1 00:00:09,360 --> 00:00:13,800 Far away, cut off by vast oceans... 2 00:00:17,240 --> 00:00:20,320 ..lie Earth's tropical islands. 3 00:00:25,440 --> 00:00:29,040 Home to remarkable animal castaways... 4 00:00:31,000 --> 00:00:33,120 ..that have evolved in isolation... 5 00:00:37,640 --> 00:00:39,200 ..and human cultures that have 6 00:00:39,200 --> 00:00:41,360 adapted in extraordinary ways. 7 00:00:44,560 --> 00:00:47,280 From the jungles of Borneo, 8 00:00:47,280 --> 00:00:49,240 with their staggering 9 00:00:49,240 --> 00:00:51,200 wild diversity... 10 00:00:57,800 --> 00:01:01,680 ..to Hawaii, the most remote island chain, 11 00:01:01,680 --> 00:01:05,000 colonised by only the hardiest pioneers. 12 00:01:08,480 --> 00:01:10,680 And Madagascar, 13 00:01:10,680 --> 00:01:12,560 the oldest island of all, 14 00:01:12,560 --> 00:01:15,760 where time has given rise 15 00:01:15,760 --> 00:01:18,160 to thousands of unique species. 16 00:01:19,720 --> 00:01:22,240 ANIMALS CALL 17 00:01:26,920 --> 00:01:29,400 These tropical islands 18 00:01:29,400 --> 00:01:31,720 have developed into astonishing 19 00:01:31,720 --> 00:01:33,560 and unique worlds... 20 00:01:36,440 --> 00:01:39,000 ..cradling precious life 21 00:01:39,000 --> 00:01:42,360 found nowhere else on Earth. 22 00:02:05,920 --> 00:02:08,120 In the heart of South East Asia... 23 00:02:10,400 --> 00:02:12,000 ..lies the tropical island 24 00:02:12,000 --> 00:02:13,600 of Borneo. 25 00:02:16,080 --> 00:02:19,000 Twice the size of the British Isles, 26 00:02:19,000 --> 00:02:21,360 it's the world's third largest island. 27 00:02:24,200 --> 00:02:27,200 Its wide variety of habitats 28 00:02:27,200 --> 00:02:31,560 is home to over 60,000 species of animals 29 00:02:31,560 --> 00:02:33,280 and plants. 30 00:02:34,760 --> 00:02:36,760 Possibly the greatest diversity 31 00:02:36,760 --> 00:02:39,720 of life of any island. 32 00:02:57,360 --> 00:02:59,800 Borneo's shoreline is fringed by 33 00:02:59,800 --> 00:03:01,320 a unique habitat. 34 00:03:05,240 --> 00:03:08,000 A vast flooded forest, 35 00:03:08,000 --> 00:03:10,600 criss-crossed by a network of rivers. 36 00:03:16,800 --> 00:03:19,480 Within this waterlogged jungle, 37 00:03:19,480 --> 00:03:22,640 an extraordinary creature has evolved. 38 00:03:32,480 --> 00:03:35,920 The proboscis monkey. 39 00:03:38,920 --> 00:03:40,600 This male's enlarged nose 40 00:03:40,600 --> 00:03:42,800 serves one key purpose. 41 00:03:46,120 --> 00:03:47,880 To attract a mate. 42 00:03:51,480 --> 00:03:53,760 And his supersized snout... 43 00:03:55,360 --> 00:03:59,680 ..has secured him a harem of adoring females... 44 00:04:09,200 --> 00:04:11,320 ..and their offspring. 45 00:04:17,000 --> 00:04:20,000 It will take this baby seven long years 46 00:04:20,000 --> 00:04:22,000 to grow a nose to rival his father's. 47 00:04:27,120 --> 00:04:28,880 But for these monkeys... 48 00:04:29,880 --> 00:04:31,680 ..it is their pot bellies 49 00:04:31,680 --> 00:04:34,000 that are key to their survival. 50 00:04:37,920 --> 00:04:40,240 There is precious little nutrition 51 00:04:40,240 --> 00:04:42,000 to be found in the bitter leaves of 52 00:04:42,000 --> 00:04:44,360 these flooded forests. 53 00:04:46,040 --> 00:04:49,760 Proboscis have evolved an enlarged gut to extract 54 00:04:49,760 --> 00:04:51,640 any goodness there is. 55 00:04:56,720 --> 00:04:58,760 Still, only the youngest leaves 56 00:04:58,760 --> 00:05:00,400 have enough nutrition 57 00:05:00,400 --> 00:05:01,840 to be worth eating... 58 00:05:05,560 --> 00:05:07,920 ..so the male must lead his troop 59 00:05:07,920 --> 00:05:09,720 up to a mile a day 60 00:05:09,720 --> 00:05:12,120 in search of fresh growth. 61 00:05:31,200 --> 00:05:33,120 But their route is often blocked... 62 00:05:35,800 --> 00:05:38,400 ..by one of the many rivers that cut through the forest. 63 00:05:42,240 --> 00:05:44,880 Patrolled by giant predators... 64 00:05:50,160 --> 00:05:52,680 ..growing to more than five metres long 65 00:05:52,680 --> 00:05:55,680 and weighing up to a tonne. 66 00:05:57,120 --> 00:05:59,120 The saltwater crocodile. 67 00:06:01,920 --> 00:06:05,440 To reach the young, juicy leaves on the other side, 68 00:06:05,440 --> 00:06:08,240 the group will have to cross... 69 00:06:09,800 --> 00:06:12,120 ..but the male is hesitant. 70 00:06:22,080 --> 00:06:24,520 Instead, it's the alpha female 71 00:06:24,520 --> 00:06:26,360 who takes the lead. 72 00:06:45,400 --> 00:06:47,640 LOUD SPLASH 73 00:07:00,280 --> 00:07:02,720 The rest of the troop quickly follow. 