All language subtitles for BBC.Deep.Ocean.Kingdom.of.the.Coelacanth.1080p.x265.AAC.MVGroup.org_Subtítulos01.ENG

OVER RADIO:
- Neptune, Neptune, Control.

- Go ahead, Control.

- Summer 2024.

- Neptune, you are all stop.

If you could move upslope to 118

and follow transect to the dock.
- Roger.

- An expedition is setting off in
search of a little-known fish

that lives in the deep sea.

Its fossilised skeletons have been
found in rocks

that are 400 million years old

and suggest that these fish could be
the ancestors

of all backboned animals, including
ourselves.

But their fossils disappear at the
same time

as those of the dinosaurs - 66 million
years ago.

Then, in 1938, a trawler, fishing off
the coast of South Africa,

made an astonishing catch.

It was undoubtedly the same kind of
fish -

a coelacanth -

but an hour or so earlier, it had been
alive!

It was a sensation.

A true, living fossil.

But little was known about how and
where it lived.

Now, a special expedition in a
state-of-the-art research ship

is setting off to try and discover
more about this living fossil...

- Nadir or Neptune?
- Ready for the water.

- ..and they hit lucky.

- Yeah. What's that?
- Ah! That's a coelacanth!
- OK. Coelacanth.

What's that? Is that a coelacanth?
- Wow!

- Yeah!
- Yay!
- Yeah, we found a coelacanth.

- There was a whole group of these
ancient fish.

- Oh, but look. Look how they're all
moving.

It's so crazy!

And look at the white tummy.

- They even witnessed for the first
time

what appears to be its mating
behaviour.

And the video recordings they made

shed light on how primitive fish like
the coelacanth

may have used their fins to walk on
land.

- It's just gorgeous.

And when we look at creatures like
this,

we see the evolutionary history we
share with fish.

- Join us on a journey to discover
more

about this mysterious survivor from
the very ancient past.

The island of Sulawesi in Indonesia.

BIRDSONG

It straddles the equator...

..and the waters around it

contain some of the richest coral
reefs in the world.

This is OceanXplorer,

a vessel specially equipped for
deep-sea research.

The team has special permission from
the Indonesian government

to spend two weeks looking for living
coelacanths.

The coelacanth is called raja laut in
Indonesia,

which means king of the sea.

They have a pair of powerful deep-sea
submersibles.

Each has a transparent dome

that will give it almost 360-degree
visibility.

And they are fitted with an 8K
deep-ocean camera system

specially developed for this trip.

The ultra-sensitive cameras are able
to record clear pictures

even in the darkest depths.

They will also use a large, unmanned
ROV -

a remotely operated vehicle.

- Whoa!

- This ROV is equipped with additional
cameras

and can film in all directions.

- Iwata. I'm a coelacanth man.

- THEY LAUGH

- I'm Kerry. I'm a coelacanth woman.

- THEY LAUGH

These are the lead scientists on the
expedition.

Dr Masamitsu Iwata has been carrying
out research on coelacanths

for over 20 years.

Having worked and dived in Indonesian
waters for over 20 years,

Iwata knows these seas very well.

- Wow!

I'm Kerry.
- Lovely to meet you.
- From South Africa.

- Cool.
- Yeah.
- Very good.

- Dr Kerry Sink first became
fascinated by coelacanths

when she was a child.

- To really see the seascape and the
terrain

is going to be an incredible
experience.

And I think what would be amazing

is to see a coelacanth eyeball to
eyeball.

- The team are planning to explore

the waters off the northern shores of
Sulawesi.

The area is renowned for its active
volcanoes

and frequent eruptions have created
numerous caves

and cavities on the seafloor.

An earlier survey found a steep
underwater cliff here,

which the team are keen to investigate
further.

As the sun rises, they're ready for
their first dive.

Both subs will be used,

so they can cover as much ground as
possible.

- OK.

- Just feet on there. Yep. OK.

- Welcome.
- Ooh!

