1 00:00:00,634 --> 00:00:03,301 ♪ ♪ 2 00:00:03,369 --> 00:00:06,604 Narrator: The southern end of the andes... 3 00:00:08,842 --> 00:00:15,314 Where a mother puma tries to raise a family. 4 00:00:17,584 --> 00:00:23,754 Andean condors soar over endless rainforests, 5 00:00:23,823 --> 00:00:28,659 Sheltering rare inhabitants. 6 00:00:29,263 --> 00:00:31,596 There are species of tree here 7 00:00:31,665 --> 00:00:36,602 That have outlasted the dinosaurs. 8 00:00:36,670 --> 00:00:40,539 In these remote southern reaches of patagonia, 9 00:00:40,607 --> 00:00:43,675 Everything must adapt... 10 00:00:43,744 --> 00:00:46,310 ... To constant upheaval... 11 00:00:46,379 --> 00:00:48,580 ... Invasion... 12 00:00:48,648 --> 00:00:52,451 ... And explosive change. 13 00:00:52,518 --> 00:00:58,556 Wild and untamed, this is life at the end of the world. 14 00:00:58,625 --> 00:01:02,494 [♪ theme music ♪] 15 00:01:17,778 --> 00:01:21,747 ♪ ♪ 16 00:01:48,275 --> 00:01:50,775 Narrator: Aconcagua. 17 00:01:50,844 --> 00:01:58,817 At nearly 23,000 feet it is the highest peak in the americas. 18 00:01:58,819 --> 00:02:03,755 Permanently cloaked in ice, and deeply carved by glaciers, 19 00:02:03,757 --> 00:02:12,030 Aconcagua straddles the border between chile and argentina. 20 00:02:15,636 --> 00:02:21,773 From here the andes stretch down through patagonia. 21 00:02:21,842 --> 00:02:28,647 An inhospitable land of rock towers and biting cold... 22 00:02:29,716 --> 00:02:33,652 Torres del paine, in the patagonian andes, 23 00:02:33,654 --> 00:02:39,891 Is a stronghold for one of the world's greatest hunters. 24 00:02:39,960 --> 00:02:41,860 The puma. 25 00:02:41,928 --> 00:02:46,031 ♪ ♪ 26 00:02:51,872 --> 00:02:54,172 This female is stalking another 27 00:02:54,241 --> 00:02:58,877 Of the mountains' hardy survivors: 28 00:02:58,946 --> 00:03:02,447 The guanaco. 29 00:03:19,165 --> 00:03:23,302 Hunter and hunted... 30 00:03:23,370 --> 00:03:31,710 Each must use all its senses to outmaneuver the other. 31 00:03:37,918 --> 00:03:41,186 But she's been spotted. 32 00:03:41,188 --> 00:03:47,159 The guanaco have a temporary reprieve. 33 00:03:48,395 --> 00:03:52,630 Here, wintry squalls can blow in with little warning, 34 00:03:52,699 --> 00:03:56,735 Even in summer. 35 00:04:05,211 --> 00:04:11,450 Bad weather makes every threat even more dangerous. 36 00:04:16,155 --> 00:04:18,789 Fortunately, guanaco are well-protected 37 00:04:18,858 --> 00:04:21,626 From the freezing temperatures. 38 00:04:21,629 --> 00:04:22,828 Their fleece is layered 39 00:04:22,896 --> 00:04:26,164 With short downy hair that keeps them warm, 40 00:04:26,233 --> 00:04:30,769 And long guard hair that waterproofs them. 41 00:04:32,706 --> 00:04:38,242 But hunger and fear are never far away. 42 00:04:41,815 --> 00:04:46,251 Icy winds swirl around the torres del paine, 43 00:04:46,319 --> 00:04:49,788 The towers of blue. 44 00:04:49,856 --> 00:04:54,793 At best, they make life unpredictable... 45 00:04:54,861 --> 00:04:56,560 At worst... 46 00:04:56,629 --> 00:04:59,431 Unbearable. 47 00:05:01,534 --> 00:05:06,071 Each valley harbors its own weather. 48 00:05:07,140 --> 00:05:11,343 Predators and prey must keep on the move 49 00:05:11,411 --> 00:05:13,544 If they want to avoid the worst 50 00:05:13,613 --> 00:05:17,581 These mountains can throw at them. 51 00:05:22,889 --> 00:05:29,428 Sheltered by the granite spires and surrounding peaks... 52 00:05:30,831 --> 00:05:34,366 ... Many of the slopes are free from snow, 53 00:05:34,368 --> 00:05:38,770 Making travel much easier. 