WEBVTT 00:00:08.164 --> 00:00:10.238 Enter a world 00:00:10.832 --> 00:00:13.363 just beyond your perception. 00:00:18.768 --> 00:00:22.105 A world of extraordinary animals, 00:00:23.064 --> 00:00:26.526 with hidden powers, and super senses. 00:00:27.610 --> 00:00:29.738 If you think you know nature... 00:00:32.490 --> 00:00:33.742 think again. 00:00:42.208 --> 00:00:44.168 To survive in extremes, 00:00:45.837 --> 00:00:48.325 you have to push the limits. 00:00:52.367 --> 00:00:54.402 In the Italian Alps, 00:00:56.806 --> 00:00:58.558 a towering dam 00:01:02.062 --> 00:01:05.145 as high as the Golden Gate Bridge. 00:01:08.568 --> 00:01:10.872 It holds a hidden treasure... 00:01:13.864 --> 00:01:15.416 salt. 00:01:16.011 --> 00:01:18.037 Pouring from its wall. 00:01:20.121 --> 00:01:21.911 It's so rare up here, 00:01:22.332 --> 00:01:24.793 ibex risk everything to reach it. 00:01:33.093 --> 00:01:35.548 Scaling these near-vertical walls calls 00:01:35.572 --> 00:01:37.918 on incredible climbing skills. 00:01:44.418 --> 00:01:46.962 These natural-born mountaineers 00:01:46.986 --> 00:01:49.543 make it look like a walk in the park. 00:01:52.237 --> 00:01:54.668 But imagine what it's like for a kid. 00:01:57.413 --> 00:01:58.908 Going up there 00:02:00.911 --> 00:02:03.080 for the very first time. 00:02:11.855 --> 00:02:15.534 He has no choice but to follow his mother. 00:02:17.428 --> 00:02:20.011 A fall would mean certain death. 00:02:26.813 --> 00:02:28.773 But step by step, 00:02:29.399 --> 00:02:31.776 he discovers he has an amazing grip. 00:02:33.570 --> 00:02:35.380 The higher he goes, 00:02:35.405 --> 00:02:37.240 the more vertical the face. 00:02:43.371 --> 00:02:47.292 Now, his survival depends on his innate superpower. 00:02:52.172 --> 00:02:55.842 Soft, rubbery soles mold around even the tiniest ridges. 00:02:59.012 --> 00:03:01.917 Locking them inside the hard edge of the hoof. 00:03:09.076 --> 00:03:10.553 He balances. 00:03:12.400 --> 00:03:14.788 Every step on a knife edge. 00:03:19.574 --> 00:03:22.585 It's exhausting work for one so young. 00:03:40.011 --> 00:03:43.349 Just in time, his mother notices. 00:03:47.602 --> 00:03:50.239 She gives him a chance to recharge. 00:03:53.566 --> 00:03:55.318 A 5-minute power nap. 00:04:11.376 --> 00:04:13.800 150 feet up, 00:04:16.089 --> 00:04:19.738 finally, he reaches his goal. 00:04:23.346 --> 00:04:28.368 Twenty percent of concrete contains salt and water 00:04:28.393 --> 00:04:32.261 seeping through the dam brings it to the surface. 00:04:34.023 --> 00:04:36.312 It may not look like much, 00:04:36.336 --> 00:04:38.861 but this mineral lick is crucial 00:04:38.886 --> 00:04:41.183 for the kid to grow up strong. 00:04:45.702 --> 00:04:48.079 Muscles and nerves replenished, 00:04:49.434 --> 00:04:51.784 his epic ascent is complete. 00:04:56.212 --> 00:04:57.976 Death-defying missions like this 00:04:58.000 --> 00:05:00.550 are a vital part of many animals' lives, 00:05:03.720 --> 00:05:05.716 and we're only just discovering 00:05:05.740 --> 00:05:08.599 the wondrous ways in which they succeed. 00:05:28.244 --> 00:05:30.747 The dunes of northeast Brazil. 00:05:32.665 --> 00:05:35.293 An area larger than Los Angeles. 00:05:37.962 --> 00:05:40.757 Scorched by the fierce equatorial sun. 00:05:49.807 --> 00:05:51.726 Many who try to cross 00:05:52.852 --> 00:05:53.853 never make it. 00:05:57.982 --> 00:05:59.484 But there are opportunities... 