1 00:00:08,542 --> 00:00:10,409 NARRATOR: The Ethiopian highlands. 2 00:00:13,614 --> 00:00:14,646 Lost world. 3 00:00:17,084 --> 00:00:19,551 Home to creatures found nowhere else. 4 00:00:24,425 --> 00:00:26,658 A monkey like no other. 5 00:00:28,996 --> 00:00:31,629 Sole survivor of a vanished tribe 6 00:00:31,665 --> 00:00:33,232 that once ruled the continent. 7 00:00:38,072 --> 00:00:42,241 And one of Africa's rarest predators, 8 00:00:42,243 --> 00:00:44,910 a high altitude rat-catching wolf. 9 00:00:47,715 --> 00:00:50,715 How do these extraordinary animals survive 10 00:00:50,751 --> 00:00:52,184 in this land of extremes? 11 00:00:55,289 --> 00:00:56,855 And how did they get here? 12 00:01:00,227 --> 00:01:04,062 To find out, we must travel to one of the most geologically 13 00:01:04,098 --> 00:01:06,131 violent places on earth. 14 00:01:08,903 --> 00:01:16,274 Where awesome forces create and destroy 15 00:01:16,343 --> 00:01:23,348 and ferocious rivals battle for dominance, 16 00:01:23,417 --> 00:01:29,121 changing the course of evolution on the roof of Africa. 17 00:01:34,829 --> 00:01:36,161 Hello. 18 00:01:36,230 --> 00:01:39,498 I'm David Schwimmer, and I play a paleontologist on television, 19 00:01:39,500 --> 00:01:42,100 but in real life, I'm a pretend naturalist. 20 00:01:42,136 --> 00:01:45,571 Behind me is a rat, one of the delightful creatures 21 00:01:45,706 --> 00:01:47,839 eaten in this episode of "Mysterious 22 00:01:47,875 --> 00:01:50,709 Planet, Roof of Africa." 23 00:01:50,778 --> 00:01:54,680 [eerie music] 24 00:02:05,759 --> 00:02:13,465 Dawn in the highlands of Ethiopia, 25 00:02:13,567 --> 00:02:17,269 a group of very unusual animals huddle together 26 00:02:17,338 --> 00:02:19,037 on the edge of the abyss. 27 00:02:23,210 --> 00:02:26,211 Gelada, not Italian ice cream but 28 00:02:26,280 --> 00:02:33,751 just as tasty, a species of monkey unlike any other 29 00:02:33,787 --> 00:02:39,791 found only here, an environment few can survive. 30 00:02:47,935 --> 00:02:52,303 After spending the night sleeping on a sheer cliff, 31 00:02:52,339 --> 00:02:55,974 their day begins by warming up in the sun. 32 00:02:56,043 --> 00:02:58,644 Upon inspection, they look to be hot air balloons. 33 00:03:02,082 --> 00:03:05,984 This is a family unit, a mature male 34 00:03:06,053 --> 00:03:10,989 with a magnificent cape of fur, several females, 35 00:03:11,124 --> 00:03:12,424 and their offspring. 36 00:03:17,264 --> 00:03:20,799 And these are young males, who hang out together until they 37 00:03:20,868 --> 00:03:21,800 get their own family. 38 00:03:25,806 --> 00:03:29,942 But all geladas share the same distinctive feature, 39 00:03:30,077 --> 00:03:35,347 an hourglass shaped patch of red skin on their chests, 40 00:03:35,416 --> 00:03:38,217 which gives them their unofficial name, 41 00:03:38,352 --> 00:03:39,618 the Bleeding Heart Baboon. 42 00:03:41,288 --> 00:03:43,822 Even in the highlands, political branding occurs. 43 00:03:47,427 --> 00:03:49,695 But geladas are not actually baboons. 44 00:03:51,565 --> 00:03:52,831 They are something unique. 45 00:03:56,903 --> 00:04:00,839 They are the sole survivor of an ancient group of monkeys 46 00:04:00,908 --> 00:04:02,341 that once dominated African. 47 00:04:05,312 --> 00:04:09,448 So how did they end up all alone in this high altitude realm? 48 00:04:14,722 --> 00:04:18,790 The Ethiopian highlands are one of the most dramatic landscapes 49 00:04:18,826 --> 00:04:24,796 in Africa, a vast, high altitude plateau spiked 50 00:04:24,931 --> 00:04:27,932 with dramatic peaks and split in half 51 00:04:28,002 --> 00:04:30,469 by a great shear-sided valley. 52 00:04:32,273 --> 00:04:35,606 At 2 miles above sea level, the air is thin 53 00:04:35,643 --> 00:04:38,610 and UV radiation fierce. 54 00:04:38,679 --> 00:04:42,681 And not a dermatologist available anywhere. 55 00:04:42,816 --> 00:04:48,219 The temperature can change over 70 degrees in a day 56 00:04:48,289 --> 00:04:51,323 from below freezing to almost 80. 57 00:04:54,628 --> 00:04:57,763 On the roof of Africa, it's summer every day 58 00:04:57,898 --> 00:05:01,032 and winter every night. 59 00:05:01,035 --> 00:05:02,768 So spring is around noonish. 60 00:05:08,976 --> 00:05:12,377 Once the gelada family has warmed up, 61 00:05:12,379 --> 00:05:14,346 it's time to begin their daily commute. 62 00:05:17,918 --> 00:05:22,487 Sometimes over 1,000 geladas join up and travel together. 