1
00:00:07,007 --> 00:00:09,009
[wind whistling]

2
00:00:13,596 --> 00:00:16,516
[Morgan Freeman] 252 million years ago…

3
00:00:18,685 --> 00:00:21,813
and our planet is dying.

4
00:00:22,605 --> 00:00:24,607
[haunting music playing]

5
00:00:30,488 --> 00:00:36,244
The biggest extinction event in history
has left the world barren…

6
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and deathly silent.

7
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[music intensifies]

8
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But this is the story of the few…

9
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[snorts, panting]

10
00:01:03,980 --> 00:01:05,273
…that survived.

11
00:01:06,274 --> 00:01:07,942
[music fades]

12
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[rousing music playing]

13
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[snarling]

14
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[trilling]

15
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[screeching]

16
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[rousing music continues]

17
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[growling]

18
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[wind howling]

19
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[rumbling]

20
00:02:00,829 --> 00:02:02,997
[rousing music intensifies]

21
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[music fades]

22
00:02:35,738 --> 00:02:38,575
The start of the Triassic Period…

23
00:02:41,244 --> 00:02:45,331
and the rivers of fire
are gradually subsiding.

24
00:02:50,795 --> 00:02:51,880
In their wake,

25
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cooling lava covers an area
half the size of the United States…

26
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[wind whistling]

27
00:03:01,264 --> 00:03:05,018
…in a crust up to three kilometers deep.

28
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[melancholic music playing]

29
00:03:10,106 --> 00:03:15,904
Volcanic gases have caused
global temperatures to soar.

30
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Forests and reefs

31
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have been annihilated.

32
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Hundreds of millions of years
of evolution,

33
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gone.

34
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Yet here,

35
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hidden in the blackened landscape…

36
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lies opportunity.

37
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For there is one particular life-form
that thrives on dead organic matter.

38
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Fungi.

39
00:04:28,935 --> 00:04:32,230
With the world an apocalyptic graveyard,

40
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fungi were in their element.

41
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And for a few thousand years…

42
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these simple organisms

43
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became the dominant life-form on Earth.

44
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But not every survivor
of the Permian extinction

45
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relied on death for their success.

46
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One lowly creature

47
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found itself perfectly placed

48
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to take over the world.

49
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[purring]

50
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[breathes gently]

51
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[exhales]

52
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Lystrosaurus…

53
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[yawns]

54
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…an ancient ancestor of the mammal.

55
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This curious, pig-sized creature

56
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was used to burrowing underground

57
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and seeking refuge in caves,

58
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a way of life that saved it

59
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when other animals were dying.

60
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[bellows]

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Once hapless underdogs,

62
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they are now one of the few
lucky survivors of Armageddon.

63
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With most vegetation destroyed
by the extinction,

64
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finding food is hard.

65
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[snuffling]

66
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But Lystrosaurus are resilient

67
00:07:00,002 --> 00:07:02,880
and able to forage over large areas.

68
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[stirring music playing]

69
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They're constantly on the move,

70
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searching for roots, tubers,
and small pockets of regrowth.

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[snuffling, grunting]

72
00:07:55,641 --> 00:07:58,019
But they weren't
the only animal survivors.

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[sniffs]

74
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[grunts]

75
00:08:02,857 --> 00:08:05,735
Life in many forms

76
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found a way.

77
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[bellowing]

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Lystrosaurus's simple
but adaptable lifestyle

79
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would reap astonishing rewards.

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Facing little competition
and no large predators,

81
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the volcanic eruptions turned it
from a bottom-of-the-food-chain burrower…

82
00:08:33,054 --> 00:08:35,056
[snuffling, bellowing]

83
00:08:36,474 --> 00:08:39,894
…to the animal that inherited the Earth.

84
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[uplifting music playing]

85
00:08:53,533 --> 00:08:56,202
In the years following
the mass extinction,

86
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they made up three-quarters
of all vertebrate life on land,

87
00:09:05,253 --> 00:09:09,006
something no other animal has ever done.

88
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[bellowing]

89
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But their dominance couldn't last,

90
00:09:21,602 --> 00:09:24,730
for another survivor
of the mass extinction

91
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was on the ascent

92
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thanks to huge changes
to the very structure of our planet.

