1
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[mysterious music playing]

2
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[Rebel Wilson]
For a quirky mix of creatures…

3
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look no further…

4
00:00:30,697 --> 00:00:32,073
[bellows]

5
00:00:32,157 --> 00:00:33,867
…than the marsupials.

6
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Those mammalian misfits

7
00:00:39,080 --> 00:00:40,206
with the pouch.

8
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They might seem a bit bizarre…

9
00:00:45,795 --> 00:00:48,048
but don't underestimate them.

10
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[shrieking]

11
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With unexpected superpowers

12
00:00:56,765 --> 00:00:58,641
and amazing adaptability…

13
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they have conquered a continent.

14
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[grunts]

15
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These high-altitude valleys

16
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are home to an iconic marsupial.

17
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The eastern grey kangaroo.

18
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[didgeridoo music playing]

19
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Today, a new roo
is being welcomed into the world.

20
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All kangaroo babies
start out the same way.

21
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Little more than an embryo.

22
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Blind, with hind limbs barely grown,

23
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he must scale a wall of fur
six times his height.

24
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His goal?

25
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Mum's pouch.

26
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The pouch keeps the young joey warm,

27
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fed,

28
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and safe…

29
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[upbeat music plays]

30
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…until he's ready to emerge.

31
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Fast forward six months.

32
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The eastern grey joey
takes his first look at the world.

33
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[grunting]

34
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To learn he's part of a group,

35
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known as a mob.

36
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Mum and a handful of females,

37
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jealously guarded by the boss.

38
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That's his dad.

39
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Joey is about to discover
the secret to his father's success.

40
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[growling]

41
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A lot of muscle,

42
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a lot of flexing.

43
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[growling]

44
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A challenger has arrived

45
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to contest Dad's mating rights.

46
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It's an exhibition of power…

47
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[growling]

48
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…urine…

49
00:04:05,245 --> 00:04:08,665
and there's a bit of scratching as well.

50
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Body language says, "I could fight you."

51
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"But you don't want to go there."

52
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"No, no, no."

53
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[growls]

54
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It seems to do the job.

55
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Until next time.

56
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One day, the joey will make his bid

57
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to be a kangaroo king.

58
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If he makes it that far.

59
00:05:03,761 --> 00:05:07,598
This valley is also home
to a pack of dingoes.

60
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[sinister music plays]

61
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And catching kangaroos is their specialty.

62
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[growls]

63
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At 25 miles an hour,
dingoes are pretty quick.

64
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But roos can go 40!

65
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[intense music plays]

66
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The pack looks for stragglers.

67
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[intense music continues]

68
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But no luck this time.

69
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For now, joey can relax
in the safety of Mum's pouch.

70
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It's just a simple fold of skin,

71
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but it's given marsupials a head start

72
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for millions of years.

73
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The marsupials first arose
alongside the dinosaurs

74
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on an ancient supercontinent.

75
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Today, in most places,

76
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they're being outcompeted
by placental mammals.

77
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But a number of opossums
still survive in the Americas.

78
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Including the monito del monte,

79
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the last remaining member of a family

80
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that gave rise to three-quarters
of marsupials alive today.

81
00:07:26,696 --> 00:07:29,407
It's thought that
as the supercontinent fragmented,

82
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a close relative
of this living fossil was cast away.

83
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Isolated in what is now Australia,

84
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with little competition
from other mammals,

85
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this pioneering possum's descendants
branched out across a land of opportunity.

86
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Over time, 200 different species evolved.

87
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Each with a fantastical name.

88
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Each with a unique way of life.

89
00:08:19,916 --> 00:08:21,501
Most are nocturnal…

90
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insectivores,

91
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or vegetarians.

92
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But some grew larger,

93
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fiercer,

94
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and developed a taste for meat.

95
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Filmed in 1936,

96
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the thylacine,
also know as the Tasmanian tiger,

97
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was once Australia's apex predator.