00:06:00.234 --> 00:06:02.111 you just need to find them. 00:06:07.700 --> 00:06:10.328 After five months in suspended animation, 00:06:11.162 --> 00:06:12.538 without food or water, 00:06:15.500 --> 00:06:17.210 a Brazilian slider, 00:06:18.294 --> 00:06:21.929 a normally aquatic turtle, emerges. 00:06:25.256 --> 00:06:27.756 Something has awakened her. 00:06:30.640 --> 00:06:34.695 Her acute sense of smell has detected a change in the humidity, 00:06:35.978 --> 00:06:38.015 her only hope of survival 00:06:38.648 --> 00:06:39.992 is water. 00:06:43.136 --> 00:06:44.710 But to reach it, 00:06:45.437 --> 00:06:48.592 she must attempt the impossible. 00:06:51.603 --> 00:06:53.507 Traveling for days 00:06:53.884 --> 00:06:56.718 across sunbaked sands. 00:07:02.948 --> 00:07:04.710 Every moment exposed 00:07:04.735 --> 00:07:06.759 means hydration lost. 00:07:10.918 --> 00:07:12.826 And as the wind picks up, 00:07:13.912 --> 00:07:16.343 she loses the scent of water.... 00:07:21.984 --> 00:07:25.132 So, which way now? 00:07:30.616 --> 00:07:32.390 In this hostile landscape, 00:07:33.077 --> 00:07:34.765 she'll soon dry up. 00:07:37.623 --> 00:07:39.984 But the sun that threatens to cook her 00:07:40.501 --> 00:07:42.758 is also her guiding light. 00:07:46.310 --> 00:07:48.695 Using its position as a compass, 00:07:49.807 --> 00:07:51.890 she keeps on her course. 00:08:04.809 --> 00:08:07.226 She's almost there... 00:08:08.070 --> 00:08:09.844 Just in time. 00:08:13.727 --> 00:08:15.867 When the rains arrive, 00:08:16.677 --> 00:08:19.664 a magical transformation begins. 00:08:24.170 --> 00:08:27.882 In most dunes, water quickly drains through the sand.... 00:08:34.347 --> 00:08:38.440 But here, a layer of solid rock beneath 00:08:39.143 --> 00:08:40.853 blocks the water's path, 00:08:42.146 --> 00:08:45.268 allowing thousands of pools to form. 00:08:49.230 --> 00:08:51.494 Just one last obstacle. 00:09:11.318 --> 00:09:14.800 Now, it's downhill all the way. 00:09:18.766 --> 00:09:21.737 Time to do what a slider does best. 00:09:43.207 --> 00:09:45.836 A crystal-clear oasis. 00:09:52.829 --> 00:09:55.573 These ephemeral pools bring food. 00:10:00.516 --> 00:10:03.011 And the chance to meet a mate... 00:10:07.148 --> 00:10:09.273 before the water vanishes 00:10:09.297 --> 00:10:11.736 and the scorched desert returns. 00:10:21.419 --> 00:10:24.760 Incredible journeys are happening across the planet. 00:10:26.417 --> 00:10:28.002 But they're often overlooked. 00:10:32.594 --> 00:10:34.108 The city of London. 00:10:35.561 --> 00:10:38.920 A confusing man-made maze. 00:10:41.836 --> 00:10:44.388 But hidden away behind its walls, 00:10:47.188 --> 00:10:48.581 there are animals 00:10:48.606 --> 00:10:51.764 who've learned to navigate this urban jungle. 00:10:54.695 --> 00:10:59.075 This buff-tailed bumblebee is about to embark on a royal mission... 00:11:01.535 --> 00:11:03.746 to find food for the queen's larvae 00:11:04.705 --> 00:11:07.208 and secure the future of the colony. 00:11:14.561 --> 00:11:16.604 Easier said than done. 00:11:18.969 --> 00:11:22.848 Confusing concrete corridors could be hard to navigate. 00:11:26.060 --> 00:11:27.311 But not for her. 00:11:29.814 --> 00:11:31.565 Like a London cab driver, 00:11:32.066 --> 00:11:33.567 she's got the knowledge. 00:11:35.178 --> 00:11:37.127 She knows the landmarks to build 00:11:37.151 --> 00:11:39.576 a mental map of the streets. 00:11:39.990 --> 00:11:42.660 Though some things in this city never stay put. 00:11:50.501 --> 00:11:54.422 But it takes more than a little traffic to stop this busy bee. 00:11:56.632 --> 00:12:00.469 She travels up to seven miles on her daily commute in search of nectar. 