54 00:05:42,576 --> 00:05:46,645 The female puma moves with determination, 55 00:05:46,713 --> 00:05:50,482 But she isn't hunting. 56 00:05:50,550 --> 00:05:55,053 Or, at least, not for food. 57 00:06:02,529 --> 00:06:07,031 A male puma. 58 00:06:07,100 --> 00:06:11,603 Females can come into heat at any time of year. 59 00:06:11,671 --> 00:06:16,774 Her pheromones signal she's ready to breed. 60 00:06:18,745 --> 00:06:26,284 [female puma yowling] 61 00:06:31,492 --> 00:06:33,691 They'll now spend a week together, 62 00:06:33,760 --> 00:06:42,167 Mating many times a day, before going their separate ways, 63 00:06:42,235 --> 00:06:48,273 Endlessly roaming the slopes of this vast landscape. 64 00:06:53,180 --> 00:06:54,679 ♪ ♪ 65 00:06:54,747 --> 00:06:59,651 The andes are the longest mountain chain in the world... 66 00:06:59,653 --> 00:07:02,053 ... Stretching 4,000 miles 67 00:07:02,055 --> 00:07:06,725 Along the entire western edge of south america. 68 00:07:06,793 --> 00:07:12,063 Parallel rocky spines snake from the tropics in the north, 69 00:07:12,065 --> 00:07:16,334 Down to the chill of patagonia. 70 00:07:16,403 --> 00:07:20,171 Here, the mountains have been carved by ice 71 00:07:20,240 --> 00:07:23,274 And are separated by deep fjords. 72 00:07:23,276 --> 00:07:26,043 Heading north from torres del paine, 73 00:07:26,112 --> 00:07:29,781 The mountains embrace some of the world's largest ice fields, 74 00:07:29,849 --> 00:07:34,219 And hundreds of active volcanoes. 75 00:07:34,287 --> 00:07:37,489 On the western slopes, in central chile, 76 00:07:37,556 --> 00:07:41,792 Lies one of the most southerly rainforests in the world. 77 00:07:41,861 --> 00:07:45,797 ♪ ♪ 78 00:07:56,242 --> 00:08:00,311 Moisturized by pacific fog, the valdivian forest 79 00:08:00,380 --> 00:08:04,649 Is bursting with natural treasures. 80 00:08:12,392 --> 00:08:14,792 Many of them are named after the man 81 00:08:14,795 --> 00:08:18,797 Who first discovered them... 82 00:08:18,865 --> 00:08:23,201 Including darwin's stag beetle. 83 00:08:23,270 --> 00:08:26,604 This male is about three and a half inches long, 84 00:08:26,673 --> 00:08:28,473 But its ferocious mandibles 85 00:08:28,541 --> 00:08:32,711 Account for more than half its length. 86 00:08:34,581 --> 00:08:39,351 From high in the canopy comes the irresistible smell 87 00:08:39,419 --> 00:08:44,622 Of a female's pheromones, luring him upwards. 88 00:08:44,691 --> 00:08:48,627 ♪ ♪ 89 00:08:54,768 --> 00:09:01,439 Along the way, he breaks for a restorative drink of sap. 90 00:09:03,142 --> 00:09:06,478 But he can't stop long. 91 00:09:07,246 --> 00:09:11,249 Competition is on its way. 92 00:09:11,251 --> 00:09:17,222 Another male, drawn to the same seductive scent. 93 00:09:21,128 --> 00:09:25,564 The rival takes to the air to make his ascent. 94 00:09:29,836 --> 00:09:34,439 They are heading for a treetop showdown. 95 00:09:35,808 --> 00:09:40,678 But will either of them have energy left for a fight? 96 00:09:40,747 --> 00:09:43,815 ♪ ♪ 97 00:09:43,817 --> 00:09:50,355 Sixty feet up, the stage is set for a clash of the titans. 98 00:09:50,890 --> 00:09:54,993 ♪ ♪ 99 00:10:03,837 --> 00:10:09,007 The two males square up to fight. 100 00:10:11,477 --> 00:10:13,778 The grappling begins. 101 00:10:13,846 --> 00:10:17,148 A kind of beetle jujitsu. 102 00:10:18,418 --> 00:10:19,684 The goal? 103 00:10:19,752 --> 00:10:22,720 To launch one's opponent from the branch. 104 00:10:22,789 --> 00:10:28,760 And win the right to mate with the female waiting nearby. 