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Narrator: We know a leopard
can't change it's spots,
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00:00:03,104 --> 00:00:05,637
But what about giraffes?
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00:00:05,639 --> 00:00:07,606
Midcap: It really does look like
a mythical creature,
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00:00:07,608 --> 00:00:09,441
Where did this come from?
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00:00:09,443 --> 00:00:11,443
Narrator: Why are millions
of birds creating
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Crazy patterns in the sky?
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00:00:13,080 --> 00:00:15,781
But if that was a group of
humans, it would be chaos.
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00:00:15,783 --> 00:00:16,815
Narrator: And if cheetahs
are the worlds
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00:00:16,817 --> 00:00:18,417
Fastest land animals...
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00:00:18,419 --> 00:00:21,220
Everything about these
animals is built for speed.
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00:00:21,222 --> 00:00:23,589
Narrator: ...How come they some
time give up the chase?
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00:00:23,591 --> 00:00:24,990
What the heck is going on?
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00:00:27,294 --> 00:00:30,029
Nature is awe inspiring,
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00:00:30,031 --> 00:00:33,098
But sometimes it just
doesn't make sense.
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00:00:33,100 --> 00:00:35,067
I have never seen
anything like this.
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00:00:35,069 --> 00:00:38,670
Our team of experts investigates
the weirdest animal behavior.
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00:00:38,672 --> 00:00:39,772
It's amazing.
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00:00:39,774 --> 00:00:41,407
Narrator:
And a most unexpected events...
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00:00:41,409 --> 00:00:42,808
What is causing that?
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00:00:42,810 --> 00:00:44,610
Narrator:
...Ever caught on camera.
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Man: My god.
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Narrator: These are...
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August 2017.
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00:00:54,989 --> 00:00:57,923
Ishaqbini hirola conservancy,
kenya.
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Rangers come across
an unusual sight.
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A giraffe and her calf
but neither have any
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Of their signature markings.
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Baker:
Well, this clip is phenomenal,
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I mean to see
a pure white version
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Of anything
that shouldn't be white
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Is always incredible.
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Midcap: So this isn't just a
giraffe with faded
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Coat coloration,
this thing is white.
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Tall, beautiful, looks like
it's in perfect health.
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It really does look like
a mythical creature,
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Where did this come from?
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Narrator:
To find out what's going on,
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We need to know more
about the regular giraffes
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We're used to seeing.
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Burke: Giraffes are famous for
being these long=necked,
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Long-legged, graceful animals.
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And more than anything
their pattern as well,
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Is very, very distinctive.
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Narrator: Giraffe species
have varied markings
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But the reason
for these patterns
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Has been puzzling
scientists for some time.
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Burke: The darker patches
actually have more blood vessels
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Than the lighter patches.
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00:02:02,423 --> 00:02:04,656
And we think this might
have something to do
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With dissipating heat.
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00:02:07,228 --> 00:02:09,361
But it could also have to
do with releasing pheromones
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00:02:09,363 --> 00:02:13,165
As well to attract
mates for example.
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00:02:13,167 --> 00:02:14,399
But there's other theories
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That the reticulated
pattern breaks up
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The outline of the
animal, it just breaks up
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Any lines and possibly
works as camouflage.
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Narrator:
As with other animal patterns
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It's slightly a combination
of all these things
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That give the giraffe
their unique markings.
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00:02:30,918 --> 00:02:37,856
But how is it these ones
have no color at all?
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Midcap: Could it be that this
giraffe is albino?
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Albinism is a condition
where one or more traits
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Are handed down to an
animal that prevents melanin
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From being produced
in the organs.
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Narrator: Melanin is the pigment
that gives skin,
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Hair, and eyes their color
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00:02:58,679 --> 00:03:01,747
But with albinism
hair and skin is white
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00:03:01,749 --> 00:03:04,716
And the eyes are pink as the
blood vessels in the iris
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Have no pigment to mask them.
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So the coat of a giraffe
would depend on the production
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Of melanin
if you were to see all
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Those beautiful colorations
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But in this case
there aren't any.
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Albino creatures can be found
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Across a vast spectrum
of the animal kingdom.
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From white moose,
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To white wallabys,
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To white barracuda.
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So it's quite prevalent,
although it is
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A fairly rare condition,
it does affect the majority
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Of the animal kingdom.
