1 00:00:02,569 --> 00:00:06,573 In the wild, there are alliances everywhere. 2 00:00:08,408 --> 00:00:10,744 But they're not always mutual. 3 00:00:11,678 --> 00:00:14,514 This lemur is crawling with parasites. 4 00:00:16,850 --> 00:00:18,352 This millipede isn't. 5 00:00:19,052 --> 00:00:22,189 ♪ ♪ 6 00:00:23,023 --> 00:00:26,293 What happens next is very weird. 7 00:00:35,302 --> 00:00:40,140 The creatures of Earth are wilder than you 8 00:00:40,274 --> 00:00:42,376 could possibly imagine. 9 00:00:44,511 --> 00:00:51,585 Among the fast and fearsome are the astoundingly crazy. 10 00:00:54,721 --> 00:00:59,860 With strange behavior and outrageous fashion sense. 11 00:01:02,396 --> 00:01:04,865 They're all in a competition to survive. 12 00:01:06,466 --> 00:01:09,403 And weirdness always wins. 13 00:01:27,554 --> 00:01:30,590 ♪ ♪ 14 00:01:31,725 --> 00:01:35,495 In the pantheon of sidekicks, we must reserve pride of 15 00:01:35,629 --> 00:01:37,898 place for one of the giants. 16 00:01:40,968 --> 00:01:44,638 A little guy who keeps herbivores all over the world, 17 00:01:44,771 --> 00:01:49,843 pest-free and healthy, with his titanic appetite for crap. 18 00:01:58,719 --> 00:02:03,991 Dung beetles, described by some entomologists 19 00:02:04,124 --> 00:02:06,159 as God's gift to Earth. 20 00:02:10,731 --> 00:02:14,434 Without these essential septic sidekicks acting as 21 00:02:14,568 --> 00:02:18,772 clean-up crew, we'd all be swimming in poo. 22 00:02:19,906 --> 00:02:22,876 ♪ ♪ 23 00:02:37,624 --> 00:02:40,494 There are almost 10,000 different species of 24 00:02:40,627 --> 00:02:42,929 dung beetles around the world, and they've 25 00:02:43,063 --> 00:02:47,300 been breaking down droppings since the days of the dinosaurs. 26 00:02:50,070 --> 00:02:54,074 We might avoid it, but for them, it's brown gold, 27 00:02:54,207 --> 00:02:56,710 which they hide like buried treasure. 28 00:03:00,013 --> 00:03:03,850 Eating it and fertilizing the soil all at once. 29 00:03:07,020 --> 00:03:08,388 Don't poo-poo the poo! 30 00:03:09,756 --> 00:03:12,459 It's full of partially digested food. 31 00:03:17,564 --> 00:03:20,033 This dung beetle's super-sensitive antennae 32 00:03:20,200 --> 00:03:21,868 have gone into overdrive. 33 00:03:25,439 --> 00:03:30,844 It knows somewhere out there, fresh feces. 34 00:03:33,113 --> 00:03:36,216 ♪ ♪ 35 00:03:36,917 --> 00:03:39,786 ♪ ♪ 36 00:03:40,020 --> 00:03:42,656 But other beetles have picked up the scent too. 37 00:03:43,256 --> 00:03:46,393 ♪ ♪ 38 00:03:46,793 --> 00:03:49,763 ♪ ♪ 39 00:03:52,399 --> 00:03:53,767 He's gotta move fast. 40 00:03:56,103 --> 00:03:56,870 Wing it! 41 00:03:57,671 --> 00:04:00,707 ♪ ♪ 42 00:04:00,941 --> 00:04:03,844 ♪ ♪ 43 00:04:05,212 --> 00:04:07,981 He follows the scent for over two miles. 44 00:04:09,483 --> 00:04:13,186 There it is, a sweet pile of scat. 45 00:04:17,557 --> 00:04:19,993 This load is juicy good. 46 00:04:20,894 --> 00:04:25,298 Great water content and heaps of plant material intact. 47 00:04:26,233 --> 00:04:28,335 It's exactly what he needs. 48 00:04:31,371 --> 00:04:34,641 The cow wants it gone and the removal guy is here. 49 00:04:40,780 --> 00:04:41,715 Time to roll. 50 00:04:42,883 --> 00:04:45,919 ♪ ♪ 51 00:04:46,286 --> 00:04:49,256 ♪ ♪ 52 00:04:49,890 --> 00:04:53,460 However, his poop prize has drawn attention. 53 00:04:57,564 --> 00:05:00,500 This rival male wants it for himself. 54 00:05:01,001 --> 00:05:03,970 ♪ ♪ 55 00:05:04,671 --> 00:05:07,641 ♪ ♪ 56 00:05:11,545 --> 00:05:14,581 With the astounding ability to move objects 57 00:05:14,714 --> 00:05:16,850 1,000 times his own weight, 58 00:05:17,717 --> 00:05:21,521 he rolls the challenger and the dung ball together. 