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Finding the perfect partner
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00:00:10,101 --> 00:00:14,404
is tricky business
in the animal kingdom.
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00:00:14,406 --> 00:00:16,806
Males must put on a show.
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00:00:16,808 --> 00:00:19,609
They'll sing and dance
or compete to near death
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00:00:19,611 --> 00:00:23,513
just to win
a female's favor.
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00:00:25,816 --> 00:00:29,953
But females have the final say
in who becomes their companion.
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There's a lot riding on
making a good match.
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this is a potential protector
and family provider.
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But all antics aside,
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00:00:43,335 --> 00:00:47,403
from brief liaisons
to lifetime bonds --
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00:00:47,405 --> 00:00:51,908
when picking a mate, does "love"
ever enter the equation?
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[Wind howling]
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NARRATOR:
The Arctic.
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Millions of square miles
of empty ice.
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Polar bears
are normally solitary.
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00:01:50,268 --> 00:01:51,568
You might think that
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even finding a partner
in this desolate landscape
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would be a challenge.
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00:01:55,540 --> 00:01:58,808
But they have an excellent
sense of smell
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00:01:58,810 --> 00:02:02,845
and can detect another bear
over the horizon.
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00:02:15,759 --> 00:02:17,627
Male bears
can spend weeks
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tracking the scent
of a female
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who will soon be ready
to mate.
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A bear's age and health
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00:02:41,052 --> 00:02:42,719
will affect its scent,
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00:02:42,721 --> 00:02:46,089
and they sniff closely
to size each other up.
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She's choosy.
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She'll raise the cubs alone
for two or three years.
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It's a huge commitment.
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So, it's vital
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to pick a male
who'll give her offspring
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strong and healthy genes.
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She puts him
through his paces.
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He's led up and down
the slopes.
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00:03:16,187 --> 00:03:19,222
She's testing his fitness.
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00:03:33,203 --> 00:03:35,505
As they get to know
each other,
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00:03:35,507 --> 00:03:37,740
they start to play.
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Courtship is
one of the few times
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00:03:49,387 --> 00:03:51,654
that adult animals
play together.
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This slope's rather steep
for the heavier male.
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It's no good,
he can't quite manage it.
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00:04:47,111 --> 00:04:51,547
But she seems to have decided
that he might be the one.
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00:04:51,549 --> 00:04:55,318
Yet he seems to have
lost interest.
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00:05:01,191 --> 00:05:04,961
It's her turn
to do the chasing...
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00:05:04,963 --> 00:05:08,965
and she's got a few tricks
to reignite his passion.
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He rouses himself
for a closer look.
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00:06:02,786 --> 00:06:04,787
Now that
she's reeled him in,
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she goes straight back
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00:06:06,191 --> 00:06:08,457
to giving him
the run-around.
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00:06:12,129 --> 00:06:13,863
Playing hard-to-get
can reveal
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00:06:13,865 --> 00:06:16,999
how fit and strong
potential partners are --
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00:06:17,001 --> 00:06:20,169
a useful strategy,
and not just in polar bears.
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00:06:23,407 --> 00:06:25,608
It's often the females
who do the choosing
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and the males
who have to make
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00:06:27,278 --> 00:06:29,412
all the effort.
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00:06:29,414 --> 00:06:32,415
In the tropical forest
of Papua New Guinea,
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one male is dedicated to making
that all important
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00:06:35,854 --> 00:06:38,054
first impression.
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00:06:38,056 --> 00:06:40,790
The six-plumed bird of paradise
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00:06:40,792 --> 00:06:43,993
begins with
meticulous housework.
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00:06:43,995 --> 00:06:47,029
He obsessively tidies
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00:06:47,031 --> 00:06:49,532
every fallen leaf.
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00:06:53,370 --> 00:06:56,572
He's hard at work
creating a stage
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00:06:56,574 --> 00:06:59,408
for what will be
quite a performance.
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00:07:04,448 --> 00:07:06,649
A few berries
decorate the floor.
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00:07:13,657 --> 00:07:15,925
His final touch
is hardly ever seen.
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00:07:17,961 --> 00:07:21,297
He appears to have found
a bit of old snake skin.
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00:07:21,299 --> 00:07:22,798
Some scientists believe
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00:07:22,800 --> 00:07:24,533
he's trying to add
the scent of a snake
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00:07:24,535 --> 00:07:26,869
to ward off predators.
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00:07:26,871 --> 00:07:29,405
For others,
it's a cleaning cloth,
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00:07:29,407 --> 00:07:32,241
and he's polishing
a perch for a female.
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00:07:44,187 --> 00:07:46,989
Later, he comes up with
a bigger rag
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00:07:46,991 --> 00:07:49,125
and does the same.
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00:07:50,227 --> 00:07:53,496
Only strong, healthy
and well-fed males
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00:07:53,498 --> 00:07:55,898
can afford the time and effort
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00:07:55,900 --> 00:07:59,035
for this most meticulous
preparation,
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00:07:59,037 --> 00:08:02,038
and in theory,
they're the ones with
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00:08:02,040 --> 00:08:03,940
the better genes
to pass on.
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00:08:03,942 --> 00:08:07,009
He'll have
a highly critical audience.
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00:08:07,011 --> 00:08:10,146
So, it's time to rehearse
the main act.
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00:08:10,148 --> 00:08:14,150
[Jazzy score playing over]
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00:09:07,738 --> 00:09:09,338
His dance steps perfected,
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00:09:09,340 --> 00:09:11,741
he's ready to start the show
for real.
