All language subtitles for Earth s01e05.eng

af Afrikaans
sq Albanian
am Amharic
ar Arabic
hy Armenian
az Azerbaijani
eu Basque
be Belarusian
bn Bengali
bs Bosnian
bg Bulgarian
ca Catalan
ceb Cebuano
ny Chichewa
zh-CN Chinese (Simplified)
zh-TW Chinese (Traditional)
co Corsican
hr Croatian
cs Czech
da Danish
nl Dutch Download
en English
eo Esperanto
et Estonian
tl Filipino
fi Finnish
fr French
fy Frisian
gl Galician
ka Georgian
de German
el Greek
gu Gujarati
ht Haitian Creole
ha Hausa
haw Hawaiian
iw Hebrew
hi Hindi
hmn Hmong
hu Hungarian
is Icelandic
ig Igbo
id Indonesian
ga Irish
it Italian
ja Japanese
jw Javanese
kn Kannada
kk Kazakh
km Khmer
ko Korean
ku Kurdish (Kurmanji)
ky Kyrgyz
lo Lao
la Latin
lv Latvian
lt Lithuanian
lb Luxembourgish
mk Macedonian
mg Malagasy
ms Malay
ml Malayalam
mt Maltese
mi Maori
mr Marathi
mn Mongolian
my Myanmar (Burmese)
ne Nepali
no Norwegian
ps Pashto
fa Persian
pl Polish
pt Portuguese
pa Punjabi
ro Romanian
ru Russian
sm Samoan
gd Scots Gaelic
sr Serbian
st Sesotho
sn Shona
sd Sindhi
si Sinhala
sk Slovak
sl Slovenian
so Somali
es Spanish
su Sundanese
sw Swahili
sv Swedish
tg Tajik
ta Tamil
te Telugu
th Thai
tr Turkish
uk Ukrainian
ur Urdu
uz Uzbek
vi Vietnamese
cy Welsh
xh Xhosa
yi Yiddish
yo Yoruba
zu Zulu
or Odia (Oriya)
rw Kinyarwanda
tk Turkmen
tt Tatar
ug Uyghur
Would you like to inspect the original subtitles? These are the user uploaded subtitles that are being translated: 1 00:00:49,120 --> 00:00:52,256 I've come here to Southwestern France to the Pyrenees 2 00:00:52,280 --> 00:00:55,976 and then deep into a mountain, more than half a kilometre 3 00:00:56,000 --> 00:00:58,576 through a labyrinth of damp and dark caves, 4 00:00:58,600 --> 00:01:02,496 into this enormous and remarkable cavern. 5 00:01:02,520 --> 00:01:05,496 But I've come here to show you something very special. 6 00:01:05,520 --> 00:01:06,880 Look at this. 7 00:01:11,400 --> 00:01:14,840 No less than eight bison... 8 00:01:15,840 --> 00:01:18,336 ..drawn on this cave wall. 9 00:01:18,360 --> 00:01:21,256 Absolutely beautiful. 10 00:01:21,280 --> 00:01:25,240 But it's not just these bison. Have a look at this panel over here! 11 00:01:28,280 --> 00:01:33,336 Here, we don't just see bison - we see primitive horses, tarpan. 12 00:01:33,360 --> 00:01:37,360 And look there, a Pyrenean ibex. 13 00:01:38,360 --> 00:01:41,160 Absolutely sensational. 14 00:01:47,280 --> 00:01:52,536 Now, I've stood in art galleries all over the world looking at art, 15 00:01:52,560 --> 00:01:55,400 but this is the oldest I've seen by far. 16 00:01:57,800 --> 00:02:00,280 And possibly the most beautiful and most moving. 17 00:02:01,880 --> 00:02:06,336 The drawings of these animals are so fresh, 18 00:02:06,360 --> 00:02:10,360 so accurate, so beautifully made. 19 00:02:11,640 --> 00:02:14,160 For me, this is about being human. 20 00:02:15,160 --> 00:02:17,640 This is about our history. 21 00:02:24,480 --> 00:02:28,376 The cave paintings are the culmination of a story 22 00:02:28,400 --> 00:02:32,480 that began long before the first humans set foot on Earth... 23 00:02:35,440 --> 00:02:38,560 ..deep within our planet's past... 24 00:02:40,440 --> 00:02:42,136 LOUD EXPLOSION 25 00:02:42,160 --> 00:02:44,400 ..when the world of the dinosaurs... 26 00:02:48,960 --> 00:02:50,360 ..was destroyed... 27 00:02:51,720 --> 00:02:55,000 ..making way for the rise of the mammals. 28 00:02:56,880 --> 00:03:00,816 It's a tale of turmoil and upheaval, 29 00:03:00,840 --> 00:03:04,616 of millions of years of climate swings 30 00:03:04,640 --> 00:03:07,800 from one extreme to another. 31 00:03:09,000 --> 00:03:11,416 Until, out of the chaos, 32 00:03:11,440 --> 00:03:15,896 our species was born. 33 00:03:15,920 --> 00:03:19,936 A species capable of creating art 34 00:03:19,960 --> 00:03:22,680 on a cave wall in Southern France. 35 00:03:24,160 --> 00:03:28,656 Now, we think that these were drawn around 13,000 years ago. 36 00:03:28,680 --> 00:03:33,136 And that's significant because it constitutes a turning point, 37 00:03:33,160 --> 00:03:35,936 not just for our species, but for the planet, 38 00:03:35,960 --> 00:03:41,056 because we were going on to be a significantly powerful force, 39 00:03:41,080 --> 00:03:45,160 capable of transforming and reshaping the Earth. 40 00:03:49,280 --> 00:03:53,096 In the time since the cave paintings were done, 41 00:03:53,120 --> 00:03:57,120 we've radically altered life on the planet... 42 00:03:58,880 --> 00:04:04,160 ..in ways our ancient ancestors could never have imagined. 43 00:04:07,600 --> 00:04:10,896 And so we've reached a unique point in our planet's 44 00:04:10,920 --> 00:04:15,256 4.5 billion year history, when an intelligent species, 45 00:04:15,280 --> 00:04:18,176 with a clear understanding of the Earth, 46 00:04:18,200 --> 00:04:21,056 is transforming it at an incredible speed. 47 00:04:21,080 --> 00:04:24,320 And that species is, of course, us. 48 00:05:00,160 --> 00:05:02,736 66 million years ago, 49 00:05:02,760 --> 00:05:06,840 one form of life dominated the surface of the Earth. 50 00:05:11,240 --> 00:05:13,176 DEEP GROWLING 51 00:05:13,200 --> 00:05:14,680 Dinosaurs. 52 00:05:16,640 --> 00:05:20,816 These magnificent creatures, amongst the largest that have ever lived 53 00:05:20,840 --> 00:05:26,600 on Earth, had reigned supreme for around 150 million years. 54 00:05:33,400 --> 00:05:37,096 They had evolved into many hundreds of species, 55 00:05:37,120 --> 00:05:40,640 spread across every continent on the planet. 56 00:05:48,160 --> 00:05:51,480 But all that was about to change. 57 00:06:22,520 --> 00:06:26,376 What a wonderful place, packed full of life. 58 00:06:26,400 --> 00:06:29,176 I've just been looking up into the forest here. 59 00:06:29,200 --> 00:06:32,536 Tanagers, aracari, orioles - 60 00:06:32,560 --> 00:06:34,936 a mass of species. 61 00:06:34,960 --> 00:06:38,656 Now, of course, all of them are individually beautiful. 62 00:06:38,680 --> 00:06:42,696 But, for me, it's when they form that complex web, 63 00:06:42,720 --> 00:06:46,856 when they knit together to form a dynamic, harmonious, 64 00:06:46,880 --> 00:06:51,856 functional ecosystem that things become even more beautiful. 65 00:06:51,880 --> 00:06:53,816 But I've got to say, of course, 66 00:06:53,840 --> 00:06:56,776 that none of these species were predestined. 67 00:06:56,800 --> 00:06:58,896 They weren't "meant to be". 68 00:06:58,920 --> 00:07:04,496 In fact, they were only here because of a single, freak, chance event. 69 00:07:04,520 --> 00:07:08,376 An event of unimaginable violence 70 00:07:08,400 --> 00:07:10,736 and astonishing destruction. 71 00:07:10,760 --> 00:07:14,736 I'm talking, of course, about that day 66 million years ago 72 00:07:14,760 --> 00:07:16,976 when the asteroid struck the Earth. 