63 00:05:24,925 --> 00:05:27,993 One of the largest gatherings of primates on Earth. 64 00:05:32,466 --> 00:05:36,335 And they're all after the same thing, a very 65 00:05:36,470 --> 00:05:38,403 unusual food for a monkey. 66 00:05:41,175 --> 00:05:41,873 Pancakes? 67 00:05:43,977 --> 00:05:45,610 Nope, grass. 68 00:05:48,816 --> 00:05:52,150 Geladas are the only monkey on Earth to feed 69 00:05:52,252 --> 00:05:54,119 almost entirely on grass. 70 00:05:57,023 --> 00:05:59,290 With nimble fingers, they carefully 71 00:05:59,326 --> 00:06:01,093 select the juiciest blades. 72 00:06:04,631 --> 00:06:08,567 But grass is low in nutrients, so geladas 73 00:06:08,569 --> 00:06:11,102 have to search for the richest meadows 74 00:06:11,105 --> 00:06:15,474 and spend up to 10 hours a day sitting, plucking, and chewing. 75 00:06:20,114 --> 00:06:24,816 A monkey with the diet of a cow, a conky. 76 00:06:27,587 --> 00:06:30,722 There were once many more like them spread across Africa, 77 00:06:30,791 --> 00:06:38,463 but now the gelada is the last of the grass-eating monkeys 78 00:06:38,465 --> 00:06:41,266 isolated on the roof of Africa. 79 00:06:51,678 --> 00:06:55,247 Geladas are not the only unique animals living up here. 80 00:06:58,018 --> 00:07:00,218 At their heart, the highlands are 81 00:07:00,220 --> 00:07:05,357 a great high altitude grassland, a savanna in the African sky. 82 00:07:07,094 --> 00:07:10,561 But there are no wildebeest or zebras here. 83 00:07:10,597 --> 00:07:13,965 It's too cold, and the air is too thin for Africa's 84 00:07:13,967 --> 00:07:14,666 large grazers. 85 00:07:17,037 --> 00:07:19,671 There is life, you just have to look a little closer. 86 00:07:22,509 --> 00:07:23,208 Rodents. 87 00:07:25,646 --> 00:07:31,049 In the Ethiopian highlands, 14 unique species of rat and mouse 88 00:07:31,051 --> 00:07:34,519 have evolved to take the place of more familiar herds. 89 00:07:34,521 --> 00:07:38,055 Not sure it's something to brag about, but how do 90 00:07:38,091 --> 00:07:41,125 they thrive where others can't? 91 00:07:41,161 --> 00:07:43,061 Ask the ones that live in my wall. 92 00:07:46,767 --> 00:07:49,468 Ah, by living underground. 93 00:07:52,773 --> 00:07:56,942 Their burrows protect them from the harsh climate 94 00:07:56,944 --> 00:08:07,152 and the vast grasslands sustain huge populations, 95 00:08:07,287 --> 00:08:13,291 up to 15,000 rodents per square mile, like the East Village. 96 00:08:18,165 --> 00:08:20,097 The largest rodent in the highlands 97 00:08:20,133 --> 00:08:25,637 is the giant mole rat, and he can talk. 98 00:08:25,706 --> 00:08:30,775 Not really, but they can weigh over 2 pounds 99 00:08:30,911 --> 00:08:33,712 and spend most of their time in their network of burrows. 100 00:08:36,850 --> 00:08:40,452 They only emerge to quickly grab a mouthful of food 101 00:08:40,454 --> 00:08:43,721 before disappearing again, similar to the North 102 00:08:43,757 --> 00:08:44,456 American teenager. 103 00:08:47,594 --> 00:08:51,195 It's wise for the rodents of the highlands to be careful though. 104 00:08:51,231 --> 00:08:51,930 Uh-oh. 105 00:08:57,371 --> 00:09:03,241 Where there are rodents, there are rodent eaters. 106 00:09:07,014 --> 00:09:17,756 The Ethiopian wolf, lean and lethal, 107 00:09:17,891 --> 00:09:23,628 perfectly adapted to the high altitude and harsh climate, 108 00:09:23,763 --> 00:09:25,897 and a specialist rodent hunter. 109 00:09:35,676 --> 00:09:37,175 But it's not always this easy. 110 00:09:39,446 --> 00:09:43,515 Wolves must be patient and cunning. 111 00:09:46,319 --> 00:09:53,124 The rats lairs can have multiple entrances, 112 00:09:53,259 --> 00:09:59,998 so the wolf must listen carefully to pinpoint its prey. 113 00:10:00,000 --> 00:10:01,566 It's a game of hide and squeak. 114 00:10:04,805 --> 00:10:08,707 It's long thin muzzle is perfect for poking into rodent burrows. 115 00:10:13,547 --> 00:10:16,915 And for blowing to flush its victims out. 116 00:10:18,485 --> 00:10:21,186 Fortunately, the rat doesn't have a brick house. 117 00:10:32,432 --> 00:10:34,232 Of all the rodents in the highlands, 118 00:10:34,367 --> 00:10:36,534 there is one the wolf loves best. 119 00:10:39,706 --> 00:10:46,411 A giant mole rat is a juicy feast, if you can catch one. 120 00:10:52,719 --> 00:10:54,919 Though the mole rat has poor eyesight, 121 00:10:54,955 --> 00:10:58,556 it has highly sensitive hearing and no toothbrush. 