1 00:00:01,700 --> 00:00:04,900 What would happen? 2 00:00:02,900 --> 00:00:07,967 If every human being on earth 3 00:00:05,967 --> 00:00:08,434 Disappeared? 4 00:00:08,434 --> 00:00:16,301 [music] 5 00:00:16,301 --> 00:00:18,900 At some point in the future, 6 00:00:18,900 --> 00:00:20,034 This could be the fate 7 00:00:20,034 --> 00:00:23,900 Of our planet. 8 00:00:23,900 --> 00:00:25,201 This isn't the story 9 00:00:25,201 --> 00:00:29,034 Of how we might vanish. 10 00:00:29,034 --> 00:00:31,467 It is the story of what happens 11 00:00:31,467 --> 00:00:54,800 To the world we leave behind. 12 00:00:54,800 --> 00:00:56,434 The disappearance of humans 13 00:00:56,434 --> 00:01:01,767 May seem like science fiction, 14 00:01:01,767 --> 00:01:02,234 But eventually, 15 00:01:02,234 --> 00:01:06,833 There will come a day like this; 16 00:01:06,833 --> 00:01:07,900 A day when people 17 00:01:07,900 --> 00:01:16,100 No longer walk the earth. 18 00:01:16,167 --> 00:01:16,900 it's no great stretch 19 00:01:16,900 --> 00:01:18,601 To imagine humans disappearing 20 00:01:18,601 --> 00:01:20,000 From the face of the earth. 21 00:01:20,000 --> 00:01:21,700 Every generation has its tales 22 00:01:21,700 --> 00:01:25,134 Of Armageddon or apocalypse. 23 00:01:25,267 --> 00:01:26,401 We're the first generation 24 00:01:26,401 --> 00:01:27,067 That could, 25 00:01:27,067 --> 00:01:28,568 By deliberate actions, 26 00:01:28,568 --> 00:01:33,634 Cause its own doom. 27 00:01:33,634 --> 00:01:35,534 What will life be like? 28 00:01:35,534 --> 00:01:40,134 After people? 29 00:01:40,134 --> 00:01:43,067 We're tantalized by our myths 30 00:01:43,067 --> 00:01:48,100 About our own destruction, 31 00:01:48,100 --> 00:01:49,100 But also tantalized 32 00:01:49,100 --> 00:01:50,134 By the notion, 33 00:01:50,134 --> 00:01:51,367 "hey, maybe it's the turn 34 00:01:51,367 --> 00:01:54,234 Of someone else." 35 00:01:54,234 --> 00:01:55,234 What will they do? 36 00:01:55,234 --> 00:02:01,034 If we're gone? 37 00:02:01,034 --> 00:02:01,800 What will the earth do? 38 00:02:01,800 --> 00:02:05,568 When I'm gone? 39 00:02:05,568 --> 00:02:06,501 It's the most natural question 40 00:02:06,501 --> 00:02:14,800 In the world. 41 00:02:14,800 --> 00:02:19,100 [alarm buzzing] 42 00:02:19,100 --> 00:02:30,867 Time has run out for man. 43 00:02:30,867 --> 00:02:36,100 Our hold on the planet is over. 44 00:02:42,201 --> 00:02:44,700 Welcome to earth, 45 00:02:44,700 --> 00:02:57,301 Population zero. 46 00:02:57,301 --> 00:03:00,367 Within hours after we're gone, 47 00:03:00,367 --> 00:03:01,501 Lights start going out 48 00:03:01,501 --> 00:03:08,501 Around the world. 49 00:03:08,501 --> 00:03:10,401 More than 70 percent of power 50 00:03:10,401 --> 00:03:11,800 In the United States 51 00:03:11,800 --> 00:03:12,967 Is generated by the burning 52 00:03:12,967 --> 00:03:17,267 Of fossil fuels. 53 00:03:17,267 --> 00:03:19,100 the plant will only continue 54 00:03:19,100 --> 00:03:20,301 To produce electricity 55 00:03:20,301 --> 00:03:21,401 As long as the fuel 56 00:03:21,401 --> 00:03:25,267 Takes to be consumed. 57 00:03:25,334 --> 00:03:26,501 If there's no one around 58 00:03:26,501 --> 00:03:27,967 To provide the new fuel 59 00:03:27,967 --> 00:03:29,967 Into the generating plant, 60 00:03:29,967 --> 00:03:31,301 Then it'll be quite quick 61 00:03:31,301 --> 00:03:33,501 Before the lights 62 00:03:33,501 --> 00:03:34,534 Start going out in cities 63 00:03:34,534 --> 00:03:38,733 All over the world. 64 00:03:38,867 --> 00:03:39,733 Nuclear power plants 65 00:03:39,733 --> 00:03:42,700 Are unlikely to melt down. 66 00:03:42,700 --> 00:03:43,534 The average reactor 67 00:03:43,534 --> 00:03:44,568 Holds enough fuel 68 00:03:44,568 --> 00:03:47,367 To keep running for two years. 69 00:03:47,367 --> 00:03:48,334 But without humans 70 00:03:48,334 --> 00:03:49,467 Consuming the power 71 00:03:49,467 --> 00:03:51,867 Generated by the plant, 72 00:03:51,867 --> 00:03:53,501 The reactors will automatically 73 00:03:53,501 --> 00:03:56,568 Shut down into a safe mode 74 00:03:56,568 --> 00:04:00,867 In as little as two days. 75 00:04:00,867 --> 00:04:02,167 even wind generation 76 00:04:02,167 --> 00:04:04,501 Can't last forever. 77 00:04:04,501 --> 00:04:06,767 The turbines require bearings 78 00:04:06,767 --> 00:04:07,601 And lubrication 79 00:04:07,601 --> 00:04:08,401 Of those bearings 80 00:04:08,401 --> 00:04:11,967 In order to keep operating. 81 00:04:11,967 --> 00:04:12,668 If there's no one around 82 00:04:12,668 --> 00:04:15,334 To maintain the turbines, 83 00:04:15,334 --> 00:04:16,134 The electricity 84 00:04:16,134 --> 00:04:20,100 Doesn't get produced. 85 00:04:20,100 --> 00:04:22,501 as generating plants go down, 86 00:04:22,501 --> 00:04:24,034 Outages on the power grid 87 00:04:24,034 --> 00:04:25,401 Contribute to a cascade 88 00:04:25,401 --> 00:04:29,867 Of failure worldwide. 89 00:04:29,867 --> 00:04:31,434 After a few weeks, 90 00:04:31,434 --> 00:04:32,501 The planet is plunged 91 00:04:32,501 --> 00:04:33,967 Into a deep darkness. 92 00:04:33,967 --> 00:04:35,334 It has not experienced 93 00:04:35,334 --> 00:04:37,267 Since humans first huddled 94 00:04:37,267 --> 00:04:41,334 Around campfires. 95 00:04:41,334 --> 00:04:42,767 Perhaps, the last glow 96 00:04:42,767 --> 00:04:45,134 Of artificial lights on earth 97 00:04:45,134 --> 00:04:45,934 Will be seen 98 00:04:45,934 --> 00:04:52,467 In the American southwest. 99 00:04:52,467 --> 00:04:54,301 Here, the mighty hover dam 100 00:04:54,301 --> 00:04:55,800 Hydropower plant 101 00:04:55,800 --> 00:04:56,800 Takes little notice 102 00:04:56,800 --> 00:05:00,800 Of the absence of humans. 103 00:05:00,800 --> 00:05:01,867 Its source of fuel 104 00:05:01,867 --> 00:05:03,833 Is virtually limitless. 105 00:05:03,900 --> 00:05:05,234 at hover dam, 106 00:05:05,234 --> 00:05:06,401 Our fuel supply 107 00:05:06,401 --> 00:05:07,867 Is actually the water 108 00:05:07,867 --> 00:05:09,800 In the reservoir in Lake Mead 109 00:05:09,800 --> 00:05:13,767 Behind hover dam, 110 00:05:13,900 --> 00:05:15,167 So as long as there's water 111 00:05:15,167 --> 00:05:16,234 In the reservoir, 112 00:05:16,234 --> 00:05:17,167 This power plant 113 00:05:17,167 --> 00:05:22,334 Can keep running. 114 00:05:22,334 --> 00:05:23,568 There's water in the reservoir 115 00:05:23,568 --> 00:05:24,934 Keeps supplying the water 116 00:05:24,934 --> 00:05:30,134 To the hydro turbine generators. 117 00:05:30,134 --> 00:05:31,000 These generators 118 00:05:31,000 --> 00:05:33,234 Are operating automatically 119 00:05:33,234 --> 00:05:34,467 And that would continue 120 00:05:34,467 --> 00:05:36,100 As long as all of the systems 121 00:05:36,100 --> 00:05:40,234 Are functioning normally. 122 00:05:40,234 --> 00:05:43,000 If I and my staff 123 00:05:43,000 --> 00:05:44,401 Were to leave tonight 124 00:05:44,401 --> 00:05:48,401 And not come back to hover dam, 125 00:05:48,401 --> 00:05:49,568 Say just in the condition 126 00:05:49,568 --> 00:05:51,601 Of the plant is in right now, 127 00:05:51,601 --> 00:05:52,767 This would continue operating 128 00:05:52,767 --> 00:05:55,568 Without us here. 129 00:05:55,568 --> 00:05:56,434 That would still be true 130 00:05:56,434 --> 00:06:00,034 After about a week, 131 00:06:00,034 --> 00:06:04,267 Several weeks, several months, 132 00:06:04,267 --> 00:06:05,334 Maybe even a couple of years, 133 00:06:05,334 --> 00:06:06,301 Everything would still be 134 00:06:06,301 --> 00:06:10,167 Running normally. 135 00:06:10,167 --> 00:06:11,534 In a life after people, 136 00:06:11,534 --> 00:06:13,301 It is possible that hover dam 137 00:06:13,301 --> 00:06:13,867 Would be one 138 00:06:13,867 --> 00:06:14,800 Of the last power plants 139 00:06:14,800 --> 00:06:21,267 Still running. 140 00:06:21,267 --> 00:06:22,401 as the power goes out 141 00:06:22,401 --> 00:06:24,634 Around the world, 142 00:06:24,634 --> 00:06:25,800 Other systems 143 00:06:25,800 --> 00:06:30,534 Are quickly beginning to fail. 144 00:06:30,534 --> 00:06:32,234 beneath all the major cities, 145 00:06:32,234 --> 00:06:33,434 There's a complex network 146 00:06:33,434 --> 00:06:35,967 Of underground tunnels, 147 00:06:35,967 --> 00:06:36,501 And these are there 148 00:06:36,501 --> 00:06:38,234 For drainage purposes 149 00:06:38,234 --> 00:06:39,568 Or for cabling purposes, 150 00:06:39,568 --> 00:06:40,201 And in the case 151 00:06:40,201 --> 00:06:41,234 Of the big cities, 152 00:06:41,234 --> 00:06:48,167 For transportation as well. 153 00:06:48,167 --> 00:06:49,134 There are many of those 154 00:06:49,134 --> 00:06:50,501 Sit below the level 155 00:06:50,501 --> 00:06:52,900 Of the water table, 156 00:06:52,900 --> 00:06:54,934 And in order to keep them dry, 157 00:06:54,934 --> 00:06:55,733 We have to have 158 00:06:55,733 --> 00:06:56,900 A system of pumps 159 00:06:56,900 --> 00:06:57,534 That is switched on 160 00:06:57,534 --> 00:06:58,668 When necessary 161 00:06:58,668 --> 00:07:03,067 To drain the tunnels. 162 00:07:03,067 --> 00:07:04,167 deep within new York 163 00:07:04,167 --> 00:07:05,568 City subways, 164 00:07:05,568 --> 00:07:06,867 More than 700 pumps 165 00:07:06,867 --> 00:07:08,767 Constantly struggle to keep out 166 00:07:08,767 --> 00:07:11,367 A flood of ground water, 167 00:07:11,367 --> 00:07:13,234 An average of 13 million gallons 168 00:07:13,234 --> 00:07:17,267 A day. 169 00:07:17,267 --> 00:07:18,334 now, if all these people 170 00:07:18,334 --> 00:07:19,568 Were not around, 171 00:07:19,568 --> 00:07:20,568 There will be nobody 172 00:07:20,568 --> 00:07:22,568 To switch the pumps on. 173 00:07:22,568 --> 00:07:23,267 It's estimated, 174 00:07:23,267 --> 00:07:24,568 That the tunnels will fill 175 00:07:24,568 --> 00:07:28,034 With water in about 36 hours. 176 00:07:28,034 --> 00:07:42,434 [music] 177 00:07:42,434 --> 00:07:44,100 back above ground, 178 00:07:44,100 --> 00:07:44,967 Food is rotting 179 00:07:44,967 --> 00:07:57,601 On supermarket shelves. 180 00:07:57,601 --> 00:07:58,434 Home refrigerators 181 00:07:58,434 --> 00:07:59,401 Become nothing more 182 00:07:59,401 --> 00:08:02,900 Than cabinets for decaying food, 183 00:08:02,900 --> 00:08:03,900 But melt water 184 00:08:03,900 --> 00:08:05,733 From defrosting freezers 185 00:08:05,733 --> 00:08:07,800 May provide a temporary lifeline 186 00:08:07,800 --> 00:08:09,201 For some of the creatures 187 00:08:09,201 --> 00:08:13,034 We've left behind. 188 00:08:13,034 --> 00:08:14,034 What will be the fate? 189 00:08:14,034 --> 00:08:15,434 Of our family pets 190 00:08:15,434 --> 00:08:17,034 Once there are no humans left 191 00:08:17,034 --> 00:08:18,668 To care for them? 192 00:08:18,668 --> 00:08:20,434 right from the get-go, 193 00:08:20,434 --> 00:08:22,367 There's going to be a massive 194 00:08:22,367 --> 00:08:25,334 Die off of dogs. 195 00:08:25,401 --> 00:08:26,700 The instance that humans 196 00:08:26,700 --> 00:08:27,100 Are gone, 197 00:08:27,100 --> 00:08:30,568 They're not creating the debris 198 00:08:30,568 --> 00:08:32,668 Or producing the food 199 00:08:32,668 --> 00:08:41,100 That the dogs are living on. 200 00:08:41,234 --> 00:08:42,367 He can't open cans, 201 00:08:42,367 --> 00:08:42,934 He can't get 202 00:08:42,934 --> 00:08:45,867 In the refrigerator. 203 00:08:45,867 --> 00:08:46,401 They got to get 204 00:08:46,401 --> 00:08:49,568 Out of the house. 205 00:08:49,568 --> 00:08:50,367 The family dog 206 00:08:50,367 --> 00:08:53,234 Has got to get out of the house 207 00:08:53,234 --> 00:08:57,401 Or he's going to die there. 208 00:08:57,401 --> 00:08:58,668 And once he gets out, 209 00:08:58,668 --> 00:08:59,367 He's got to go 210 00:08:59,367 --> 00:09:08,301 To some source of food. 211 00:09:08,301 --> 00:09:09,134 The first thing that happens 212 00:09:09,134 --> 00:09:10,267 Is that they all jump out 213 00:09:10,267 --> 00:09:11,034 Of the windows 214 00:09:11,034 --> 00:09:12,501 And they are now out there 215 00:09:12,501 --> 00:09:14,067 In a new landscape. 216 00:09:14,067 --> 00:09:15,867 And the first to whack at it 217 00:09:15,867 --> 00:09:18,201 It is that they go back 218 00:09:18,201 --> 00:09:20,034 To scavenging a whole bunch 219 00:09:20,034 --> 00:09:20,967 Of dead things out there 220 00:09:20,967 --> 00:09:25,234 In the world. 221 00:09:25,234 --> 00:09:26,568 there are estimated to be 222 00:09:26,568 --> 00:09:28,067 Four hundred million dogs 223 00:09:28,067 --> 00:09:31,467 In the world 224 00:09:31,467 --> 00:09:37,601 And 300 different breeds. 225 00:09:37,601 --> 00:09:39,301 But very few of them are suited 226 00:09:39,301 --> 00:09:40,733 To surviving in a life 227 00:09:40,733 --> 00:09:46,067 After humans. 228 00:09:46,067 --> 00:09:46,800 The smallest dogs 229 00:09:46,800 --> 00:09:48,367 Probably won't last a week 230 00:09:48,367 --> 00:09:50,134 Without us. 231 00:09:50,134 --> 00:09:51,100 there's probably no niche 232 00:09:51,100 --> 00:09:53,833 For the smaller dogs. 233 00:09:53,900 --> 00:09:55,000 Dogs are very competitive 234 00:09:55,000 --> 00:09:56,334 And when you have wolves, 235 00:09:56,334 --> 00:09:57,401 They displace coyotes, 236 00:09:57,401 --> 00:09:58,467 Coyotes displace foxes, 237 00:09:58,467 --> 00:09:59,668 And we would assume 238 00:09:59,800 --> 00:10:02,234 That hierarchy would prevail 239 00:10:02,234 --> 00:10:05,234 Among domestic dogs. 240 00:10:05,234 --> 00:10:05,934 in fact, 241 00:10:05,934 --> 00:10:07,501 Many of the unique features 242 00:10:07,501 --> 00:10:09,267 That has been bred into dogs 243 00:10:09,267 --> 00:10:10,700 Over the years 244 00:10:10,700 --> 00:10:12,700 Will now become major handicaps 245 00:10:12,700 --> 00:10:14,800 In the fight for survival. 246 00:10:14,800 --> 00:10:15,733 there are dog 247 00:10:15,733 --> 00:10:17,067 For the really short legs, 248 00:10:17,067 --> 00:10:17,967 I think the dogs 249 00:10:17,967 --> 00:10:19,833 With the really short faces 250 00:10:19,833 --> 00:10:22,201 Or long faces, I think, 251 00:10:22,201 --> 00:10:25,301 That they're all doomed. 252 00:10:25,301 --> 00:10:25,867 You know, they're not 253 00:10:25,867 --> 00:10:26,900 Going to move well, 254 00:10:26,900 --> 00:10:27,634 They're not going to be able 255 00:10:27,634 --> 00:10:32,668 To search and explore. 256 00:10:32,668 --> 00:10:33,367 I think that the kind of 257 00:10:33,367 --> 00:10:35,401 The middle of the spectrum, 258 00:10:35,401 --> 00:10:38,201 The kind of average dog, 259 00:10:38,201 --> 00:10:42,000 Have the best chances in this. 260 00:10:42,000 --> 00:10:44,733 I think that they will survive 261 00:10:44,733 --> 00:10:46,434 In the long haul, 262 00:10:46,434 --> 00:10:49,767 But it's not going to be pretty. 263 00:10:49,767 --> 00:10:51,301 as the surviving dogs 264 00:10:51,301 --> 00:10:52,234 Struggle to find 265 00:10:52,234 --> 00:10:53,867 Their new niche, 266 00:10:53,867 --> 00:10:54,833 Household pests 267 00:10:54,833 --> 00:10:56,568 Are slowly beginning to notice 268 00:10:56,568 --> 00:11:02,934 Our absence. 269 00:11:03,900 --> 00:11:04,800 Little creatures, 270 00:11:04,800 --> 00:11:06,434 Rats and house mice, 271 00:11:06,434 --> 00:11:07,467 They would seem to be able 272 00:11:07,467 --> 00:11:09,034 To exist without us 273 00:11:09,034 --> 00:11:10,767 Are surprisingly quite dependent 274 00:11:10,767 --> 00:11:13,401 On our food supplies. 275 00:11:13,401 --> 00:11:14,601 rats and mice 276 00:11:14,601 --> 00:11:16,401 Are usually termed 277 00:11:16,401 --> 00:11:18,067 "commensally rodents," which means 278 00:11:18,067 --> 00:11:19,568 That term means literally 279 00:11:19,568 --> 00:11:20,967 Sharing the table. 280 00:11:20,967 --> 00:11:21,900 They're very dependent 281 00:11:21,900 --> 00:11:23,201 On people. 282 00:11:23,201 --> 00:11:24,900 And the little house mouse 283 00:11:24,900 --> 00:11:26,301 And Norway rat 284 00:11:26,301 --> 00:11:28,900 Are great examples of animals? 285 00:11:28,900 --> 00:11:30,467 That would do less well 286 00:11:30,467 --> 00:11:35,634 In the absence of people. 287 00:11:35,634 --> 00:11:36,700 in the initial weeks 288 00:11:36,700 --> 00:11:38,034 After people are gone, 289 00:11:38,034 --> 00:11:39,401 They will raid pantries 290 00:11:39,401 --> 00:11:42,167 In homes, in grocery shelves 291 00:11:42,167 --> 00:11:50,134 In stores. 