73 00:07:17,000 --> 00:07:18,176 You know the one - 74 00:07:18,200 --> 00:07:20,800 the one that's said to have wiped out the dinosaurs. 75 00:07:25,560 --> 00:07:28,816 Now, there has been lots of debate about exactly 76 00:07:28,840 --> 00:07:30,800 what killed the dinosaurs. 77 00:07:34,200 --> 00:07:36,376 Since the 1980s, 78 00:07:36,400 --> 00:07:41,000 scientists have believed the main culprit was an asteroid... 79 00:07:44,720 --> 00:07:48,696 ..from the far reaches of the solar system, 80 00:07:48,720 --> 00:07:51,920 the size of Mount Everest... 81 00:07:53,520 --> 00:07:56,560 ..and on a collision course with Earth. 82 00:08:05,880 --> 00:08:10,336 An extraordinary claim requires some extraordinary evidence 83 00:08:10,360 --> 00:08:13,816 and, let's be clear, claiming that a six mile wide asteroid 84 00:08:13,840 --> 00:08:16,376 crashed into the planet, unleashing the power 85 00:08:16,400 --> 00:08:19,656 of a billion nuclear weapons is an extraordinary claim. 86 00:08:19,680 --> 00:08:21,616 So where is the evidence? 87 00:08:21,640 --> 00:08:23,616 Where is the smoking gun? 88 00:08:23,640 --> 00:08:26,496 Well, I'm sat in it. 89 00:08:26,520 --> 00:08:29,576 This is called a cenote. 90 00:08:29,600 --> 00:08:32,016 It's a word that comes from one of the Mayan languages. 91 00:08:32,040 --> 00:08:35,720 It literally means hole in the ground filled with water. 92 00:08:36,920 --> 00:08:40,456 Now, take a look at this map of this part of Mexico, 93 00:08:40,480 --> 00:08:43,536 the Yucatan Peninsula. 94 00:08:43,560 --> 00:08:47,696 When I superimpose the cenotes, you see there's an enormous 95 00:08:47,720 --> 00:08:50,496 number of them, the landscape is completely freckled. 96 00:08:50,520 --> 00:08:52,936 But then look again in more detail. 97 00:08:52,960 --> 00:08:54,416 You see this here? 98 00:08:54,440 --> 00:08:58,656 There's an arc of these geological features running across here. 99 00:08:58,680 --> 00:09:01,896 And if we complete the arc, turning it into a circle, 100 00:09:01,920 --> 00:09:06,856 it has a diameter of 110 miles, which corresponds perfectly 101 00:09:06,880 --> 00:09:10,336 with the inner rim of the crater made 102 00:09:10,360 --> 00:09:13,496 when the asteroid struck our planet. 103 00:09:13,520 --> 00:09:16,336 Now, the cenotes weren't formed at the time. 104 00:09:16,360 --> 00:09:19,416 Over millions of years, that impact seems to have weakened 105 00:09:19,440 --> 00:09:21,096 the rock here. 106 00:09:21,120 --> 00:09:24,216 Water has leached through it, forming cave systems, 107 00:09:24,240 --> 00:09:28,656 which have collapsed in some places, giving us this ring of cenotes. 108 00:09:28,680 --> 00:09:31,400 HIGH PITCHED BIRD CALL 109 00:09:36,080 --> 00:09:40,200 A devastating remnant of the asteroid strike... 110 00:09:45,000 --> 00:09:49,360 ..that brought the reign of the dinosaurs to a crashing end. 111 00:09:56,880 --> 00:09:59,200 SHARP, LOUD BLAST 112 00:10:00,840 --> 00:10:04,360 DEEP SCREECHING 113 00:10:07,280 --> 00:10:10,680 LOUD RUMBLING 114 00:10:14,480 --> 00:10:16,560 THUNDERING BOOM 115 00:10:24,280 --> 00:10:27,280 The blast annihilates everything within its reach. 116 00:10:33,000 --> 00:10:36,200 Earthquakes and tsunami tear across the planet. 117 00:10:41,760 --> 00:10:44,800 And then it begins to rain. 118 00:10:47,280 --> 00:10:48,720 Not water... 119 00:10:49,920 --> 00:10:52,576 ..but scorching hot rock... 120 00:10:52,600 --> 00:10:56,296 DINOSAUR ROARS 121 00:10:56,320 --> 00:10:59,776 ..made from the asteroid and the bedrock it had struck. 122 00:10:59,800 --> 00:11:03,000 ANGUISHED ROARS 123 00:11:06,760 --> 00:11:11,616 Truly one of THE worst days in Earth's history. 124 00:11:11,640 --> 00:11:15,360 DINOSAUR ROARS 125 00:11:21,400 --> 00:11:24,736 But was this cataclysm enough to kill the dinosaurs 126 00:11:24,760 --> 00:11:27,240 all over the planet? 127 00:11:32,360 --> 00:11:35,776 For a species to become fully extinct, 128 00:11:35,800 --> 00:11:41,056 every member of that species has to die and not be replaced, 129 00:11:41,080 --> 00:11:44,776 and not just in a small area or even over a continent, 130 00:11:44,800 --> 00:11:47,856 but over the entire world. 131 00:11:47,880 --> 00:11:51,656 That's what extinction's really about, that's what it entails. 132 00:11:51,680 --> 00:11:56,440 And generally, it's not a dramatic process, it's a slow burner. 133 00:11:57,560 --> 00:11:58,880 Have a look at this. 134 00:12:00,480 --> 00:12:03,400 In my bag here, I've got the skull... 135 00:12:04,840 --> 00:12:08,616 ..of an ornithomimid dinosaur - 136 00:12:08,640 --> 00:12:10,936 one of a group of dinosaurs. 137 00:12:10,960 --> 00:12:14,576 These creatures looked rather like giant ostrich 138 00:12:14,600 --> 00:12:16,736 and they could run really fast. 139 00:12:16,760 --> 00:12:20,936 But the key thing is that these ornithomimids can be found all over 140 00:12:20,960 --> 00:12:23,296 the world in the fossil record. 141 00:12:23,320 --> 00:12:26,880 So how did they become extinct? 142 00:12:28,360 --> 00:12:32,416 Well, those that were unlucky enough to be living within the blast radius 143 00:12:32,440 --> 00:12:35,416 of the asteroid, the answer's simple - 144 00:12:35,440 --> 00:12:38,416 they just vaporised instantaneously. 145 00:12:38,440 --> 00:12:41,616 LOUD, DEEP BLAST 146 00:12:41,640 --> 00:12:44,096 And those living a little further away, 147 00:12:44,120 --> 00:12:46,416 say within thousands of miles, 148 00:12:46,440 --> 00:12:50,016 well, it's likely they were killed by the aftermath effects 149 00:12:50,040 --> 00:12:51,280 of that strike. 150 00:12:53,120 --> 00:12:56,816 Things like earthquakes, tsunamis, 151 00:12:56,840 --> 00:12:59,000 the glass rain and the forest fires. 152 00:13:00,240 --> 00:13:02,776 But what about the ornithomimids that were living, say, 153 00:13:02,800 --> 00:13:05,416 on the other side of the world, as far away as possible 154 00:13:05,440 --> 00:13:09,256 from the immediate carnage that was caused by that asteroid? 155 00:13:09,280 --> 00:13:11,560 How did THEY die? 156 00:13:16,440 --> 00:13:21,376 Well, something else was needed to cause the worldwide mass extinction. 157 00:13:21,400 --> 00:13:24,280 DEEP RUMBLING EXPLOSIONS 158 00:13:29,960 --> 00:13:32,496 To seek answers to this puzzle, 159 00:13:32,520 --> 00:13:35,960 scientists have drilled deep into the asteroid crater. 160 00:13:37,120 --> 00:13:41,040 The samples they've retrieved reveal important clues. 161 00:13:44,240 --> 00:13:49,400 Such as the fine-grain debris churned up by the powerful tsunami. 162 00:13:51,480 --> 00:13:56,096 As well as rocks like granite, melted by the incredible temperature 163 00:13:56,120 --> 00:13:58,760 and pressure created by the impact. 