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00:00:16,517 --> 00:00:21,563
Surely, one of the most remarkable animals
that has ever existed,

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00:00:22,105 --> 00:00:26,318
and certainly one of the most famous,
is a dinosaur.

3
00:00:27,361 --> 00:00:29,613
Tyrannosaurus rex.

4
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An animal to spark the imagination
for all of us.

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What kind of an animal was it?

6
00:00:38,330 --> 00:00:41,542
What did it look like? How did it live?

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00:00:41,625 --> 00:00:45,587
Now, scientific research has answered
such questions.

8
00:00:45,671 --> 00:00:47,923
And not just about T. rex,

9
00:00:48,006 --> 00:00:51,343
but the other species
that lived alongside it.

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00:00:51,426 --> 00:00:58,016
And the latest imaging technology
enables us to bring them all to life.

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[grunting]

12
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[David Attenborough]
Planet Earth, 66 million years ago.

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[roars]

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[roars]

15
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The skies are filled with flying giants.

16
00:01:20,038 --> 00:01:24,084
In the seas,
monstrous reptiles patrol the depths.

17
00:01:26,128 --> 00:01:29,256
And on land, dinosaurs of every kind,

18
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all facing the struggle to survive.

19
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[leaves rustling]

20
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[groaning]

21
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We now know so much about a world
that was ruled by the dinosaurs.

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[roars]

23
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[shrieks]

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This is their story.

25
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[Attenborough]
The forests in South America

26
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contain some of the world's tallest trees.

27
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They can grow
to a height of over 300 feet.

28
00:02:33,570 --> 00:02:36,573
But there are animal giants here too.

29
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[tree trunk cracking]

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[dinosaur bellowing]

31
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Plant-eating dinosaurs.

32
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These are Austroposeidon.

33
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They're 80 feet long.

34
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And they have colossal appetites.

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Their teeth are used not to chew,

36
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but simply to cut.

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A herd like this one can consume
ten tons of vegetation every day.

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They prefer the tender, young leaves
that grow on the tips of the branches.

39
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But if they find trees
that are even taller than they are,

40
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they're not defeated.

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[bellows]

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They use their great weight
and their 8-inch-thick breastbone

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to simply push the trees over.

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Success.

45
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But life in the forest is always a battle.

46
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Especially when new space is created.

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Plants race to claim the light…

48
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and use every kind of method
to gain the upper hand.

49
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The gap in the canopy is soon closed.

50
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Over three-quarters of the world's land
is covered by plants and trees.

51
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This prehistoric planet is a green planet.

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[dinosaur growling]

53
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Many different species of dinosaur
live in forests.

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Triceratops,
one of the biggest in North America.

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They can be 26 feet long.

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The huge frills on their heads
are used for protection when they fight.

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But plants have defenses too.

58
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Poisonous toxins.

59
00:07:09,721 --> 00:07:12,724
These are particularly dangerous
for youngsters.

60
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This calf weighs only
a 50th of the weight of his mother.

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[yelps]

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And the plant's toxins
could make him very sick indeed.

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00:07:38,959 --> 00:07:43,088
But Triceratops have
a way of dealing with such poisons.

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They use an antidote.

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One source of it lies in a cave
to which they pay regular visits.

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This youngster, however,
has never been in here before.

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[huffs]

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They have to find their way
along a passage

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that, over many millennia,
has been eroded by an underground river.

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They are now beyond the reach of light.

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They can't see a thing.

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The calf must stick close to his family.

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[calf yelps]

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[calf yelps]

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But not too close.

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[calf yelps]

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[wailing]

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Now, one wrong turn could be disastrous.

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[wailing continues]

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At last, the herd reaches
the place they need to visit.

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This is the antidote: a special clay.

82
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These are known as clay licks,
and they're visited time and again.

83
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But someone is missing.

84
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Where is her calf?

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[bellows]

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[calf yelping]

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[parent bellows]

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[yelping continues]

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[calf grunts]

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[bellows]

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Luck was on the youngster's side.

92
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Once he's lined his stomach with clay,

93
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he too will be protected from the poisons
in the leaves on which he feeds.

94
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Soon they will all head back
to the forest and daylight.

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In fact, very little of the sun's light

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reaches the floor of these dense forests.

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In Patagonia,

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the thick vegetation stretches unbroken
for hundreds of miles.

99
00:13:04,701 --> 00:13:09,414
But occasionally, there are
mysterious clearings, like this one.