292 00:11:50,134 --> 00:11:50,934 After eating through 293 00:11:50,934 --> 00:11:51,800 These food supplies, 294 00:11:51,800 --> 00:11:53,668 They will struggle to survive 295 00:11:53,668 --> 00:11:55,800 On things like cardboard, cloth, 296 00:11:55,800 --> 00:11:59,000 Or glue. 297 00:11:59,000 --> 00:12:00,668 I think that if a city 298 00:12:00,668 --> 00:12:01,634 Was abandoned, 299 00:12:01,634 --> 00:12:02,668 The rats would have to go back 300 00:12:02,668 --> 00:12:05,201 To earning an honest living. 301 00:12:05,201 --> 00:12:06,100 An honest living 302 00:12:06,100 --> 00:12:09,634 Means to go back to the wild 303 00:12:09,634 --> 00:12:13,234 And compete for resources there. 304 00:12:13,234 --> 00:12:14,367 eventually, these rodents 305 00:12:14,367 --> 00:12:15,568 Will abandon homes 306 00:12:15,568 --> 00:12:18,733 And buildings, 307 00:12:18,733 --> 00:12:19,568 Which will make them? 308 00:12:19,568 --> 00:12:25,201 Easy pickings for predators. 309 00:12:25,201 --> 00:12:26,067 Although, rats and mice 310 00:12:26,067 --> 00:12:27,167 Will mostly likely survive 311 00:12:27,167 --> 00:12:28,301 In the future, 312 00:12:28,301 --> 00:12:28,967 Their numbers 313 00:12:28,967 --> 00:12:37,568 Will be greatly diminished. 314 00:12:37,568 --> 00:12:38,733 After six months 315 00:12:38,733 --> 00:12:42,434 Into a life after people, 316 00:12:42,434 --> 00:12:42,900 Urban areas 317 00:12:42,900 --> 00:12:44,967 Are already taking a turn 318 00:12:44,967 --> 00:12:47,334 For the wild. 319 00:12:47,334 --> 00:12:48,800 the predators would return 320 00:12:48,800 --> 00:12:49,967 Very quickly in the absence 321 00:12:49,967 --> 00:12:52,401 Of humans 322 00:12:52,401 --> 00:12:53,800 Because we suppress them, 323 00:12:53,800 --> 00:12:55,167 We create conditions 324 00:12:55,167 --> 00:12:56,934 That either work against them, 325 00:12:56,934 --> 00:12:58,467 Or we deliberately go out, 326 00:12:58,467 --> 00:13:00,833 And remove and destroy them. 327 00:13:00,833 --> 00:13:01,700 They would come back 328 00:13:01,700 --> 00:13:04,668 Very quickly. 329 00:13:04,668 --> 00:13:05,534 smaller predators 330 00:13:05,534 --> 00:13:07,201 Like coyotes and bobcats 331 00:13:07,201 --> 00:13:08,601 Always survive on the fringe 332 00:13:08,601 --> 00:13:11,000 Of human populations. 333 00:13:11,000 --> 00:13:12,668 They are the first to colonize 334 00:13:12,668 --> 00:13:17,267 Our abandoned neighborhoods. 335 00:13:17,267 --> 00:13:18,067 Larger carnivores 336 00:13:18,067 --> 00:13:19,401 Will have to wait longer 337 00:13:19,401 --> 00:13:20,167 For the habitat 338 00:13:20,167 --> 00:13:21,034 To recover enough 339 00:13:21,034 --> 00:13:23,800 To support their appetites. 340 00:13:23,800 --> 00:13:25,700 But soon enough, they, too, 341 00:13:25,700 --> 00:13:26,800 Will hunt in what 342 00:13:26,800 --> 00:13:31,833 Were once our backyards. 343 00:13:31,833 --> 00:13:40,167 ] 344 00:13:40,167 --> 00:13:41,800 One year into a life 345 00:13:41,800 --> 00:13:43,301 After people, 346 00:13:43,301 --> 00:13:44,301 Towns and cities 347 00:13:44,301 --> 00:13:46,601 Are still recognizable. 348 00:13:46,601 --> 00:13:47,167 But nature 349 00:13:47,167 --> 00:13:48,900 Is beginning to reclaim 350 00:13:48,900 --> 00:13:52,967 Her old turf. 351 00:13:52,967 --> 00:13:53,700 one of the first 352 00:13:53,700 --> 00:13:55,000 Great physical effects 353 00:13:55,000 --> 00:13:56,634 In the absence of people 354 00:13:56,700 --> 00:13:58,668 Would be the transition 355 00:13:58,668 --> 00:14:00,634 Of the impervious surfaces: 356 00:14:00,634 --> 00:14:01,467 The parking lots, the roads 357 00:14:01,467 --> 00:14:04,668 Into places that supported 358 00:14:04,668 --> 00:14:06,301 And then had an abundance 359 00:14:06,301 --> 00:14:09,334 Of plant life. 360 00:14:09,467 --> 00:14:09,833 any place 361 00:14:09,833 --> 00:14:11,100 Where you have sunlight 362 00:14:11,100 --> 00:14:13,668 That's hitting, 363 00:14:13,668 --> 00:14:14,301 You're probably going to get 364 00:14:14,301 --> 00:14:16,000 Some plant growth. 365 00:14:16,067 --> 00:14:16,534 Little seeds 366 00:14:16,534 --> 00:14:17,201 Are going to get stuck 367 00:14:17,201 --> 00:14:18,833 In the cracks and so forth, 368 00:14:18,833 --> 00:14:19,301 And these things 369 00:14:19,301 --> 00:14:23,334 Are all going to start to creep? 370 00:14:23,467 --> 00:14:25,668 Plants are wonderful that way. 371 00:14:25,668 --> 00:14:27,301 They can destroy things 372 00:14:27,301 --> 00:14:29,601 In matters of, you know, 373 00:14:29,601 --> 00:14:37,568 A few years. 374 00:14:37,568 --> 00:14:38,201 without humans 375 00:14:38,201 --> 00:14:39,833 To remove them, 376 00:14:39,833 --> 00:14:41,534 Weeds like dandelions 377 00:14:41,534 --> 00:14:43,034 Infiltrate every crack 378 00:14:43,034 --> 00:14:46,401 In the pavement. 379 00:14:46,401 --> 00:14:47,867 As these weeds die, 380 00:14:47,867 --> 00:14:49,067 Their remnants combine 381 00:14:49,067 --> 00:14:50,601 With ever-spreading moss 382 00:14:50,601 --> 00:14:52,167 And lichen 383 00:14:52,167 --> 00:14:58,668 To create a layer of topsoil. 384 00:14:58,668 --> 00:14:59,733 This sandy soil 385 00:14:59,733 --> 00:15:02,501 Is poor in nutrients, 386 00:15:02,501 --> 00:15:04,668 So only plants like clover 387 00:15:04,668 --> 00:15:05,733 That can pull nitrogen 388 00:15:05,733 --> 00:15:07,234 From the air 389 00:15:07,234 --> 00:15:11,301 Flourish at first. 390 00:15:11,301 --> 00:15:13,167 Formerly manicured yards 391 00:15:13,167 --> 00:15:16,534 Morph into fields 392 00:15:16,534 --> 00:15:17,967 For a white-tailed deer 393 00:15:17,967 --> 00:15:22,234 Forage for food. 394 00:15:22,234 --> 00:15:24,034 Wild animals have also begun 395 00:15:24,034 --> 00:15:24,967 To find their way 396 00:15:24,967 --> 00:15:33,833 Into abandoned cities. 397 00:15:33,833 --> 00:15:35,700 Man's supposed domination 398 00:15:35,700 --> 00:15:36,833 Over nature 399 00:15:36,833 --> 00:15:40,034 Has proven to be quite tenuous. 400 00:15:40,034 --> 00:15:41,934 The signs of our vulnerability 401 00:15:41,934 --> 00:15:45,867 Have always been there. 402 00:15:45,934 --> 00:15:48,201 this is an ailanthus tree. 403 00:15:48,201 --> 00:15:50,334 It seems to enjoy rooting itself 404 00:15:50,334 --> 00:15:52,934 In very inhospitable locations. 405 00:15:52,934 --> 00:15:54,267 And it likes to attach itself 406 00:15:54,267 --> 00:15:55,934 To crevices in buildings. 407 00:15:56,067 --> 00:15:57,067 And when it does so, 408 00:15:57,067 --> 00:15:58,401 It causes damage. 409 00:15:58,401 --> 00:15:59,668 The roots expand, 410 00:15:59,668 --> 00:16:02,301 And the expansive forces of that 411 00:16:02,301 --> 00:16:03,767 Force out mortar 412 00:16:03,767 --> 00:16:05,568 And stone and cause crumbling 413 00:16:05,568 --> 00:16:06,568 Of a facade. 414 00:16:06,568 --> 00:16:07,668 If you get a lot of this 415 00:16:07,668 --> 00:16:09,167 On an entire building facade, 416 00:16:09,167 --> 00:16:10,334 It could cause 417 00:16:10,334 --> 00:16:17,700 Major, major damage. 418 00:16:17,700 --> 00:16:20,000 as nature battles back, 419 00:16:20,000 --> 00:16:21,733 Even manmade goliaths 420 00:16:21,733 --> 00:16:22,967 Like hover dam 421 00:16:22,967 --> 00:16:26,401 Aren't invincible. 422 00:16:26,401 --> 00:16:27,234 To harness the power 423 00:16:27,234 --> 00:16:28,434 Of this river 424 00:16:28,434 --> 00:16:31,434 Took 21,000 men and five years 425 00:16:31,434 --> 00:16:36,067 Of hard labor. 426 00:16:36,067 --> 00:16:38,000 But one year after people, 427 00:16:38,000 --> 00:16:40,634 Its 17 massive and seemingly 428 00:16:40,634 --> 00:16:42,833 Indestructible generators 429 00:16:42,833 --> 00:16:43,833 Are about to be brought down 430 00:16:43,833 --> 00:16:45,401 By an organism 431 00:16:45,401 --> 00:16:52,800 The size of a human thumbnail. 432 00:16:52,800 --> 00:16:54,067 The lake above the dam 433 00:16:54,067 --> 00:16:55,000 Is infested 434 00:16:55,000 --> 00:16:56,267 With an invasive species 435 00:16:56,267 --> 00:16:57,167 Of mollusk 436 00:16:57,167 --> 00:17:00,900 Called the "quake mussel." 437 00:17:00,900 --> 00:17:02,134 This stealthy invader 438 00:17:02,134 --> 00:17:03,100 From Eastern Europe 439 00:17:03,100 --> 00:17:04,733 Had no natural predators 440 00:17:04,733 --> 00:17:06,401 In North America 441 00:17:06,401 --> 00:17:07,934 Other than the humans tasked 442 00:17:07,934 --> 00:17:09,534 With scraping it from the grates 443 00:17:09,534 --> 00:17:12,467 And pipes it colonizes. 444 00:17:12,534 --> 00:17:14,067 the mussels attach themselves 445 00:17:14,067 --> 00:17:18,301 To the inside wall of pipes 446 00:17:18,301 --> 00:17:19,867 And they're very prolific. 447 00:17:19,867 --> 00:17:20,800 They colonize 448 00:17:20,800 --> 00:17:22,167 And rapidly build up 449 00:17:22,167 --> 00:17:23,267 And can grow 450 00:17:23,267 --> 00:17:25,833 On top of each other, 451 00:17:25,967 --> 00:17:28,534 And eventually completely block 452 00:17:28,534 --> 00:17:40,134 The diameter of a pipe. 453 00:17:40,134 --> 00:17:41,000 the small pipes 454 00:17:41,000 --> 00:17:42,334 That brings cooling water 455 00:17:42,334 --> 00:17:44,301 To hover dam's generators 456 00:17:44,301 --> 00:17:45,234 Make perfect homes 457 00:17:45,234 --> 00:17:47,167 For these creatures. 458 00:17:47,167 --> 00:17:48,301 And with no people around 459 00:17:48,301 --> 00:17:49,733 To remove them, 460 00:17:49,733 --> 00:17:52,867 They spread like a cancer. 461 00:17:52,867 --> 00:17:53,467 and in fact, 462 00:17:53,467 --> 00:17:55,434 Those mussels could clog up 463 00:17:55,434 --> 00:17:57,967 The cooling water pipes, 464 00:17:57,967 --> 00:17:58,367 To the point 465 00:17:58,367 --> 00:18:00,000 Where we couldn't keep 466 00:18:00,000 --> 00:18:09,833 These generators cool anymore. 467 00:18:09,833 --> 00:18:11,000 And it would cause 468 00:18:11,000 --> 00:18:12,401 The high temperature alarm 469 00:18:12,401 --> 00:18:15,601 In the automatic control system. 470 00:18:15,601 --> 00:18:16,568 And that automatic 471 00:18:16,568 --> 00:18:17,501 Control system 472 00:18:17,501 --> 00:18:18,467 Would then start 473 00:18:18,467 --> 00:18:19,934 The shutdown sequence 474 00:18:19,934 --> 00:18:23,000 Of that generator. 475 00:18:23,000 --> 00:18:24,000 Well, that would happen 476 00:18:24,000 --> 00:18:24,833 One by one 477 00:18:24,833 --> 00:18:25,934 For all of the generators 478 00:18:25,934 --> 00:18:26,700 Of hover dam, 479 00:18:26,700 --> 00:18:27,234 And eventually 480 00:18:27,234 --> 00:18:28,201 The entire power plant 481 00:18:28,201 --> 00:18:31,601 Would be shut down. 482 00:18:31,601 --> 00:18:33,000 in lass Vegas, 483 00:18:33,000 --> 00:18:33,967 The last glimmers 484 00:18:33,967 --> 00:18:36,301 Of manmade light on earth 485 00:18:36,301 --> 00:18:37,634 Relinquish the night 486 00:18:37,634 --> 00:18:41,501 To its primeval blackness. 487 00:18:41,501 --> 00:18:42,167 With the generators 488 00:18:42,167 --> 00:18:43,900 No longer running, 489 00:18:43,900 --> 00:18:44,833 No water at all 490 00:18:44,833 --> 00:18:51,000 Is passing through hover dam. 491 00:18:51,000 --> 00:18:52,067 And the Colorado River 492 00:18:52,067 --> 00:18:58,401 Downstream begins to run dry. 493 00:18:58,401 --> 00:19:00,367 On the other side of the dam, 494 00:19:00,367 --> 00:19:02,967 The water has nowhere to go 495 00:19:02,967 --> 00:19:06,568 And Lake Mead starts to rise. 496 00:19:06,568 --> 00:19:07,134 it would just keep 497 00:19:07,134 --> 00:19:10,034 Building up in Lake Mead. 498 00:19:10,034 --> 00:19:10,733 And it would eventually 499 00:19:10,733 --> 00:19:11,301 Gets to the point 500 00:19:11,301 --> 00:19:12,634 Of spilling over 501 00:19:12,634 --> 00:19:13,501 Through the spillways 502 00:19:13,501 --> 00:19:18,900 On either side of the dam. 503 00:19:18,900 --> 00:19:20,067 unchecked, 504 00:19:20,067 --> 00:19:22,067 Nature's most powerful elements 505 00:19:22,067 --> 00:19:23,601 Reclaim their supremacy 506 00:19:23,601 --> 00:19:27,800 On earth. 507 00:19:27,800 --> 00:19:30,000 Triggered by lightning strikes, 508 00:19:30,000 --> 00:19:30,668 The wildfires 509 00:19:30,668 --> 00:19:32,201 Those humans once battled 510 00:19:32,201 --> 00:19:33,501 So valiantly 511 00:19:33,501 --> 00:19:43,134 Now rage unchecked. 512 00:19:43,134 --> 00:19:44,301 Cities and neighborhoods 513 00:19:44,301 --> 00:19:46,034 Full of abandoned buildings, 514 00:19:46,034 --> 00:19:48,267 Wild grasses, and debris 515 00:19:48,267 --> 00:19:59,234 Is prime fuel for the flames? 516 00:19:59,234 --> 00:20:04,568 Chicago burns. 517 00:20:04,568 --> 00:20:05,434 San's 518 00:20:05,434 --> 00:20:07,900 Stately wooden Victorians 519 00:20:07,900 --> 00:20:14,568 Are now only useful as kindling. 520 00:20:14,568 --> 00:20:15,568 And just as it did 521 00:20:15,568 --> 00:20:17,501 In the time of the ancients, 522 00:20:17,501 --> 00:20:23,668 Rome is burning again. 523 00:20:23,668 --> 00:20:24,467 As structures 524 00:20:24,467 --> 00:20:26,167 Burn to the ground, 525 00:20:26,167 --> 00:20:26,967 Charred timbers 526 00:20:26,967 --> 00:20:29,201 Release nutrients into the soil, 527 00:20:29,201 --> 00:20:30,267 Providing the next wave 528 00:20:30,267 --> 00:20:31,601 Of plant life, 529 00:20:31,601 --> 00:20:32,167 With the nitrogen 530 00:20:32,167 --> 00:20:35,100 It needs to grow 531 00:20:35,100 --> 00:20:50,267 And thrive. 532 00:20:50,267 --> 00:20:52,434 Five years after people, 533 00:20:52,434 --> 00:20:53,467 The roads of the world 534 00:20:53,467 --> 00:20:54,401 Are disappearing 535 00:20:54,401 --> 00:20:55,934 Beneath a green map 536 00:20:55,934 --> 00:20:56,534 That spreads 537 00:20:56,534 --> 00:21:01,800 Like some relentless monster. 538 00:21:01,800 --> 00:21:02,934 The advance of nature 539 00:21:02,934 --> 00:21:05,800 Knows no boundaries. 540 00:21:05,800 --> 00:21:06,234 The gates 541 00:21:06,234 --> 00:21:08,100 Of London's Buckingham palace 542 00:21:08,100 --> 00:21:09,800 Are easily breached by vines 543 00:21:09,800 --> 00:21:12,401 And moss. 544 00:21:12,401 --> 00:21:14,367 In Moscow, red square 545 00:21:14,367 --> 00:21:17,534 Is becoming very green. 546 00:21:17,601 --> 00:21:18,034 in reality, 547 00:21:18,034 --> 00:21:19,334 Nature will reclaim earth 548 00:21:19,334 --> 00:21:21,934 Very quickly. 549 00:21:22,067 --> 00:21:22,967 These stairs were cleared 550 00:21:22,967 --> 00:21:25,201 18 months ago. 551 00:21:25,201 --> 00:21:25,668 If we came back 552 00:21:25,668 --> 00:21:26,833 In another 18 months, 553 00:21:26,833 --> 00:21:27,634 We'd have a hard time 554 00:21:27,634 --> 00:21:29,967 Finding them. 555 00:21:29,967 --> 00:21:31,201 If we came back in five years, 556 00:21:31,201 --> 00:21:32,367 It would be almost impossible 557 00:21:32,367 --> 00:21:34,634 To find. 558 00:21:34,634 --> 00:21:36,501 man's mastery over nature 559 00:21:36,501 --> 00:21:37,167 Has always been 560 00:21:37,167 --> 00:21:42,034 Just an illusion. 561 00:21:42,034 --> 00:21:43,201 When the Cambodian city 562 00:21:43,201 --> 00:21:44,100 Of Angkor 563 00:21:44,100 --> 00:21:45,668 And its temple complexes 564 00:21:45,668 --> 00:21:48,401 Were abandoned in 15th century, 565 00:21:48,401 --> 00:21:49,467 Jungle trees grew 566 00:21:49,467 --> 00:21:50,833 Indiscriminately 567 00:21:50,833 --> 00:21:52,601 Over its stone structures. 568 00:21:52,601 --> 00:22:00,833 Entangling them in their roots. 569 00:22:00,833 --> 00:22:03,067 Now, without armies of gardeners 570 00:22:03,067 --> 00:22:04,534 And repairmen, 571 00:22:04,534 --> 00:22:06,301 Modern cities are laid bare 572 00:22:06,301 --> 00:22:10,867 To nature's revenge. 573 00:22:10,867 --> 00:22:12,700 In New York's central park, 574 00:22:12,700 --> 00:22:14,700 The great lawns, now untended, 575 00:22:14,700 --> 00:22:18,800 Sprout with saplings. 576 00:22:18,800 --> 00:22:20,733 Five years without humans 577 00:22:20,733 --> 00:22:21,401 Leaves the park 578 00:22:21,401 --> 00:22:25,134 Looking more like a forest. 579 00:22:25,134 --> 00:22:29,134 central park will go bananas. 580 00:22:29,134 --> 00:22:30,201 So all of a sudden 581 00:22:30,201 --> 00:22:30,967 You'll get trees, 582 00:22:30,967 --> 00:22:33,934 You'll get growth. 