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00:09:15,579 --> 00:09:17,113
He spots a female nearby,
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00:09:17,115 --> 00:09:19,415
so quickly goes to get
more berries
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00:09:19,417 --> 00:09:21,317
to tempt her in.
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00:09:27,090 --> 00:09:28,891
Disaster!
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00:09:28,893 --> 00:09:32,895
He's left his polishing rag
on the dance floor!
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It's perfect for her nest!
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00:09:40,004 --> 00:09:43,439
She flies off without even
seeing his dance.
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00:09:43,441 --> 00:09:46,142
He delivers his berries
too late.
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00:09:46,144 --> 00:09:48,944
He never got the chance
to win her heart --
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00:09:48,946 --> 00:09:52,181
and she stole
his polishing cloth!
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00:09:52,183 --> 00:09:54,116
Back to work.
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00:09:54,118 --> 00:10:00,122
As fussy females favor
particular attributes,
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they become exaggerated
over generations,
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00:10:03,294 --> 00:10:07,129
leading to ever more elaborate
and extreme displays.
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00:10:09,399 --> 00:10:10,900
They are full of clues
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00:10:10,902 --> 00:10:13,702
as to how good
the male's genes might be.
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[Birds calling]
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It's all
a matter of taste.
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00:10:26,784 --> 00:10:30,319
Different species are attracted
to different features --
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fancy feathers,
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00:10:32,757 --> 00:10:36,325
red faces,
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00:10:36,327 --> 00:10:39,728
blue faces...
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00:10:39,730 --> 00:10:43,399
large noses...
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Beauty is all in
the eye of the beholder.
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00:10:54,678 --> 00:10:57,847
It's often a special costume,
or dance,
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00:10:57,849 --> 00:11:02,151
or even an exotic perfume
that can turn heads.
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00:11:02,153 --> 00:11:07,189
In the forests of Madagascar,
it's all three.
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00:11:07,191 --> 00:11:09,892
Welcome to
the lemur lounge bar.
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The boys are on parade,
hoping to be chosen.
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They are sizing each other up
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this morning,
with calculated disdain.
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One of the females
is in heat.
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The breeding season is short
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and who gets whom
is all up for grabs.
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Fights quickly break out.
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The object of their affection
just sits and waits.
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While the fur flies,
one sneaky young male
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sees an opportunity
to make his move.
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He hopes to win her heart
by more subtle means.
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With an air of nonchalance,
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he settles down
and begins to smear scent
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onto his tail
from glands on his wrist.
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00:12:51,328 --> 00:12:53,629
The perfume
he wafts over her
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will tell her a lot about
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00:12:55,466 --> 00:12:58,567
what he has to offer
as a potential partner.
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And he might just
offer something
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that the other males don't.
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He may not be
the strongest fighter,
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but the latest science suggests
his scent might contain clues
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to a different strength --
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00:13:21,225 --> 00:13:24,860
his ability to fight illness
and parasites,
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which he could pass on
to her offspring.
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She's still not convinced.
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Maybe she should wait for
the arguing males to finish.
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[Male lemurs squabbling]
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But the quarrelling continues,
unresolved.
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So, she leads him off
somewhere quieter.
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His offer has finally
won her over,
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and they indulge in
some undercover love.
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00:14:20,584 --> 00:14:23,519
Extravagant dance,
flashy colors
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and irresistible perfume
may all be clues
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00:14:26,090 --> 00:14:27,389
to good genes,
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00:14:27,391 --> 00:14:31,827
but occasionally
a male has to offer more.
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On the other side
of the world,
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an idyllic
English riverside
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is the setting for
one such story.
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00:14:48,178 --> 00:14:51,747
Here is a creature
who seems to flirt with suicide
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00:14:51,749 --> 00:14:54,717
to woo his paramour
with the perfect gift.
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The delicate
banded demoiselle
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knows that what every girl wants
is fast-flowing water,
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rich in life-giving oxygen,
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as the best place
to lay her eggs.
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00:15:06,964 --> 00:15:10,332
Each male,
in his shining metallic armor,
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00:15:10,334 --> 00:15:13,602
is prepared to fight for
the best patch,
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00:15:13,604 --> 00:15:16,038
in a graceful aerial
contretemps.
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00:16:02,952 --> 00:16:05,621
The victor has won
possession of a place
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where the river riffles round
a fallen branch.
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Faster running water --
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that's just what the ladies
are looking for.
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But how can he prove that
this is a good spot?
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He flings himself
at the water,
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using his own body
to show the flow.
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It's a high risk strategy --
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he might drown,
or be snatched by
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a hungry fish.
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If she's impressed,
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she'll allow the seduction
to conclude.
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All his hard work
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has paid off.
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She gives their eggs
the best possible start in life,
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laid on plants
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in oxygen-rich water.
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He's a true romantic hero
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00:17:15,960 --> 00:17:17,559
who's risked his life,
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and all to offer a lady
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00:17:19,263 --> 00:17:21,763
the perfect place
to lay her eggs.
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But there are times
when males offer something
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that seems
almost arbitrary.
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Topi, African antelopes,
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gather each year
for a very unusual
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00:17:40,784 --> 00:17:44,686
and highly ritualized
contest.
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00:17:50,927 --> 00:17:53,262
The males start
by putting on war-paint.
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By plastering their horns
with mud,
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they're trying to be more
intimidating to other males,
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and maybe more attractive
to females.
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The dirtier the better.
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The males compete
in a loose circle,
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called a lek,
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and each fights to hold ground
as close as possible
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to the center of
the arena.