105 00:10:29,529 --> 00:10:34,899 The climber hooks his longer mandibles under the flier... 106 00:10:34,967 --> 00:10:38,402 And triumphs! 107 00:10:57,924 --> 00:11:01,793 ♪ ♪ 108 00:11:04,430 --> 00:11:07,298 The interloper survives the fall. 109 00:11:07,366 --> 00:11:11,703 But he's out of the running. 110 00:11:12,605 --> 00:11:17,174 Up above, the victor is already claiming his prize, 111 00:11:17,243 --> 00:11:22,047 Mating with the much smaller female. 112 00:11:23,382 --> 00:11:28,786 The fact that the winner usually boasts the largest mandibles 113 00:11:28,855 --> 00:11:31,790 Shows that with darwin's stag beetles, 114 00:11:31,858 --> 00:11:36,327 Size really does matter. 115 00:11:38,865 --> 00:11:41,632 Down in the mossy undergrowth 116 00:11:41,701 --> 00:11:45,903 Lives another of darwin's remarkable namesakes: 117 00:11:45,972 --> 00:11:49,140 Darwin's frog. 118 00:11:55,715 --> 00:12:00,085 It's not unusual for male frogs to look after their young, 119 00:12:00,153 --> 00:12:02,087 But the male darwin's frog 120 00:12:02,155 --> 00:12:07,091 Takes paternal responsibility to a whole new level. 121 00:12:07,160 --> 00:12:10,495 The brown female laid eggs in the leaf litter. 122 00:12:10,563 --> 00:12:15,100 Nearly a month ago. 123 00:12:18,538 --> 00:12:23,174 After she left, the male took the eggs into his vocal sac. 124 00:12:23,243 --> 00:12:26,744 Three days later, they hatched into tadpoles 125 00:12:26,813 --> 00:12:30,782 And have remained there ever since. 126 00:12:30,850 --> 00:12:34,585 For the next three months, the tadpoles will develop inside him 127 00:12:34,654 --> 00:12:39,824 Until they're mature enough to be spat out into the world. 128 00:12:39,892 --> 00:12:42,527 Along with darwin's frogs, 129 00:12:42,529 --> 00:12:45,563 An incredible 90 percent of species 130 00:12:45,631 --> 00:12:48,266 Found in the valdivian forest 131 00:12:48,334 --> 00:12:53,838 Have evolved to live only here -- 132 00:12:53,906 --> 00:13:01,012 Isolated by the towering uplift of the southern andes. 133 00:13:03,149 --> 00:13:07,585 The lush rainforests couldn't be more different 134 00:13:07,653 --> 00:13:11,622 To the barren land of torres del paine -- 135 00:13:11,625 --> 00:13:16,528 600 miles to the south. 136 00:13:19,499 --> 00:13:25,102 This is the realm of the puma -- 137 00:13:25,105 --> 00:13:31,476 And its many prey that scratch a living among the scrub. 138 00:13:38,584 --> 00:13:42,720 Today they're very much in the female's sights... 139 00:13:42,722 --> 00:13:45,256 ♪ ♪ 140 00:13:45,325 --> 00:13:52,030 ... Especially now she has three extra mouths to feed. 141 00:14:02,508 --> 00:14:07,678 For three months, she has hidden her kittens in a den. 142 00:14:07,681 --> 00:14:12,649 Now it's time to explore. 143 00:14:19,292 --> 00:14:27,232 Every step brings new adventures in this rocky world. 144 00:14:29,436 --> 00:14:35,306 For the first time, the mother lets the cubs run wild... 145 00:14:35,308 --> 00:14:40,345 Free to learn from their own mistakes. 146 00:14:43,883 --> 00:14:46,450 However, they will be many months 147 00:14:46,519 --> 00:14:48,719 Before they are wily enough 148 00:14:48,788 --> 00:14:55,259 Or fast enough to try to ambush a darwins rhea. 149 00:14:55,328 --> 00:14:58,196 [puma meows] 150 00:15:00,600 --> 00:15:03,034 Despite the abundance of prey, 151 00:15:03,102 --> 00:15:07,772 The kittens won't be hunting anytime soon. 152 00:15:18,851 --> 00:15:23,854 To keep them close, mom calls to them. 153 00:15:23,923 --> 00:15:27,325 [puma meowing] 154 00:15:30,363 --> 00:15:34,665 But sometimes curiosity gets the better of little cats. 155 00:15:34,734 --> 00:15:38,670 ♪ ♪ 156 00:15:49,115 --> 00:15:54,719 And wrangling kittens is no easy task. 157 00:15:58,124 --> 00:16:00,391 Fortunately, even though they're weaned, 158 00:16:00,459 --> 00:16:05,163 Her young know not to stray too far. 159 00:16:12,672 --> 00:16:16,140 Just one more to come. 160 00:16:16,208 --> 00:16:20,144 ♪ ♪ 161 00:16:25,885 --> 00:16:31,022 Now that they're all together, it's time to get them fed... 162 00:16:36,696 --> 00:16:40,231 A guanaco appears nearby... 