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[dinosaur growling]

101
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It's the work of a two-ton,
12-foot tall Carnotaurus. A male.

102
00:13:39,862 --> 00:13:43,574
Clearing this patch
has taken him a long time.

103
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And it needs constant attention
if it is to remain tidy.

104
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It's a stage
on which he can show off to females.

105
00:14:05,220 --> 00:14:08,807
All is ready, and he announces the fact.

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[guttural calling]

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His calls are low-pitched

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and travel much farther
through the dense vegetation

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than higher-pitched ones would do.

110
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[calling continues]

111
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At last, a female arrives.

112
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She's bigger than the male
and more powerful.

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Now, somehow, he must impress her.

114
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And he may only get this one chance.

115
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She watches him carefully.

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If he is going to impress her,

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he must do so
in the most extraordinary way.

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He doesn't have huge antlers,
nor a spectacular tail.

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But he does have a pair of tiny,
apparently useless arms.

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And each has a ball and socket joint
at its base

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that enables him
to move them independently.

122
00:16:51,595 --> 00:16:52,721
Not today.

123
00:17:00,020 --> 00:17:03,398
How could he have done better? Who knows?

124
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For now, it's back to litter picking.

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This is East Asia.

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00:17:27,422 --> 00:17:31,677
In these mountain forests,
autumn arrives early.

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This is when many trees
produce their fruit.

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And amongst the most highly prized
are the nuts of the Ginkgo tree.

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A bonanza
for dinosaurs called Corythoraptors.

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Although they have feathers,
they're flightless.

131
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These have found
a particularly abundant fall of fruit.

132
00:18:18,974 --> 00:18:22,978
But such gatherings can attract
unwelcome attention.

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Qianzhousaurus,
the top predator in these Asiatic forests.

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00:18:40,829 --> 00:18:43,832
This is a female, over 30 feet long.

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00:18:48,587 --> 00:18:53,091
If she is to catch a Corythoraptor,
she'll have to get close.

136
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There's not much cover here.

137
00:19:08,232 --> 00:19:12,361
But her prey have still not noticed her.

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[squawking]

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00:19:55,404 --> 00:19:56,738
[roars]

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She has failed.

141
00:20:04,121 --> 00:20:05,873
But then, most hunts,

142
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throughout the history of life,
fail most of the time.

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[thunder rumbling]

144
00:20:18,343 --> 00:20:20,596
As the seasonal winds strengthen,

145
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many of the trees in these temperate
forests start to lose their leaves.

146
00:20:29,688 --> 00:20:32,274
Winter will be a time of hardship.

147
00:20:38,155 --> 00:20:43,160
Nevertheless, a storm does create
a brief opportunity for hunters.

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00:20:45,746 --> 00:20:47,247
She's trying again.

149
00:20:51,710 --> 00:20:57,341
She's less conspicuous in the gloom,
and the gusting wind is distracting.

150
00:21:17,861 --> 00:21:19,863
[leaves rustling]

151
00:21:32,084 --> 00:21:33,293
[grunts]

152
00:21:48,642 --> 00:21:50,811
An 80-pound prize.

153
00:21:53,981 --> 00:21:57,985
All the more valuable,
since winter is now closing in.

154
00:22:06,618 --> 00:22:08,662
In the forests of North America,

155
00:22:09,246 --> 00:22:14,626
there is an additional annual hazard
for forest dwellers.

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00:22:14,710 --> 00:22:16,712
[fire crackling]

157
00:22:24,928 --> 00:22:28,974
Fire, started by a strike of lightning.

158
00:22:38,150 --> 00:22:43,363
As it spreads, temperatures rise
to over 2,000 degrees Fahrenheit.

159
00:22:57,628 --> 00:23:01,048
The flames rise
several hundred feet into the air.

160
00:23:10,432 --> 00:23:13,435
[dinosaur bellowing]

161
00:23:16,146 --> 00:23:17,814
Most animals flee.

162
00:23:19,942 --> 00:23:24,154
But this Edmontosaurus
has a family to care for.

163
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[bellowing continues]

164
00:23:26,573 --> 00:23:28,242
She doesn't abandon them.

165
00:23:30,327 --> 00:23:35,791
Now they must keep one step ahead
of the blaze until it burns out.

166
00:23:47,302 --> 00:23:50,264
This may look catastrophic.

