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Narrator: Ever wonder
what could swallow
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50-foot trees in seconds?
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That's huge.
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Narrator: What mystery creature
could transform
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An entire landscape?
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It's just --
it changes everything.
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Narrator: And what's the point
of the world's weirdest tusk?
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This is the first time
this behavior
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Is ever been caught on camera.
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Narrator:
Nature is awe-inspiring.
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But sometimes it just
doesn't make sense.
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Man: I have never seen
anything like this.
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Our team of experts investigate
the weirdest animal behavior...
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That's amazing.
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...And the most unexpected
events...
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What is causing that?
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...Ever caught on camera.
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My god!
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Narrator: These are...
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♪
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June 2016 --
a team of scientists
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And wildlife filmmakers
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Are on an expedition
to study narwhals.
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Their mission --
to try and solve
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One of the greatest mysteries
of the natural world.
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So, the big question is,
why on earth
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Have they evolved
this extraordinary structure?
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Narrator:
On a routine drone flight,
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They capture narwhals
doing something very strange
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With their most distinctive
feature -- their tusk.
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It wasn't till we got
the drone back
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That we looked at the footage
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And we realized
we had something special.
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♪
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Narrator: Narwhals usually glide
smoothly through the water,
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But look closely,
and these ones are not.
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They seem to be
shaking their heads.
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Narwhals have never been
filmed doing this before.
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♪
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Could this activity help us
crack the age-old mystery
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Of what their tusks are for?
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It's got to be there
for something, but what?
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Narrator: Well, historically,
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It's been thought that narwhals
use their tusks as ice picks.
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♪
46
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So, narwhals are whales,
they're mammals,
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They breathe air,
and they live in the arctic,
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So it's very possible that they
could get trapped under ice.
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Could that extremely long tusk
be used to find holes in the ice
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Through which they can breathe?
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Narrator: Finding air holes
in the pack ice
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Is a common problem for
arctic mammals.
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Seals, for example,
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Play russian roulette
with polar bears
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When coming up to breathe.
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♪
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They've never been seen,
actually,
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Doing this sort of behavior.
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The narwhal uses the back
of its melon
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To actually break ice
that's thicker.
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The last thing that this whale
wants to do is endanger its tusk
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Because if it breaks, it's not
going to repair very well.
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And so, it seems unlikely
that this is, at least,
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The primary purpose
for the tusk.
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So, they're not ice picks,
but they are very strong.
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Another theory is
if it looks like a sword
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And it moves like a sword,
maybe it's a sword, right?
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Maybe the males are using
these tusks
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To have sword fights
to try to win females.
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Is this footage
of a narwhal showdown?
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Could these tusks be used to
face down competitors?
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♪
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Cooke: Is it like
the antlers of a deer
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And used by males
in dominance battles?
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[ grunts ]
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♪
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[ grunts ]
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♪
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Narrator:
Could be, but look closely
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And there doesn't seem to be
any direct contact,
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And previous
arctic narwhal expeditions
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Have reported that narwhals
are a gentle species.
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When you look at footage
of these tusks
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Touching each other,
it's very gentle,
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So it really doesn't seem like
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They're fighting with them
at all.
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Narrator: It seems narwhals
are naturally gentle,
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But this might still be
a display of dominance.
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Is the tusk there
to attract females?
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Sometimes, just looking gorgeous
is enough.
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All male narwhals have tusks,
so that would suggest
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That it could be something
that's evolved
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As part of sexual selection
and dominance behavior.
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♪
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Riskin: Maybe females think
those tusks
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Are just darned sexy,
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And so the longer the tusk,
the more attractive the male is.
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That would certainly be
sufficient to make them evolve.
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Narrator: So, is this
a male narwhal beauty pageant?
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Well, it could be, except...
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Females, in about 15% of cases,
also have a tusk.
102
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Narrator:
...Some ladies have them, too.
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Nice gigantic spikes, girls.
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If you look closely,
you can also just make out
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Some baby narwhals
with their moms.
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Narwhals give birth in July,
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And that means
it's too late for mating.
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There's something else going on,
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And it could relate to what
the tusks are made of.
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♪
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Turns out, the narwhal tusk
is a tooth.
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It's actually
an elongated canine tooth
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That just sticks out
of the mouth.
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I mean, if you look carefully,
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It doesn't come out
of the middle,
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It comes out of the side.
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It's just a really weird tooth.
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That tooth can get 9 feet long.