00:12:02.930 --> 00:12:05.430 And this is where she finds it: 00:12:06.559 --> 00:12:10.396 one of three million gardens that make up a quarter of the city. 00:12:12.857 --> 00:12:14.984 And it's in full bloom. 00:12:18.904 --> 00:12:21.518 Thousands of lenses in her eyes 00:12:21.542 --> 00:12:23.117 detect the shape and color 00:12:23.200 --> 00:12:24.535 of nectar-rich flowers. 00:12:26.996 --> 00:12:28.539 And ultraviolet vision, 00:12:29.373 --> 00:12:31.792 reveals secret patterns in the petals. 00:12:37.089 --> 00:12:39.008 But another bee's already been here. 00:12:40.926 --> 00:12:43.053 So, to target untapped plants, 00:12:44.555 --> 00:12:47.821 she tunes into an invisible force. 00:12:50.730 --> 00:12:52.179 As bees fly, they gain a positive charge 00:12:52.203 --> 00:12:54.688 from the atmosphere, 00:12:58.360 --> 00:12:59.696 but flowers 00:13:00.446 --> 00:13:01.977 are negatively charged. 00:13:03.982 --> 00:13:06.641 So, when a positive bee visits a negative flower, 00:13:06.666 --> 00:13:09.336 it briefly alters the electric field. 00:13:12.272 --> 00:13:15.711 Hairs on her legs detect these changes. 00:13:19.298 --> 00:13:22.774 Ensuring she strikes gold every time. 00:13:26.764 --> 00:13:29.600 But her journey has just begun. 00:13:37.584 --> 00:13:40.461 She's called a worker bee for a reason. 00:13:43.209 --> 00:13:47.063 She'll visit up to 5,000 flowers a day. 00:13:51.372 --> 00:13:54.352 Then, remembering every twist and turn, 00:13:55.334 --> 00:13:58.546 she carries her own body weight in pollen 00:13:58.571 --> 00:14:00.864 and nectar, all the way back to the nest. 00:14:03.592 --> 00:14:07.683 A royal delivery for queen and colony. 00:14:13.016 --> 00:14:16.922 While many animals undertake a testing daily commute, 00:14:20.234 --> 00:14:23.445 others embark on epic migrations 00:14:24.864 --> 00:14:27.725 that take months to complete. 00:14:30.632 --> 00:14:32.990 Winter is coming. 00:14:34.539 --> 00:14:37.006 Days are getting shorter. 00:14:38.750 --> 00:14:40.991 Food is running out. 00:14:49.889 --> 00:14:53.236 Bad news for a young humpback whale. 00:15:04.445 --> 00:15:07.658 He arrived in Antarctica with his mother, 00:15:09.175 --> 00:15:13.892 but now he's left all alone in this vast ocean. 00:15:16.874 --> 00:15:19.335 And soon he must embark 00:15:19.567 --> 00:15:23.589 on one of the longest migrations of any mammal. 00:15:26.050 --> 00:15:28.657 Swimming 80 miles a day 00:15:28.681 --> 00:15:32.114 to reach warm waters further north. 00:15:34.880 --> 00:15:37.603 But how to navigate 3,000 miles 00:15:37.627 --> 00:15:39.622 through a featureless ocean, 00:15:39.647 --> 00:15:43.216 with strong currents that could push him off-course? 00:15:46.896 --> 00:15:48.724 To stay on-track, 00:15:48.855 --> 00:15:53.083 he tunes into a mysterious planetary phenomenon. 00:16:05.349 --> 00:16:09.919 As charged particles from the sun hit the Earth's atmosphere, 00:16:10.597 --> 00:16:13.981 they illuminate the southern skies... 00:16:17.929 --> 00:16:21.762 but there's more to this heavenly display than meets the eye. 00:16:23.107 --> 00:16:28.286 The Aurora Australis reveals Earth's magnetic field, 00:16:29.031 --> 00:16:33.192 an invisible force scientists believe whales can sense 00:16:33.242 --> 00:16:36.302 using magnetic particles in their brains. 00:16:40.763 --> 00:16:43.329 This internal compass keeps 00:16:43.353 --> 00:16:45.839 the humpback on course, 00:16:45.864 --> 00:16:48.090 accurate to one degree. 