583 00:22:33,934 --> 00:22:35,668 All the animals and plants 584 00:22:35,668 --> 00:22:38,000 That is there now will go up 585 00:22:38,000 --> 00:22:39,367 In population levels 586 00:22:39,367 --> 00:22:40,668 And they'll start to spread out 587 00:22:40,668 --> 00:22:45,767 Into the city. 588 00:22:45,767 --> 00:22:46,800 the story is the same 589 00:22:46,800 --> 00:22:50,367 In Washington o.k. 590 00:22:50,367 --> 00:22:51,134 The great monuments 591 00:22:51,134 --> 00:22:57,434 Have been swallowed by greenery. 592 00:22:57,434 --> 00:22:58,334 And on what used to be 593 00:22:58,334 --> 00:23:01,301 The national mall, 594 00:23:01,301 --> 00:23:02,568 The sounds of the jungle 595 00:23:02,568 --> 00:23:04,201 Are echoing. 596 00:23:04,201 --> 00:23:04,833 zoo animals 597 00:23:04,833 --> 00:23:10,134 Are really the great unknown. 598 00:23:10,134 --> 00:23:11,201 Depending on whether or not 599 00:23:11,201 --> 00:23:12,634 They could escape 600 00:23:12,634 --> 00:23:13,601 From their confinement, 601 00:23:13,601 --> 00:23:15,967 Then things change dramatically 602 00:23:15,967 --> 00:23:17,501 Because you might have lions, 603 00:23:17,501 --> 00:23:18,900 You might have tigers; 604 00:23:18,900 --> 00:23:19,601 Both of which 605 00:23:19,601 --> 00:23:21,000 Would be perfectly capable 606 00:23:21,000 --> 00:23:22,067 Of surviving 607 00:23:22,067 --> 00:23:27,967 In a post-human period. 608 00:23:27,967 --> 00:23:29,568 They'd do better further south 609 00:23:29,568 --> 00:23:30,100 Than they would do 610 00:23:30,100 --> 00:23:32,000 in Washington o.k. 611 00:23:32,000 --> 00:23:33,467 But these are animals 612 00:23:33,467 --> 00:23:34,668 That is perfectly capable 613 00:23:34,668 --> 00:23:36,100 Of figuring out how to do it 614 00:23:36,100 --> 00:23:38,501 And how to survive. 615 00:23:38,501 --> 00:23:39,201 zoo animals 616 00:23:39,201 --> 00:23:41,234 May be the great unknown 617 00:23:41,234 --> 00:23:41,867 But there are things 618 00:23:41,867 --> 00:23:43,267 We can know for sure 619 00:23:43,267 --> 00:23:44,867 About life 20 years 620 00:23:44,867 --> 00:23:50,601 After people are gone 621 00:23:50,601 --> 00:23:51,934 Because there's one spot 622 00:23:51,934 --> 00:23:53,601 On the globe 623 00:23:53,601 --> 00:23:58,668 Where it's already happened. 624 00:23:58,668 --> 00:24:18,900 [music] 625 00:24:19,800 --> 00:24:20,667 it's 20 years 626 00:24:20,667 --> 00:24:26,434 Into a life after people. 627 00:24:26,434 --> 00:24:27,000 Without humans 628 00:24:27,000 --> 00:24:28,733 To apply fresh paint 629 00:24:28,733 --> 00:24:30,534 And fill in cracks, 630 00:24:30,534 --> 00:24:31,767 Even concrete buildings 631 00:24:31,767 --> 00:24:36,401 Have already begun to crumble. 632 00:24:36,401 --> 00:24:37,967 Lack of maintenance turns cities 633 00:24:37,967 --> 00:24:45,434 Into eerie ghost towns. 634 00:24:45,434 --> 00:24:46,967 Animals that have long avoided 635 00:24:46,967 --> 00:24:48,867 Human population centers 636 00:24:48,867 --> 00:24:50,667 Now return to make new homes 637 00:24:50,667 --> 00:24:57,134 Among the decaying walls. 638 00:24:57,134 --> 00:24:59,367 How do we know this? 639 00:24:59,367 --> 00:25:00,201 Because there's one place 640 00:25:00,201 --> 00:25:01,700 In the world 641 00:25:01,700 --> 00:25:08,334 Where it's already happened. 642 00:25:08,401 --> 00:25:08,867 we're standing 643 00:25:08,867 --> 00:25:10,501 In the central square 644 00:25:10,501 --> 00:25:12,534 Of prepay, Ukraine, 645 00:25:12,534 --> 00:25:13,568 The city that was once 646 00:25:13,568 --> 00:25:15,468 The most modern city 647 00:25:15,468 --> 00:25:20,434 In the former Soviet Union. 648 00:25:22,800 --> 00:25:24,301 For 20 years now, 649 00:25:24,301 --> 00:25:25,034 This city 650 00:25:25,034 --> 00:25:26,967 Has been sitting abandoned, 651 00:25:26,967 --> 00:25:28,434 And it really gives you 652 00:25:28,434 --> 00:25:31,067 A picture of what would happen 653 00:25:31,067 --> 00:25:32,733 If people are removed 654 00:25:32,733 --> 00:25:33,534 From a place 655 00:25:33,534 --> 00:25:42,534 Of normal civilization. 656 00:25:42,534 --> 00:25:43,667 evacuated after 657 00:25:43,667 --> 00:25:46,667 The Chernobyl nuclear disaster, 658 00:25:46,667 --> 00:25:47,301 Prepay went 659 00:25:47,301 --> 00:25:52,633 From a city of 50,000 660 00:25:52,633 --> 00:26:07,367 To ghost town overnight. 661 00:26:07,367 --> 00:26:09,501 Dust-covered school rooms remain 662 00:26:09,501 --> 00:26:10,667 As students left them 663 00:26:10,667 --> 00:26:23,234 Just over 20 years ago. 664 00:26:23,234 --> 00:26:25,401 Vegetation pries apart masonry 665 00:26:25,401 --> 00:26:34,401 As it crawls over buildings. 666 00:26:34,401 --> 00:26:35,600 An amusement park 667 00:26:35,600 --> 00:26:36,600 Scheduled to open 668 00:26:36,600 --> 00:26:38,000 Four days after the date 669 00:26:38,000 --> 00:26:39,534 Of the accident 670 00:26:39,534 --> 00:26:47,267 Remains never used. 671 00:26:47,267 --> 00:26:48,600 The park's ferries wheel 672 00:26:48,600 --> 00:26:50,201 Accumulates rust 673 00:26:50,201 --> 00:27:06,568 Rather than riders. 674 00:27:06,568 --> 00:27:08,267 The bumper cars sit in a state 675 00:27:08,267 --> 00:27:16,167 Of motionless decay. 676 00:27:16,167 --> 00:27:17,934 Prepay has provided an amazing 677 00:27:17,934 --> 00:27:19,700 And rare opportunity 678 00:27:19,700 --> 00:27:20,367 To see what happens 679 00:27:20,367 --> 00:27:22,034 To a manmade city 680 00:27:22,034 --> 00:27:29,633 When humans disappear. 681 00:27:29,633 --> 00:27:30,101 I can see 682 00:27:30,101 --> 00:27:31,301 From my Geiger counter 683 00:27:31,301 --> 00:27:32,468 That it's really quite safe 684 00:27:32,468 --> 00:27:33,468 To be here, 685 00:27:33,468 --> 00:27:34,267 Radiation levels 686 00:27:34,267 --> 00:27:37,600 Were not very high. 687 00:27:37,600 --> 00:27:38,600 But you can see 688 00:27:38,600 --> 00:27:39,468 That we've really hit 689 00:27:39,468 --> 00:27:40,934 A point of no return 690 00:27:40,934 --> 00:27:48,501 In recapturing these facilities. 691 00:27:48,501 --> 00:27:49,334 We're in what was 692 00:27:49,334 --> 00:27:51,434 The cultural center 693 00:27:51,434 --> 00:27:53,501 Of the city of prepay. 694 00:27:53,501 --> 00:27:54,633 And indeed, this was a place 695 00:27:54,633 --> 00:27:56,134 Where friends gathered, 696 00:27:56,134 --> 00:27:58,301 Where there would be 697 00:27:58,301 --> 00:27:59,501 Celebrations, 698 00:27:59,501 --> 00:28:01,167 There would be balls, 699 00:28:01,167 --> 00:28:02,234 There would be music, 700 00:28:02,234 --> 00:28:03,967 There would be dancing, 701 00:28:03,967 --> 00:28:05,067 There would be performing 702 00:28:05,067 --> 00:28:10,501 On the stage here behind me. 703 00:28:10,501 --> 00:28:12,733 But after 20 years, 704 00:28:12,733 --> 00:28:14,034 The forces of nature 705 00:28:14,034 --> 00:28:14,967 Have started to decay 706 00:28:14,967 --> 00:28:18,501 This facility. 707 00:28:18,501 --> 00:28:20,301 this concrete soviet facade 708 00:28:20,301 --> 00:28:22,434 May look imposing 709 00:28:22,434 --> 00:28:23,134 But it's no match 710 00:28:23,134 --> 00:28:26,434 For the frigid Ukrainian winters. 711 00:28:26,434 --> 00:28:27,367 As the temperature drops 712 00:28:27,367 --> 00:28:28,834 Below freezing, 713 00:28:28,834 --> 00:28:30,067 Water that has accumulated 714 00:28:30,067 --> 00:28:32,267 In cracks, expands, 715 00:28:32,267 --> 00:28:33,633 Exerting bursting pressure 716 00:28:33,633 --> 00:28:35,034 That pulls apart 717 00:28:35,034 --> 00:28:37,401 The masonry. 718 00:28:37,401 --> 00:28:39,600 As vegetation grows unchecked, 719 00:28:39,600 --> 00:28:40,367 The roots spread 720 00:28:40,367 --> 00:28:43,434 Through foundations and stairs. 721 00:28:43,434 --> 00:28:45,201 These roots suck in moisture 722 00:28:45,201 --> 00:28:48,934 That makes them expand and grow. 723 00:28:48,934 --> 00:28:51,568 Like miniature hydraulic jacks, 724 00:28:51,568 --> 00:28:52,468 Over time, 725 00:28:52,468 --> 00:28:54,234 They slowly push apart 726 00:28:54,234 --> 00:29:00,101 The concrete. 727 00:29:00,101 --> 00:29:03,301 this is only 20 years. 728 00:29:03,301 --> 00:29:03,967 Can you imagine? 729 00:29:03,967 --> 00:29:04,967 What this facility 730 00:29:04,967 --> 00:29:13,434 Will look like after 200 years? 731 00:29:13,434 --> 00:29:14,700 after the accident, 732 00:29:14,700 --> 00:29:16,501 Scientists expected the worst 733 00:29:16,501 --> 00:29:19,167 For the wildlife in the region. 734 00:29:19,167 --> 00:29:19,967 Most of the trees 735 00:29:19,967 --> 00:29:22,101 In a 1 1/2 square mile area 736 00:29:22,101 --> 00:29:23,534 Around the nuclear plant 737 00:29:23,534 --> 00:29:26,434 Were killed off by radiation. 738 00:29:26,434 --> 00:29:29,867 Many animals died. 739 00:29:29,867 --> 00:29:31,900 But incredibly, the effect 740 00:29:31,900 --> 00:29:33,568 Of the absence of humans 741 00:29:33,568 --> 00:29:36,034 For 20 years has outweighed 742 00:29:36,034 --> 00:29:37,101 The initial damage 743 00:29:37,101 --> 00:29:44,434 Caused by the nuclear nightmare. 744 00:29:44,434 --> 00:29:46,101 this is the red forest, 745 00:29:46,101 --> 00:29:46,967 An area 746 00:29:46,967 --> 00:29:48,401 That was horribly impacted 747 00:29:48,401 --> 00:29:51,101 By radioactivity 748 00:29:51,101 --> 00:29:55,034 Due to the Chernobyl explosion. 749 00:29:55,034 --> 00:29:56,201 And the trees that you see 750 00:29:56,201 --> 00:29:57,867 Around me were killed 751 00:29:57,867 --> 00:30:02,000 By the radioactivity. 752 00:30:02,000 --> 00:30:03,167 The original amounts 753 00:30:03,167 --> 00:30:05,301 Of radioactivity were sufficient 754 00:30:05,301 --> 00:30:06,667 To kill all of the wildlife 755 00:30:06,667 --> 00:30:12,000 In the region as well. 756 00:30:12,000 --> 00:30:13,301 But now we see resurgence 757 00:30:13,301 --> 00:30:22,234 Of the wildlife. 758 00:30:22,234 --> 00:30:24,000 As an example of how wildlife 759 00:30:24,000 --> 00:30:26,267 Has prospered here, 760 00:30:26,267 --> 00:30:28,067 We see, here, we have an antler 761 00:30:28,067 --> 00:30:30,034 From a red deer and, obviously, 762 00:30:30,034 --> 00:30:31,067 A fairly large 763 00:30:31,067 --> 00:30:35,633 And healthy red deer. 764 00:30:35,633 --> 00:30:36,834 Red deer are hardly found 765 00:30:36,834 --> 00:30:38,568 In any other areas 766 00:30:38,568 --> 00:30:39,434 In this region 767 00:30:39,434 --> 00:30:41,334 And the Chernobyl zone 768 00:30:41,334 --> 00:30:42,167 Is the only place 769 00:30:42,167 --> 00:30:44,167 That you'll find populations 770 00:30:44,167 --> 00:30:47,834 Of red deer. 771 00:30:47,834 --> 00:30:49,867 We also find Russian wild boars 772 00:30:49,867 --> 00:30:51,934 That the populations in the zone 773 00:30:51,934 --> 00:30:53,967 Are 10 to 15 times higher 774 00:30:53,967 --> 00:30:55,101 Than they are outside 775 00:30:55,101 --> 00:31:04,101 Of the zone. 776 00:31:04,167 --> 00:31:05,134 [speaking Russian] 777 00:31:05,134 --> 00:31:06,234 we're now at the kindergarten 778 00:31:06,234 --> 00:31:08,334 Of Karachi village, not far 779 00:31:08,334 --> 00:31:10,134 From the Chernobyl station. 780 00:31:10,134 --> 00:31:11,434 Children were living here 781 00:31:11,434 --> 00:31:13,267 While their parents worked. 782 00:31:13,267 --> 00:31:14,201 But after that night 783 00:31:14,201 --> 00:31:16,034 In April 1986, 784 00:31:16,034 --> 00:31:20,501 They never returned. 785 00:31:23,067 --> 00:31:24,800 We are in what was formerly 786 00:31:24,800 --> 00:31:26,633 A bedroom in this kindergarten 787 00:31:26,633 --> 00:31:27,767 Where children used to sleep 788 00:31:27,767 --> 00:31:30,733 And rest. 789 00:31:30,733 --> 00:31:31,134 Now, there's 790 00:31:31,134 --> 00:31:34,167 Certain emptiness here. 791 00:31:34,167 --> 00:31:36,234 All these windows are broken. 792 00:31:36,234 --> 00:31:37,201 But the room continues 793 00:31:37,201 --> 00:31:42,267 To live on. 794 00:31:42,267 --> 00:31:42,767 Birds fly in here 795 00:31:42,767 --> 00:31:45,034 And sit on these bars. 796 00:31:45,034 --> 00:31:46,201 We even found evidence 797 00:31:46,201 --> 00:31:48,267 That an owl comes here. 798 00:31:48,267 --> 00:31:50,334 An owl, it regurgitates food, 799 00:31:50,334 --> 00:31:54,167 Fur, bones, and feathers. 800 00:31:54,167 --> 00:31:55,534 Evidently, it likes to sit here 801 00:31:55,534 --> 00:31:57,134 On this window pane. 802 00:31:57,134 --> 00:31:58,568 So this room continues 803 00:31:58,568 --> 00:32:12,767 To maintain life. 804 00:32:12,767 --> 00:32:14,201 Even trees which had proven 805 00:32:14,201 --> 00:32:15,667 Especially vulnerable 806 00:32:15,667 --> 00:32:17,733 To radioactive fallout. 807 00:32:17,733 --> 00:32:19,234 Are finding new homes 808 00:32:19,234 --> 00:32:26,101 In the evacuation zone. 809 00:32:26,167 --> 00:32:26,667 I'm sitting 810 00:32:26,667 --> 00:32:28,568 In the pipit soccer stadium 811 00:32:28,568 --> 00:32:30,000 Where, 20 years ago, 812 00:32:30,000 --> 00:32:31,201 Hundreds of people would come 813 00:32:31,201 --> 00:32:31,767 And cheer 814 00:32:31,767 --> 00:32:36,301 On their favorite team. 815 00:32:38,468 --> 00:32:39,633 You can imagine the laughter 816 00:32:39,633 --> 00:32:40,334 Of the sounds 817 00:32:40,334 --> 00:32:43,700 Of the crowds here. 818 00:32:43,700 --> 00:32:45,401 The activity on the field 819 00:32:45,401 --> 00:32:47,334 Which, 20 years later, 820 00:32:47,334 --> 00:32:58,501 Is barely discernable. 821 00:32:58,501 --> 00:33:00,000 The soccer field now is going 822 00:33:00,000 --> 00:33:01,034 Through succession 823 00:33:01,034 --> 00:33:02,934 As you would expect in returning 824 00:33:02,934 --> 00:33:05,101 To what it was originally 825 00:33:05,101 --> 00:33:06,367 Hundreds of years ago 826 00:33:06,367 --> 00:33:07,167 Which was a mixed? 827 00:33:07,167 --> 00:33:15,600 Deciduous forest. 828 00:33:15,600 --> 00:33:16,733 I grew up in a town 829 00:33:16,733 --> 00:33:18,301 About like this 830 00:33:18,301 --> 00:33:19,600 And I used to enjoy 831 00:33:19,600 --> 00:33:22,134 Riding bumper cars like these 832 00:33:22,134 --> 00:33:24,967 About a half a world away. 833 00:33:24,967 --> 00:33:26,534 And it seems pretty sad 834 00:33:26,534 --> 00:33:27,501 When you look now 835 00:33:27,501 --> 00:33:28,600 And you see what's become 836 00:33:28,600 --> 00:33:29,867 Of this beautiful city 837 00:33:29,867 --> 00:33:31,967 Of pipit and that people 838 00:33:31,967 --> 00:33:41,600 Will never live here again. 839 00:33:41,600 --> 00:33:42,367 But there's another side 840 00:33:42,367 --> 00:33:43,633 To this story, 841 00:33:43,633 --> 00:33:45,667 A very encouraging side; 842 00:33:45,667 --> 00:33:47,600 One that says that life 843 00:33:47,600 --> 00:33:49,234 Is much more resilient 844 00:33:49,234 --> 00:33:51,367 Than what we thought possible. 845 00:33:51,367 --> 00:33:54,101 That in the absence of man, 846 00:33:54,101 --> 00:33:55,733 That life will continue 847 00:33:55,733 --> 00:33:57,600 And that life will thrive 848 00:33:57,600 --> 00:34:01,867 And that the legacy of life 849 00:34:01,867 --> 00:34:03,501 Will always be here, 850 00:34:03,501 --> 00:34:06,367 Because we are a part of life. 851 00:34:06,367 --> 00:34:08,167 Even if we disappear, 852 00:34:08,167 --> 00:34:09,234 Our legacy of life 853 00:34:09,234 --> 00:34:10,800 Will continue. 854 00:34:10,900 --> 00:34:13,833 [music] 855 00:34:45,066 --> 00:34:47,665 Through decaying neighborhoods 856 00:34:47,665 --> 00:34:53,732 In search of their next meal. 857 00:34:53,732 --> 00:34:54,999 In some of the great cities 858 00:34:54,999 --> 00:34:56,366 Of the world, 859 00:34:56,366 --> 00:34:57,966 Solid ground is getting harder 860 00:34:57,966 --> 00:35:02,399 To find. 861 00:35:02,399 --> 00:35:04,032 In the time of humans, 862 00:35:04,032 --> 00:35:05,133 London was protected 863 00:35:05,133 --> 00:35:06,500 From tidal surges 864 00:35:06,500 --> 00:35:09,032 By 10 retractable steel gates 865 00:35:09,032 --> 00:35:09,765 That could be raised 866 00:35:09,765 --> 00:35:11,566 During storms to seal off 867 00:35:11,566 --> 00:35:12,699 The Thames River 868 00:35:12,699 --> 00:35:16,832 From the North Sea. 869 00:35:16,832 --> 00:35:17,600 Without humans 870 00:35:17,600 --> 00:35:20,233 To operate the barrier, 871 00:35:20,233 --> 00:35:28,199 London is defenseless. 