93
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[music ends]

94
00:09:38,786 --> 00:09:41,455
For tens of millions of years,

95
00:09:41,539 --> 00:09:44,625
the Earth's continents
had been converging,

96
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creating a vast ocean
on one side of the world…

97
00:09:52,800 --> 00:09:56,637
and a single immense land mass
on the other,

98
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the supercontinent of Pangaea.

99
00:10:01,434 --> 00:10:03,436
[intriguing music playing]

100
00:10:16,824 --> 00:10:19,577
The drying that started in a previous era

101
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is now compounded by searing heat.

102
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[wind whistling]

103
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Temperatures spike to 60 degrees Celsius.

104
00:10:50,941 --> 00:10:53,778
Sandstorms scour the interior.

105
00:10:59,367 --> 00:11:02,745
Dunes rise over a kilometer high…

106
00:11:15,341 --> 00:11:19,679
gradually forming the largest
and most hostile desert

107
00:11:19,762 --> 00:11:21,639
the planet has ever seen.

108
00:11:28,312 --> 00:11:30,314
[music fades]

109
00:11:30,398 --> 00:11:34,944
Yet on the margins
of this barren and lifeless landscape,

110
00:11:35,945 --> 00:11:39,365
another group of survivors
was on the rise.

111
00:11:47,832 --> 00:11:51,836
And they still dominate our deserts today.

112
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[pensive music playing]

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This is the Atacama in South America.

114
00:12:12,690 --> 00:12:16,694
It's been a desert here
since the Triassic Period.

115
00:12:18,988 --> 00:12:22,992
Some parts have gone decades
without a drop of rain,

116
00:12:24,410 --> 00:12:27,872
yet one type of animal thrives here.

117
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Lizards.

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They're reptiles, supremely adapted
to this dry environment.

119
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They have tough, scaly skin

120
00:12:50,936 --> 00:12:53,522
so they don't shrivel in the baking sun.

121
00:12:56,442 --> 00:12:59,820
Instead, the sun fuels them…

122
00:13:04,241 --> 00:13:08,788
heating their cold blood
so they can reach racing speeds.

123
00:13:15,669 --> 00:13:20,508
But even desert reptiles
need to quench their thirst.

124
00:13:29,308 --> 00:13:32,895
Water seeping up through the ground.

125
00:13:38,317 --> 00:13:44,365
Unfortunately, these water holes
are almost as salty as the Dead Sea.

126
00:13:46,617 --> 00:13:48,619
[flies buzz]

127
00:13:50,162 --> 00:13:53,165
Drinking this would be a death sentence…

128
00:13:55,125 --> 00:13:59,463
so these lizards get their water
from an unexpected source,

129
00:14:00,297 --> 00:14:04,134
an animal whose ancestors
also survived Armageddon.

130
00:14:08,472 --> 00:14:11,308
Insects were hit hard
in the mass extinction,

131
00:14:12,101 --> 00:14:14,395
but some made it through.

132
00:14:16,355 --> 00:14:20,776
Today, these brine flies
are salt specialists,

133
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desalinating the water,

134
00:14:24,488 --> 00:14:29,994
and in the process, making themselves
into perfect little water bottles

135
00:14:30,786 --> 00:14:31,871
for lizards.

136
00:14:38,043 --> 00:14:39,920
[buzzing]

137
00:14:41,130 --> 00:14:44,592
The challenge is catching them.

138
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[playful music playing]

139
00:14:52,099 --> 00:14:53,934
[buzzing]

140
00:15:10,117 --> 00:15:11,243
Finally.

141
00:15:21,921 --> 00:15:23,047
[buzzing]

142
00:15:28,719 --> 00:15:31,347
But just when it thinks it's cracked it,

143
00:15:32,431 --> 00:15:34,558
trouble on the horizon.

144
00:15:37,853 --> 00:15:42,441
These prime fly-catching spots
are in high demand…

145
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[tense music playing]

146
00:15:49,031 --> 00:15:53,035
…and the locals do not like to share.

147
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[energetic music playing]

148
00:16:41,291 --> 00:16:43,168
[music ends]

149
00:16:43,252 --> 00:16:44,294
A stalemate,

150
00:16:45,254 --> 00:16:47,423
but on another lizard's territory.

151
00:16:48,132 --> 00:16:50,092
[energetic music resumes]

152
00:17:04,148 --> 00:17:06,150
-[water splashing]
-[music ends]

153
00:17:06,900 --> 00:17:08,902
[buzzing]

154
00:17:11,071 --> 00:17:13,073
[peaceful music playing]

155
00:17:14,616 --> 00:17:16,952
[flies buzzing]

156
00:17:20,956 --> 00:17:22,875
The thirsty lizard seizes the moment…

157
00:17:25,335 --> 00:17:27,796
making the most of their distraction…

158
00:17:32,092 --> 00:17:33,510
no matter how brief.