- OVER RADIO:
- Neptune to discharge.

- MACHINERY WHIRS AND BEEPS

- Lifting now.

- Here we go. Coming up. Watch all
your stuff.

- The submersible, Neptune, with Iwata
on board,

is the first to be launched.

- Ready for the water.

Neptune, Nadir, full stop.

Comms are good, and you are clear to
vent when ready.

- Then they launch the second
submersible, Nadir,

with Kerry on board.

KERRY EXHALES DEEPLY

- Neptune venting now.

- Roger. We'll stop venting now. Have
a good dive.

- 100 metres.

- Leaving the creatures of the
shallows behind,

they head for deeper water.

They're now at a depth of 200m.

Deeper than this, it's pitch-black.

- Control. Control, this is Neptune.
Depth - 224 metres.

- BANGING
On, spotlights.

They now plan to search an area
roughly half a kilometre long.

But in this darkness, that is not an
easy thing to do.

They're searching for bright spots

that could be reflections from a
coelacanth's eyes.

There are two bright specks in the
darkness.

It's a carpet shark,

sitting motionless on the seafloor,
waiting for prey.

Meanwhile, Kerry's sub is scouring

a different section of the cliff face.

- Ah! Oh! Ah!
- Oh!

What's that fish?
- What is it?

- Jelly nose! Jelly noses. The crazy
ones.

- It's a jelly nose.

A rare kind of deep-sea fish

that, until recently, had never been
seen alive.

Its long, ray-like fins are thought to
be sensors

that allow the fish to feel its way
around in the darkness.

- I've never seen one before.

- Thresher shark's back.

- Oh, oh, oh. Shark.
- Shark. Yeah. Thresher.

- It's a thresher shark, with a
distinctive, long tail fin.

It's at least three metres long.

- I'll slowly come up towards him.

I'll just see how he reacts, OK?
- Yeah.
- Yeah.

- They appear to have entered the
shark's territory

and it's slowly circling the
submersible.

- Wow.

- THEY LAUGH

Two smaller fish have sought shelter
underneath the sub.

They don't seem in the least fazed by
such a strange contraption

and appear to be using it as a place
to hide from the shark.

- Whoa!
PROPELLER WHIRS NOISILY

- But suddenly there's a problem.

- See, it's different. See it
shimmering?

- Oh, I see.

- A strong underwater current has
stirred up the seafloor

and the particles of sediment are
obscuring the view.

It's no longer safe to continue.

They must return to the surface.

The area is known for its strong and
unpredictable ocean currents,

which can make underwater exploration
very dangerous.

The team have to be prepared for
setbacks like this,

but it's frustrating when their time
down here is so limited.

So why are scientists so fascinated by
the coelacanth?

It seems that these primitive fish

may have solved a long-standing
evolutionary mystery.

Coelacanths first appeared more than
400 million years ago,

long before the dinosaurs,

and they thrived in oceans around the
world.

It was thought that they became
extinct

at the same time as the dinosaurs, 66
million years ago.

Then, in 1938, fishermen pulled up
from the depths of the Indian Ocean

a specimen of this ancient fish that
was alive.

Its discovery stunned the scientific
world.

The coelacanth was not extinct after
all.

Then, in the 1950s, another specimen

was caught off the coast of Africa.

And I had the privilege of examining
it.

Its fins have long, fleshy lobes at
their base,

which make them quite unlike the fins
of any other living fish.

And there seems little doubt that...

In fact, the fins were so muscular

that it was thought it might use them
like simple legs

in order to walk across the seafloor.

Since those first discoveries,

scientists around the world have been
searching the deep sea

for a living coelacanth.

Then, in 1997, there was another
surprising discovery -

a coelacanth was caught far from
Africa, in Asian waters.

The discovery re-awoke interest in
this strange fish.

Three days into the expedition,

and the team have decided to try a new
strategy.

- And find those...find those points.

- Er...

The target depth is about, around 160.