122 00:10:59,993 --> 00:11:03,461 The slightest movement, cue wolf, and it's gone. 123 00:11:04,397 --> 00:11:05,063 Damn it. 124 00:11:10,604 --> 00:11:13,038 But this ruthless hunter will not be denied. 125 00:11:14,841 --> 00:11:17,742 OK, that's-- we don't need to watch this. 126 00:11:17,877 --> 00:11:19,210 Yep, that's-- OK. 127 00:11:23,817 --> 00:11:30,088 Ethiopian wolves often hunt in the geladas meadows, 128 00:11:30,090 --> 00:11:32,757 but the wolves are such specialists rodent hunters 129 00:11:32,826 --> 00:11:35,426 they completely ignore the monkeys. 130 00:11:35,495 --> 00:11:36,194 Rude. 131 00:11:38,365 --> 00:11:40,932 And the geladas have no fear of the wolves. 132 00:11:44,504 --> 00:11:48,707 Two unique species living side by side on the roof of Africa. 133 00:11:52,079 --> 00:11:53,278 So how did they get here? 134 00:11:56,783 --> 00:11:59,116 To find out, we need to descend deep 135 00:11:59,152 --> 00:12:04,255 into the belly of the Earth where awesome forces 136 00:12:04,324 --> 00:12:06,858 are tearing Africa apart. 137 00:12:06,993 --> 00:12:08,093 Suspenseful beat. 138 00:12:12,999 --> 00:12:15,733 Right through the heart of the Ethiopian highlands 139 00:12:15,802 --> 00:12:21,005 is a great rift, sheer cliffs drop two 140 00:12:21,141 --> 00:12:23,908 miles down into a vast valley. 141 00:12:26,479 --> 00:12:32,016 And at its northern end is a sunken tortured landscape, 142 00:12:32,018 --> 00:12:35,553 the Afar Depression, gateway to hell. 143 00:12:40,360 --> 00:12:43,027 Here, we get a glimpse of the forces that have shaped 144 00:12:43,063 --> 00:12:44,796 life in this part of Africa. 145 00:12:49,035 --> 00:12:53,704 This is Erta Ale, one of the most remarkable 146 00:12:53,740 --> 00:12:55,039 volcanoes in the world. 147 00:12:57,511 --> 00:13:00,778 A bubbling cauldron of molten lava 148 00:13:00,814 --> 00:13:07,118 over 1,800 degrees, a window into what 149 00:13:07,187 --> 00:13:12,357 is going on right beneath Ethiopia and into my psyche. 150 00:13:14,928 --> 00:13:18,863 It all begins 40 million years ago 151 00:13:18,865 --> 00:13:21,332 when a massive column of magma starts 152 00:13:21,467 --> 00:13:27,172 melting its way towards the Earth's surface, a super plume. 153 00:13:29,409 --> 00:13:33,945 It pushes up the ground in a huge dome like a blister. 154 00:13:33,947 --> 00:13:34,946 Prom flashback. 155 00:13:36,716 --> 00:13:41,686 Lava oozes through cracks in the dome covering most of Ethiopia 156 00:13:41,688 --> 00:13:43,922 in a layer over a mile thick. 157 00:13:47,694 --> 00:13:52,163 And as the land continues to rise, huge volcanoes erupt. 158 00:14:02,075 --> 00:14:04,375 Today's highland's are the weathered remains 159 00:14:04,444 --> 00:14:05,977 of this volcanic dome. 160 00:14:10,083 --> 00:14:17,055 Over time, life takes hold, and in isolation 161 00:14:17,057 --> 00:14:19,256 evolves to become unique. 162 00:14:19,292 --> 00:14:19,991 Derek? 163 00:14:21,027 --> 00:14:21,693 Yes? 164 00:14:23,196 --> 00:14:24,162 Why the long face? 165 00:14:27,467 --> 00:14:30,268 The super plume lurking beneath Ethiopia 166 00:14:30,370 --> 00:14:36,274 pushes up these highlands, but it doesn't stop there. 167 00:14:36,276 --> 00:14:39,877 Next, it begins to tear the whole continent of Africa 168 00:14:39,946 --> 00:14:40,945 apart. 169 00:14:41,014 --> 00:14:41,713 Pushy plume. 170 00:14:43,550 --> 00:14:47,552 The colossal heat from below opens up a great rift 171 00:14:47,687 --> 00:14:52,489 in the Earth's crust spreading from the Afar Depression 172 00:14:52,525 --> 00:14:57,161 splitting the Ethiopian highlands in half 173 00:14:57,197 --> 00:15:01,699 and creating a dramatic Valley 300 miles long. 174 00:15:05,572 --> 00:15:09,907 At the bottom of this rift lives another monkey, 175 00:15:09,976 --> 00:15:13,745 which has played a leading role in the mystery of the gelada. 176 00:15:19,085 --> 00:15:23,320 A group of them is on the move across the hot, 177 00:15:23,356 --> 00:15:24,856 arid Rift Valley. 178 00:15:27,928 --> 00:15:33,864 At first glance, they look like geladas, 179 00:15:33,900 --> 00:15:35,533 but they are very different. 180 00:15:40,473 --> 00:15:42,440 These are Hamadryas baboons. 181 00:15:46,346 --> 00:15:48,980 The ancient Egyptians once worshipped them as gods. 182 00:15:50,684 --> 00:15:52,383 I mean, did you see their red butt? 183 00:15:55,221 --> 00:15:57,155 But those days are long gone. 184 00:15:58,692 --> 00:16:01,826 They must struggle to survive at the foot of the highlands. 