872 00:35:28,199 --> 00:35:30,333 Another low-lying city, 873 00:35:30,333 --> 00:35:31,466 Amsterdam, 874 00:35:31,466 --> 00:35:46,699 Meets the same watery fate. 875 00:35:46,699 --> 00:35:49,399 In a New York City high rise, 876 00:35:49,399 --> 00:35:50,899 Some windows have already 877 00:35:50,899 --> 00:35:53,233 Cracked and slipped loose 878 00:35:53,233 --> 00:35:56,899 From their frames and many more 879 00:35:56,899 --> 00:36:01,133 Are on the verge of destruction. 880 00:36:01,133 --> 00:36:02,333 After a quarter century 881 00:36:02,333 --> 00:36:03,899 Of exposure to moisture 882 00:36:03,899 --> 00:36:06,333 And heat without maintenance, 883 00:36:06,333 --> 00:36:07,765 The normally flexible window 884 00:36:07,765 --> 00:36:09,866 Sealant has become rigid, 885 00:36:09,866 --> 00:36:10,932 Locking this window 886 00:36:10,932 --> 00:36:13,266 To its frame. 887 00:36:13,266 --> 00:36:14,799 As the metal frame expands 888 00:36:14,799 --> 00:36:16,333 And contracts with changes 889 00:36:16,333 --> 00:36:18,999 In temperature, 890 00:36:18,999 --> 00:36:19,999 It induces stresses 891 00:36:19,999 --> 00:36:21,466 On the glass. 892 00:36:21,466 --> 00:36:23,133 It cracks and plummets 893 00:36:23,133 --> 00:36:27,999 To the sidewalk below. 894 00:36:28,066 --> 00:36:29,665 after a few of the windows 895 00:36:29,665 --> 00:36:31,133 Fall out of a building 896 00:36:31,133 --> 00:36:32,199 Like this, 897 00:36:32,199 --> 00:36:33,899 Then the wind pressure effect 898 00:36:33,899 --> 00:36:35,266 Changes dramatically. 899 00:36:35,399 --> 00:36:36,732 As well as external pressure 900 00:36:36,732 --> 00:36:37,899 Coming on to the building, 901 00:36:37,899 --> 00:36:39,366 You also get suction. 902 00:36:39,366 --> 00:36:40,765 And that aggravates the problem 903 00:36:40,765 --> 00:36:42,333 So more of the panels 904 00:36:42,333 --> 00:36:47,765 Are likely to fall out. 905 00:36:47,765 --> 00:36:48,999 through these gaping holes, 906 00:36:48,999 --> 00:36:49,966 The building fills 907 00:36:49,966 --> 00:36:57,566 With windswept debris. 908 00:36:57,566 --> 00:37:02,665 A summer storm rolls in. 909 00:37:02,665 --> 00:37:04,199 On top of the structure, 910 00:37:04,199 --> 00:37:05,632 The copper-lightning deterrent 911 00:37:05,632 --> 00:37:07,166 System that once protected 912 00:37:07,166 --> 00:37:09,066 Thousands of office workers 913 00:37:09,066 --> 00:37:17,632 Is now corroded and useless. 914 00:37:17,632 --> 00:37:19,299 A lightning bolt turns the tower 915 00:37:19,299 --> 00:37:34,333 Into a raging inferno. 916 00:37:34,333 --> 00:37:35,665 The gutted building makes 917 00:37:35,665 --> 00:37:36,866 The perfect home 918 00:37:36,866 --> 00:37:44,399 For a surprising survivor. 919 00:37:44,399 --> 00:37:45,533 Although pigeons once relied 920 00:37:45,533 --> 00:37:48,966 On the handouts of humans, 921 00:37:48,966 --> 00:37:50,433 They have done just fine 922 00:37:50,433 --> 00:37:55,799 In 25 years without us. 923 00:37:55,799 --> 00:37:57,799 pigeons are survivors. 924 00:37:57,799 --> 00:37:58,632 They can live in the wild; 925 00:37:58,632 --> 00:38:00,500 They do live in the wild still. 926 00:38:00,566 --> 00:38:02,433 And in a period 927 00:38:02,433 --> 00:38:03,932 Where there were no people 928 00:38:03,932 --> 00:38:05,765 But there still were edifices 929 00:38:05,765 --> 00:38:07,600 And artifacts, our buildings, 930 00:38:07,732 --> 00:38:08,632 They would do very well 931 00:38:08,632 --> 00:38:10,032 Because they would adopt these 932 00:38:10,032 --> 00:38:10,732 As kind of 933 00:38:10,732 --> 00:38:12,133 Artificial cliff faces, 934 00:38:12,133 --> 00:38:13,133 Which is what they really are? 935 00:38:13,133 --> 00:38:17,399 Adapted to. 936 00:38:17,399 --> 00:38:22,032 like the pigeon, 937 00:38:22,032 --> 00:38:23,266 The disappearance of humans 938 00:38:23,266 --> 00:38:24,665 Forced a change in the habits 939 00:38:24,665 --> 00:38:28,066 Of the lowly cockroach. 940 00:38:28,133 --> 00:38:30,133 think of the poor cockroach 941 00:38:30,133 --> 00:38:30,966 After they gorge 942 00:38:30,966 --> 00:38:32,600 Upon our surplus 943 00:38:32,600 --> 00:38:35,032 When we're gone, 944 00:38:35,032 --> 00:38:37,233 They'll mourn us. 945 00:38:37,366 --> 00:38:38,799 They'll be sorry. 946 00:38:38,799 --> 00:38:40,133 but the morning won't last 947 00:38:40,133 --> 00:38:42,665 For long. 948 00:38:42,665 --> 00:38:43,799 While cockroaches thrived 949 00:38:43,799 --> 00:38:45,399 On our scraps, 950 00:38:45,399 --> 00:38:47,333 They can also eat bookbinding's, 951 00:38:47,333 --> 00:38:49,166 And cardboard, 952 00:38:49,166 --> 00:38:51,066 And any rotting organic matter 953 00:38:51,066 --> 00:38:55,099 Including dead leaves and roots. 954 00:38:55,099 --> 00:38:57,099 While food isn't a problem, 955 00:38:57,099 --> 00:39:00,099 Roaches also need warmth; 956 00:39:00,099 --> 00:39:00,999 The kind that humans 957 00:39:00,999 --> 00:39:02,233 Had always supplied 958 00:39:02,233 --> 00:39:06,732 Through artificial heat. 959 00:39:06,732 --> 00:39:07,732 Cockroaches started 960 00:39:07,732 --> 00:39:10,166 As a tropical species 961 00:39:10,166 --> 00:39:11,233 And some experts say 962 00:39:11,233 --> 00:39:12,732 They couldn't survive the winter 963 00:39:12,732 --> 00:39:16,533 In colder cities. 964 00:39:16,533 --> 00:39:17,366 But it's hard to bet 965 00:39:17,366 --> 00:39:18,832 Against a creature that has seen 966 00:39:18,832 --> 00:39:22,433 The dinosaurs come and go. 967 00:39:22,433 --> 00:39:23,266 cockroaches are 968 00:39:23,266 --> 00:39:25,066 Extremely adaptable. 969 00:39:25,066 --> 00:39:25,632 They've been around 970 00:39:25,632 --> 00:39:26,966 For 300 million years. 971 00:39:26,966 --> 00:39:27,665 If I have to bet, 972 00:39:27,665 --> 00:39:28,765 I'd put my money on them 973 00:39:28,765 --> 00:39:29,866 Being able to survive 974 00:39:29,866 --> 00:39:35,732 In one form or another. 975 00:39:35,732 --> 00:39:36,466 the first winter 976 00:39:36,466 --> 00:39:38,066 After humans did witness 977 00:39:38,066 --> 00:39:41,699 The die-off of some cockroaches, 978 00:39:41,699 --> 00:39:43,366 But many more moved underground 979 00:39:43,366 --> 00:39:44,899 To find warmth until 980 00:39:44,899 --> 00:39:49,732 Milder temperatures returned. 981 00:39:49,732 --> 00:39:51,600 In an abandoned downtown 982 00:39:51,600 --> 00:39:53,533 Devoid of insecticides, 983 00:39:53,533 --> 00:39:55,233 Overrun by vegetation 984 00:39:55,233 --> 00:39:58,133 And with a rising water table, 985 00:39:58,133 --> 00:40:00,233 This former pest is now enjoying 986 00:40:00,233 --> 00:40:11,500 A golden age. 987 00:40:11,500 --> 00:40:13,032 Cockroaches were only a nuisance 988 00:40:13,032 --> 00:40:16,999 To humans, 989 00:40:16,999 --> 00:40:23,066 But wolves were a terror. 990 00:40:23,066 --> 00:40:25,866 So man hunted them mercilessly. 991 00:40:25,866 --> 00:40:27,500 When the first European settlers 992 00:40:27,500 --> 00:40:28,600 Arrived in what is now 993 00:40:28,600 --> 00:40:30,333 The United States, 994 00:40:30,333 --> 00:40:31,500 It's believed nearly half 995 00:40:31,500 --> 00:40:32,600 A million wolves roamed 996 00:40:32,600 --> 00:40:35,166 The country side. 997 00:40:35,166 --> 00:40:36,799 By the 20th century, 998 00:40:36,799 --> 00:40:37,632 These predators 999 00:40:37,632 --> 00:40:38,966 Were nearly extinct 1000 00:40:38,966 --> 00:40:42,899 In the lower 48 states. 1001 00:40:42,899 --> 00:40:44,500 Now, with no humans left 1002 00:40:44,500 --> 00:40:45,866 To battle them, 1003 00:40:45,866 --> 00:40:47,533 Wolf populations multiply 1004 00:40:47,533 --> 00:40:50,899 By as much six times each year. 1005 00:40:50,899 --> 00:40:51,932 Within 25 years 1006 00:40:51,932 --> 00:40:53,533 Of our disappearance, 1007 00:40:53,533 --> 00:40:54,932 There could easily be half 1008 00:40:54,932 --> 00:40:56,133 A million of them roaming 1009 00:40:56,133 --> 00:41:02,999 The united states again. 1010 00:41:02,999 --> 00:41:04,399 This amazing comeback 1011 00:41:04,399 --> 00:41:05,166 Has been seen 1012 00:41:05,166 --> 00:41:08,699 On a small scale before. 1013 00:41:08,699 --> 00:41:11,966 In 1995, biologists released 1014 00:41:11,966 --> 00:41:13,399 A few dozen wolves 1015 00:41:13,399 --> 00:41:14,366 Within the boundaries 1016 00:41:14,366 --> 00:41:18,266 Of yellow stone national park; 1017 00:41:18,266 --> 00:41:18,899 A place 1018 00:41:18,899 --> 00:41:19,799 Where they would be protected 1019 00:41:19,799 --> 00:41:32,333 From persecution by humans. 1020 00:41:32,333 --> 00:41:33,433 Within a decade, 1021 00:41:33,433 --> 00:41:34,932 A few dozen had multiplied 1022 00:41:34,932 --> 00:41:37,665 Into 1,500 1023 00:41:37,665 --> 00:41:38,299 And the wolves 1024 00:41:38,299 --> 00:41:39,099 Quickly spread out 1025 00:41:39,099 --> 00:41:40,699 From their release point 1026 00:41:40,699 --> 00:41:41,932 To occupy territory 1027 00:41:41,932 --> 00:41:42,765 Throughout the states 1028 00:41:42,765 --> 00:41:50,399 Of Wyoming, Montana, and Idaho. 1029 00:41:50,399 --> 00:41:51,632 it would be fast 1030 00:41:51,632 --> 00:41:52,433 If you can start 1031 00:41:52,433 --> 00:41:53,899 With just a few dozen wolves 1032 00:41:53,899 --> 00:41:55,466 And in the course of one decade, 1033 00:41:55,466 --> 00:41:57,765 Have a population of 1,500 1034 00:41:57,765 --> 00:41:58,366 And you could have 1035 00:41:58,366 --> 00:41:59,866 A geographic expansion 1036 00:41:59,932 --> 00:42:01,466 Where they filled up a big chunk 1037 00:42:01,466 --> 00:42:02,765 Of a three-state area. 1038 00:42:02,765 --> 00:42:03,299 And these are 1039 00:42:03,299 --> 00:42:04,765 Big western states. 1040 00:42:04,765 --> 00:42:05,665 Yeah, when the conditions 1041 00:42:05,665 --> 00:42:06,366 Are right, 1042 00:42:06,366 --> 00:42:07,233 They can re-colonize 1043 00:42:07,233 --> 00:42:10,732 Pretty rapidly. 1044 00:42:10,866 --> 00:42:12,133 Could we see them in Manhattan? 1045 00:42:12,133 --> 00:42:15,133 Or Chicago? 1046 00:42:15,133 --> 00:42:16,566 As soon as the deer get there, 1047 00:42:16,566 --> 00:42:17,366 The wolves will be right 1048 00:42:17,366 --> 00:42:25,966 Behind them. 1049 00:42:25,966 --> 00:42:26,699 animals haven't 1050 00:42:26,699 --> 00:42:28,799 Just been hunted by humans; 1051 00:42:28,799 --> 00:42:38,600 They've also been hemmed in. 1052 00:42:38,600 --> 00:42:39,866 There are roughly three million 1053 00:42:39,866 --> 00:42:41,333 Miles of paved road 1054 00:42:41,333 --> 00:42:46,399 In the united states alone. 1055 00:42:46,399 --> 00:42:47,799 And it's no coincidence 1056 00:42:47,799 --> 00:42:48,899 That many of them cut 1057 00:42:48,899 --> 00:42:50,099 Right through the paths 1058 00:42:50,099 --> 00:42:51,999 Animals use to get from place 1059 00:42:51,999 --> 00:42:54,799 To place. 1060 00:42:54,799 --> 00:42:55,632 the things that make 1061 00:42:55,632 --> 00:42:56,433 A landscape good 1062 00:42:56,433 --> 00:42:58,832 For animal movement 1063 00:42:58,832 --> 00:43:00,133 Also make it easy to engineer 1064 00:43:00,133 --> 00:43:04,066 A road in that location. 1065 00:43:04,066 --> 00:43:05,866 So, we've cut off pretty much 1066 00:43:05,866 --> 00:43:07,066 All major migrations 1067 00:43:07,066 --> 00:43:12,632 In North America. 1068 00:43:12,632 --> 00:43:14,066 asphalt and automobiles 1069 00:43:14,066 --> 00:43:15,765 Wreaked particular havoc 1070 00:43:15,765 --> 00:43:24,333 On the grizzly bear. 1071 00:43:24,333 --> 00:43:24,999 Their habitat 1072 00:43:24,999 --> 00:43:27,765 Was so carved up by roads 1073 00:43:27,765 --> 00:43:28,433 That they're confined 1074 00:43:28,433 --> 00:43:30,966 To isolated pockets, 1075 00:43:30,966 --> 00:43:31,533 Cutting them off 1076 00:43:31,533 --> 00:43:32,832 From food sources 1077 00:43:32,832 --> 00:43:41,233 And potential mates. 1078 00:43:41,233 --> 00:43:43,600 In a life after humans, 1079 00:43:43,600 --> 00:43:45,299 Roads are no longer barriers 1080 00:43:45,299 --> 00:43:47,632 For the grizzly. 1081 00:43:47,632 --> 00:43:50,366 Instead they are pathways; 1082 00:43:50,366 --> 00:43:51,500 Trails that lead them back 1083 00:43:51,500 --> 00:43:52,433 Into the heart 1084 00:43:52,433 --> 00:44:04,899 Of their former range. 1085 00:44:04,899 --> 00:44:08,133 forty years after people. 1086 00:44:08,133 --> 00:44:09,366 While cities of steel 1087 00:44:09,366 --> 00:44:10,199 And concrete 1088 00:44:10,199 --> 00:44:13,500 Are still standing tall, 1089 00:44:13,500 --> 00:44:18,166 The suburbs are under attack. 1090 00:44:18,166 --> 00:44:20,099 Roughly 90 percent of all homes 1091 00:44:20,099 --> 00:44:21,466 In the United States 1092 00:44:21,466 --> 00:44:24,765 Have wood frames. 1093 00:44:24,765 --> 00:44:30,600 While some have burned, 1094 00:44:30,600 --> 00:44:39,032 Others are now being devoured. 1095 00:44:39,032 --> 00:44:41,433 Without paint and preservatives, 1096 00:44:41,433 --> 00:44:42,466 The lumber of homes 1097 00:44:42,466 --> 00:44:46,932 Is defenseless against termites. 1098 00:44:46,932 --> 00:44:49,133 Termites feast on cellulose, 1099 00:44:49,133 --> 00:44:50,366 The basic building block 1100 00:44:50,366 --> 00:44:52,366 Of wood. 1101 00:44:52,366 --> 00:44:53,533 And their appetites 1102 00:44:53,533 --> 00:44:56,233 Are relentless. 1103 00:44:56,233 --> 00:44:57,399 Some colonies can eat 1104 00:44:57,399 --> 00:44:59,732 As much as 1,000 pounds of wood 1105 00:44:59,732 --> 00:45:04,932 Per year. 1106 00:45:04,932 --> 00:45:06,866 In this destructive advance, 1107 00:45:06,866 --> 00:45:07,566 The termites 1108 00:45:07,566 --> 00:45:09,333 Aren't working alone. 1109 00:45:09,333 --> 00:45:09,999 the process we know 1110 00:45:09,999 --> 00:45:11,333 As rotting will occur 1111 00:45:11,333 --> 00:45:12,566 When the wood gets exposed 1112 00:45:12,566 --> 00:45:15,233 To the elements. 1113 00:45:15,299 --> 00:45:16,500 And this rotting, actually, 1114 00:45:16,500 --> 00:45:18,799 Is a more complicated process. 1115 00:45:18,932 --> 00:45:20,166 It's a process by which microbes 1116 00:45:20,166 --> 00:45:21,233 Attack the wood 1117 00:45:21,233 --> 00:45:22,533 And release carbon dioxide 1118 00:45:22,533 --> 00:45:24,732 And methane to the atmosphere. 1119 00:45:24,732 --> 00:45:26,166 If humans were to leave, 1120 00:45:26,166 --> 00:45:27,099 It'd be a matter of decades 1121 00:45:27,099 --> 00:45:28,166 Before most structures 1122 00:45:28,166 --> 00:45:28,699 That had significant 1123 00:45:28,699 --> 00:45:29,765 Wood components 1124 00:45:29,765 --> 00:45:32,832 Would start to decay. 1125 00:45:32,832 --> 00:45:33,500 faced with 1126 00:45:33,500 --> 00:45:34,665 A two pronged attack 1127 00:45:34,665 --> 00:45:36,899 From termites and rot, 1128 00:45:36,899 --> 00:45:38,632 The beams that hold up the roof 1129 00:45:38,632 --> 00:45:41,233 Give way. 1130 00:45:41,233 --> 00:45:42,099 And the boundary 1131 00:45:42,099 --> 00:45:43,832 Between inside and out, 1132 00:45:43,832 --> 00:45:45,566 That had once been so important 1133 00:45:45,566 --> 00:45:46,399 To the humans 1134 00:45:46,399 --> 00:45:49,566 Who called this building home? 1135 00:45:49,566 --> 00:45:53,533 Is forever erased. 1136 00:45:53,533 --> 00:45:54,399 other substances 1137 00:45:54,399 --> 00:45:55,500 Like this mortar and rock 1138 00:45:55,500 --> 00:45:56,899 Are going to last longer 1139 00:45:56,899 --> 00:45:58,266 Than several decades, 1140 00:45:58,266 --> 00:45:59,665 But they'll still crumble 1141 00:45:59,665 --> 00:46:00,765 After natural, chemical, 1142 00:46:00,765 --> 00:46:01,500 And physical weathering 1143 00:46:01,500 --> 00:46:02,366 Processes, 1144 00:46:02,366 --> 00:46:03,466 And eventually these walls 1145 00:46:03,466 --> 00:46:05,032 Will fall down as well, 1146 00:46:05,032 --> 00:46:10,199 And there'll be no remnants. 1147 00:46:10,199 --> 00:46:12,433 now, nature will act quickly 1148 00:46:12,433 --> 00:46:16,299 To swallow up these ruins. 1149 00:46:16,299 --> 00:46:17,433 This crumbling house 1150 00:46:17,433 --> 00:46:19,966 In Baltimore's druid hill park 1151 00:46:19,966 --> 00:46:21,533 Was once home to the caretaker? 1152 00:46:21,533 --> 00:46:23,665 Of the city zoo. 1153 00:46:23,665 --> 00:46:24,466 it looks like this building 1154 00:46:24,466 --> 00:46:25,233 Has been abandoned 1155 00:46:25,233 --> 00:46:26,966 For more than a hundred years. 