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So I guess the simply
conclusion would be,
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Oh, it's an albino giraffe,
isn't that exciting,
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End of story.
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But actually if you look
closely, this giraffe
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Doesn't have the pink eyes,
it actually has dark eyes,
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So it's not an albino.
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Narrator:
An albino giraffe is ruled out
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So what else could have
created this ghostly giant?
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00:04:02,943 --> 00:04:05,210
Burke: There's another
explanation as to why
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This white giraffe exists,
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And it's a skin disorder
called vitiligo.
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00:04:10,084 --> 00:04:12,317
And it's a condition
whereby over time,
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The skin is unable
to produce melanin.
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Narrator: With vitiligo the
bodies immune system
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Attack it's own melanin
cells by mistake,
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Gradually creating white skin.
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Midcap: It is very rare in
the human population,
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Only about 1% to 2%
of humans have this.
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But in the animal kingdom
it's even more rare.
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Narrator: Rare, yes,
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But it has been seen
in giraffes before.
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A giraffe that was filmed
in sunburu in kenya
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Had this skin
disorder, vitiligo.
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Midcap: So could it be possible
that this giraffe
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Also has vitiligo just
like it's kenyan cousin?
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Narrator: Her offspring's white
coat makes it unlikely.
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If it was vitiligo you
would expect that youngster
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To start off normal
and get slowly paler.
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Narrator: The fact that this
young calf is white
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Just like it's mother,
rules out vitiligo.
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00:05:04,038 --> 00:05:06,171
But if the giraffes
are not albino
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And don't have vitiligo,
what is the reason
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00:05:08,842 --> 00:05:10,776
For their white color?
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00:05:10,778 --> 00:05:12,511
There's only one real
thing that it could be
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That's left and it's a
beautiful and striking thing
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When it happens, but
it is incredibly rare,
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Which is leucism.
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00:05:18,085 --> 00:05:21,853
So what you've got here
is a leucistic individual.
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00:05:21,855 --> 00:05:23,822
Narrator:
Leucism is a genetic condition
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00:05:23,824 --> 00:05:26,191
Where animals are born
with the loss of some
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00:05:26,193 --> 00:05:27,326
But not all pigment.
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00:05:27,328 --> 00:05:30,329
Eyes and hair can
still have color,
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00:05:30,331 --> 00:05:33,065
But the skin is often very pale.
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00:05:33,067 --> 00:05:36,001
The condition effects as
few as one in a thousand
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00:05:36,003 --> 00:05:38,003
And when you do
see these animals,
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They are unmistakable.
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00:05:40,140 --> 00:05:42,741
I've seen it in deer
population, near where I live.
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00:05:42,743 --> 00:05:44,409
A lot of zoos famously
have white tigers,
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Those are leucistic tigers.
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00:05:46,113 --> 00:05:47,946
And they're still rare
and it still produces
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The most peculiarly
beautiful mutations.
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Narrator: Zoos often adopt
leucistic animals
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As being without pigment
means their chances
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Of survival in the
wild are pretty slim.
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Imagine being a white bird in
a wood full of sparrow hawks
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00:06:01,829 --> 00:06:03,061
You're gonna stand out,
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00:06:03,063 --> 00:06:04,930
You're gonna be
the target number one.
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00:06:04,932 --> 00:06:09,601
Narrator: But coloration isn't
only used for camouflage.
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00:06:09,603 --> 00:06:11,737
Burke: Pigments have
multiple functions,
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The pigments will
sometimes impress mates
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00:06:14,174 --> 00:06:17,142
But really fundamentally
pigments also help
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00:06:17,144 --> 00:06:21,880
To protect from uv
radiation from the sun.
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00:06:21,882 --> 00:06:25,484
So albino snakes for example,
they don't fare very well,
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Partly because they
can't thermo regulate,
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But partly because they're
really exposed to uv radiation.
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Any animal that
relies on pigmentation
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Is quite unusual for them
to survive into adulthood.
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Narrator: So this sighting
of white giraffes
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Is particularly special.
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Midcap: White giraffes are
exceedingly rare.
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We don't know how
many exist in the wild
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And this is only the
second one ever spotted
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In this national park.
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So that's the real
magic in this footage
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Is not only
has this animal survived,
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It's actually got offspring
as well, so it's managed
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To successfully breed.
