1
00:00:04,280 --> 00:00:08,840
There was a time when myths and science were entwined...

2
00:00:10,520 --> 00:00:15,160
..when mermaids and unicorns could mysteriously appear.

3
00:00:15,160 --> 00:00:17,680
Nature was weird.

4
00:00:19,640 --> 00:00:23,960
When science revealed the truth behind these imaginary creatures,

5
00:00:23,960 --> 00:00:28,240
it found real animals lay behind the legends.

6
00:00:29,720 --> 00:00:34,760
Today, science still makes astonishing discoveries,

7
00:00:34,760 --> 00:00:37,640
but nature seems just as weird.

8
00:00:37,640 --> 00:00:42,240
It's just that fact has broken free from fiction.

9
00:00:53,520 --> 00:00:56,600
GROWLING

10
00:01:01,120 --> 00:01:05,160
In nature, a good defence is key to survival.

11
00:01:06,160 --> 00:01:10,320
But humans have no natural defences at all.

12
00:01:12,320 --> 00:01:17,760
Even our most magical camouflage is no match for the real thing.

13
00:01:25,160 --> 00:01:28,360
Vine snakes freeze motionless for hours

14
00:01:28,360 --> 00:01:31,720
as they mimic the creepers that hide them.

15
00:01:39,160 --> 00:01:41,720
In turn, snakes are impersonated

16
00:01:41,720 --> 00:01:44,280
by the snakehead caterpillar.

17
00:01:52,720 --> 00:01:57,560
Insects become leaves, finessed with details of damage.

18
00:02:01,120 --> 00:02:04,920
A hunter's spotted coat conjures up dappled shade.

19
00:02:09,000 --> 00:02:13,000
But in the arms race between predator and prey,

20
00:02:13,000 --> 00:02:17,040
even the eyes of a killer are mimicked.

21
00:02:24,000 --> 00:02:28,040
These false faces, complete with eyes and nose,

22
00:02:28,040 --> 00:02:30,600
belong to eyespot frogs.

23
00:02:30,600 --> 00:02:33,160
They frighten real predators.

24
00:02:38,480 --> 00:02:42,320
Poison arrow frogs really are lethal.

25
00:02:42,320 --> 00:02:45,720
So rather than hide, they use vivid colours

26
00:02:45,720 --> 00:02:48,880
to warn against being eaten by mistake.

27
00:02:49,880 --> 00:02:53,920
Their toxic secretions lace tribal darts.

28
00:02:53,920 --> 00:02:58,160
The poison from just one frog can kill a man.

29
00:03:02,960 --> 00:03:07,720
Weird Nature uses imaginary settings to showcase real animal behaviour.

30
00:03:14,640 --> 00:03:16,680
This weird journey reveals

31
00:03:16,680 --> 00:03:20,200
the strange ways animals protect themselves.

32
00:03:38,520 --> 00:03:43,080
Full body armour is often the first line of defence.

33
00:03:44,960 --> 00:03:49,480
The three-banded armadillos of Argentina are the masters.

34
00:03:49,480 --> 00:03:51,320
Like medieval knights,

35
00:03:51,320 --> 00:03:53,840
they use articulated armour.

36
00:03:53,840 --> 00:03:58,920
Their protective shields, made from a double layer of horn and bone,

37
00:03:58,920 --> 00:04:01,480
are hinged with leathery skin.

38
00:04:01,480 --> 00:04:05,880
The plates cope with most of what nature throws at them,

39
00:04:05,880 --> 00:04:08,480
but a polo match is exceptional.

40
00:04:15,080 --> 00:04:20,320
This imaginary scene showcases the armadillo's extraordinary behaviour.

41
00:04:30,720 --> 00:04:35,840
Its first defence is to run, but heavy armour slows it down.

42
00:04:36,960 --> 00:04:39,960
Its second defence is to roll up,

43
00:04:39,960 --> 00:04:44,280
interlocking its plates into a sealed ball...

44
00:04:48,560 --> 00:04:51,680
..the strongest shape in nature.

45
00:04:59,440 --> 00:05:04,760
It can open just a chink to check what's happening.

46
00:05:13,360 --> 00:05:16,000
Even WE ball up for protection.

47
00:05:17,480 --> 00:05:22,520
But helmets and padding can't compete with full body armour.

