01x03 - Sharks

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Just say "sharks!"
And everyone freaks out.

Are these creatures
K*llers of the deep,

Or is that hype?

On this episode, the guys
are going to dive, swim,

Get stranded
on a desert island...

Hey, anybody!
We need a ride!

Use state-of-the-art
technology

To find out
the truth about sharks.

This is an underwater adventure
with real teeth.

Got to like it!

[Whistle blows]

Iarriba!

Iandale, andale!

We're here
off south bimini
island,

Which is
in the caribbean sea

Off of florida--

The arrow
explains it all--

And we're searching
for those legendary
predators--

Sharks.

And martin's
gone underwater

To scope out
the scene
for some right now.

Martin!

Martin!

Martin!

Hey, chris.
How's it going?

Talk about contributing
to the stereotype

That's been plaguing
sharks for centuries!

[Announcer]
since the beginning of time,

The human populace
has been terrorized

By the evil death machines
of the deep.

Shark!

Shark!

Shark!shark!

[Chris]
talk about bogus!

Sharks have been
given a bad rap,

But not all sharks
are dangerous.

Even the ones
that aredangerous

Are only doing
what comes naturally.

We're here to discover
the truth about sharks,

Face-to-face.

How are we going
to talk to each other
underwater?

I've got it
covered.

All right.
The underwater
communicators.

[Ttark]
the "humans being terrified
of sharks" thing

Gets my gills up.

Sharks aren't scary.

What sharks are
is darn devonian.

Devonian? Sharks go back
to the devonian era?

That would mean...

Sharks are over


That's 200 million years
before dinosaurs. Wow!

That's what I call

One serious creature
accomplishment.

To get an idea of how long ago


Pretend this football field
isn't measured in yards

But millions of years.

The goal line
is where we are today.

Humans first appeared here,
some two million years ago.

Here at the other end
of the field,

Dinosaurs first appeared
some 200 million years ago.

To get to where
sharks first appeared,

You need more room.

Sharks made
their first appearance here,




Is a very long time.

Wonder what those sharks
looked like.

[Ttark]
they looked like this.

Sharks haven't
changed much.

They got sleeker, speedier,

But the shark has always been
one tough customer.

Wonder if chris and martin
have found any.

[Chris]
come in, tiger shark.
Anything in sight?

[Martin]
negative, hammerhead.
It looks pretty barren.

Wait, chris. There's
something up ahead.

I see it. Let's go.

Wow! Is it a shark?

[Chris]
no, but it has a lot
to do with sharks.

It's a remora,

Which is one
weird-looking fish.

The thing is,

If there's
a remora around,

There could be
sharks.

See that weird padlike
thing on its head?

That's a special fin
with a special purpose--

Sort of a suction cup
the remora uses

To latch onto a shark.

Martin, you see that?

What? Where?

Over there.

I thought I saw
something move.

You did see
something move!

It's a stingray!

Stingrays
aren't sharks,

But they are
related,

And like
their more famous
relatives,

Stingrays
can be dangerous

If you step on them.

On the end of
their whiplike tail

Is a stinger.

Stingrays and sharks
are both members
of the chondrichthyes,

Creatures whose skeletons
are made of cartilage,
not bone.

And if you're wondering
what cartilage is...

Cartilage is plasticky stuff
your ears and nose are made of.

It's rigid, but not solid.

Sharks' and stingrays'
tough skeletons

Are lighter
and more flexible than ours.

If our skeletons were made
completely of cartilage,

Leaning would be
impossible.

Whoa!

The things I do
to make a point.

Chris, I see
more stingrays.

Which probably means
there are rays around

We can'tsee.

Rays sometimes
bury themselves in sand

To hide from predators.

Then, when the time
is right, they fly out.

These rays do look
like they're flying.

It might look like
these stingrays

Are flapping their fins
like birds flap wings,

But they're actually
rolling their fins
like waves.