59 00:05:21,988 --> 00:05:24,958 ♪ ♪ 60 00:05:25,559 --> 00:05:28,528 ♪ ♪ 61 00:05:32,699 --> 00:05:33,567 Body slam! 62 00:05:37,170 --> 00:05:39,406 The bandit is vanquished. 63 00:05:49,149 --> 00:05:50,884 But the job's not done yet. 64 00:05:52,786 --> 00:05:57,624 His home and partner are still 200 yards away. 65 00:05:59,993 --> 00:06:04,397 Luckily, dung beetles are incredible navigators. 66 00:06:05,966 --> 00:06:13,607 By day they use the sun and by night they even use celestial 67 00:06:13,740 --> 00:06:16,476 navigation to plot their course. 68 00:06:17,143 --> 00:06:20,280 ♪ ♪ 69 00:06:21,882 --> 00:06:24,818 ♪ ♪ 70 00:06:25,785 --> 00:06:28,755 ♪ ♪ 71 00:06:29,956 --> 00:06:31,892 Finally he reaches home. 72 00:06:33,193 --> 00:06:36,329 ♪ ♪ 73 00:06:37,964 --> 00:06:42,702 The waiting female buries the dung gift by the entrance 74 00:06:42,836 --> 00:06:44,204 to their mating tunnel. 75 00:06:45,505 --> 00:06:49,976 The dung ball becomes a source of food and a nursery 76 00:06:50,110 --> 00:06:51,544 for the female's eggs. 77 00:06:55,148 --> 00:06:59,286 The larvae that hatch grow big on essential nutrients, 78 00:07:00,954 --> 00:07:06,693 creating a whole new generation of guano aficionados. 79 00:07:21,508 --> 00:07:26,813 This young meat-eating vine has a very grown-up problem. 80 00:07:27,580 --> 00:07:30,517 ♪ ♪ 81 00:07:32,619 --> 00:07:37,390 The cloud forests of Borneo are a hard place to find food, 82 00:07:38,992 --> 00:07:42,295 especially when you're rooted to the spot. 83 00:07:45,498 --> 00:07:50,503 But if this juvenile pitcher plant grows old enough and high enough, 84 00:07:51,571 --> 00:07:55,041 it may one day team up to form one of the 85 00:07:55,175 --> 00:07:57,711 forest's most dynamic duos. 86 00:08:09,489 --> 00:08:13,960 The young pitcher plant begins life at ground level as an 87 00:08:14,094 --> 00:08:16,496 everyday carnivorous vine. 88 00:08:19,699 --> 00:08:23,603 Stealing essential nitrogen from unsuspecting bugs. 89 00:08:25,705 --> 00:08:29,442 Its modified leaves are a trap, luring insects 90 00:08:29,576 --> 00:08:31,411 with its special nectar. 91 00:08:35,248 --> 00:08:41,654 One false move or even a badly timed raindrop and they fall 92 00:08:41,788 --> 00:08:47,494 into the chamber of horrors where the plant digests them. 93 00:08:48,595 --> 00:08:51,564 ♪ ♪ 94 00:09:00,006 --> 00:09:03,610 As the plant matures, so does its palate. 95 00:09:05,945 --> 00:09:08,882 ♪ ♪ 96 00:09:13,052 --> 00:09:17,257 When the plant was younger, this Tree Shrew would 97 00:09:17,390 --> 00:09:18,658 have spelled danger. 98 00:09:20,660 --> 00:09:28,468 But now the older pitcher has a deep appreciation for dung. 99 00:09:29,602 --> 00:09:33,273 It's developed a new type of trap that looks 100 00:09:33,406 --> 00:09:35,575 and works like a toilet. 101 00:09:39,345 --> 00:09:43,283 The shrew's just here to lap up the pitcher's sweet nectar. 102 00:09:51,357 --> 00:09:54,360 The sugary fluid gives him all the energy he'll 103 00:09:54,494 --> 00:09:56,763 need for hard foraging. 104 00:09:59,132 --> 00:10:02,435 He doesn't even take a toilet break, lest someone 105 00:10:02,569 --> 00:10:03,937 else get to the food. 106 00:10:06,840 --> 00:10:10,043 But when you gotta go, you gotta go. 107 00:10:11,845 --> 00:10:12,879 Huh? 108 00:10:14,080 --> 00:10:19,152 In one of the weirdest examples of co-evolution, this is how the 109 00:10:19,285 --> 00:10:23,823 mature pitcher plant now makes its way in the cloud forest. 110 00:10:26,459 --> 00:10:30,163 Because shrew's scat is rich in nutrients. 111 00:10:33,566 --> 00:10:36,703 Precious treasure in this habitat. 112 00:10:52,152 --> 00:10:55,288 ♪ ♪ 113 00:10:57,857 --> 00:11:00,960 The Sea Anemone is a noxious killer. 