74 00:07:08,160 --> 00:07:10,200 LOUD SPLASHES 75 00:07:25,440 --> 00:07:27,360 Sounds of their splashes carry 76 00:07:27,360 --> 00:07:29,520 over 200 metres through the water... 77 00:07:32,320 --> 00:07:34,760 ..and can draw unwanted attention. 78 00:07:43,080 --> 00:07:46,840 But unlike most other monkeys, 79 00:07:46,840 --> 00:07:49,480 proboscis are excellent swimmers. 80 00:07:49,480 --> 00:07:51,640 To survive here, 81 00:07:51,640 --> 00:07:54,240 they have evolved webbed feet. 82 00:08:03,640 --> 00:08:06,880 Finally, the reluctant male 83 00:08:06,880 --> 00:08:08,400 makes his move. 84 00:08:18,880 --> 00:08:20,520 LOUD SPLASH 85 00:08:23,560 --> 00:08:25,200 SQUEALING 86 00:08:25,200 --> 00:08:28,240 But a mother and baby have been left behind. 87 00:08:40,640 --> 00:08:43,640 The baby must cling on for dear life. 88 00:08:51,360 --> 00:08:52,960 LOUD SPLASH 89 00:09:26,880 --> 00:09:29,440 MONKEYS SQUEAL 90 00:09:45,800 --> 00:09:48,040 This time, the whole family 91 00:09:48,040 --> 00:09:49,240 have made it. 92 00:09:53,520 --> 00:09:55,880 Even the most vulnerable. 93 00:10:02,680 --> 00:10:05,080 At last, they can feed on 94 00:10:05,080 --> 00:10:07,160 the succulent fresh leaves. 95 00:10:13,080 --> 00:10:14,680 With its unique adaptations 96 00:10:14,680 --> 00:10:16,680 for surviving in these flooded forests... 97 00:10:19,920 --> 00:10:23,680 ..the proboscis monkey is just one of over 6,000 species 98 00:10:23,680 --> 00:10:26,200 found only on Borneo. 99 00:10:33,760 --> 00:10:36,000 They evolved from ancestors 100 00:10:36,000 --> 00:10:38,640 that were isolated here long ago. 101 00:10:42,080 --> 00:10:43,840 Borneo was once joined to Thailand 102 00:10:43,840 --> 00:10:46,520 and mainland Malaysia, 103 00:10:46,520 --> 00:10:48,680 part of a vast landmass, 104 00:10:48,680 --> 00:10:50,280 home to one of the oldest 105 00:10:50,280 --> 00:10:51,840 forests on Earth... 106 00:10:55,200 --> 00:10:57,520 ..but when the last Ice Age ended 107 00:10:57,520 --> 00:10:58,960 10,000 years ago, 108 00:10:58,960 --> 00:11:01,200 sea levels rose, leaving Borneo 109 00:11:01,200 --> 00:11:03,800 and its ancient forests stranded. 110 00:11:11,120 --> 00:11:13,600 The surrounding shallows now host 111 00:11:13,600 --> 00:11:16,920 some of the richest coral reefs in the world. 112 00:11:32,640 --> 00:11:34,040 A single reef 113 00:11:34,040 --> 00:11:36,920 can support more species of coral 114 00:11:36,920 --> 00:11:39,360 than the entire Caribbean Sea. 115 00:12:02,000 --> 00:12:04,360 All this abundance attracted 116 00:12:04,360 --> 00:12:07,960 a remarkable group of seafaring nomads. 117 00:12:13,600 --> 00:12:16,320 The Bajau Laut. 118 00:12:16,320 --> 00:12:18,160 People of the Sea. 119 00:12:20,400 --> 00:12:22,440 Over generations of diving, 120 00:12:22,440 --> 00:12:24,640 their bodies have transformed. 121 00:12:32,200 --> 00:12:35,440 Their spleens are 50% larger than average. 122 00:12:37,320 --> 00:12:39,520 It's believed this provides their 123 00:12:39,520 --> 00:12:42,680 blood with more oxygen for diving. 124 00:12:44,360 --> 00:12:46,120 They can hold their breath 125 00:12:46,120 --> 00:12:48,200 for over three minutes, 126 00:12:48,200 --> 00:12:51,840 and spend 60% of their day hunting underwater. 127 00:12:54,120 --> 00:12:57,760 Longer than almost any other human being. 128 00:13:20,760 --> 00:13:25,560 The Bajau Laut settled on Borneo's coasts around a thousand years ago. 129 00:13:29,400 --> 00:13:34,320 Villages like Tatagan may only be 20 miles from the nearest town... 130 00:13:36,520 --> 00:13:38,360 ..but the 200 or so people 131 00:13:38,360 --> 00:13:40,960 who live here still rely on the sea 132 00:13:40,960 --> 00:13:42,960 for nearly all their needs. 133 00:13:57,520 --> 00:14:01,120 Rajamil and his son, Fidel, 134 00:14:01,120 --> 00:14:03,520 are traditional fishermen... 135 00:14:04,840 --> 00:14:07,720 ..but they're having to adapt to the modern world. 136 00:14:33,680 --> 00:14:36,920 Plastic is the scourge of today's oceans, 137 00:14:36,920 --> 00:14:40,960 but for Rajamil and Fidel, it provides an opportunity. 138 00:14:47,320 --> 00:14:49,800 Rajamil is teaching his son 139 00:14:49,800 --> 00:14:52,120 how to turn this plastic 140 00:14:52,120 --> 00:14:53,680 into something useful. 141 00:16:29,640 --> 00:16:32,120 The lure will have to be convincing 142 00:16:32,120 --> 00:16:34,000 if it's to trick the reef's 143 00:16:34,000 --> 00:16:36,120 most intelligent resident. 144 00:16:39,720 --> 00:16:41,880 The reef octopus. 145 00:17:13,200 --> 00:17:15,320 With his new fishing technique, 146 00:17:15,320 --> 00:17:17,480 Rajamil can catch enough octopus 147 00:17:17,480 --> 00:17:20,040 to support his whole family. 