1156 00:46:26,966 --> 00:46:27,732 But in reality, 1157 00:46:27,732 --> 00:46:28,899 People have been living here 1158 00:46:28,899 --> 00:46:31,166 Up till 40 years ago. 1159 00:46:31,166 --> 00:46:32,066 It's amazing how quickly 1160 00:46:32,066 --> 00:46:33,932 The vegetation has reclaimed 1161 00:46:33,932 --> 00:46:34,732 The area. 1162 00:46:34,732 --> 00:46:36,333 The vines have started to climb 1163 00:46:36,333 --> 00:46:37,899 Up the walls. 1164 00:46:37,899 --> 00:46:38,732 The trees are growing 1165 00:46:38,732 --> 00:46:40,133 Into the structure, 1166 00:46:40,133 --> 00:46:41,166 And they're both physically 1167 00:46:41,166 --> 00:46:42,533 Pulling the structure apart, 1168 00:46:42,533 --> 00:46:46,699 And chemically dissolving it. 1169 00:46:46,699 --> 00:46:48,299 structures built entirely 1170 00:46:48,299 --> 00:46:49,765 Of stone or masonry 1171 00:46:49,765 --> 00:46:50,899 Will far outlive 1172 00:46:50,899 --> 00:46:54,366 Anything made of wood. 1173 00:46:54,366 --> 00:46:55,399 Exactly how fast 1174 00:46:55,399 --> 00:46:56,866 They will crumble depends 1175 00:46:56,866 --> 00:47:03,500 On their environment. 1176 00:47:03,566 --> 00:47:04,399 the coast of Maine, really, 1177 00:47:04,399 --> 00:47:07,333 Isn't very kind to buildings. 1178 00:47:07,333 --> 00:47:08,233 Structures out here 1179 00:47:08,233 --> 00:47:09,099 Don't so much decay 1180 00:47:09,099 --> 00:47:10,299 When you live them alone; 1181 00:47:10,299 --> 00:47:12,765 They melt. 1182 00:47:12,899 --> 00:47:13,566 these structures 1183 00:47:13,566 --> 00:47:15,399 On black island, Maine 1184 00:47:15,399 --> 00:47:16,266 Used to be part 1185 00:47:16,266 --> 00:47:18,399 Of granite quarry whose stone 1186 00:47:18,399 --> 00:47:19,932 Was used to build and decorate 1187 00:47:19,932 --> 00:47:22,099 Cities like Boston, New York, 1188 00:47:22,099 --> 00:47:25,899 And Philadelphia. 1189 00:47:25,899 --> 00:47:29,466 It was abandoned around 1920. 1190 00:47:29,466 --> 00:47:30,299 here, the buildings 1191 00:47:30,299 --> 00:47:31,032 Have all vanished 1192 00:47:31,032 --> 00:47:31,765 Within the space 1193 00:47:31,765 --> 00:47:33,932 Of 80 and 90 years. 1194 00:47:33,932 --> 00:47:39,999 There's almost nothing left. 1195 00:47:39,999 --> 00:47:41,600 in the right conditions 1196 00:47:41,600 --> 00:47:43,600 And with human maintenance, 1197 00:47:43,600 --> 00:47:45,166 Stone construction can last 1198 00:47:45,166 --> 00:47:49,266 For thousands of years. 1199 00:47:49,266 --> 00:47:51,166 In some places in Europe, 1200 00:47:51,166 --> 00:47:52,632 Ancient roman aqueducts 1201 00:47:52,632 --> 00:47:54,999 Are still in use. 1202 00:47:54,999 --> 00:47:56,832 But without maintenance, 1203 00:47:56,832 --> 00:47:58,600 Stone can fall victim 1204 00:47:58,600 --> 00:48:01,366 To a very stealthy enemy. 1205 00:48:01,433 --> 00:48:02,099 one of the great enemies 1206 00:48:02,099 --> 00:48:03,433 Of stone are actually salts 1207 00:48:03,433 --> 00:48:04,732 And salt crystals. 1208 00:48:04,732 --> 00:48:06,199 Even thousands of years ago, 1209 00:48:06,333 --> 00:48:07,466 People notice the effect 1210 00:48:07,466 --> 00:48:09,166 That salts had on deteriorating 1211 00:48:09,166 --> 00:48:13,832 The ancient pyramids. 1212 00:48:13,832 --> 00:48:14,932 there are many ways 1213 00:48:14,932 --> 00:48:17,066 Salts infiltrate stone buildings 1214 00:48:17,066 --> 00:48:18,500 And monuments: 1215 00:48:18,500 --> 00:48:21,032 Polluted air, seawater, 1216 00:48:21,032 --> 00:48:24,233 And even bird droppings. 1217 00:48:24,233 --> 00:48:25,266 soluble salts dissolve 1218 00:48:25,266 --> 00:48:25,999 In water, 1219 00:48:25,999 --> 00:48:27,133 And as the water evaporates, 1220 00:48:27,133 --> 00:48:28,966 It will rise up inside 1221 00:48:28,966 --> 00:48:30,665 Of porous building materials; 1222 00:48:30,665 --> 00:48:32,266 Things like brick and stone 1223 00:48:32,266 --> 00:48:33,466 And even concrete. 1224 00:48:33,466 --> 00:48:35,500 And what happen are the salts 1225 00:48:35,500 --> 00:48:36,665 Will continue to grow 1226 00:48:36,665 --> 00:48:38,999 Inside the pores of the stone 1227 00:48:38,999 --> 00:48:40,133 Until they come up 1228 00:48:40,133 --> 00:48:42,333 Against the side of the wall, 1229 00:48:42,333 --> 00:48:43,466 And they'll actually push 1230 00:48:43,466 --> 00:48:48,133 The stone apart. 1231 00:48:48,133 --> 00:48:48,765 what we're seeing 1232 00:48:48,765 --> 00:48:49,866 In this time-lapse video 1233 00:48:49,866 --> 00:48:51,466 Really shows the rapid decay 1234 00:48:51,466 --> 00:48:52,966 Of the stone in response 1235 00:48:52,966 --> 00:48:57,866 To this deterioration by salts. 1236 00:48:57,866 --> 00:48:58,732 In this experiment, 1237 00:48:58,732 --> 00:49:00,099 It took about three weeks to go 1238 00:49:00,099 --> 00:49:05,699 From this piece of stone 1239 00:49:05,699 --> 00:49:07,299 To this piece of stone, 1240 00:49:07,299 --> 00:49:09,333 Which is completely deteriorated? 1241 00:49:09,333 --> 00:49:10,566 By sodium sulfate 1242 00:49:10,566 --> 00:49:12,166 Crystallization. 1243 00:49:12,166 --> 00:49:13,566 three weeks in this 1244 00:49:13,566 --> 00:49:16,099 Accelerated aging chamber 1245 00:49:16,099 --> 00:49:17,966 Are equivalent to a few years 1246 00:49:17,966 --> 00:49:20,399 In the harshest of environments, 1247 00:49:20,399 --> 00:49:22,299 Or a few decades in a more 1248 00:49:22,299 --> 00:49:24,600 Benign desert climate. 1249 00:49:24,600 --> 00:49:25,299 if we could see 1250 00:49:25,299 --> 00:49:26,433 Microscopically what's going on? 1251 00:49:26,433 --> 00:49:28,732 Inside the pyramids, 1252 00:49:28,732 --> 00:49:29,333 This is what 1253 00:49:29,333 --> 00:49:30,233 Would be taking place. 1254 00:49:30,233 --> 00:49:31,299 You can actually see the salts 1255 00:49:31,299 --> 00:49:36,266 Deteriorate the stone. 1256 00:49:36,266 --> 00:49:38,732 although not immune to decay, 1257 00:49:38,732 --> 00:49:39,999 The pyramids have survived 1258 00:49:39,999 --> 00:49:42,466 For nearly 5,000 years 1259 00:49:42,466 --> 00:49:44,600 Because of their sheer volume 1260 00:49:44,600 --> 00:49:45,399 And their hot, 1261 00:49:45,399 --> 00:49:48,299 Dry desert environment. 1262 00:49:48,299 --> 00:49:49,966 Too massive to be destroyed 1263 00:49:49,966 --> 00:49:52,899 By either man or nature, 1264 00:49:52,899 --> 00:49:54,233 The pyramids of Giza 1265 00:49:54,233 --> 00:49:55,366 Were the only one 1266 00:49:55,366 --> 00:49:56,600 Of the seven wonders 1267 00:49:56,600 --> 00:49:58,932 Of the ancient world to survive 1268 00:49:58,932 --> 00:50:01,299 Into the modern era. 1269 00:50:01,299 --> 00:50:02,832 Many ancient monuments 1270 00:50:02,832 --> 00:50:03,932 Have survived only 1271 00:50:03,932 --> 00:50:05,600 Because of human maintenance 1272 00:50:05,600 --> 00:50:10,366 Throughout the centuries. 1273 00:50:10,366 --> 00:50:11,765 The sphinx was uncovered 1274 00:50:11,765 --> 00:50:13,699 And restored for the first time 1275 00:50:13,699 --> 00:50:16,899 Back in 1400 back. 1276 00:50:16,899 --> 00:50:18,433 Modern experts who have studied 1277 00:50:18,433 --> 00:50:20,066 The sphinx, predict 1278 00:50:20,066 --> 00:50:22,199 That without human intervention, 1279 00:50:22,199 --> 00:50:24,032 Deterioration from salts 1280 00:50:24,032 --> 00:50:26,032 And wind erosion could render it 1281 00:50:26,032 --> 00:50:27,466 A pile of dust 1282 00:50:27,466 --> 00:50:36,765 Within 500 to 1,000 years. 1283 00:50:36,765 --> 00:50:38,799 The largest concrete structures 1284 00:50:38,799 --> 00:50:40,866 Like hover dam, will last 1285 00:50:40,866 --> 00:50:48,066 Even longer than that. 1286 00:50:48,066 --> 00:50:49,399 Hover is so thick 1287 00:50:49,399 --> 00:50:50,765 That over 70 years 1288 00:50:50,765 --> 00:50:52,500 After it was constructed 1289 00:50:52,500 --> 00:50:54,032 The concrete deep inside 1290 00:50:54,032 --> 00:50:59,366 Was still curing. 1291 00:50:59,366 --> 00:51:01,333 But of the 15 tallest dams 1292 00:51:01,333 --> 00:51:03,233 In the United States, 1293 00:51:03,233 --> 00:51:05,966 Only 10 are concrete. 1294 00:51:05,966 --> 00:51:07,765 The others are made of compacted 1295 00:51:07,765 --> 00:51:09,632 Rock or earth, 1296 00:51:09,632 --> 00:51:10,932 Like northern California's 1297 00:51:10,932 --> 00:51:14,932 Trinity dam. 1298 00:51:14,932 --> 00:51:16,866 If there were humans around, 1299 00:51:16,866 --> 00:51:18,199 This leak in the dam would get 1300 00:51:18,199 --> 00:51:21,600 An emergency fix. 1301 00:51:21,600 --> 00:51:25,732 But those days are long gone. 1302 00:51:25,799 --> 00:51:26,799 some of these dams 1303 00:51:26,799 --> 00:51:29,399 Are absolutely enormous. 1304 00:51:29,399 --> 00:51:30,399 And if they fail, 1305 00:51:30,399 --> 00:51:31,966 As they will in time, 1306 00:51:31,966 --> 00:51:33,399 Then the surge of water 1307 00:51:33,399 --> 00:51:35,166 That falls in behind them 1308 00:51:35,166 --> 00:51:36,266 And cascades 1309 00:51:36,266 --> 00:51:38,632 Down a valley below 1310 00:51:38,632 --> 00:51:40,266 Would have a huge force, 1311 00:51:40,266 --> 00:51:41,333 Big enough to sweep away 1312 00:51:41,333 --> 00:51:45,966 Everything on its path. 1313 00:51:55,799 --> 00:51:58,399 fifty years after humans, 1314 00:51:58,399 --> 00:51:59,732 The strain of neglect 1315 00:51:59,732 --> 00:52:00,999 Is beginning to show 1316 00:52:00,999 --> 00:52:02,433 On even the best design 1317 00:52:02,433 --> 00:52:12,999 Of manmade structures. 1318 00:52:12,999 --> 00:52:14,799 everything that man designs 1319 00:52:14,799 --> 00:52:16,166 Carries within it, the seeds 1320 00:52:16,166 --> 00:52:18,466 Of its own destruction; 1321 00:52:18,466 --> 00:52:19,765 That includes bridges 1322 00:52:19,765 --> 00:52:21,899 And buildings. 1323 00:52:21,899 --> 00:52:22,932 The Brooklyn Bridge, 1324 00:52:22,932 --> 00:52:24,266 One of the most famous bridges 1325 00:52:24,266 --> 00:52:30,133 In the world for over 125 years. 1326 00:52:30,133 --> 00:52:30,866 The reason 1327 00:52:30,866 --> 00:52:32,799 Those bridges last so long 1328 00:52:32,799 --> 00:52:34,032 Is because engineers 1329 00:52:34,032 --> 00:52:35,266 Look after them. 1330 00:52:35,266 --> 00:52:36,566 They inspect them regularly, 1331 00:52:36,566 --> 00:52:37,566 They maintain them, 1332 00:52:37,566 --> 00:52:38,566 They paint them, 1333 00:52:38,566 --> 00:52:39,799 They replace pieces that need 1334 00:52:39,799 --> 00:52:41,466 To be replaced. 1335 00:52:41,466 --> 00:52:42,399 Without people, 1336 00:52:42,399 --> 00:52:43,699 Without engineers, 1337 00:52:43,699 --> 00:52:45,399 The deterioration process 1338 00:52:45,399 --> 00:52:50,799 Will accelerate dramatically. 1339 00:52:50,799 --> 00:52:52,066 the most vulnerable parts 1340 00:52:52,066 --> 00:52:53,600 Of a suspension bridge 1341 00:52:53,600 --> 00:52:55,266 Are the steel vertical hanger 1342 00:52:55,266 --> 00:53:00,866 Cables. 1343 00:53:00,932 --> 00:53:01,632 these have been tested 1344 00:53:01,632 --> 00:53:02,966 In the laboratory, 1345 00:53:02,966 --> 00:53:04,466 Unfortunately not on the bridge, 1346 00:53:04,466 --> 00:53:05,665 But what you see 1347 00:53:05,665 --> 00:53:08,133 Is a classic kind of a failure? 1348 00:53:08,133 --> 00:53:11,032 That occurs in these wires. 1349 00:53:11,032 --> 00:53:12,899 These are the individual wires, 1350 00:53:13,032 --> 00:53:13,433 All right? 1351 00:53:13,433 --> 00:53:15,266 That's an individual wire. 1352 00:53:15,266 --> 00:53:15,932 That probably has 1353 00:53:15,932 --> 00:53:16,732 A tensile strength 1354 00:53:16,732 --> 00:53:18,266 That's maybe 200,000 pounds 1355 00:53:18,266 --> 00:53:18,866 Per square inch. 1356 00:53:18,866 --> 00:53:19,832 That's a very high strength 1357 00:53:19,832 --> 00:53:21,399 Steel. 1358 00:53:21,399 --> 00:53:23,166 as strong as they are, 1359 00:53:23,166 --> 00:53:26,333 These cables have a fatal flaw: 1360 00:53:26,333 --> 00:53:32,032 It's the stuff they're made of. 1361 00:53:32,032 --> 00:53:32,899 steel is a mineral 1362 00:53:32,899 --> 00:53:34,433 That comes from the earth 1363 00:53:34,433 --> 00:53:36,433 That's mostly iron, 1364 00:53:36,433 --> 00:53:37,366 So it's probably 1365 00:53:37,366 --> 00:53:42,133 95, 98 percent iron. 1366 00:53:42,133 --> 00:53:43,366 exposed to moisture 1367 00:53:43,366 --> 00:53:44,999 In the environment, 1368 00:53:44,999 --> 00:53:46,399 Iron will start to revert 1369 00:53:46,399 --> 00:53:47,566 Back to the minerals 1370 00:53:47,566 --> 00:53:49,166 It came from. 1371 00:53:49,166 --> 00:53:53,099 Ashes to ashes, dust to dust. 1372 00:53:53,099 --> 00:53:55,066 it's going to go back home. 1373 00:53:55,066 --> 00:53:55,765 It came from the earth 1374 00:53:55,765 --> 00:53:58,133 As iron oxide of some form, 1375 00:53:58,133 --> 00:54:01,266 And it's going to go back. 1376 00:54:01,266 --> 00:54:02,832 this is the process we know 1377 00:54:02,832 --> 00:54:04,600 As corrosion, 1378 00:54:04,600 --> 00:54:06,133 And you see it wherever steel 1379 00:54:06,133 --> 00:54:09,233 Is exposed to moisture. 1380 00:54:09,233 --> 00:54:11,032 the enemy of steel 1381 00:54:11,032 --> 00:54:12,999 Is corrosion. 1382 00:54:12,999 --> 00:54:13,533 The problem 1383 00:54:13,533 --> 00:54:16,133 Is keeping the water out. 1384 00:54:16,133 --> 00:54:17,799 Part of that is maintenance. 1385 00:54:17,799 --> 00:54:19,166 If you don't maintain them, 1386 00:54:19,166 --> 00:54:23,732 You will get corrosion. 1387 00:54:23,732 --> 00:54:26,366 completed in 1883, 1388 00:54:26,366 --> 00:54:27,832 The Brooklyn bridge cost 1389 00:54:27,832 --> 00:54:31,832 $15 million to build. 1390 00:54:31,832 --> 00:54:33,632 Over the last two decades, 1391 00:54:33,632 --> 00:54:35,999 $3 billion have been spent 1392 00:54:35,999 --> 00:54:37,166 Maintaining it 1393 00:54:37,166 --> 00:54:38,233 And the other bridges 1394 00:54:38,233 --> 00:54:40,932 Over the east river. 1395 00:54:40,932 --> 00:54:43,032 In the time of humans, 1396 00:54:43,032 --> 00:54:43,999 The Brooklyn Bridge 1397 00:54:43,999 --> 00:54:45,732 Was continually maintained 1398 00:54:45,732 --> 00:54:47,266 And fully repainted, 1399 00:54:47,266 --> 00:54:49,966 Roughly, every dozen years. 1400 00:54:49,966 --> 00:54:51,199 While across the country 1401 00:54:51,199 --> 00:54:55,699 In San Francisco, 1402 00:54:55,699 --> 00:54:56,966 The golden gate bridge 1403 00:54:56,966 --> 00:54:59,032 Was protected at all times 1404 00:54:59,032 --> 00:55:00,466 By a vigilant brigade 1405 00:55:00,466 --> 00:55:02,632 Of 17 iron workers 1406 00:55:02,632 --> 00:55:07,600 And 38 painters. 1407 00:55:07,600 --> 00:55:08,732 what do they do all the time? 1408 00:55:08,732 --> 00:55:09,765 They will tell you, "We paint 1409 00:55:09,765 --> 00:55:12,866 This bridge continuously." 1410 00:55:12,866 --> 00:55:14,866 What happens when that stops? 1411 00:55:14,866 --> 00:55:15,600 I can tell you what happens 1412 00:55:15,600 --> 00:55:16,765 When that stops. 1413 00:55:16,765 --> 00:55:18,632 The cables begin to rust, 1414 00:55:18,632 --> 00:55:19,999 The paint peels off, 1415 00:55:19,999 --> 00:55:21,999 The wires begin to break, 1416 00:55:21,999 --> 00:55:23,699 And they'll come to a point 1417 00:55:23,699 --> 00:55:24,366 When the bridge 1418 00:55:24,366 --> 00:55:34,533 Is going to come down. 1419 00:55:34,533 --> 00:55:35,899 seventy-five years 1420 00:55:35,899 --> 00:55:38,600 After people. 1421 00:55:38,600 --> 00:55:41,166 Most of the 600 million cars 1422 00:55:41,166 --> 00:55:42,600 That once traveled the roads 1423 00:55:42,600 --> 00:55:44,233 Of the world 1424 00:55:44,233 --> 00:55:46,399 Are now just rusted remnants 1425 00:55:46,399 --> 00:55:52,566 Of the human past. 1426 00:55:52,566 --> 00:55:53,699 abandoned cars will behave 1427 00:55:53,699 --> 00:55:54,699 Differently depending 1428 00:55:54,699 --> 00:55:55,500 On the environment 1429 00:55:55,500 --> 00:55:57,166 That they're in. 1430 00:55:57,166 --> 00:55:58,433 A car left in the Mojave Desert, 1431 00:55:58,433 --> 00:55:59,032 For example, 1432 00:55:59,032 --> 00:56:01,433 Is going to last a long time. 1433 00:56:01,500 --> 00:56:02,433 A car abandoned 1434 00:56:02,433 --> 00:56:03,999 In my native Scotland 1435 00:56:03,999 --> 00:56:04,632 Is going to have 1436 00:56:04,632 --> 00:56:06,632 A very different fate. 1437 00:56:06,765 --> 00:56:07,433 Any cars 1438 00:56:07,433 --> 00:56:08,966 In a coastal environment 1439 00:56:08,966 --> 00:56:11,066 With salt in the atmosphere, 1440 00:56:11,066 --> 00:56:11,966 They might not last 1441 00:56:11,966 --> 00:56:16,765 More than 20, 30 years. 