163 00:16:40,233 --> 00:16:44,835 And the mother puma can smell her. 164 00:16:44,904 --> 00:16:49,007 ♪ ♪ 165 00:16:55,515 --> 00:16:59,517 The cubs follow. 166 00:17:02,688 --> 00:17:09,027 Time for their hunting lessons to begin. 167 00:17:26,312 --> 00:17:31,215 Above the valdivian forest in central chile, 168 00:17:31,217 --> 00:17:37,154 Living fossils adorn the mountain slopes. 169 00:17:37,223 --> 00:17:42,126 Araucaria trees have been around for 200 million years, 170 00:17:42,194 --> 00:17:47,165 Since the time of the earliest dinosaurs. 171 00:17:50,703 --> 00:17:54,638 The araucaria are an important source of food 172 00:17:54,707 --> 00:17:59,110 For austral parakeets. 173 00:18:02,848 --> 00:18:07,651 The sharp leaves are no impediment to the hungry birds, 174 00:18:07,654 --> 00:18:13,291 On the hunt for the calorie-rich kernels. 175 00:18:23,802 --> 00:18:26,303 It's thought that long-necked dinosaurs 176 00:18:26,371 --> 00:18:30,607 Would once have fed on these seed cones. 177 00:18:30,610 --> 00:18:36,180 Now only birds can get this high. 178 00:18:39,185 --> 00:18:43,154 Incredibly, this ancient species of tree 179 00:18:43,222 --> 00:18:47,625 Has been around longer than the mountains beneath them, 180 00:18:47,693 --> 00:18:52,163 Including llaima -- one of chile's most active volcanoes. 181 00:18:52,231 --> 00:18:56,167 ♪ ♪ 182 00:18:56,769 --> 00:19:00,304 Araucaria have outlived the dinosaurs, 183 00:19:00,372 --> 00:19:04,142 And weathered the rise of the andes. 184 00:19:04,777 --> 00:19:09,347 But they've had some help along the way. 185 00:19:17,756 --> 00:19:23,794 Beneath the araucaria trees lives a small rodent... 186 00:19:23,862 --> 00:19:28,733 The andean long-clawed mouse. 187 00:19:30,870 --> 00:19:35,172 Ninety percent of araucaria seeds fall to the ground, 188 00:19:35,241 --> 00:19:40,044 Where they're greedily devoured by the little mice... 189 00:19:46,886 --> 00:19:53,357 But first they have to get through the tough husk. 190 00:20:04,203 --> 00:20:08,439 Over time the araucaria have come to rely on these mice 191 00:20:08,507 --> 00:20:13,177 And other rodents for their regeneration. 192 00:20:15,648 --> 00:20:18,649 In times of plenty, the long-clawed mice 193 00:20:18,717 --> 00:20:21,452 Eat their fill... 194 00:20:21,520 --> 00:20:25,389 ... Then bury some for later. 195 00:20:31,563 --> 00:20:35,532 If the extra cache doesn't get eaten, 196 00:20:35,535 --> 00:20:43,274 It may germinate into the next generation of giants. 197 00:20:44,477 --> 00:20:47,144 Compared to the rise of the araucaria, 198 00:20:47,146 --> 00:20:50,581 The rise of the andes is a recent event. 199 00:20:50,649 --> 00:20:54,585 ♪ ♪ 200 00:20:59,291 --> 00:21:04,228 It's only 25 million years since huge tectonic forces 201 00:21:04,230 --> 00:21:09,433 Began pushing this land towards the sky. 202 00:21:11,637 --> 00:21:16,474 Many of these peaks are dormant volcanoes -- 203 00:21:17,643 --> 00:21:20,643 Their slopes reddened by iron-rich hematite 204 00:21:20,647 --> 00:21:23,781 From deep within the earth. 