148 00:17:45,000 --> 00:17:48,480 Adapting to change, the Bajau continue to live off 149 00:17:48,480 --> 00:17:51,680 one of the richest coral reefs in our seas. 150 00:17:55,480 --> 00:17:58,440 But Borneo's exceptional diversity 151 00:17:58,440 --> 00:18:01,200 only increases as you head inland... 152 00:18:04,520 --> 00:18:07,520 ..and enter one of the last surviving fragments 153 00:18:07,520 --> 00:18:10,040 of a tropical rainforest 154 00:18:10,040 --> 00:18:13,640 dating back 48 million years. 155 00:18:17,520 --> 00:18:22,280 Covering an area larger than Germany, a single square kilometre 156 00:18:22,280 --> 00:18:25,840 can hold more species of tree than the whole of Europe. 157 00:18:35,920 --> 00:18:38,640 But one group of giants dominate. 158 00:18:41,040 --> 00:18:43,040 The Dipterocarpus. 159 00:18:44,320 --> 00:18:47,200 Towering up to 100 metres high, 160 00:18:47,200 --> 00:18:51,400 they are the tallest rainforest trees in the world. 161 00:18:54,520 --> 00:18:56,920 A single fruiting tree 162 00:18:56,920 --> 00:19:00,320 can support over a thousand different species of animals. 163 00:19:07,160 --> 00:19:09,640 This leads to intense competition 164 00:19:09,640 --> 00:19:11,920 for food and space. 165 00:19:21,320 --> 00:19:23,720 To survive in these crowded canopies... 166 00:19:25,520 --> 00:19:29,160 ..life has evolved in wondrous ways. 167 00:19:51,840 --> 00:19:56,080 Borneo has over 20 species of gliding reptile. 168 00:20:05,160 --> 00:20:08,200 More than any other island on Earth. 169 00:20:34,320 --> 00:20:38,880 With nightfall, the competition in the jungle intensifies... 170 00:20:42,000 --> 00:20:44,880 ..as many of Borneo's 180 species 171 00:20:44,880 --> 00:20:47,600 of frog now burst into song. 172 00:20:47,600 --> 00:20:51,000 FROG CALL 173 00:20:55,920 --> 00:20:57,880 All singing for a mate. 174 00:21:01,160 --> 00:21:04,320 CALLING CONTINUES 175 00:21:07,880 --> 00:21:09,960 The bigger the frog, 176 00:21:09,960 --> 00:21:12,320 the louder the call. 177 00:21:17,480 --> 00:21:19,920 But this male tree-hole frog 178 00:21:19,920 --> 00:21:21,720 is barely bigger than a fingernail. 179 00:21:24,360 --> 00:21:26,640 He'll need to do something special 180 00:21:26,640 --> 00:21:28,600 if he wants to be heard by 181 00:21:28,600 --> 00:21:30,240 a nearby female. 182 00:21:32,480 --> 00:21:34,400 She may only be metres away... 183 00:21:35,960 --> 00:21:38,960 ..but the chorus from the other frogs is deafening. 184 00:21:44,320 --> 00:21:47,480 This tiny male, however, has a trick. 185 00:21:54,600 --> 00:21:56,440 He searches for a tree hole. 186 00:22:13,520 --> 00:22:15,960 The size and shape of the hole 187 00:22:15,960 --> 00:22:17,400 are critical. 188 00:22:24,560 --> 00:22:27,640 He then does something remarkable. 189 00:22:30,800 --> 00:22:33,880 FROG CALLS It begins with a soundcheck. 190 00:22:33,880 --> 00:22:36,960 CALLING CONTINUES 191 00:22:40,000 --> 00:22:41,760 Too low. 192 00:22:41,760 --> 00:22:43,360 He changes pitch. 193 00:22:43,360 --> 00:22:47,680 HIGH-PITCHED CALLING 194 00:22:47,680 --> 00:22:50,000 Too high. 195 00:22:50,000 --> 00:22:54,120 SLIGHTLY DEEPER CALLING 196 00:22:54,120 --> 00:22:55,360 That's it. 197 00:22:55,360 --> 00:22:58,400 CALLING CONTINUES 198 00:23:05,720 --> 00:23:08,800 CALLING CONTINUES 199 00:23:12,200 --> 00:23:15,640 At this specific frequency, 200 00:23:15,640 --> 00:23:18,840 the tree-hole resonates, 201 00:23:18,840 --> 00:23:22,920 amplifying the sound and broadcasting the call 202 00:23:22,920 --> 00:23:25,840 more than 50 metres across the forest. 203 00:23:31,960 --> 00:23:34,760 CALLING CONTINUES For a female, 204 00:23:34,760 --> 00:23:37,040 it's music to her ears. 205 00:23:37,040 --> 00:23:40,280 CALLING CONTINUES 206 00:23:53,760 --> 00:23:56,240 With superb directional hearing... 207 00:23:57,720 --> 00:24:00,800 ..she can home in on his calls. 208 00:24:00,800 --> 00:24:04,400 CALLING CONTINUES 209 00:24:14,360 --> 00:24:17,760 Finally, the tiny couple meet. 210 00:24:22,520 --> 00:24:24,120 Hidden from predators, 211 00:24:24,120 --> 00:24:25,960 the tree-hole will go on to make 212 00:24:25,960 --> 00:24:28,600 an ideal nursery for their tadpoles. 213 00:24:43,360 --> 00:24:46,680 Compared to the abundance of life in the treetops... 214 00:24:51,360 --> 00:24:54,800 ..on the forest floor, it's an impoverished world. 215 00:24:56,600 --> 00:24:59,080 Here, the roots of the giant trees 216 00:24:59,080 --> 00:25:00,680 suck up most of the nutrients... 