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Narrator: And the perfect person
to study a tooth?
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A dentist, of course.
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I would basically be a marine
mammal tooth specialist,
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Or odontologist, if you would.
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Narrator: We'll stick with
tooth specialist.
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Narwhals are born
with only two teeth,
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And usually one stays
completely hidden in their jaw.
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So this single extended
lopsided tusk
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Is their most prized possession.
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So apart from being
the only straight,
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Spiraled 9-foot tooth
in the animal kingdom,
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What else makes it so special?
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♪
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Nweeia: Hard to believe,
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But along the surface
of this tusk, or tooth,
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Are millions of little tubes
that connects the inner nerve --
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Which runs the full length
of this, by the way --
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To the outside environment.
137
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And just like people have
sensitivity in their teeth
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To hot, to cold,
to certain flavors like sugar,
139
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This long tooth
is basically sensitive
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To these sorts of things,
as well.
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It can basically taste
the water.
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If you can believe it,
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This tooth can measure
how salty the water is.
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Narrator: So, is the narwhal
tusk a giant antenna,
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A secret weapon
for sensing its surroundings?
146
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And if so,
could that hold the answer
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00:07:18,338 --> 00:07:21,873
To what's happening
in the footage?
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Scientists have been
arguing over
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What the tusk does
for centuries,
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But martin thinks that as well
as detecting salinity,
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It can gauge other things,
like temperature, pressure,
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And concentrations
of different particles.
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Because we think this tusk
has other attributes,
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It may play
into the role of hunting
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By detecting
certain gradients of water
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Where fish that
the whale wants are.
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Narrator: And once they've
found fish with their tusks,
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These amazing sense organs could
be repurposed to attack them.
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Is that what they're doing
in the drone footage?
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If you look very carefully,
they're whacking fish with them.
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♪
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Ravetch: The narwhal are clearly
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Knocking those fish
over their heads.
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They're clubbing them,
and it's repeated hits,
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And then they slurp it up.
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We have feeding,
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We have something that
no one's ever captured before.
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It was the holy grail.
169
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Narrator: But like all good
scientific mysteries,
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The debate is still raging.
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The video footage shows
some of the fish
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Being tapped by the tusk
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And implying that
they're stunned by the tusk,
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When in fact, the tusk may be
just the way of it
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Knocking the food into
their mouth.
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The food may likely
have already been stunned.
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Narrator: Whether
multipurpose narwhal tusks
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Are for clubbing fish or for
guiding them to their mouths,
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This footage of narwhals using
their tusks to feed
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Is a world first,
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And it's helped crack
a centuries-old mystery --
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What is the purpose
of the most unique,
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Incredible tooth in the whole
of the animal kingdom?
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♪
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The northern range --
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Yellowstone national park,
u.S.A.
187
00:09:22,296 --> 00:09:26,064
Satellite images reveal
a rapidly changing landscape.
188
00:09:26,066 --> 00:09:29,935
Lakes are forming and rivers
are shifting course.
189
00:09:29,937 --> 00:09:31,937
Down on the ground,
trees are growing
190
00:09:31,939 --> 00:09:33,638
Where they haven't for years,
191
00:09:33,640 --> 00:09:37,375
And something else weird
has happened.
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00:09:37,377 --> 00:09:40,812
For six decades,
this has been elk paradise.
193
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In the mid '90s,
elk populations were booming.
194
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Narrator: Back then, there were
over 19,000 elk here,
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00:09:47,821 --> 00:09:51,222
But today,
only around 6,000 remain.
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They've been spooked.
197
00:09:52,893 --> 00:09:57,062
The question is, what's happened
to yellowstone's elk?
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00:09:57,064 --> 00:10:00,131
♪
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♪
200
00:10:09,109 --> 00:10:11,042
Narrator:
In yellowstone national park,
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The landscape has been
transforming,
202
00:10:13,547 --> 00:10:17,082
And elk numbers have shrunk
by nearly 70%.
203
00:10:17,084 --> 00:10:19,551
They've started behaving
very oddly.
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00:10:19,553 --> 00:10:22,354
Instead of hanging out
in giant groups
205
00:10:22,356 --> 00:10:23,822
In the middle of the fields,
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00:10:23,824 --> 00:10:26,725
They started moving into
small groups in the woods.
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00:10:26,727 --> 00:10:28,059
So the question is,
208
00:10:28,061 --> 00:10:31,563
What is changing
yellowstone national park?