164 00:14:04,440 --> 00:14:10,136 But, crucially, one type of rock that's known to exist in this area 165 00:14:10,160 --> 00:14:14,120 is missing from the place where the asteroid hit. 166 00:14:15,640 --> 00:14:18,336 This is anhydrite. 167 00:14:18,360 --> 00:14:20,096 Now, I know what you're thinking. 168 00:14:20,120 --> 00:14:22,696 You're thinking this is a rather boring, grey rock. 169 00:14:22,720 --> 00:14:28,056 But what's important is that it contains large amounts of sulphur, 170 00:14:28,080 --> 00:14:33,616 and this is the final piece of our extinction jigsaw 171 00:14:33,640 --> 00:14:37,696 because, when the asteroid struck, it vaporised this rock, 172 00:14:37,720 --> 00:14:42,976 releasing no less than 300 billion tonnes of sulphur 173 00:14:43,000 --> 00:14:44,840 into the atmosphere. 174 00:14:46,640 --> 00:14:51,096 Today, there's virtually no trace of anhydrite in the seabed 175 00:14:51,120 --> 00:14:52,760 within the crater... 176 00:14:53,960 --> 00:14:57,040 ..because it was all blasted into the air... 177 00:15:03,880 --> 00:15:09,480 ..merging with ash and dust to form a vast, grey cloud... 178 00:15:17,040 --> 00:15:20,040 ..sweeping across the entire planet. 179 00:15:30,680 --> 00:15:34,216 With the cloud blocking out most of the sunlight, 180 00:15:34,240 --> 00:15:37,200 temperatures plummet by around 20 degrees. 181 00:15:39,400 --> 00:15:42,400 But the extreme cold isn't the only killer. 182 00:15:45,840 --> 00:15:48,656 In the dark, twilight conditions, 183 00:15:48,680 --> 00:15:52,760 plants struggle to photosynthesise and wither away. 184 00:15:55,680 --> 00:16:00,600 And with virtually no plants to eat, the food chain collapses. 185 00:16:03,920 --> 00:16:07,240 Many dinosaurs starve to death. 186 00:16:12,160 --> 00:16:16,056 When it came to the dinosaurs, only a handful hung on to evolve 187 00:16:16,080 --> 00:16:20,040 into the 10,000 or so species of birds that we have today. 188 00:16:21,520 --> 00:16:27,456 Three quarters of all animal and plant species simply disappear. 189 00:16:27,480 --> 00:16:32,240 This was one of the worst extinction events our planet has ever seen. 190 00:17:02,760 --> 00:17:06,376 And yet, for our world to emerge, 191 00:17:06,400 --> 00:17:09,200 there needed to be some survivors. 192 00:17:11,320 --> 00:17:16,720 And most importantly from that branch of life that we belong to... 193 00:17:19,160 --> 00:17:20,800 ..the mammals. 194 00:17:33,920 --> 00:17:35,496 What a place. 195 00:17:35,520 --> 00:17:38,456 It's not representative of humanity's greatest attributes, 196 00:17:38,480 --> 00:17:40,776 is it? It's a mess. 197 00:17:40,800 --> 00:17:43,776 An apocalyptic landfill, 198 00:17:43,800 --> 00:17:47,440 screaming of waste and consumption. 199 00:17:48,560 --> 00:17:50,736 I suppose the one thing we can say is, 200 00:17:50,760 --> 00:17:53,336 "Look, nature's always fighting back, isn't it?" 201 00:17:53,360 --> 00:17:57,096 Look at the plants here and, out there, a whole host of wildfowl. 202 00:17:57,120 --> 00:17:59,896 But let's stick with the mammals 203 00:17:59,920 --> 00:18:04,536 because 66 million years ago they didn't all become extinct 204 00:18:04,560 --> 00:18:08,816 and this is actually quite a good place to find a modern creature 205 00:18:08,840 --> 00:18:11,136 that shares some real characteristics 206 00:18:11,160 --> 00:18:13,136 with those early mammals, 207 00:18:13,160 --> 00:18:17,136 and I happen to have a very friendly one inside my jacket. 208 00:18:17,160 --> 00:18:18,776 What do you reckon? 209 00:18:18,800 --> 00:18:19,840 I'll show you. 210 00:18:21,080 --> 00:18:23,576 Yes! The rat. 211 00:18:23,600 --> 00:18:26,216 Now, I'm rather partial to rats, I've got to say. 212 00:18:26,240 --> 00:18:27,976 Just look at those whiskers. 213 00:18:28,000 --> 00:18:30,016 Those lovely bright eyes. 214 00:18:30,040 --> 00:18:32,576 But you might not be quite so enamoured 215 00:18:32,600 --> 00:18:36,656 when I tell you that our ancient ancestors shared significant 216 00:18:36,680 --> 00:18:40,536 similarities with creatures like this rat. 217 00:18:40,560 --> 00:18:44,496 So what was it that they had that the dinosaurs didn't? 218 00:18:44,520 --> 00:18:47,056 Well, many of the dinosaurs were quite specialised. 219 00:18:47,080 --> 00:18:50,936 The herbivores required very particular species of plants to eat, 220 00:18:50,960 --> 00:18:53,256 the carnivores very particular species of dinosaurs. 221 00:18:53,280 --> 00:18:56,456 But most of the early mammals, they were generalists 222 00:18:56,480 --> 00:18:59,376 and, equally importantly, they were omnivores. 223 00:18:59,400 --> 00:19:02,216 They could eat plant material and flesh. 224 00:19:02,240 --> 00:19:04,856 In fact, they could eat rotting plant material 225 00:19:04,880 --> 00:19:07,496 and rotting flesh, and that was a real asset 226 00:19:07,520 --> 00:19:11,400 when all of that starvation was going on during the impact winter. 227 00:19:12,440 --> 00:19:15,976 So, I have to tell you, that, all of those millions of years ago, 228 00:19:16,000 --> 00:19:20,216 animals like this represented hope. 229 00:19:20,240 --> 00:19:24,376 And the world that we know today was resting on the shoulders 230 00:19:24,400 --> 00:19:26,656 of creatures just like this rat. 231 00:19:26,680 --> 00:19:28,120 I like that. 232 00:19:29,520 --> 00:19:31,400 Yes, down to you! 233 00:19:43,200 --> 00:19:45,576 It's thought the extreme cold conditions 234 00:19:45,600 --> 00:19:48,440 lasted for more than ten years. 235 00:19:54,560 --> 00:19:58,656 But eventually the sky cleared, 236 00:19:58,680 --> 00:20:01,696 the sun shone down 237 00:20:01,720 --> 00:20:05,080 and life could begin to make a recovery. 238 00:20:14,560 --> 00:20:17,296 For more than 150 million years, 239 00:20:17,320 --> 00:20:22,000 the mammals had been living in the shadows of the dinosaurs. 240 00:20:33,960 --> 00:20:37,280 But now a new chapter could begin. 241 00:20:43,400 --> 00:20:45,920 The age of mammals. 242 00:20:51,760 --> 00:20:54,656 And it would be Earth's geological forces, 243 00:20:54,680 --> 00:20:59,000 rather than an asteroid, that would change the course of life. 244 00:21:16,120 --> 00:21:18,576 Deep within the North Atlantic Ocean, 245 00:21:18,600 --> 00:21:21,896 thousands of hydrothermal vents begin to release 246 00:21:21,920 --> 00:21:25,656 vast quantities of greenhouse gases, 247 00:21:25,680 --> 00:21:29,416 including methane, 248 00:21:29,440 --> 00:21:35,200 a gas around 25 times more potent than carbon dioxide. 249 00:21:39,280 --> 00:21:41,536 THUNDERCLAP 250 00:21:41,560 --> 00:21:45,976 This methane escapes into the atmosphere, 251 00:21:46,000 --> 00:21:50,560 sending temperatures rocketing and triggering rapid climate change. 