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Narrator: While the deck may be
stacked against this
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Beautiful and unusual
pair of giraffes,
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So far, they're
beating the odds.
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Burke: For now at least,
this female and her calf
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Are doing really really well.
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♪
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Narrator:
The oxfordshire countryside, uk,
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February 2016.
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Tens of thousands of starlings
have flocked together
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And are flying
in elegant patterns.
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Nelson:
Its like a symphony in the sky.
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It's almost like flowing water.
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It's unlike anything
that you've seen before.
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Aryee: Oh, that's cool.
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It does look like one
entity, one organism.
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I've always amazed at how
intricate and how much
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Of a dance
a murmuration really is.
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I absolutely love them.
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Narrator:
Murmurations, the term used
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00:08:03,150 --> 00:08:04,950
To describe this phenomenon,
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Are seen all over the world.
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But we still don't know
the bigger question
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Which is why?
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Narrator: Around the world, bird
watchers are capturing footage
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Of murmurations, the
gatherings of immense numbers
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Of starlings that fly in
intricate patterns in the sky.
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So the question remains,
why do starlings
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Murmurate in the first place?
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Narrator: To unravel the mystery
of murmurations,
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We need to figure
out how so many birds
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Up to six million,
can move together.
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If that was a group of
humans it would be chaos.
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00:08:50,130 --> 00:08:52,664
Narrator: But it's one starling
mirroring the movements
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Of the surrounding birds
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That keeps the
murmuration on course.
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All you have to do is keep
track of who's in front of you
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Who's to your right,
who's to your left,
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Maybe who's above you.
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00:09:02,242 --> 00:09:04,809
And if those seven
individuals are coordinated
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The whole group moves in unison.
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It's fascinating.
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♪
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00:09:13,387 --> 00:09:15,654
Narrator: And that's not all,
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The staggering speed with which
they respond to each other
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Has also only recently
been discovered.
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00:09:21,562 --> 00:09:25,096
Aryee: A team in rome found that
starlings are able to respond
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00:09:25,098 --> 00:09:27,933
To the movement of another
starling next to it
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00:09:27,935 --> 00:09:31,469
Within a hundred milliseconds,
so that quickly.
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00:09:31,471 --> 00:09:35,574
Nelson: So now we know the
intricacies of a murmuration,
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00:09:35,576 --> 00:09:37,309
But we still don't know
the bigger question,
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00:09:37,311 --> 00:09:40,445
Which is why are so many
birds doing this formation?
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00:09:40,447 --> 00:09:43,048
Narrator: One clue might be
the fact that we often
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00:09:43,050 --> 00:09:46,918
See these formations at dusk,
when the temperatures drop.
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00:09:46,920 --> 00:09:53,792
♪
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00:09:53,794 --> 00:09:56,127
Daly: So some researchers
believe that murmurations
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00:09:56,129 --> 00:09:59,197
Are a signal to other birds
so they can all gather
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00:09:59,199 --> 00:10:02,200
In bigger numbers and be warmer.
216
00:10:02,202 --> 00:10:05,203
Aryee: Temperature to me seems
like a very plausible reason.
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00:10:05,205 --> 00:10:08,707
You know, if you're a tiny
bird, you want to recruit
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00:10:08,709 --> 00:10:12,444
Loads of other starlings
to come and roost with you,
219
00:10:12,446 --> 00:10:15,246
So you can share that body heat.
220
00:10:15,248 --> 00:10:16,648
Narrator:
But murmurations happen
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00:10:16,650 --> 00:10:18,483
At all times of the year,
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00:10:18,485 --> 00:10:22,020
Putting the temperature
theory in doubt.
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00:10:22,022 --> 00:10:23,955
Nelson: The problem is that it's
not that they're murmurating
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00:10:23,957 --> 00:10:25,857
Only on cold days,
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00:10:25,859 --> 00:10:28,893
They're actually murmurating
more on warmer days.
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00:10:28,895 --> 00:10:31,329
So it makes sense that
they're not necessarily
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00:10:31,331 --> 00:10:34,199
Communicating, hey, it's
cold, join their group.
228
00:10:34,201 --> 00:10:39,571
But maybe they are
communicating something else.
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00:10:39,573 --> 00:10:41,906
Narrator: Could this instead be
a sophisticated way
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00:10:41,908 --> 00:10:45,677
Of spreading a message
through the flock?