114 00:11:04,464 --> 00:11:06,499 Deploying stinging nematocysts on their 115 00:11:06,633 --> 00:11:10,370 tentacles to subdue prey. 116 00:11:11,504 --> 00:11:13,973 Pumping them with lethal toxins. 117 00:11:17,977 --> 00:11:24,951 From fish to Sea Hares. 118 00:11:29,289 --> 00:11:31,558 If they can trap it, they'll eat it. 119 00:11:35,428 --> 00:11:38,431 Even their jellyfish cousins can't get a pass. 120 00:11:39,766 --> 00:11:42,502 Look away now if you're squeamish, 121 00:11:42,635 --> 00:11:45,572 because victims have no chance. 122 00:11:51,544 --> 00:11:55,048 When it comes to their turf, sea anemones will 123 00:11:55,181 --> 00:11:57,317 take down anyone who crosses them. 124 00:11:59,519 --> 00:12:02,255 But for these iconic little fish, 125 00:12:02,388 --> 00:12:04,290 the anemone's a sweetheart. 126 00:12:07,427 --> 00:12:08,928 A wingman for life. 127 00:12:18,771 --> 00:12:21,741 ♪ ♪ 128 00:12:23,943 --> 00:12:29,616 Living among a deadly sway of tentacles, a layer of thick 129 00:12:29,749 --> 00:12:33,720 slime protects clownfish from the anemone's sting. 130 00:12:36,055 --> 00:12:39,459 So when it comes time to start a clownfish family of its own, 131 00:12:39,592 --> 00:12:42,962 there's no better place to lay eggs. 132 00:12:54,974 --> 00:12:58,778 Surrounded by tentacles, they're safe from any 133 00:12:58,911 --> 00:13:00,647 marauding egg thieves. 134 00:13:04,717 --> 00:13:08,288 This doting father takes great care of the eggs. 135 00:13:15,495 --> 00:13:18,798 And maintains the household in his spare time. 136 00:13:20,967 --> 00:13:23,436 In return for the anemone's protection, 137 00:13:23,569 --> 00:13:25,538 he removes its parasites. 138 00:13:27,907 --> 00:13:30,877 ♪ ♪ 139 00:13:33,946 --> 00:13:38,184 And chases away other fish who want to feed on their home. 140 00:13:39,886 --> 00:13:42,922 ♪ ♪ 141 00:13:43,690 --> 00:13:47,260 But the biggest bonus comes from his feces. 142 00:13:50,730 --> 00:13:54,801 Ammonia-rich waste is fantastic fertilizer. 143 00:13:54,934 --> 00:13:58,705 It helps the anemone breathe, grow, and reproduce. 144 00:13:59,839 --> 00:14:02,809 ♪ ♪ 145 00:14:08,247 --> 00:14:11,918 Under constant protection of the parents and the anemone, 146 00:14:12,051 --> 00:14:13,753 the eggs develop. 147 00:14:15,088 --> 00:14:18,224 ♪ ♪ 148 00:14:20,860 --> 00:14:23,830 ♪ ♪ 149 00:14:30,036 --> 00:14:34,741 A week later, they hatch under the cover of darkness. 150 00:14:36,876 --> 00:14:39,846 ♪ ♪ 151 00:14:42,815 --> 00:14:46,219 Once born, baby clownfish take a little time to 152 00:14:46,352 --> 00:14:47,854 acclimatize to the anemone. 153 00:14:54,394 --> 00:14:57,663 Rubbing themselves on its tentacles over and over, 154 00:14:57,797 --> 00:15:04,704 the young fish acquire a kind of chemical camouflage. 155 00:15:06,572 --> 00:15:08,775 The anemone is no longer 156 00:15:08,908 --> 00:15:12,612 able to distinguish between itself and the clownfish. 157 00:15:14,814 --> 00:15:18,251 Bonded together, the two will become one of the 158 00:15:18,384 --> 00:15:20,553 ocean's ultimate allies. 159 00:15:30,296 --> 00:15:33,599 Trusty sidekicks come in all shapes and sizes. 160 00:15:39,906 --> 00:15:45,945 But what happens when that trust is repaired by cold betrayal? 161 00:15:47,446 --> 00:15:48,681 No, not the hippo. 162 00:15:50,516 --> 00:15:55,254 Say hello to his little friend, the oxpecker. 163 00:16:08,901 --> 00:16:12,271 Africa's dry season is a particularly difficult 164 00:16:12,405 --> 00:16:13,973 time for the animals here. 165 00:16:16,209 --> 00:16:22,081 The only thing worse than the heat are the hordes of bugs 166 00:16:22,215 --> 00:16:23,850 that plague its residents. 