159
00:17:39,516 --> 00:17:42,102
The ultimate desert dwellers,

160
00:17:42,186 --> 00:17:45,105
lizards are tough and resilient,

161
00:17:46,273 --> 00:17:48,776
just like their ancient ancestors.

162
00:17:54,198 --> 00:17:58,660
But back in the Triassic,
it was much larger reptiles

163
00:17:59,244 --> 00:18:01,789
who would change the course of history.

164
00:18:05,793 --> 00:18:09,463
In the four million years
since the Permian extinction…

165
00:18:09,546 --> 00:18:10,506
[grunts]

166
00:18:10,589 --> 00:18:13,217
…Lystrosaurus have dominated.

167
00:18:17,846 --> 00:18:21,141
They emerged into an almost empty world

168
00:18:23,018 --> 00:18:25,687
and have been reaping the rewards.

169
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[mewling]

170
00:18:31,276 --> 00:18:33,987
Life is good.

171
00:18:34,071 --> 00:18:36,073
[carefree music playing]

172
00:18:40,035 --> 00:18:41,662
-[adult purrs]
-[juvenile grunts]

173
00:18:46,291 --> 00:18:48,252
[playful calling]

174
00:18:50,087 --> 00:18:52,798
But these mammal ancestors

175
00:18:53,924 --> 00:18:57,511
have had little competition or predators,

176
00:18:58,929 --> 00:19:00,097
until now.

177
00:19:01,473 --> 00:19:03,183
[growling]

178
00:19:05,144 --> 00:19:07,437
[sinister music playing]

179
00:19:07,521 --> 00:19:09,523
[growls]

180
00:19:20,075 --> 00:19:21,910
With the planet recovering,

181
00:19:22,828 --> 00:19:26,331
some reptiles have grown
to epic proportions.

182
00:19:36,675 --> 00:19:38,927
This is an Erythrosuchid.

183
00:19:39,011 --> 00:19:40,929
[snarling]

184
00:19:41,013 --> 00:19:46,810
Nearly three meters long,
it's the biggest predator of its time.

185
00:19:49,313 --> 00:19:51,315
[purring]

186
00:19:52,149 --> 00:19:55,819
Herds of Lystrosaurus are an easy target.

187
00:19:57,279 --> 00:19:58,739
[mewling]

188
00:19:59,740 --> 00:20:01,742
[grunting, snarling]

189
00:20:02,701 --> 00:20:04,703
[tense music playing]

190
00:20:10,334 --> 00:20:14,338
They have no defense
against this new type of reptile…

191
00:20:18,342 --> 00:20:22,137
or even awareness of the threat it poses.

192
00:20:23,889 --> 00:20:25,140
[snarls]

193
00:20:27,601 --> 00:20:28,602
[snorts]

194
00:20:32,481 --> 00:20:33,482
[mewls]

195
00:20:38,278 --> 00:20:39,404
[squeals]

196
00:20:41,031 --> 00:20:42,491
[snarls]

197
00:20:45,244 --> 00:20:47,287
Like a fox in a chicken coop,

198
00:20:47,371 --> 00:20:51,083
an Erythrosuchid
can kill more than it needs.

199
00:20:54,753 --> 00:20:56,338
-[faint cry]
-[snarling]

200
00:21:03,720 --> 00:21:07,057
Lystrosaurus was the unwitting dodo…

201
00:21:07,724 --> 00:21:09,142
-[snarls]
-[squeals]

202
00:21:09,226 --> 00:21:10,519
…of its age.

203
00:21:17,192 --> 00:21:20,529
A combination
of predators and competition

204
00:21:21,571 --> 00:21:25,659
saw Lystrosaurus go
from total domination of the planet

205
00:21:27,577 --> 00:21:28,787
to extinction.

206
00:21:28,870 --> 00:21:30,872
[mournful music playing]

207
00:21:31,915 --> 00:21:35,168
The mammals had lost their crown.

208
00:21:38,880 --> 00:21:39,923
This…

209
00:21:40,007 --> 00:21:42,718
[snarling]

210
00:21:42,801 --> 00:21:46,013
…was the age of reptiles.