- They have decided to concentrate
their search

to depths of around 160m,

which are rich in underwater caves

and where water currents are
relatively stable.

- Today is the day we're going to find
a fish.

- 50 minutes into the search

and Iwata notices some
interesting-looking rocks.

Clumps of them stand on the otherwise
even seafloor.

The sub approaches cautiously.

The cameraman has noticed something
between the two clumps of rock.

- Yeah. What's that?
- Ah! That's a coelacanth!

- OK. Coelacanth.
- Yeah, maybe.
- Maybe.
- Maybe.

- A closer look reveals a creature
hiding in the cracks.

- What's that? Is that a coelacanth?
- Wow!
- Oh, yeah.

- Yeah!
- Yeah, we found coelacanth.
- Yeah.

- The team are thrilled.

It's their first glimpse of a live
coelacanth.

Unlike the dead specimens,

the living coelacanth is a steely-blue
colour with light flecks.

- I can get us a little closer,

but if we just do a bit of filming
here...
- Uh-huh.

- ..so we don't scare it off, right?
- Yeah.

- RADIO:
- You found a coelacanth? Understood.
Marking location.

- Coelacanths?
- Yeah.

- They got there?
- Yeah.

Control, Control. This is Neptune.

Confirm coelacanths. Over.

- Wait for it.

- After half an hour,

the coelacanth emerges, giving them a
better view.

It's over a metre long.

- Oh, there it is in the cave. Got it.
- Yeah.

- The other team have found yet
another coelacanth.

- Great. That is pretty spectacular.

Thank you.

- This is the first time that anyone
has recorded

such a high-quality 8K image of a
coelacanth in its natural habitat.

Its large eyes are adaptations to the
poor light down here.

The fish are extremely sensitive

and can see quite well, even in
darkness.

Most animal species continue to evolve
in some way over time,

but, astonishingly, the coelacanth has
remained almost unchanged

for over 400 million years.

It has scales that shimmer in the
light -

a characteristic that doesn't
fossilise.

Its fleshy fins are far more versatile

than those of most fish.

They move in a coordinated way,
keeping its large body steady.

One of its oddest features is its tail
fin.

Like that of fossil coelacanths,

it has a little tuft at the end,

which it can move independently.

What function this could have still
baffles scientists today.

Perhaps it acts as a small rudder

and helps the fish to make tight
turns.

Or maybe it's an electro sensor

that helps it navigate in the eternal
darkness.

Much about this ancient creature is
still a mystery.

- We're back.

- APPLAUSE

- Congratulations.
- Hi. Congratulations.
- That was so cool!

- Yeah!
- Well done.
- We found it.
- Yeah.

- How the coelacanth survives at great
depths

still remains largely unknown,

despite efforts of scientists across
the world.

Deep-sea exploration is not only
challenging, but costly,

so every day is precious.

To maximise their chances of observing
more behaviour,

the team have decided to deploy all of
their equipment simultaneously.

- We are launching number two

before we are recovering number one?
- Yes, yes.

- That was the request, yes.

- Always an overlap.
- Yeah.
- Yeah.
- OK.

- OK.
- Thank you.

- The aim is to carry out continuous
observations for 72 hours.

It's an ambitious plan

and requires the crew to run the subs
in shifts, day and night.

This is a first, even for the crew of
OceanXplorer.

The scientists are now sure

that coelacanths stay dormant
throughout the day.

They suspect that the fish is
nocturnal,

so they start their daily shift in the
early evening.

- Control, control, this is Neptune.

I have cave in sight.

- This coelacanth is still in exactly
the same spot

as it was when they found it the
previous day.

But the team must be ready to respond
if and when it does move.

They know perfectly well that the
coelacanth,

to sustain its massive body, must come
out to feed sometime.

But it doesn't move, even at night.

As the team proves by speeding up
their video recording,

it remains in exactly the same spot.

At midnight, the second sub, with
Kerry on board, sets off.