231
00:10:45,679 --> 00:10:47,178
Nelson: If you've ever stopped
and looked at one
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00:10:47,180 --> 00:10:49,014
Of these murmurations,
you would also hear it,
233
00:10:49,016 --> 00:10:50,582
It's very loud.
234
00:10:50,584 --> 00:10:54,953
[ birds chirping ]
235
00:10:57,457 --> 00:10:59,190
So potentially, they're
tweeting to each other
236
00:10:59,192 --> 00:11:01,326
Where the food is.
237
00:11:01,328 --> 00:11:03,395
Aryee: We see this behavior in
the blue footed booty,
238
00:11:03,397 --> 00:11:06,431
You have a leader as it were,
239
00:11:06,433 --> 00:11:09,768
That let's out a loud
squawk and that then signals
240
00:11:09,770 --> 00:11:11,202
To the other
blue footed boobies
241
00:11:11,204 --> 00:11:12,771
That it's time to feast,
242
00:11:12,773 --> 00:11:16,307
And they all dive
simultaneously into the water.
243
00:11:16,309 --> 00:11:25,450
♪
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00:11:25,452 --> 00:11:27,652
It's thought that this
increases the chances
245
00:11:27,654 --> 00:11:30,155
That each bird is
gonna catch a fish.
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00:11:30,157 --> 00:11:34,893
♪
247
00:11:34,895 --> 00:11:37,495
Narrator: But for starlings,
sharing food information
248
00:11:37,497 --> 00:11:41,132
On such a massive scale
just doesn't add up.
249
00:11:41,134 --> 00:11:44,302
Nelson: In a group this size,
if you found food,
250
00:11:44,304 --> 00:11:46,838
You might not want the
entire group to know
251
00:11:46,840 --> 00:11:48,239
Where it was.
252
00:11:48,241 --> 00:11:50,442
I mean, we're talking thousands
and thousands of birds
253
00:11:50,444 --> 00:11:53,611
Because then
you'd be out of food.
254
00:11:53,613 --> 00:11:55,980
Narrator:
Communication is ruled out,
255
00:11:55,982 --> 00:11:59,217
So what is the reason
starlings murmurate?
256
00:11:59,219 --> 00:12:01,219
Daly: When we analyze
a starling murmuration
257
00:12:01,221 --> 00:12:05,090
There's often one thing
that's fairly evident,
258
00:12:05,092 --> 00:12:07,759
That's the presence
of a predator.
259
00:12:19,172 --> 00:12:21,606
Narrator: For years, scientists
have been trying to get
260
00:12:21,608 --> 00:12:25,477
To the bottom of why
starlings murmurate.
261
00:12:25,479 --> 00:12:29,047
They then noticed the
gatherings of these starlings
262
00:12:29,049 --> 00:12:33,351
Often had one thing in common --
a bird of prey.
263
00:12:33,353 --> 00:12:38,356
So are the starlings
murmurating to avoid predators.
264
00:12:38,358 --> 00:12:41,192
Narrator: To find out,
we visited anne goodenough,
265
00:12:41,194 --> 00:12:44,229
A biologist who's been
studying starlings for years.
266
00:12:44,231 --> 00:12:47,966
To ask her if predators
could be the cause.
267
00:12:47,968 --> 00:12:50,301
There's a link between
size of the murmuration
268
00:12:50,303 --> 00:12:55,406
And the number of predators
present and their activity.
269
00:12:55,408 --> 00:12:59,778
We found that when you got
predators that were flying in
270
00:12:59,780 --> 00:13:03,615
And around the flock you tended
to get bigger murmurations
271
00:13:03,617 --> 00:13:10,121
And the birds stayed
up a lot longer.
272
00:13:10,123 --> 00:13:12,157
Narrator: Anne thinks
murmurations are likely to be
273
00:13:12,159 --> 00:13:15,260
A strategy that starlings
use against predators
274
00:13:15,262 --> 00:13:18,963
Like falcons, eagles,
and hawks.
275
00:13:23,336 --> 00:13:27,639
Goodenough: So when a predator
flies into a starling flock,
276
00:13:27,641 --> 00:13:30,608
It will try and get focus lock
on one specific individual
277
00:13:30,610 --> 00:13:33,978
And go in after that
one specific individual,
278
00:13:33,980 --> 00:13:39,117
Exactly in the way that
a targeted missile would work.