252 00:21:52,920 --> 00:21:57,120 Violent storms ravage the planet with flash floods... 253 00:22:01,320 --> 00:22:03,320 ..and protracted droughts. 254 00:22:07,080 --> 00:22:11,336 This dramatic global warming has profound implications 255 00:22:11,360 --> 00:22:13,400 for the ancient mammals. 256 00:22:18,320 --> 00:22:20,880 BIRDS TWITTER 257 00:22:33,600 --> 00:22:34,640 Look. 258 00:22:36,280 --> 00:22:38,656 Millions of bats. 259 00:22:38,680 --> 00:22:41,240 Millions of mammals. 260 00:22:46,400 --> 00:22:49,016 I can smell them, I can see them, 261 00:22:49,040 --> 00:22:51,896 I can hear them and I can feel them. 262 00:22:51,920 --> 00:22:54,656 There are so many bats out there whirling around 263 00:22:54,680 --> 00:22:56,936 that it's actually generated a breeze, 264 00:22:56,960 --> 00:22:59,480 which is very pleasant given how sweaty I am. 265 00:23:04,600 --> 00:23:07,296 And it's ironic, isn't it, that, just when the planet 266 00:23:07,320 --> 00:23:09,816 was going to see the rise of mammals, 267 00:23:09,840 --> 00:23:13,216 which would ultimately give rise to species like our own, 268 00:23:13,240 --> 00:23:16,696 it was also going through what can only be described as 269 00:23:16,720 --> 00:23:18,856 rapid climate change? 270 00:23:18,880 --> 00:23:22,176 And I can show you that here with this graph. 271 00:23:22,200 --> 00:23:25,616 Now, the Earth was already a few degrees warmer at this time, 272 00:23:25,640 --> 00:23:27,456 but look at this spike. 273 00:23:27,480 --> 00:23:30,096 What this tells us is that, within the space of just 274 00:23:30,120 --> 00:23:34,896 a few thousand years, the global average temperature rose 275 00:23:34,920 --> 00:23:37,096 by five degrees Centigrade. 276 00:23:37,120 --> 00:23:40,936 Incredible but sobering, 277 00:23:40,960 --> 00:23:44,736 because climate scientists today go back through the geological record 278 00:23:44,760 --> 00:23:47,536 and they use this spike as an analogue 279 00:23:47,560 --> 00:23:51,240 for what might be happening to our atmosphere today. 280 00:23:52,360 --> 00:23:56,096 And what really concerns them is how this happened. 281 00:23:56,120 --> 00:24:00,016 What's scary is that it was precipitated by a series of events, 282 00:24:00,040 --> 00:24:03,376 each triggering the next, triggering the next, triggering the next, 283 00:24:03,400 --> 00:24:08,576 until it pushed the Earth past some serious tipping points. 284 00:24:08,600 --> 00:24:11,360 And that is our nightmare. 285 00:24:16,560 --> 00:24:20,216 Scientists believe that 56 million years ago 286 00:24:20,240 --> 00:24:24,840 the hot conditions on Earth led to a very different world. 287 00:24:27,760 --> 00:24:33,456 In the Arctic, where temperatures averaged around 23 degrees, 288 00:24:33,480 --> 00:24:37,760 alligators could be found swimming under palm trees. 289 00:24:39,880 --> 00:24:43,776 But despite this havoc, this hothouse Earth 290 00:24:43,800 --> 00:24:46,400 seems to have had a silver lining. 291 00:24:50,800 --> 00:24:53,856 Because, thanks to the warmer conditions, 292 00:24:53,880 --> 00:24:59,536 subtropical forest or jungle has moved away from the equator 293 00:24:59,560 --> 00:25:04,400 and expanded across much of North America, Europe and Asia. 294 00:25:09,000 --> 00:25:13,736 And this rich, lush habitat would prove to be crucial 295 00:25:13,760 --> 00:25:17,920 to the emergence of new species of mammal. 296 00:25:19,160 --> 00:25:21,800 Ones more like us. 297 00:25:41,560 --> 00:25:43,496 Wow! 298 00:25:43,520 --> 00:25:45,696 Just look at that. 299 00:25:45,720 --> 00:25:47,360 What a landscape. 300 00:25:48,640 --> 00:25:52,576 This is the Calakmul Biosphere Reserve in Mexico 301 00:25:52,600 --> 00:25:56,136 and, with its 2,700 square miles of forest, 302 00:25:56,160 --> 00:25:59,816 it's one of the largest forest reserves in Mexico 303 00:25:59,840 --> 00:26:01,936 and Latin America. 304 00:26:01,960 --> 00:26:05,336 And aside from these Mayan ruins on which I'm standing 305 00:26:05,360 --> 00:26:08,656 and a few other pockets of development, there's very little 306 00:26:08,680 --> 00:26:12,696 human activity here, which means it's packed full of wildlife. 307 00:26:12,720 --> 00:26:15,936 More than 400 species of birds - 308 00:26:15,960 --> 00:26:20,080 toucans, trogons, parrots and tanagers. 309 00:26:22,720 --> 00:26:24,536 And it's not just birds. 310 00:26:24,560 --> 00:26:28,776 Hiding in the forest here are all sorts of other natural wonders - 311 00:26:28,800 --> 00:26:32,216 ocelot, puma, monkeys, 312 00:26:32,240 --> 00:26:34,056 enormous numbers of bats, 313 00:26:34,080 --> 00:26:36,416 not to mention a host of reptiles and amphibians. 314 00:26:36,440 --> 00:26:42,240 So, the question is, why is this place such a biodiversity hot spot? 315 00:26:48,880 --> 00:26:52,456 Now, it's partly due to the vast diversity of plants 316 00:26:52,480 --> 00:26:53,856 that we have here. 317 00:26:53,880 --> 00:26:58,656 We think that in this area alone there are more than 1,500 species. 318 00:26:58,680 --> 00:27:00,336 But it's not just that. 319 00:27:00,360 --> 00:27:03,376 It's also down to something that we very much take for granted. 320 00:27:03,400 --> 00:27:06,696 Have a look at this fossil that I've got here, 321 00:27:06,720 --> 00:27:11,776 and in particular this tiny star-shaped structure. 322 00:27:11,800 --> 00:27:15,696 That is a fossilised flower. 323 00:27:15,720 --> 00:27:19,736 And we know from where this rock came from, in Utah in North America, 324 00:27:19,760 --> 00:27:22,496 that that means that this flower bloomed 325 00:27:22,520 --> 00:27:27,096 around 51 million years ago. 326 00:27:27,120 --> 00:27:29,360 That is incredible. 327 00:27:37,920 --> 00:27:43,360 Flowering plants are one of the great drivers of biodiversity. 328 00:27:46,000 --> 00:27:50,136 And 56 million years ago, Earth's flourishing forests 329 00:27:50,160 --> 00:27:51,840 were full of them. 330 00:27:56,920 --> 00:28:00,816 For insects, flowers offered food in the form of nectar 331 00:28:00,840 --> 00:28:05,280 to tempt them in to spread the plant's pollen for fertilisation. 332 00:28:13,040 --> 00:28:17,960 But for other creatures, there was an even juicier prize. 333 00:28:20,920 --> 00:28:23,896 Something they can eat that helps disperse 334 00:28:23,920 --> 00:28:26,520 the plant's fertilised seeds. 335 00:28:28,360 --> 00:28:32,280 One of the plant kingdom's great gifts to life. 336 00:28:35,080 --> 00:28:36,320 Fruit. 337 00:28:43,600 --> 00:28:47,680 First eaten by birds many tens of millions of years earlier... 338 00:28:49,200 --> 00:28:53,296 ..the fruits of the forest were to play a key role in the 339 00:28:53,320 --> 00:28:58,080 evolution of a new type of mammal revealed in the fossil record. 