1442 00:56:16,765 --> 00:56:17,732 tires deflate 1443 00:56:17,732 --> 00:56:19,665 Within a few years, 1444 00:56:19,665 --> 00:56:20,433 Although the rubber 1445 00:56:20,433 --> 00:56:22,032 And synthetics they're made of 1446 00:56:22,032 --> 00:56:22,966 Will remain intact 1447 00:56:22,966 --> 00:56:25,932 For centuries. 1448 00:56:25,932 --> 00:56:28,433 Paint deteriorates quickly. 1449 00:56:28,433 --> 00:56:30,533 And once it flakes away, 1450 00:56:30,533 --> 00:56:32,665 Rust corrodes the car's body 1451 00:56:32,665 --> 00:56:34,466 At a rate of 5,000ths 1452 00:56:34,466 --> 00:56:37,466 Of an inch per year. 1453 00:56:37,466 --> 00:56:40,832 Seventy-five years after humans, 1454 00:56:40,832 --> 00:56:41,966 Most cars, 1455 00:56:41,966 --> 00:56:43,266 Even in the most forgiving 1456 00:56:43,266 --> 00:56:44,533 Of environments, 1457 00:56:44,533 --> 00:56:48,099 Will be reduced to skeletons. 1458 00:56:48,099 --> 00:56:50,932 After a century, the family car 1459 00:56:50,932 --> 00:56:53,166 Is a barely recognizable heap 1460 00:56:53,166 --> 00:57:06,999 Of metal. 1461 00:57:06,999 --> 00:57:09,665 It's now 100 years into a life 1462 00:57:09,665 --> 00:57:13,665 After people. 1463 00:57:13,665 --> 00:57:15,166 The Brooklyn Bridge, 1464 00:57:15,166 --> 00:57:15,932 Which had stood? 1465 00:57:15,932 --> 00:57:19,632 For over 125 years with people, 1466 00:57:19,632 --> 00:57:21,632 Can't survive even a century 1467 00:57:21,632 --> 00:57:24,333 Without them. 1468 00:57:24,333 --> 00:57:26,133 As the cables fail, 1469 00:57:26,133 --> 00:57:27,866 The deck and railings begin 1470 00:57:27,866 --> 00:57:35,233 To warp and sway. 1471 00:57:35,233 --> 00:57:38,732 The deck pulls free, 1472 00:57:38,732 --> 00:57:40,433 And the roadway spills 1473 00:57:40,433 --> 00:57:49,665 Into the east river. 1474 00:57:49,665 --> 00:57:51,732 as an engineer, 1475 00:57:51,732 --> 00:57:53,665 It's very sad to contemplate 1476 00:57:53,665 --> 00:57:55,333 That this beautiful iconic 1477 00:57:55,333 --> 00:57:56,999 Structure has got an end 1478 00:57:56,999 --> 00:57:58,366 To its life. 1479 00:57:58,366 --> 00:57:59,999 But without maintenance, 1480 00:57:59,999 --> 00:58:00,999 An end to its life 1481 00:58:00,999 --> 00:58:07,166 It certainly has. 1482 00:58:07,166 --> 00:58:10,299 how exactly do bridges fail? 1483 00:58:10,299 --> 00:58:12,166 Once corrosion starts, 1484 00:58:12,166 --> 00:58:15,566 The wires begin to crack. 1485 00:58:15,566 --> 00:58:16,099 and the wire 1486 00:58:16,099 --> 00:58:16,665 Doesn't have to have 1487 00:58:16,665 --> 00:58:17,500 A very big crack 1488 00:58:17,500 --> 00:58:18,699 Before it breaks. 1489 00:58:18,699 --> 00:58:20,366 Maybe a third 1490 00:58:20,366 --> 00:58:22,433 Of the way through. 1491 00:58:22,500 --> 00:58:23,899 You may wonder what happens 1492 00:58:23,899 --> 00:58:24,665 When they fail. 1493 00:58:24,665 --> 00:58:25,500 How do they fail? 1494 00:58:25,500 --> 00:58:26,333 Do they just break? 1495 00:58:26,333 --> 00:58:27,199 And what do they do? 1496 00:58:27,199 --> 00:58:27,799 And the answer 1497 00:58:27,799 --> 00:58:30,533 Is they tend to shred and fail, 1498 00:58:30,665 --> 00:58:31,665 With individual strands 1499 00:58:31,665 --> 00:58:32,366 Starting to fail 1500 00:58:32,366 --> 00:58:34,133 And then, kind of, cascading, 1501 00:58:34,133 --> 00:58:35,832 And a whole series of wires 1502 00:58:35,832 --> 00:58:39,799 Then begin to break. 1503 00:58:39,799 --> 00:58:40,832 a suspension bridge 1504 00:58:40,832 --> 00:58:42,866 Like the golden gate can survive 1505 00:58:42,866 --> 00:58:44,466 The weakening of one 1506 00:58:44,466 --> 00:58:46,466 Of its vertical cables. 1507 00:58:46,466 --> 00:58:47,765 But once two or three 1508 00:58:47,765 --> 00:58:49,166 Start to go, 1509 00:58:49,166 --> 00:58:52,600 The whole bridge is in jeopardy. 1510 00:58:52,600 --> 00:58:54,665 Twisted steel crashes 1511 00:58:54,665 --> 00:58:58,999 Into the waters below. 1512 00:58:58,999 --> 00:59:01,266 it's going to be gone. 1513 00:59:01,266 --> 00:59:02,500 Two hundred years? 1514 00:59:02,500 --> 00:59:05,299 I doubt it will last 200 years. 1515 00:59:05,299 --> 00:59:06,765 The bridge is going to be 1516 00:59:06,765 --> 00:59:08,133 In the drink. 1517 00:59:08,133 --> 00:59:09,966 [music] 1518 00:59:09,966 --> 00:59:10,533 if some 1519 00:59:10,533 --> 00:59:11,832 Of our largest structures 1520 00:59:11,832 --> 00:59:13,099 Have already failed 1521 00:59:13,099 --> 00:59:16,133 After 100 years, 1522 00:59:16,133 --> 00:59:17,566 Can there be any hope 1523 00:59:17,566 --> 00:59:18,600 That our civilization 1524 00:59:18,600 --> 00:59:20,233 Will leave a permanent mark 1525 00:59:20,233 --> 00:59:24,533 After we're gone? 1526 00:59:24,533 --> 00:59:26,099 What will remain of the records? 1527 00:59:26,099 --> 00:59:28,233 Of our history and culture 1528 00:59:28,233 --> 00:59:33,133 A hundred years after people? 1529 00:59:33,133 --> 00:59:34,500 our vaults contain 1530 00:59:34,500 --> 00:59:37,299 Our most precious materials, 1531 00:59:37,299 --> 00:59:38,299 And their biggest enemies 1532 00:59:38,299 --> 00:59:43,765 Are temperature and humidity. 1533 00:59:43,765 --> 00:59:44,399 As long 1534 00:59:44,399 --> 00:59:46,399 As their long-term storage 1535 00:59:46,399 --> 00:59:47,533 Is kept at these 1536 00:59:47,533 --> 00:59:50,566 Very controlled settings, 1537 00:59:50,566 --> 00:59:51,632 We feel assured 1538 00:59:51,632 --> 00:59:52,699 That the materials 1539 00:59:52,699 --> 00:59:59,066 Will be lasting a long time. 1540 00:59:59,066 --> 01:00:00,233 stored 1541 01:00:00,233 --> 01:00:01,799 Under ideal conditions, 1542 01:00:01,799 --> 01:00:03,866 Paper and film both have 1543 01:00:03,866 --> 01:00:05,333 An estimated shelf life 1544 01:00:05,333 --> 01:00:09,500 Of 200 to 300 years. 1545 01:00:09,500 --> 01:00:10,999 But expose them to the rigors 1546 01:00:10,999 --> 01:00:13,366 Of an uncontrolled environment 1547 01:00:13,366 --> 01:00:15,233 And that lifespan is cut 1548 01:00:15,233 --> 01:00:19,166 At least in half. 1549 01:00:19,233 --> 01:00:23,732 if all the power went off, 1550 01:00:23,732 --> 01:00:24,932 Probably within a week, 1551 01:00:24,932 --> 01:00:27,199 We'd see very big spikes 1552 01:00:27,333 --> 01:00:32,266 In the temperature and humidity. 1553 01:00:32,266 --> 01:00:35,433 in this hostile environment, 1554 01:00:35,433 --> 01:00:37,199 Cellulose acetate, 1555 01:00:37,199 --> 01:00:38,433 The most common material 1556 01:00:38,433 --> 01:00:40,566 Used for films and photographs 1557 01:00:40,566 --> 01:00:43,732 Throughout the 20th century 1558 01:00:43,732 --> 01:00:47,765 Begins to bubble and warp. 1559 01:00:47,765 --> 01:00:49,866 All of that culture and history, 1560 01:00:49,866 --> 01:00:51,832 From the landings on d-day 1561 01:00:51,832 --> 01:00:53,366 To Hollywood films 1562 01:00:53,366 --> 01:00:54,533 And even your cherished 1563 01:00:54,533 --> 01:00:56,533 Home movies and photographs, 1564 01:00:56,533 --> 01:00:58,199 Won't last a century 1565 01:00:58,199 --> 01:01:01,765 Without the care of humans. 1566 01:01:01,765 --> 01:01:04,199 so, those precious images, 1567 01:01:04,199 --> 01:01:06,133 Given time, 1568 01:01:06,133 --> 01:01:09,333 Are going to end up like this. 1569 01:01:09,333 --> 01:01:10,533 All of these are examples 1570 01:01:10,533 --> 01:01:13,166 Of various stages in the decay 1571 01:01:13,166 --> 01:01:16,665 Of cellulose acetate-based film 1572 01:01:16,665 --> 01:01:18,166 Exposed to very high amounts 1573 01:01:18,166 --> 01:01:19,999 Of humidity. 1574 01:01:19,999 --> 01:01:20,966 Essentially, 1575 01:01:20,966 --> 01:01:27,533 These materials are finished. 1576 01:01:27,533 --> 01:01:29,166 in libraries, 1577 01:01:29,166 --> 01:01:30,600 The great repositories 1578 01:01:30,600 --> 01:01:32,732 Of our collective knowledge, 1579 01:01:32,732 --> 01:01:33,799 The damage comes 1580 01:01:33,799 --> 01:01:39,832 From microscopic invaders. 1581 01:01:39,832 --> 01:01:41,832 Although we can't see them, 1582 01:01:41,832 --> 01:01:42,932 Mold spores 1583 01:01:42,932 --> 01:01:44,266 Are on all the surfaces 1584 01:01:44,266 --> 01:01:46,932 Around us, lying dormant, 1585 01:01:46,932 --> 01:01:48,266 Biding their time 1586 01:01:48,266 --> 01:01:49,699 For the right conditions 1587 01:01:49,699 --> 01:01:54,433 To strike. 1588 01:01:54,433 --> 01:01:55,732 High humidity 1589 01:01:55,732 --> 01:01:59,466 Creates the right conditions. 1590 01:01:59,466 --> 01:02:00,299 and so, 1591 01:02:00,299 --> 01:02:02,266 The situation is set up 1592 01:02:02,266 --> 01:02:11,399 For the mold to really boom. 1593 01:02:11,399 --> 01:02:12,466 some books and documents 1594 01:02:12,466 --> 01:02:16,133 Will avoid this fate. 1595 01:02:16,133 --> 01:02:17,433 The Dead Sea scrolls 1596 01:02:17,433 --> 01:02:19,832 Survived 2,000 years in caves 1597 01:02:19,832 --> 01:02:21,600 In the Judean desert, 1598 01:02:21,600 --> 01:02:22,799 Owing their longevity 1599 01:02:22,799 --> 01:02:24,233 To the arid climate 1600 01:02:24,233 --> 01:02:28,632 And lack of damaging sunlight. 1601 01:02:28,632 --> 01:02:32,466 But these are rare exceptions. 1602 01:02:32,466 --> 01:02:33,032 so without 1603 01:02:33,032 --> 01:02:34,600 Human intervention, 1604 01:02:34,600 --> 01:02:36,099 A book like this might last, 1605 01:02:36,099 --> 01:02:42,233 At best, another hundred years. 1606 01:02:42,233 --> 01:02:48,933 [music] 1607 01:02:48,933 --> 01:02:50,499 even our digital media 1608 01:02:50,499 --> 01:02:53,866 Won't last forever. 1609 01:02:53,866 --> 01:02:55,066 Estimates for the lifespan 1610 01:02:55,066 --> 01:02:57,766 Of cads and DVDs range 1611 01:02:57,766 --> 01:02:59,266 From a few decades 1612 01:02:59,266 --> 01:03:00,632 To a few centuries 1613 01:03:00,632 --> 01:03:04,599 Under ideal conditions. 1614 01:03:04,599 --> 01:03:04,966 we know 1615 01:03:04,966 --> 01:03:06,166 About the ancient Egyptians 1616 01:03:06,166 --> 01:03:08,233 Because what they left behind 1617 01:03:08,233 --> 01:03:09,699 Was engraved in stones. 1618 01:03:09,699 --> 01:03:14,033 [music] 1619 01:03:14,099 --> 01:03:16,599 Our form of capturing knowledge, 1620 01:03:16,599 --> 01:03:18,099 Information, our history, 1621 01:03:18,099 --> 01:03:20,199 Our advancement is typically 1622 01:03:20,199 --> 01:03:21,465 Either in a computerized form, 1623 01:03:21,465 --> 01:03:23,899 In a cod, or in a printed paper 1624 01:03:23,899 --> 01:03:25,300 Like this. 1625 01:03:25,432 --> 01:03:26,532 What we have here is something 1626 01:03:26,532 --> 01:03:28,133 That will degrade over time. 1627 01:03:28,133 --> 01:03:29,666 It will not last 1628 01:03:29,666 --> 01:03:30,799 For thousands of years 1629 01:03:30,799 --> 01:03:31,432 Like what 1630 01:03:31,432 --> 01:03:32,465 The ancient Egyptians 1631 01:03:32,465 --> 01:03:34,799 Left behind. 1632 01:03:34,799 --> 01:03:37,632 it seems pretty ironic 1633 01:03:37,632 --> 01:03:40,899 That with all of our advances, 1634 01:03:40,899 --> 01:03:42,933 We still have not come up 1635 01:03:42,933 --> 01:03:44,432 With anything as durable 1636 01:03:44,432 --> 01:03:49,532 As clay tablets and stone tools. 1637 01:03:49,532 --> 01:03:57,300 [music] 1638 01:03:57,300 --> 01:04:01,565 150 years after humans, 1639 01:04:01,565 --> 01:04:02,333 The subways 1640 01:04:02,333 --> 01:04:03,699 That had started to flood 1641 01:04:03,699 --> 01:04:06,832 In the first 36 hours 1642 01:04:06,832 --> 01:04:07,632 Are now flowing 1643 01:04:07,632 --> 01:04:11,333 Subterranean streams. 1644 01:04:11,333 --> 01:04:12,732 The beams and archways 1645 01:04:12,732 --> 01:04:13,966 That holds up the roofs 1646 01:04:13,966 --> 01:04:15,465 Of these tunnels 1647 01:04:15,465 --> 01:04:19,166 Are on the verge of collapse. 1648 01:04:19,166 --> 01:04:19,866 now, these tunnels 1649 01:04:19,866 --> 01:04:21,899 Are not far below street level. 1650 01:04:21,899 --> 01:04:23,933 These columns are supporting 1651 01:04:23,933 --> 01:04:25,699 Not just the roof of the tunnel, 1652 01:04:25,699 --> 01:04:27,532 But the street above. 1653 01:04:27,532 --> 01:04:28,999 And in time that these tunnels 1654 01:04:28,999 --> 01:04:30,266 Are inundated, 1655 01:04:30,266 --> 01:04:31,400 Flooded with water, 1656 01:04:31,400 --> 01:04:32,400 Corrosion will start 1657 01:04:32,400 --> 01:04:33,966 To take hold and we'll start 1658 01:04:33,966 --> 01:04:37,333 To see collapses. 1659 01:04:37,333 --> 01:04:38,333 the tunnels echo 1660 01:04:38,333 --> 01:04:39,166 With the sound 1661 01:04:39,166 --> 01:04:42,899 Of cracking steel and cement 1662 01:04:42,899 --> 01:04:47,899 As the streets above 1663 01:04:47,899 --> 01:04:50,532 Are sucked into the underground. 1664 01:04:50,532 --> 01:04:58,699 [music] 1665 01:04:58,699 --> 01:05:01,532 Above ground, life in the city 1666 01:05:01,532 --> 01:05:06,233 Is once again bustling. 1667 01:05:06,233 --> 01:05:08,099 Vines have grown up the sides 1668 01:05:08,099 --> 01:05:10,866 Of abandoned skyscrapers, 1669 01:05:10,866 --> 01:05:13,066 Adapting to feed off rainwater 1670 01:05:13,066 --> 01:05:15,233 That pools in crevices 1671 01:05:15,233 --> 01:05:19,699 And on ledges. 1672 01:05:19,699 --> 01:05:21,333 these vines all start up. 1673 01:05:21,333 --> 01:05:22,233 And the vines 1674 01:05:22,233 --> 01:05:23,400 Have little branches. 1675 01:05:23,400 --> 01:05:23,933 It'd be nice 1676 01:05:23,933 --> 01:05:25,166 If they produce a fruit 1677 01:05:25,166 --> 01:05:27,465 Or something that was edible. 1678 01:05:27,532 --> 01:05:28,400 You got to have a plant 1679 01:05:28,400 --> 01:05:30,300 With some fruit or, you know, 1680 01:05:30,300 --> 01:05:31,999 Some source of energy 1681 01:05:31,999 --> 01:05:33,933 For animals. 1682 01:05:34,066 --> 01:05:34,632 And then you would get 1683 01:05:34,632 --> 01:05:37,666 This vertical ecosystem 1684 01:05:37,666 --> 01:05:38,933 Out there, and you would get 1685 01:05:38,933 --> 01:05:41,199 Birds nesting in there. 1686 01:05:41,199 --> 01:05:41,766 You get things 1687 01:05:41,766 --> 01:05:42,866 Hunting in through there. 1688 01:05:42,866 --> 01:05:44,666 You could have snakes there. 1689 01:05:44,666 --> 01:05:45,133 You could have 1690 01:05:45,133 --> 01:05:53,666 All kinds of things. 1691 01:05:53,666 --> 01:05:54,532 as insects 1692 01:05:54,532 --> 01:05:55,465 And smaller animals 1693 01:05:55,465 --> 01:06:00,300 Get established, 1694 01:06:00,300 --> 01:06:05,366 Cats move in. 1695 01:06:05,366 --> 01:06:06,066 and there's some 1696 01:06:06,066 --> 01:06:07,400 Interesting examples of that 1697 01:06:07,400 --> 01:06:09,565 Around the world. 1698 01:06:09,565 --> 01:06:10,799 If you go to the coliseum-- 1699 01:06:10,799 --> 01:06:11,699 You just look in it-- 1700 01:06:11,699 --> 01:06:14,799 It's just loaded with cats. 1701 01:06:14,799 --> 01:06:15,732 And the old tombs 1702 01:06:15,732 --> 01:06:17,400 And old catacombs and so on 1703 01:06:17,400 --> 01:06:18,766 Get loaded with cats 1704 01:06:18,766 --> 01:06:20,166 That uses this as a living space 1705 01:06:20,166 --> 01:06:20,866 From which, then, 1706 01:06:20,866 --> 01:06:25,766 They radiate out during the day. 1707 01:06:25,766 --> 01:06:26,866 these felines 1708 01:06:26,866 --> 01:06:27,832 Are the descendants 1709 01:06:27,832 --> 01:06:30,599 Of our former house cats. 1710 01:06:30,599 --> 01:06:31,699 Immediately after people 1711 01:06:31,699 --> 01:06:33,632 Were gone, they replaced 1712 01:06:33,632 --> 01:06:35,599 Their human-supplied diets 1713 01:06:35,599 --> 01:06:38,899 With field mice and small birds. 