were going be among our stars. 473 00:49:40,407 --> 00:49:43,717 The scientists working for the Galapagos National Parks 474 00:49:43,807 --> 00:49:46,367 care for the wild animal populations 475 00:49:46,447 --> 00:49:50,122 but they also look after one extraordinary unique individual 476 00:49:50,207 --> 00:49:52,675 with whom I had a special appointment. 477 00:49:53,607 --> 00:49:58,123 This is the rarest living animal in all the world. 478 00:49:58,847 --> 00:50:00,439 There is none rarer. 479 00:50:01,487 --> 00:50:04,001 This is Lonesome George. 480 00:50:05,327 --> 00:50:07,761 He is about the same age as I am 481 00:50:07,847 --> 00:50:10,884 but his story starts a very long time ago. 482 00:50:11,967 --> 00:50:16,404 In the 1 7th century when human beings first came to the Galapagos 483 00:50:18,007 --> 00:50:22,637 there were about 1 2 different kinds of giant tortoise 484 00:50:22,887 --> 00:50:27,244 each living on its own island or its own great volcano 485 00:50:27,327 --> 00:50:30,763 isolated by unpassable lava flows. 486 00:50:33,327 --> 00:50:37,479 There are 1 3 large islands in the Galapagos and many smaller ones 487 00:50:37,567 --> 00:50:41,196 and they differ in both age and their vegetation. 488 00:50:41,767 --> 00:50:45,043 The tortoises differ too because their shells have evolved into 489 00:50:45,127 --> 00:50:48,517 the different shapes best suited for eating the food available 490 00:50:48,607 --> 00:50:50,643 on their own particular island. 491 00:50:51,247 --> 00:50:53,681 On islands where theres abundant food on the ground 492 00:50:53,767 --> 00:50:56,998 the tortoises have dome-shaped shells and short necks 493 00:50:57,087 --> 00:50:58,918 that only need reach downwards. 494 00:51:00,407 --> 00:51:03,877 But on islands where the tortoises browse on higher bushes 495 00:51:03,967 --> 00:51:07,801 their necks are longer and the shells are saddle-shaped at the front 496 00:51:07,887 --> 00:51:11,641 so they can stretch their necks upwards. 497 00:51:11,727 --> 00:51:13,524 When the first ships arrived here 498 00:51:13,607 --> 00:51:16,360 there were thousands of each kind of tortoise. 499 00:51:17,727 --> 00:51:22,482 But then people began to slaughter the tortoises for meat. 500 00:51:23,687 --> 00:51:26,565 They discovered the remarkable fact 501 00:51:26,687 --> 00:51:32,523 that these creatures could live for a year without water or food 502 00:51:33,607 --> 00:51:37,919 so they took them on board their ships and slaughtered them at sea. 503 00:51:38,927 --> 00:51:42,681 The tortoises on Pinta Island were apparently exterminated. 504 00:51:43,887 --> 00:51:46,924 But then in 1 971 505 00:51:47,767 --> 00:51:54,525 it was discovered that there was one lonely single survivor. 506 00:51:55,647 --> 00:51:57,797 That was Lonesome George. 507 00:52:00,127 --> 00:52:04,086 This film was taken over 30 years ago by the team that brought George back 508 00:52:04,167 --> 00:52:06,601 to the Charles Darwin Research Station. 509 00:52:06,687 --> 00:52:09,520 The scientists hoped that another Pinta tortoise might be discovered 510 00:52:09,607 --> 00:52:13,839 in some corner of this island or even in a zoo somewhere in the world. 511 00:52:13,927 --> 00:52:16,077 But none has ever been found. 512 00:52:20,967 --> 00:52:23,800 So now George lives in his own enclosure 513 00:52:23,887 --> 00:52:27,084 completely safe but entirely by himself. 514 00:52:27,167 --> 00:52:28,919 Hes the last of his kind. 515 00:52:29,727 --> 00:52:33,276 Its better news for the other Galapagos tortoises. 516 00:52:33,367 --> 00:52:35,642 Felipe Cruz from the research station 517 00:52:35,727 --> 00:52:38,116 showed me some of the work being done there. 518 00:52:38,887 --> 00:52:43,165 They take eggs laid by wild tortoises and put them in incubators. 519 00:52:43,967 --> 00:52:47,562 The hatchlings are about the size of apples and have soft shells 520 00:52:47,647 --> 00:52:50,605 so are vulnerable to predators especially rats 521 00:52:50,687 --> 00:52:53,201 that were accidentally introduced to the Galapagos. 522 00:52:53,287 --> 00:52:55,926 They will keep this number for their life. 523 00:52:56,767 --> 00:52:59,839 ATTENBOROUGH: The young ones I saw were only a few months old. 524 00:53:00,687 --> 00:53:04,441 Theyre kept in special enclosures and given all the foods they need 525 00:53:04,527 --> 00:53:07,599 to enable them to develop hard protective shells. 