All language subtitles for Komodo Secrets of the Dragon BBC Natural World 2011 1080p HDTV x265 AACForum EN Sub

This is the Komodo dragon.

The biggest lizard on the planet.

Science discovered the dragon
just 100 years ago.

But the giant's story
extends across millions of years.

The dragon has long been seen
as a prehistoric creature

from a lost world,

and we're beginning to realise

there's far more to this lizard
than meets the eye.

Today, scientists are teasing
secrets from the dragon

by delving deeper into their lives
than ever before.

As you can see, it's destroyed

the ability of the blood
to form the blood clot.

There's something in their mouth
that affects the blood coagulation.

And with modern technology,
they are able to see the dragon

in a completely new light.

I would say that the Komodo is
a more sophisticated killing machine

than lions and tigers.

A century on since
its scientific discovery,

we're just beginning to uncover
the secrets about the dragon

that reveal this lizard as
a true wonder of the natural world.

The largest lizard in the world
attracts a lot of attention.

Around 40,000 people come to
Komodo National Park every year

to see the legendary dragon.

Their home
is an extraordinary place.

Where else in the world
would a tourist be allowed

to stroll alongside a top predator?

One known to kill humans.

The dragons are named
after the Indonesian island
where they were first discovered,

but we now know they are also found
on several neighbouring islands.

Together, these are home
to some 4,000 dragons.

It's not just tourists who have
beaten a trail to see the dragons.

Over the last 100 years, scientists,
filmmakers and explorers

have staked their reputation
on the big lizard.

Today, the dragon has become
something of an obsession

for this man,
Australian biologist Dr Bryan Fry.

A leading authority on snakes,

Bryan recently turned his attention
to the hunting strategy of lizards.

He has a hunch that there's
a lot more to discover about
the way dragons kill their prey,

and a visit to the island of Rinca

will allow him to study dragons
in the wild.

Hello, sir.
Hi, good morning, how are you?

Bryan. I'm Kevin.

Kevin, a ranger with
Komodo National Park,

will be showing Bryan around
the island.

But first, there's the crucial
matter of health and safety.

So how do you use the sticks?

We just use the stick to push
the dragon around the nose.

He will feel sensitive and run away.

Dragons often gather
round the rangers' huts,

using the shade to keep cool.

And they are as inquisitive of
people as people are of them.

Luckily, Bryan's stick

is an effective deterrent
against this nosy dragon.

You can see the huge throat
that they have.

Komodo dragons and other monitor
lizards have a bone in their throat

they use to inflate their throat out,

and that's one of the things
that allows them to swallow
such huge meals.

They can eat up to 80% of their
body weight in a single serving.

Satisfying their big appetites
seems low on today's agenda

for these docile dragons.

We have five Komodo dragons here

and they're all just -

oh, this feels nice - laying down
on this nice, cool earth.

Out in the sunshine
it's about 105 degrees.

In the shade here,
it's still about 90.

So they're moving back and forth

in between the sunlight
and the shade to cool off.

And just laying down like this,
it feels really nice.

You can see the big, big tail.

If he slapped me with that tail,
it would probably break my cheek.

But they don't think that I'm food,
they don't think I'm a threat,

so they're just watching me.

But I have my trusty little stick
here in case things go awry.

They look like they're just sleeping.
Stand up, run away!

If you're going to get
close to dragons,
you must be able to move fast.

Luckily, this is just
a small skirmish
between two tetchy individuals.

In dragon society,
big means powerful.

So when two heavyweights of roughly
equal size come together,

there can be only one outcome -
a fight.

Only when dragons fight
do you get a real sense of
their power and size.

For many years following
their scientific discovery,

we had no idea
how big these dragons could grow.

We now know the biggest males
can grow to over three metres

and weigh up to 100 kilos.

To get a better idea
of where the dragons are hunting

and what they are killing,

Kevin and Bryan must head away
from the rangers' station.

Dragons are often found
around waterholes,

where they cool off
in the heat of the day.

During the dry season,
water becomes a rare commodity

and must be shared
with other beasts.