279
00:13:39,119 --> 00:13:43,521
If that individual is part
of a swirling 3d mass,
280
00:13:43,523 --> 00:13:47,492
It's much more difficult to
get and maintain focus lock
281
00:13:47,494 --> 00:13:51,429
And ultimately
hunt successfully.
282
00:13:51,431 --> 00:13:54,098
Narrator: Footage of a predator
attacking the murmuration
283
00:13:54,100 --> 00:13:59,137
Show this defensive
technique in action.
284
00:13:59,139 --> 00:14:03,541
Goodenough: That looks like
a peregrine falcon,
285
00:14:03,543 --> 00:14:07,312
And you can see that as it's
diving in and through the flock
286
00:14:07,314 --> 00:14:10,215
The birds are reacting
to it's presence.
287
00:14:10,217 --> 00:14:12,350
The birds are repelling
away from that,
288
00:14:12,352 --> 00:14:14,686
Just like iron fillings
when they're exposed
289
00:14:14,688 --> 00:14:17,922
To the wrong end of a magnet.
290
00:14:17,924 --> 00:14:20,491
And this is one of
those key ideas for why
291
00:14:20,493 --> 00:14:24,929
Murmurations occur
in the first place.
292
00:14:24,931 --> 00:14:29,133
And actually this falcon
isn't doing terribly well,
293
00:14:29,135 --> 00:14:30,902
It's flying in and
through the flock,
294
00:14:30,904 --> 00:14:32,470
But it's actually
not being successful
295
00:14:32,472 --> 00:14:38,009
In catching it's dinner.
296
00:14:38,011 --> 00:14:39,077
Aryee: For these starlings
are gathering
297
00:14:39,079 --> 00:14:40,678
In these huge murmurations,
298
00:14:40,680 --> 00:14:43,581
They are trying to
deliberately confuse
299
00:14:43,583 --> 00:14:46,751
A potential predator
and this is called
300
00:14:46,753 --> 00:14:48,853
Predator confusion theory.
301
00:14:48,855 --> 00:14:50,421
Narrator:
But during murmurations,
302
00:14:50,423 --> 00:14:52,857
It's not just predator
confusion that's at play,
303
00:14:52,859 --> 00:14:55,059
The sheer numbers involved in it
304
00:14:55,061 --> 00:14:56,628
Means the starlings
are also employing
305
00:14:56,630 --> 00:15:00,331
What scientists call,
the dilution effect.
306
00:15:00,333 --> 00:15:03,701
The dilution effect, essentially
is safety in numbers.
307
00:15:03,703 --> 00:15:05,370
Nelson: It's simple math.
308
00:15:05,372 --> 00:15:07,305
If you're one lone individual,
309
00:15:07,307 --> 00:15:10,475
And you see a predator,
you're chances are pretty high
310
00:15:10,477 --> 00:15:12,677
That you're gonna
get chomped.
311
00:15:12,679 --> 00:15:14,946
But if there's a thousand
more of ya out there,
312
00:15:14,948 --> 00:15:17,916
You decrease your
chances by a thousand.
313
00:15:17,918 --> 00:15:20,151
Narrator:
So for starlings, a murmuration
314
00:15:20,153 --> 00:15:22,921
Isn't just a dance in the sky,
315
00:15:22,923 --> 00:15:25,723
It's an effective
aid in survival.
316
00:15:25,725 --> 00:15:32,230
♪
317
00:15:32,232 --> 00:15:37,635
August 7, 2015,
hwange national park, zimbabwe.
318
00:15:37,637 --> 00:15:40,305
A tourist is recording
his safari adventure,
319
00:15:40,307 --> 00:15:43,775
When his tracker spots
a hunt in progress.
320
00:15:43,777 --> 00:15:46,077
And the hunter
isn't just any predator,
321
00:15:46,079 --> 00:15:49,881
It's the cheetah, the fastest
land animal on the planet.
322
00:15:49,883 --> 00:15:54,953
♪
323
00:15:54,955 --> 00:15:57,689
This cat goes from
zero to 60 miles and hour
324
00:15:57,691 --> 00:16:02,126
In just three seconds.