167
00:23:57,312 --> 00:24:01,316
But remarkably, some plants must be burnt

168
00:24:01,400 --> 00:24:04,027
if they are to complete their life cycle.

169
00:24:08,240 --> 00:24:12,911
The intense heat is needed
to open the cones of the pine trees…

170
00:24:15,372 --> 00:24:17,249
and release their seeds.

171
00:24:28,260 --> 00:24:31,597
And only a few hours
after the fire has passed,

172
00:24:33,348 --> 00:24:36,101
animals begin to return.

173
00:24:39,980 --> 00:24:42,316
Beetles are among the first.

174
00:24:45,736 --> 00:24:47,696
They start to lay their eggs.

175
00:24:49,156 --> 00:24:52,618
When they hatch,
the larvae will be the first to feast

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00:24:52,701 --> 00:24:56,121
on the near-limitless supply of dead wood.

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00:25:06,757 --> 00:25:10,260
This Atrociraptor is an opportunist.

178
00:25:18,227 --> 00:25:21,939
Quick to return
when there's food on offer.

179
00:25:27,152 --> 00:25:29,530
And there's something else
to be gained here.

180
00:25:40,332 --> 00:25:42,960
Smoke is an insecticide…

181
00:25:47,214 --> 00:25:51,218
and it can help an animal
to get rid of its parasites.

182
00:25:57,224 --> 00:25:59,351
But you do have to be careful.

183
00:26:01,186 --> 00:26:04,815
[growling]

184
00:26:15,450 --> 00:26:18,537
A two-ton ankylosaur.

185
00:26:23,083 --> 00:26:26,920
It also finds something worth eating
after a fire.

186
00:26:36,096 --> 00:26:37,181
Charcoal.

187
00:26:39,766 --> 00:26:45,230
It will bind with many of the plant toxins
in its stomach and neutralize them.

188
00:26:48,734 --> 00:26:51,153
[bellows]

189
00:26:57,242 --> 00:27:01,246
The female Edmontosaurus
is leaving the forest.

190
00:27:03,957 --> 00:27:05,876
[bellows]

191
00:27:08,337 --> 00:27:12,716
Against the odds,
she's led both her babies to safety.

192
00:27:21,433 --> 00:27:23,519
[bellows]

193
00:27:27,189 --> 00:27:32,486
They will have to find new pastures
until the forest plants recover.

194
00:27:42,329 --> 00:27:46,750
Even where fires are rare,
trees do not live forever.

195
00:27:47,292 --> 00:27:52,422
And after they die, they become food
for a very different kind of organism.

196
00:27:52,965 --> 00:27:54,967
[insects chirping]

197
00:27:57,636 --> 00:28:02,057
At night,
some of them become eerily conspicuous.

198
00:28:05,936 --> 00:28:08,313
Down on the forest floor…

199
00:28:11,525 --> 00:28:13,527
fungi appear…

200
00:28:15,487 --> 00:28:17,739
and start to glow.

201
00:28:25,831 --> 00:28:30,919
They produce their light by chemical
reactions deep within their tissues.

202
00:28:35,048 --> 00:28:37,968
But why they do so is a mystery.

203
00:28:41,597 --> 00:28:44,266
It may be
because the light attracts insects,

204
00:28:44,349 --> 00:28:47,728
which then help
to spread the spores of the fungus.

205
00:28:56,236 --> 00:28:58,322
Here, in central Asia,

206
00:28:58,405 --> 00:29:03,076
the nighttime forest
is filled with strange sounds.

207
00:29:03,952 --> 00:29:05,746
[snoring]

208
00:29:09,791 --> 00:29:12,753
Giant sauropods are asleep.

209
00:29:19,259 --> 00:29:22,054
There are air sacs in their head and neck,

210
00:29:22,137 --> 00:29:26,350
which reduce their weight
but also amplify their snores.

211
00:29:30,979 --> 00:29:33,398
But not everyone is asleep.

212
00:29:37,569 --> 00:29:42,783
For smaller creatures, it's safer to be
out in the darkness than during the day.

213
00:29:45,661 --> 00:29:50,791
These Therizinosaurus
hatched just six months ago.

214
00:29:55,879 --> 00:30:00,634
Barely three feet long,
they are only a tenth of their adult size.

215
00:30:03,387 --> 00:30:08,892
Their claws may look like daggers,
but they're used more like salad servers…

216
00:30:12,521 --> 00:30:15,315
because these are plant eaters.