That way, they can
glide through
the water.

A lot of people think
stingrays are scavengers.

Not so.

Just like sharks,
they're hunters,

And they'll hunt
everything,
from fish to crabs

To that floridian
favorite--shrimp.

[Al]
shrimp? Wait a second.

Guys, there's another creature
not far from here

Who's big on shrimp.

[Martin]
flamingos get
their pink color

From the little shrimp
they eat.

Talk about
"you are what you eat."

There's so much carotene
in shrimp flamingos eat

That their feathers
actually turn pink.

If they don't get enough
carotene in their diet,

They'll turn white.

Did you ever wonder
what it would be like

To turn the color
of the food you eat?

Cool!

Fruit salad?

Guys, I have a lead

On where to find
sharks.

There's some
great shark habitat


South bimini island.

Figure out
how to get there.

We've got a plan!

[Together]
hey, anybody!
We need a ride!

[Motorboat approaching]

Hey! Hey!
Over here!

Woo!

Over here!

Hey! Over here!
Come on!

Come on!

What are you guys
doing on this island?

Looking for sharks.

We are, too.
Come along.

Can we come
aboard?

Come aboard!

One at a time.

Beautiful job.

Wow! You guys were
on that crazy rock.

We've been trying
to find sharks.
Where are you headed?

We're going
to triangle rocks,

And we usually
get them there.

What kind
of sharks?

Lemons,
caribbean reefs,
nurses--

Four or five
species--

Blacknoses,
sharpnoses,

Occasional
hammerhead.

Do you think
we could see
a tiger shark?

We might.

[Martin]
talk about convenient--

Being picked up
by a shark expert

When we're looking
for sharks.

But how many kinds
of sharks are there?

There's tiger sharks,

White-tipped reef sharks,

Tasseled wobbegongs...

Gray nurse sharks...

Catsharks...

Whalers...

And another 370 species
around the world.

But in these
caribbean waters,

We're likely to find
lemon sharks,

Nurse sharks,
and caribbean
reef sharks.

About 13 species
of sharks

Live around
bimini island.

Scientists like sam
track the sharks

To study their movements,
habits, and behavior.

Electronic transmitters
like this one

Are attached
to the shark's fin

Before it's released.

[Chris]
martin, sam and I have
picked up some activity.

Hold on. I'm trying
to pick up the signal.

[Chris]
we've got something!
I'm coming in.

Oh, man,
"activity" is right.

Martin,
do you see that?

Yeah.

Let's move out.

[Martin]
wow! It isn't a shark,
but it is huge!

A shipwreck!

Wow! Look at
all the creatures

That have made it
their home.

And why not?

[Al]
a sunken ship makes a great
habitat for sea creatures--

A place for coral, sponges,
and sea grasses to grow.

And there's
tons of fish
hanging around--

Puffer fish...

Goatfish...

Barracuda...

Yellowtailed jacks...

Angels...

Grouper...

It's amazing that
so many different
kinds of fish

Can cohabitate here.

I thought
of something else

These fish
have in common--

They're
all shark food.

Good call!
Chances are,
sharks are nearby.

Let's take it easy.

No sharks yet.

But there is a lot
of shark food around.

What do you think?

We've got to be
in shark territory.
Head that way.

Gotcha.

Chris, you see
anything yet?

Negative.
Whatever I saw
moved on.

I'm not sure
what it was,

But it was big.

Ah! I don't see
anything.

Let's keep going.

Maybe I'm wrong.

Maybe all I saw was...

Sharks!

Caribbean reef sharks.

These are one of
the more dangerous types,

And we're surrounded.

Martin! I can't find you!
Where are you?

Chris,
where are you?

All I see is sharks!

Right here.
This is incredible.

We're completely
surrounded.

This isincredible!

[Al]
wait a minute.

I thought sharks
were vicious K*llers.

Yeah,
but we're o.k.!