325
00:16:02,128 --> 00:16:05,563
Burke: Everything about these
animals are built for speed,
326
00:16:05,565 --> 00:16:07,332
They have this
lightweight skeleton,
327
00:16:07,334 --> 00:16:08,533
Really long legs,
328
00:16:08,535 --> 00:16:11,903
Which allows them to
take these huge strides.
329
00:16:11,905 --> 00:16:14,372
They even have a
specialized inner ear canal,
330
00:16:14,374 --> 00:16:16,874
Which helps to keep their
head completely fixed
331
00:16:16,876 --> 00:16:18,376
On their prey.
332
00:16:18,378 --> 00:16:22,814
And then a really long tail
which acts like a rudder.
333
00:16:22,816 --> 00:16:24,582
Galante: Cheetah have
incredible flexibility
334
00:16:24,584 --> 00:16:27,885
That allow them to pivot on
a dime and they can withstand
335
00:16:27,887 --> 00:16:31,723
G forces that would
break a human beings leg.
336
00:16:31,725 --> 00:16:37,662
Narrator: Their prey doesn't
stand a chance.
337
00:16:37,664 --> 00:16:41,833
But hang on a second,
the cheetah's given up.
338
00:16:41,835 --> 00:16:43,935
Why?
339
00:16:43,937 --> 00:16:46,004
Cheetahs often
throw in the towel
340
00:16:46,006 --> 00:16:49,674
Even when it seems
their prey is in range.
341
00:16:49,676 --> 00:16:51,809
Burke: So with all these
incredible adaptations
342
00:16:51,811 --> 00:16:54,445
Begs the question,
why are only 58%
343
00:16:54,447 --> 00:16:56,547
Of their hunts successful.
344
00:16:56,549 --> 00:16:58,716
How is that possible?
345
00:17:09,062 --> 00:17:11,529
Narrator:
Footage shows that the cheetah,
346
00:17:11,531 --> 00:17:15,733
The world's fastest land
animal, giving up the chase.
347
00:17:15,735 --> 00:17:19,871
Again and again
348
00:17:19,873 --> 00:17:23,041
And again.
349
00:17:23,043 --> 00:17:26,411
Why do they give up so often?
350
00:17:26,413 --> 00:17:29,714
Burke:
Are they easily distracted?
351
00:17:29,716 --> 00:17:31,749
Narrator: Mother cheetahs
usually have three
352
00:17:31,751 --> 00:17:35,353
Or four major distractions,
their cubs.
353
00:17:35,355 --> 00:17:38,222
Cheetah cubs are at great risk
from lions, leopards,
354
00:17:38,224 --> 00:17:40,124
And hyenas, especially
when their mothers
355
00:17:40,126 --> 00:17:41,926
Leave them to hunt.
356
00:17:41,928 --> 00:17:44,128
Galante: A mother cheetah is
particularly stressed,
357
00:17:44,130 --> 00:17:47,532
Because only 40% of cubs
make it to adulthood
358
00:17:47,534 --> 00:17:51,502
In the kalahari and 5%
percent in the sahara.
359
00:17:51,504 --> 00:17:53,337
Daly: So all cheetahs
abandoning the hunt
360
00:17:53,339 --> 00:17:55,206
Because of having to be alert
361
00:17:55,208 --> 00:17:57,041
And be on the look-out
for predators
362
00:17:57,043 --> 00:18:00,311
In order for them to
keep their cubs safe?
363
00:18:00,313 --> 00:18:02,914
Narrator: There is one problem
with this idea,
364
00:18:02,916 --> 00:18:05,316
Male cheetahs also
give up the chase
365
00:18:05,318 --> 00:18:10,521
And they don't play
a role in caring for cubs.
366
00:18:10,523 --> 00:18:12,924
So could it instead
be physical stress,
367
00:18:12,926 --> 00:18:17,862
That causes the
cheetahs to burn out.
368
00:18:17,864 --> 00:18:19,864
In an effort
to avoid competition
369
00:18:19,866 --> 00:18:21,265
From other predators,
370
00:18:21,267 --> 00:18:23,101
Cheetahs hunt
during the daytime
371
00:18:23,103 --> 00:18:26,137
When other big cats
are sleeping.
372
00:18:26,139 --> 00:18:29,640
However, this can make
hunting even more exhausting.