217 00:25:02,560 --> 00:25:05,040 ..leaving the soil poor. 218 00:25:08,080 --> 00:25:10,240 With little to eat down here, 219 00:25:10,240 --> 00:25:12,680 many of Borneo's terrestrial mammals 220 00:25:12,680 --> 00:25:15,280 are smaller than on mainland Asia. 221 00:25:31,000 --> 00:25:34,200 Confined to her protected forest sanctuary... 222 00:25:38,760 --> 00:25:40,520 ..the exceedingly rare 223 00:25:40,520 --> 00:25:42,360 Bornean Sun Bear. 224 00:25:45,800 --> 00:25:47,560 Just over a metre long, 225 00:25:47,560 --> 00:25:50,400 it's the smallest bear in the world. 226 00:26:00,640 --> 00:26:02,680 This fallen branch 227 00:26:02,680 --> 00:26:05,480 is a valuable treat. 228 00:26:07,920 --> 00:26:10,960 Filled with wood grubs and beetles, 229 00:26:10,960 --> 00:26:13,040 nothing is wasted. 230 00:26:16,880 --> 00:26:19,440 Even a foul-tasting millipede. 231 00:26:27,440 --> 00:26:31,720 But it's not enough to sustain even this little bear. 232 00:26:33,520 --> 00:26:36,560 The real prize sits high above. 233 00:26:39,800 --> 00:26:43,040 Guided by her exceptional sense of smell... 234 00:26:43,040 --> 00:26:46,960 BUZZING 235 00:26:46,960 --> 00:26:49,160 ..it's the sweet scent of honey. 236 00:27:00,360 --> 00:27:03,400 For larger bears, this beehive 237 00:27:03,400 --> 00:27:05,000 may be out of reach... 238 00:27:12,120 --> 00:27:16,000 ..but being small helps defy gravity. 239 00:27:29,800 --> 00:27:34,680 With sharp claws and rough pads on her feet, 240 00:27:34,680 --> 00:27:38,360 she can ascend 40 metres, 241 00:27:38,360 --> 00:27:41,160 higher than any other bear. 242 00:27:45,840 --> 00:27:48,520 BUZZING 243 00:28:20,600 --> 00:28:23,600 To make it in Borneo's jungle treetops... 244 00:28:26,800 --> 00:28:28,720 ..this miniature acrobat 245 00:28:28,720 --> 00:28:31,840 has become more monkey than bear. 246 00:28:48,720 --> 00:28:51,240 For those confined to the depleted 247 00:28:51,240 --> 00:28:56,120 forest floor, survival requires innovative solutions. 248 00:29:03,680 --> 00:29:06,440 Here, mysterious signs 249 00:29:06,440 --> 00:29:08,720 line pathways through the jungle. 250 00:29:15,960 --> 00:29:18,280 Left by indigenous hunters... 251 00:29:20,720 --> 00:29:23,640 ..that have inhabited this island's jungles 252 00:29:23,640 --> 00:29:26,200 for over 4,000 years. 253 00:29:34,960 --> 00:29:39,400 Etat and Geran are Penan, native Borneans, 254 00:29:39,400 --> 00:29:42,040 and still reliant on their intimate knowledge 255 00:29:42,040 --> 00:29:44,280 of the forest to find food. 256 00:30:27,160 --> 00:30:29,440 A common fairy-bluebird. 257 00:30:29,440 --> 00:30:31,400 It's a meagre kill. 258 00:30:31,400 --> 00:30:34,840 Not enough to feed themselves, let alone their families. 259 00:30:39,680 --> 00:30:43,920 But the Penan have an ingenious way of reaching out to others. 260 00:30:48,080 --> 00:30:51,880 Along the path, they plant sticks on which they leave messages. 261 00:30:55,000 --> 00:30:58,960 A single feather signifies they have caught a small bird 262 00:30:58,960 --> 00:31:04,720 and a folded empty leaf shows that they are hungry and in need of food. 263 00:31:05,720 --> 00:31:08,960 It's an ancient sign language known as Oroo. 264 00:31:29,120 --> 00:31:31,440 With more than 50 different symbols... 265 00:31:32,960 --> 00:31:37,200 ..the Penan can communicate across 100 square miles of forest. 266 00:31:58,640 --> 00:32:03,800 Etat and Geran have found a welcome note left by fellow hunters. 267 00:32:46,760 --> 00:32:51,000 With their unique sign language and strong communal bonds, 268 00:32:51,000 --> 00:32:54,560 the Penan have overcome the challenge of finding enough food 269 00:32:54,560 --> 00:32:56,880 on Borneo's forest floor. 270 00:33:02,720 --> 00:33:06,600 In the heart of the island, looming above the rainforest, 271 00:33:06,600 --> 00:33:09,880 lies another of Borneo's diverse habitats. 272 00:33:11,640 --> 00:33:13,080 Mountains. 273 00:33:14,160 --> 00:33:18,600 Conditions may be tougher here, but they are still rich in life. 274 00:33:24,160 --> 00:33:28,320 Their range runs over 500 miles through the centre of the island. 275 00:33:33,400 --> 00:33:35,960 At over 4,000 metres, 276 00:33:35,960 --> 00:33:40,560 Mount Kinabalu is one of the highest peaks in South East Asia. 277 00:33:46,000 --> 00:33:49,040 Moist air from below cools and condenses 278 00:33:49,040 --> 00:33:51,560 into a thick veil of cloud. 279 00:33:58,120 --> 00:34:00,840 It rains here almost every day... 280 00:34:10,920 --> 00:34:14,840 ..the water washing away any goodness in the soil. 281 00:34:18,920 --> 00:34:22,920 Sheltering in ravines lie dwarf forests, 282 00:34:22,920 --> 00:34:26,600 the trees stunted from the lack of nutrients. 