98
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This is the last time it was documented

99
00:09:00,331 --> 00:09:04,168
before human settlement
and bounty hunters wiped it out.

100
00:09:10,591 --> 00:09:14,428
Today, only a few
marsupial carnivores survive.

101
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The largest lurks in one
of the wildest corners of the continent.

102
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[sinister music plays]

103
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[squawking]

104
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[caws]

105
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A legendary beast…

106
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[caws]

107
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…with a fearsome reputation.

108
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The Tasmanian devil.

109
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[growls]

110
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A young imp might act tough…

111
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[growling]

112
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[growl echoes]

113
00:10:11,235 --> 00:10:14,363
…but he's probably
more anxious than aggressive.

114
00:10:18,159 --> 00:10:21,787
Like all devils, he prefers the dark.

115
00:10:36,469 --> 00:10:40,389
He's just eight months old,
only recently left Mum,

116
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and not had much to eat since.

117
00:10:44,518 --> 00:10:49,690
If that doesn't change soon, chances
of making it to adulthood are slim.

118
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[animal shrieking]

119
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[suspenseful music plays]

120
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His biggest problem?

121
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Other devils.

122
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[shrieking]

123
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The imp can't compete with the big boys.

124
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Two full-grown adults
scrapping over a carcass.

125
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[shrieking]

126
00:11:35,486 --> 00:11:36,362
[growling]

127
00:11:38,155 --> 00:11:40,950
But he could steal a quick snack…

128
00:11:43,577 --> 00:11:45,246
while they fight it out.

129
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[suspenseful music plays]

130
00:11:56,006 --> 00:11:58,008
[growling]

131
00:12:03,723 --> 00:12:07,977
[growling and shrieking]

132
00:12:13,649 --> 00:12:15,192
He'd better eat fast…

133
00:12:17,027 --> 00:12:19,405
[shrieking]

134
00:12:20,364 --> 00:12:22,116
…before trouble returns.

135
00:12:33,627 --> 00:12:35,379
[growling]

136
00:12:41,135 --> 00:12:44,597
All he can do is hope for some leftovers.

137
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[growling]

138
00:12:51,854 --> 00:12:56,776
But considering a devil can devour
almost half its body weight in a sitting,

139
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it could be a long wait.

140
00:13:01,113 --> 00:13:01,947
[Rebel sighs]

141
00:13:08,204 --> 00:13:11,123
[dramatic music plays]

142
00:13:12,958 --> 00:13:15,628
Come dawn, his patience has paid off.

143
00:13:17,797 --> 00:13:20,216
Well… kind of.

144
00:13:24,428 --> 00:13:29,850
Only skin and bone left,
but an imp can't afford to be picky.

145
00:13:34,772 --> 00:13:37,566
Devils do hunt sometimes,

146
00:13:37,650 --> 00:13:40,069
but they're just as happy to scavenge.

147
00:13:43,155 --> 00:13:46,200
This ability to eat the uneatable

148
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helped marsupials claim a continent.

149
00:13:54,208 --> 00:13:56,210
[waves crashing]

150
00:13:59,547 --> 00:14:04,468
Eucalyptus trees make up three-quarters
of Australia's native forest.

151
00:14:06,637 --> 00:14:09,014
Their leaves are so toxic,

152
00:14:09,098 --> 00:14:12,268
they're inedible
to almost every living thing.

153
00:14:17,481 --> 00:14:19,942
But one famous marsupial

154
00:14:20,025 --> 00:14:24,697
has found a way
to exploit this bountiful resource.

155
00:14:25,823 --> 00:14:27,533
[mellow music plays]

156
00:14:31,370 --> 00:14:34,707
This koala mum may look a little dozy,

157
00:14:35,332 --> 00:14:37,459
but she's feeding for two.

158
00:14:45,175 --> 00:14:47,219
And her body's working overtime.