205 00:21:23,849 --> 00:21:28,252 Immense ash and debris flows, triggered by eruptions, 206 00:21:28,321 --> 00:21:33,557 Are today sliced through by glacier-fed rivers. 207 00:21:34,260 --> 00:21:37,595 Erosion has chiseled hard igneous rock 208 00:21:37,663 --> 00:21:40,798 Into famous landmarks -- 209 00:21:40,800 --> 00:21:46,136 Such as the three torres del paine. 210 00:21:58,450 --> 00:22:01,751 Predators and their prey have carved their livelihoods 211 00:22:01,821 --> 00:22:06,190 Between the imposing peaks. 212 00:22:08,460 --> 00:22:12,830 The mother puma has left her kittens in a safe place. 213 00:22:12,898 --> 00:22:19,603 Silent and alone, she moves in on the guanaco herd. 214 00:22:22,775 --> 00:22:28,446 Shrubs and rocks offer cover for an ambush. 215 00:22:32,718 --> 00:22:36,720 There are inexperienced youngsters among the herd... 216 00:22:36,723 --> 00:22:41,092 Prime targets. 217 00:22:46,331 --> 00:22:53,537 She must remain downwind and out of sight of the dominant male, 218 00:22:54,207 --> 00:22:57,141 Who stands sentinel over the entire herd 219 00:22:57,209 --> 00:23:01,045 Of females and young. 220 00:23:07,453 --> 00:23:13,124 She will have to approach very carefully. 221 00:23:19,765 --> 00:23:26,604 The essence of stealth, she is almost upon them. 222 00:23:29,909 --> 00:23:36,213 Narrator: The female puma has a target in her sights. 223 00:23:36,949 --> 00:23:44,688 Strong, swirling winds could betray her scent at any moment. 224 00:23:48,527 --> 00:23:52,830 She takes advantage of the mountain's shadow. 225 00:24:01,473 --> 00:24:06,110 But she can't avoid the sunlight completely. 226 00:24:15,387 --> 00:24:19,756 Although strong and agile, she can't outrun guanaco 227 00:24:19,759 --> 00:24:24,829 With top speeds of 30 miles an hour. 228 00:24:24,897 --> 00:24:30,267 Her only option is surprise. 229 00:24:32,505 --> 00:24:36,040 They run... 230 00:24:36,775 --> 00:24:39,843 But it's too late. 231 00:24:42,881 --> 00:24:45,749 Once in the grip of her powerful jaws, 232 00:24:45,817 --> 00:24:50,286 There is no hope of escape. 233 00:25:07,673 --> 00:25:12,109 Her next meal is now assured. 234 00:25:15,847 --> 00:25:21,252 But she'll struggle to hold onto this prize for long. 235 00:25:25,157 --> 00:25:28,559 On these open slopes there's nowhere to hide 236 00:25:28,627 --> 00:25:33,597 From the sharp eyes of aerial scavengers. 237 00:25:36,902 --> 00:25:39,635 It's heavy going as she tries to drag the body 238 00:25:39,705 --> 00:25:45,042 Out of sight of any andean condors. 239 00:25:50,816 --> 00:25:56,520 The mountain offers a cloak of darkness once more. 240 00:26:00,826 --> 00:26:07,765 A patagonian fox, or chilla, is also on the prowl. 241 00:26:09,802 --> 00:26:16,607 Once hidden in the shadows, the puma rips open the flesh. 242 00:26:23,782 --> 00:26:27,751 Dusk is approaching and she'll need to return to her kittens, 243 00:26:27,820 --> 00:26:29,753 But she won't leave the guanaco 244 00:26:29,755 --> 00:26:35,192 Until she's at least eaten its internal organs. 245 00:26:39,898 --> 00:26:42,299 In this punishing environment, 246 00:26:42,300 --> 00:26:45,735 There's no telling when she might eat again... 247 00:26:45,804 --> 00:26:48,305 ... And, without her, the kittens 248 00:26:48,307 --> 00:26:52,443 Stand no chance of surviving. 249 00:26:52,511 --> 00:26:54,311 The heart, liver and lungs 250 00:26:54,380 --> 00:26:57,614 Are the most nutritious parts of a kill. 251 00:26:57,683 --> 00:27:01,785 She won't risk losing these prizes to anyone else. 252 00:27:01,787 --> 00:27:05,956 ♪ ♪ 253 00:27:09,661 --> 00:27:12,829 The chilla may have its eyes on her, 254 00:27:12,898 --> 00:27:18,569 But she has to leave the carcass to rejoin her young. 