00:16:52.396 --> 00:16:55.259 But it leads him out into the open ocean 00:16:55.669 --> 00:16:57.658 where the fish and crustaceans he eats 00:16:57.683 --> 00:16:59.646 are hard to find. 00:17:03.058 --> 00:17:06.294 It's been weeks since he last ate. 00:17:11.864 --> 00:17:13.073 But then... 00:17:15.409 --> 00:17:16.994 ...he hears something. 00:17:22.583 --> 00:17:25.085 Using his body like a giant microphone, 00:17:26.336 --> 00:17:29.173 sound vibrations rush through his skeleton, 00:17:30.340 --> 00:17:31.759 straight to his head. 00:17:34.344 --> 00:17:37.074 The welcome calls of other whales, 00:17:37.098 --> 00:17:39.054 hundreds of miles away. 00:17:44.813 --> 00:17:47.608 He homes in on a growing barrage of sound. 00:17:51.820 --> 00:17:55.617 Finally, five weeks after leaving Antarctica, 00:17:56.139 --> 00:18:00.094 he joins hundreds with other whales for a monster feast. 00:18:06.085 --> 00:18:09.171 One of the largest humpback gatherings on the planets, 00:18:10.547 --> 00:18:12.216 there are hundreds of them. 00:18:19.181 --> 00:18:24.019 This annual assembly has only recently been discovered. 00:18:31.485 --> 00:18:34.046 Three miles off the coast of Africa, 00:18:34.071 --> 00:18:36.115 strong currents create an upwelling 00:18:36.240 --> 00:18:40.119 of nutrients and an explosion of life. 00:18:44.540 --> 00:18:46.125 In a single mouthful, 00:18:46.750 --> 00:18:49.378 he swallows thousands of fish and shrimp, 00:18:51.922 --> 00:18:54.299 150,000 calories, 00:18:55.551 --> 00:18:59.221 that's the equivalent of 600 chocolate bars. 00:19:02.850 --> 00:19:04.184 Once fully fed, 00:19:05.144 --> 00:19:06.687 he must leave his friends 00:19:07.563 --> 00:19:09.648 and head off alone 00:19:10.589 --> 00:19:14.409 to complete his epic journey north. 00:19:20.468 --> 00:19:24.542 There are animals with the power to travel right across the globe, 00:19:25.455 --> 00:19:30.294 but the most intrepid of all is a creature you'd never expect. 00:19:36.425 --> 00:19:38.440 The British countryside... 00:19:43.098 --> 00:19:46.226 ...home to a baby cupboard spider, 00:19:52.566 --> 00:19:55.360 no bigger than a pinhead. 00:20:00.324 --> 00:20:03.994 She's got about 200 brothers and sisters. 00:20:11.251 --> 00:20:16.715 And her siblings have some truly appalling table manners. 00:20:18.967 --> 00:20:20.510 These spiderlings 00:20:21.678 --> 00:20:22.888 are cannibals. 00:20:39.529 --> 00:20:43.742 This is one family meal you don't want to hang around for. 00:20:49.498 --> 00:20:52.209 Better get away as fast 00:20:52.918 --> 00:20:54.378 and as far as she can. 00:21:03.178 --> 00:21:04.388 The trouble is 00:21:05.055 --> 00:21:07.849 her siblings have the same plan. 00:21:15.023 --> 00:21:17.985 And she just ran out of road. 00:21:21.738 --> 00:21:23.991 But when it comes to great escapes, 00:21:24.658 --> 00:21:27.786 this spider has an extraordinary skill. 00:21:32.874 --> 00:21:36.336 She fires out negatively charged silk thread 00:21:37.796 --> 00:21:40.215 into the positively charged atmosphere. 00:21:44.803 --> 00:21:47.099 Opposites forces attract, 00:21:49.891 --> 00:21:51.506 pulling her up, 00:21:53.520 --> 00:21:54.982 up 00:21:56.356 --> 00:21:57.810 and away. 00:22:01.862 --> 00:22:03.196 Heading high, 00:22:04.948 --> 00:22:06.700 riding the wind, 00:22:08.201 --> 00:22:10.645 even cruising the jet stream, 00:22:12.388 --> 00:22:15.435 she can travel for thousands of miles. 00:22:22.424 --> 00:22:24.137 By ballooning, 00:22:24.384 --> 00:22:27.645 they've colonized every corner of the Earth. 00:22:32.768 --> 00:22:34.747 At the mercy of the wind, 00:22:35.437 --> 00:22:39.325 she has no control over where she touches down. 00:22:45.572 --> 00:22:48.033 But weighing less than a grain of sand, 00:22:48.918 --> 00:22:51.439 she doesn't even break the surface. 