283 00:34:29,640 --> 00:34:34,120 These extreme conditions have pushed one group of plants 284 00:34:34,120 --> 00:34:36,880 to extraordinary lengths to survive. 285 00:34:51,560 --> 00:34:53,280 Pitcher plants. 286 00:34:59,120 --> 00:35:01,640 They have become carnivores. 287 00:35:09,880 --> 00:35:12,080 With the promise of nectar... 288 00:35:13,120 --> 00:35:15,840 ..the plant lures in its victims... 289 00:35:19,640 --> 00:35:22,120 ..onto its slippery edge. 290 00:35:27,360 --> 00:35:31,640 Below lies a pool of deadly digestive enzymes... 291 00:35:33,440 --> 00:35:35,880 ..from which there is no escape. 292 00:35:57,200 --> 00:36:00,160 The captives' bodies slowly dissolve 293 00:36:00,160 --> 00:36:02,880 in the pitcher's stomach-like vessel... 294 00:36:04,360 --> 00:36:08,200 ..providing the plant with the nutrients so lacking in the soil. 295 00:36:15,080 --> 00:36:18,960 Borneo holds over 40 species of pitcher plant, 296 00:36:18,960 --> 00:36:21,600 the greatest collection in the world... 297 00:36:23,400 --> 00:36:26,040 ..including the Hemsleyana pitcher. 298 00:36:27,680 --> 00:36:30,520 It's after something much bigger than insects. 299 00:36:37,080 --> 00:36:38,880 SCREECHING 300 00:36:39,840 --> 00:36:41,680 A woolly bat. 301 00:36:48,360 --> 00:36:51,160 Rather than using nectar as bait... 302 00:36:52,880 --> 00:36:55,560 ..the pitcher's flat lid is perfectly shaped 303 00:36:55,560 --> 00:36:57,520 to reflect the bat's sonar... 304 00:37:01,360 --> 00:37:03,200 ..drawing it in. 305 00:37:32,680 --> 00:37:35,120 But the woolly bat is safe. 306 00:37:37,600 --> 00:37:41,840 After a night's hunting, this bat needs a place to shelter. 307 00:37:44,480 --> 00:37:47,720 Rather than fall into its lethal pool, 308 00:37:47,720 --> 00:37:51,560 the bat fits snuggly into the pitcher's tapered cup. 309 00:38:01,920 --> 00:38:04,000 In the heat of the day, 310 00:38:04,000 --> 00:38:07,800 the pitcher's waxy walls even keep its guest cool. 311 00:38:21,440 --> 00:38:25,280 How the plant benefits only becomes apparent at dusk. 312 00:38:35,520 --> 00:38:37,880 The nocturnal guest awakens... 313 00:38:57,400 --> 00:38:59,800 ..leaving behind its payment. 314 00:39:04,920 --> 00:39:09,840 Nutrient-rich bat droppings, known as guano. 315 00:39:14,240 --> 00:39:17,160 This plant has tapped into one of the greatest sources 316 00:39:17,160 --> 00:39:19,080 of nutrients on the island. 317 00:39:23,400 --> 00:39:27,360 One that has created a world of remarkable diversity 318 00:39:27,360 --> 00:39:30,080 in the most surprising place of all. 319 00:39:31,440 --> 00:39:35,560 The deluge of rain has carved out one of the largest cave chambers 320 00:39:35,560 --> 00:39:37,200 in the world. 321 00:39:40,840 --> 00:39:43,440 Known as Deer Cave, 322 00:39:43,440 --> 00:39:47,560 at places it's almost 200 metres wide. 323 00:39:48,760 --> 00:39:51,800 Big enough to fly a jumbo jet through. 324 00:39:54,240 --> 00:39:56,240 SCREECHING 325 00:40:15,000 --> 00:40:18,160 As the sun sets, a great exodus begins. 326 00:40:20,680 --> 00:40:23,440 Emerging from caves across the island, 327 00:40:23,440 --> 00:40:26,320 millions of bats spread out over the forest. 328 00:40:42,200 --> 00:40:46,280 They are the most numerous mammal on Borneo, 329 00:40:46,280 --> 00:40:48,920 and their impact is immense. 330 00:40:49,920 --> 00:40:52,960 The bats from Deer Cave alone are thought to catch 331 00:40:52,960 --> 00:40:56,600 up to 36 tonnes of forest insects every night. 332 00:41:11,960 --> 00:41:15,960 At dawn, they return to the cave to roost, 333 00:41:15,960 --> 00:41:19,200 where their excrement falls like rain... 334 00:41:22,240 --> 00:41:25,880 ..building, over centuries, mountains of guano 335 00:41:25,880 --> 00:41:28,720 more than 15 metres high. 336 00:41:34,440 --> 00:41:38,640 Feeding on it is one of the largest concentrations of cockroaches 337 00:41:38,640 --> 00:41:40,440 in the world... 338 00:41:54,680 --> 00:41:56,960 ..as well as a wealth of other creatures. 339 00:42:00,120 --> 00:42:02,040 Foot-long centipedes. 340 00:42:04,880 --> 00:42:06,880 Giant cave spiders. 341 00:42:12,160 --> 00:42:14,160 Even a cave crab. 342 00:42:29,480 --> 00:42:34,560 Thanks to the bats, even in this extreme habitat, 343 00:42:34,560 --> 00:42:38,960 Borneo harbours an extraordinary array of life. 344 00:42:45,880 --> 00:42:47,960 For 10,000 years, 345 00:42:47,960 --> 00:42:51,360 this remote island's astonishing biodiversity 346 00:42:51,360 --> 00:42:53,880 has been protected by its isolation. 