211
00:22:06,742 --> 00:22:12,748
Today, there are more
than 10,000 species of reptile…

212
00:22:15,000 --> 00:22:19,296
although they are not all as terrifying
as their ancestors.

213
00:22:26,720 --> 00:22:28,889
As the Earth has changed…

214
00:22:28,972 --> 00:22:30,766
[uplifting music playing]

215
00:22:30,849 --> 00:22:35,437
…reptiles have had to adapt
to an ever more crowded world.

216
00:22:39,232 --> 00:22:41,109
And the tough, scaly skin

217
00:22:41,777 --> 00:22:44,613
that allowed them to conquer
the deserts of Pangaea,

218
00:22:46,073 --> 00:22:49,910
continues to be the secret
of their success.

219
00:22:52,204 --> 00:22:58,126
For some, their skin has allowed them
to become masters of disguise.

220
00:22:59,336 --> 00:23:01,630
[uplifting music continues]

221
00:23:13,725 --> 00:23:18,855
But skin can also be used
to scare off an attacker.

222
00:23:18,939 --> 00:23:20,690
[hisses]

223
00:23:23,235 --> 00:23:28,407
Even then, there are times
when more drastic measures are called for.

224
00:23:29,324 --> 00:23:30,659
[music ends]

225
00:23:35,539 --> 00:23:37,874
It may have escaped the bird,

226
00:23:38,458 --> 00:23:41,878
but lizards aren't known
for their swimming prowess.

227
00:23:46,258 --> 00:23:52,264
Yet the anole lizard of Costa Rica
has an extraordinary survival technique.

228
00:23:54,558 --> 00:24:00,605
As it exhales, it creates a bubble
that sticks to its water-repellent skin…

229
00:24:03,400 --> 00:24:06,862
forming its very own diving bell…

230
00:24:09,322 --> 00:24:12,242
and allowing it to stay hidden underwater

231
00:24:13,535 --> 00:24:16,246
for up to 15 minutes.

232
00:24:23,003 --> 00:24:27,799
Today's reptiles are such experts
at living in the margins,

233
00:24:28,592 --> 00:24:32,012
it's hard to imagine
they once dominated our planet.

234
00:24:34,598 --> 00:24:36,600
[birds tweeting]

235
00:24:36,683 --> 00:24:38,685
[tense ambient music playing]

236
00:24:41,605 --> 00:24:44,816
But there's a series of islands
in Indonesia

237
00:24:46,651 --> 00:24:50,739
that offer a glimpse
into that very distant past.

238
00:24:57,746 --> 00:25:01,500
For here, lizards still rule.

239
00:25:13,053 --> 00:25:16,973
Recently hatched and already curious…

240
00:25:23,939 --> 00:25:28,193
this youngster is starting life
in a lizard paradise.

241
00:25:34,533 --> 00:25:36,618
The only issue she has…

242
00:25:36,701 --> 00:25:38,703
[ominous music playing]

243
00:25:39,538 --> 00:25:40,872
…is her relatives.

244
00:25:46,878 --> 00:25:50,257
For this is a baby Komodo dragon…

245
00:25:53,635 --> 00:25:56,763
and Komodos are cannibals…

246
00:26:00,100 --> 00:26:04,062
smelling the air with their forked tongue
to find their prey.

247
00:26:08,900 --> 00:26:10,026
[grunts]

248
00:26:13,154 --> 00:26:15,198
For the world's largest lizards…

249
00:26:17,367 --> 00:26:21,121
baby dragons make perfect snacks.

250
00:26:31,548 --> 00:26:33,550
[grunting]

251
00:26:35,594 --> 00:26:39,389
Luckily for her,
a nest of buried Komodo eggs

252
00:26:41,141 --> 00:26:43,351
offers an easier meal.

253
00:26:58,450 --> 00:27:03,079
But it won't satisfy this monster
for long.

254
00:27:08,084 --> 00:27:10,086
[hisses]

255
00:27:19,471 --> 00:27:23,058
It'll be seven or eight years
of hiding in trees

256
00:27:24,768 --> 00:27:27,979
before she's big enough
to stand up for herself.

257
00:27:38,698 --> 00:27:40,116
Too heavy to climb,

258
00:27:40,784 --> 00:27:45,830
the adult goes in search
of something more accessible.