340 00:29:01,920 --> 00:29:06,336 Fruit offered both a reward and a challenge for mammals. 341 00:29:06,360 --> 00:29:09,656 Now, the reward is that this is a perfectly formed capsule 342 00:29:09,680 --> 00:29:11,776 packed full of calories. 343 00:29:11,800 --> 00:29:14,096 The challenge is you've got to find it 344 00:29:14,120 --> 00:29:17,856 and then you've got to be able to get it, and in a forest environment 345 00:29:17,880 --> 00:29:20,936 like this that's actually quite difficult. 346 00:29:20,960 --> 00:29:23,856 To find it, you've got to be able to see it 347 00:29:23,880 --> 00:29:26,816 and then identify that it's ripe. 348 00:29:26,840 --> 00:29:30,056 And once you've done so, you've got to be able to reach it, 349 00:29:30,080 --> 00:29:33,776 which means that you've got to be able to climb all the way up there, 350 00:29:33,800 --> 00:29:36,856 20, 30 metres or more. 351 00:29:36,880 --> 00:29:40,216 So what creature could have possibly evolved 352 00:29:40,240 --> 00:29:44,360 that could take advantage of this fabulous resource? 353 00:29:46,480 --> 00:29:49,120 Maybe something like that. 354 00:29:51,160 --> 00:29:55,496 And that is a Geoffroy's spider monkey. 355 00:29:55,520 --> 00:29:58,576 Quite a rare animal these days. 356 00:29:58,600 --> 00:30:02,376 But the key thing is that this animal shares significant 357 00:30:02,400 --> 00:30:06,656 characteristics with those first true primates that arose 358 00:30:06,680 --> 00:30:09,720 56 million years ago. 359 00:30:10,720 --> 00:30:13,256 Look at them, they're beautiful, if not a little weird. 360 00:30:13,280 --> 00:30:15,816 They're highly specialised, but look at the head. 361 00:30:15,840 --> 00:30:18,536 Their eyes are forward-facing, like ours, 362 00:30:18,560 --> 00:30:21,776 good for stereoscopic vision, good for spotting fruit. 363 00:30:21,800 --> 00:30:25,016 They've got a relatively big brain, so they can remember where 364 00:30:25,040 --> 00:30:29,216 they previously found that fruit, but the key thing are the limbs. 365 00:30:29,240 --> 00:30:32,616 Look - long and strong. 366 00:30:32,640 --> 00:30:35,216 And if you look very carefully there, 367 00:30:35,240 --> 00:30:38,096 you can see their hands are like hooks. 368 00:30:38,120 --> 00:30:41,296 And their fifth limb, that prehensile tail, 369 00:30:41,320 --> 00:30:43,096 it's so strong they can hang from it 370 00:30:43,120 --> 00:30:45,160 when they're eating fruits like this. 371 00:30:47,160 --> 00:30:51,816 There's no denying that creatures like this are perfectly adapted 372 00:30:51,840 --> 00:30:56,000 for the high life up there at the top of the forest. 373 00:31:04,280 --> 00:31:08,136 Now, we're not entirely sure where the world's first true primates, 374 00:31:08,160 --> 00:31:11,336 our ancestors, appeared because as soon as they evolved 375 00:31:11,360 --> 00:31:14,176 they started spreading rapidly around the world, 376 00:31:14,200 --> 00:31:18,696 between North America and Asia and on into Europe and Africa. 377 00:31:18,720 --> 00:31:22,136 These primates, they were having the time of their lives, 378 00:31:22,160 --> 00:31:25,936 and very rapidly they'd occupied no less than four 379 00:31:25,960 --> 00:31:27,496 of the world's continents. 380 00:31:27,520 --> 00:31:29,576 They were making it look easy and at this point 381 00:31:29,600 --> 00:31:32,816 it seemed as if the Earth was destined to become 382 00:31:32,840 --> 00:31:34,520 a planet of the apes. 383 00:31:39,440 --> 00:31:41,080 But it wasn't to be. 384 00:31:43,520 --> 00:31:47,680 After more than 20 million years of a hothouse Earth... 385 00:31:56,800 --> 00:32:00,200 ..the planet's climate dramatically cooled. 386 00:32:05,560 --> 00:32:10,096 Scientists aren't entirely sure why it happened, 387 00:32:10,120 --> 00:32:12,920 but the result was devastating. 388 00:32:16,840 --> 00:32:18,936 Across the northern continents, 389 00:32:18,960 --> 00:32:22,840 the cooler, drier conditions decimated the jungle. 390 00:32:26,800 --> 00:32:31,240 Destroying much of the habitat of our ancient ancestors. 391 00:32:39,840 --> 00:32:43,696 Sadly, we've been conducting our own perverse experiment 392 00:32:43,720 --> 00:32:47,016 into what happens if you deforest the planet. 393 00:32:47,040 --> 00:32:51,016 This is just one of a multitude of sites all over the world 394 00:32:51,040 --> 00:32:53,056 that have been destroyed. 395 00:32:53,080 --> 00:32:57,256 Until recently, this would have been tropical forest - 396 00:32:57,280 --> 00:33:02,096 lush, green, filled with masses of mammals, 397 00:33:02,120 --> 00:33:05,976 monkeys, tapirs, jaguar. 398 00:33:06,000 --> 00:33:08,776 But they're all gone. 399 00:33:08,800 --> 00:33:11,456 You see, habitat destruction like this 400 00:33:11,480 --> 00:33:16,056 is probably THE leading force when it comes to extinction today, 401 00:33:16,080 --> 00:33:20,696 and it was no different 34 million years ago. 402 00:33:20,720 --> 00:33:24,096 When the tropical forest disappeared from the northern climes, 403 00:33:24,120 --> 00:33:26,776 there were severe consequences. 404 00:33:26,800 --> 00:33:30,536 The primates disappeared from North America completely 405 00:33:30,560 --> 00:33:33,456 and all but disappeared from Europe. 406 00:33:33,480 --> 00:33:37,496 So, on the face of it, this looks like a massive tragedy, 407 00:33:37,520 --> 00:33:41,680 a severe setback for our ancient ancestors. 408 00:33:43,520 --> 00:33:45,376 Or was it? 409 00:33:45,400 --> 00:33:50,416 Because, if the story that we're really telling is the story of us, 410 00:33:50,440 --> 00:33:54,336 Homo sapiens, humans, then it's not that simple. 411 00:33:54,360 --> 00:33:58,296 The path of evolution that would lead from those ancient ancestors 412 00:33:58,320 --> 00:34:03,416 to a creature like us, an upright, bipedal, big-brained ape 413 00:34:03,440 --> 00:34:07,296 with opposing thumbs, was never going to be straight-forward. 414 00:34:07,320 --> 00:34:11,336 For evolution to come up with something like the human species, 415 00:34:11,360 --> 00:34:16,016 it would require a very precise and complex series of events, 416 00:34:16,040 --> 00:34:21,176 and it would need to occur in a very specific environment, 417 00:34:21,200 --> 00:34:27,480 where evolution could be nudged, if you like, towards the human species. 418 00:34:28,520 --> 00:34:33,480 And it would be down to the Earth to create that very special place. 419 00:34:49,560 --> 00:34:53,096 Although primates had mostly disappeared from the cold, 420 00:34:53,120 --> 00:34:55,400 dry, northerly continents... 421 00:35:00,000 --> 00:35:04,176 ..in East Africa, where the jungle still remained, 422 00:35:04,200 --> 00:35:05,880 they had survived. 