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Gaining a coveted place
on the lek
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signals that a male
is fit enough
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to out-compete
the others.
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00:18:42,079 --> 00:18:45,514
He's stronger,
more determined --
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00:18:45,516 --> 00:18:47,382
a winner.
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00:18:53,723 --> 00:18:56,658
The lek is
a constant battlefield
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00:18:56,660 --> 00:18:58,393
for the duration of
the mating season
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as males continually
challenge and defend.
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00:19:00,598 --> 00:19:03,031
The females
are most impressed
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00:19:03,033 --> 00:19:06,168
with the males
at the heart of the arena,
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00:19:06,170 --> 00:19:07,736
and reward them accordingly.
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00:19:15,144 --> 00:19:18,947
The topis' rituals
go on for many days.
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00:19:18,949 --> 00:19:21,416
The males dare not leave
their territories,
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00:19:21,418 --> 00:19:22,884
or rivals
will claim them.
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00:19:22,886 --> 00:19:25,387
As the days pass,
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00:19:25,389 --> 00:19:27,623
they become
ever more exhausted.
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00:20:03,126 --> 00:20:06,194
For some,
the competition exacts
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00:20:06,196 --> 00:20:08,397
the ultimate price.
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00:20:11,000 --> 00:20:12,501
Hyenas are quick
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00:20:12,503 --> 00:20:15,203
to take advantage of
the weak and exhausted topi,
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00:20:15,205 --> 00:20:18,306
particularly on the edges.
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00:20:21,344 --> 00:20:23,378
We can see now
why the females
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00:20:23,380 --> 00:20:25,580
find the topi in the middle
more attractive.
218
00:20:25,582 --> 00:20:29,184
The center is very much
worth fighting for.
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00:20:51,641 --> 00:20:53,642
Yet despite the hyenas,
220
00:20:53,644 --> 00:20:57,245
the male topi stay close to
their positions on the lek.
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00:20:57,247 --> 00:21:00,415
To flee would mean losing
any chance of mating.
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00:21:16,632 --> 00:21:19,267
[Hyenas squabbling]
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00:21:23,406 --> 00:21:27,075
To make sure that they win
any contest with their rivals,
224
00:21:27,077 --> 00:21:29,411
many males weapon up.
225
00:21:29,413 --> 00:21:37,986
[Bellowing]
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00:21:37,988 --> 00:21:40,789
Full of testosterone
and belligerence,
227
00:21:40,791 --> 00:21:43,558
males push each other
to the limit.
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00:22:15,992 --> 00:22:20,362
But fighting is a dangerous,
even life-threatening, strategy.
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00:22:20,364 --> 00:22:22,564
So, animals will go to great
lengths to avoid a fight
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00:22:22,566 --> 00:22:23,965
if they can.
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00:22:23,967 --> 00:22:27,836
American bison
graze peacefully together
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00:22:27,838 --> 00:22:31,306
until the mating
season arrives,
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00:22:31,308 --> 00:22:33,441
when the atmosphere changes.
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00:22:33,443 --> 00:22:35,343
The males begin to
235
00:22:35,345 --> 00:22:38,313
"taste" the air,
to pick up the scent
236
00:22:38,315 --> 00:22:41,449
of any female who might be
ready to mate.
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00:22:43,119 --> 00:22:45,720
Before any fight,
competing males strut
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00:22:45,722 --> 00:22:47,823
alongside each other,
239
00:22:47,825 --> 00:22:50,025
assessing
one another.
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00:22:50,027 --> 00:22:51,760
Pumped up with testosterone,
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00:22:51,762 --> 00:22:54,729
they paw the ground
to show off their strength.
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00:22:54,731 --> 00:22:56,665
They spray the earth
with their urine
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00:22:56,667 --> 00:22:58,300
and then roll in it,
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00:22:58,302 --> 00:23:01,136
so they reek of
their own hormones.
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00:23:14,817 --> 00:23:17,986
These ritual displays
can put off rival males
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00:23:17,988 --> 00:23:22,224
without having to resort to
a potentially dangerous fight.
247
00:23:22,226 --> 00:23:25,727
But it doesn't always work.
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00:23:32,335 --> 00:23:33,902
Even then,
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00:23:33,904 --> 00:23:36,805
most fights are resolved
in a matter of seconds.
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00:23:36,807 --> 00:23:38,340
A few, however,
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00:23:38,342 --> 00:23:40,876
escalate into
full-scale battle.
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00:23:50,987 --> 00:23:52,821
Weighing almost a ton,
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00:23:52,823 --> 00:23:54,556
they use power and speed
254
00:23:54,558 --> 00:23:57,525
to try and push each other
off their feet.
255
00:24:04,634 --> 00:24:08,069
This male is lucky to escape
a fatal stabbing.
256
00:24:11,941 --> 00:24:16,978
For the winner, the prize is
the whole harem of females.
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00:24:19,348 --> 00:24:22,984
Whether by fighting
or by more sophisticated means,
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00:24:22,986 --> 00:24:26,321
it's often males who seem to do
the hard work.
259
00:24:26,323 --> 00:24:30,292
But it's not always as one-sided
as you might think.
260
00:24:37,566 --> 00:24:39,868
In the mountains of
Central Africa
261
00:24:39,870 --> 00:24:42,103
live gorillas.
262
00:24:48,711 --> 00:24:50,178
Extended families
263
00:24:50,180 --> 00:24:51,680
of females
and youngsters
264
00:24:51,682 --> 00:24:53,548
are headed up
by a dominant male,
265
00:24:53,550 --> 00:24:55,450
the silverback.