167 00:16:27,787 --> 00:16:31,724 To make life tolerable, you've got to take any help on offer. 168 00:16:35,895 --> 00:16:40,633 Red-billed oxpeckers run an on-the-go housekeeping service. 169 00:16:42,935 --> 00:16:44,704 And business is brisk. 170 00:16:45,671 --> 00:16:48,641 ♪ ♪ 171 00:16:57,917 --> 00:17:02,955 The red bill is surprisingly dexterous and gets right 172 00:17:03,089 --> 00:17:04,557 in where it needs to. 173 00:17:08,828 --> 00:17:11,297 The birds and beasts form a classic 174 00:17:11,430 --> 00:17:13,366 mutualistic relationship. 175 00:17:14,267 --> 00:17:17,403 ♪ ♪ 176 00:17:19,538 --> 00:17:22,875 Like tiny scissors, the oxpecker's bill scythes 177 00:17:23,009 --> 00:17:24,877 through the top layer of fur. 178 00:17:38,491 --> 00:17:41,961 But in the dry season, overcrowded bathing spots 179 00:17:42,094 --> 00:17:43,963 cause tempers to rise. 180 00:17:47,433 --> 00:17:49,468 Hippos war for territory. 181 00:17:54,006 --> 00:17:56,976 ♪ ♪ 182 00:18:04,050 --> 00:18:07,186 ♪ ♪ 183 00:18:14,060 --> 00:18:17,196 ♪ ♪ 184 00:18:23,636 --> 00:18:26,305 The winner gets the last patch of water. 185 00:18:29,008 --> 00:18:32,979 The loser gets covered in bloody wounds. 186 00:18:36,849 --> 00:18:38,684 He could do with a bit of attention. 187 00:18:41,854 --> 00:18:46,258 Oxpeckers clean the scratches and prevent infections. 188 00:18:47,026 --> 00:18:50,062 ♪ ♪ 189 00:18:50,997 --> 00:18:54,934 They've switched gear to become parasites themselves, 190 00:18:58,304 --> 00:19:01,674 feeding on the hippo's flowing blood. 191 00:19:06,178 --> 00:19:11,450 Oxpeckers have learned that incessant pecking can stop scabs 192 00:19:11,584 --> 00:19:15,154 from forming, leaving wounds open. 193 00:19:18,324 --> 00:19:23,329 Warm blood on tap whenever they need a drink. 194 00:19:25,064 --> 00:19:28,200 ♪ ♪ 195 00:19:30,703 --> 00:19:33,939 Over weeks, the wounds get bigger and the 196 00:19:34,073 --> 00:19:35,474 oxpeckers keep at it. 197 00:19:46,018 --> 00:19:49,889 Eventually the hippo dies from secondary infections. 198 00:19:53,125 --> 00:19:56,262 ♪ ♪ 199 00:19:57,096 --> 00:19:59,832 A tragedy for the hippos, 200 00:20:00,700 --> 00:20:03,869 but a treasure for the voracious oxpeckers. 201 00:20:05,504 --> 00:20:08,708 Sidekicks that will kick you when you're down. 202 00:20:27,026 --> 00:20:28,427 Take-offs are tricky. 203 00:20:34,266 --> 00:20:35,835 Landings are iffy. 204 00:20:41,774 --> 00:20:44,610 And the hairless head is a travesty. 205 00:20:47,546 --> 00:20:51,050 But if you want to make an inconvenient body disappear, 206 00:20:51,183 --> 00:20:52,918 look no further. 207 00:21:07,867 --> 00:21:13,739 With stomach acids that dissolve metal, vultures are the 208 00:21:13,873 --> 00:21:18,844 sidekicks humans don't deserve, but absolutely need. 209 00:21:35,294 --> 00:21:41,467 Make them an offer of rotting flesh and they never refuse. 210 00:21:54,413 --> 00:21:57,683 They can finish off a small animal carcass 211 00:21:57,816 --> 00:21:59,185 in half an hour flat. 212 00:22:07,426 --> 00:22:10,896 Decaying carcasses often breed deadly anthrax, 213 00:22:12,565 --> 00:22:15,568 botulinum toxins and rabies. 214 00:22:17,903 --> 00:22:20,706 Vultures keep these diseases in check. 215 00:22:27,846 --> 00:22:32,284 Masters of high altitude flight, vultures typically climb to 216 00:22:32,418 --> 00:22:36,522 over 19,000 feet, surveilling the earth below. 217 00:22:40,059 --> 00:22:44,296 Powerful binocular vision helps them zero in on their quarry. 218 00:22:47,166 --> 00:22:48,334 Target acquired. 219 00:22:52,705 --> 00:22:55,507 ♪ ♪ 220 00:22:55,641 --> 00:22:58,244 These white-backed vultures have their place 221 00:22:58,377 --> 00:22:59,511 in the pecking order. 