185 00:16:05,498 --> 00:16:08,099 If geladas live on the roof of Africa, 186 00:16:08,168 --> 00:16:11,902 hamadryas live in the basement, like the average college 187 00:16:11,938 --> 00:16:12,637 graduate. 188 00:16:17,410 --> 00:16:22,647 There are no lush pastures here, water and food are scarce. 189 00:16:30,189 --> 00:16:33,791 Hamadryas are true baboons, and like all baboons, 190 00:16:33,827 --> 00:16:38,997 they are omnivores and will eat almost anything. 191 00:16:39,132 --> 00:16:42,667 This environment is too harsh to be fussy. 192 00:16:42,669 --> 00:16:44,869 Is he eating what I think he's eating? 193 00:16:45,004 --> 00:16:45,670 Ugh. 194 00:16:48,741 --> 00:16:52,810 They are constantly on the move foraging for any scraps 195 00:16:52,812 --> 00:16:55,646 of food or poop they can find. 196 00:16:58,151 --> 00:17:03,421 The alpha male keeps a careful eye on his family, 197 00:17:03,556 --> 00:17:04,622 especially the females. 198 00:17:08,128 --> 00:17:11,896 It's dangerous to be so spread out in the open, 199 00:17:11,965 --> 00:17:13,664 yet they have to move to survive. 200 00:17:16,536 --> 00:17:21,639 But he knows where he is going, and he leads his family 201 00:17:21,641 --> 00:17:31,516 to a special place with deep pools of clear water and palm 202 00:17:31,518 --> 00:17:33,551 trees laden with fruit. 203 00:17:36,723 --> 00:17:39,723 Where did this oasis come from? 204 00:17:39,759 --> 00:17:41,159 Is this a baboon mirage? 205 00:17:43,363 --> 00:17:45,996 These are the Dollol hot springs, 206 00:17:46,032 --> 00:17:47,432 say that fast three times. 207 00:17:49,202 --> 00:17:56,140 The water is 113 degrees, a baboon day spa, 208 00:17:56,275 --> 00:17:59,243 heated by the same fury beneath the earth that created 209 00:17:59,378 --> 00:18:08,219 the highlands, and a reminder of the powerful forces 210 00:18:08,288 --> 00:18:10,888 that have shaped all life here. 211 00:18:17,797 --> 00:18:21,365 The super plume that lurks below Ethiopia 212 00:18:21,501 --> 00:18:24,769 has created two very different habitats 213 00:18:24,771 --> 00:18:26,471 for two very different monkeys. 214 00:18:29,909 --> 00:18:33,577 Although they live separate lives today, millions of years 215 00:18:33,646 --> 00:18:38,716 ago, their ancestors clashed in a desperate struggle 216 00:18:38,851 --> 00:18:42,053 for survival on Africa's grasslands. 217 00:18:44,991 --> 00:18:48,425 One tribe dominated, while the other was 218 00:18:48,495 --> 00:18:49,961 almost wiped from the earth. 219 00:18:58,371 --> 00:19:01,872 High on the roof of Africa, a troupe of geladas 220 00:19:01,875 --> 00:19:05,142 are doing what they spend almost all their time doing, 221 00:19:05,178 --> 00:19:08,379 eating grass, and calculus. 222 00:19:12,519 --> 00:19:15,886 It's a smart evolutionary strategy, 223 00:19:15,955 --> 00:19:19,824 though grass is nutrient poor, there is so much of it they 224 00:19:19,959 --> 00:19:25,562 don't need to fight for food, so their society 225 00:19:25,598 --> 00:19:27,398 is stable and peaceful. 226 00:19:30,503 --> 00:19:34,839 Huge groups mixed together happily and violence is rare. 227 00:19:38,377 --> 00:19:39,911 But there are exceptions. 228 00:19:43,650 --> 00:19:47,051 As the females of the family graze, the alpha male 229 00:19:47,186 --> 00:19:49,854 is keeping a close eye out for trouble. 230 00:19:53,993 --> 00:19:54,926 And here it comes. 231 00:19:57,330 --> 00:20:02,933 A gang of young bachelor males, troublemakers on the edge 232 00:20:02,969 --> 00:20:06,870 of society, especially if they've been drinking, 233 00:20:06,940 --> 00:20:10,241 waiting and watching for an opportunity. 234 00:20:12,045 --> 00:20:14,678 It starts with the stare down now. 235 00:20:14,714 --> 00:20:16,614 Oh, I have been here before. 236 00:20:21,621 --> 00:20:24,321 The alpha male warns the intruders 237 00:20:24,357 --> 00:20:28,225 first with an eyebrow raise. 238 00:20:28,228 --> 00:20:29,026 You talking to me? 239 00:20:30,330 --> 00:20:33,764 Then by rolling back his top lip and exposing 240 00:20:33,899 --> 00:20:35,499 his huge canine teeth. 241 00:20:36,836 --> 00:20:37,969 I would have opened with that one. 242 00:20:40,373 --> 00:20:42,439 The largest in proportion to body 243 00:20:42,475 --> 00:20:48,245 size of any mammal on Earth, but his challengers 244 00:20:48,314 --> 00:20:49,647 are not scared off that easily. 