209
00:10:31,565 --> 00:10:33,231
Narrator:
What has changed in yellowstone
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00:10:33,233 --> 00:10:35,200
Over the past 20 years
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00:10:35,202 --> 00:10:38,236
To cause the elk
to move to new pastures?
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00:10:38,238 --> 00:10:41,539
♪
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00:10:41,541 --> 00:10:45,443
Elk are one of the resident
grazers in the national park.
214
00:10:45,445 --> 00:10:48,680
They eat willows, berry bushes,
aspen cottonwood --
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00:10:48,682 --> 00:10:50,382
A variety of plants.
216
00:10:50,384 --> 00:10:53,051
Narrator: All of these plants
grow in the river valleys,
217
00:10:53,053 --> 00:10:56,454
Which used to be
prime real estate for elk.
218
00:10:56,456 --> 00:10:59,257
But now, there's another
furry critter
219
00:10:59,259 --> 00:11:01,426
Taking over the waterways,
220
00:11:01,428 --> 00:11:04,896
And they've seen a surge
in population.
221
00:11:04,898 --> 00:11:07,399
Are they what made the elk move?
222
00:11:10,370 --> 00:11:14,973
Are beavers what's changed
yellowstone national park?
223
00:11:14,975 --> 00:11:16,274
Baker: Since the mid '90s,
224
00:11:16,276 --> 00:11:19,711
As the elk numbers
have been going down,
225
00:11:19,713 --> 00:11:22,080
The beaver numbers have been
going up.
226
00:11:22,082 --> 00:11:25,316
Narrator: Beaver business
has been booming in yellowstone,
227
00:11:25,318 --> 00:11:27,986
And they've been going to town
on their favorite food --
228
00:11:27,988 --> 00:11:32,123
Willow, which is also
the elks preferred dinner.
229
00:11:32,125 --> 00:11:36,127
So, have they starved the elk
out of the area?
230
00:11:36,129 --> 00:11:40,131
Well, beavers are effectively
hydro engineers.
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00:11:40,133 --> 00:11:43,835
♪
232
00:11:43,837 --> 00:11:45,203
They will build dams,
233
00:11:45,205 --> 00:11:47,639
They will cut down trees
that line the rivers,
234
00:11:47,641 --> 00:11:50,275
And they will change the entire
ecology of a river system
235
00:11:50,277 --> 00:11:51,576
Based on their needs.
236
00:11:51,578 --> 00:11:56,381
♪
237
00:11:56,383 --> 00:12:00,652
Narrator: Since the mid '90s,
beaver numbers have grown,
238
00:12:00,654 --> 00:12:03,021
But contrary
to what you might expect,
239
00:12:03,023 --> 00:12:06,658
So have the willow trees.
240
00:12:06,660 --> 00:12:09,794
These beavers pay back more
than they take.
241
00:12:09,796 --> 00:12:13,431
Creating a dam actually creates
habitat for more willows.
242
00:12:13,433 --> 00:12:16,968
♪
243
00:12:16,970 --> 00:12:18,870
Beaver dams
raise the water level,
244
00:12:18,872 --> 00:12:20,205
Which create mud flats.
245
00:12:20,207 --> 00:12:21,840
Mud flats are
the perfect environment
246
00:12:21,842 --> 00:12:23,575
For willow trees to grow.
247
00:12:23,577 --> 00:12:25,076
So, it's kind of this
weird process
248
00:12:25,078 --> 00:12:27,479
Where even though the beavers
are eating willows,
249
00:12:27,481 --> 00:12:30,215
They're creating habitat
for more willows.
250
00:12:30,217 --> 00:12:33,118
Galante: The very same food that
the beavers need to eat
251
00:12:33,120 --> 00:12:34,586
And use as building materials.
252
00:12:34,588 --> 00:12:35,987
It's a perfect cycle.
253
00:12:35,989 --> 00:12:39,624
♪
254
00:12:39,626 --> 00:12:41,059
Narrator: The beavers
have actually increased
255
00:12:41,061 --> 00:12:44,896
The amount of food available
for the elk.
256
00:12:44,898 --> 00:12:48,333
So why did the elk leave?
257
00:12:48,335 --> 00:12:51,836
Both the beavers and the elk
are intrinsically connected,
258
00:12:51,838 --> 00:12:54,038
Linked to the changes
in the landscape
259
00:12:54,040 --> 00:12:57,809
And also to a predator
even higher up the food chain.