159
00:14:49,638 --> 00:14:53,934
Her gut contains
a unique cocktail of microbes

160
00:14:54,018 --> 00:14:57,980
which neutralize the poisons
that would put us into a coma.

161
00:14:58,606 --> 00:15:00,608
[mellow music continues]

162
00:15:07,656 --> 00:15:11,035
But koalas aren't born
with such strong digestion.

163
00:15:12,536 --> 00:15:13,913
It has to be acquired.

164
00:15:18,375 --> 00:15:21,837
So baby is on a mix of milk and pap.

165
00:15:25,507 --> 00:15:29,553
Slushy droppings
that pass on the bacteria he'll need.

166
00:15:38,395 --> 00:15:44,234
Even with the toxins taken care of,
it takes almost all of the koala's energy

167
00:15:44,318 --> 00:15:46,987
to break down these low-nutrient leaves.

168
00:15:50,324 --> 00:15:55,371
It's no wonder
they spend 90% of their lives asleep.

169
00:15:56,538 --> 00:15:58,415
[mellow music continues]

170
00:16:11,178 --> 00:16:15,015
But not all marsupials
lead such laid-back lives.

171
00:16:26,694 --> 00:16:28,737
Meet nature's BASE jumper.

172
00:16:32,032 --> 00:16:33,492
The sugar glider.

173
00:16:41,166 --> 00:16:43,627
This palm-sized possum

174
00:16:43,711 --> 00:16:48,298
can glide half the length
of a soccer field in a single leap.

175
00:16:52,886 --> 00:16:56,890
[dramatic music playing]

176
00:17:01,478 --> 00:17:02,354
[squeaking]

177
00:17:03,647 --> 00:17:08,193
His fast-paced lifestyle
is fueled by sugary sap.

178
00:17:14,324 --> 00:17:17,870
But his teeth are too small
to cut through thick bark.

179
00:17:30,090 --> 00:17:33,677
Time to drop in
on his heavyweight cousins.

180
00:17:36,138 --> 00:17:38,849
The yellow-bellied gliders.

181
00:17:42,394 --> 00:17:47,316
Their stronger jaws are quick
to slice through the toughest trees.

182
00:17:51,820 --> 00:17:54,281
And when the yellow-bellies move on,

183
00:17:55,115 --> 00:17:57,618
the little fella takes his chance.

184
00:18:01,330 --> 00:18:02,748
[squeaking in distance]

185
00:18:02,831 --> 00:18:05,542
But gliders are social animals.

186
00:18:05,626 --> 00:18:08,420
[squeaking]

187
00:18:12,508 --> 00:18:14,676
More and more join the party.

188
00:18:15,594 --> 00:18:17,888
[squeaking]

189
00:18:21,642 --> 00:18:23,560
[high-energy music plays]

190
00:18:27,731 --> 00:18:30,651
This many uninvited guests
are hard to ignore.

191
00:18:35,489 --> 00:18:37,241
The yellow-belly's had enough.

192
00:18:37,324 --> 00:18:38,909
[dramatic music plays]

193
00:18:40,160 --> 00:18:42,204
[squeaking]

194
00:18:45,707 --> 00:18:46,875
It's fight

195
00:18:47,793 --> 00:18:48,919
or flight.

196
00:18:52,339 --> 00:18:54,383
An easy choice for a sugar glider.

197
00:19:00,514 --> 00:19:02,516
[birds chirping]

198
00:19:04,351 --> 00:19:06,353
[Australian instrumental music]

199
00:19:09,148 --> 00:19:14,111
Back in the Australian Alps,
the joey is now one big baby.

200
00:19:14,194 --> 00:19:15,612
[drums play]

201
00:19:15,696 --> 00:19:16,738
[cymbal crashes]

202
00:19:21,660 --> 00:19:25,122
Nine months old
and well on course to adulthood.

203
00:19:30,752 --> 00:19:33,172
Well, almost.