00:23:01.595 --> 00:23:05.785 She just deploys her magical silk once more, 00:23:08.387 --> 00:23:11.583 and kitesurfs to safety. 00:23:17.458 --> 00:23:21.137 A new place she can call home. 00:23:31.915 --> 00:23:35.648 One animal's journey is all about timing. 00:23:36.790 --> 00:23:39.617 Waiting for the planets to align 00:23:40.252 --> 00:23:42.754 so it can transcend from one world 00:23:44.339 --> 00:23:45.757 to another. 00:23:51.184 --> 00:23:54.177 A three-foot-long epaulette shark 00:23:55.725 --> 00:23:58.668 may not seem the most adventurous traveler.... 00:24:03.108 --> 00:24:06.486 He rarely even strays far from his patch of reef. 00:24:16.155 --> 00:24:18.826 But on some special nights, 00:24:20.845 --> 00:24:25.639 heavenly bodies turn his world upside down. 00:24:28.508 --> 00:24:30.051 At full moon, 00:24:30.802 --> 00:24:35.182 a spring tide pulls billions of gallons of water off the reef, 00:24:43.482 --> 00:24:45.250 stranding creatures 00:24:45.275 --> 00:24:48.653 in a maze of tidal pools. 00:24:51.781 --> 00:24:53.450 Or worse. 00:24:58.723 --> 00:25:00.418 Left high and dry, 00:25:00.749 --> 00:25:03.497 a fish out of water soon suffocates. 00:25:12.469 --> 00:25:13.856 Unless... 00:25:14.513 --> 00:25:16.207 it's a super fish. 00:25:19.184 --> 00:25:21.325 A walking shark. 00:25:25.440 --> 00:25:28.301 And he's not just saving his skin, 00:25:30.487 --> 00:25:32.762 he's on the prowl. 00:25:34.736 --> 00:25:37.965 Heading towards rich hunting pools 00:25:40.789 --> 00:25:43.911 full of prey trapped by the tide. 00:25:47.170 --> 00:25:50.507 Forcing a jet of water through his muscular gills, 00:25:51.049 --> 00:25:53.885 he hoovers up his cornered victims. 00:26:15.073 --> 00:26:17.409 But he's caught in a race against time. 00:26:31.506 --> 00:26:34.968 Oxygen levels in the pool are falling fast. 00:26:39.055 --> 00:26:41.391 Pretty soon, he'll run out of energy. 00:26:44.269 --> 00:26:46.354 With an hour till the tide returns, 00:26:47.272 --> 00:26:48.732 he's close to death. 00:26:57.282 --> 00:27:00.219 But these extreme conditions trigger 00:27:00.243 --> 00:27:03.622 an extraordinary physiological response. 00:27:06.147 --> 00:27:08.277 Slowing his breathing, 00:27:09.461 --> 00:27:11.212 reducing his heart rate, 00:27:13.076 --> 00:27:15.949 even shutting down part of his brain. 00:27:18.136 --> 00:27:21.806 He enters a self-induced coma.... 00:27:27.520 --> 00:27:29.402 One last breath, 00:27:29.981 --> 00:27:33.160 and he can survive for an hour. 00:27:39.324 --> 00:27:41.004 But after that, 00:27:41.367 --> 00:27:43.159 his time is up. 00:27:47.248 --> 00:27:50.168 Finally, the tide turns, 00:27:52.441 --> 00:27:55.761 immersing him in oxygen-rich waters. 00:28:02.013 --> 00:28:04.057 A miraculous resurrection. 00:28:12.649 --> 00:28:15.450 Perhaps the most impossible journeys of all 00:28:16.000 --> 00:28:18.965 are made by those who can't even move. 00:28:24.327 --> 00:28:26.780 The secret to how plants spread 00:28:28.540 --> 00:28:30.592 is seeds. 00:28:34.421 --> 00:28:36.798 All the ingredients for new life, 00:28:37.882 --> 00:28:39.764 packed and ready to go. 00:28:41.720 --> 00:28:44.180 Some have evolved explosive mechanisms... 00:28:46.391 --> 00:28:48.685 ...others harness the wind. 00:28:53.679 --> 00:28:56.085 But one cunning plant 00:28:56.413 --> 00:28:59.077 simply makes someone else do all the legwork. 00:29:04.117 --> 00:29:07.912 A female dung beetle on the African plains. 