266
00:24:55,452 --> 00:24:57,118
He defends his territory
267
00:24:57,120 --> 00:25:00,488
by intimidating any rivals
from among his neighbors.
268
00:25:05,995 --> 00:25:07,495
Fights are rare,
269
00:25:07,497 --> 00:25:11,199
and as with bison,
there's a lot of bluster.
270
00:25:17,406 --> 00:25:20,008
Males also hope to impress
neighboring females
271
00:25:20,010 --> 00:25:23,144
with displays of strength,
272
00:25:23,146 --> 00:25:24,646
tempting them to join him,
273
00:25:24,648 --> 00:25:27,048
while keeping
the neighboring silverbacks
274
00:25:27,050 --> 00:25:29,217
well away.
275
00:25:34,056 --> 00:25:35,557
He's attracted
276
00:25:35,559 --> 00:25:37,926
a new young female.
277
00:25:37,928 --> 00:25:40,528
It seems she wants
this silverback
278
00:25:40,530 --> 00:25:42,464
to father
her children.
279
00:25:42,466 --> 00:25:44,265
She only has a day or two
when she's fertile.
280
00:25:44,267 --> 00:25:46,167
There's no time to waste,
281
00:25:46,169 --> 00:25:50,372
but she's going to have to
work hard to get his attention.
282
00:25:55,544 --> 00:25:57,412
She stares at him,
283
00:25:57,414 --> 00:26:01,149
a brazenly flirtatious act
in itself.
284
00:26:01,151 --> 00:26:03,151
She tightens her lips
into a smile
285
00:26:03,153 --> 00:26:06,855
and gazes straight
into his eyes.
286
00:26:09,425 --> 00:26:13,695
This is gorilla seduction
at its least subtle.
287
00:26:36,585 --> 00:26:39,254
But he doesn't seem to be
won over
288
00:26:39,256 --> 00:26:41,056
by her shameless tactics.
289
00:26:41,058 --> 00:26:44,692
Now what's a girl to do?
290
00:26:55,104 --> 00:26:58,773
The whole family watches
to see what happens next.
291
00:27:01,744 --> 00:27:03,912
The young female
decides to try
292
00:27:03,914 --> 00:27:05,613
a different tactic.
293
00:27:05,615 --> 00:27:07,282
There are two teenagers,
294
00:27:07,284 --> 00:27:09,417
black-backed
immature males,
295
00:27:09,419 --> 00:27:13,021
and she flirts with them.
296
00:27:13,023 --> 00:27:15,190
She positions herself between
297
00:27:15,192 --> 00:27:16,591
the two rival boys.
298
00:27:16,593 --> 00:27:18,026
Both are
interested in her.
299
00:27:18,028 --> 00:27:20,128
She's a tease.
300
00:27:20,130 --> 00:27:21,629
As she joins one,
301
00:27:21,631 --> 00:27:25,600
the other watches,
grunting in jealous fury.
302
00:27:25,602 --> 00:27:27,268
She solicits both males,
303
00:27:27,270 --> 00:27:29,971
but doesn't actually
mate with either.
304
00:27:29,973 --> 00:27:32,941
She only has eyes
on the big prize,
305
00:27:32,943 --> 00:27:35,443
and sure enough,
the silverback hears
306
00:27:35,445 --> 00:27:38,113
and comes charging in.
307
00:27:39,882 --> 00:27:41,583
With a little subterfuge,
308
00:27:41,585 --> 00:27:45,086
she gets her man.
309
00:27:45,088 --> 00:27:47,622
[Grunting]
310
00:27:56,232 --> 00:27:57,899
The silverback will offer
311
00:27:57,901 --> 00:28:02,337
more than just good genes
to her offspring.
312
00:28:02,339 --> 00:28:04,005
Any children that are his
313
00:28:04,007 --> 00:28:07,242
will get his protection
as part of the family.
314
00:28:09,512 --> 00:28:12,881
Perhaps best to make
absolutely sure.
315
00:28:22,358 --> 00:28:24,058
It's all for this --
316
00:28:24,060 --> 00:28:27,328
a helpless
mountain gorilla baby,
317
00:28:27,330 --> 00:28:29,898
one of only a handful left.
318
00:28:37,239 --> 00:28:41,075
The family bonds among
mountain gorillas are strong.
319
00:28:45,781 --> 00:28:50,285
The silverback's role as father
goes beyond protection.
320
00:28:50,287 --> 00:28:54,189
He's babysitter,
playmate,
321
00:28:54,191 --> 00:28:56,124
and role model, too.
322
00:29:23,786 --> 00:29:25,520
When both parents stick around
323
00:29:25,522 --> 00:29:27,689
to protect and rear
the offspring,
324
00:29:27,691 --> 00:29:30,725
finding the right mate
becomes more complex.
325
00:29:30,727 --> 00:29:34,195
It's no longer just about
strong and healthy genes,
326
00:29:34,197 --> 00:29:36,698
but more about
being a good father.
327
00:29:39,835 --> 00:29:42,937
Dads offering
worthy parenting skills
328
00:29:42,939 --> 00:29:46,441
can be found in
the most unlikely of places.
329
00:29:50,045 --> 00:29:53,047
Spring in the sea
off Australia.
330
00:29:53,049 --> 00:29:56,084
Below the surface
331
00:29:56,086 --> 00:29:59,921
lies a dedicated father,
a weedy sea dragon.