222 00:23:02,848 --> 00:23:04,149 Protocol is key. 223 00:23:05,884 --> 00:23:08,687 Lappet-faced vultures will muscle their way in. 224 00:23:11,724 --> 00:23:14,493 Larger and more formidable than their cousins. 225 00:23:15,928 --> 00:23:19,732 Their dagger-like bills are made for ripping through tough hide. 226 00:23:25,904 --> 00:23:28,974 The white-backed vultures will get their turn soon enough. 227 00:23:31,277 --> 00:23:34,246 Using their less pointy meat cleaver bills. 228 00:23:36,382 --> 00:23:38,417 They go to town on the soft tissue. 229 00:23:40,819 --> 00:23:43,789 ♪ ♪ 230 00:23:47,293 --> 00:23:51,563 It might not seem like it, but vultures are big on hygiene. 231 00:23:53,932 --> 00:23:56,568 A bald head makes for easy cleaning. 232 00:24:04,510 --> 00:24:08,414 The last in line for the rotting buffet are the foot soldiers. 233 00:24:09,915 --> 00:24:12,885 Hooded vultures are the smallest of the lot. 234 00:24:14,420 --> 00:24:16,789 But they are specialists. 235 00:24:17,956 --> 00:24:22,528 They wield their narrow beaks like surgical knives, 236 00:24:22,661 --> 00:24:27,099 removing the tiniest bits of flesh and diving to the 237 00:24:27,232 --> 00:24:28,968 hardest to reach areas. 238 00:24:30,903 --> 00:24:35,407 This methodical clean-up service is invaluable to every single 239 00:24:35,541 --> 00:24:37,309 creature in the ecosystem. 240 00:24:43,215 --> 00:24:47,086 Their appetite for the dead, in no small part, helps to 241 00:24:47,219 --> 00:24:49,855 keep humans healthy and alive. 242 00:25:04,503 --> 00:25:08,674 248 miles off the eastern coast of Africa, 243 00:25:16,849 --> 00:25:20,686 wild monsoons lash the jungles of Madagascar. 244 00:25:28,427 --> 00:25:33,899 Rivers swell, and everyone does their best to 245 00:25:34,032 --> 00:25:35,434 wait out the rains. 246 00:25:45,477 --> 00:25:50,682 As the forest steams and the storms wake, lemur species 247 00:25:50,816 --> 00:25:54,953 all over the island now face a delicate problem. 248 00:25:57,556 --> 00:26:00,526 ♪ ♪ 249 00:26:15,574 --> 00:26:19,344 Their sultry conditions hatch plagues of disease-carrying 250 00:26:19,478 --> 00:26:26,718 mosquitoes and gut-churning intestinal worms. 251 00:26:30,689 --> 00:26:33,692 Every lemur is fair game for parasites. 252 00:26:35,294 --> 00:26:37,896 They need a fix, and fast. 253 00:26:40,365 --> 00:26:44,336 Enter Madagascar's giant millipede. 254 00:26:51,343 --> 00:26:54,480 ♪ ♪ 255 00:26:57,983 --> 00:27:04,289 These arthropods don't bite, and their defensive secretions 256 00:27:04,423 --> 00:27:06,558 are mostly harmless to humans. 257 00:27:09,361 --> 00:27:12,397 But to lemurs, they are precious. 258 00:27:13,599 --> 00:27:16,568 ♪ ♪ 259 00:27:19,104 --> 00:27:23,475 They smell weird and taste worse. 260 00:27:28,213 --> 00:27:30,215 But lemurs don't want to eat them. 261 00:27:32,684 --> 00:27:36,321 These unsuspecting insects are the answer 262 00:27:36,455 --> 00:27:37,756 to their pest problem. 263 00:27:44,730 --> 00:27:49,234 A quick nibble and the millipede secretes a nasty ooze. 264 00:27:52,905 --> 00:28:00,279 The toxic sludge would deter most, but not lemurs. 265 00:28:03,949 --> 00:28:07,286 The fluid contains benzoquinone, 266 00:28:08,987 --> 00:28:12,591 a great insecticide that repels mosquitoes. 267 00:28:21,967 --> 00:28:25,404 Mixed with their own saliva, lemurs rub the 268 00:28:25,537 --> 00:28:29,608 foul-smelling concoction all over their bodies. 