00:29:11.592 --> 00:29:15.521 There's only one thing that will make her go to extraordinary lengths: 00:29:21.801 --> 00:29:25.939 the sweet scent of antelope droppings. 00:29:27.599 --> 00:29:29.790 Perfect food for her young. 00:29:32.687 --> 00:29:34.704 Using her antennae, 00:29:36.608 --> 00:29:39.689 she selects the juiciest morsel. 00:29:42.113 --> 00:29:43.490 It smells like it, 00:29:48.203 --> 00:29:50.028 it looks like it, 00:29:55.376 --> 00:29:58.059 it even rolls like it. 00:30:00.877 --> 00:30:03.926 But this poop is an imposter. 00:30:06.638 --> 00:30:09.145 It's so convincingly like the real thing; 00:30:09.682 --> 00:30:11.643 she's prepared to fight for it. 00:30:31.579 --> 00:30:35.047 Victorious, she heads off to stash her prize away 00:30:35.072 --> 00:30:36.960 from the competition. 00:30:41.089 --> 00:30:43.977 But she's been duped. 00:30:45.802 --> 00:30:48.203 She thinks she's hiding it, 00:30:49.889 --> 00:30:52.820 but really she's planting it. 00:30:56.563 --> 00:30:58.606 She's nothing more than a vehicle 00:30:59.649 --> 00:31:01.720 in the incredible adventure 00:31:02.277 --> 00:31:04.752 of the cunning elephant reed. 00:31:15.164 --> 00:31:18.871 One animal traveler takes the journey of a lifetime, 00:31:19.836 --> 00:31:22.922 just to get back to where it started. 00:31:29.059 --> 00:31:30.661 This nymph 00:31:30.997 --> 00:31:34.685 has been hanging out in a Hungarian riverbed. 00:31:36.936 --> 00:31:39.060 For the last three years, 00:31:39.772 --> 00:31:41.232 she's been building strength 00:31:42.066 --> 00:31:44.539 for an incredible journey. 00:31:47.155 --> 00:31:49.898 When the water temperature is just right, 00:31:56.002 --> 00:31:58.260 she departs one world 00:31:59.626 --> 00:32:02.869 to enter another. 00:32:06.752 --> 00:32:09.994 It's a magical transformation. 00:32:14.140 --> 00:32:16.525 A mayfly is born. 00:32:17.602 --> 00:32:20.855 And not just one... 00:32:21.564 --> 00:32:23.942 ...thousands emerge every minute. 00:32:40.291 --> 00:32:42.721 Though many are eaten by predators, 00:32:45.157 --> 00:32:47.455 there is safety in numbers. 00:32:51.719 --> 00:32:55.139 But numbers soon become her greatest challenge. 00:32:57.225 --> 00:33:00.214 She's mobbed by an army of male suitors. 00:33:06.526 --> 00:33:10.237 Weighed down with 8,000 fertilized eggs, 00:33:10.989 --> 00:33:12.657 she needs to lay soon. 00:33:16.202 --> 00:33:19.163 This is the best place for her young to grow 00:33:20.915 --> 00:33:22.455 but if she laid here, 00:33:22.580 --> 00:33:25.048 the current would carry her eggs away. 00:33:28.599 --> 00:33:31.899 She has to make it further upstream. 00:33:42.311 --> 00:33:46.058 Her polarized vision picks up light reflecting off the river. 00:33:47.014 --> 00:33:51.081 A shimmering path leading to her final destination. 00:33:54.154 --> 00:33:57.675 In just a few hours, she travels six miles. 00:34:01.289 --> 00:34:05.332 Close to death, she reaches the same stretch of river 00:34:05.418 --> 00:34:07.086 where her life began. 00:34:09.922 --> 00:34:12.133 The perfect place to lay 00:34:13.259 --> 00:34:15.261 so her eggs can drift downstream 00:34:15.970 --> 00:34:18.514 and hatch in exactly the same spot 00:34:19.057 --> 00:34:20.266 where she grew up. 00:34:24.687 --> 00:34:26.296 As her life ends, 00:34:27.064 --> 00:34:28.951 others begin. 00:34:32.653 --> 00:34:35.364 Now, her offspring start their own voyage 00:34:37.158 --> 00:34:40.780 all the way back to where it began. 