204
00:19:34,590 --> 00:19:36,592
[bouncy music plays]

205
00:19:38,844 --> 00:19:42,931
He'll continue to hop in and out
of the pouch for the next few months.

206
00:19:49,021 --> 00:19:51,315
Following in his father's footsteps,

207
00:19:51,398 --> 00:19:54,276
he's working on his tough guy image.

208
00:20:01,825 --> 00:20:03,660
And sparring with Mum.

209
00:20:09,041 --> 00:20:10,792
Lucky she's long-suffering.

210
00:20:11,335 --> 00:20:12,169
[growls softly]

211
00:20:13,754 --> 00:20:16,882
She'll put up with this
until he's a year and a half.

212
00:20:18,008 --> 00:20:19,509
Then he'll be on his own,

213
00:20:21,303 --> 00:20:22,971
fighting his way to the top.

214
00:20:28,810 --> 00:20:32,105
Because only the mob boss
is allowed to mate…

215
00:20:34,191 --> 00:20:35,984
and right now, that's Dad.

216
00:20:46,328 --> 00:20:48,080
The rival male is back.

217
00:20:48,163 --> 00:20:49,498
[growling]

218
00:20:49,581 --> 00:20:53,418
And now it's time. Time for a showdown.

219
00:20:53,919 --> 00:20:55,921
[dramatic music plays]

220
00:21:01,468 --> 00:21:02,302
[grunting]

221
00:21:08,809 --> 00:21:10,102
[growling]

222
00:21:11,186 --> 00:21:12,562
Fights are brutal.

223
00:21:14,106 --> 00:21:15,732
Sometimes fatal.

224
00:21:18,360 --> 00:21:19,903
[growling]

225
00:21:25,784 --> 00:21:27,786
[dramatic music continues]

226
00:21:36,753 --> 00:21:38,005
Rival defeated,

227
00:21:39,464 --> 00:21:41,091
Dad claims his reward.

228
00:21:45,387 --> 00:21:47,389
A little kangaroo courtship.

229
00:21:50,600 --> 00:21:51,852
His caresses…

230
00:21:54,563 --> 00:21:55,856
and sniffs

231
00:21:57,441 --> 00:21:59,026
are well-received.

232
00:22:00,902 --> 00:22:03,322
Seems joey will soon have a sibling.

233
00:22:05,282 --> 00:22:06,491
But when it arrives,

234
00:22:06,575 --> 00:22:09,536
he'll lose the security of Mum's pouch.

235
00:22:16,293 --> 00:22:18,795
[ominous music plays]

236
00:22:18,879 --> 00:22:22,883
From then on, he'll have to count
on his own turn of speed.

237
00:22:31,892 --> 00:22:35,520
The challenge of surviving
Australia's vast desert interior

238
00:22:36,271 --> 00:22:38,899
has shaped the fastest marsupial of all.

239
00:22:40,984 --> 00:22:42,361
The red kangaroo.

240
00:22:54,039 --> 00:22:56,583
Named for the males' distinctive coat,

241
00:22:58,543 --> 00:23:02,923
the red kangaroo is also
the largest marsupial in the world.

242
00:23:07,427 --> 00:23:11,181
Food sources here are few and far between,

243
00:23:12,099 --> 00:23:14,059
and water is even scarcer,

244
00:23:15,811 --> 00:23:19,731
so red kangaroos
need to keep moving to stay alive.

245
00:23:26,154 --> 00:23:29,116
They spend their lives chasing the rains.

246
00:23:36,915 --> 00:23:38,917
[dramatic music plays]

247
00:23:45,257 --> 00:23:48,468
They can cover eight meters
in a single leap.

248
00:23:50,846 --> 00:23:53,723
[uplifting music plays]

249
00:23:56,351 --> 00:24:00,856
Tendons in their hind legs
work like giant springs,

250
00:24:02,190 --> 00:24:05,735
recycling up to 70%
of the energy in every hop.

