04x09 - Polyp Power

[bunniefuu]

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We're here
in australia,

All set to check out

One of the greatest
construction jobs
of all time.

Leading us to it
is one--

There she is!

Hard to starboard!

[Martin]
that sea turtle
must be 400 pounds,

But she can really
fly through the water.

Turtles?

Didn't you guys do
a whole bunch of stuff
on turtles already?

Yeah, but this time,
where the turtle's going
is what we're interested in.

She's headed to one of nature's
greatest accomplishments.

It's all
on this episode of--

There she is again!
Hard to port!

It's all
on this episode of...

Iarriba!
Iandale, andalei

Ever notice that every time

I catch up
with chris and martin,

They're always in some
totally weird, new place,

And it's always the last place
I expect to find them.

I thought they were heading
off the coast of new guinea

South toward...

Not again.

Guys? Where are you?

Martin and I are here
off the east coast
of australia.

[Martin]
for days now, we've been
following this sea turtle,

Hoping that she'll lead us

To one of the great wonders
of the world.

Following
a sea turtle
isn't easy,

Even with a boat.

They can
stay underwater
for hours,

So you never know
where they're going
to pop up next.

[Martin]
they can travel
for 2,000 miles on an open sea,

And that's really amazing
when you consider

That some of them
can get up to 400 pounds.

There she goes!

[Martin]
where'd she go?

[Chris]
she scooted around
that piece of coral.

Come on.
She's back this way.

I think she's heading topside,
maybe for a nap.

[Martin]
yeah. That's right.

Some turtles sleep
while they float on the surface.

That's cool.

Hey, martin! Wake up.
We're almost there.

I'm still having trouble
tracking you.

I got
the eastern australia part,

But you still haven't told me
where "there" is yet.

"There" is here,

At the greatest
construction job
of all time!

The greatest construction job
of all time?

We're supposed to be
investigating creatures, not...

The greatest construction job
is in australia?

I don't get it.
What are you guys talking about?

What we're
talking about

Is bigger
than the great
pyramids...

The great wall
of china...

The empire state
building.

It's a conglomeration
of about 3,000
coral reefs,

Including 300 keys,
or islands.

It stretches
for 1,250 miles

Along
the australian coast

And can even be seen
from space.

It's called...

It's called...

[Dramatic music plays]

[In unison]
the great barrier reef!

[Chris]
one of the largest
living life-support systems,

And it's been growing
for 17 million years!

[Martin]
did you know modern humans
have only been around

For 40,000 years?

The reef attracts millions
of creatures, and how?

[Chris]
with its utterly
unique ability

To provide food and shelter.

[Martin]
so many creatures live here!

It would take years
to count them all.

[Chris]
underwater...

[Martin]
on the islands...

And in the air...

[Chris]
even creatures
who don't live on the reef

Come to check it out.

[Martin]
and now it's our turn.

There are thousands
of species of animals
of all sizes

That live
just down below.

Some are so small,
you need a microscope
to see them.

[Chris]
and some are as big
as 6-foot-long sharks!

And there's only one way
to meet these creatures.
Ready?

Ready.

[Chris]
this place is awesome!

[Martin]
there are so many creatures
down here.

Chris, look--an eagle ray.

Groupers!

Great barrier buildup!
What happened?

I go away, come back,
and everything's gone crazy!

You know,
a few million years ago,

That reef was just
a few ambitious polyps

Hanging out
in shallow water.

What?

[Ttark]
not what. Who!

[Martin]
ttark's got it.

Who isright...

[Chris]
because when we
talk about the reef,

We're talking about
all its creatures.

[Martin]
the reef is like a city,

A really complex
and intricate city.

[Chris]
man, it's busy down here

With all these creatures
living together,
doing their own thing...

[Martin]
and competing!
Chris, look at these crabs!

[Chris]
they're really
duking it out.

Crab fights are tough.

[Martin]
and there's even more
to the reef than a crab fight.

There are strange and unusual
creatures down here,

And sometimes
it's hard to tell

Which is a plant
and which is an animal.

[Chris]
it's not hard to tell.

[Martin]
oh, yeah?
Care to take a test?

[Chris]
all right.

Here's a moray eel--

Definitely animal.

[Martin]
here's another animal--
a painted crayfish.

Ah, but that's too easy.

[Chris]
and this huge clam.
Now, that's a lot of animal.