Although they get most of the water
they need from their food,

they will top up
with an occasional drink.

But waterholes
are also a perfect spot

for dragons
on the lookout for lunch.

It's late afternoon,
it's really hot.

The buffalo are here to escape
the heat and it's a good opportunity

for a Komodo dragon to come down
and do a bit of hunting.

It's not just the buffalo,

but the pigs and the deer will also
be coming down to have a drink

and you often find
Komodo dragons, particularly
in the dry season like this,

hanging around the waterhole, just
like if you were in South Africa,

you'd find the lions circling the
waterhole or crocodiles in the water.

On the surface, these animals
don't seem particularly cunning
or calculating,

but anecdotal evidence
suggests dragons are smarter
than the average lizard.

They are keenly aware of
everything going on around them,

even when their eyes are shut.

Komodo dragons are extremely alert.

It's easy to confuse lack of
movement with lack of awareness.

He's not missing a thing.

I'm sitting here
playing a little game with him

where, when I open my eyes,

he's closing his eyes
and pretending to be asleep.

But the minute I close my eyes,

he pops his eyes open
and starts checking me out.

So he's just pretending
like he doesn't know I'm here
or doesn't care.

But as soon as I pretend to
go to sleep, he opens his eyes.

Gotcha!

They're able to think,
they're able to almost plot a bit.

They're more like
a mammalian predator,

so they're much, much smarter than
you'd give them credit for normally.

As cold-blooded reptiles,
dragons can sit for hours

assessing the situation
around the waterhole,

waiting patiently
for the perfect opportunity.

Water buffalo were introduced
to these islands by Dutch colonists.

The heaviest weigh in at a tonne,

a hard catch
for even the biggest dragons.

But a lame buffalo is
an entirely different proposition.

Dragons have an incredible
sense of smell,

using their forked tongues
to taste the air for odours.

It's thought they can even
detect a pregnant buffalo
by the smell she emits

and will follow her relentlessly,

devouring her calf
as she gives birth.

So the smell of a bloody cut

to a buffalo's leg
is enough to rouse their senses.

And with excellent eyesight,
they can easily distinguish

the lame from the healthy.

They can quite literally
smell the buffalo's weakness,

and several dragons soon circle
the hapless animal.

Each bite, when it happens,
is quick and glancing.

The dragons
are not working as a team.

Each dragon is acting alone,
in its own interest,

though when the buffalo
finally dies,

the meal WILL be big enough
to share.

The most remarkable thing
about this scene

is that no other lizard on the
planet is able to kill in this way.

The dragon has somehow broken ranks
from other lizards

to become a killer of prey
much larger than itself.

Bryan and his colleagues believe
this evolutionary leap happened

not in here in Indonesia
but thousands of miles away

in Australia.

This is a paradise
for monitor lizards,

close relatives of the dragon.

20 species live here, and they
come in all shapes and sizes.

The monitor lizards include

some of the biggest
natural predators in Australia.

And there is one particular
Australian monitor that provides

an important connection
to the dragon.

This is the Australian lace monitor.

It's the closest living relative
of the Komodo dragon.

You can see the close relationship
in the features that they share.

They both have scales with
little bits of bone inside of them.

They've got the long tongue
with the exquisite sense of smell.

There's a lot of misconceptions

about the lace monitor
and the Komodo dragon

where a lot of people think of them
just as scavengers,

but they're actually
very efficient predators.

Any good predator will
certainly scavenge a prey,

but just because they eat carrion
and other dead prey

doesn't mean that they're not very
adept hunters in their own right.

The way a lace monitor lives today
gives us an idea

of how the Komodo dragon's ancestor
hunted prey millions of years ago.

The lace monitor
is an agile tree climber.

Its long claws allow it to grip
the smooth gum-tree bark.

This particular tree has attracted
the attention of a lace monitor

because it's the home of a female
possum with babies in her nest.

POSSUM HISSES

The possum's noisy defence
forces the monitor to retreat.

But hunger drives the lizard
to make a second attempt.