48
00:05:23,520 --> 00:05:28,480
The only soft part of the armadillo is its face and underbelly.

49
00:05:29,560 --> 00:05:34,080
Otherwise, it's a walking armoured tank.

50
00:05:34,080 --> 00:05:39,520
It takes the knocks of real life just as easily in its stride.

51
00:06:02,160 --> 00:06:07,440
This fantasy wreck displays the inventive defences of sea creatures.

52
00:06:11,600 --> 00:06:16,560
The puffer fish has its own version of armour.

53
00:06:20,240 --> 00:06:23,040
Instead of scales,

54
00:06:23,040 --> 00:06:26,680
its leathery skin is armed with spines.

55
00:06:29,720 --> 00:06:33,960
The spines erect to form a lethal pincushion

56
00:06:33,960 --> 00:06:36,760
when the fish sucks in water.

57
00:06:41,640 --> 00:06:46,960
With elasticated skin and no ribs to stop its body expanding,

58
00:06:46,960 --> 00:06:51,520
it balloons to five times its normal size -

59
00:06:51,520 --> 00:06:54,080
too big for most mouths to swallow.

60
00:06:54,080 --> 00:06:58,880
The puffer's ultimate weapon is poison -

61
00:06:58,880 --> 00:07:01,440
enough to kill 30 people.

62
00:07:01,440 --> 00:07:04,040
There is no known antidote.

63
00:07:14,480 --> 00:07:18,680
This wreck also shows how animal defences can adapt

64
00:07:18,680 --> 00:07:21,560
to extraordinary circumstances.

65
00:07:25,560 --> 00:07:30,600
For dresser crabs, the right dress code is everything.

66
00:07:30,600 --> 00:07:34,440
They decorate their shells to fit in

67
00:07:34,440 --> 00:07:37,240
wherever they go.

68
00:07:37,240 --> 00:07:41,360
They select material from whatever is around.

69
00:07:41,360 --> 00:07:45,400
A dressing room full of treasure is paradise.

70
00:07:45,400 --> 00:07:50,640
They first chew their finds to make them frayed and fibrous.

71
00:07:50,640 --> 00:07:56,520
They then attach the prepared fabrics to Velcro-like hooks

72
00:07:56,520 --> 00:07:59,080
on their legs and shell.

73
00:08:00,640 --> 00:08:04,960
The dresser crab uses its keen attention to detail

74
00:08:04,960 --> 00:08:07,680
to fashion a camouflaged suit.

75
00:08:14,240 --> 00:08:19,080
It usually adorns its costume with sponges and seaweed,

76
00:08:19,080 --> 00:08:21,800
as these are most often to hand.

77
00:08:23,960 --> 00:08:26,960
But given the chance, it improvises,

78
00:08:26,960 --> 00:08:32,280
a trait that helps the dresser crab maintain perfect camouflage.

79
00:08:51,480 --> 00:08:55,840
Their eclectic dress sense means they blend in anywhere,

80
00:08:55,840 --> 00:09:00,760
safe from they eyes of predators like puffer fish.

81
00:09:07,960 --> 00:09:10,520
To vanish, they freeze.

82
00:09:27,640 --> 00:09:31,600
Making yourself bigger is not only a defence -

83
00:09:31,600 --> 00:09:33,960
it can also send a message.

84
00:09:38,520 --> 00:09:44,160
The spotted skunk is famed for its offensive body odour.

85
00:09:49,160 --> 00:09:52,440
TECHNO MUSIC

86
00:09:52,440 --> 00:09:57,720
Bold markings warn that it carries a concealed weapon.

87
00:10:10,640 --> 00:10:15,200
If the skunk isn't shown respect, it ups the ante.

88
00:10:20,840 --> 00:10:26,520
Handstanding exaggerates its size and shows off its markings.

89
00:10:31,040 --> 00:10:33,760
It's a dance of defiance.

90
00:10:36,360 --> 00:10:40,920
Foot-stomping drives home the threat.

91
00:10:45,000 --> 00:10:49,920
If the message is missed, the skunk reveals its weapon.

92
00:10:52,520 --> 00:10:57,480
Like an aerosol, anal glands spray sulphurous chemicals

93
00:10:57,480 --> 00:11:00,520
through nozzles aimed at the eyes.