269 00:28:30,642 --> 00:28:33,612 ♪ ♪ 270 00:28:34,613 --> 00:28:37,549 ♪ ♪ 271 00:28:38,817 --> 00:28:41,787 ♪ ♪ 272 00:28:43,922 --> 00:28:49,695 Like sour candy, the millipede's secretions make the lemurs drool, 273 00:28:52,364 --> 00:28:54,533 and their eyes glaze over. 274 00:28:57,102 --> 00:29:00,238 ♪ ♪ 275 00:29:05,811 --> 00:29:08,280 But there's something else at work here. 276 00:29:12,217 --> 00:29:15,354 ♪ ♪ 277 00:29:17,789 --> 00:29:20,759 ♪ ♪ 278 00:29:23,895 --> 00:29:27,966 The spaced-out expression says everything. 279 00:29:30,702 --> 00:29:35,440 The millipede juice may be good for lemurs' bodies, 280 00:29:35,574 --> 00:29:38,677 but it's also a strong narcotic. 281 00:29:43,115 --> 00:29:46,251 ♪ ♪ 282 00:29:49,321 --> 00:29:52,591 But all good trips must end sometime. 283 00:29:55,994 --> 00:29:58,864 An afternoon nap is the need of the hour. 284 00:30:01,433 --> 00:30:03,935 Millipedes it seems get nothing from this 285 00:30:04,069 --> 00:30:05,570 one-sided relationship. 286 00:30:07,406 --> 00:30:10,375 But at least they live to tell the tale, 287 00:30:10,509 --> 00:30:13,945 getting back to the business of being millipedes. 288 00:30:15,781 --> 00:30:19,217 Until the next mosquito apocalypse, when lemurs 289 00:30:19,351 --> 00:30:22,354 everywhere turn to these little psychoactive 290 00:30:22,487 --> 00:30:24,723 avengers for salvation. 291 00:30:26,124 --> 00:30:29,261 ♪ ♪ 292 00:30:34,866 --> 00:30:37,069 ♪ ♪ 293 00:30:38,170 --> 00:30:42,974 This primordial Southeast Asian jungle is home to one of 294 00:30:43,108 --> 00:30:45,844 nature's most far-out pairings. 295 00:30:48,947 --> 00:30:51,216 A flying rhinoceros. 296 00:30:52,918 --> 00:30:56,321 Lifelong soulmates with a strange method of 297 00:30:56,455 --> 00:30:57,823 sealing their union. 298 00:30:58,757 --> 00:31:01,727 ♪ ♪ 299 00:31:06,131 --> 00:31:09,267 ♪ ♪ 300 00:31:10,802 --> 00:31:13,338 Hornbills have one of the weirdest breeding 301 00:31:13,472 --> 00:31:15,607 strategies of any bird. 302 00:31:17,275 --> 00:31:19,544 It all starts ordinarily enough. 303 00:31:21,646 --> 00:31:26,551 The tallest trees in Borneo's forests are like arboreal cafes. 304 00:31:31,356 --> 00:31:34,860 Leafy hubs for hornbill flirtations. 305 00:31:36,862 --> 00:31:39,831 ♪ ♪ 306 00:31:42,701 --> 00:31:46,304 This guy is the envy of the whole jungle. 307 00:31:47,239 --> 00:31:50,442 ♪ ♪ 308 00:31:51,510 --> 00:31:56,648 As far as this female's concerned, his massive casque 309 00:31:56,782 --> 00:31:58,550 is massively attractive. 310 00:32:05,223 --> 00:32:10,095 Now he's got her attention, they can move on to 311 00:32:10,228 --> 00:32:11,596 a little courtship. 312 00:32:19,838 --> 00:32:24,276 Hornbills pair for life, so this girl is looking 313 00:32:24,409 --> 00:32:26,444 for her ultimate sidekick. 314 00:32:27,646 --> 00:32:30,215 She has one chance to make sure her chosen 315 00:32:30,348 --> 00:32:33,151 beau can go the distance. 316 00:32:36,121 --> 00:32:37,255 She wants a snack. 317 00:32:38,790 --> 00:32:41,460 Ever eager to please, the male presents her with 318 00:32:41,593 --> 00:32:43,528 the juiciest figs in town. 319 00:32:51,436 --> 00:32:54,272 And he's got more where that came from. 320 00:33:02,480 --> 00:33:06,251 He's not just a pretty face, he's also a provider. 321 00:33:09,387 --> 00:33:13,492 She's convinced this guy is her perfect co-pilot. 322 00:33:18,797 --> 00:33:22,467 Next, the smitten couple must cement their union. 323 00:33:24,269 --> 00:33:27,405 ♪ ♪ 324 00:33:30,575 --> 00:33:34,379 In the hornbill world, cement is the operative word. 325 00:33:44,122 --> 00:33:48,260 In one of the most unusual nesting practices amongst birds, 326 00:33:49,127 --> 00:33:53,265 the female imprisons herself within a tree cavity 327 00:33:53,398 --> 00:33:55,267 for almost two months. 328 00:33:57,202 --> 00:34:01,206 Surely her loving partner will get her out of this predicament. 