260
00:12:57,811 --> 00:13:01,679
♪
261
00:13:01,681 --> 00:13:05,750
The answer to this has to do
with an experiment
262
00:13:05,752 --> 00:13:07,118
That was run in the 1990s,
263
00:13:07,120 --> 00:13:11,289
Where biologists brought
an animal back to yellowstone
264
00:13:11,291 --> 00:13:13,324
That had previously
been killed out.
265
00:13:13,326 --> 00:13:16,661
[ howling ]
266
00:13:22,936 --> 00:13:26,805
♪
267
00:13:26,807 --> 00:13:28,506
Narrator:
In yellowstone national park,
268
00:13:28,508 --> 00:13:30,809
The entire landscape, rivers,
269
00:13:30,811 --> 00:13:33,378
And trees
have been transforming,
270
00:13:33,380 --> 00:13:36,114
And it's down to
a very unlikely culprit.
271
00:13:38,952 --> 00:13:43,421
To understand what happened,
we need to rewind by a century.
272
00:13:43,423 --> 00:13:46,090
♪
273
00:13:46,092 --> 00:13:47,425
[ howling ]
smith: Wolves were begun
274
00:13:47,427 --> 00:13:51,596
To be eradicated in 1872,
when the park was established,
275
00:13:51,598 --> 00:13:55,934
And the last wolf was killed
in 1926.
276
00:13:55,936 --> 00:13:58,636
Riskin: People tend
to hate wolves.
277
00:13:58,638 --> 00:14:00,438
They've always had a bad rap,
278
00:14:00,440 --> 00:14:03,241
And this ultimately spelled
the demise
279
00:14:03,243 --> 00:14:06,077
For the whole species
in yellowstone, originally.
280
00:14:09,049 --> 00:14:13,418
They're a carnivore, so that
means they kill for a living,
281
00:14:13,420 --> 00:14:17,021
But most everything kills for
a living in some way or another.
282
00:14:17,023 --> 00:14:20,458
So singling the wolves out
as the demon
283
00:14:20,460 --> 00:14:22,193
Has been unfair through time.
284
00:14:22,195 --> 00:14:24,562
♪
285
00:14:24,564 --> 00:14:25,997
Narrator:
No wolves in yellowstone
286
00:14:25,999 --> 00:14:28,266
Meant an elk explosion.
287
00:14:28,268 --> 00:14:31,936
♪
288
00:14:31,938 --> 00:14:37,175
Their numbers shot up
to over 19,000 individuals.
289
00:14:37,177 --> 00:14:40,345
All those hungry mouths
overgrazed the land
290
00:14:40,347 --> 00:14:43,414
And stopped the trees
from growing.
291
00:14:43,416 --> 00:14:46,084
That meant no berries
for the bears
292
00:14:46,086 --> 00:14:48,453
And no habitat for the birds.
293
00:14:48,455 --> 00:14:50,955
The ecosystem became sick
and animals
294
00:14:50,957 --> 00:14:52,156
Moved out of yellowstone.
295
00:14:52,158 --> 00:14:56,794
In 1995 is when everything
started to change.
296
00:14:56,796 --> 00:14:59,197
Officials decided
to reintroduce wolves
297
00:14:59,199 --> 00:15:00,798
Into yellowstone national park.
298
00:15:00,800 --> 00:15:02,600
[ howls ]
299
00:15:02,602 --> 00:15:04,969
Bringing the wolves back
to yellowstone
300
00:15:04,971 --> 00:15:08,840
Was as an emotional moment
as you'll get.
301
00:15:08,842 --> 00:15:10,708
I mean, when they came through
the arch,
302
00:15:10,710 --> 00:15:12,844
Which is the entrance
to yellowstone,
303
00:15:12,846 --> 00:15:15,380
It was almost like
crossing the threshold.
304
00:15:15,382 --> 00:15:17,982
Narrator:
Back in their natural habitat,
305
00:15:17,984 --> 00:15:21,052
The wolves settled in and bred.
306
00:15:22,455 --> 00:15:24,622
The results were dramatic.
307
00:15:24,624 --> 00:15:27,058
♪
308
00:15:27,060 --> 00:15:29,794
Smith: We reintroduced
a total of 41 wolves,
309
00:15:29,796 --> 00:15:33,798
And now we have about
100 wolves in 10 packs.
310
00:15:33,800 --> 00:15:37,168
Wolves change everything
because they're apex predators.