Lunging into the possum's nest
looks suicidal,

yet the monitor seems
hardly to notice the possum's bite.

It takes less than a minute
for the lizard to devour

the baby possums inside the nest.

It's not hard to imagine a smaller
ancestor of the Komodo dragon

hunting in trees
just like the lace monitor.

But at some point in Australia's
past, this all changed.

Some monitor lizards became big -
very big.

Palaeontologist Scott Hocknull
has been piecing together
the past lives of these reptiles.

The evidence comes in tiny fragments
but, like a jigsaw,

builds a picture of a lost world
of giant lizards.

What I have here is Megalania.

This is the largest lizard
to have ever lived.

It's about five metres long,
maybe even getting to six metres,

so it's an absolute monster
of an animal.

Found in Australia,
lived between

about 500,000 years ago
and 50,000 years.

As well as the giant
Megalania fossils,

Scott has found evidence
of another large lizard -

not as big as Megalania,

but certainly bigger than any other
lizard living in Australia today.

Originally it was thought that
these bones

were simply a small Megalania,
a small individual.

But when we look at the bones
carefully

you can tell
that they're actually from adults,

so they were fully-grown.
So what that shows is that

it was
a completely different species.

When we compare the bones
of this animal

to all of the living
and extinct monitor lizards,

all the fossils that exist,
what we see

is that it's very much the same as
a Komodo dragon.

In fact, it's so similar,
it's the same species.

So this is concrete evidence
that in Australia, Komodos existed,

they lived four million years ago,

and it's most likely
that they originated here.

Prehistoric Australia
was full of giants.

Back then, prey animals
were dangerous quarry

because of their size.

To catch big prey,
it helped to be a big predator.

The standard body shape of a regular
monitor lizard became super-sized.

The Komodo dragon was one of
the most successful of these giants,

evolving from a smaller ancestor
into a giant predator.

Today, Australia
is no longer home to giants.

At some point, they disappeared.

Around a million years ago,
Australia began to dry out,

and, as its forests contracted,

the dragon population
slowly dwindled.

But some found a new home
further north.

Back then, a land bridge linked
Australia to part of Indonesia.

But the islands where dragons
live today

were never joined to a mainland.

There was only one way

dragons could have reached
the central Indonesian islands.

By swimming.

For a three-metre-long animal
weighing 100 kilos,

the dragon is a very good swimmer,
able to cross deep-water channels.

The first migrant dragons that
reached these central Indonesian
islands would have been in paradise.

No other predators lived here, so
that meant no competition for food.

But for every castaway
washing up on a beach,

there is the possibility it will
spend the rest of its life alone.

So how did these Robinson Crusoes
of the dragon world

actually establish a population
on these islands?

It's only recently
that we've discovered

another extraordinary secret
about the dragons.

In extreme situations, females
can reproduce without a male.

It's a phenomenon that in a human
would be seen as miraculous.

Somehow, the dragon's body senses

that normal conception isn't
possible, and her dividing egg cells

effectively create
a sperm substitute,

enabling her
to fertilise her own eggs.

For stranded dragons,
it's a regular part of their
desert island survival kit.

After almost eight months
of incubation,

dragon eggs hatch deep underground.

Their first instinct is to climb
upwards and out of the nest.

These first few moments
in their lives are perhaps
the most dangerous.

Staying on the ground makes them
vulnerable to predators,

and that includes bigger dragons
on the lookout for a small snack.

So the hatchlings must quickly
head up into trees for safety.

Young komodo dragons
are lithe and agile

and bear little resemblance
to the lumbering adults

that stalk the ground beneath them.

But as they grow up, they eventually
come back down to the ground

and transform into bulky giants
ready to hunt big prey.

It's easy to see why locals
call the dragon a land crocodile.

But despite its size
and bruising appearance,

there is one part of the dragon
that is nowhere near as strong
as a crocodile's.

Its head.

If you look at the skull,

it's actually quite small
relative to that massive body

and that's because they need
a very lightweight skull

in order to move fast when they're
chasing down their prey.