217
00:30:18,151 --> 00:30:23,907
This forest, however, has all kinds
of food if you know where to look.

218
00:30:26,076 --> 00:30:27,077
Honey.

219
00:30:29,371 --> 00:30:33,125
It's dripping from a bees' nest
up in the branches.

220
00:30:36,837 --> 00:30:41,091
Bees usually build their nests
beyond the reach of ground dwellers.

221
00:30:41,175 --> 00:30:42,718
[bees buzzing]

222
00:30:42,801 --> 00:30:45,262
But this one is lower than most.

223
00:30:47,764 --> 00:30:49,766
And it's too good to miss.

224
00:30:50,726 --> 00:30:53,270
[grunting]

225
00:30:55,480 --> 00:30:57,482
[bees buzzing]

226
00:31:04,615 --> 00:31:05,616
[grunts]

227
00:31:08,410 --> 00:31:13,790
Unlike most dinosaurs,
young Therizinosaurus can climb.

228
00:31:19,004 --> 00:31:21,798
Although they're not exactly experts.

229
00:31:25,844 --> 00:31:27,971
[grunting]

230
00:31:48,534 --> 00:31:50,536
[bees buzzing]

231
00:31:55,791 --> 00:32:01,839
Angry bees produce a Mexican wave
to warn intruders to keep away…

232
00:32:08,387 --> 00:32:10,222
or suffer the consequences.

233
00:32:14,643 --> 00:32:17,646
[squawking]

234
00:32:32,703 --> 00:32:33,954
[squawks]

235
00:32:39,543 --> 00:32:42,254
An adult Therizinosaurus.

236
00:32:47,634 --> 00:32:53,098
It's huge, nearly 30 feet tall
and weighing five tons.

237
00:32:56,268 --> 00:32:58,061
[bees buzzing]

238
00:33:13,118 --> 00:33:16,496
Nothing the bees can do deters this one.

239
00:33:35,015 --> 00:33:37,476
At last, a little treat.

240
00:33:39,478 --> 00:33:42,564
And a few more stings.

241
00:33:56,203 --> 00:33:57,788
[dinosaur bellowing]

242
00:33:57,871 --> 00:34:03,126
Even by day, it's still dark
in the understory of the dense forests,

243
00:34:03,210 --> 00:34:05,546
such as this one in Europe.

244
00:34:09,174 --> 00:34:12,844
Animals of any kind
are difficult to distinguish.

245
00:34:18,934 --> 00:34:20,811
Yet, they're everywhere.

246
00:34:26,233 --> 00:34:29,485
Telmatosaurus seldom breaks cover.

247
00:34:39,413 --> 00:34:42,123
And equally inconspicuous…

248
00:34:46,043 --> 00:34:47,420
Zalmoxes.

249
00:34:49,965 --> 00:34:53,302
The last
of a very ancient dinosaur lineage.

250
00:34:56,929 --> 00:35:00,809
This forest
is one of their few remaining strongholds.

251
00:35:04,771 --> 00:35:10,777
Seven inches tall, baby Zalmoxes are
no more than snacks for many predators.

252
00:35:11,695 --> 00:35:14,740
But snacks are nonetheless worth eating…

253
00:35:16,533 --> 00:35:18,327
so they have to be cautious.

254
00:35:35,928 --> 00:35:37,346
[Zalmoxes yelps]

255
00:35:48,524 --> 00:35:52,694
Hatzegopteryx stands 15 feet tall.

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It is, in fact, a pterosaur,
a reptile with wings,

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that here, as it stalks through the trees,
it has to keep tightly folded.

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This forest, so rich in small creatures,
is one of its regular hunting grounds.

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It stands
on the southernmost edge of Europe.

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This is the heaviest animal ever to fly,

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and there is nowhere else here
where it can open its gigantic wings,

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which are over 30 feet across.

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Many of the forest's permanent residents
regularly come down here…

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because the plants are coated
with sea spray

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and are a welcome source of salt.

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Here, sauropods can meet one another,
renewing family bonds…

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and creating new ones.

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But for Hatzegopteryx,
the beach is a launching pad.

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[squawking]

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Now his wings will carry him
to yet another forest,

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where life proliferates
more variously and more abundantly

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than anywhere else
on our prehistoric planet.

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To discover the science
behind the stories,

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go now
to the Prehistoric Planet show page.