347 00:42:56,880 --> 00:42:58,920 MONKEY HOWLS 348 00:42:59,920 --> 00:43:01,960 CHAINSAW ROARS 349 00:43:01,960 --> 00:43:05,240 But with the arrival of industrial logging and farming 350 00:43:05,240 --> 00:43:08,880 in the last 50 years, all this has changed. 351 00:43:18,040 --> 00:43:22,880 Today, over half of its ancient rainforests have been cleared. 352 00:43:29,000 --> 00:43:32,440 Felled for timber, much of the land has been turned 353 00:43:32,440 --> 00:43:36,080 into vast plantations for crops such as palm oil. 354 00:43:47,840 --> 00:43:50,320 With the destruction of the forests, 355 00:43:50,320 --> 00:43:53,920 researchers like Twentinolosa are increasingly concerned 356 00:43:53,920 --> 00:43:57,200 about the future of Borneo's most iconic resident. 357 00:43:59,840 --> 00:44:01,840 The orangutan. 358 00:44:39,880 --> 00:44:42,720 His work has helped us understand 359 00:44:42,720 --> 00:44:46,560 just how clever these great apes really are. 360 00:44:49,760 --> 00:44:53,000 Many of the forest leaves are poisonous, 361 00:44:53,000 --> 00:44:57,920 but a mother can identify around 500 species that are safe to eat. 362 00:45:01,440 --> 00:45:05,840 Vital knowledge that she will pass on to future generations. 363 00:45:15,200 --> 00:45:18,880 One particular orangutan has led researchers 364 00:45:18,880 --> 00:45:20,880 to a breakthrough discovery. 365 00:46:13,920 --> 00:46:17,960 Years of carrying a heavy baby have taken their toll. 366 00:46:19,600 --> 00:46:23,320 It appears Indah is suffering from aching joints. 367 00:46:25,400 --> 00:46:28,960 The medicinal paste she creates contains powerful 368 00:46:28,960 --> 00:46:32,400 anti-inflammatories, thought to ease her pain. 369 00:46:36,680 --> 00:46:40,120 Indah's vast knowledge of these ancient forests 370 00:46:40,120 --> 00:46:42,920 includes a treatment for arthritis. 371 00:46:54,960 --> 00:46:58,920 But as their rainforest homes are destroyed, 372 00:46:58,920 --> 00:47:03,400 their future, along with Borneo's other unique plants and animals, 373 00:47:03,400 --> 00:47:05,080 are under threat. 374 00:47:33,400 --> 00:47:39,120 In under 20 years, half of all Borneo's orangutans 375 00:47:39,120 --> 00:47:41,440 have been lost. 376 00:47:41,440 --> 00:47:46,120 An average of 100 killed every week. 377 00:47:52,120 --> 00:47:54,840 Over thousands of years, 378 00:47:54,840 --> 00:47:57,880 Borneo's wide variety of habitats... 379 00:47:59,320 --> 00:48:01,840 ..from its bustling coral reefs... 380 00:48:04,920 --> 00:48:06,920 ..ancient forests... 381 00:48:08,320 --> 00:48:10,880 ..and remote mountain peaks... 382 00:48:15,600 --> 00:48:19,840 ..have been the birthplace of thousands of unique species. 383 00:48:29,200 --> 00:48:32,880 But with the continued destruction of their home, 384 00:48:32,880 --> 00:48:38,320 how much longer can these remarkable animals survive? 385 00:48:56,240 --> 00:48:59,840 Filming Borneo's staggering wild diversity presented the team 386 00:48:59,840 --> 00:49:01,560 with many challenges. 387 00:49:01,560 --> 00:49:03,960 These jungles are designed for pain. 388 00:49:03,960 --> 00:49:08,880 There's scorpions, spiders, snakes, bees, leeches. It's horrible. 389 00:49:08,880 --> 00:49:10,840 Ow, ow. Fire ants. 390 00:49:10,840 --> 00:49:13,080 Ooh, ow... Ow, ow, ow. 391 00:49:13,080 --> 00:49:14,680 Are you OK? 392 00:49:15,960 --> 00:49:18,960 But their greatest challenge was capturing the moment 393 00:49:18,960 --> 00:49:22,200 proboscis monkeys make their dramatic leaps across rivers 394 00:49:22,200 --> 00:49:24,160 patrolled by crocodiles. 395 00:49:35,240 --> 00:49:38,480 One of the proboscis monkey's last strongholds 396 00:49:38,480 --> 00:49:43,360 is a 150-square-mile area of flooded forest known as the Kinabatangan. 397 00:49:46,200 --> 00:49:50,040 The only way for the crew to find and film these semi-aquatic monkeys 398 00:49:50,040 --> 00:49:51,600 is by boat. 399 00:49:53,200 --> 00:49:56,560 For the next two weeks, director Georgie Ward 400 00:49:56,560 --> 00:49:59,200 and cameraman Neil Anderson must navigate 401 00:49:59,200 --> 00:50:02,200 its intricate network of waterways, 402 00:50:02,200 --> 00:50:04,800 guided by naturalist Cede Prudente, 403 00:50:04,800 --> 00:50:07,880 who has worked on these rivers for over 20 years. 404 00:50:09,960 --> 00:50:12,400 His extensive experience quickly pays off... 405 00:50:12,400 --> 00:50:14,000 There it is. 406 00:50:14,000 --> 00:50:16,360 ..as he tunes in to the monkeys' calls. 