And the speed at which they
can swing their skull

while running is amazing.

They're very, very agile animals.

We're only just discovering the
remarkable, complex relationship

between the design of the
dragon's skull and its killer bite.

Bryan Fry's colleague, Stephen Wroe,
has examined the skulls

of many top predators.

He's created a computer model
of a skull based on a real dragon.

In this case, we were
fortunate enough to have

a whole specimen of a komodo dragon

and we were able to actually
dissect the muscles out

and come up with estimates

for the cross-sectional area
of the individual muscles.

So that allows us to get a pretty
good estimate for the sort of forces

that this animal would be able to
apply in the jaws.

By recreating how a dragon bites,

he's revealed a serious weakness
in this animal's jaws.

Its ability to bite down very hard
just using its jaw muscles,

its skull's not really well adapted
to do it.

The red and white colours
indicate stress, and clearly show

that a dragon biting down hard
could easily break its jaw.

Its bite forces themselves are weak.

For an animal of its size,
it has a very weak bite. In fact,

by our predictions, they're smaller
than that of an average house cat.

Despite its super-lightweight
skull,

the dragon is able to kill prey
weighing up to a tonne.

The secret to its success
is in the way it uses its skull.

Hidden inside its mouth
are 60 amazingly sharp teeth

that wouldn't look out of place
in the mouth of a great white shark.

Each tooth is backward curved
and serrated,

making them ideal slicing tools.

But to really take advantage
of its weaponry,

the dragon has to bite
in a very precise way.

When it bites in,

the head comes in at a slight angle.

It then pulls back

and, in doing so, it basically
uses a can-opening motion,

so it's using leverage around
its body instead of just its jaws.

That helps drive the teeth in
and cause major damage.

So it's not the jaw muscles
themselves

that are doing
the serious damage here,

it's the very powerful forearms

and shoulders that are really
driving this whole process.

And it's actually
a very clever use of leverage.

Scientists have called this
the "grip and rip" bite.

The dragon uses its sharp teeth
and muscular body

so it doesn't need
a heavyweight jaw.

It's a combination that allows the
dragon to be a fast ambush hunter

with one of the best killer bites
in the animal kingdom.

With a big dragon like this
and a water buffalo,

they can kill them but it takes
repeated bites over several days.

What happens is that
when they do the grip and rip,

they'll do that several times
and every time they catch up
with the water buffalo

they'll hit him again, and this
will leave more and more wounds
on it, and they'll keep bleeding.

But with something much smaller
like a deer or a pig,

90% of the attacks are fatal

and, in fact, 75% of them don't even
survive the first contact.

The majority of them
will die immediately,

some will last three or four hours

but only 10% of a natural prey item
will survive the initial attack.

Those are the kind of numbers
that a lion would love to have.

The fact that these giant lizards
are able to kill
so quickly and efficiently

makes living alongside them
a little worrying.

If dragons are meant to
keep out of villages,

someone has clearly
forgotten to tell THEM.

And the temptations of village life
are all too obvious.

Bryan is keen to find out more
about the difficulties
of living with dragons,

so Kevin is taking him
to the local police station.

Hello. Hello.

THEY SPEAK INDONESIAN

Bryan.

How are you?

The police keep a log of
all incidents involving dragons.

So, Bryan, look at here.

Accident here. Oh, here's 30 August
and 31 August.

So what happened on the 23rd?
What happened there?

Right here - one Komodo dragon
was kill one deer around
the spring water. OK.

And the last moment, 24, the police
patrol around the village here,

and saw one Komodo dragon
was killing one goat, 24th.

So two days in a row
they had dragon problems.

So the killing of a goat,

that's property and food, so that's
an economic impact to the village.
Yes, yes.

In this part of the world,

livestock often live in or around

the homes of the people
who own them.

But that risks attracting dragons
into the heart of the village.

Goats and chickens are an easy meal
for dragons,

but people have also been killed.

Children are most vulnerable,
and although attacks are rare,

police records reveal
just how cunning dragons can be.