423 00:35:13,920 --> 00:35:19,240 And here, the planet's forces began to shape a new environment. 424 00:35:23,280 --> 00:35:28,056 From deep within Earth, hot magma started to rise up, 425 00:35:28,080 --> 00:35:33,416 lifting the ground and forming large cracks on the surface 426 00:35:33,440 --> 00:35:37,920 as, over millions of years, the continent pulls apart. 427 00:35:58,000 --> 00:36:02,920 It forms the spectacular East African Rift Valley. 428 00:36:04,720 --> 00:36:09,056 Running some 4,000 miles through what will become 429 00:36:09,080 --> 00:36:14,000 Ethiopia, Kenya, Tanzania and Mozambique. 430 00:36:20,640 --> 00:36:26,176 And crucially, with its patchwork of forests and savannah, 431 00:36:26,200 --> 00:36:29,720 it presents the primates with a dilemma. 432 00:36:31,520 --> 00:36:33,560 ENGINE PUTTERS 433 00:36:47,200 --> 00:36:49,976 So what was the dilemma? 434 00:36:50,000 --> 00:36:52,936 Well, the first thing you have to appreciate is that the 435 00:36:52,960 --> 00:36:56,456 Rift Valley in East Africa was no longer a single, great, 436 00:36:56,480 --> 00:36:58,656 vast tract of tropical forest. 437 00:36:58,680 --> 00:37:02,776 It had become fragmented into smaller pockets of forest, 438 00:37:02,800 --> 00:37:06,936 quite analogous to this rather beautiful park that I'm sat in. 439 00:37:06,960 --> 00:37:11,456 So these represent those pockets of forest and the paths in-between 440 00:37:11,480 --> 00:37:14,736 the grassland that had formed between them. 441 00:37:14,760 --> 00:37:19,136 Now, I want you to imagine that you are a highly arboreal, 442 00:37:19,160 --> 00:37:22,496 tree swinging, fruit eating primate 443 00:37:22,520 --> 00:37:25,536 and you've had your breakfast here at point A, 444 00:37:25,560 --> 00:37:29,400 but your lunch is over there at point B. 445 00:37:30,600 --> 00:37:32,336 How do you get between the two? 446 00:37:32,360 --> 00:37:37,296 Because in the old days you could simply swing from tree to tree. 447 00:37:37,320 --> 00:37:42,080 This was the dilemma facing those early primates. 448 00:37:43,400 --> 00:37:46,896 The forest had fragmented, so had their food supply, 449 00:37:46,920 --> 00:37:51,840 and they had no efficient way of getting from A to B. 450 00:37:53,320 --> 00:37:56,016 So, what was the solution? 451 00:37:56,040 --> 00:37:58,096 What did evolution come up with? 452 00:37:58,120 --> 00:38:01,576 Well, some of those early primates decided to stick it out in the 453 00:38:01,600 --> 00:38:05,416 shrinking forest and they evolved into chimpanzees and gorillas. 454 00:38:05,440 --> 00:38:08,696 But another group, our ancient ancestors, 455 00:38:08,720 --> 00:38:11,616 started to do something that we take for granted 456 00:38:11,640 --> 00:38:14,456 but we have to learn to do. 457 00:38:14,480 --> 00:38:16,216 What do you reckon? 458 00:38:16,240 --> 00:38:19,600 I'll tell you - they started walking on two feet. 459 00:38:33,600 --> 00:38:37,496 But our early ancestors didn't just walk out of the forest 460 00:38:37,520 --> 00:38:40,416 never to return. They still spent a lot of time there, 461 00:38:40,440 --> 00:38:42,176 probably even sleeping in the trees. 462 00:38:42,200 --> 00:38:44,896 But walking gave them freedom 463 00:38:44,920 --> 00:38:48,056 and with that freedom came the ability to hunt, 464 00:38:48,080 --> 00:38:51,856 so they started eating meat and then they evolved bigger brains. 465 00:38:51,880 --> 00:38:54,976 And that's why the Rift Valley in East Africa 466 00:38:55,000 --> 00:38:57,616 is known as the Cradle of Humanity. 467 00:38:57,640 --> 00:39:02,656 Now, initially, there were quite a number of human species. 468 00:39:02,680 --> 00:39:05,816 But the key thing is that that is where our species, 469 00:39:05,840 --> 00:39:07,960 Homo sapiens, evolved. 470 00:39:16,960 --> 00:39:22,160 Now, the origins of our species are still shrouded in mystery. 471 00:39:31,720 --> 00:39:35,136 But the East African Rift Valley is where scientists 472 00:39:35,160 --> 00:39:38,680 have discovered many of the most important fossils... 473 00:39:43,080 --> 00:39:47,000 ..that tell the incredible story of human evolution... 474 00:39:51,000 --> 00:39:54,616 ..and the emergence of Homo sapiens 475 00:39:54,640 --> 00:39:57,680 around 300,000 years ago. 476 00:40:08,520 --> 00:40:12,976 With hindsight, we simply have to marvel at that remarkable 477 00:40:13,000 --> 00:40:17,856 set of factors that came together to produce that highly unlikely 478 00:40:17,880 --> 00:40:19,856 chain of events. 479 00:40:19,880 --> 00:40:23,216 The seemingly impossible had happened. 480 00:40:23,240 --> 00:40:25,976 After the best part of 66 million years, 481 00:40:26,000 --> 00:40:28,936 after continents tearing themselves apart, 482 00:40:28,960 --> 00:40:32,576 mountain ranges forming, the Earth's climate fluxing 483 00:40:32,600 --> 00:40:34,616 and throwing between hot and cold, 484 00:40:34,640 --> 00:40:38,680 a new force was about to be unleashed upon the Earth. 485 00:40:39,960 --> 00:40:43,160 Humans had arrived, and there was no turning back. 486 00:41:19,400 --> 00:41:23,840 Yet whilst our species had been evolving in the warmth of Africa... 487 00:41:25,920 --> 00:41:29,240 ..Earth's climate had continued to cool. 488 00:41:38,840 --> 00:41:42,576 Scientists think that part of the reason may be down to Earth's 489 00:41:42,600 --> 00:41:45,256 new mountain ranges - 490 00:41:45,280 --> 00:41:48,480 the Himalayas, Andes and Rockies. 491 00:41:50,400 --> 00:41:53,496 They had formed over tens of millions of years 492 00:41:53,520 --> 00:41:59,480 as the result of plate tectonics pushing up the Earth's crust. 493 00:42:01,360 --> 00:42:03,776 And through the process of weathering, 494 00:42:03,800 --> 00:42:07,416 the exposed rock was reacting with carbon dioxide, 495 00:42:07,440 --> 00:42:11,800 removing it from the air and causing temperatures to drop. 496 00:42:22,240 --> 00:42:27,376 It meant that, as humans migrated out of Africa into Europe, 497 00:42:27,400 --> 00:42:32,936 Asia and Australia, the extreme cold, dry conditions 498 00:42:32,960 --> 00:42:36,960 prevented them from crossing into North America. 499 00:42:42,480 --> 00:42:46,240 Earth was in the midst of an Ice Age. 500 00:43:03,120 --> 00:43:06,136 And yet, despite the extreme challenges 501 00:43:06,160 --> 00:43:11,816 we faced from the climate, it was around this time that humans 502 00:43:11,840 --> 00:43:16,960 began to create something that had never existed on Earth before. 503 00:43:22,400 --> 00:43:23,920 Art. 504 00:43:30,200 --> 00:43:35,616 The oldest that we know of is this painting of a pig in Indonesia, 505 00:43:35,640 --> 00:43:40,160 and it's been dated to around 45,000 years ago. 506 00:43:53,520 --> 00:43:55,696 And closer to home in Europe, 507 00:43:55,720 --> 00:43:59,200 we find cave paintings from more recent periods. 