255 00:27:23,275 --> 00:27:29,613 It's a long way... And it will soon be dark. 256 00:27:39,458 --> 00:27:44,228 Dawn reveals a thief in the pantry. 257 00:27:49,167 --> 00:27:52,636 Chillas mostly hunt small mammals, 258 00:27:52,705 --> 00:27:58,142 But this easy meal is too good to miss. 259 00:27:59,344 --> 00:28:02,046 It's not alone. 260 00:28:13,358 --> 00:28:18,128 Its mate waits nervously in the wings. 261 00:28:22,334 --> 00:28:24,601 Even though they're a monogamous pair... 262 00:28:24,669 --> 00:28:30,007 There's no love lost when it comes to sharing. 263 00:28:32,211 --> 00:28:35,846 ♪ ♪ 264 00:28:35,914 --> 00:28:39,549 As the day warms up, rising thermals 265 00:28:39,618 --> 00:28:46,457 Give andean condors a lift in their endless search for food. 266 00:28:48,293 --> 00:28:50,761 With their 10-foot wingspan 267 00:28:50,829 --> 00:28:56,833 They ride the air currents above the southern cordillera, 268 00:28:56,836 --> 00:29:02,506 Traveling up to 200 miles each day. 269 00:29:14,319 --> 00:29:19,223 This group has spotted the puma's kill. 270 00:29:20,592 --> 00:29:28,398 In this barren land, any leftovers attract like a magnet. 271 00:29:31,202 --> 00:29:33,136 They quickly set to work, 272 00:29:33,205 --> 00:29:37,541 Stripping the flesh from her hard-won meal. 273 00:29:42,815 --> 00:29:48,218 But with so much competition, things soon turn scrappy. 274 00:29:48,220 --> 00:29:50,687 ♪ ♪ 275 00:29:50,755 --> 00:29:54,424 [condors screeching] 276 00:30:11,743 --> 00:30:19,550 Those that eat their fill can barely get off the ground. 277 00:30:31,363 --> 00:30:35,299 ♪ ♪ 278 00:30:37,803 --> 00:30:43,306 Southeast of torres del paine, cool, wet forests 279 00:30:43,375 --> 00:30:49,213 Blanket the foothills of tierra del fuego. 280 00:30:51,884 --> 00:30:55,452 Today it is being seriously impacted 281 00:30:55,520 --> 00:31:00,157 By an animal that shouldn't even be here. 282 00:31:02,494 --> 00:31:05,829 The north american beaver. 283 00:31:05,897 --> 00:31:11,235 In 1946, 50 individuals were brought to tierra del fuego 284 00:31:11,303 --> 00:31:15,505 To create a fur-farming industry. 285 00:31:15,574 --> 00:31:22,079 The scheme failed, but the beavers flourished. 286 00:31:24,182 --> 00:31:28,551 They are extremely industrious engineers. 287 00:31:28,620 --> 00:31:30,420 On a small scale 288 00:31:30,488 --> 00:31:34,057 They mark out their home turf with mud piles... 289 00:31:34,126 --> 00:31:37,794 ... Which they douse with castoreum -- 290 00:31:37,863 --> 00:31:44,368 A powerful-smelling secretion from a gland near their tails. 291 00:31:47,973 --> 00:31:50,874 But their profound impact on the landscape 292 00:31:50,943 --> 00:31:56,313 Extends far beyond these earthen excavations. 293 00:31:58,550 --> 00:32:04,754 Beavers fell trees to dam rivers and create ponds -- 294 00:32:04,757 --> 00:32:10,593 In which they can build their lodges and raise their young, 295 00:32:10,662 --> 00:32:15,032 Safe from predators. 296 00:32:19,604 --> 00:32:22,105 In their north american homeland, 297 00:32:22,174 --> 00:32:24,107 These busy beavers have evolved 298 00:32:24,176 --> 00:32:28,178 In tandem with their environment. 299 00:32:33,585 --> 00:32:41,257 But in tierra del fuego they have become a natural disaster. 