1714 01:06:38,899 --> 01:06:40,266 Hunting out in the open 1715 01:06:40,266 --> 01:06:42,933 Was hard work. 1716 01:06:42,933 --> 01:06:44,333 But up here, 1717 01:06:44,333 --> 01:06:48,233 The pickings are easy. 1718 01:06:48,233 --> 01:06:49,532 Now, they live 1719 01:06:49,532 --> 01:06:50,766 Their whole lives 1720 01:06:50,766 --> 01:06:52,866 High above the city, 1721 01:06:52,866 --> 01:06:54,199 Finding all that they need 1722 01:06:54,199 --> 01:06:56,532 To survive without ever having 1723 01:06:56,532 --> 01:06:59,266 To touch the ground. 1724 01:06:59,266 --> 01:07:00,366 They are the kings 1725 01:07:00,366 --> 01:07:01,966 Of the new high altitude 1726 01:07:01,966 --> 01:07:03,266 Food chain, 1727 01:07:03,266 --> 01:07:05,066 With million-dollar views 1728 01:07:05,066 --> 01:07:05,999 Of a bizarrely 1729 01:07:05,999 --> 01:07:15,799 Altered cityscape. 1730 01:07:15,799 --> 01:07:17,266 I could picture new York city 1731 01:07:17,266 --> 01:07:19,166 With all the buildings 1732 01:07:19,166 --> 01:07:21,933 Covered with vines, you know? 1733 01:07:21,933 --> 01:07:25,333 Hawks sailing around. 1734 01:07:25,333 --> 01:07:26,632 It'd be lovely. 1735 01:07:26,632 --> 01:07:28,465 It would be absolutely lovely. 1736 01:07:28,465 --> 01:07:31,766 [music] 1737 01:07:31,766 --> 01:07:33,233 for cats, 1738 01:07:33,233 --> 01:07:35,266 Life in this new environment 1739 01:07:35,266 --> 01:07:36,532 Could eventually lead 1740 01:07:36,532 --> 01:07:41,199 To some strange adaptations. 1741 01:07:41,199 --> 01:07:42,199 I suppose, if you wanted 1742 01:07:42,199 --> 01:07:43,300 To be really imaginative 1743 01:07:43,300 --> 01:07:45,766 About it, you could say that, 1744 01:07:45,766 --> 01:07:46,866 Eventually, they could be 1745 01:07:46,866 --> 01:07:48,666 Like flying squirrels and so on. 1746 01:07:48,666 --> 01:07:52,465 They could glide from places. 1747 01:07:52,465 --> 01:07:55,465 The possibility is always there 1748 01:07:55,465 --> 01:07:59,166 For some imaginative responses 1749 01:07:59,166 --> 01:08:05,532 To this unusual environment. 1750 01:08:05,532 --> 01:08:06,565 while some cats 1751 01:08:06,565 --> 01:08:11,066 Have made a great leap forward, 1752 01:08:11,066 --> 01:08:13,166 Many dogs have reverted 1753 01:08:13,166 --> 01:08:16,999 To the ways of their ancestors. 1754 01:08:16,999 --> 01:08:19,099 Some that have interbred 1755 01:08:19,099 --> 01:08:22,400 With wolves now fall in packs 1756 01:08:22,400 --> 01:08:25,532 To bring down larger prey. 1757 01:08:25,532 --> 01:08:33,933 [music] 1758 01:08:33,999 --> 01:08:35,732 I think our dogs, 1759 01:08:35,732 --> 01:08:37,333 As placid as they may seem 1760 01:08:37,333 --> 01:08:38,499 When they're in our homes 1761 01:08:38,499 --> 01:08:40,532 Lying on the living room floor, 1762 01:08:40,666 --> 01:08:42,866 Still posses the instinct 1763 01:08:42,866 --> 01:08:44,233 To survive, 1764 01:08:44,233 --> 01:08:45,999 Enough that they would be able 1765 01:08:45,999 --> 01:08:48,432 To do whatever it took 1766 01:08:48,432 --> 01:08:49,400 In bringing down prey 1767 01:08:49,400 --> 01:08:51,766 In order to live. 1768 01:08:51,766 --> 01:09:03,933 [music] 1769 01:09:03,933 --> 01:09:10,499 150 years after people, 1770 01:09:10,499 --> 01:09:11,899 The oceans are teeming 1771 01:09:11,899 --> 01:09:16,366 With life. 1772 01:09:16,366 --> 01:09:17,766 The creatures of the sea 1773 01:09:17,766 --> 01:09:18,599 Have welcomed 1774 01:09:18,599 --> 01:09:22,699 The disappearance of mankind. 1775 01:09:22,699 --> 01:09:23,599 historically, 1776 01:09:23,599 --> 01:09:24,400 We've treated the oceans 1777 01:09:24,400 --> 01:09:26,166 In two strange ways 1778 01:09:26,166 --> 01:09:27,933 At the same time: 1779 01:09:27,933 --> 01:09:31,933 A pantry and a toilet. 1780 01:09:31,999 --> 01:09:33,933 And over time, 1781 01:09:33,933 --> 01:09:36,799 Our ability to damage the ocean 1782 01:09:36,799 --> 01:09:41,966 Has grown and grown and grown. 1783 01:09:42,099 --> 01:09:43,832 with humans no longer fishing 1784 01:09:43,832 --> 01:09:45,666 And polluting the sea, 1785 01:09:45,666 --> 01:09:46,832 The path was cleared 1786 01:09:46,832 --> 01:09:49,366 For this astonishing recovery. 1787 01:09:49,366 --> 01:09:52,599 It has happened before. 1788 01:09:52,599 --> 01:09:54,300 During World War II, 1789 01:09:54,300 --> 01:09:55,966 Allied fishing trawlers 1790 01:09:55,966 --> 01:09:58,532 Avoided the north Atlantic, 1791 01:09:58,532 --> 01:10:00,099 And populations of fish there 1792 01:10:00,099 --> 01:10:04,799 Skyrocketed. 1793 01:10:04,799 --> 01:10:06,599 in here, the basic biology 1794 01:10:06,599 --> 01:10:07,666 Of these kinds of animals 1795 01:10:07,666 --> 01:10:08,799 Is working in our favor 1796 01:10:08,799 --> 01:10:10,033 Because animals 1797 01:10:10,033 --> 01:10:10,899 Like this sunfish 1798 01:10:10,899 --> 01:10:11,465 Can produce millions 1799 01:10:11,465 --> 01:10:14,066 Of offspring in a year, 1800 01:10:14,066 --> 01:10:14,899 Much more 1801 01:10:14,899 --> 01:10:15,832 Than an equivalent-sized 1802 01:10:15,832 --> 01:10:18,599 Terrestrial animal like a cow. 1803 01:10:18,599 --> 01:10:19,400 And because of that 1804 01:10:19,400 --> 01:10:20,632 Prodigious potential 1805 01:10:20,632 --> 01:10:22,233 To reproduce, 1806 01:10:22,233 --> 01:10:23,832 The oceans could come back 1807 01:10:23,832 --> 01:10:25,133 Pretty quickly 1808 01:10:25,133 --> 01:10:27,099 If the human population 1809 01:10:27,099 --> 01:10:33,432 Were suddenly to disappear. 1810 01:10:33,432 --> 01:10:34,599 research has shown 1811 01:10:34,599 --> 01:10:36,333 That in the 18th century, 1812 01:10:36,333 --> 01:10:37,300 Before the havoc 1813 01:10:37,300 --> 01:10:38,799 Caused by humans, 1814 01:10:38,799 --> 01:10:39,899 The oceans were capable 1815 01:10:39,899 --> 01:10:40,699 Of sustaining 1816 01:10:40,699 --> 01:10:45,133 Massive amounts of life. 1817 01:10:45,133 --> 01:10:45,999 so many whales 1818 01:10:45,999 --> 01:10:48,966 That they stink up the air; 1819 01:10:48,966 --> 01:10:50,199 So many tunas 1820 01:10:50,199 --> 01:10:52,066 That they froth the ocean; 1821 01:10:52,066 --> 01:10:52,766 So many turtles 1822 01:10:52,766 --> 01:10:53,499 That you could walk 1823 01:10:53,499 --> 01:10:55,933 Across the sea on their backs. 1824 01:10:55,933 --> 01:10:58,066 So, if people were to vanish 1825 01:10:58,066 --> 01:10:59,266 Off the face of the earth, 1826 01:10:59,266 --> 01:11:00,999 Then that's the kind of ocean 1827 01:11:00,999 --> 01:11:06,999 It could be. 1828 01:11:06,999 --> 01:11:10,166 [music] 1829 01:11:10,166 --> 01:11:11,565 seagulls are also 1830 01:11:11,565 --> 01:11:13,532 Flourishing, but it has been 1831 01:11:13,532 --> 01:11:15,999 A treacherous flight. 1832 01:11:15,999 --> 01:11:17,166 The abundance of food 1833 01:11:17,166 --> 01:11:17,832 From humans 1834 01:11:17,832 --> 01:11:19,432 Had allowed gull populations 1835 01:11:19,432 --> 01:11:21,465 To explode beyond what nature 1836 01:11:21,465 --> 01:11:25,766 Could normally support. 1837 01:11:25,766 --> 01:11:26,266 we humans 1838 01:11:26,266 --> 01:11:28,199 Are pretty messy species. 1839 01:11:28,199 --> 01:11:29,999 And for a very long time, 1840 01:11:29,999 --> 01:11:31,866 We had open landfill dumps 1841 01:11:31,866 --> 01:11:32,866 Where, as far 1842 01:11:32,866 --> 01:11:33,699 As we were concerned, 1843 01:11:33,699 --> 01:11:34,199 All the stuff 1844 01:11:34,199 --> 01:11:35,499 That wasn't fit to eat 1845 01:11:35,499 --> 01:11:36,832 Was just thrown out. 1846 01:11:36,832 --> 01:11:37,899 But from the gulls' 1847 01:11:37,899 --> 01:11:38,565 Point of view, 1848 01:11:38,565 --> 01:11:39,300 This was an amazing 1849 01:11:39,300 --> 01:11:41,033 Free lunch counter. 1850 01:11:41,099 --> 01:11:42,300 So, you had a lot of birds 1851 01:11:42,300 --> 01:11:42,799 That probably 1852 01:11:42,799 --> 01:11:43,699 Wouldn't have made it through 1853 01:11:43,699 --> 01:11:44,499 Their first winter 1854 01:11:44,499 --> 01:11:45,099 If they've had to feed 1855 01:11:45,099 --> 01:11:46,300 For themselves. 1856 01:11:46,300 --> 01:11:46,933 Suddenly, they had 1857 01:11:46,933 --> 01:11:47,866 All these free food 1858 01:11:47,866 --> 01:11:50,266 Available to them. 1859 01:11:50,400 --> 01:11:51,033 An immediate consequence 1860 01:11:51,033 --> 01:11:52,699 Of a world without people 1861 01:11:52,699 --> 01:11:54,066 Would be some very hungry gulls 1862 01:11:54,066 --> 01:11:55,899 Who would be very voraciously? 1863 01:11:55,899 --> 01:12:00,366 Looking for other things to eat. 1864 01:12:00,366 --> 01:12:03,799 after an initial die-off, 1865 01:12:03,799 --> 01:12:04,933 The remaining gulls 1866 01:12:04,933 --> 01:12:05,933 Took advantage 1867 01:12:05,933 --> 01:12:07,832 Of the recovering oceans, 1868 01:12:07,832 --> 01:12:09,400 Where plentiful schools of fish 1869 01:12:09,400 --> 01:12:11,133 Erased any memories 1870 01:12:11,133 --> 01:12:13,366 Of the human-manufactured feasts 1871 01:12:13,366 --> 01:12:21,400 They used to enjoy. 1872 01:12:21,400 --> 01:12:25,133 Two hundred years after people, 1873 01:12:25,133 --> 01:12:27,966 From New York to Chicago, 1874 01:12:27,966 --> 01:12:30,400 Seattle and Paris, 1875 01:12:30,400 --> 01:12:32,333 Our iron and steel icons 1876 01:12:32,333 --> 01:12:37,832 Are on the verge of collapse. 1877 01:12:37,832 --> 01:12:39,099 While it has outlived 1878 01:12:39,099 --> 01:12:41,432 Our great suspension bridges, 1879 01:12:41,432 --> 01:12:42,632 The Eiffel tower 1880 01:12:42,632 --> 01:12:44,799 Is not invincible. 1881 01:12:44,799 --> 01:12:46,465 In the time of humans, 1882 01:12:46,465 --> 01:12:47,832 Its iron superstructure 1883 01:12:47,832 --> 01:12:48,565 Was painted 1884 01:12:48,565 --> 01:12:50,300 Once every seven years 1885 01:12:50,300 --> 01:12:54,766 To protect it from corrosion. 1886 01:12:54,766 --> 01:12:57,066 In both age and structure, 1887 01:12:57,066 --> 01:12:58,166 The Eiffel tower 1888 01:12:58,166 --> 01:12:59,400 Has a lot in common 1889 01:12:59,400 --> 01:13:00,766 With the 300-foot high 1890 01:13:00,766 --> 01:13:02,732 Kinsman railroad viaduct 1891 01:13:02,732 --> 01:13:04,666 In Pennsylvania. 1892 01:13:04,666 --> 01:13:05,166 was a bridge 1893 01:13:05,166 --> 01:13:05,732 That was wrought iron 1894 01:13:05,732 --> 01:13:06,866 Originally. 1895 01:13:06,866 --> 01:13:07,899 It was reconstructed 1896 01:13:07,899 --> 01:13:08,832 About the turn of the century 1897 01:13:08,832 --> 01:13:11,166 In steel. 1898 01:13:11,233 --> 01:13:12,532 And what happens here of course 1899 01:13:12,532 --> 01:13:14,933 Is that unless it's maintained, 1900 01:13:14,933 --> 01:13:16,199 Corrosion occurs. 1901 01:13:16,199 --> 01:13:16,832 And what happens 1902 01:13:16,832 --> 01:13:18,732 With the corrosion? 1903 01:13:18,866 --> 01:13:22,366 The connection points freeze up. 1904 01:13:22,366 --> 01:13:25,133 They are not allowed to move. 1905 01:13:25,133 --> 01:13:25,899 And here are some pieces 1906 01:13:25,899 --> 01:13:27,066 From that viaduct. 1907 01:13:27,066 --> 01:13:27,699 You can see 1908 01:13:27,699 --> 01:13:28,432 That there's corrosion 1909 01:13:28,432 --> 01:13:29,866 All over the place. 1910 01:13:29,866 --> 01:13:33,933 That's no longer steel. 1911 01:13:33,933 --> 01:13:34,565 a structure 1912 01:13:34,565 --> 01:13:36,400 With frozen connection points 1913 01:13:36,400 --> 01:13:37,999 Can't absorb the stress 1914 01:13:37,999 --> 01:13:40,799 Of high winds. 1915 01:13:40,799 --> 01:13:41,832 eventually, 1916 01:13:41,832 --> 01:13:43,400 In this strong wind storm, 1917 01:13:43,400 --> 01:13:49,532 It literally fell over. 1918 01:13:49,532 --> 01:13:51,300 Section by section, 1919 01:13:51,300 --> 01:13:52,532 Piece by piece, 1920 01:13:52,532 --> 01:13:54,966 It fell over into the valley 1921 01:13:54,966 --> 01:13:56,666 Where it had spanned the valley 1922 01:13:56,666 --> 01:14:02,333 For over a hundred years. 1923 01:14:02,333 --> 01:14:06,199 Just not maintained. 1924 01:14:06,199 --> 01:14:07,499 You can think of many structures 1925 01:14:07,499 --> 01:14:08,199 That is coming 1926 01:14:08,199 --> 01:14:09,233 From that same era 1927 01:14:09,233 --> 01:14:10,199 Like the Eiffel tower, 1928 01:14:10,199 --> 01:14:11,732 Its iconic structure. 1929 01:14:11,732 --> 01:14:12,532 That doesn't shield it 1930 01:14:12,532 --> 01:14:14,033 From the fact that's it 1931 01:14:14,033 --> 01:14:17,666 In a corrosive environment. 1932 01:14:17,666 --> 01:14:19,266 And so in time 1933 01:14:19,266 --> 01:14:20,899 If you do not do anything 1934 01:14:20,899 --> 01:14:22,099 For that structure, 1935 01:14:22,099 --> 01:14:26,266 It will fail. 1936 01:14:26,266 --> 01:14:51,966 And it will come down. 1937 01:14:51,966 --> 01:14:53,333 the time between one 1938 01:14:53,333 --> 01:14:56,333 And 300 years after people 1939 01:14:56,333 --> 01:14:57,766 Will likely be the era? 1940 01:14:57,766 --> 01:14:59,066 Of the great collapses 1941 01:14:59,066 --> 01:15:01,966 Worldwide. 1942 01:15:01,966 --> 01:15:03,300 In Seattle, 1943 01:15:03,300 --> 01:15:04,666 The iconic space needle 1944 01:15:04,666 --> 01:15:05,832 Was designed to sway 1945 01:15:05,832 --> 01:15:07,999 One inch for every 10 miles 1946 01:15:07,999 --> 01:15:09,666 Per hour of wind, 1947 01:15:09,666 --> 01:15:10,666 But with its steel 1948 01:15:10,666 --> 01:15:12,565 Weakened by corrosion, 1949 01:15:12,565 --> 01:15:13,565 It takes little more 1950 01:15:13,565 --> 01:15:14,933 Than a strong breeze 1951 01:15:14,933 --> 01:15:15,832 For the symbol 1952 01:15:15,832 --> 01:15:18,465 Of the 1962 world's fair 1953 01:15:18,465 --> 01:15:38,999 To crash down from the skyline. 1954 01:15:38,999 --> 01:15:40,732 When humans disappeared, 1955 01:15:40,732 --> 01:15:41,999 Sea levels were already 1956 01:15:41,999 --> 01:15:45,732 On the rise. 1957 01:15:45,732 --> 01:15:46,699 In Manhattan, 1958 01:15:46,699 --> 01:15:48,033 Over the centuries, 1959 01:15:48,033 --> 01:15:49,499 Saturated soil 1960 01:15:49,499 --> 01:15:50,632 Around the empire state 1961 01:15:50,632 --> 01:15:52,766 Building's foundation pilings 1962 01:15:52,766 --> 01:15:53,933 Have allowed the building 1963 01:15:53,933 --> 01:15:55,099 To lean. 1964 01:15:55,166 --> 01:15:56,666 once a building strays 1965 01:15:56,666 --> 01:15:57,666 From the vertical, 1966 01:15:57,666 --> 01:15:58,499 Then gravity forces 1967 01:15:58,499 --> 01:16:00,099 Are also acting 1968 01:16:00,099 --> 01:16:01,432 Against the structure, 1969 01:16:01,432 --> 01:16:02,333 Increasing the stresses 1970 01:16:02,333 --> 01:16:04,432 At the base of the building, 1971 01:16:04,432 --> 01:16:05,499 Now we're unlikely to see 1972 01:16:05,499 --> 01:16:06,799 A skyscraper fall 1973 01:16:06,799 --> 01:16:09,266 Like a tree in the forest. 1974 01:16:09,266 --> 01:16:11,799 Once it does start to incline, 1975 01:16:11,799 --> 01:16:13,599 Gravitational force will cause 1976 01:16:13,599 --> 01:16:15,133 The top of the building 1977 01:16:15,133 --> 01:16:16,099 To collapse downward 1978 01:16:16,099 --> 01:16:18,499 On top of itself. 1979 01:16:21,899 --> 01:16:23,766 decay has also overtaken 1980 01:16:23,766 --> 01:16:25,732 The city of Chicago, 1981 01:16:25,732 --> 01:16:26,532 The birthplace 1982 01:16:26,532 --> 01:16:31,499 Of the skyscraper. 1983 01:16:31,499 --> 01:16:32,766 The sears tower, 1984 01:16:32,766 --> 01:16:34,199 The tallest man-made structure 1985 01:16:34,199 --> 01:16:35,799 In North America, 1986 01:16:35,799 --> 01:16:36,333 Has reached 1987 01:16:36,333 --> 01:16:40,233 The end of its reign. 1988 01:17:00,633 --> 01:17:02,032 The first 500 years 1989 01:17:02,032 --> 01:17:04,032 After people has been an era 1990 01:17:04,032 --> 01:17:13,333 Of decay and destruction. 1991 01:17:13,333 --> 01:17:14,700 Our concrete structures 1992 01:17:14,700 --> 01:17:17,865 Have lasted the longest. 1993 01:17:17,865 --> 01:17:18,965 The ancient Romans 1994 01:17:18,965 --> 01:17:20,166 Invented the first form 1995 01:17:20,166 --> 01:17:22,899 Of concrete. 1996 01:17:22,899 --> 01:17:24,099 And some of their structures 1997 01:17:24,099 --> 01:17:25,232 Remained intact 1998 01:17:25,232 --> 01:17:29,566 For over 2,000 years. 1999 01:17:29,566 --> 01:17:30,800 But modern concrete 2000 01:17:30,800 --> 01:17:32,766 Isn't nearly as durable. 2001 01:17:32,766 --> 01:17:34,800 It has higher water content 2002 01:17:34,800 --> 01:17:36,733 And is more loosely packed, 2003 01:17:36,733 --> 01:17:37,666 Which leads to more? 2004 01:17:37,666 --> 01:17:40,899 Air pockets and cracks. 