407 00:50:17,480 --> 00:50:18,920 Yeah. 408 00:50:18,920 --> 00:50:23,160 There's no visual, but we can hear them further inland. 409 00:50:25,240 --> 00:50:28,920 Hearing the monkeys is one thing, but following them through 410 00:50:28,920 --> 00:50:31,560 the impenetrable jungle is near impossible. 411 00:50:31,560 --> 00:50:34,080 We're not finding anyone yet. 412 00:50:36,120 --> 00:50:38,440 Confined to the river's edge, 413 00:50:38,440 --> 00:50:41,920 the crew must wait patiently for the proboscis to come to them. 414 00:50:41,920 --> 00:50:44,520 Oh, there's a group here. See, this is the male. 415 00:50:44,520 --> 00:50:46,560 After several days of searching, 416 00:50:46,560 --> 00:50:49,880 Cede tracks down a troop of monkeys perched on the river bank. 417 00:50:49,880 --> 00:50:53,400 So we've just stopped and I've got my first glimpse of a proboscis, 418 00:50:53,400 --> 00:50:55,160 which is really exciting. 419 00:50:56,160 --> 00:50:59,880 For Georgie, there's one individual that really stands out. 420 00:50:59,880 --> 00:51:01,920 Oh, he's huge. 421 00:51:01,920 --> 00:51:04,000 The male's got this massive nose 422 00:51:04,000 --> 00:51:06,640 and these eyes that just kind of stare at you. 423 00:51:06,640 --> 00:51:09,920 The crew ready themselves for the monkeys to jump. 424 00:51:10,960 --> 00:51:13,560 Oh, there's a few of them on there now. 425 00:51:13,560 --> 00:51:16,000 But the troop change their minds. 426 00:51:16,000 --> 00:51:18,800 The monkeys have literally just turned 427 00:51:18,800 --> 00:51:21,440 and gone back into the forest. 428 00:51:22,840 --> 00:51:24,920 While the proboscis retreat, 429 00:51:24,920 --> 00:51:28,360 Cede gets news of another troop also close to the river's edge. 430 00:51:31,200 --> 00:51:33,120 OK, OK. Chien, let's go. 431 00:51:34,880 --> 00:51:40,280 So the other boat has seen monkeys, so hopefully we haven't missed it. 432 00:51:40,280 --> 00:51:42,280 OK, OK. 433 00:51:46,960 --> 00:51:49,720 There's a bit of movement in the trees so it looks like 434 00:51:49,720 --> 00:51:52,640 they could jump, so Neil's just getting his camera ready. 435 00:51:52,640 --> 00:51:56,400 OK, Neil? Neil? Yeah, I've got them. Wow, there's the big male. 436 00:51:56,400 --> 00:51:59,800 Keep an eye, because I think that's going to just jump in the river. 437 00:51:59,800 --> 00:52:02,440 Just focus on the tree. 438 00:52:02,440 --> 00:52:05,120 But once again, the monkeys take fright. 439 00:52:06,720 --> 00:52:09,800 And this time, it's clear to see why. 440 00:52:12,680 --> 00:52:15,880 No wonder they're nervous about crossing the river. 441 00:52:16,880 --> 00:52:20,960 We've spotted a massive crocodile. 442 00:52:21,880 --> 00:52:23,840 It is huge. 443 00:52:23,840 --> 00:52:26,600 I'm pretty happy that we're still a good 20 metres 444 00:52:26,600 --> 00:52:28,560 away from it, to be honest. 445 00:52:34,000 --> 00:52:36,600 For today at least, the troop has lost its appetite 446 00:52:36,600 --> 00:52:39,480 for the new leaves across the river, 447 00:52:39,480 --> 00:52:42,640 and eventually the monkeys bed down for the night. 448 00:52:45,440 --> 00:52:48,600 Dawn the next day, and the crew head back to the troop... 449 00:52:50,640 --> 00:52:54,680 ..only to be caught out by one of Borneo's tropical downpours. 450 00:52:54,680 --> 00:52:56,400 THUNDER 451 00:52:56,400 --> 00:53:00,160 Six inches of rain can fall here in a single day. 452 00:53:00,160 --> 00:53:02,760 More than the UK gets in a month. 453 00:53:18,880 --> 00:53:22,720 But the downpour continues, giving the crew little choice 454 00:53:22,720 --> 00:53:25,560 but to beat a hasty retreat back to base. 455 00:53:29,040 --> 00:53:32,840 With less than a week's filming left, they're running out of time. 456 00:53:33,880 --> 00:53:37,360 We just want to get out there. It's quite frustrating. 457 00:53:38,960 --> 00:53:41,200 Finally, with a break in the weather, 458 00:53:41,200 --> 00:53:43,200 the team can head out again. 459 00:53:44,280 --> 00:53:47,520 This time, Cede leads them to a new part of the flooded forest. 460 00:53:53,000 --> 00:53:55,280 They find a troop crossing the river. 461 00:53:56,640 --> 00:53:59,680 But they're taking the easy route across. 462 00:53:59,680 --> 00:54:02,440 It's good to see the monkeys out in the open eventually, 463 00:54:02,440 --> 00:54:05,200 but if they're going to keep using these bridges, 464 00:54:05,200 --> 00:54:08,120 we'd better go a bit, maybe, further downriver. 465 00:54:09,240 --> 00:54:13,120 Although these rope bridges provide safe passage for the proboscis, 466 00:54:13,120 --> 00:54:16,160 they are designed to help Borneo's biggest primate. 