259
00:27:52,087 --> 00:27:53,088
[hisses]

260
00:27:53,171 --> 00:27:54,506
[fly buzzes]

261
00:27:57,425 --> 00:28:02,389
A thick layer of mud
can't disguise this animal's scent.

262
00:28:03,014 --> 00:28:05,016
[snorts, grunts]

263
00:28:07,435 --> 00:28:09,437
[hissing]

264
00:28:13,400 --> 00:28:15,568
[snorts]

265
00:28:24,619 --> 00:28:27,122
Water buffalo are ever vigilant…

266
00:28:31,334 --> 00:28:34,045
wary of their reptilian overlords.

267
00:28:40,969 --> 00:28:43,138
[bleating]

268
00:28:46,516 --> 00:28:50,603
But buffalo calves
are not as savvy as their parents.

269
00:28:50,687 --> 00:28:52,689
[suspenseful music playing]

270
00:29:01,364 --> 00:29:02,949
[hisses]

271
00:29:09,038 --> 00:29:10,749
[growling]

272
00:29:12,459 --> 00:29:13,752
[calf bleats]

273
00:29:13,835 --> 00:29:15,503
[buffalo grunting]

274
00:29:15,587 --> 00:29:18,465
[snorting, grunting]

275
00:29:20,341 --> 00:29:22,385
[dramatic music playing]

276
00:29:25,680 --> 00:29:27,474
-[snorting]
-[grunting]

277
00:29:28,767 --> 00:29:31,060
The dragon has lost its kill,

278
00:29:32,061 --> 00:29:33,938
but only temporarily.

279
00:29:36,065 --> 00:29:38,777
Venom from a gland in its jaw

280
00:29:40,361 --> 00:29:43,031
prevents the blood of its prey
from clotting,

281
00:29:44,032 --> 00:29:46,993
leading to a dangerous drop
in blood pressure.

282
00:29:47,076 --> 00:29:49,078
[somber music playing]

283
00:29:51,873 --> 00:29:53,124
The result

284
00:29:54,542 --> 00:29:55,794
is inevitable.

285
00:30:01,925 --> 00:30:05,345
This is an echo of what life was like

286
00:30:06,513 --> 00:30:08,223
back in the Triassic.

287
00:30:12,393 --> 00:30:14,938
Mammals must fight for their lives,

288
00:30:15,647 --> 00:30:19,818
while reptiles dominate
with a confident swagger.

289
00:30:23,488 --> 00:30:28,827
But perhaps the most remarkable chapter
of that early era of reptile supremacy…

290
00:30:30,995 --> 00:30:34,833
was when some of them
turned their back on the land

291
00:30:36,417 --> 00:30:38,878
and returned to the ocean.

292
00:30:38,962 --> 00:30:40,964
[music fades]

293
00:30:43,341 --> 00:30:45,343
[peaceful music playing]

294
00:30:49,514 --> 00:30:50,723
Turtles.

295
00:30:54,519 --> 00:30:56,855
Whether pushed here through competition

296
00:30:58,273 --> 00:31:00,942
or enticed by opportunity…

297
00:31:03,736 --> 00:31:07,031
turtles went back
to the seas their ancestors left,

298
00:31:07,907 --> 00:31:12,328
and today inhabit
all but the coldest oceans.

299
00:31:16,499 --> 00:31:21,838
Yet once a year, adult females
must still return to dry land

300
00:31:21,921 --> 00:31:23,715
to lay their eggs.

301
00:31:27,552 --> 00:31:30,805
Here, on the edge
of the Great Barrier Reef…

302
00:31:33,099 --> 00:31:35,643
they come together in their thousands.

303
00:31:44,694 --> 00:31:46,446
Aggregations like this

304
00:31:46,529 --> 00:31:49,949
have been one
of nature's greatest spectacles

305
00:31:50,033 --> 00:31:51,701
for millions of years.

306
00:31:51,784 --> 00:31:53,786
[music swells]

307
00:32:07,258 --> 00:32:09,928
There's a good reason for this gathering.

308
00:32:11,304 --> 00:32:12,764
Safety in numbers.

309
00:32:16,059 --> 00:32:18,061
[music fades]

310
00:32:18,144 --> 00:32:21,272
Turtles first evolved
back in the Triassic.

311
00:32:23,650 --> 00:32:30,156
But by the time they'd conquered the seas,
the ocean was home to deadly predators.

312
00:32:33,368 --> 00:32:38,581
At eight meters long,
this is a plesiosaur.