251
00:24:11,366 --> 00:24:16,163
And this rhythmic bounce also pumps
more oxygen through their lungs…

252
00:24:20,041 --> 00:24:23,295
allowing them to cruise
at 30 miles an hour.

253
00:24:24,087 --> 00:24:26,089
[uplifting music continues]

254
00:24:46,401 --> 00:24:48,695
Fast and efficient,

255
00:24:48,778 --> 00:24:52,365
red kangaroos migrate vast distances.

256
00:24:56,161 --> 00:24:58,497
When they finally reach greener pastures…

257
00:25:01,124 --> 00:25:05,754
they extract almost all the water
they need from the plants they eat…

258
00:25:10,467 --> 00:25:13,261
and can go for weeks
without drinking at all.

259
00:25:16,389 --> 00:25:18,767
With incredible specialization,

260
00:25:18,850 --> 00:25:22,479
red roos can thrive
in Australia's arid regions.

261
00:25:24,022 --> 00:25:27,526
But most marsupials
are tied to permanent water.

262
00:25:37,744 --> 00:25:41,248
Agile wallabies
are smaller cousins of red kangaroos.

263
00:25:46,127 --> 00:25:50,048
They graze around the billabongs
and creeks of Northern Australia…

264
00:25:52,884 --> 00:25:56,179
and have to regularly
come down to the water to drink.

265
00:26:07,440 --> 00:26:12,362
Saltwater crocodiles prey on the thirsty.

266
00:26:15,031 --> 00:26:17,367
[sinister drum beats]

267
00:26:25,625 --> 00:26:30,880
An ancient foe that's haunted these waters
since the time of the dinosaurs.

268
00:26:30,964 --> 00:26:32,757
[sinister music continues]

269
00:26:46,688 --> 00:26:48,690
[sinister music ends]

270
00:26:52,235 --> 00:26:54,237
[sinister music resumes]

271
00:27:09,377 --> 00:27:12,672
Collective vigilance and fast reactions

272
00:27:14,341 --> 00:27:18,720
mean, more often than not,
the wallabies get away.

273
00:27:25,518 --> 00:27:29,105
They've had millions of years
to adapt to this danger.

274
00:27:30,357 --> 00:27:33,777
But now, marsupials face new threats,

275
00:27:34,319 --> 00:27:36,237
and they're struggling to cope.

276
00:27:43,119 --> 00:27:48,667
Two hundred years ago, humans introduced
new predators to Australia.

277
00:27:51,461 --> 00:27:56,132
Feral cats kill
nearly 1.5 billion native animals a year.

278
00:28:00,428 --> 00:28:06,351
And they've played a major part
in the extinction of 22 marsupial species.

279
00:28:17,028 --> 00:28:20,907
The greater bilby
is in danger of going the same way.

280
00:28:21,950 --> 00:28:23,952
[suspenseful music plays]

281
00:28:26,121 --> 00:28:30,500
These timid creatures rely on acute senses
to navigate the night.

282
00:28:32,585 --> 00:28:38,174
Their elongated noses allow them
to sniff out seeds and fruit in the dark.

283
00:28:43,388 --> 00:28:46,141
And oversized ears help detect danger.

284
00:28:53,565 --> 00:28:56,818
But they don't have
the agility to outrun a cat.

285
00:29:01,990 --> 00:29:05,827
Greater bilbies have disappeared
from 80% of their range.

286
00:29:07,495 --> 00:29:11,708
Some wilderness areas
are now protected by cat-proof fences.

287
00:29:16,421 --> 00:29:17,630
And here,

288
00:29:17,714 --> 00:29:19,758
bilby numbers are on the rise.

289
00:29:25,513 --> 00:29:30,643
But the greatest threat facing marsupials
is even harder to control.

290
00:29:32,896 --> 00:29:34,147
In recent years,

291
00:29:34,230 --> 00:29:39,694
Australia's natural bushfires have become
more destructive than ever before.