245 00:20:55,421 --> 00:20:58,989 The bachelors charge the alpha and appear 246 00:20:59,025 --> 00:21:00,091 to have him on the run. 247 00:21:04,196 --> 00:21:10,735 But it's a trick, he's leading them away from his family. 248 00:21:10,870 --> 00:21:11,535 Smart monkey. 249 00:21:15,541 --> 00:21:17,475 Not that they seem very concerned. 250 00:21:20,513 --> 00:21:21,478 Why? 251 00:21:21,581 --> 00:21:23,547 Because it's mostly all for show. 252 00:21:26,686 --> 00:21:30,421 The bachelor males are challenging the alpha, 253 00:21:30,490 --> 00:21:32,423 but not in a battle to the death. 254 00:21:34,560 --> 00:21:35,993 It's more about showing off. 255 00:21:41,701 --> 00:21:45,569 All of the females in each family group are related, 256 00:21:45,705 --> 00:21:47,371 and they call the shots. 257 00:21:49,975 --> 00:21:52,509 If this alpha male can't demonstrate 258 00:21:52,545 --> 00:21:55,178 he's fit enough to defend the family, 259 00:21:55,214 --> 00:21:56,347 they will choose another. 260 00:22:02,855 --> 00:22:07,658 This combination of abundant food and a stable social system 261 00:22:07,660 --> 00:22:10,827 was a winning formula for the geladas ancestors 262 00:22:10,863 --> 00:22:12,029 when they first evolved. 263 00:22:15,735 --> 00:22:18,135 And their rise was a direct result 264 00:22:18,270 --> 00:22:21,338 of the violent geological forces that lurk 265 00:22:21,374 --> 00:22:23,274 below this part of the world. 266 00:22:30,550 --> 00:22:35,686 4 million years ago, Africa's climate is much wetter 267 00:22:35,688 --> 00:22:41,224 and lush forest is widespread, but again, 268 00:22:41,260 --> 00:22:43,027 the mantle plume is stirring. 269 00:22:45,231 --> 00:22:50,501 As the Rift Valley continues to unzip East Africa, 270 00:22:50,570 --> 00:22:53,771 mountains rise along its edge and the climate 271 00:22:53,906 --> 00:22:56,173 of the whole continent changes. 272 00:22:59,779 --> 00:23:04,248 The high terrain creates a rainshadow and East Africa 273 00:23:04,317 --> 00:23:05,649 begins to dry out. 274 00:23:08,354 --> 00:23:12,189 Rainforests shrink and grasslands grow. 275 00:23:15,328 --> 00:23:17,594 A group of monkeys called therapithicus 276 00:23:17,663 --> 00:23:19,163 take advantage of this change. 277 00:23:22,735 --> 00:23:26,403 They evolve to become specialist grass eaters 278 00:23:26,472 --> 00:23:28,272 and spread across Africa. 279 00:23:31,844 --> 00:23:34,011 Some grow as big as gorillas. 280 00:23:40,119 --> 00:23:45,222 One species even colonizes the remote Ethiopian highlands 281 00:23:45,291 --> 00:23:47,258 and becomes today's geladas. 282 00:23:50,563 --> 00:23:52,763 The peaceful, grass eating monkeys 283 00:23:52,898 --> 00:23:56,600 dominate Africa's savanna for over a million years. 284 00:24:01,040 --> 00:24:04,508 Yet, geladas are now the last of them 285 00:24:04,643 --> 00:24:07,311 confined to their harsh sanctuary in the clouds. 286 00:24:10,817 --> 00:24:14,051 What brought the reign of the therapithicus monkeys 287 00:24:14,120 --> 00:24:14,819 to an end? 288 00:24:16,823 --> 00:24:23,727 One of the key suspects lives two miles below, a rival monkey 289 00:24:23,863 --> 00:24:26,864 tribe that has forsaken living peacefully 290 00:24:26,933 --> 00:24:29,667 and chosen the path of war. 291 00:24:35,875 --> 00:24:39,009 The violent volcanic forces beneath Ethiopia 292 00:24:39,011 --> 00:24:42,146 have forged a unique and dramatic landscape. 293 00:24:45,918 --> 00:24:49,553 These vertical cliffs are ancient fault lines 294 00:24:49,622 --> 00:24:56,894 along the floor of the Rift Valley, an ideal sanctuary 295 00:24:56,963 --> 00:24:58,295 for hamadryas baboons. 296 00:25:02,968 --> 00:25:05,435 Their family structure is the opposite 297 00:25:05,505 --> 00:25:09,173 of the female dominated geladas in the highlands above. 298 00:25:13,813 --> 00:25:18,982 The alpha male is firmly in control, 299 00:25:19,018 --> 00:25:21,351 and he employs a carrot and stick 300 00:25:21,420 --> 00:25:23,254 approach to ruling the family. 301 00:25:26,259 --> 00:25:33,797 He can be kind and helps look after the young, 302 00:25:33,933 --> 00:25:37,334 but any females that dare to wander from his sight 303 00:25:37,403 --> 00:25:40,204 are ruthlessly dealt with. 304 00:25:40,339 --> 00:25:43,107 See, that's the definition of harassment. 305 00:25:48,347 --> 00:25:51,148 Luckily for this family there's little need to stray. 306 00:25:56,756 --> 00:26:01,091 The geothermal oasis provides plenty of food and water. 