332
00:30:01,957 --> 00:30:04,792
His outfit is unusual
for a fish,
333
00:30:04,794 --> 00:30:08,463
with colors and dots
and strange attachments.
334
00:30:08,465 --> 00:30:10,932
He's a cousin of
the sea horse.
335
00:30:10,934 --> 00:30:14,602
When he finds
his weedy sea dragoness,
336
00:30:14,604 --> 00:30:17,171
he joins her
for a dance.
337
00:30:22,745 --> 00:30:27,215
As the evening progresses,
she leads him on a slow waltz.
338
00:30:35,424 --> 00:30:38,726
In a graceful duet,
each partner mirrors
339
00:30:38,728 --> 00:30:40,628
the actions of the other.
340
00:30:50,773 --> 00:30:54,409
They sweep and they wiggle.
341
00:31:11,927 --> 00:31:14,595
Darkness will soon draw a veil
over the pair,
342
00:31:14,597 --> 00:31:18,700
but they will dance on
into the night.
343
00:31:25,974 --> 00:31:27,975
Two months later,
344
00:31:27,977 --> 00:31:31,446
and the nature of what he was
offering is revealed.
345
00:31:31,448 --> 00:31:36,484
After the dance, the female
transferred all her eggs to him.
346
00:31:36,486 --> 00:31:39,821
Since then, he alone
has cared for them.
347
00:31:39,823 --> 00:31:44,258
By embedding them in his tail
and carrying them everywhere,
348
00:31:44,260 --> 00:31:48,129
he has kept them safe.
349
00:31:51,467 --> 00:31:55,036
And now,
they start to hatch.
350
00:32:06,982 --> 00:32:10,084
In the calm of
a summer morning,
351
00:32:10,086 --> 00:32:13,187
a baby weedy sea dragon
is born,
352
00:32:13,189 --> 00:32:15,323
its yolk sac still attached.
353
00:32:20,562 --> 00:32:23,064
The babies shelter
in the weed bed,
354
00:32:23,066 --> 00:32:24,632
now feeding themselves.
355
00:32:24,634 --> 00:32:30,238
Their success is thanks to
a father that stayed around.
356
00:32:33,142 --> 00:32:34,642
Many other animals
357
00:32:34,644 --> 00:32:38,346
test for parenting skills
with a pas de deux,
358
00:32:38,348 --> 00:32:42,316
but flamingos go dancing
on a much grander scale.
359
00:32:42,318 --> 00:32:45,253
[Flamingos squawking]
360
00:32:56,064 --> 00:32:59,901
The party here on Lake Bogoria
in Tanzania
361
00:32:59,903 --> 00:33:02,870
is perhaps the greatest
gathering of courting couples
362
00:33:02,872 --> 00:33:04,806
in the animal world.
363
00:33:13,348 --> 00:33:16,350
Thousands of flamingos
dance together,
364
00:33:16,352 --> 00:33:19,353
all looking for
Mister or Missus Right.
365
00:33:31,233 --> 00:33:34,669
Eye color and bright feathers
are important --
366
00:33:34,671 --> 00:33:37,171
the redder,
the better.
367
00:33:43,378 --> 00:33:45,613
Once you've caught
someone's eye,
368
00:33:45,615 --> 00:33:48,649
it's about choosing a partner
who will be loyal,
369
00:33:48,651 --> 00:33:51,419
who will stick around.
370
00:33:51,421 --> 00:33:53,187
Flamingos like partners
371
00:33:53,189 --> 00:33:55,456
of their own
age and size.
372
00:34:01,330 --> 00:34:05,600
But the dance may reveal much
deeper insights into each other.
373
00:34:05,602 --> 00:34:08,469
Many animals
find symmetry attractive,
374
00:34:08,471 --> 00:34:12,240
and the mirrored movements
and coordinated head turns
375
00:34:12,242 --> 00:34:16,177
may help find a mate
that is more compatible.
376
00:34:16,179 --> 00:34:18,913
They seem to prefer birds
like themselves.
377
00:34:32,961 --> 00:34:36,397
It's vital to make
the right choice.
378
00:34:36,399 --> 00:34:38,399
Flamingos nest
379
00:34:38,401 --> 00:34:40,401
in the middle of
soda lakes.
380
00:34:43,438 --> 00:34:46,707
They are swamps
of caustic mud,
381
00:34:46,709 --> 00:34:50,545
and among the hottest
places on Earth.
382
00:34:50,547 --> 00:34:53,414
It's a trek to find
the nearest food and water,
383
00:34:53,416 --> 00:34:55,116
and you can't
leave the nest
384
00:34:55,118 --> 00:34:57,251
to bake in the sun.
385
00:35:01,957 --> 00:35:03,891
That means raising the chick
386
00:35:03,893 --> 00:35:06,427
is impossible
for a single parent,
387
00:35:06,429 --> 00:35:08,963
and working together
is crucial.
388
00:35:08,965 --> 00:35:11,832
It gets above 120°
out here.
389
00:35:11,834 --> 00:35:14,969
This is parenting
at its toughest,
390
00:35:14,971 --> 00:35:20,007
so the choice of partner made in
the dance needs to be right.
391
00:35:43,165 --> 00:35:45,766
There are many animals
for whom the choice of mate
392
00:35:45,768 --> 00:35:47,635
is really about finding
a partner
393
00:35:47,637 --> 00:35:49,537
to look after
the family together.
394
00:35:49,539 --> 00:35:55,710
But in some cases, that doesn't
work out well for everyone.