[Martin]
watch out, chris--
a jellyfish!

These guys can pack
a mean sting.

Whoa! Anemone!
Plant or animal, chris?

[Chris]
I'll go with animal.

[Martin]
all right!

[Chris]
hey, I know this stuff,

And that's turtle weed--
plant.

O.k., Now, here's a tough one
for you, martin.

Check out the sea cucumber--
animal, plant, or vegetable?

[Martin]
this might sound crazy,
but I'll say animal.

[Chris]
yeah, and I love
how they eat.

They suck sand in one end,
take the nutrients,

And pump the rest out!

[Martin]
o.k. Back to you, chris.
Plants or animals?

[Chris]
they look like bags,

But they're ascidians--
animals.

So are sea whips
and other soft coral.

[Martin]
now, I know these look
like underwater flowers,

But they're actually polyps.

Can you believe
that these are the animals

That built the reef?

[Allison]
hold it!

This isn't possible.

I'm supposed to believe
that those tiny creatures

Built a coral reef
over 1,250 miles long?

Magnification times four.

Oh, wow.

I didn't even know creatures
could look like that,

Let alone build anything.

Sort of look like upside-down
jellyfish, don't they?

I mean, they're so small
and weird-looking.

[Ttark]
what are you
talking about, al?

Sure, these polyps
look puny.

Sure, they look weird,
but they're big-time builders.

Let me show you, like this.

We're talking
a very simple guy here.

A coral polyp is made up of
tentacles, mouth, and stomach.

Who needs more?

When some good-looking munchies
go floating by,

The polyp's tentacles grab it,
nail it with a little poison,

And pull it
into its mouth,

And it's a one-way trip
to the old stomach.

[Allison]
wow! I didn't know you knew
so much about polyps.

[Ttark]
hey, coral polyps and I
are tight.

There's tons of polyps
out there,

And I'm buddies
with each and every one of them.

So, just how many
different polyps
are there?

[Martin]
a lot, and different species
form different-shaped coral.

There's staghorn...

[Chris]
mushroom.

[Martin]
you have brain...

[Chris]
plate...

[Martin]
and gorgonian.

Now, the colorful parts

Are the living coral polyps.

[Chris]
can you believe
it's these puny guys

That built a reef this huge?

Coral polyps are
the most amazing creatures
on the face of the earth!

How come no one ever told me
about them before?

I mean, they built
the great barrier reef.

For humans to build anything,
we need all sorts of things--

Some really well-laid plans,
a strong framework,

All those beams and cement
and bulldozers and dump trucks
and wood and steel and cable...

And nobody
could build it alone.

Just think of the polyps
in relation to the reef.

We're talking
about building something
a lot bigger than yourself.

Look at it this way--
I'm a polyp, and I want to build
a building as tall as the reef.

I'd be making a building


That's some construction job,
all right.

Even if I could build something
that much bigger than me,

Think of
all the cement I'd need.
That's a lot of cement.

Cement?
Polyps don't need cement.

They've got
calcium carbonate.

Let me see if I can explain,

Because it's amazing.

The coral polyp
makes a skeletal cup

And latches himself onto all
the skeletons of his ancestors.

Boy, talk about having
skeletons in the family tree.

Cool! So it islike
how we humans build.

Polyps and humans
both use a type of cement.

Cement schement!

This guy cranks away
and builds his own
little cup-like home.

Then his buddies crank away
and build their homes
on top of his,

And so on and so on,
until, before you know it...

Bravo! Bravo!

All those skeletal cups
have become the coral reef.

Now, that's how you build
the ultimate creature city.

[Chris]
the coral reef
looks really complex,

But when you break it down,
it's pretty simple.

[Martin]
first you have the coral.

It's the reef foundation,

And you know who it was
built by--the coral polyps.

[Chris]
next you have the plants.

You might think you're
just looking at fish here,

But there are zillions
of tiny plants

Floating around the reef
that you can't even see.

[Martin]
then you have herbivores.

[Chris]
those are
plant-eating creatures.

[Martin]
but they have to
watch out for...

[Chris and martin]
carnivores!

[Chris]
carnivores are the hunters,

And the best in the field
is the shark.

[Martin]
the reef is home
to all different kinds.

Chris, check out
this epaulette shark!

He's walking through the reef
on his fins.

Wild.