307 00:26:03,563 --> 00:26:06,830 They can stay close to each other and the alpha male 308 00:26:06,832 --> 00:26:09,033 is less concerned about wayward females. 309 00:26:12,905 --> 00:26:17,107 But like Ethiopia itself, violent forces 310 00:26:17,109 --> 00:26:22,079 bubble just below the surface always threatening to erupt. 311 00:26:25,318 --> 00:26:26,784 Lookouts sound the alarm. 312 00:26:30,590 --> 00:26:32,790 War is on its way. 313 00:26:36,528 --> 00:26:38,929 A rival clan wants what they have. 314 00:26:44,737 --> 00:26:49,640 The alpha males hurl themselves into battle, apes of wrath. 315 00:26:52,044 --> 00:26:55,679 Ordered society turns to chaos, like Twitter. 316 00:27:06,359 --> 00:27:11,495 The family leader is cornered by snarling rivals, 317 00:27:11,630 --> 00:27:14,131 like peer reviews gone horribly wrong. 318 00:27:27,379 --> 00:27:28,779 But there is method to the madness. 319 00:27:33,119 --> 00:27:36,086 The raiders have a clear strategic goal. 320 00:27:38,190 --> 00:27:39,757 They're not after food or water. 321 00:27:42,395 --> 00:27:44,061 They're after females. 322 00:27:55,274 --> 00:28:05,148 This is a mass kidnapping, and when 323 00:28:05,184 --> 00:28:13,223 they have what they came for, they retreat, 324 00:28:13,225 --> 00:28:17,828 leaving the hot springs clan licking their wounds 325 00:28:17,963 --> 00:28:20,297 and minus several young females. 326 00:28:24,636 --> 00:28:28,772 Such violence couldn't be more different from gelada society, 327 00:28:28,808 --> 00:28:33,477 but is typical of baboons, and is a key part of their success. 328 00:28:37,616 --> 00:28:42,252 It was baboons that out competed the geladas ancestors in all 329 00:28:42,387 --> 00:28:46,056 but the highlands of Ethiopia to become the dominant monkey 330 00:28:46,058 --> 00:28:48,659 of Africa's grasslands, so at least they've 331 00:28:48,794 --> 00:28:50,594 got that going for them. 332 00:28:50,663 --> 00:28:53,163 But again, it was geology that provided the catalyst. 333 00:28:56,135 --> 00:29:02,405 Baboons evolved in the far South of Africa at a time 334 00:29:02,441 --> 00:29:05,875 when impenetrable rain forest stretched right 335 00:29:05,911 --> 00:29:07,344 across the continent's center. 336 00:29:09,081 --> 00:29:13,684 But as the Great Rift spreads South creating new grasslands 337 00:29:13,686 --> 00:29:17,487 for the ancestors of the gelada, it also 338 00:29:17,523 --> 00:29:23,761 opens up a route North for the baboons, a corridor 3 and 1/2 339 00:29:23,896 --> 00:29:28,632 thousand miles long, an invasion route. 340 00:29:35,774 --> 00:29:38,775 The aggressive, adaptable baboons rapidly 341 00:29:38,844 --> 00:29:41,511 move up the Rift Valley and enter the realm 342 00:29:41,547 --> 00:29:44,114 of the peaceful grass-eating monkeys, 343 00:29:44,183 --> 00:29:47,651 like a high school bully in the hall, 344 00:29:47,786 --> 00:29:50,354 and soon begin to outcompete them. 345 00:29:57,396 --> 00:29:59,563 And there are more arrivals on the way. 346 00:30:02,468 --> 00:30:06,336 An evolutionary explosion of grazing mammals 347 00:30:06,372 --> 00:30:11,808 also spreads North along the Rift corridor 348 00:30:11,844 --> 00:30:14,111 and soon dominates the savanna. 349 00:30:21,086 --> 00:30:24,021 Even the climate turns against the therapithicus 350 00:30:24,023 --> 00:30:25,555 against monkeys. 351 00:30:25,591 --> 00:30:26,790 Et tu, climate? 352 00:30:28,360 --> 00:30:32,362 Africa dries out so much that lush, green pastures 353 00:30:32,398 --> 00:30:34,398 become arid scrub lands. 354 00:30:37,303 --> 00:30:43,706 Adaptable baboons can still find food, 355 00:30:43,742 --> 00:30:47,377 but one by one, the grass-eating monkeys become extinct. 356 00:30:48,848 --> 00:30:50,614 I guess that's the law of the savanna. 357 00:30:55,454 --> 00:30:58,388 Leaving just a single species isolated 358 00:30:58,424 --> 00:30:59,556 in a mountain fortress. 359 00:31:03,462 --> 00:31:07,363 The geladas high altitude kingdom is too harsh 360 00:31:07,399 --> 00:31:14,004 for baboons or large grazer's to endure, 361 00:31:14,139 --> 00:31:17,874 so the Ethiopian highlands become the last stand 362 00:31:17,910 --> 00:31:19,176 of the grass-eating monkeys. 363 00:31:21,513 --> 00:31:22,512 Passive aggressive victory. 364 00:31:28,687 --> 00:31:35,292 Another day in the Ethiopian highlands, the rising sun 365 00:31:35,294 --> 00:31:42,032 bringing relief from the frozen night, 366 00:31:42,167 --> 00:31:44,935 but Ethiopian wolves are used to the cold. 367 00:31:49,375 --> 00:31:52,976 They may hunt alone, but like all wolves, 368 00:31:53,111 --> 00:31:54,778 they rely on the pack to survive. 