508 00:44:08,440 --> 00:44:11,736 Here we are, back in this spectacular cave 509 00:44:11,760 --> 00:44:13,696 with its remarkable drawings. 510 00:44:13,720 --> 00:44:18,296 They are so, so beautiful that it's worth taking a moment 511 00:44:18,320 --> 00:44:20,496 to think about what's going on here. 512 00:44:20,520 --> 00:44:24,736 Well, around 13,000 years ago, 513 00:44:24,760 --> 00:44:28,776 humans of the same species, exactly the same species as us, 514 00:44:28,800 --> 00:44:34,256 were standing or crouching here in the flickering light of their lamps, 515 00:44:34,280 --> 00:44:39,416 making these beautiful, beautiful drawings. 516 00:44:39,440 --> 00:44:41,736 But what's it about? 517 00:44:41,760 --> 00:44:44,976 Well, art is always about communication. 518 00:44:45,000 --> 00:44:49,096 And this isn't just communicating to me about their intelligence 519 00:44:49,120 --> 00:44:52,896 or their creativity - there's something else going on. 520 00:44:52,920 --> 00:44:57,216 And it's interesting to note that in cave paintings of this age 521 00:44:57,240 --> 00:45:00,256 humans are very rarely depicted. 522 00:45:00,280 --> 00:45:03,856 It's always about nature. 523 00:45:03,880 --> 00:45:08,616 And at this time, all of these species were wild animals. 524 00:45:08,640 --> 00:45:13,176 We were still hunter gatherers, we were in tune with, 525 00:45:13,200 --> 00:45:17,520 connected to and, critically, part of nature. 526 00:45:18,680 --> 00:45:22,776 But for us to go on to become the global force that we've become, 527 00:45:22,800 --> 00:45:25,256 things would need to change. 528 00:45:25,280 --> 00:45:28,216 Our population would have to grow massively 529 00:45:28,240 --> 00:45:32,920 and to achieve that we would need to control nature. 530 00:45:47,480 --> 00:45:51,056 The extreme cold and dry conditions of the Ice Age 531 00:45:51,080 --> 00:45:53,440 were not destined to last. 532 00:45:55,560 --> 00:45:59,616 Subtle changes in Earth's orbit altered the amount of sunlight 533 00:45:59,640 --> 00:46:01,400 reaching the planet's surface. 534 00:46:02,800 --> 00:46:06,536 And together with increasing levels of carbon dioxide, 535 00:46:06,560 --> 00:46:09,280 this pushed up temperatures... 536 00:46:13,440 --> 00:46:15,600 ..melting the ice. 537 00:46:24,640 --> 00:46:29,440 For the first time, humans spread across North and South America. 538 00:46:31,520 --> 00:46:36,240 We were now living on every continent except Antarctica. 539 00:46:46,240 --> 00:46:49,056 And it was around 11,000 years ago, 540 00:46:49,080 --> 00:46:52,296 in this warmer and more humid climate, 541 00:46:52,320 --> 00:46:56,920 that humans did something simple but revolutionary. 542 00:46:58,680 --> 00:47:01,256 They began to farm, 543 00:47:01,280 --> 00:47:05,280 first growing crops, then raising livestock. 544 00:47:07,000 --> 00:47:08,896 Within a few thousand years, 545 00:47:08,920 --> 00:47:13,480 nearly all human societies on the planet were farming. 546 00:47:17,680 --> 00:47:20,456 And slowly but surely, 547 00:47:20,480 --> 00:47:25,216 producing food became an industrialised process 548 00:47:25,240 --> 00:47:29,600 with an ever greater impact on Earth's ecosystems. 549 00:47:48,560 --> 00:47:53,016 This is a vast field of soya beans, 550 00:47:53,040 --> 00:47:57,296 stretching all the way to the horizon where the forest remains. 551 00:47:57,320 --> 00:48:00,896 And many people think of this as a natural environment, 552 00:48:00,920 --> 00:48:04,456 but it couldn't be further from natural if it tried. 553 00:48:04,480 --> 00:48:08,336 This is the antithesis of biodiversity. 554 00:48:08,360 --> 00:48:11,776 Now, imagine biodiversity is a rainbow 555 00:48:11,800 --> 00:48:16,176 and the spectrum represents the full breadth of beautiful life 556 00:48:16,200 --> 00:48:18,376 and when we're looking at this 557 00:48:18,400 --> 00:48:21,536 we're looking at a tiny slice of one colour. 558 00:48:21,560 --> 00:48:26,616 All of these regimented rows here are just one species. 559 00:48:26,640 --> 00:48:28,560 This is a monoculture. 560 00:48:29,960 --> 00:48:33,776 And it's not just that because the conditions that this crop 561 00:48:33,800 --> 00:48:36,416 require to grow weren't here naturally. 562 00:48:36,440 --> 00:48:40,176 This has been flattened, it's been drained, it's been fertilised. 563 00:48:40,200 --> 00:48:43,880 It's been smothered in pesticides to keep nature out. 564 00:48:45,880 --> 00:48:48,656 Now, forgive me, because for just a moment 565 00:48:48,680 --> 00:48:51,616 I'm going to take on the difficult role of devil's advocate. 566 00:48:51,640 --> 00:48:55,136 Imagine that we could put all of those environmental issues 567 00:48:55,160 --> 00:48:57,560 to one side and take a fresh look at this. 568 00:49:03,800 --> 00:49:06,776 We might consider it to be remarkable 569 00:49:06,800 --> 00:49:11,176 because it's highly efficient crop production like this 570 00:49:11,200 --> 00:49:14,256 which is producing enough food to cater 571 00:49:14,280 --> 00:49:18,296 for our ever increasing human population. 572 00:49:18,320 --> 00:49:22,736 You might say that our ability to invent technologies 573 00:49:22,760 --> 00:49:26,496 and come up with a food production system that can feed 574 00:49:26,520 --> 00:49:29,816 around eight billion people and keep many of them 575 00:49:29,840 --> 00:49:34,640 out of starvation and famine is an incredible achievement. 576 00:49:36,160 --> 00:49:38,896 But I can't forget those environmental issues, 577 00:49:38,920 --> 00:49:42,336 certainly when I tell you that 40% 578 00:49:42,360 --> 00:49:46,416 of the world's land surface that isn't frozen 579 00:49:46,440 --> 00:49:50,496 is now given over to agriculture like this - 580 00:49:50,520 --> 00:49:54,816 bland monocultures devoid of life. 581 00:49:54,840 --> 00:50:00,496 And also, I can tell you that, of all the mammals alive at this point 582 00:50:00,520 --> 00:50:02,416 on planet Earth today, 583 00:50:02,440 --> 00:50:06,496 only 4% of them are wild animals. 584 00:50:06,520 --> 00:50:10,936 96% are humans, their pets 585 00:50:10,960 --> 00:50:12,920 or domestic farm animals. 586 00:50:14,840 --> 00:50:19,080 And that, from my perspective, is terrifying. 587 00:50:29,360 --> 00:50:32,016 But our takeover of the natural world 588 00:50:32,040 --> 00:50:34,360 goes far beyond industrial agriculture. 589 00:50:39,320 --> 00:50:43,456 Humans now have a greater effect in shaping the Earth's surface 590 00:50:43,480 --> 00:50:45,760 than many natural processes. 