313
00:32:38,665 --> 00:32:40,667
[tense music playing]

314
00:32:49,092 --> 00:32:51,135
It, too, is a reptile,

315
00:32:52,595 --> 00:32:56,891
but one that spends
its entire life at sea.

316
00:33:10,363 --> 00:33:12,365
[tense music builds]

317
00:33:40,727 --> 00:33:42,729
[music fades]

318
00:33:43,604 --> 00:33:44,772
[crunching]

319
00:33:46,149 --> 00:33:49,944
As the plesiosaur can only eat so much,

320
00:33:50,028 --> 00:33:53,031
gathering in huge numbers like this

321
00:33:54,073 --> 00:33:56,909
allows many more turtles to survive.

322
00:34:00,413 --> 00:34:01,914
All that remains

323
00:34:03,124 --> 00:34:06,836
is to haul themselves up onto the beach
where they were born

324
00:34:08,379 --> 00:34:12,341
and find the perfect spot
to lay their eggs.

325
00:34:12,425 --> 00:34:14,427
[poignant music playing]

326
00:34:31,194 --> 00:34:36,657
Almost two months later,
and the females' efforts are rewarded.

327
00:34:39,452 --> 00:34:40,495
Hatchlings.

328
00:34:44,415 --> 00:34:48,461
But each one
now has its own gauntlet to run…

329
00:34:52,590 --> 00:34:56,010
as they instinctively head
towards the ocean.

330
00:35:08,856 --> 00:35:10,858
[ominous music playing]

331
00:35:16,906 --> 00:35:18,616
[dramatic music playing]

332
00:35:18,699 --> 00:35:20,034
Pterosaurs.

333
00:35:22,245 --> 00:35:25,081
Long before the existence of birds,

334
00:35:25,665 --> 00:35:30,545
this group of ancient reptiles
made a huge evolutionary step.

335
00:35:39,011 --> 00:35:40,596
They took to the wing…

336
00:35:46,394 --> 00:35:47,770
[squawking]

337
00:35:48,396 --> 00:35:51,649
…and became masters of the air.

338
00:36:01,159 --> 00:36:02,535
Totally defenseless…

339
00:36:05,079 --> 00:36:07,039
this hatchling's only chance…

340
00:36:09,083 --> 00:36:10,418
is to carry on…

341
00:36:14,172 --> 00:36:16,382
ignoring the near misses,

342
00:36:17,633 --> 00:36:22,638
and hoping that the pterosaurs
will be spoiled for choice.

343
00:36:24,098 --> 00:36:25,641
[squawks]

344
00:36:27,602 --> 00:36:28,936
Every lucky escape…

345
00:36:29,520 --> 00:36:30,646
[squawks]

346
00:36:31,772 --> 00:36:34,108
…brings it closer to the water's edge.

347
00:36:45,036 --> 00:36:49,290
Yet even those that reach the oceans
aren't safe.

348
00:36:57,590 --> 00:36:59,759
[squawking]

349
00:37:03,471 --> 00:37:05,598
Only by getting to deeper water

350
00:37:07,516 --> 00:37:09,769
can it avoid the pterosaurs…

351
00:37:14,190 --> 00:37:16,776
and escape into the blue.

352
00:37:27,745 --> 00:37:30,248
[stirring music playing]

353
00:37:36,128 --> 00:37:40,800
Reptiles once ruled the skies
and the waves.

354
00:37:42,468 --> 00:37:44,345
But despite their supremacy,

355
00:37:45,304 --> 00:37:51,394
Pterosaurs and plesiosaurs
would both go extinct in time.

356
00:37:51,477 --> 00:37:53,479
[stirring music continues]

357
00:38:09,578 --> 00:38:11,580
[music fades]

358
00:38:11,664 --> 00:38:17,837
Yet one of the ruling reptiles
from this era has survived.

359
00:38:23,467 --> 00:38:26,595
They're such perfect stealth hunters

360
00:38:26,679 --> 00:38:30,016
that even after 200 million years…

361
00:38:32,351 --> 00:38:34,562
little has bettered them.

362
00:38:37,773 --> 00:38:38,858
[snorts]

363
00:38:38,941 --> 00:38:40,860
Oblivious to the danger…

364
00:38:40,943 --> 00:38:42,194
[snorts]

365
00:38:42,278 --> 00:38:45,072
…wildebeest come to quench their thirst.