She now takes over from Iwata in
keeping watch.

RADIO CHATTER

But even after ten hours, the
coelacanth has still not shifted

and shows no sign of wanting to look
for food.

Finally, at, eight in the morning,

the team decide to bring out the
unmanned ROV.

Kerry is exhausted.

They've now been watching the
coelacanth continuously

for 24 hours,

but it still has shown no sign of
moving.

Perhaps the sub's lights are making it
nervous.

So they switch to infrared lights

that are virtually undetectable by any
fish.

- OK, darkness.
- Darkness.

- BANGING

And still, the coelacanth does not
move.

At 7am the following day,

39 hours later,

it finally does something.

- Ah!

- Oh! We're on the move.

- Yeah. It's beautiful.

Maybe she's going out of it.

- The coelacanth, at last, is on the
move.

- We're supposed to follow her.
- Yeah.

- Shall we follow?
- Yeah.
- Yeah.

- It swims slowly,

but in a way that our scientists have
not seen before.

It propels itself forward

by moving its fins rhythmically from
left to right.

The two fins appear to provide forward
propulsion.

- Oh, it's steep here.

- Ahead is a vertical cliff face.

- It'll be interesting to see if she
goes up this crack here.

Right, she's going along the crack.

- The coelacanth makes its way
purposefully along the steep cliff.

- So, this is a good...

- Then it comes to an overhang in the
rocks.

- She's there.
- Yeah. She's here.

- That's perfect.

Yeah. We want to leave her somewhere
where she can maybe stay.

We don't want her going.

- Mark this waypoint...

..Big Mama's New House. Depth - 160
metres.

- The fish has disappeared into the
crevice.

The place where the coelacanth has
chosen to hide

is one the scientists had not
expected.

It's a large overhang in the cliff,
effectively an underwater cave.

Tracking the fish's movements has led
them to a new hideout.

This is a real reward for their
72-hour vigil.

Then, Kerry spots something else.

- Oh, I think I see another one.
- What?
- On the left.

- Wow!
- There. Is it?

Yes.

- There appear to be more coelacanths
hiding in the cave.

It's an extraordinary sight.

- One, two, three, four,

five, six, seven,

eight.
- Eight!

- Eight!
- Eight?
- Eight.

- What is happening?

- There are definitely eight
individuals,

and the team are astounded.

What could be the reason for such a
gathering?

- Spawning aggregation.

- It's hard to know why these
coelacanths have assembled

in such a tight space,

but they seem to be resting
peacefully, side-by-side.

Suddenly, the thresher shark
reappears.

The coelacanth retreat further into
the crevice.

The arched overhang provides good
cover,

allowing even a large fish like a
coelacanth to hide unnoticed.

The cave also provides protection from
ocean currents,

so there is little danger of being
swept away.

It's a fortress in the kingdom of the
coelacanth.

To help them get a better view beneath
the ledge,

the crew use another piece of
equipment.

- I'm going to take a bit of...

- It's a tiny underwater camera

that they manoeuvre into position and
attach to the rock face.

Despite its small size, it gives a
surprisingly detailed image.

They can just distinguish a coelacanth

huddling underneath the ledge.

Within minutes, swarms of tiny fish
appear.

They're lanternfish,

attracted by the camera's bright
light.

Once the swarm has dissipated, the
coelacanth comes into view again.

And then...

Slowed down, we can see what happened.

Faster than the blink of an eye,

it lunges for a passing morsel of
food.

This is very different from the
slow-moving, languid creature

the team had seen until now.

The footage clearly shows the
coelacanth feeding

in a manner only known to be used by
prehistoric fish,

until now.

Recent research has shown that this
way of feeding

is only possible because of the unique
shape of their skull.

It is, in fact, split into two halves,

which are connected by a special
hinged joint.

This allows the fish to widen its
mouth to more than 30 degrees,

enabling it to bite with the force
needed

to feed on hard, scaly animals or to
swallow particularly large prey.