591 00:50:49,640 --> 00:50:53,616 And human-made materials, like concrete and plastic, 592 00:50:53,640 --> 00:50:59,360 outweigh the combined biomass of all life on the planet. 593 00:51:02,800 --> 00:51:08,216 Behind all of this is the staggering increase in the human population. 594 00:51:08,240 --> 00:51:11,560 From one billion just a couple of hundred years ago... 595 00:51:13,720 --> 00:51:16,240 ..to eight billion today. 596 00:51:36,360 --> 00:51:39,440 Welcome to the human planet. 597 00:51:40,560 --> 00:51:45,816 Now, it is awesome but for me it's not wondrous 598 00:51:45,840 --> 00:51:49,240 because, hand on heart, this is not my sort of environment. 599 00:51:50,440 --> 00:51:53,056 I mean, there is some nature here, 600 00:51:53,080 --> 00:51:56,096 but most of it is entirely artificial. 601 00:51:56,120 --> 00:52:01,640 Most of what I can see is made of brick, concrete, steel and glass. 602 00:52:03,360 --> 00:52:06,016 This is Mexico City, 603 00:52:06,040 --> 00:52:10,856 and together with the 59 districts that radiate out to the horizon 604 00:52:10,880 --> 00:52:15,056 it occupies 3,000 square miles, 605 00:52:15,080 --> 00:52:18,880 and it's home to more than 21 million people. 606 00:52:20,080 --> 00:52:22,536 And, staggeringly, it's not unique. 607 00:52:22,560 --> 00:52:26,496 There are more than 30 other megacities across the world 608 00:52:26,520 --> 00:52:28,960 with more than ten million people living in them. 609 00:52:30,880 --> 00:52:35,896 But standing here looking at all of this you've got to ask, 610 00:52:35,920 --> 00:52:38,696 "How can it possibly work?" 611 00:52:38,720 --> 00:52:41,616 One thing that we have to acknowledge 612 00:52:41,640 --> 00:52:44,096 is that agricultural revolution, 613 00:52:44,120 --> 00:52:47,976 our ability to produce food with brutal efficiency. 614 00:52:48,000 --> 00:52:52,280 That's what feeds all of us living in these megacities. 615 00:52:53,440 --> 00:52:57,336 But there's another far more important ingredient, 616 00:52:57,360 --> 00:53:00,856 something that was formed by the Earth and life 617 00:53:00,880 --> 00:53:02,816 hundreds of millions of years ago, 618 00:53:02,840 --> 00:53:06,920 something that we've drilled for and mined for. 619 00:53:08,080 --> 00:53:11,496 I'm talking about coal, oil and gas - 620 00:53:11,520 --> 00:53:13,400 the fossil fuels. 621 00:53:15,000 --> 00:53:17,496 That's what's powered the technology that's allowed us 622 00:53:17,520 --> 00:53:20,776 to build these megacities. 623 00:53:20,800 --> 00:53:23,336 But it comes at a terrible cost 624 00:53:23,360 --> 00:53:26,216 because, as we continue to burn those fossil fuels, 625 00:53:26,240 --> 00:53:29,896 we are pumping CO2 into this atmosphere 626 00:53:29,920 --> 00:53:33,616 at a rate that's comparable with some of those volcanic eruptions 627 00:53:33,640 --> 00:53:36,040 that occurred millions of years ago. 628 00:53:37,760 --> 00:53:39,280 And critically... 629 00:53:41,240 --> 00:53:46,160 ..we've started to radically transform our climate. 630 00:53:58,120 --> 00:54:04,096 For most of Earth's 4.5 billion year history, 631 00:54:04,120 --> 00:54:06,920 the most dramatic changes in climate... 632 00:54:10,640 --> 00:54:13,440 ..have been driven by asteroids... 633 00:54:15,160 --> 00:54:17,120 LOUD BLAST 634 00:54:21,240 --> 00:54:23,600 LOUD RUMBLING 635 00:54:25,680 --> 00:54:29,320 ..the powerful tectonic movement of the continents... 636 00:54:38,080 --> 00:54:42,296 ..and the catastrophic eruptions of volcanoes. 637 00:54:42,320 --> 00:54:45,160 BOOMING EXPLOSION 638 00:55:04,400 --> 00:55:07,496 Of course, as we've seen, 639 00:55:07,520 --> 00:55:12,880 there have been moments when life too has had a profound impact. 640 00:55:18,800 --> 00:55:26,280 Like the bacteria that colonised the oceans 2.4 billion years ago... 641 00:55:28,400 --> 00:55:32,360 ..and gave us the oxygen we breathe. 642 00:55:36,960 --> 00:55:42,496 Or the swamp forests that sent temperatures spiralling downwards 643 00:55:42,520 --> 00:55:46,520 and created the coal we now burn. 644 00:55:53,920 --> 00:55:59,360 But today, the climate is changing at a faster rate... 645 00:56:00,960 --> 00:56:06,040 ..than at any time in the last 66 million years. 646 00:56:12,560 --> 00:56:16,736 Now, I've seen so much of the natural world that I cherish 647 00:56:16,760 --> 00:56:19,896 destroyed that it's difficult not to be pessimistic. 648 00:56:19,920 --> 00:56:23,216 But, ironically, when I go searching for hope, 649 00:56:23,240 --> 00:56:27,016 I don't turn to those planetary forces. 650 00:56:27,040 --> 00:56:30,856 I turn to the power of humanity 651 00:56:30,880 --> 00:56:34,776 because, for all of our flaws, all of our foolishness, 652 00:56:34,800 --> 00:56:38,560 we are a truly remarkable species. 653 00:56:40,000 --> 00:56:42,296 Adaptable, resourceful, 654 00:56:42,320 --> 00:56:45,240 inventive, intelligent, creative. 655 00:56:46,280 --> 00:56:50,336 And you might argue that our most significant turning points 656 00:56:50,360 --> 00:56:54,056 were perhaps standing up on two legs and beginning to walk 657 00:56:54,080 --> 00:56:58,096 or drawing those animals on the cave walls or inventing farming, 658 00:56:58,120 --> 00:57:00,080 or even landing on the moon. 659 00:57:01,480 --> 00:57:07,216 But I need to argue that these were just our dress rehearsals, 660 00:57:07,240 --> 00:57:11,416 because in the very near future our species will need to reach 661 00:57:11,440 --> 00:57:16,856 the zenith of its achievements and that all humanity will have to learn 662 00:57:16,880 --> 00:57:20,520 to put our Earth first. 663 00:57:22,160 --> 00:57:27,496 That unique, fragile, beautiful Earth 664 00:57:27,520 --> 00:57:32,576 that for more than four billion years has been forming this stage 665 00:57:32,600 --> 00:57:34,656 on which we now stand, 666 00:57:34,680 --> 00:57:38,080 and it's waiting for our finest performance. 667 00:57:39,640 --> 00:57:41,656 And if we don't pull it off, 668 00:57:41,680 --> 00:57:46,416 then of course life on this planet will continue to prosper. 669 00:57:46,440 --> 00:57:50,000 But there will be no encore for humanity. 670 00:58:23,920 --> 00:58:27,176 If the Earth could talk, what would it tell us? 671 00:58:27,200 --> 00:58:29,856 Well, the Open University imagine how it might answer 672 00:58:29,880 --> 00:58:31,336 some of our questions. 673 00:58:31,360 --> 00:58:34,016 To experience this interactive presentation, 674 00:58:34,040 --> 00:58:35,696 go to the website on the screen 675 00:58:35,720 --> 00:58:38,040 and follow the links to the Open University. 676 00:58:38,090 --> 00:58:42,640 Repair and Synchronization by Easy Subtitles Synchronizer 1.0.0.0 56636

Can't find what you're looking for?
Get subtitles in any language from opensubtitles.com, and translate them here.