Looks like
these caribbean
reef sharks

Aren't bloodthirsty
after all.

No kidding.

It's actually really
peaceful down here.

[Chris]
look! We're not
the only ones

Hanging
with the sharks.

The remoras
found them, too.

That remora's
trying to latch
onto the shark.

Sharks are
a bus for them.

The shark takes them
for a ride.

That way they can
save energy

And pick up a free meal
along the way.

Looks like we found

Some primo reef shark
habitat.

Let's see who else
we can find.

Hey, martin,
look at this.

We've got
nurse sharks.

Nurse sharks
are bottom feeders.

That means
they prowl around

The nooks
and crannies

Of shipwrecks
or coral reefs

Looking for crabs,

Octopi, stingrays,
lobsters,
and lots else.

They're also
pretty harmless.

Martin, is that
what I think it is?

Where?

Over there.

Yeah, I see it, too.
Let's check it out.

What kind of shark
is that?


Moving fast,
has a pointy nose.

It must be...

A sharpnose shark!

I can't believe
we're so close
to it.

They're pretty
skittish.

[Al]
skittish is right.

From what I'm seeing,
they're more worried about you.

Man, how could anybody
be afraid of these guys?

[Chris]
we shouldkeep
our distance,

But still...

Martin, you notice
their skin?

It's like sandpaper.

That's because
their skin is made up

Of millions
of teethlike things
called denticles,

Not scales
like other fish.

It's like having
teeth for skin.

[Ttark]
teeth? Did I hear
someone say teeth?

Sharks' teeth are a subject

You can really
sink your incisors into.

Ugh!

They come
in every shape and size--

Small, spiky jobs
for munching little fish,

Serrated ones for tearing,

Humongo curved ones
for grabbing,

And blunt ones
for crunching shellfish.

Lemon sharks
straight ahead.

Copy that, al.

We see them,
and we're moving in.

Wow! There's a whole
group of them.

[Chris]
martin, I'm going
for a closer look.

[Martin]
I'm right behind you.

[Al]
lemon sharks are fast,
and they look fierce,

But they're not man-eaters.

They hunt crustaceans,
mollusks, and fish.

Chris, that lemon shark's
on the hunt.

[Clicking]

Hey, chris,
do you hear something?

I'm getting this weird
clicking noise.

Where did
the lemon sharks go?

I don't know.

Wait a minute!

Bottle-nosed dolphins!

Yeah!

Usually dolphins
avoid areas

Where sharks are,

Especially
when there's
only a few of them.

Yeah! Tiger sharks
eat dolphins, right?

So if dolphins
are swimming here,

Chances are
there are no
tiger sharks

In the vicinity.

Hey! Check out
the black-tipped
sharks!

Black-tipped sharks

Are one of
the commonest sharks
in these waters.

Like dolphins,
they travel
in groups,

And they've
been known to leap
out of the water.

How is your air?

I'm o.k.
How is yours?

Cool. We should see
what else is down here.

Think of all the sharks
we've already seen.

Lemon sharks...

Nurse sharks...

Caribbean
reef sharks...

Sharpnose sharks.

Black-tipped sharks.

[Al]
no kidding.

We've seen a ton of sharks,
but still,

You guys better be careful.

Remember, sharks
have amazing senses.

It's the electromagnetic-
wave trick.

They detect electronic signals
given off by other creatures.

It's not just sharks.
Remember the platypus?

This australian monotreme
swims with eyes and ears closed.

How does he get around?
His bill is supersensitive.

Touch sensors and electrosensors
help him navigate.

Sharks have that and more.

Sharks also have
the lateral line.

It starts at the nose
and goes to their tail.

It helps them feel
the vibrations

Of other creatures.

It's called distant touch.
Other fish have it, too.

That's how they can swim
in schools,

Everybody making
the same turn.

And now martin and I
are going to demonstrate

Exactly how
distant touch works.

I'm a shark,

And I'm
going to use
my lateral line.