Many ancient sea creatures once had
this kind of a hinged joint,

but the coelacanth is the only known
living fish

to still possess one.

So, at last, we're starting to unravel

some of the mysteries that surround
this ancient creature.

It uses its fleshy fins to propel
itself slowly through the water

and into narrow crevices,

but, when necessary, it can move
surprisingly quickly.

And the unique joint in its skull
allows it to open its mouth wider

than most modern-day fish are able to
do.

These ancient features have clearly
served the coelacanth well

for millions of years.

Recently, scientists have discovered

that coelacanths can live to be 100
years old.

In the deep,

it seems that it's the slow and the
steady that wins the race.

The scientific team are keen to take a
closer look

at the footage to solve a particular
puzzle.

- What?!

Ah! There, there, there.

Oh, beautiful.
- Yeah.

- Oh, wow!

- Its fins have a thick, fleshy base -

a characteristic feature of an ancient
group

called the lobe-finned fish.

The fins of most modern-day fish are
connected to the body

in a way that enables them to flap,

but little more.

The coelacanth's fins, however, are
much larger

and have a row of bones attached to
thick muscles,

which gives the fins much greater
strength.

This arrangement is also found

in the limbs of most land animals
today

and suggests they share a common
ancestor.

Scientists have long puzzled over

how animals first hauled themselves
out of the water and onto land.

The coelacanth may provide the answer.

Their fleshy fins may have led to
limbs with an upper arm,

a forearm and fingers and toes.

And that enabled the first backboned
animals

to crawl out onto land.

Whilst the evidence from the fossil
record is compelling,

it can't show us exactly how these
ancient creatures moved.

At the University of Chicago,

evolutionary biologist Dr Neil Shubin

has been trying to solve this puzzle
for years

and is very excited by the team's
discoveries.

- It's like it's a fish with arms.
That's what's amazing.

So the way they swim is with movements
of an arm.

They're doing this.

It's not just a little paddle.

It has bones inside that can move much
like our own arm bones.

Look at that turn around.

- A closer look at the footage reveals
some important details

of how the coelacanth uses its frontal
- or pectoral - fins.

It appears to rotate each fin,

as if it were trying to stroke its own
head.

Slowed down, we can see the movement
more clearly.

By superimposing the bone structure
onto the fin,

we can see that the bone bends at each
joint,

allowing for this wide range of
movement.

Even the scientists themselves are
surprised by this revelation.

- I haven't seen it like this, no.

I can make guesses, hypotheses,

about how those bones actually moved,

but I don't really have the creature
to look at.

I'm inferring it from a skeleton,

but when I see a video like this,

I begin to see a living creature and
how those bones are used.

So it allows us to interpret those
fossils in whole new ways.

As we study these fish,

we understand something about
ourselves.

I find that very powerful and very
beautiful.

And when we look at creatures like
this,

we see the evolutionary history we
share with fish.

- On land, these bony and flexible
structures supporting the body

would have then gradually evolved into
well-muscled legs.

Over time, those early limbs evolved
into many different forms -

sturdy legs for walking on land...

..light wing bones for taking to the
sky...

..and dextrous hands capable of
grasping.

They evolved to meet the needs of
different habitats

and, as a result, life on land became
rich and varied.

The coelacanth's fins led to limbs
suited to movement on land

and so paved the way for all
terrestrial life

and our own evolutionary history.

Whilst the coelacanth has shed
important light

on evolutionary questions,

we still know very little about how
the species lives.

Dr Kerry Sink is hoping to answer some
of these questions.

One of her main aims

is to find out more about the fish's
reproductive behaviour.

Coelacanths have white speckles all
over their bodies.

Each fish has its own unique pattern
and looks slightly different.

Kerry has used these differences to
identify individuals.

- I want to be paying attention to
what's happening from fish to fish.

So I've been taking careful notes
about which fish is which

and how they might be interacting.

- On this expedition,

one particular individual has
attracted Kerry's interest.