292
00:29:48,286 --> 00:29:53,249
Climate change means occasional burns
have become regular firestorms.

293
00:30:05,178 --> 00:30:07,180
[birds squawking]

294
00:30:11,643 --> 00:30:16,773
Almost every year, thousands
of koalas and other marsupials die.

295
00:30:18,233 --> 00:30:20,235
[somber music plays]

296
00:30:28,493 --> 00:30:29,702
In the aftermath,

297
00:30:31,204 --> 00:30:33,873
it seems nothing could survive.

298
00:30:46,678 --> 00:30:50,056
But eucalyptus trees
are protected by thick bark.

299
00:30:51,683 --> 00:30:55,353
Within weeks of a burn,
they spring back to life.

300
00:30:59,065 --> 00:31:01,150
[waves crashing]

301
00:31:01,234 --> 00:31:04,404
And soon, all across Australia,

302
00:31:05,405 --> 00:31:07,615
the survivors are fighting back.

303
00:31:20,670 --> 00:31:23,089
Come the koala breeding season,

304
00:31:23,172 --> 00:31:26,384
the usually sleepy animals
are raring to go.

305
00:31:26,467 --> 00:31:29,804
[koala bellowing]

306
00:31:34,058 --> 00:31:36,728
A male's bellow carries for miles…

307
00:31:37,562 --> 00:31:39,814
[bellowing continues]

308
00:31:40,899 --> 00:31:43,401
[bellowing echoes]

309
00:31:50,366 --> 00:31:52,285
…broadcasting his location…

310
00:31:54,662 --> 00:31:56,414
showing off his size.

311
00:31:56,497 --> 00:31:59,626
[bellowing continues]

312
00:32:00,209 --> 00:32:02,211
It's an invitation to females.

313
00:32:02,295 --> 00:32:05,798
[bellowing continues]

314
00:32:05,882 --> 00:32:06,716
[grunting]

315
00:32:08,092 --> 00:32:09,469
A response.

316
00:32:09,552 --> 00:32:11,679
[grunting continues]

317
00:32:11,763 --> 00:32:13,681
But not the one he wanted.

318
00:32:19,187 --> 00:32:21,356
Disputes between males are rare…

319
00:32:26,486 --> 00:32:29,072
and pretty quickly, they turn ugly.

320
00:32:31,991 --> 00:32:33,743
[intense music plays]

321
00:32:33,826 --> 00:32:40,166
[koalas squealing]

322
00:32:43,544 --> 00:32:45,797
[squealing continues]

323
00:32:48,424 --> 00:32:53,179
[squealing continues]

324
00:32:54,764 --> 00:32:56,307
Rival dispatched.

325
00:32:58,393 --> 00:32:59,477
[koala grunts]

326
00:33:00,103 --> 00:33:02,397
Time to get back to finding a female.

327
00:33:03,106 --> 00:33:06,275
[koala bellows]

328
00:33:09,946 --> 00:33:12,740
[bellowing continues]

329
00:33:12,824 --> 00:33:16,911
At long last, his love song is heard.

330
00:33:24,794 --> 00:33:25,920
[koala squeals]

331
00:33:27,630 --> 00:33:29,048
[koala squeals]

332
00:33:29,924 --> 00:33:32,427
Well, she's in no rush to commit.

333
00:33:33,261 --> 00:33:34,721
Mm-mm-mm.

334
00:33:35,888 --> 00:33:36,723
[koala squeaks]

335
00:33:37,473 --> 00:33:40,727
But when it comes
to actually making babies,

336
00:33:41,310 --> 00:33:42,895
koalas don't hang around.

337
00:33:43,730 --> 00:33:46,566
In just 35 days, she'll give birth.

338
00:33:48,860 --> 00:33:50,278
So long as he gets his way.

339
00:33:58,703 --> 00:34:01,831
Such rapid reproduction
has helped marsupials

340
00:34:01,914 --> 00:34:06,377
to exploit every corner of the continent,
no matter how extreme.