[Chris]
and the nurse shark.

[Martin]
is that a white-tipped
reef shark?

Whoa.

[Chris]
life around the reef
is incredibly diverse.

Look at all the shapes,
colors, sizes, and patterns.

Check this out!

All these fish
look different

Because they have
different life styles.

[Martin]
and they all have different ways
to protect themselves, too.

Let's take a close look.

[Chris]
can you see the fish?

Now, that's camouflage.

This lionfish
has a deceptive defense, too.

A fish might think
his fins are soft...

[Martin]
but they conceal
poisonous barbs. Ouch!

[Chris]
and the puffer fish.

When threatened,
he puffs himself up
to look bigger.

[Martin]
that makes him look
too big to swallow.

[Chris]
check out the trumpetfish.
This guy is weird.

[Martin]
he's so long and thin,

He fools predators into thinking
he's a piece of the reef.

[Chris]
and smaller fish?

Their best defense
is to travel in schools.

[Martin]
different sea creatures
have different ways

Of moving through the water.

[Martin]
here's a cool
creature relationship--

The anemone and the clown fish.

[Chris]
they hang out together.

Now, the anemone's tentacles
are deadly,

But lucky
for the clown fish,

He's protected from them
by a mucus coating.

[Martin]
so he doesn't get zapped,

And the clown fish uses
the anemone as a hideout.

Oh, my gosh!
A fairy basslet!

Now, these fish are strange.

The male is purple,

And he hangs out
with a group of yellow females,

And what's really weird
is if he dies,

The lead female
changes her color and her sex
and takes his place.

Chris? Martin?
I just saw something
really weird back there.

To your left, the coral
doesn't look right.

Go check out
that part of the reef
to your left.

[Martin]
allison's right.
Something is wrong down here.

[Chris]
definitely.
Do you see what I see?

[Martin]
do you see what I don'tsee?
Fish!

Where are all the fish?

What is it?
What's going on?

The great barrier reef
is like an underwater
rain forest--

It's just
full of life.

[Martin]
but if anything
happens to the coral,

Then the whole system
is thrown out of whack,

And all the creatures
that depend on the reef
are in trouble.

And you know what?

Down there,
something is
k*lling the reef.

k*lling the reef?

Wow. It says here
that 85% of the coral
and most of the fish

From around some of the islands
in the great barrier reef

Are being k*lled off.

We have to find out who or what
is hurting the reef.

Of course, there are
a ton of creatures down there.

It's hard to know
where to start or with who.

How about a creature

That most people don't even know
isa creature.

This is something you
might think only exists
in your kitchen,

But there are real,
living, breathing sponges

That live right here
on the reef.

[Chris]
some sponges are hard,

And others are soft
and spongy.

Some burrow in
and dissolve living coral.

That's called coral bleaching,
and it can be hard on the reef.

[Allison]
but it can't be a sponge
hurting the reef.

According
to the creature computer,

Sponges help keep coral together
in deep water.

I'm crossing sponge
off the list.

Maybe it's...
Chris? Martin?

I'm hearing something weird
like crunching.

What could crunch
underwater?

[Chris]
well, there's an emperor fish,
but he's a pretty quiet guy.

And those cromis and damselfish
aren't making a lot of noise.

Those hussars look like
they're hiding.

I wonder, from what?

Unless...there's a...

Wait a minute!
There it is!

There's a fish down there
eating coral.

It's a parrotfish.

It's hard to believe
that a fish can actually survive

On polyps and algae,

But the parrotfish does.

[Martin]
yeah, but what's with the name
parrotfish?

[Chris]
well, look at his mouth.

[Martin]
hey, you're right!

It looks like a parrot's beak,

And he needs that beak
to crunch coral.

[Chris]
and do you know about
the parrotfish's sleeping bag?

[Martin]
his what?

[Chris]
he makes a sleeping bag
out of mucus.

[Martin]
wow! That's wild!

[Chris]
and that keeps him
from being smelled by eels!

And then he can go to sleep.

So we've got
the creature culprit.
It's the parrotfish!

[Ttark]
careful, al.

Ttark, he crunches coral.

You're telling me
he's not the culprit?

Aw, give the parrotfish
a break.

So he crunches polyps.
He's got to eat, doesn't he?

Just because he eats coral
doesn't mean he's
k*lling the reef.