395
00:35:55,712 --> 00:35:59,246
[Howling]
396
00:35:59,248 --> 00:36:01,682
[Wolves howling]
397
00:36:13,762 --> 00:36:15,730
February in Yellowstone --
398
00:36:15,732 --> 00:36:18,366
bitterly cold
and food is scarce.
399
00:36:18,368 --> 00:36:22,637
Teamwork is what matters
to wolves.
400
00:36:25,440 --> 00:36:26,941
Their prey, elk,
401
00:36:26,943 --> 00:36:30,244
are many times
a wolf's size.
402
00:36:35,317 --> 00:36:37,818
The wolves must work together,
403
00:36:37,820 --> 00:36:41,355
so their offspring stay,
often for years,
404
00:36:41,357 --> 00:36:44,992
hunting, and helping
raise the pups.
405
00:36:44,994 --> 00:36:48,229
This works well
for the wolf parents,
406
00:36:48,231 --> 00:36:50,765
but not quite so well
for their older offspring.
407
00:36:50,767 --> 00:36:53,100
The leading couple discourages
the teenagers
408
00:36:53,102 --> 00:36:55,803
from looking for a mate.
409
00:36:55,805 --> 00:37:00,074
But one of their daughters
has romantic ideas of her own.
410
00:37:00,076 --> 00:37:05,680
Skulking behind the pack
is a lone male wolf.
411
00:37:05,682 --> 00:37:07,415
He has no territory of his own,
412
00:37:07,417 --> 00:37:09,984
but follows the family,
scavenging leftovers
413
00:37:09,986 --> 00:37:13,054
and looking for
opportunities.
414
00:37:13,056 --> 00:37:14,955
He's spotted one --
415
00:37:14,957 --> 00:37:17,558
the young daughter.
416
00:37:22,931 --> 00:37:25,366
The intruder stands
a good chance with her,
417
00:37:25,368 --> 00:37:28,235
as long as
he's not caught.
418
00:37:28,237 --> 00:37:32,006
The pack leader
could kill him.
419
00:37:36,244 --> 00:37:39,780
[Howling]
420
00:37:52,427 --> 00:37:55,796
While the pack is
distracted by a bison,
421
00:37:55,798 --> 00:37:58,332
the temptation
for the young female
422
00:37:58,334 --> 00:38:00,768
is too great,
and she sneaks away
423
00:38:00,770 --> 00:38:03,137
to join
the mysterious stranger.
424
00:38:03,139 --> 00:38:08,309
It's risky, but it could be
her only chance
425
00:38:08,311 --> 00:38:10,311
to hook up with
a potential mate.
426
00:38:41,176 --> 00:38:43,778
When mating,
wolves lock together,
427
00:38:43,780 --> 00:38:47,114
unable to separate
for half an hour,
428
00:38:47,116 --> 00:38:50,017
to ensure fertilization.
429
00:38:50,019 --> 00:38:51,819
Not so good
if you're about to be caught
430
00:38:51,821 --> 00:38:54,021
by your dad.
431
00:38:54,023 --> 00:38:56,056
The affair
was always destined
432
00:38:56,058 --> 00:38:58,359
to be a short one.
433
00:39:29,157 --> 00:39:33,060
After a painful separation,
her new mate is chased away
434
00:39:33,062 --> 00:39:36,096
with his tail
between his legs.
435
00:39:52,080 --> 00:39:54,782
The wayward daughter
is chastised for her behavior.
436
00:39:54,784 --> 00:39:56,317
Eventually though,
437
00:39:56,319 --> 00:39:59,553
she'll be accepted
back into the family.
438
00:40:03,992 --> 00:40:05,860
Had she not been caught,
439
00:40:05,862 --> 00:40:09,363
she could have played
the innocent daughter...
440
00:40:09,365 --> 00:40:11,932
at least until
any pups were born.
441
00:40:11,934 --> 00:40:13,234
It is not unusual
442
00:40:13,236 --> 00:40:16,737
for animals to want their
private lives to remain private.
443
00:40:16,739 --> 00:40:20,841
[Howling]
444
00:40:25,580 --> 00:40:27,381
The more we learn about
how animals behave,
445
00:40:27,383 --> 00:40:29,083
the more it seems that
446
00:40:29,085 --> 00:40:32,486
behind the facade of seemingly
perfect animal partnerships
447
00:40:32,488 --> 00:40:35,189
lurk darker secrets.
448
00:40:35,191 --> 00:40:39,126
The truths of which
are only now coming to light.
449
00:41:03,985 --> 00:41:08,155
Lar gibbons,
in the forests of Thailand.
450
00:41:08,157 --> 00:41:11,558
They seem to be
the perfect couple,
451
00:41:11,560 --> 00:41:13,627
monogamous and musical.
452
00:41:13,629 --> 00:41:16,497
[Calling]
453
00:41:31,546 --> 00:41:33,113
Their duet is
454
00:41:33,115 --> 00:41:35,416
a renewal
of their partnership,
455
00:41:35,418 --> 00:41:37,918
and proclaims
their home territory.
456
00:41:37,920 --> 00:41:39,420
They stay together
457
00:41:39,422 --> 00:41:41,855
to raise a family.
458
00:41:49,030 --> 00:41:50,965
But appearances
459
00:41:50,967 --> 00:41:52,967
can be deceptive.
460
00:41:52,969 --> 00:41:55,202
They're surrounded on all sides
by neighbors,
461
00:41:55,204 --> 00:41:58,973
and gibbons
can sometimes stray.