373
00:18:29,642 --> 00:18:31,375
Burke: One of the downsides
of hunting in the middle
374
00:18:31,377 --> 00:18:35,113
Of the day is that it's also
the hottest part of the day.
375
00:18:35,115 --> 00:18:36,747
Once they decide to give chase,
376
00:18:36,749 --> 00:18:38,649
They only have
a limited amount of time
377
00:18:38,651 --> 00:18:42,954
Before their bodies
start to overheat.
378
00:18:42,956 --> 00:18:44,655
Narrator:
In polokwane, south africa
379
00:18:44,657 --> 00:18:49,093
Dr. Robyn hetem, who studies
cheetahs living in sanctuaries,
380
00:18:49,095 --> 00:18:51,295
Put the overheating
theory to the test
381
00:18:51,297 --> 00:18:54,632
Using the latest
heat monitoring technology.
382
00:18:54,634 --> 00:18:57,602
Hetem: We were able to attach
small biologging devices
383
00:18:57,604 --> 00:19:00,304
Which could remotely
assess body temperature
384
00:19:00,306 --> 00:19:04,442
Off free-living cheetah
in real hunting experiences.
385
00:19:04,444 --> 00:19:13,718
♪
386
00:19:13,720 --> 00:19:15,653
Narrator:
So what did she discover?
387
00:19:15,655 --> 00:19:18,122
Hetem: Surprisingly we found
no temperature increase
388
00:19:18,124 --> 00:19:19,557
When cheetah were hunting.
389
00:19:19,559 --> 00:19:22,293
The cat is able to dissipate
that heat effectively
390
00:19:22,295 --> 00:19:24,495
Through evaporative cooling.
391
00:19:24,497 --> 00:19:26,697
Narrator:
Overheating is ruled out,
392
00:19:26,699 --> 00:19:32,270
So what is causing cheetahs
to give up the chase?
393
00:19:32,272 --> 00:19:35,673
Professor alan wilson from
the royal veterinary college
394
00:19:35,675 --> 00:19:39,410
In the uk analyzes the footage,
395
00:19:39,412 --> 00:19:41,612
He reveals that its he
direction of the chase
396
00:19:41,614 --> 00:19:45,716
That can foil cheetahs.
397
00:19:45,718 --> 00:19:47,919
Hunts don't happen
in a straight line,
398
00:19:47,921 --> 00:19:50,521
It involves turning, it
involves ducking and diving
399
00:19:50,523 --> 00:19:53,491
As the antelope tries to
escape and the cheetah tries
400
00:19:53,493 --> 00:19:59,096
To follow those movements.
401
00:19:59,098 --> 00:20:02,600
Very rarely do cheetahs even
approach half their top speed
402
00:20:02,602 --> 00:20:05,536
Hunting, it's not
about absolute speed,
403
00:20:05,538 --> 00:20:09,373
It's about maneuverability.
404
00:20:09,375 --> 00:20:10,908
Narrator:
And it's the zig-zagging course
405
00:20:10,910 --> 00:20:13,611
That prey, such as antelope,
go on
406
00:20:13,613 --> 00:20:17,381
That sometimes gives
them the upper hand.
407
00:20:17,383 --> 00:20:19,283
Wilson: This is because the
antelope defines the hunt
408
00:20:19,285 --> 00:20:21,652
By setting course
that is challenging
409
00:20:21,654 --> 00:20:23,187
For the cheetah to follow.
410
00:20:23,189 --> 00:20:27,291
And that is where the
antelope gains it's advantage.
411
00:20:27,293 --> 00:20:29,994
Narrator: Meaning cheetahs
don't just need speed,
412
00:20:29,996 --> 00:20:33,164
They need agility to get a meal.
413
00:20:33,166 --> 00:20:36,133
When a cheetah is hunting prey,
it's the first one
414
00:20:36,135 --> 00:20:37,935
To make a mistake that loses.
415
00:20:37,937 --> 00:20:40,738
The cheetah makes a mistake,
the prey is going to win.
416
00:20:40,740 --> 00:20:45,109
Narrator:
So, while cheetahs remain
the fastest land animals
417
00:20:45,111 --> 00:20:49,347
On the planet, sometimes even
they have to admit defeat.
418
00:20:49,349 --> 00:20:52,350
-- Captions by vitac --
www.Vitac.Com
419
00:20:52,352 --> 00:20:55,419
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