366
00:38:54,540 --> 00:38:56,542
[tense ambient music playing]

367
00:39:01,839 --> 00:39:03,632
[crocodile snarls]

368
00:39:04,759 --> 00:39:06,761
[buffalo bellowing]

369
00:39:30,117 --> 00:39:31,786
[snarls]

370
00:39:36,457 --> 00:39:37,750
Almost.

371
00:39:40,628 --> 00:39:41,962
But it doesn't matter.

372
00:39:44,465 --> 00:39:48,344
The Nile crocodile knows
the wildebeest will return…

373
00:39:52,223 --> 00:39:54,183
just as they always have.

374
00:39:56,185 --> 00:39:57,269
[snorts]

375
00:40:02,691 --> 00:40:07,780
To avoid detection,
the crocodile silently submerges…

376
00:40:09,907 --> 00:40:11,200
holding its breath

377
00:40:13,160 --> 00:40:14,787
for up to an hour.

378
00:40:22,169 --> 00:40:23,462
[snorts]

379
00:40:24,964 --> 00:40:29,510
Crocodiles can slow their heart rate
to just two beats a minute…

380
00:40:34,140 --> 00:40:36,725
almost completely shutting down…

381
00:40:40,312 --> 00:40:44,358
in a way the reptiles perfected
millions of years ago.

382
00:40:44,442 --> 00:40:46,444
[tense music playing]

383
00:41:02,835 --> 00:41:06,172
Yet in the moment it launches its attack…

384
00:41:11,844 --> 00:41:13,429
it goes from inertia…

385
00:41:16,974 --> 00:41:18,601
to explosive energy

386
00:41:19,560 --> 00:41:21,770
in just a fraction of a second…

387
00:41:28,068 --> 00:41:30,446
generating enough speed and power…

388
00:41:37,203 --> 00:41:39,788
to launch its five-meter-long body…

389
00:41:41,999 --> 00:41:44,460
out of the water…

390
00:41:52,051 --> 00:41:53,719
all on an empty stomach…

391
00:41:56,180 --> 00:41:57,556
and a single breath.

392
00:42:08,192 --> 00:42:12,279
It's a technique
as successful for crocodiles now

393
00:42:14,156 --> 00:42:17,368
as it was for their prehistoric ancestors.

394
00:42:26,377 --> 00:42:31,131
Today's crocodiles
dominate the waters they live in…

395
00:42:33,759 --> 00:42:37,263
but they are not
the widespread predators they once were.

396
00:42:39,640 --> 00:42:41,308
For back in the Triassic,

397
00:42:41,892 --> 00:42:44,562
the forces of nature
would send the story of life

398
00:42:45,771 --> 00:42:48,857
in a completely new direction.

399
00:42:48,941 --> 00:42:50,943
[rumbling]

400
00:42:55,823 --> 00:43:01,120
Sustained volcanic eruptions
caused another period of global warming.

401
00:43:03,289 --> 00:43:05,124
[wind whistling]

402
00:43:05,207 --> 00:43:10,504
As sea temperatures rose,
they supercharged oceanic evaporation.

403
00:43:10,588 --> 00:43:12,590
[thunder cracking]

404
00:43:14,592 --> 00:43:21,432
In northern Pangaea, moisture-laden winds
hit a 3,000-meter-high ridge…

405
00:43:26,520 --> 00:43:30,274
creating megamonsoonal weather systems.

406
00:43:41,118 --> 00:43:43,370
And it started to rain…

407
00:43:46,999 --> 00:43:48,834
on a biblical scale.

408
00:43:52,504 --> 00:43:54,506
[epic music playing]

409
00:44:06,185 --> 00:44:08,187
[thunder cracking]

410
00:44:11,440 --> 00:44:15,277
Across the planet, storms raged.

411
00:44:29,249 --> 00:44:33,754
The downpours lasted
more than a million years…

412
00:44:37,424 --> 00:44:42,846
turning the dry deserts of early Pangaea
into a distant memory.

413
00:44:52,940 --> 00:44:57,778
In the far north, torrents flowed
from high in the mountains.

414
00:45:05,869 --> 00:45:07,871
[epic music intensifies]

415
00:45:38,527 --> 00:45:40,070
[music fades]

416
00:45:40,154 --> 00:45:43,991
Surface water rewrote the landscape…

417
00:45:46,410 --> 00:45:49,705
carrying with it nutrient-rich silt.