462
00:41:58,975 --> 00:42:00,474
It turns out
463
00:42:00,476 --> 00:42:04,478
about one in ten matings
is not with their partner.
464
00:42:04,480 --> 00:42:09,616
Some scientists think that
there may be a reason
465
00:42:09,618 --> 00:42:11,185
for a female's infidelity.
466
00:42:11,187 --> 00:42:14,755
A quick liaison may serve to
convince other neighboring males
467
00:42:14,757 --> 00:42:18,926
that they could be
the father of her offspring,
468
00:42:18,928 --> 00:42:21,996
and this might stop them
attacking the youngsters.
469
00:42:21,998 --> 00:42:23,530
Maybe a little infidelity
470
00:42:23,532 --> 00:42:26,967
actually helps
protect the family.
471
00:42:37,846 --> 00:42:40,147
Whatever the reason
for straying,
472
00:42:40,149 --> 00:42:44,118
their affairs don't seem to be
a problem for their partnership.
473
00:42:44,120 --> 00:42:46,320
They'll remain together.
474
00:42:50,859 --> 00:42:52,393
Animals seem to distinguish
475
00:42:52,395 --> 00:42:55,129
the partnership they need
to look after a family
476
00:42:55,131 --> 00:42:57,297
from the affairs
along the way.
477
00:42:57,299 --> 00:43:01,869
But while some animals
tolerate infidelities
478
00:43:01,871 --> 00:43:04,638
and seem to turn
a blind eye,
479
00:43:04,640 --> 00:43:07,174
others notice
and remember.
480
00:43:10,879 --> 00:43:13,447
On the Galapagos Islands,
481
00:43:13,449 --> 00:43:16,116
blue-footed boobies are just
starting their families.
482
00:43:16,118 --> 00:43:21,455
Blue-footed boobies also dance
to form partnerships.
483
00:43:21,457 --> 00:43:25,559
Each movement
mirrors the other.
484
00:43:30,065 --> 00:43:32,099
Like flamingos,
485
00:43:32,101 --> 00:43:34,835
they seem to fall for
birds like themselves --
486
00:43:34,837 --> 00:43:37,004
compatible.
487
00:43:44,145 --> 00:43:46,847
"Booby" means "clown."
488
00:43:46,849 --> 00:43:48,348
Their big blue feet
489
00:43:48,350 --> 00:43:52,953
are an important part
of the costume.
490
00:43:52,955 --> 00:43:56,824
Blue feet are important because
the blue color is hard to make,
491
00:43:56,826 --> 00:43:59,860
especially if the birds
are in poor condition.
492
00:43:59,862 --> 00:44:03,130
It's an honest indicator
of good health.
493
00:44:03,132 --> 00:44:06,200
So, they show them off.
494
00:44:15,276 --> 00:44:16,677
Unlike flamingos,
495
00:44:16,679 --> 00:44:19,913
boobies continue
their courtship displays
496
00:44:19,915 --> 00:44:21,882
even after nesting starts,
497
00:44:21,884 --> 00:44:25,486
as though they weren't
quite sure of each other.
498
00:44:30,391 --> 00:44:32,259
And then,
499
00:44:32,261 --> 00:44:35,295
while their partners
are away feeding,
500
00:44:35,297 --> 00:44:36,997
both sexes flirt with
501
00:44:36,999 --> 00:44:39,733
their neighbors.
502
00:44:42,270 --> 00:44:44,872
The truth is that
boobies have a roving eye,
503
00:44:44,874 --> 00:44:48,275
and those blue feet
tend to wander.
504
00:44:48,277 --> 00:44:49,877
About half have secret,
505
00:44:49,879 --> 00:44:51,678
extra-marital affairs.
506
00:44:51,680 --> 00:44:55,649
They come up to each other
and display.
507
00:45:01,122 --> 00:45:03,423
And one thing
leads to another.
508
00:45:05,160 --> 00:45:08,495
Occasionally,
the male comes back
509
00:45:08,497 --> 00:45:11,331
and sees the female
with someone else.
510
00:45:25,246 --> 00:45:28,115
She quickly
returns to his side.
511
00:45:30,351 --> 00:45:31,818
He doesn't react!
512
00:45:31,820 --> 00:45:33,320
They display,
as they always do,
513
00:45:33,322 --> 00:45:36,590
affirming
their relationship.
514
00:45:36,592 --> 00:45:38,759
They never split up.
515
00:45:48,369 --> 00:45:51,572
It seems here
the instinct to stay together
516
00:45:51,574 --> 00:45:53,073
to raise the family
517
00:45:53,075 --> 00:45:56,877
is stronger than
any infidelity.
518
00:45:56,879 --> 00:46:00,581
But nobody wants to bring up
someone else's chick.
519
00:46:00,583 --> 00:46:06,753
He remembers what he saw
and seems to count the days.
520
00:46:06,755 --> 00:46:08,288
If an egg is laid five days
521
00:46:08,290 --> 00:46:10,791
after catching his partner
with a neighbor,
522
00:46:10,793 --> 00:46:14,194
he knows he isn't the father.
523
00:46:14,196 --> 00:46:16,363
When she's away,
524
00:46:16,365 --> 00:46:19,666
he'll roll it out of the nest
to be lost.
525
00:46:25,440 --> 00:46:29,076
She returns, and their
relationship keeps going.
526
00:46:29,078 --> 00:46:32,412
She'll lay more,
and once the eggs hatch,
527
00:46:32,414 --> 00:46:35,215
they'll settle down
to a faithful
528
00:46:35,217 --> 00:46:38,518
family life.