The lateral line
allows him
to be more sensitive

To everything around him.

Hey, everybody knows
I'm a sensitive guy.

Think of me as a fish
moving through the water,

Giving off pressure waves--
these tennis balls--

Being picked up
by the shark's lateral line.

[Chris]
when the ball hits martin,

He knows where the ball
is coming from,

Like the shark can guess
where the fish is

When the pressure waves
hit him.

It's amazing how sharks use
all their senses to find food.

They use sight, sound,
touch, taste, and smell.

Sharks are first drawn to food
by sound and smell.

Then sight
and their lateral line

Helps them pinpoint the food.

Finally taste
and electroreceptors

Come into play.

See those tiny dots?

Those are electroreceptors,

And they are sensitive enough
to detect a fish's heartbeat,

So a shark can even find a fish
hiding in the sand.

If you get lucky,

You could find a tooth that fell
out of a shark's mouth.

[Al]
sharks are constantly
replacing teeth.

In a lifetime,
they may go through 20,000.

If humans could do that,

We'd clean up
from the tooth fairy.

Look how those guys
use their teeth and jaws.

A quick snap and...wow!

You know, you can't
deny that there are

Some dangerous
sharks out there.

Who's denying?
We're just saying
they're not evil.

We can get along
with sharks.

Chris, topside!

I think I see
sam's boat.

He's caught
something!
A shark!

It's enormous.

While we were diving,

Sam caught this giant
female tiger shark.

I've got a lot of questions
about tiger sharks.

What do they eat?

[Sam]
those things eat
anything they want,

But they really
specialize on things

Like sea turtles.

They can crush through
a sea turtle's shell?

They can saw through.

The jaws are loosely hinged
and work back and forth.

They're very big,
very powerful.

[Chris]
and getting very rare.

That's why sam's
using his research work

To help protect them.

[Martin]
so let's help him
and help the sharks.

[Sam]
are you ready?


Get it out
so I can see it.

Sam's trying to put a tag
on the dorsal fin,

And chris is helping
by lifting the shark.

These tiger sharks are huge.
They can weigh...

How much?

They can get to 20 feet

And weigh in excess
of 2,000-3,000 pounds,

But this one weighs
probably 350-400.

[Chris]
after sam and his crew
gather this info,

They tag the shark.

That helps them track it

And understand
their habits.

[Sam]
female tiger shark.
What's its total length?

[Woman]
total length--318.

[Sam]
very good. We're ready
to release this shark.

[Chris]
then they let the shark
return to the waters.

Our job is to get her swimming
to make sure she's all right.

She seems fine to me,

But we should give her
a final check.

O.k. She stopped to rest.
Let's do it.

[Chris]
the tag's fine
and in place.

Her reflexes are good.

That white lid
covers her eye

For protection
when she att*cks prey.

[Martin]
this is the jawprint
of another shark,

But she's breathing fine

And is ready to be released,
so untie the rope.

One final push...

She's outta here!

And she's looking good.

Some sharks
can be dangerous,

But most aren't
dangerous at all.

Once you
learn about sharks,

They're not as scary
as people think.

So maybe the ending
of our show should
look like this.

[Announcer's voice]
so the populace came
to the realization

That sharks were not the terror
they were believed to be.

Content in the knowledge
that all was well,

They could concentrate
their irrational fears on--

[Continuing in his own voice]
on the many creatures

They had yet to learn about.

Meanwhile, sharks
made plans to live

For another


In real life,

Sharks are nothing like
the monsters in the movies.

They're cool--perfectly adapted
to the life they lead...

And it's wild to think
they were already old

When dinosaurs
ruled the earth.

Let's hope they make it at least
another 400 million years.

Sharks may seem
pretty scary,

But they're
incredible,
beautiful creatures.

Remember
that sharks are also

A very important part
of the marine ecosystem.

An ocean full of sharks
is a healthy ocean.