526 00:53:09,727 --> 00:53:12,446 It takes a few months for their shells to harden 527 00:53:12,527 --> 00:53:15,997 and its five years before theyre totally predator proof. 528 00:53:22,607 --> 00:53:27,601 So far in total we have repatriated over 3000 tortoises. 529 00:53:27,687 --> 00:53:30,326 -Three thousand? -In the different islands. 530 00:53:30,727 --> 00:53:32,718 ATTENBOROUGH: Scientists are also helping to solve 531 00:53:32,807 --> 00:53:34,763 another man-made problem. 532 00:53:36,607 --> 00:53:40,805 Domestic goats that have run wild are eating the tortoises food 533 00:53:40,887 --> 00:53:44,641 and destroying the precious plant cover that they need for shade. 534 00:53:44,727 --> 00:53:48,083 So a systematic programme of eradication has started. 535 00:53:56,447 --> 00:53:59,678 I was able to see the effects of this programme for myself. 536 00:53:59,767 --> 00:54:02,156 We visited one island where two years earlier 537 00:54:02,247 --> 00:54:03,760 the goats had been eliminated 538 00:54:03,847 --> 00:54:05,883 and the difference was dramatic. 539 00:54:05,967 --> 00:54:08,117 The lush vegetation had returned. 540 00:54:09,927 --> 00:54:14,523 Now the tortoises can find the shade that is so important for them 541 00:54:14,607 --> 00:54:17,485 and theres plenty of grass for them to eat. 542 00:54:24,687 --> 00:54:27,485 Reptiles are not alone in being under threat. 543 00:54:28,567 --> 00:54:32,640 The amphibians if anything are in even greater danger. 544 00:54:32,727 --> 00:54:35,082 Not since the disappearance of the dinosaurs 545 00:54:35,167 --> 00:54:39,126 has a whole group of the animal kingdom been under such threat. 546 00:54:39,807 --> 00:54:44,358 In Japan one of the most dramatic of amphibians the giant salamander 547 00:54:44,447 --> 00:54:46,722 has fewer and fewer places to live. 548 00:54:52,367 --> 00:54:55,439 In Panama we filmed the golden frog. 549 00:54:55,527 --> 00:54:58,837 Since we took this shot the species has become so rare 550 00:54:58,927 --> 00:55:02,966 that the few survivors have been caught to be protected in zoos. 551 00:55:03,047 --> 00:55:05,436 So its now extinct in the wild. 552 00:55:07,807 --> 00:55:10,367 The gharials that we filmed with their babies 553 00:55:10,447 --> 00:55:12,836 were nearly exterminated in the 1 970s 554 00:55:12,927 --> 00:55:15,316 when they lost most of their natural habitat. 555 00:55:15,407 --> 00:55:17,125 And theyre not safe yet. 556 00:55:18,567 --> 00:55:22,321 To try and halt their decline their eggs are being collected 557 00:55:22,407 --> 00:55:25,638 hatched in incubators and the babies reared in captivity 558 00:55:25,727 --> 00:55:28,161 until they can be released in the wild. 559 00:55:28,247 --> 00:55:30,522 So there may be hope for them yet. 560 00:55:31,927 --> 00:55:35,556 The gopher tortoise we filmed in Florida is also in trouble. 561 00:55:35,647 --> 00:55:39,322 The areas where it digs its burrows have become prime real estate 562 00:55:39,407 --> 00:55:42,444 and are now much sought after for building and farming. 563 00:55:44,487 --> 00:55:48,116 By explaining their problems to landowners and developers 564 00:55:48,207 --> 00:55:50,323 they may yet have a future. 565 00:55:55,487 --> 00:55:59,366 In the great island of Madagascar there are more species of chameleon 566 00:55:59,447 --> 00:56:01,677 than in all the rest of the world put together. 567 00:56:04,607 --> 00:56:07,075 But the destruction of the islands forests 568 00:56:07,167 --> 00:56:10,716 began centuries ago and only a few patches are left. 569 00:56:10,807 --> 00:56:12,763 They too are still being felled 570 00:56:12,847 --> 00:56:17,125 and chameleon species may be lost even before theyve been identified. 571 00:56:22,087 --> 00:56:24,760 We will need to act now if were not to lose 572 00:56:24,847 --> 00:56:27,680 what remains to us of the reptiles and amphibians 573 00:56:27,767 --> 00:56:30,964 that have survived for 200 million years. 574 00:56:32,647 --> 00:56:37,323 Lonesome George it seems is doomed to be the last of his kind 575 00:56:38,367 --> 00:56:42,679 but at least he can be a living inspiration for us all 576 00:56:43,367 --> 00:56:49,363 to protect the remainder of the reptiles and amphibians of the world.