311
00:15:37,170 --> 00:15:40,305
They're the keystone species
in this whole thing.
312
00:15:40,307 --> 00:15:44,008
Narrator: First in the wolves'
sights were the elk.
313
00:15:44,010 --> 00:15:47,412
So, you put wolves in --
wolves like elk an awful lot,
314
00:15:47,414 --> 00:15:49,414
Elk don't like wolves very much.
315
00:15:49,416 --> 00:15:51,416
Nelson: Elk love willows,
so most of their time
316
00:15:51,418 --> 00:15:54,752
Was spent down in the lowland
areas where these willows lived.
317
00:15:54,754 --> 00:15:56,621
Baker: Wolves go to
where the elk are hanging out,
318
00:15:56,623 --> 00:15:59,924
And immediately,
without even catching an elk,
319
00:15:59,926 --> 00:16:01,759
The elk have moved.
320
00:16:01,761 --> 00:16:03,695
They stirred them up.
321
00:16:03,697 --> 00:16:06,564
So now, all of a sudden,
the elk are in smaller groups.
322
00:16:06,566 --> 00:16:08,299
They're hiding in the woods.
323
00:16:08,301 --> 00:16:10,401
That means that all these plants
are growing up
324
00:16:10,403 --> 00:16:12,070
That couldn't grow before.
325
00:16:12,072 --> 00:16:13,972
♪
326
00:16:13,974 --> 00:16:17,308
Narrator: More willows
meant beavers could return.
327
00:16:17,310 --> 00:16:20,745
More fish, more things
that eat fish.
328
00:16:20,747 --> 00:16:23,848
Birds are back because they've
got somewhere to breed.
329
00:16:23,850 --> 00:16:26,484
The bears have got berries
to feed on.
330
00:16:26,486 --> 00:16:29,821
They never would have predicted
the positive outcomes
331
00:16:29,823 --> 00:16:31,589
Of just putting
these apex predators
332
00:16:31,591 --> 00:16:33,624
Back where they belonged.
333
00:16:36,363 --> 00:16:39,697
Narrator: The wolves that were
once seen as the demons
334
00:16:39,699 --> 00:16:42,533
Have rebalanced
the entire ecosystem.
335
00:16:42,535 --> 00:16:47,638
♪
336
00:16:47,640 --> 00:16:52,710
♪
337
00:16:52,712 --> 00:16:54,812
August 2013 --
338
00:16:54,814 --> 00:16:57,782
Assumption parish, louisiana.
339
00:16:57,784 --> 00:17:00,284
On a normally placid lake,
340
00:17:00,286 --> 00:17:03,921
The water begins to move
towards the center.
341
00:17:03,923 --> 00:17:08,526
The trees begin to sink
faster and faster,
342
00:17:08,528 --> 00:17:11,696
Until all 50 feet of them are
completely swallowed.
343
00:17:11,698 --> 00:17:14,699
♪
344
00:17:14,701 --> 00:17:17,468
What is going on?
345
00:17:17,470 --> 00:17:19,937
♪
346
00:17:26,146 --> 00:17:29,180
♪
347
00:17:29,182 --> 00:17:31,115
Narrator: In assumption parish,
louisiana,
348
00:17:31,117 --> 00:17:33,084
50-foot trees are swallowed
349
00:17:33,086 --> 00:17:36,521
Into the belly
of apparently placid water.
350
00:17:36,523 --> 00:17:39,290
So how is it possible
that this area in louisiana
351
00:17:39,292 --> 00:17:41,659
Has trees that within seconds
352
00:17:41,661 --> 00:17:45,663
Just completely sucked
under water
353
00:17:45,665 --> 00:17:47,432
Into this lake.
354
00:17:47,434 --> 00:17:49,867
Narrator:
This area is marshy swampland.
355
00:17:49,869 --> 00:17:53,337
The water is way too shallow
to absorb these trees.
356
00:17:53,339 --> 00:17:55,506
So what's happening beneath
the surface
357
00:17:55,508 --> 00:17:59,410
That could consume them
from the roots up?
358
00:17:59,412 --> 00:18:00,845
The first thing that
comes to mind
359
00:18:00,847 --> 00:18:03,514
Is probably some sort of
sinkhole opening up...
360
00:18:04,984 --> 00:18:07,018
...And swallowing these trees.