300 00:32:41,326 --> 00:32:45,195 Some native species, such as the magellanic woodpecker, 301 00:32:45,197 --> 00:32:48,432 Get a boost -- 302 00:32:50,536 --> 00:32:57,040 Winkling out insect grubs from newly dead or dying wood. 303 00:32:57,876 --> 00:33:00,811 But most species here do not benefit 304 00:33:00,879 --> 00:33:06,683 From the havoc wrought by these rapacious rodents. 305 00:33:15,894 --> 00:33:20,296 Whenever a dam is breached, beavers quickly cut more wood 306 00:33:20,299 --> 00:33:25,802 To plug the gap and maintain the water level. 307 00:33:29,775 --> 00:33:32,542 In north america, their deep ponds 308 00:33:32,610 --> 00:33:37,581 Provide protection from a bear or wolf attack. 309 00:33:40,319 --> 00:33:44,687 Here in tierra del fuego they have no predators... 310 00:33:44,756 --> 00:33:47,657 But still have the urge to build their dams 311 00:33:47,658 --> 00:33:52,194 And maintain their protective moat. 312 00:34:02,474 --> 00:34:04,741 Unfortunately, the trees here 313 00:34:04,810 --> 00:34:10,313 Haven't evolved to cope with being submerged. 314 00:34:12,383 --> 00:34:16,286 Instead, they have become a forest of skeletons, 315 00:34:16,354 --> 00:34:21,124 Scattered across a watery graveyard. 316 00:34:21,192 --> 00:34:23,560 If the invasive beavers remain, 317 00:34:23,562 --> 00:34:25,829 The future of these fragile forests 318 00:34:25,831 --> 00:34:33,703 Here at the end of the world is in terrible jeopardy. 319 00:34:36,274 --> 00:34:40,242 In contrast, the main river in torres del paine 320 00:34:40,245 --> 00:34:44,179 Is in excellent health. 321 00:34:44,249 --> 00:34:48,518 Its waters are home to a pair of chilean torrent ducks, 322 00:34:48,520 --> 00:34:53,523 Trying to raise their family. 323 00:34:54,192 --> 00:34:57,194 Their chicks are barely a week old... 324 00:34:57,262 --> 00:35:01,465 And still looked after by their mother. 325 00:35:04,435 --> 00:35:08,204 The fast-running water is fed by snow and glacier melt, 326 00:35:08,273 --> 00:35:10,206 So it is icy cold. 327 00:35:10,275 --> 00:35:12,775 ♪ ♪ 328 00:35:12,844 --> 00:35:17,681 Undaunted, a chick launches in. 329 00:35:20,318 --> 00:35:23,219 The parents never feed their chicks, 330 00:35:23,222 --> 00:35:29,192 Forcing them to find their own food from the moment they hatch. 331 00:35:31,129 --> 00:35:36,066 The other youngsters don't seem quite so keen. 332 00:35:37,402 --> 00:35:42,272 But they aren't called torrent ducks for nothing. 333 00:35:43,175 --> 00:35:47,577 Strong swimmers, the adults probe the underside of rocks 334 00:35:47,645 --> 00:35:49,112 For the insect larvae 335 00:35:49,181 --> 00:35:54,284 Abundant in these cold well-oxygenated waters. 336 00:36:02,894 --> 00:36:04,460 But the churning rapids 337 00:36:04,463 --> 00:36:08,465 Are a dangerous place for young ducklings. 338 00:36:15,473 --> 00:36:18,541 ♪ ♪ 339 00:36:18,610 --> 00:36:21,744 Narrator: They must learn to feed for themselves, 340 00:36:21,813 --> 00:36:26,183 Despite the powerful current. 341 00:36:35,460 --> 00:36:41,765 Less than a week old, it's time to take the plunge. 342 00:36:51,243 --> 00:36:53,109 Even at their young age, 343 00:36:53,177 --> 00:36:57,680 The three torrent ducklings are doing fine. 344 00:36:57,749 --> 00:37:01,585 Relatively, they are larger than ducklings of other species 345 00:37:01,653 --> 00:37:07,390 And have the extra strength to swim against the current. 346 00:37:15,767 --> 00:37:20,337 But there are limits to what they can handle. 347 00:37:23,508 --> 00:37:27,710 Away from the bank, the current moves at breakneck speed, 348 00:37:27,779 --> 00:37:31,648 Barreling towards a set of cataracts. 