341
00:34:08,671 --> 00:34:11,632
[majestic music playing]

342
00:34:14,302 --> 00:34:17,889
These are some of Australia's
tallest trees.

343
00:34:19,390 --> 00:34:24,020
Now, you might wonder
what a kangaroo joey is doing up here.

344
00:34:30,485 --> 00:34:32,987
But he's a tree kangaroo.

345
00:34:35,615 --> 00:34:39,118
His ancestors evolved out on the plains,

346
00:34:40,787 --> 00:34:42,371
but six million years ago,

347
00:34:43,039 --> 00:34:46,000
one daring roo took to the trees.

348
00:34:47,043 --> 00:34:50,880
Slowly but not so surely,

349
00:34:50,963 --> 00:34:54,008
its descendants
are making the canopy their home.

350
00:35:01,849 --> 00:35:04,185
They've developed stronger front limbs,

351
00:35:04,894 --> 00:35:06,437
curvier claws

352
00:35:07,063 --> 00:35:09,941
and shorter hind feet than a regular roo.

353
00:35:17,156 --> 00:35:20,076
But evolution is a slow process.

354
00:35:21,035 --> 00:35:25,873
Compared to other tree dwellers,
they're not the most graceful.

355
00:35:29,877 --> 00:35:31,462
And that's just the adults.

356
00:35:31,546 --> 00:35:32,672
[rustling]

357
00:35:37,009 --> 00:35:39,137
After seven months in the pouch,

358
00:35:39,220 --> 00:35:41,889
it's time for the joey to go it alone.

359
00:35:44,725 --> 00:35:46,727
[suspenseful music plays]

360
00:35:50,273 --> 00:35:51,566
No experience,

361
00:35:52,567 --> 00:35:53,568
under-equipped,

362
00:35:54,318 --> 00:35:55,736
and seven floors up.

363
00:36:12,044 --> 00:36:14,005
Ooh, Mum can only watch.

364
00:36:37,153 --> 00:36:38,237
[grunting]

365
00:36:38,321 --> 00:36:40,531
[rustling]

366
00:36:42,241 --> 00:36:44,243
[tense music plays]

367
00:37:00,343 --> 00:37:03,930
But the kangaroo gods
are smiling on this little joey.

368
00:37:08,768 --> 00:37:11,229
So long as his luck holds,

369
00:37:12,104 --> 00:37:15,650
he'll spend another year in Mum's care.

370
00:37:24,659 --> 00:37:30,248
Though the day comes when all marsupials
have to leave the protection of the pouch.

371
00:37:44,470 --> 00:37:49,558
Now 15 months old,
joey's taken a big leap forward.

372
00:37:52,436 --> 00:37:55,231
He spends his days
sparring with his peers.

373
00:37:55,815 --> 00:38:00,027
[grunting]

374
00:38:04,156 --> 00:38:06,325
[grunting]

375
00:38:07,076 --> 00:38:09,495
Mum's pouch has been taken over…

376
00:38:11,539 --> 00:38:12,540
by a sister.

377
00:38:16,294 --> 00:38:20,715
She's just six months old,
and hasn't set foot outside.

378
00:38:27,096 --> 00:38:30,975
[howling]

379
00:38:31,058 --> 00:38:34,145
But roos aren't the only ones
in the valley with young.

380
00:38:35,229 --> 00:38:36,939
[barking]

381
00:38:38,858 --> 00:38:39,775
[barking]

382
00:38:41,944 --> 00:38:46,032
The dingo pack
have left their pups to go hunting.

383
00:38:55,708 --> 00:39:01,505
Early human settlers introduced dingoes
to Australia around 3,500 years ago.

384
00:39:08,262 --> 00:39:12,850
Since then, they've become
the grey kangaroo's worst enemy.

385
00:39:23,235 --> 00:39:25,237
Other youngsters head for safety.