One teacher, in 1998,
climb on a tree

and when he go down,
Komodo already waiting.

Oh, right, so the Komodo
saw the person go up the tree

and came over and sat and waited?
Yes. Smart lizard.

So what happened to that person?
Did they die?

People didn't die at the time
but two years later,

two years later he is dying. Right.

But according to the people
around here,

they believe he die
because of the bacteria.

Here in Rinca,
with the local villagers,

they quite rightly fear the dragons

because the dragons have killed
villagers

and there's also
a big economic impact

where they're regularly
taking goats and other livestock.

It is interesting, though,

that people believe things
about the dragons

that just can't be accurate.

For example, one person was bitten,
bled heavily, but he recovered.

Two years later he died.

In the intervening period
he wasn't sick,

it's not like he was wasting away,
he was healthy,

but when he died two years later,
they blamed it on his dragon bite.

Now, we don't know what
he actually died from,

but there's no way that
that was from the dragon bite.

"Infection" is a word you often hear
when people talk about dragons.

Death by infection through
a dragon bite is an idea

that has been around for 30 years.

The story goes something like this.

Komodo dragons have dirty mouths
full of lethal bacteria.

When the dragon bites, it infects
its victim with bacteria,

so if its bite doesn't kill,
the infection will.

It's a story so wonderfully horrific
it has been endlessly retold,

and today is one of the most
well-known "facts"
about Komodo dragons.

Just ask the tourists.

From what I've read,
it's the bacteria

from the mouth of the Komodo

that actually leads to
the slow death of the prey.

They've bacteria in their mouths,
they can kill large water buffalos.

It's a sort of slow death
bacterial release, you know,

so sort of very painful.

They've got mouths full of bacteria,
which sounds nasty.

Dragons are not unique
in having bacteria in their mouths.

A bite from a human could leave
the victim with a nasty infection.

But do dragons really use bacteria

as a weapon to help them
kill larger prey?

Even with its slasher bite,
the lightweight skull of a dragon

means it could face serious injury
when preying on a buffalo.

Buffalo can be as much as ten times
the weight of an average dragon.

So an additional weapon like killer
bacteria would certainly help.

It's a good story,

but Bryan just doesn't buy it.

It's been a bit of a puzzle to me

of how the whole idea
of the bacteria

being part of the predatory
behaviour of the Komodo dragon

became such gospel.

It's never actually been proven,

it's never actually been shown
that they're using bacteria.

With their natural prey item,

they're killed by
the massive blood loss.

With something like a water buffalo,
that's going to
colour our observations.

Imagine, if you will,

one of these being bitten
by a Komodo dragon and surviving,

and then hanging out
in water like this.

What do you think's going to happen?
It's going to get an infection.

Is that linked to the feeding
behaviour of the Komodo? No.

While some people believe infection
comes directly from
the mouth of the dragon,

Bryan's visit to Komodo
National Park has shown him

that there are many other
potential sources,

not least the rotten water

where the dragon's prey
loves to wallow.

But there's something about
the bacteria story

that reminds Bryan of the hunting
strategy of another type of animal.

One that he has studied
for most of his career.

The snake.

There's one particular thing
about snakes

that has fascinated Bryan
for years.

Venom.

This inland taipan has one of the
most venomous bites on the planet

and Bryan regularly
collects its venom for analysis.

Like many snakes,
it strikes quickly at its prey,

retreats,
and waits for its victim to die.

It sounds suspiciously similar to
the so-called bacteria bite

of a hunting dragon.

Bite, infect, retreat and wait.

Could the bite of a dragon,
the largest lizard in the world,

actually be venomous?

It may not be such a crazy idea.

After all, snakes and lizards
are closely related

and share a common ancestor.

Today, there are just under 4,000

species of lizard
living on the planet.

But two of these lizards stand out
from the rest

for one important reason.

Their venom.

And this is one of them -
the Mexican beaded lizard.

A bite from one of these is painful

and in severe cases can lead
to complete respiratory failure.