529
00:46:38,520 --> 00:46:41,588
So, does everyone cheat
at the mating game?
530
00:46:41,590 --> 00:46:44,124
Well, maybe not.
531
00:46:44,126 --> 00:46:46,560
Animals that stay together
forever and remain faithful
532
00:46:46,562 --> 00:46:48,629
are certainly very rare.
533
00:46:51,199 --> 00:46:55,035
But there may be a few
perfect partnerships.
534
00:46:55,037 --> 00:46:57,337
One may be found
in New Caledonia
535
00:46:57,339 --> 00:47:01,174
in the South Pacific.
536
00:47:01,176 --> 00:47:02,643
These are kagus,
537
00:47:02,645 --> 00:47:07,247
flightless birds that stay
together as a couple for life.
538
00:47:16,624 --> 00:47:20,694
Both parents work together
to look after one chick.
539
00:47:20,696 --> 00:47:24,431
This is Dad, pitting his wits
against a worm.
540
00:47:41,416 --> 00:47:43,750
Spot the chick.
541
00:47:47,422 --> 00:47:49,389
The camouflage is effective.
542
00:47:49,391 --> 00:47:54,494
Less effective
is getting the food in.
543
00:48:13,247 --> 00:48:16,216
Feeding babies
can take a lot of patience.
544
00:48:16,218 --> 00:48:19,052
Some of the young
from previous years
545
00:48:19,054 --> 00:48:20,654
stay in the territory
546
00:48:20,656 --> 00:48:22,556
and help defend any chicks
547
00:48:22,558 --> 00:48:25,258
from predators
or neighboring kagus.
548
00:48:27,428 --> 00:48:30,797
[Calling]
549
00:48:33,334 --> 00:48:34,835
Each morning
550
00:48:34,837 --> 00:48:37,671
they spend about 15 minutes
singing together.
551
00:48:37,673 --> 00:48:40,474
They work as a team
and chase away any intruders.
552
00:48:45,613 --> 00:48:47,547
The kagus' relationship is solid
553
00:48:47,549 --> 00:48:49,316
and their bonds of commitment
554
00:48:49,318 --> 00:48:51,485
are passed down
to the offspring,
555
00:48:51,487 --> 00:48:53,086
forming a really strong
556
00:48:53,088 --> 00:48:55,789
family unit.
557
00:48:55,791 --> 00:48:59,526
But the kagus also seem to be
quite the romantics.
558
00:49:04,599 --> 00:49:06,466
Each year the male
559
00:49:06,468 --> 00:49:09,636
rekindles the flame
with this life-long mate.
560
00:49:16,677 --> 00:49:19,279
She's seen it all before,
561
00:49:19,281 --> 00:49:22,015
but it's still important
to remind her.
562
00:49:27,922 --> 00:49:31,491
After all, no one likes to
be taken for granted.
563
00:49:35,229 --> 00:49:37,798
They may be
committed for life,
564
00:49:37,800 --> 00:49:40,867
but it seems
he still wants her to know
565
00:49:40,869 --> 00:49:42,469
that she's
the only one for him.
566
00:49:52,680 --> 00:49:54,548
Throughout the animal kingdom,
567
00:49:54,550 --> 00:49:57,617
the mating game is full
of extraordinary behavior
568
00:49:57,619 --> 00:50:00,187
and surprising
sophistication.
569
00:50:16,337 --> 00:50:17,838
Even fighting
570
00:50:17,840 --> 00:50:20,307
is overlaid with ritual
571
00:50:20,309 --> 00:50:22,209
and sacrifice.
572
00:50:24,846 --> 00:50:26,847
For many animals
it's all about
573
00:50:26,849 --> 00:50:28,682
playing the field.
574
00:50:33,988 --> 00:50:35,589
Some are
carefully chosen
575
00:50:35,591 --> 00:50:37,824
for a brief liaison.
576
00:50:45,366 --> 00:50:48,668
But there are those
searching for commitment,
577
00:50:48,670 --> 00:50:52,539
a partner who will
stick around.
578
00:50:52,541 --> 00:50:56,776
While others form bonds
that can last a lifetime.
579
00:50:56,778 --> 00:51:01,047
There are even a few
that remain truly faithful.
580
00:51:04,218 --> 00:51:09,689
Though we can never be sure
what animals feel,
581
00:51:09,691 --> 00:51:11,591
sometimes,
582
00:51:11,593 --> 00:51:13,793
it looks like love.
583
00:51:13,795 --> 00:51:16,763
And it's hard
to know, then,
584
00:51:16,765 --> 00:51:18,832
what else to call it.
585
00:51:20,835 --> 00:51:23,703
Back on the soda lake in Africa,
586
00:51:23,705 --> 00:51:26,506
the flamingos
have left their nests.
587
00:51:31,546 --> 00:51:36,383
Left behind,
a couple.
588
00:51:36,385 --> 00:51:38,218
One is stuck,
589
00:51:38,220 --> 00:51:41,254
helpless in the mud.
590
00:51:44,292 --> 00:51:48,094
The other flamingo
could fly away at any point.
591
00:51:48,096 --> 00:51:51,565
The chicks are gone,
their job is done...
592
00:51:51,567 --> 00:51:54,434
but they stay,
593
00:51:54,436 --> 00:51:58,171
together,
to the very end.
594
00:52:40,448 --> 00:52:44,250
To learn more about what you've
seen on this "Nature" program,
595
00:52:44,252 --> 00:52:44,250