Trust me, al. I know the guy.
I've swam with the guy.

I've even crunched coral
with him,

And I'm telling you,
he's not the creature culprit.

There's no one creature
doing all this,

Because the reef
is all about balance.

[Martin]
hey, chris--a cleaner fish.

This guy is eating parasites
off of that big fish.

The big fish gets cleaned.

The small fish
get a parasite meal.

[Chris]
over here!

See that fish
hanging on the shark?

That's a remora.

He hangs on and gobbles up food
that the shark drops.

This may seem
kind of weird at first,

But when you think about it,
we humans do the same thing.

[Slurred speech]

What martin's trying
to say is that it's
just another example

Of how creatures
cooperate with one another,

And here's
another great example.

[Screaming]

[Chris]
rays.

They hang around
between coral patches

And forage the floor
for small creature meals.

[Martin]
some rays bury themselves
in the sand on the ocean bottom.

They do this to hide,

And they do it so well that
predators, like tiger sharks,

Swim right over them
without even noticing.

Hey! Watch it!

[Martin]
this is great--
swimming with the rays.

[Chris]
but time's running out,

And we still have to figure out
what's k*lling the reef.

[Allison]
o.k. So here's the problem.

What could be big enough
to wreck large parts of the reef

And spread like a forest fire?

I think we're talking
a really unusual creature here,

And I think I know
who it is--

The crown-of-thorns starfish.

[Martin]
there it is--

The crown-of-thorns
starfish.

[Chris]
and the coral around it
is dead.

[Martin]
could it really be the k*ller?

[Chris]
could the crown-of-thorns
be k*lling the reef?

[Allison]
if the reef's in trouble,
doesn't it mean

All the other creatures who live
underwater are in trouble, too?

I mean,
for underwater creatures,

The reef is
a whole life-support system.

[Ttark]
but, al, the reef
also provides a home

To creatures
above the water.

[Allison]
I see what you mean.

All the other little islands
are made of coral, too.

And the number of creatures
that live on a coral island

Is staggering.


Black notty terns nest here.

They live in a huge colony,

And they're everywhere!

[Chris]
it's like a big city,

And people thought they
were the first to invent
apartment-style living.

[Chris]
ah, don't worry, martin.

[Martin]
easy for you to say.

You don't have bird poop
on your face.

So if the reef's threatened,
all the reef creatures
are threatened,

Not just
the ones underwater.

I mean, birds can't nest
if there are no coral islands,

Can they?

And if
the crown-of-thorns starfish

Is preventing new reefs
from forming...

So a crown-of-thorns starfish
is eating away at the reef.

It's supposed to.
That's what nature's all about.

[Allison]
hang on a second.

Look, it's the greatest
construction job of all time,
and if it's destroyed...

[Ttark]
don't worry, al.

[Allison]
you're going to tell me

That everything shifts
in the creature world, right?

That it's a balancing act?

[Ttark]
actually, I was going to say,
"stuff happens. Get used to it."

But, uh, that will do.

Another thing I could say is...
Look out behind you!

I don't get it.
This part of the coral
looks o.k.

Sure, it does
because it's new coral.

New coral?

So the crown-of-thorns starfish
isn'tthe culprit.

How can that be?

[Martin]
coral reefs
have dealt with

The crown-of-thorns
starfish for thousands
of years,

But what the reef
isn't used to is
the impact of people.

I didn't even think
to check for humans

As possible destroyers
of the reef.

Pesticides, reckless boaters...

Of all creatures, humans do
the most damage to reefs.

You know, we've got to take
a lot better care of our reefs

Because this
is really bad news.

[Martin]
but there ishope.

While some parts of the reef
might be dying,

There are always
new parts being built.

It may take
a few thousand years,

But all good things
come with time.

Let's go.

[Martin]
the great barrier reef

Is an amazing
piece of construction.

[Chris]
and as long as we
take care of the polyps,

It's sure to last
a long, long time.

[Allison]
when we say we love nature,

It seems we always mean
something big and fluffy,

Like a lion or a monkey
or something,

But when you think
of a coral polyp

And all it can do
and has done...

You really appreciate

Another side
of the creature world.

Great things
come in small packages.

[Chris]
it would take years
to really look at

All the creatures
down here.

[Martin]
but we only have 10 minutes
of air left in our tanks!

[Chris]
oh, man. We got to move.