94
00:11:00,520 --> 00:11:04,560
They cause temporary blindness and nausea.

95
00:11:16,840 --> 00:11:19,720
Some defensive sprays are even deadlier.

96
00:11:30,720 --> 00:11:32,520
Most give cobras

97
00:11:32,520 --> 00:11:34,240
a wide berth.

98
00:11:35,640 --> 00:11:40,360
But they say curiosity killed the cat.

99
00:11:50,400 --> 00:11:54,440
Snakes prefer to conserve their venom.

100
00:12:02,560 --> 00:12:05,760
So it spreads its hood as a warning.

101
00:12:11,920 --> 00:12:14,640
The spitting cobra aims for the eyes.

102
00:12:18,000 --> 00:12:22,320
Glands squeeze venom through hypodermic fangs.

103
00:12:27,760 --> 00:12:30,640
The spray jets 3m.

104
00:12:31,960 --> 00:12:36,000
A direct hit could have blinded for life.

105
00:12:39,640 --> 00:12:42,680
Most animals fear snakes.

106
00:12:42,680 --> 00:12:47,120
The horned frog of Central America is no exception.

107
00:12:51,480 --> 00:12:55,840
A lookalike snake provokes the same bizarre reaction.

108
00:12:55,840 --> 00:12:58,840
LOUD SCREECH

109
00:13:06,680 --> 00:13:11,960
If puffing up and screaming like a banshee fails, it fights back.

110
00:13:19,800 --> 00:13:24,480
It pays to have a wide repertoire. Danger is never far away.

111
00:13:29,480 --> 00:13:33,320
A horned owl would soon make a meal of a frog,

112
00:13:33,320 --> 00:13:35,640
even one with an inflated ego.

113
00:14:01,360 --> 00:14:06,360
But owls are equally fooled by a snake in the grass.

114
00:14:09,880 --> 00:14:12,560
They click their beaks and hiss and arch their wings

115
00:14:12,560 --> 00:14:14,480
to puff themselves up.

116
00:14:17,400 --> 00:14:20,400
If this bluff fails, they turn tail.

117
00:14:40,520 --> 00:14:44,360
Changing shape has been perfected by many sea creatures.

118
00:15:05,600 --> 00:15:11,120
The octopus's soft, malleable body helps it change shape easily,

119
00:15:11,120 --> 00:15:16,640
but the price of having no skeleton is vulnerability.

120
00:15:19,160 --> 00:15:24,200
One defence is to change texture to mimic its surroundings.

121
00:15:28,200 --> 00:15:30,880
Another is reactive camouflage.

122
00:15:32,080 --> 00:15:37,640
Its near-instantaneous colour change is under nervous control.

123
00:15:37,640 --> 00:15:41,000
Pigment cells expand and contract

124
00:15:41,000 --> 00:15:43,680
in waves of emotion.

125
00:15:48,960 --> 00:15:54,040
The colour cells react quicker than those of any other animal.

126
00:15:59,960 --> 00:16:04,440
But this quick-change artist has a rival.

127
00:16:17,640 --> 00:16:19,720
The peacock flounder's skin

128
00:16:19,720 --> 00:16:23,720
can make a near perfect facsimile of its surroundings.

129
00:16:33,720 --> 00:16:38,840
A paper-thin profile helps its vanishing trick.

130
00:16:43,200 --> 00:16:47,280
But how does it fare on a less familiar background?

131
00:16:51,480 --> 00:16:55,440
Its stalked eyes have feature detectors,

132
00:16:55,440 --> 00:16:59,680
primed to pick out patterns. It does a quick survey

133
00:16:59,680 --> 00:17:02,240
and then it makes a match.

134
00:17:10,520 --> 00:17:13,120
The eyes pass data to the brain

135
00:17:13,120 --> 00:17:17,240
which adjusts the size and contrast of pigment cells

136
00:17:17,240 --> 00:17:18,840
for the best possible copy.

137
00:17:24,800 --> 00:17:28,880
Incredibly, it has to assume how the pattern would continue

138
00:17:28,880 --> 00:17:30,640
if its body wasn't there.

139
00:17:32,640 --> 00:17:37,040
On familiar ground the match is perfect.

140
00:17:40,960 --> 00:17:44,840
If the octopus' camouflage fails, it has other tactics.