369 00:31:58,450 --> 00:32:02,051 Their day always begins with social bonding. 370 00:32:02,087 --> 00:32:03,320 Oh, yeah, can you get that? 371 00:32:03,322 --> 00:32:04,121 Thank you. 372 00:32:04,123 --> 00:32:04,821 Thank you. 373 00:32:06,892 --> 00:32:08,458 And the newest members of the pack 374 00:32:08,593 --> 00:32:11,595 emerge from their den to greet the sun. 375 00:32:11,597 --> 00:32:12,663 Yeah, that's a lot of cuteness. 376 00:32:15,167 --> 00:32:19,069 While the babysitter guards the pups, the rest of the pack 377 00:32:19,138 --> 00:32:20,203 goes out on patrol. 378 00:32:23,442 --> 00:32:26,609 Hey, pups, you'll be kings of all that you survey. 379 00:32:26,645 --> 00:32:28,378 The bad news, all you eat are rats. 380 00:32:34,520 --> 00:32:38,221 DNA analysis has revealed the Ethiopian wolf's 381 00:32:38,257 --> 00:32:42,960 closest ancestor is the greywolf of Europe and Asia. 382 00:32:45,998 --> 00:32:48,231 How did they end up in the highlands of Ethiopia? 383 00:32:49,434 --> 00:32:50,100 Teleport? 384 00:32:52,671 --> 00:32:56,073 Simple, just like this. 385 00:32:57,609 --> 00:33:00,310 They traveled across frozen grasslands. 386 00:33:04,583 --> 00:33:08,117 After being torn apart by volcanic fire, 387 00:33:08,153 --> 00:33:11,188 Ethiopia goes through one more dramatic change. 388 00:33:18,163 --> 00:33:20,230 This time because of ice. 389 00:33:22,668 --> 00:33:26,469 100,000 years ago the Earth is in the grip 390 00:33:26,538 --> 00:33:28,705 of its last major Ice Age. 391 00:33:32,177 --> 00:33:35,212 Frozen grasslands stretch from the Arctic 392 00:33:35,347 --> 00:33:40,283 to Northern Africa allowing the Ethiopian wolf's 393 00:33:40,419 --> 00:33:45,989 ancestor to simply walk its way onto a whole new continent. 394 00:33:54,867 --> 00:33:57,700 After another successful hunting trip, 395 00:33:57,770 --> 00:34:02,238 the pack returns to the den with bellies full of rodents, 396 00:34:02,307 --> 00:34:09,645 hopefully dead, which they regurgitate for their young. 397 00:34:09,681 --> 00:34:11,047 Oh, who's picking these clips? 398 00:34:11,116 --> 00:34:11,815 Ugh. 399 00:34:13,685 --> 00:34:15,651 In just a few months, the pups will 400 00:34:15,687 --> 00:34:18,054 be hunting rats for themselves. 401 00:34:18,090 --> 00:34:18,789 Yeah. 402 00:34:21,693 --> 00:34:23,259 But for now, they're still enjoying 403 00:34:23,295 --> 00:34:25,929 the best of both worlds, fresh rats 404 00:34:26,064 --> 00:34:29,266 and fresh milk, rat milkshakes. 405 00:34:29,401 --> 00:34:31,334 Awesome. 406 00:34:31,336 --> 00:34:35,005 It's good they're well-fed because every Ethiopian wolf 407 00:34:35,140 --> 00:34:36,039 pup is precious. 408 00:34:38,544 --> 00:34:42,446 There are less than 500 of their species left on the planet. 409 00:34:47,152 --> 00:34:50,353 20,000 years ago, the world begins 410 00:34:50,389 --> 00:34:53,123 to thaw as the Ice Age recedes. 411 00:34:56,895 --> 00:35:00,096 The wolf's habitat disappears everywhere 412 00:35:00,132 --> 00:35:04,701 except in the Ethiopian highlands, 413 00:35:04,703 --> 00:35:07,237 a frozen island in a warm sea. 414 00:35:11,176 --> 00:35:15,712 Today, Ethiopian wolves have become such specialist rodent 415 00:35:15,847 --> 00:35:19,850 hunters, they can't survive on anything else, 416 00:35:19,985 --> 00:35:21,351 like me and ramen. 417 00:35:22,788 --> 00:35:26,322 And since their prey lives nowhere else, 418 00:35:26,391 --> 00:35:27,757 the wolves are stranded here. 419 00:35:30,395 --> 00:35:32,996 The better they get at hunting rodents, 420 00:35:32,998 --> 00:35:36,666 the more they lock themselves deeper into a desperate battle 421 00:35:36,801 --> 00:35:37,467 for survival. 422 00:35:41,874 --> 00:35:45,675 One of the rarest carnivores on Earth, 423 00:35:45,677 --> 00:35:50,547 too specialized for its own good, which ironically might 424 00:35:50,682 --> 00:35:52,115 be a play by Virginia Woolf. 425 00:35:57,355 --> 00:35:59,956 At the foot of the Ethiopian highlands, 426 00:35:59,958 --> 00:36:02,826 the hamadryas family is once again on the move. 427 00:36:06,865 --> 00:36:10,033 As they walk, they send visual signals to one another. 428 00:36:12,504 --> 00:36:20,510 A red swollen behind signals that a male is a mature adult, 429 00:36:20,512 --> 00:36:23,112 or that a female is ready to mate. 430 00:36:23,148 --> 00:36:23,847 Well, hello. 