It's the female that she had followed
to the group under a ledge.

Kerry recognises it by a unique
feature.

- So the W mark is one of the most
distinctive marks

on the right flank of the big female.

- Kerry knows it's a female because of
its size -

females are larger than males.

She's keen to follow this female

to see if she can discover any
evidence of breeding activity.

Her sub prepares for another dive.

They have headed to the rock face

where they last saw the female
coelacanth.

- I haven't seen the W. Have you seen
the W?

- After 30 minutes, the female with
the W mark appears.

She is over a metre long

and because she's larger than the
others,

Kerry has nicknamed her Big Mama...

..and she continues to keep a close
watch on her.

Five hours later, the coelacanths
begin to do something

that the scientists have never seen
before.

Some of the fish begin to hang
vertically in the water.

- Oh, but, look - look how they're all
moving.

It's so crazy!

- Kerry believes that this may be
coelacanth courtship behaviour.

- I think we have mating coelacanths.

And look at the white tummy.

And they don't normally look like
that, right?

Very interesting behaviour.

- The coelacanths have turned their
undersides white.

Many fish change colour in order to
attract a mate,

and Kerry suspects that coelacanths
may also do so

to appeal to the opposite sex.

The team in the other sub

are also witnessing some interesting
activity.

One of the coelacanths is heading away
from the rest of the group.

It's heading straight for another fish

approaching from the other side.

The two fish begin to circle each
other.

Perhaps they're rival males, competing
for a female.

Back at Kerry's sub, Big Mama, with
her distinctive W mark,

is also being approached by a male.

He is clearly smaller than she is.

As he sidles up to her, he appears to
rub his head on her underside.

The researchers think that she might
also be producing

some kind of a pheromone that attracts
males.

He continues with this curious mating
dance

for over three minutes.

This is the first time that anyone has
seen

coelacanths interacting with one
another.

It's an exciting discovery that brings
us one step closer

to understanding their breeding
behaviour.

For Kerry, this is a career highlight.

- Just, like, deep gratitude

and something I've wanted for a long,
long time - 24 years.

I told the coelacanths, "Thank you.

"Thank you, thank you, thank you."

- Big hug first.
- So cool!

- Congratulations.
- Thank you.
- It's so cool.

- Thanks for making this happen.
- Of course.
- I'm so pleased!

- Although coelacanths have managed to
survive for 400 million years,

they now face a new threat.

- Oh, what's this?

- Oh!

- There is something drifting in the
water.

- Trash, I guess, maybe.
- Yeah, I think so.

- The team are shocked to discover
plastic waste,

even at these depths.

Throughout the expedition,

they found evidence of human waste
products littering the ocean floor.

- So many sandbags here.
- Yeah.

- The ancient fish now face a deep-sea
home full of our rubbish.

And a dead coelacanth has even been
found

with plastic bags in its stomach.

The coelacanths' home is often close
to human habitation.

Strong storms and typhoons

carry rubbish deep into areas where
the coelacanths live.

Today, our activities threaten the
home of this ancient creature

in all of the world's oceans.

The two-week expedition has come to an
end.

- The coelacanth is just really a very
special animal

that has this window into the past,

that has these really unique features

that inspire incredible curiosity.

For me, the coelacanth is also the
ultimate survivor.

And I was just experiencing amazement
and awe and gratitude.

- The expedition recorded many
important aspects

of the coelacanths' life for the first
time.

Its discoveries have helped us
understand a creature

that looks very similar to those that
lived 400 million years ago.

Hiding beside underwater cliffs,

it now has a slow and energy-efficient
lifestyle...

..and breeds unobtrusively.

As a species, coelacanths have
survived

all the environmental upheavals that
have transformed the planet.

Watching them has brought to life

one of the most crucial episodes in
the history of life -

when fish with stout, fleshy limbs

emerged onto the land for the first
time

and became the ancestors of all
land-living backboned animals,

including us.