141
00:17:47,000 --> 00:17:50,280
Throwing sand in the face is one.

142
00:17:50,280 --> 00:17:53,160
So is whipping up a smokescreen.

143
00:17:53,160 --> 00:17:58,360
The ink is made of the black pigment, melanin.

144
00:18:03,280 --> 00:18:06,640
It escapes under the cover of darkness.

145
00:18:11,920 --> 00:18:17,240
The octopus's last trick is that of a contortionist.

146
00:18:18,560 --> 00:18:23,080
It can squeeze through a hole one tenth its body width.

147
00:18:25,480 --> 00:18:31,360
Its shrink-to-fit routine is limited only by the size of its beak.

148
00:18:31,360 --> 00:18:34,920
Once these hard mouth parts are through,

149
00:18:34,920 --> 00:18:36,880
the rest is easy.

150
00:18:55,160 --> 00:18:59,760
But the best shape-shifting act belongs to another of its kind.

151
00:19:13,920 --> 00:19:16,280
This is the amazing vampire squid.

152
00:19:18,520 --> 00:19:23,280
This rare, deep-sea octopus has an equally rare defence.

153
00:19:23,280 --> 00:19:26,040
It turns itself inside-out.

154
00:19:30,480 --> 00:19:34,560
The armoury of spines makes it seem impregnable.

155
00:19:36,040 --> 00:19:38,960
But its spines are soft as jelly.

156
00:19:38,960 --> 00:19:43,000
It seems this is just an amazing bluff.

157
00:19:45,800 --> 00:19:50,360
Other creatures of the depths have equally odd defences.

158
00:19:55,240 --> 00:19:56,760
In the cold fjords of Sweden,

159
00:19:56,760 --> 00:20:01,240
crab fishermen occasionally dredge up more than they bargained for.

160
00:20:10,600 --> 00:20:12,960
These are hagfish,

161
00:20:12,960 --> 00:20:16,360
relics from before the age of dinosaurs.

162
00:20:18,640 --> 00:20:23,680
Their peculiar miracle is turning seawater into slime.

163
00:20:25,800 --> 00:20:29,840
Glands that line their body fire out protein pellets

164
00:20:29,840 --> 00:20:33,160
that swell on contact with water.

165
00:20:33,160 --> 00:20:36,080
Other glands fire explosive threads.

166
00:20:36,080 --> 00:20:40,240
Together, they form an impenetrable slime barrier

167
00:20:40,240 --> 00:20:42,640
that suffocates predators.

168
00:20:45,720 --> 00:20:47,760
To avoid the same vile fate,

169
00:20:47,760 --> 00:20:51,440
the hagfish can slip off its slimy coat

170
00:20:51,440 --> 00:20:54,440
by passing a knot down its body.

171
00:20:59,520 --> 00:21:02,600
One hagfish oozes enough gunge

172
00:21:02,600 --> 00:21:06,760
to turn a whole bucket of water into slime.

173
00:21:06,760 --> 00:21:09,440
As well as deterring predators,

174
00:21:09,440 --> 00:21:13,120
this gloopy mucus keeps rival hagfish away,

175
00:21:13,120 --> 00:21:16,480
as they scavenge on rotted carcasses.

176
00:21:33,840 --> 00:21:38,880
Even hungry birds find this slippery fish too slimy to swallow.

177
00:22:01,960 --> 00:22:07,480
In Scandinavia, fieldfares use equally foul play on intruders.

178
00:22:12,280 --> 00:22:17,600
Fieldfares nest together, so one alarm call rallies the whole colony.

179
00:22:17,600 --> 00:22:20,600
LOW-PITCHED CHIRPING

180
00:22:20,600 --> 00:22:24,360
All who trespass are dealt the same dirty trick.

181
00:22:44,960 --> 00:22:48,880
Even though humans have little natural protection,

182
00:22:48,880 --> 00:22:52,600
we've made up for it with some deadly inventions.

183
00:22:56,760 --> 00:23:01,200
But these birds have their own fire power.

184
00:23:10,560 --> 00:23:13,720
GUNSHOT

185
00:23:13,720 --> 00:23:16,880
The whole squadron is scrambled.