386
00:39:28,074 --> 00:39:29,825
But joey's got nowhere to go.

387
00:39:30,659 --> 00:39:33,496
[tense music playing]

388
00:39:36,707 --> 00:39:37,541
[grunting]

389
00:39:39,335 --> 00:39:42,880
If he can't keep up with the mob,
he's in trouble.

390
00:39:49,970 --> 00:39:51,972
[dramatic music plays]

391
00:39:54,558 --> 00:39:55,893
[growling]

392
00:40:03,859 --> 00:40:04,860
[growling]

393
00:40:15,413 --> 00:40:17,706
-The dingoes rush the roos…
-[dingoes howling]

394
00:40:19,375 --> 00:40:20,960
…searching for the slow.

395
00:40:22,294 --> 00:40:25,423
[grunting]

396
00:40:26,257 --> 00:40:28,259
[dramatic music continues]

397
00:40:38,727 --> 00:40:40,020
[grunting]

398
00:40:44,859 --> 00:40:48,028
A heavily-laden Mum is lagging behind.

399
00:40:48,112 --> 00:40:49,488
[shrieking]

400
00:40:52,158 --> 00:40:54,160
[suspenseful music plays]

401
00:41:02,209 --> 00:41:03,669
The hunters close in.

402
00:41:06,088 --> 00:41:08,090
[dramatic music plays]

403
00:41:20,144 --> 00:41:20,978
[grunt]

404
00:41:29,320 --> 00:41:30,321
[squealing]

405
00:41:37,620 --> 00:41:40,998
Fewer than half of all joeys
make it to adulthood.

406
00:41:47,296 --> 00:41:50,299
But on the far side of the valley,

407
00:41:50,966 --> 00:41:54,595
joey, Mum and his sister
have all survived.

408
00:41:58,766 --> 00:42:00,935
With pioneering spirit,

409
00:42:01,519 --> 00:42:03,896
amazing adaptability

410
00:42:04,480 --> 00:42:08,817
and, let's face it, not much competition,

411
00:42:09,735 --> 00:42:12,863
Australia's marsupials
have risen to the challenges

412
00:42:12,947 --> 00:42:15,074
of this unforgiving land.

413
00:42:18,869 --> 00:42:22,331
But this wonderful collection
of eccentric animals

414
00:42:22,414 --> 00:42:26,168
is struggling to adapt
to the threat of new predators…

415
00:42:26,252 --> 00:42:27,920
[howling]

416
00:42:28,003 --> 00:42:30,548
…and the chaos of climate change.

417
00:42:40,140 --> 00:42:42,893
But there are some
who are fighting for their future.

418
00:42:46,480 --> 00:42:51,527
Across Australia, people are devoting
their lives to rescuing…

419
00:42:53,779 --> 00:42:54,905
releasing…

420
00:43:00,035 --> 00:43:03,914
and protecting
the marsupials most in need.

421
00:43:03,998 --> 00:43:06,375
[hopeful music plays]

422
00:43:17,761 --> 00:43:21,140
And some species
are proving remarkably resilient.

423
00:43:22,558 --> 00:43:26,437
Eastern grey kangaroos
still thrive in their millions.

424
00:43:28,480 --> 00:43:30,357
Thanks to the might of the mob,

425
00:43:30,941 --> 00:43:33,152
one seriously dedicated mum

426
00:43:34,278 --> 00:43:36,030
and her amazing pouch,

427
00:43:36,989 --> 00:43:39,450
joey's had a great start.

428
00:43:41,660 --> 00:43:43,078
Now it's time to grow up.

429
00:43:43,787 --> 00:43:44,913
[grunting]

430
00:43:46,749 --> 00:43:47,958
And just maybe,

431
00:43:49,251 --> 00:43:50,669
maybe one day,

432
00:43:51,670 --> 00:43:53,922
become a kangaroo king.

433
00:43:57,092 --> 00:44:00,179
[closing theme music playing]