361
00:18:07,020 --> 00:18:14,792
♪
362
00:18:14,794 --> 00:18:22,600
♪
363
00:18:22,602 --> 00:18:25,269
So all across the u.S.,
364
00:18:25,271 --> 00:18:27,071
There are these things
called sinkholes...
365
00:18:29,976 --> 00:18:33,177
...Where all of a sudden,
the ground just falls down,
366
00:18:33,179 --> 00:18:35,613
Revealing a cave
that nobody knew was there,
367
00:18:35,615 --> 00:18:38,282
And this could be
what's happening in louisiana.
368
00:18:38,284 --> 00:18:40,685
These cavities in the rock
can be massive.
369
00:18:40,687 --> 00:18:43,855
I mean, we're talking about
hundreds of meters across,
370
00:18:43,857 --> 00:18:45,523
Hundreds of meters deep.
371
00:18:45,525 --> 00:18:48,426
Sinkholes form in various ways,
372
00:18:48,428 --> 00:18:50,061
One of which is that
you have a source of water
373
00:18:50,063 --> 00:18:51,395
Running underneath the ground
374
00:18:51,397 --> 00:18:54,332
And it's eroding the soil,
the bedrock,
375
00:18:54,334 --> 00:18:57,001
Leaving an open space,
leaving a vacuum.
376
00:18:57,003 --> 00:18:59,036
Nelson:
The cavity forms underground,
377
00:18:59,038 --> 00:19:01,739
And then the roof gets
destabilized
378
00:19:01,741 --> 00:19:05,143
And the roof of the cavity
collapses, causing a sinkhole.
379
00:19:07,380 --> 00:19:08,746
Narrator:
Generally, it's limestone
380
00:19:08,748 --> 00:19:12,783
Or other carbonate rocks
that give way to sinkholes,
381
00:19:12,785 --> 00:19:16,621
But there's something about
this area that doesn't add up.
382
00:19:16,623 --> 00:19:18,322
The problem with the idea
of a sinkhole
383
00:19:18,324 --> 00:19:21,092
Is that this area
doesn't have limestone.
384
00:19:23,696 --> 00:19:25,930
The bedrock is not limestone.
385
00:19:25,932 --> 00:19:28,833
We're in a bayou in louisiana.
386
00:19:28,835 --> 00:19:31,102
So this is something else
387
00:19:31,104 --> 00:19:33,304
That's causing those trees
to go down.
388
00:19:33,306 --> 00:19:36,140
Narrator: This area might not
be known for limestone,
389
00:19:36,142 --> 00:19:38,776
But it is known
for a different mineral,
390
00:19:38,778 --> 00:19:40,511
One that you wouldn't expect
to be hiding under
391
00:19:40,513 --> 00:19:44,015
Miles of swampy,
wet mississippi bayou.
392
00:19:45,618 --> 00:19:46,851
Salt.
393
00:19:46,853 --> 00:19:51,856
♪
394
00:19:51,858 --> 00:19:55,226
And that could be the key to
the disappearing trees.
395
00:19:55,228 --> 00:20:05,236
♪
396
00:20:05,238 --> 00:20:07,371
150 million years ago,
397
00:20:07,373 --> 00:20:10,341
Huge natural salt deposits
formed in this area
398
00:20:10,343 --> 00:20:13,444
When an ancient salty ocean
evaporated,
399
00:20:13,446 --> 00:20:17,982
And we've been extracting
that salt for over 150 years.
400
00:20:17,984 --> 00:20:21,352
The way you mine for salt
is to find a deposit
401
00:20:21,354 --> 00:20:23,754
Where there is
really salty soil,
402
00:20:23,756 --> 00:20:27,191
You spray it with water, turning
it into this briny liquid,
403
00:20:27,193 --> 00:20:29,093
And then you suck it up a straw.
404
00:20:29,095 --> 00:20:31,629
When you do that,
you leave a cave behind.
405
00:20:31,631 --> 00:20:34,232
♪
406
00:20:34,234 --> 00:20:35,967
Unfortunately, this cave
got big enough
407
00:20:35,969 --> 00:20:37,802
That it couldn't support
the land above it,
408
00:20:37,804 --> 00:20:41,239
And what the video's showing
is the land collapsing down
409
00:20:41,241 --> 00:20:42,907
Into this empty salt mine.
410
00:20:42,909 --> 00:20:51,015
♪
411
00:20:51,017 --> 00:20:54,018
-- Captions by vitac --
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412
00:20:54,020 --> 00:20:57,021
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