00:34:52.381 --> 00:34:54.623 When starting a new journey, 00:34:55.760 --> 00:34:57.845 sometimes it's the first step 00:34:59.597 --> 00:35:02.308 that's the most terrifying of all. 00:35:06.646 --> 00:35:09.445 After 20 hours trying to break free... 00:35:19.369 --> 00:35:22.765 ...a guillemot chick's first view of the world is this... 00:35:33.714 --> 00:35:36.759 1,000 feet up. 00:35:39.345 --> 00:35:42.390 It's like peering off the top of the Empire State Building. 00:35:46.727 --> 00:35:49.730 But why be born in such a dangerous place? 00:35:53.192 --> 00:35:57.280 This Icelandic cliff is inaccessible to most predators. 00:35:58.364 --> 00:36:00.116 A safe haven to grow up in. 00:36:01.284 --> 00:36:03.219 But in just three weeks, 00:36:03.244 --> 00:36:05.204 it will be time to leave the nest. 00:36:06.372 --> 00:36:09.894 And this chick will face a life-or-death decision. 00:36:14.505 --> 00:36:17.258 Her bond with her parents is already strong. 00:36:19.510 --> 00:36:22.221 It started long before she even hatched. 00:36:24.035 --> 00:36:27.332 Responding to her first gentle calls, 00:36:28.519 --> 00:36:30.730 her parents talked to her... 00:36:30.865 --> 00:36:32.533 ...inside the egg. 00:36:38.029 --> 00:36:40.740 These early conversations 00:36:42.074 --> 00:36:45.296 ensured the newborn already recognizes 00:36:45.320 --> 00:36:46.816 and trusts Mom and Dad. 00:36:55.588 --> 00:36:58.816 Her parents work tirelessly to feed her up 00:36:58.841 --> 00:37:01.052 in preparation for the journey ahead. 00:37:05.963 --> 00:37:07.898 But as the weeks pass, 00:37:08.017 --> 00:37:11.020 it gets harder to satisfy her growing appetite. 00:37:23.115 --> 00:37:26.316 And now this clifftop home that protected her 00:37:26.953 --> 00:37:28.496 has been discovered... 00:37:30.957 --> 00:37:32.375 by ravens. 00:37:35.544 --> 00:37:38.297 Predators kill up to 70 percent of chicks 00:37:39.966 --> 00:37:43.219 and parents are almost defenseless against the threat. 00:37:46.138 --> 00:37:48.891 This time, the chick gets lucky. 00:37:52.144 --> 00:37:55.231 But she needs to leave before the ravens return. 00:38:01.195 --> 00:38:02.604 The problem is, 00:38:03.281 --> 00:38:04.991 without adult feathers, 00:38:05.700 --> 00:38:07.081 she can't fly. 00:38:15.710 --> 00:38:20.010 Her father encourages her to jump. 00:38:23.384 --> 00:38:26.929 It's a vertical drop of more than one-hundred stories.... 00:38:37.648 --> 00:38:40.392 Trusting him completely, 00:38:40.693 --> 00:38:43.654 the chick takes a leap of faith.... 00:39:06.384 --> 00:39:09.262 The chicks flapping seems futile. 00:39:15.603 --> 00:39:18.856 But it's just enough to slow her down 00:39:20.316 --> 00:39:23.110 and steer her away from the jagged rocks. 00:39:49.345 --> 00:39:52.264 Her downy feathers soften the landing. 00:39:55.226 --> 00:39:59.230 This seemingly impossible journey is vital to her survival. 00:40:01.273 --> 00:40:05.403 Now out at sea, Dad can lead her to food. 00:40:11.409 --> 00:40:13.411 She will face many more obstacles, 00:40:14.995 --> 00:40:16.997 but with extraordinary bravery, 00:40:17.998 --> 00:40:19.125 she can make it through. 00:40:36.142 --> 00:40:38.853 When animals can tap into remarkable senses 00:40:41.021 --> 00:40:42.773 and supernatural skills... 00:40:47.027 --> 00:40:48.362 crossing the globe, 00:40:50.739 --> 00:40:52.700 even moving between worlds 00:40:54.368 --> 00:40:55.369 to find a mate, 00:40:57.288 --> 00:40:58.330 safety 00:40:59.081 --> 00:41:00.249 and food, 00:41:01.333 --> 00:41:04.170 they become truly unstoppable. 00:41:05.713 --> 00:41:07.715 If you think you know nature, 00:41:09.717 --> 00:41:11.010 think again.