349 00:37:36,555 --> 00:37:42,359 Oblivious, the ducklings are heading towards the main flow. 350 00:37:52,771 --> 00:37:55,639 The parents call out to their young... 351 00:37:55,707 --> 00:37:58,508 [duck quacks] 352 00:38:08,319 --> 00:38:09,352 ... Luring the ducklings 353 00:38:09,420 --> 00:38:14,624 Back towards the safety of the riverbank. 354 00:38:15,860 --> 00:38:19,729 Finally, the family is reunited. 355 00:38:19,797 --> 00:38:23,733 ♪ ♪ 356 00:38:32,243 --> 00:38:39,415 The still-downy chicks accept a much-needed cuddle. 357 00:38:39,418 --> 00:38:43,419 ♪ ♪ 358 00:38:48,360 --> 00:38:52,362 Further up one of the valleys in torres del paine, 359 00:38:52,364 --> 00:38:58,467 The mother puma is leading her kittens back to her kill. 360 00:39:04,509 --> 00:39:09,045 Instinctively, they move as silently as possible... 361 00:39:09,114 --> 00:39:15,652 After all, who knows what might be hiding in the long grass? 362 00:39:21,626 --> 00:39:24,527 At the very least, it's good training 363 00:39:24,596 --> 00:39:29,265 For when they themselves start hunting. 364 00:39:31,369 --> 00:39:35,405 Their mother has found the carcass 365 00:39:39,911 --> 00:39:44,247 And there's still some flesh on the bones. 366 00:39:46,451 --> 00:39:53,356 Desperate for food, the kittens can't get there fast enough. 367 00:40:00,165 --> 00:40:03,332 The kittens will rely on their mother's kills 368 00:40:03,401 --> 00:40:10,306 For another couple of months before hunting themselves, 369 00:40:10,375 --> 00:40:15,611 But they'll stay close to her for another year or so. 370 00:40:15,680 --> 00:40:17,781 ♪ ♪ 371 00:40:17,849 --> 00:40:26,289 Well fed, the family takes a moment to relax... And play. 372 00:40:45,576 --> 00:40:49,145 Sparring and wrestling -- interspersed with a clean-up -- 373 00:40:49,147 --> 00:40:51,815 Is good practice, 374 00:40:53,685 --> 00:40:56,853 For a time when teeth, claws and jaws 375 00:40:56,921 --> 00:41:01,391 Will be put to more deadly effect. 376 00:41:19,377 --> 00:41:23,580 This intensely social childhood will soon become 377 00:41:23,648 --> 00:41:31,287 A largely solitary existence -- if they survive. 378 00:41:34,525 --> 00:41:42,732 Even for these big, powerful cats, life hangs by a thread 379 00:41:42,800 --> 00:41:50,073 In this unforgiving and still-volatile mountain range. 380 00:41:51,475 --> 00:41:56,279 ♪ ♪ 381 00:41:56,347 --> 00:42:03,085 In 2015, the calbuco volcano, in central chile, 382 00:42:03,088 --> 00:42:07,056 Exploded into life. 383 00:42:15,567 --> 00:42:21,670 It ejected ash nearly 10 miles into the atmosphere. 384 00:42:30,315 --> 00:42:35,885 And it's just one of nearly 500 active volcanoes 385 00:42:35,953 --> 00:42:40,156 In chile alone. 386 00:42:40,223 --> 00:42:44,392 These belching giants offer stark reminders 387 00:42:44,462 --> 00:42:49,265 Of the violent subterranean forces 388 00:42:49,734 --> 00:42:53,703 Pushing the andes ever higher. 389 00:43:02,347 --> 00:43:07,817 Desolate rivers of ash may kill all in their path. 390 00:43:07,885 --> 00:43:15,758 But even the land entombed here will eventually turn to green. 391 00:43:15,826 --> 00:43:19,028 While these peaks reach for the skies, 392 00:43:19,097 --> 00:43:23,700 The natural world must react and adapt around them. 393 00:43:23,768 --> 00:43:26,736 For it is from this volcanic fire 394 00:43:26,804 --> 00:43:31,707 That the spectacular wildlife of the andes has arisen... 395 00:43:31,710 --> 00:43:35,244 In this untamed patagonia... 396 00:43:35,312 --> 00:43:40,650 The land at the end of the world.