186
00:23:23,560 --> 00:23:28,400
The hunter gets his comeuppance. On birds of prey the droppings

187
00:23:28,400 --> 00:23:33,720
can be fatal, destroying the waterproofing of their plumage.

188
00:23:33,720 --> 00:23:38,680
The fulmar's defence tactics are even more repulsive.

189
00:23:40,720 --> 00:23:43,520
Its frontline defence is a mountain fortress

190
00:23:43,520 --> 00:23:46,680
that keeps land predators from the breeding colony.

191
00:23:50,520 --> 00:23:53,720
The young are left for hours on these sea stacks

192
00:23:53,720 --> 00:23:58,080
as their parents make long fishing trips far offshore.

193
00:24:01,600 --> 00:24:04,640
Wise climbers avoid nesting cliffs.

194
00:24:04,640 --> 00:24:08,160
They know that chicks left home alone have a secret weapon.

195
00:24:10,920 --> 00:24:15,480
But what happens if a climber takes the wrong route?

196
00:24:15,480 --> 00:24:20,520
Chicks brew up an oily concoction in their stomachs from fish they eat.

197
00:24:24,000 --> 00:24:29,440
They save this vile soup for the times they're left alone.

198
00:24:29,440 --> 00:24:33,960
The chicks' usual threat is predatory birds,

199
00:24:33,960 --> 00:24:37,640
but anything within spitting distance becomes a target.

200
00:24:37,640 --> 00:24:41,640
It fires a warning shot, followed by a blast.

201
00:24:54,280 --> 00:24:56,160
The vomit is made from fish oils,

202
00:24:56,160 --> 00:24:59,600
separated in the stomach from other food.

203
00:25:00,720 --> 00:25:06,240
What repels a climber could kill a bird. The vomit also damages plumage,

204
00:25:06,240 --> 00:25:09,440
causing hypothermia or drowning.

205
00:25:12,360 --> 00:25:16,760
Birds that use projectile vomiting may seem bizarre.

206
00:25:19,960 --> 00:25:25,200
But humans are weirder. We evolved to have no natural defences at all.

207
00:25:35,320 --> 00:25:38,000
Our safety net is our technology

208
00:25:38,000 --> 00:25:42,040
and a brain that quickly learns from mistakes.

209
00:25:49,400 --> 00:25:54,880
Few animals are so poorly equipped to defend themselves.

210
00:25:54,880 --> 00:25:58,920
In nature's terms, it is WE who are weird.

211
00:26:18,600 --> 00:26:23,280
Other animals even employ acting skills as a defence.

212
00:26:28,200 --> 00:26:31,000
This is not what it seems.

213
00:26:31,000 --> 00:26:33,920
These animals are far from dead.

214
00:26:41,280 --> 00:26:45,360
They are putting on a remarkable performance.

215
00:26:51,160 --> 00:26:55,720
Only a hint of movement gives the game away.

216
00:27:00,200 --> 00:27:04,760
Birds enter this trance-like state quite readily.

217
00:27:07,960 --> 00:27:12,960
Frogs appear to die if turned on their backs,

218
00:27:12,960 --> 00:27:15,520
but it's just a bluff.

219
00:27:18,560 --> 00:27:23,160
The hognose snake lolls its tongue to fake death throes

220
00:27:23,160 --> 00:27:26,000
and gives off the stench of decay.

221
00:27:27,480 --> 00:27:32,160
The opossum gave death-feigning a name.

222
00:27:32,160 --> 00:27:33,920
As it plays possum,

223
00:27:33,920 --> 00:27:38,720
anal secretions make it smell like a rotten corpse.

224
00:27:38,720 --> 00:27:41,960
This behaviour is easily triggered

225
00:27:41,960 --> 00:27:44,800
by harmless hypnosis techniques.

226
00:27:44,800 --> 00:27:48,680
Strangely, the animals often wake up together.

227
00:27:53,960 --> 00:27:58,920
Playing dead works because most predators won't touch carrion.

228
00:28:03,720 --> 00:28:07,680
Danger gone, they quietly leave the stage.

229
00:28:14,960 --> 00:28:18,800
Among nature's devious feats of deception,

230
00:28:18,800 --> 00:28:22,480
playing possum must be as weird as it gets.

231
00:28:33,880 --> 00:28:39,280
Our next weird journey looks at the bizarre ways animals breed.