329 00:34:02,607 --> 00:34:04,409 But it's quite the opposite. 330 00:34:05,510 --> 00:34:08,280 Hidden behind a wall of clay, droppings and 331 00:34:08,413 --> 00:34:12,417 saliva, she and her brood are safe from predators 332 00:34:12,550 --> 00:34:14,185 and the sweltering heat. 333 00:34:15,720 --> 00:34:18,690 ♪ ♪ 334 00:34:22,127 --> 00:34:26,164 The doting male delivers fruit through the hole in the tree. 335 00:34:42,080 --> 00:34:44,816 Cut off from the world and totally dependent on 336 00:34:44,950 --> 00:34:46,618 her partner for survival. 337 00:34:49,087 --> 00:34:52,357 The rigorous selection process that he was subjected 338 00:34:52,490 --> 00:34:54,726 to finally makes sense. 339 00:34:57,696 --> 00:35:00,932 He will bring her food nearly 20 times every day. 340 00:35:05,737 --> 00:35:09,040 The future of their genes depends completely on 341 00:35:09,174 --> 00:35:10,842 his ability to provide. 342 00:35:14,546 --> 00:35:17,015 The pair will repeat this process almost 343 00:35:17,148 --> 00:35:19,351 40 times throughout their lives, 344 00:35:23,822 --> 00:35:27,425 rendering this couple the tightest of fits. 345 00:35:37,235 --> 00:35:40,372 ♪ ♪ 346 00:35:42,340 --> 00:35:46,878 This planet has quite a flair for creating life in 347 00:35:47,012 --> 00:35:49,314 endlessly strange forms. 348 00:35:52,717 --> 00:35:55,620 But evolution keeps making crabs. 349 00:35:57,822 --> 00:35:59,658 And nobody knows why. 350 00:36:02,594 --> 00:36:05,630 ♪ ♪ 351 00:36:06,631 --> 00:36:10,668 In the last 250 million years, crab-like animals 352 00:36:10,802 --> 00:36:14,072 have evolved independently at least five times 353 00:36:14,205 --> 00:36:17,475 over from very different ancestors. 354 00:36:22,080 --> 00:36:26,184 But the reason crabs keep appearing may be because their 355 00:36:26,317 --> 00:36:30,789 body plan is so versatile when it comes to hiding 356 00:36:30,922 --> 00:36:32,157 from predators. 357 00:36:38,296 --> 00:36:42,734 So does a crab-like body make you an evolutionary rock star? 358 00:36:48,740 --> 00:36:52,343 Well fire urchins and sea anemones think so. 359 00:36:53,611 --> 00:36:56,614 Because once they've hooked up with certain crabs, 360 00:36:56,748 --> 00:37:01,553 these power couples will change each other's lives forever. 361 00:37:07,892 --> 00:37:11,796 Fire urchins are prickly deep-sea dwellers that 362 00:37:11,930 --> 00:37:13,898 are as dangerous as they look. 363 00:37:16,267 --> 00:37:18,570 Those spines are tipped with venom. 364 00:37:21,372 --> 00:37:23,942 That would be enough to ward off most species. 365 00:37:28,613 --> 00:37:30,882 But not the carrier crab. 366 00:37:32,450 --> 00:37:36,321 The crab's modified back legs have just one purpose. 367 00:37:40,225 --> 00:37:45,430 Whisking impressionable urchins away for the ride of their life. 368 00:37:48,867 --> 00:37:52,170 Coupled up and happy, they hit the road. 369 00:37:55,440 --> 00:37:59,277 The urchin's punked-up wig of venomous barbs protects 370 00:37:59,410 --> 00:38:00,979 the crab from predators. 371 00:38:04,582 --> 00:38:07,952 So he's free to indulge in his favorite foods. 372 00:38:09,521 --> 00:38:12,490 ♪ ♪ 373 00:38:16,027 --> 00:38:19,964 Like John and Yoko, this rock star couple have each 374 00:38:20,098 --> 00:38:22,333 other's backs no matter what. 375 00:38:28,139 --> 00:38:33,211 But rock star crabs can couple up in all kinds of ways. 376 00:38:35,613 --> 00:38:40,185 The boxer crab is more a glam rocker, spends most of its days 377 00:38:40,318 --> 00:38:42,887 attached to reefs in shallow waters. 378 00:38:48,560 --> 00:38:51,863 At these depths, it's vulnerable to birds, fish, 379 00:38:51,996 --> 00:38:54,732 octopus and even other crabs. 