2005 01:17:40,899 --> 01:17:42,032 Modern concrete structures 2006 01:17:42,032 --> 01:17:45,232 Have another fatal flaw. 2007 01:17:45,299 --> 01:17:45,932 below the surface 2008 01:17:45,932 --> 01:17:46,499 Of reinforced 2009 01:17:46,499 --> 01:17:47,700 Concrete structures, 2010 01:17:47,700 --> 01:17:48,832 There is a mesh 2011 01:17:48,832 --> 01:17:50,700 Of steel reinforcing bars 2012 01:17:50,700 --> 01:17:52,433 And they don't corrode 2013 01:17:52,433 --> 01:17:54,366 Because the concrete maintains 2014 01:17:54,499 --> 01:17:55,832 An alkaline environment 2015 01:17:55,832 --> 01:17:56,999 Around them. 2016 01:17:56,999 --> 01:17:58,433 Now, when that alkalinity 2017 01:17:58,433 --> 01:17:59,499 Breaks down, 2018 01:17:59,499 --> 01:18:00,865 As it will in time, 2019 01:18:00,865 --> 01:18:01,599 Then the steel 2020 01:18:01,599 --> 01:18:05,733 Will start to corrode. 2021 01:18:05,733 --> 01:18:07,633 as the steel rebar rusts, 2022 01:18:07,633 --> 01:18:09,733 It expands to three times 2023 01:18:09,733 --> 01:18:11,533 Its original volume 2024 01:18:11,533 --> 01:18:13,099 Creating an outward pressure 2025 01:18:13,099 --> 01:18:14,566 That causes the concrete 2026 01:18:14,566 --> 01:18:22,466 To crumble. 2027 01:18:22,466 --> 01:18:23,499 in very broad terms, 2028 01:18:23,499 --> 01:18:24,566 After 50 years 2029 01:18:24,566 --> 01:18:25,299 We'd start to see 2030 01:18:25,299 --> 01:18:27,533 Surface cracking on concrete. 2031 01:18:27,533 --> 01:18:29,066 After a hundred years, 2032 01:18:29,066 --> 01:18:31,166 Flaking of the concrete surface. 2033 01:18:31,166 --> 01:18:32,800 After maybe 500 years, 2034 01:18:32,800 --> 01:18:33,733 Most reinforced 2035 01:18:33,733 --> 01:18:34,965 Concrete structures 2036 01:18:34,965 --> 01:18:38,932 Will be gone. 2037 01:18:38,932 --> 01:18:40,032 we look at these images 2038 01:18:40,032 --> 01:18:46,533 Of our fallen civilization, 2039 01:18:46,533 --> 01:18:47,666 It helps us to identify 2040 01:18:47,666 --> 01:18:48,766 With the past, 2041 01:18:48,766 --> 01:18:50,466 With the Greeks and the Romans, 2042 01:18:50,466 --> 01:18:52,199 With the crumbled 2043 01:18:52,199 --> 01:18:54,599 Mud brick cities of urn. 2044 01:18:54,666 --> 01:18:55,299 Each of us knows 2045 01:18:55,299 --> 01:18:56,032 That our bodies 2046 01:18:56,032 --> 01:18:59,266 Are going to fall apart; 2047 01:18:59,266 --> 01:19:03,999 Why not our cities too? 2048 01:19:08,899 --> 01:19:10,666 a thousand years ago, 2049 01:19:10,666 --> 01:19:12,733 6 1/2 billion people 2050 01:19:12,733 --> 01:19:16,533 Called this planet home. 2051 01:19:16,533 --> 01:19:19,066 At the early 21st century, 2052 01:19:19,066 --> 01:19:20,066 More than half of them 2053 01:19:20,066 --> 01:19:26,599 Lived in cities. 2054 01:19:26,599 --> 01:19:28,499 Now those cities 2055 01:19:28,499 --> 01:19:32,700 Are unrecognizable. 2056 01:19:32,700 --> 01:19:34,099 after maybe a thousand years 2057 01:19:34,099 --> 01:19:35,800 Or so, the scene behind me 2058 01:19:35,800 --> 01:19:38,399 Would be very, very different. 2059 01:19:38,399 --> 01:19:39,399 There'll be very little evidence 2060 01:19:39,399 --> 01:19:41,700 Of buildings, 2061 01:19:41,700 --> 01:19:42,566 Very little evidence 2062 01:19:42,566 --> 01:19:44,266 Of the activities of man. 2063 01:19:44,266 --> 01:19:45,199 What we would see 2064 01:19:45,199 --> 01:19:49,132 Would be a jungle of vegetation. 2065 01:19:49,132 --> 01:19:50,499 the future of cities 2066 01:19:50,499 --> 01:19:52,166 In a life after people 2067 01:19:52,166 --> 01:19:53,733 Can be best imagined 2068 01:19:53,733 --> 01:19:57,099 By looking to the past. 2069 01:19:57,166 --> 01:19:58,199 this is minute street 2070 01:19:58,199 --> 01:20:00,066 In Greenwich Village. 2071 01:20:00,066 --> 01:20:01,132 Most new Yorkers might come here 2072 01:20:01,132 --> 01:20:02,166 And wonder why it curves 2073 01:20:02,166 --> 01:20:04,132 Like this. 2074 01:20:04,132 --> 01:20:04,700 It curves 2075 01:20:04,700 --> 01:20:05,865 Because once upon a time 2076 01:20:05,865 --> 01:20:06,999 There was a stream here, 2077 01:20:06,999 --> 01:20:08,466 And then a brook. 2078 01:20:08,466 --> 01:20:09,599 There were more than 40 streams 2079 01:20:09,599 --> 01:20:14,999 On Manhattan island. 2080 01:20:22,399 --> 01:20:23,399 All flowing down 2081 01:20:23,399 --> 01:20:24,700 And carrying the rainwater 2082 01:20:24,700 --> 01:20:27,433 Down to the sea. 2083 01:20:27,433 --> 01:20:28,633 So what happens today? 2084 01:20:28,633 --> 01:20:30,832 The rain falls, the snow melts, 2085 01:20:30,832 --> 01:20:31,466 But it flows 2086 01:20:31,466 --> 01:20:32,865 Right along the street 2087 01:20:32,865 --> 01:20:34,032 And down into that storm drain 2088 01:20:34,032 --> 01:20:35,399 There. 2089 01:20:35,399 --> 01:20:36,266 If there weren't people here 2090 01:20:36,266 --> 01:20:37,466 Anymore, there'll be no one here 2091 01:20:37,466 --> 01:20:38,999 To maintain the sidewalks 2092 01:20:38,999 --> 01:20:40,299 And maintain the streets. 2093 01:20:40,299 --> 01:20:41,766 They'd start to crumble up. 2094 01:20:41,766 --> 01:20:43,499 They'd start to break apart. 2095 01:20:43,499 --> 01:20:44,433 Trees would come back, 2096 01:20:44,433 --> 01:20:45,700 Vegetation would come back, 2097 01:20:45,700 --> 01:20:46,232 And eventually 2098 01:20:46,232 --> 01:20:47,466 The hydrological cycle 2099 01:20:47,466 --> 01:20:48,965 Would reestablish itself. 2100 01:20:48,965 --> 01:20:49,865 And who knows, 2101 01:20:49,865 --> 01:20:51,399 Maybe Minute Street 2102 01:20:51,399 --> 01:20:52,366 Might once again 2103 01:20:52,366 --> 01:20:55,499 Become minute brook. 2104 01:20:55,499 --> 01:20:57,166 using historic maps 2105 01:20:57,166 --> 01:20:58,666 And computer modeling, 2106 01:20:58,666 --> 01:20:59,733 Scientists 2107 01:20:59,733 --> 01:21:01,032 With the Manhattan project 2108 01:21:01,032 --> 01:21:02,800 Are rediscovering 2109 01:21:02,800 --> 01:21:04,032 What Manhattan Island 2110 01:21:04,032 --> 01:21:05,932 Looked like when explorer 2111 01:21:05,932 --> 01:21:07,965 Henry Hudson first sailed 2112 01:21:07,965 --> 01:21:14,199 Around its shores in 1609. 2113 01:21:14,199 --> 01:21:15,899 here we are in Foley square, 2114 01:21:15,899 --> 01:21:16,733 The administrative center 2115 01:21:16,733 --> 01:21:17,965 Of New York City 2116 01:21:17,965 --> 01:21:18,865 And location to the famous 2117 01:21:18,865 --> 01:21:22,299 Courthouses you see on TV. 2118 01:21:22,299 --> 01:21:23,366 This place hasn't always had 2119 01:21:23,366 --> 01:21:24,599 Such colossal buildings 2120 01:21:24,599 --> 01:21:26,299 And stony streets. 2121 01:21:26,299 --> 01:21:28,399 Once upon a time, 400 years ago, 2122 01:21:28,399 --> 01:21:29,666 The collect pond was here, 2123 01:21:29,666 --> 01:21:30,865 The freshwater source 2124 01:21:30,865 --> 01:21:31,766 For New York City. 2125 01:21:31,766 --> 01:21:33,132 Right behind me, 2126 01:21:33,132 --> 01:21:34,399 There was a stream that drained 2127 01:21:34,399 --> 01:21:36,832 Down to the Hudson River shore, 2128 01:21:36,832 --> 01:21:37,399 Another stream 2129 01:21:37,399 --> 01:21:38,865 To the east river. 2130 01:21:38,865 --> 01:21:39,499 And there was 2131 01:21:39,499 --> 01:21:40,132 This beautiful pond 2132 01:21:40,132 --> 01:21:40,733 That was nestled 2133 01:21:40,733 --> 01:21:43,166 In an amphitheater of hills. 2134 01:21:43,166 --> 01:21:44,166 So what would happen? 2135 01:21:44,166 --> 01:21:44,700 If all the people 2136 01:21:44,700 --> 01:21:49,599 Were to disappear? 2137 01:21:49,599 --> 01:21:50,066 The buildings, 2138 01:21:50,066 --> 01:21:51,366 They would tumble down. 2139 01:21:51,366 --> 01:21:52,965 The soil would start to reform. 2140 01:21:52,965 --> 01:21:53,832 Trees would start to grow 2141 01:21:53,832 --> 01:21:54,733 Out of them. 2142 01:21:54,733 --> 01:21:56,466 They would become the new hills, 2143 01:21:56,466 --> 01:21:57,199 The new amphitheater 2144 01:21:57,199 --> 01:22:00,965 Around this place. 2145 01:22:00,965 --> 01:22:02,832 Nature would reestablish itself 2146 01:22:02,832 --> 01:22:03,832 And slowly bring this place 2147 01:22:03,832 --> 01:22:05,566 Back into the green heart 2148 01:22:05,566 --> 01:22:07,199 Of what it means to be here 2149 01:22:07,199 --> 01:22:17,599 On planet earth. 2150 01:22:17,599 --> 01:22:19,166 new York city, 2151 01:22:19,166 --> 01:22:20,932 Like the rest of the planet, 2152 01:22:20,932 --> 01:22:34,999 Has changed radically. 2153 01:22:34,999 --> 01:22:36,032 The transformation 2154 01:22:36,032 --> 01:22:39,466 Is most shocking in Times Square? 2155 01:22:39,466 --> 01:22:40,533 As the once beating 2156 01:22:40,533 --> 01:22:43,132 Heart of the city is silenced 2157 01:22:43,132 --> 01:23:17,965 By nature's onslaught. 2158 01:23:17,965 --> 01:23:22,366 It's 10,000 years after people. 2159 01:23:24,199 --> 01:23:25,633 Could it be possible? 2160 01:23:25,633 --> 01:23:28,132 After only 10 millennia 2161 01:23:28,132 --> 01:23:29,666 That humanity has vanished 2162 01:23:29,666 --> 01:23:40,733 Without a trace? 2163 01:23:40,733 --> 01:23:42,766 Human scientists once predicted 2164 01:23:42,766 --> 01:23:44,533 That our history and culture 2165 01:23:44,533 --> 01:23:46,166 Would live on through our radio 2166 01:23:46,166 --> 01:23:48,599 And television broadcasts, 2167 01:23:48,599 --> 01:23:49,499 Which carry on? 2168 01:23:49,499 --> 01:23:50,266 Through the universe 2169 01:23:50,266 --> 01:23:53,965 Toward the infinite, 2170 01:23:53,965 --> 01:23:55,399 Perhaps to be tuned in 2171 01:23:55,399 --> 01:23:57,166 By an intelligent species 2172 01:23:57,166 --> 01:23:59,633 On a distant planet. 2173 01:23:59,633 --> 01:24:00,166 some people think 2174 01:24:00,166 --> 01:24:01,700 That there's an expanding shell 2175 01:24:01,700 --> 01:24:03,999 Of radio and television 2176 01:24:03,999 --> 01:24:06,700 From earth, expanding outward 2177 01:24:06,700 --> 01:24:09,199 Alerting the universe, 2178 01:24:09,199 --> 01:24:10,299 "here we are 2179 01:24:10,299 --> 01:24:17,166 And this is our culture." 2180 01:24:17,232 --> 01:24:17,899 Unfortunately, 2181 01:24:17,899 --> 01:24:18,999 Recent calculations 2182 01:24:18,999 --> 01:24:21,566 By of all people, the seta, 2183 01:24:21,566 --> 01:24:22,766 Search for extraterrestrial 2184 01:24:22,766 --> 01:24:25,132 Intelligence group, 2185 01:24:25,132 --> 01:24:26,433 Has shown that all 2186 01:24:26,433 --> 01:24:27,633 Of this dissipates 2187 01:24:27,633 --> 01:24:29,099 Within one and two light-years 2188 01:24:29,099 --> 01:24:32,566 Into noise. 2189 01:24:32,566 --> 01:24:34,299 if this is true, 2190 01:24:34,299 --> 01:24:35,733 Our signals won't even make it 2191 01:24:35,733 --> 01:24:37,266 Out to the newest star 2192 01:24:37,266 --> 01:24:42,832 Beyond the sun. 2193 01:24:45,533 --> 01:24:47,965 So what will remain 10,000 years? 2194 01:24:47,965 --> 01:24:50,633 After people to tell the story 2195 01:24:50,633 --> 01:24:52,466 Of the once great civilizations 2196 01:24:52,466 --> 01:24:54,832 That walked the earth? 2197 01:24:54,832 --> 01:24:57,066 Iron corrodes, 2198 01:24:57,066 --> 01:24:59,533 Concrete crumbles, 2199 01:24:59,533 --> 01:25:03,266 Wood and paper decay. 2200 01:25:03,266 --> 01:25:05,066 Still, some of what man 2201 01:25:05,066 --> 01:25:10,132 Built on earth remains. 2202 01:25:10,132 --> 01:25:11,232 The most colossal 2203 01:25:11,232 --> 01:25:13,066 Of our stone structures 2204 01:25:13,066 --> 01:25:15,132 Like the Great Wall of China 2205 01:25:15,132 --> 01:25:17,466 Have aged like mountains, 2206 01:25:17,466 --> 01:25:19,366 Subject to erosion, 2207 01:25:19,366 --> 01:25:21,499 But at such slow time scales, 2208 01:25:21,499 --> 01:25:23,199 They will still be recognizable 2209 01:25:23,199 --> 01:25:27,733 In some form for eons. 2210 01:25:27,733 --> 01:25:29,499 The great pyramid at Giza 2211 01:25:29,499 --> 01:25:31,700 Is so massive that it lasts 2212 01:25:31,700 --> 01:25:33,566 Long enough to be swallowed up 2213 01:25:33,566 --> 01:25:39,999 By the desert sands. 2214 01:25:39,999 --> 01:25:41,433 The hover dam 2215 01:25:41,433 --> 01:25:42,700 Built to be as tough 2216 01:25:42,700 --> 01:25:45,199 As the canyon walls around it 2217 01:25:45,199 --> 01:25:46,199 Is one of the last? 2218 01:25:46,199 --> 01:25:47,599 Man-made structures 2219 01:25:47,599 --> 01:25:50,399 Still standing. 2220 01:25:50,399 --> 01:25:53,466 But now thousands of years 2221 01:25:53,466 --> 01:25:54,899 In the future, 2222 01:25:54,899 --> 01:25:56,932 Earth is about to be visited 2223 01:25:56,932 --> 01:25:57,965 By the last 2224 01:25:57,965 --> 01:26:04,533 Of the great collapses. 2225 01:26:04,533 --> 01:26:05,433 it's the environment 2226 01:26:05,433 --> 01:26:07,466 That eventually wins. 2227 01:26:07,466 --> 01:26:18,899 Earthquakes, sandstorms, rain. 2228 01:26:18,899 --> 01:26:21,166 But there are a few exceptions. 2229 01:26:21,166 --> 01:26:22,299 I would have to say 2230 01:26:22,299 --> 01:26:24,433 That mounts Rushmore, 2231 01:26:24,433 --> 01:26:26,999 Carved out of solid granite 2232 01:26:26,999 --> 01:26:30,266 In an ecologically stable place, 2233 01:26:30,266 --> 01:26:32,266 The only enemy it has 2234 01:26:32,266 --> 01:26:35,899 Are wind-driven pellets of rain? 2235 01:26:35,899 --> 01:26:36,800 I think that mount Rushmore 2236 01:26:36,800 --> 01:26:38,166 May be around 2237 01:26:38,166 --> 01:26:39,266 A hundred thousand years, 2238 01:26:39,266 --> 01:26:41,199 Possibly 200. 2239 01:26:41,199 --> 01:26:42,266 Possibly even in time 2240 01:26:42,266 --> 01:26:45,199 To be looked at in awe 2241 01:26:45,199 --> 01:26:46,999 By the earliest 2242 01:26:46,999 --> 01:26:53,366 Of our replacements. 2243 01:26:53,366 --> 01:26:55,166 and who or what might 2244 01:26:55,166 --> 01:26:59,832 Those replacements are? 2245 01:26:59,832 --> 01:27:02,333 Perhaps chimpanzees 2246 01:27:02,333 --> 01:27:06,099 Might somehow make the leap. 2247 01:27:06,099 --> 01:27:08,666 but we have to consider this: 2248 01:27:08,666 --> 01:27:10,333 Some scientists believe 2249 01:27:10,333 --> 01:27:12,499 That it's easy for nature 2250 01:27:12,499 --> 01:27:13,266 To bring animals 2251 01:27:13,266 --> 01:27:15,666 Up to a clever level 2252 01:27:15,666 --> 01:27:17,499 Where they might use tools, 2253 01:27:17,499 --> 01:27:18,533 They might become masters 2254 01:27:18,533 --> 01:27:21,733 Of their environment. 2255 01:27:21,733 --> 01:27:23,099 But the leap to being able 2256 01:27:23,099 --> 01:27:24,700 To stare at the sky 2257 01:27:24,700 --> 01:27:27,965 And imagine a cosmos, 2258 01:27:27,965 --> 01:27:28,865 To be able 2259 01:27:28,865 --> 01:27:30,266 To contemplate yourself, 2260 01:27:30,266 --> 01:27:31,199 To be able to contemplate 2261 01:27:31,199 --> 01:27:35,965 Your own role in the earth, 2262 01:27:35,965 --> 01:27:37,066 This may be a leap 2263 01:27:37,066 --> 01:27:38,599 That was a sheer accident 2264 01:27:38,599 --> 01:27:40,733 For humanity. 2265 01:27:40,733 --> 01:27:41,433 In which case, 2266 01:27:41,433 --> 01:27:42,666 You're not talking 2267 01:27:42,666 --> 01:27:45,132 About a complete recovery. 2268 01:27:45,132 --> 01:27:46,099 You're talking about a planet 2269 01:27:46,099 --> 01:27:49,932 That may continue, 2270 01:27:49,932 --> 01:27:51,466 But nobody to talk about it, 2271 01:27:51,466 --> 01:27:56,399 Nobody to think about it. 2272 01:27:56,466 --> 01:27:57,066 if earth's 2273 01:27:57,066 --> 01:28:00,333 4 1/2 billion years of existence 2274 01:28:00,333 --> 01:28:03,466 Were condensed into 24 hours, 2275 01:28:03,466 --> 01:28:06,299 The passage of 10,000 years 2276 01:28:06,299 --> 01:28:09,366 Would be a fraction of a second. 2277 01:28:09,366 --> 01:28:11,599 Man's time on the planet so far 2278 01:28:11,599 --> 01:28:12,299 Would be 2279 01:28:12,299 --> 01:28:17,333 About half a minute long. 2280 01:28:17,333 --> 01:28:19,299 So, like an abandoned village 2281 01:28:19,299 --> 01:28:21,366 On a global scale, 2282 01:28:21,366 --> 01:28:22,666 The earth will move on 2283 01:28:22,666 --> 01:28:24,333 Without us. 2284 01:28:24,333 --> 01:28:26,266 There was life before people. 2285 01:28:26,965 --> 01:28:31,032 There will be life after people.