418
00:45:53,459 --> 00:45:59,506
The waterways soon covered
more than 1.6 million square kilometers…

419
00:46:06,305 --> 00:46:09,391
an area the size of Alaska,

420
00:46:10,768 --> 00:46:14,521
creating the largest delta
in Earth's history.

421
00:46:18,901 --> 00:46:24,573
These fertile waterways
became the lifeblood of a new world…

422
00:46:27,701 --> 00:46:29,870
the fuel for evolution.

423
00:46:35,167 --> 00:46:37,503
Conifers rose to the fore.

424
00:46:42,382 --> 00:46:45,552
And for the first time
since the Permian extinction…

425
00:46:49,056 --> 00:46:54,061
our planet returned
to a forested land of giants.

426
00:46:55,562 --> 00:46:57,564
[rousing music playing]

427
00:47:15,332 --> 00:47:20,379
Many ancient reptiles
failed to adapt to this new landscape.

428
00:47:25,050 --> 00:47:29,388
But one group embraced
this change in plant life…

429
00:47:32,266 --> 00:47:35,727
and would soon rise
to take over the world.

430
00:47:35,811 --> 00:47:38,146
[tranquil music playing]

431
00:47:46,822 --> 00:47:51,285
The youngsters start life
much like other reptiles.

432
00:48:01,086 --> 00:48:02,921
They hatch from eggs…

433
00:48:09,136 --> 00:48:10,679
they have scaly skin…

434
00:48:17,519 --> 00:48:20,022
and they are left to fend for themselves…

435
00:48:20,105 --> 00:48:22,190
[mewling]

436
00:48:23,108 --> 00:48:25,360
…from the moment they enter the world.

437
00:48:27,404 --> 00:48:29,406
[intriguing music playing]

438
00:48:35,162 --> 00:48:36,914
But there are differences.

439
00:48:42,586 --> 00:48:45,797
They have a much more efficient
breathing system

440
00:48:45,881 --> 00:48:49,885
that continuously pumps blood
across their lungs…

441
00:48:54,640 --> 00:48:56,141
allowing them to run

442
00:48:56,224 --> 00:48:58,852
without having to stop
to catch their breath.

443
00:49:10,614 --> 00:49:12,991
[purrs, chirps]

444
00:49:15,994 --> 00:49:21,750
Their legs extend beneath their body
rather than to the side

445
00:49:21,833 --> 00:49:24,836
so they can walk upright.

446
00:49:43,313 --> 00:49:47,442
This allows tiny hatchlings
to grow into adults

447
00:49:47,526 --> 00:49:50,737
that are 50 times their size.

448
00:49:53,949 --> 00:49:55,200
[soft thud]

449
00:49:59,287 --> 00:50:02,499
They're part of the reptile family tree,

450
00:50:03,166 --> 00:50:06,294
but are their own unique branch.

451
00:50:07,295 --> 00:50:09,297
[majestic music playing]

452
00:50:21,476 --> 00:50:24,521
Early giants, like Plateosaurus,

453
00:50:24,604 --> 00:50:27,357
can reach the new taller food sources.

454
00:50:27,441 --> 00:50:28,608
[bellows]

455
00:50:30,110 --> 00:50:33,947
Their stomachs can digest
the tough conifer needles…

456
00:50:36,700 --> 00:50:38,243
and their sheer volume

457
00:50:38,326 --> 00:50:41,830
helps them maintain
a higher body temperature

458
00:50:41,913 --> 00:50:43,707
day and night.

459
00:50:59,514 --> 00:51:04,061
It's a winning formula
that will herald a new age.

460
00:51:04,144 --> 00:51:06,396
[music intensifies, then ends]

461
00:51:14,154 --> 00:51:15,322
The Jurassic.

462
00:51:18,867 --> 00:51:20,869
[stirring music playing]

463
00:51:33,131 --> 00:51:35,592
This new dynasty would rule

464
00:51:36,343 --> 00:51:40,180
for more than 150 million years.

465
00:51:40,806 --> 00:51:42,808
[stirring music continues]

466
00:51:49,773 --> 00:51:55,737
A reign that would see the rise
of some of the most iconic creatures

467
00:51:55,821 --> 00:51:57,781
to ever walk the Earth.

468
00:52:04,371 --> 00:52:08,792
Welcome to the age of dinosaurs.

469
00:52:08,875 --> 00:52:10,877
[bellowing]

470
00:52:16,675 --> 00:52:18,635
[epic instrumental music playing]