467 00:54:16,160 --> 00:54:19,400 Just somewhere behind the big tree to the right. 468 00:54:23,680 --> 00:54:28,360 We've got this tiny little intimate view of an orangutan 469 00:54:28,360 --> 00:54:33,120 feeding on termites, which is quite rare to see. 470 00:54:33,120 --> 00:54:36,640 Borneo's orangutan is critically endangered. 471 00:54:37,680 --> 00:54:40,720 The rope bridges give these great apes access 472 00:54:40,720 --> 00:54:43,800 to the last strips of forest that line the river banks... 473 00:54:43,800 --> 00:54:45,960 DRONE WHIRS 474 00:54:45,960 --> 00:54:49,120 ..which are all that remain of their habitat here. 475 00:54:50,200 --> 00:54:55,880 Literally 20 metres behind the trees is a huge palm oil plantation. 476 00:54:59,640 --> 00:55:02,880 When I say huge, it just goes on and on to the horizon. 477 00:55:02,880 --> 00:55:04,880 That is unbelievable. 478 00:55:07,360 --> 00:55:11,000 In the old days, when I was here 25 years ago, 479 00:55:11,000 --> 00:55:13,600 a lot of this was forest - natural forest. 480 00:55:16,480 --> 00:55:20,200 With so much of their natural vegetation destroyed, 481 00:55:20,200 --> 00:55:23,360 proboscis monkeys are also highly endangered. 482 00:55:25,880 --> 00:55:29,000 Still, Cede remains hopeful. 483 00:55:29,000 --> 00:55:32,720 It's not too late, so whatever we have now, I think we just need to 484 00:55:32,720 --> 00:55:37,000 improve the management, and I guess the oil palm plantation 485 00:55:37,000 --> 00:55:39,360 has to work with NGOs and government, 486 00:55:39,360 --> 00:55:41,440 so they play a big role. 487 00:55:43,280 --> 00:55:45,960 Returning to the heart of the flooded forest, 488 00:55:45,960 --> 00:55:48,360 they receive news of another proboscis troop 489 00:55:48,360 --> 00:55:50,360 poised to cross the river. 490 00:55:54,400 --> 00:55:56,720 With the shoot almost out of time, 491 00:55:56,720 --> 00:55:59,360 this could be the crew's last opportunity 492 00:55:59,360 --> 00:56:02,120 to capture the monkeys' elusive river crossing. 493 00:56:06,000 --> 00:56:08,680 This is the closest we've got to seeing them jump. 494 00:56:08,680 --> 00:56:11,280 I hope this is it. My heart is racing. 495 00:56:13,160 --> 00:56:15,800 OK, OK, OK. Ready, ready, ready. Ready, ready. 496 00:56:15,800 --> 00:56:19,640 One, two, three.... 497 00:56:19,640 --> 00:56:21,120 Go! 498 00:56:31,440 --> 00:56:32,880 Wow. 499 00:56:33,840 --> 00:56:36,520 OK, ready? OK. 500 00:56:37,520 --> 00:56:38,880 Wow. 501 00:56:41,960 --> 00:56:43,840 Oh, my gosh. 502 00:56:45,440 --> 00:56:47,240 Ah, the big male. 503 00:57:00,720 --> 00:57:03,600 But a mother and baby have been left behind. 504 00:57:05,160 --> 00:57:08,200 All the rest of the group have already crossed. 505 00:57:08,200 --> 00:57:11,840 The wary female may have spotted a crocodile. 506 00:57:15,120 --> 00:57:17,120 Oh, my gosh, she's jumped. 507 00:57:22,840 --> 00:57:24,680 Oh, my gosh. 508 00:57:24,680 --> 00:57:27,720 Ah, it's just her head, just her head, 509 00:57:27,720 --> 00:57:30,120 out the water, holding her nose up. 510 00:57:31,640 --> 00:57:34,160 Come on, come on. Come on, go. 511 00:57:40,160 --> 00:57:42,840 I'm so happy. I'm so happy and relieved. 512 00:57:43,920 --> 00:57:46,200 Great work, team. Amazing. 513 00:57:46,200 --> 00:57:49,640 Excellent. Yes. High fives all round, guys. 514 00:57:49,640 --> 00:57:52,320 That was brilliant. Wow, well done. That was great. 515 00:57:53,920 --> 00:57:57,080 We've been here for weeks but that is the moment, 516 00:57:57,080 --> 00:58:00,000 that leap, that jump, that crossing of the river 517 00:58:00,000 --> 00:58:03,440 for them to get to the other side, get away from those crocs, 518 00:58:03,440 --> 00:58:08,320 so, yeah, quite a special moment to actually experience that. 519 00:58:09,640 --> 00:58:12,400 This dramatic footage provides fresh insight 520 00:58:12,400 --> 00:58:15,080 into the lives of these remarkable monkeys... 521 00:58:16,040 --> 00:58:19,400 ..but as their forest home continues to be destroyed, 522 00:58:19,400 --> 00:58:24,160 even greater challenges lie ahead on this rapidly changing island. 523 00:58:28,200 --> 00:58:30,480 Next time, Hawaii. 524 00:58:30,480 --> 00:58:33,880 The most remote island chain on Earth. 525 00:58:37,320 --> 00:58:39,960 From its lush forested peaks 526 00:58:39,960 --> 00:58:43,920 to its low-lying sandy atolls, 527 00:58:43,920 --> 00:58:49,360 its varied islands are home to extraordinary wildlife, 528 00:58:49,360 --> 00:58:52,040 thriving against the odds.