380 00:38:59,938 --> 00:39:01,372 Tough crowd to control. 381 00:39:06,144 --> 00:39:08,379 Luckily it's not alone. 382 00:39:09,881 --> 00:39:12,850 ♪ ♪ 383 00:39:15,386 --> 00:39:20,291 While these foxy white pom-poms may look like part of its eight limbs, 384 00:39:21,593 --> 00:39:25,396 they are in fact two venomous sea anemones, 385 00:39:25,530 --> 00:39:28,199 carried in its claws for protection. 386 00:39:29,968 --> 00:39:33,438 Dancing and weaving on its back legs, the boxer floats 387 00:39:33,571 --> 00:39:35,707 its white gloves as a warning. 388 00:39:40,478 --> 00:39:43,648 Stinging anyone who dares to come too close. 389 00:39:54,959 --> 00:39:59,063 In exchange for this defense, as the crab forages, 390 00:39:59,197 --> 00:40:02,900 the anemones are nourished by the crab's food scraps. 391 00:40:07,272 --> 00:40:10,408 ♪ ♪ 392 00:40:12,043 --> 00:40:16,014 In the life of evolutionary rock stars, the carrier and the 393 00:40:16,147 --> 00:40:21,452 boxer are two crabs that know the power of a great duet. 394 00:40:34,899 --> 00:40:40,104 Among the world of aquatic sidekicks, there is a kind of 395 00:40:40,238 --> 00:40:44,442 fish with a crude reputation as that annoying guest who 396 00:40:45,209 --> 00:40:46,778 never quite knows when to leave. 397 00:40:49,948 --> 00:40:53,151 In short, these fish suck. 398 00:40:53,284 --> 00:40:53,918 Big time. 399 00:41:06,164 --> 00:41:10,835 The remora's dorsal fin has adapted over time to become a 400 00:41:10,968 --> 00:41:16,607 suction disc, making them super clingy hitchhikers. 401 00:41:19,510 --> 00:41:23,081 With no air bladder to keep them afloat like normal fish, 402 00:41:24,048 --> 00:41:29,554 they depend on hospitable hosts to travel and to find food. 403 00:41:30,588 --> 00:41:34,292 But they've got to choose a ride that works for them. 404 00:41:35,626 --> 00:41:37,562 How about these whale sharks? 405 00:41:43,935 --> 00:41:47,405 Up to two dozen remoras crowd one whale shark. 406 00:41:50,274 --> 00:41:55,413 They snack on parasitic copepods that plague the giant fish. 407 00:41:57,014 --> 00:42:01,018 So whale sharks don't mind too much when it comes 408 00:42:01,152 --> 00:42:02,387 to giving them a lift. 409 00:42:08,026 --> 00:42:10,762 Then there's more sharky sharks. 410 00:42:13,097 --> 00:42:16,868 You'd think it would be harder to hold on to fast-moving hosts. 411 00:42:18,903 --> 00:42:19,937 But it's the opposite. 412 00:42:22,206 --> 00:42:26,210 The remora seals its suction disc against the shark's body. 413 00:42:33,551 --> 00:42:37,655 The faster the shark swims, the increasing water pressure 414 00:42:37,789 --> 00:42:40,625 amplifies the remora's suction seal. 415 00:42:42,493 --> 00:42:45,830 And if the host deems its guests a tad too annoying, 416 00:42:48,066 --> 00:42:49,834 they make for handy appetizers. 417 00:42:55,840 --> 00:42:58,743 Then there are these little suckers. 418 00:43:05,817 --> 00:43:09,654 For this species of remora, green sea turtles are 419 00:43:09,787 --> 00:43:11,155 the preferred superhost. 420 00:43:12,557 --> 00:43:15,526 ♪ ♪ 421 00:43:16,928 --> 00:43:19,430 Oh, something's stirring. 422 00:43:24,268 --> 00:43:26,771 It just happens to be the turtle's tummy. 423 00:43:28,973 --> 00:43:32,944 And the grateful bottom feeders suck up the offering. 424 00:43:39,750 --> 00:43:43,354 The planet is filled to the brim with, um, 425 00:43:43,488 --> 00:43:45,523 strange companionships. 426 00:43:46,657 --> 00:43:50,862 But remora like this take the sidekick thing 427 00:43:50,995 --> 00:43:52,864 to a whole new level. 428 00:43:53,898 --> 00:43:59,203 Because nature is never weirder than a toilet-trained fish.