431 00:36:26,385 --> 00:36:28,251 Since they're always on the move, 432 00:36:28,320 --> 00:36:32,255 having these signals on their rear makes them easy to see. 433 00:36:32,324 --> 00:36:33,023 No kidding. 434 00:36:34,726 --> 00:36:37,794 It's a feature shared by all baboons 435 00:36:37,929 --> 00:36:39,229 and a couple of guys I know. 436 00:36:44,236 --> 00:36:47,470 This Rift Valley helped their ancestors become 437 00:36:47,539 --> 00:36:53,542 the dominant monkey of Africa's grasslands 438 00:36:53,579 --> 00:36:56,813 by invading the realm of the grass-eating therapithicus 439 00:36:56,815 --> 00:37:04,888 monkeys and driving them from the earth, 440 00:37:05,023 --> 00:37:06,489 except for one species. 441 00:37:11,963 --> 00:37:17,634 Two miles above, the geladas are safe in their high altitude 442 00:37:17,636 --> 00:37:21,438 sanctuary, but one mystery remains. 443 00:37:23,342 --> 00:37:25,909 Why do they have that distinctive red patch 444 00:37:25,911 --> 00:37:29,012 on their chests, the bleeding heart? 445 00:37:31,316 --> 00:37:33,650 Geladas are not baboons. 446 00:37:33,719 --> 00:37:37,854 They are the last of the grass-eating monkeys, 447 00:37:37,989 --> 00:37:40,990 and since they spend their days sitting down, 448 00:37:41,059 --> 00:37:44,861 it's no use having their sexual signals on their behinds. 449 00:37:44,863 --> 00:37:46,863 Oh, I get it now. 450 00:37:46,865 --> 00:37:49,865 So they wear them on their chests, 451 00:37:49,901 --> 00:37:51,468 where everyone can see them. 452 00:37:51,603 --> 00:37:52,269 Right. 453 00:37:57,109 --> 00:38:01,211 Their highland home was created by a super plume of magma 454 00:38:01,346 --> 00:38:07,283 beneath Ethiopia, which uplifted a vast volcanic dome 455 00:38:07,352 --> 00:38:10,287 and created a refuge for a small group 456 00:38:10,422 --> 00:38:12,088 of tough and unique animals. 457 00:38:15,961 --> 00:38:18,361 Free of competitors and wet enough 458 00:38:18,430 --> 00:38:22,832 to nourish lush pastures, the Ethiopian highlands became 459 00:38:22,967 --> 00:38:25,235 a sanctuary in the African sky. 460 00:38:29,841 --> 00:38:34,077 The last place these magnificent monkeys can call home. 461 00:38:37,149 --> 00:38:39,983 Their ancestors were driven from the lowlands 462 00:38:39,985 --> 00:38:46,022 by hordes of baboons, but there is another primate 463 00:38:46,058 --> 00:38:48,058 that helped wipe them out. 464 00:38:48,193 --> 00:38:48,858 What? 465 00:38:48,993 --> 00:38:49,659 Who? 466 00:38:52,597 --> 00:38:53,863 Us. 467 00:38:53,865 --> 00:38:54,964 Oh, OK, sorry. 468 00:38:56,334 --> 00:38:59,135 At the same time that baboons were expanding 469 00:38:59,171 --> 00:39:04,140 into the African grasslands, the ancestors of our own species 470 00:39:04,142 --> 00:39:09,345 came down from the trees and migrated up the Rift Valley. 471 00:39:09,414 --> 00:39:13,550 Fossil evidence shows they preyed on the geladas ancestors 472 00:39:13,685 --> 00:39:14,451 along the way. 473 00:39:20,425 --> 00:39:23,092 The decline of their kind coincided 474 00:39:23,161 --> 00:39:25,595 with the rise of ours. 475 00:39:34,906 --> 00:39:38,007 And today, the grass-eating monkeys face a new invasion. 476 00:39:41,847 --> 00:39:47,383 Ethiopia is one of the fastest growing countries in the world, 477 00:39:47,486 --> 00:39:53,656 home to over 100 million people, and 478 00:39:53,658 --> 00:39:55,458 the highlands contains some of the most 479 00:39:55,494 --> 00:39:56,960 fertile land in Africa. 480 00:40:01,333 --> 00:40:04,868 Now, the most remote reaches of the geladas kingdom 481 00:40:04,870 --> 00:40:07,804 are being colonized by humans, and 482 00:40:07,906 --> 00:40:10,206 the grass-eating monkeys are once again being 483 00:40:10,208 --> 00:40:11,741 driven from their pastures. 484 00:40:15,514 --> 00:40:18,181 I have opposable thumbs, why are you messing with me? 485 00:40:23,688 --> 00:40:25,054 Ah, I'm out of here. 486 00:40:33,031 --> 00:40:36,366 As the day draws to an end, the temperature 487 00:40:36,368 --> 00:40:37,600 quickly begins to drop. 488 00:40:41,907 --> 00:40:47,177 Winter is coming, as it does every night up here. 489 00:40:51,283 --> 00:40:53,983 The geladas return to their sleeping cliffs. 490 00:41:03,795 --> 00:41:10,399 The last of their kind, alone with their bleeding 491 00:41:10,469 --> 00:41:15,705 hearts on the roof of Africa.