So if two species of lizard
use venom,

why not more?

And why not the Komodo dragon?

A hospital in the Netherlands

seems an unlikely place
to find the answer.

But Bryan has always believed
the best discoveries

come from taking a different look
at a familiar subject.

This hospital boasts
one of the best MRI scanning
departments in the world,

which is great for looking inside
the heads of human patients.

Thankfully,
that's not what Bryan is carrying.

There they are, let's have a look.

He has two pickled lizards
on loan from a local museum.

The first is the venomous
Mexican beaded lizard.

The second is the head of
a female Komodo.

Close up, the dragon's head
has some features

that makes Bryan think
an MRI scan is worthwhile.

You can see very clearly that

there's something that's running
the length of the lower jaw.

But by pressing on it, I can feel
that it's not the jaw bone -

it's soft.

That's definitely glandular
material, that's not calcium.

So the first thing we'll do is
do an MRI of the beaded

and then that'll be our control
because we know about that gland

and we've a good handle of what
it's supposed to be like
from published reports.

And then once we acquire that data,
we'll then put the Komodo dragon in

and we'll be able to compare and
contrast between the two of them.

The MRI scanner is usually used to
look inside the heads of patients,

helping diagnose illnesses
such as cancer or Alzheimer's.

This is the first time
it's being used

for something of a more
reptilian nature.

So let's see
what we're going to find.

The beaded lizard scan
has taken two hours

and the images allow Bryan

to take a fresh look at a lizard
already well-known for its venom.

So these are the results.
All right, so let's count the
compartments for the beaded lizard.

A bit further...there, stop,
stop, right there.

So, with the beaded lizard,
it's supposed to

only have one duct coming out.

That's a second duct over there.

Yeah. And then here's a third one,
here's a fourth one, five, six.

So it's got six compartments in it.

'With just the one scan
we've done right now'

we've shown that it actually has
six compartments.

So even the animals that are
well-known as being venomous,

we can learn a huge amount just by
using this kind of technology

that has never been applied
towards these kinds of animals.

Next, it's the pickled
dragon's head.

Let's see, which part do we
need to see? Lower jaw, here.

It wasn't exactly designed in mind
with the Komodo dragon

but we're learning so much
by doing it

and it's such an incredible
privilege to be able to do things

like put a Komodo dragon head
in an MRI.

I'd say this is easily the coolest
thing I've ever done in science.

So...

Oh, this is great.

It's so cool to see this.
We did it.

What started as a hunch has now been
confirmed by modern technology.

Look at the size of that
internal lumen.

The Komodo dragon does indeed
possess a venom gland.

This is our gland here.

There's a big posterior compartment

and you can see the duct
starting to emerge there.

Not only do they have this gland,

but it's a very well-developed
intricate structure,

so how did people miss this?

It's an extraordinary find that has
gone unnoticed for 100 years.

I'm just so pleased to see this -
it's incredible,

this is all my Christmases
come true,

that we've been able to show
that it's got, not just a gland,

but a very intricate gland.

All this stuff about the bacteria
is now called into question by this.

It's taken a modern medical tool

to reveal the dragon's
hidden venom gland.

But there are many types of venom.

Bryan's next task
is to find out what sort,

and to do that he must look into
the mouth of a dragon.

It's a task few would relish,

but Bryan has spent years
extracting venom from dangerous
animals across the world.

And, besides, not all dragons
are scary man-eaters.

Bryan knows a dragon with just
the right personality

to help in his research.

It lives in Bali Reptile Park

and happens to be
very, very friendly.

This is Monty,
by far my favourite animal on earth.

I've known him for years now

and we have
a bit of an understanding.

What we're going to do is

we're going to have Monty
bite down on this

and by the pressure
being transmitted along the jaw,

it deforms the jaw slightly
which squeezes the venom out.

They don't have the compressor
muscles like a snake has,

and instead the venom

just more oozes rather than being
put through like a syringe.

All right.

Perfect, yeah. Just keep it
exactly like that.

So as he bites down...

..that squeezes.

That's enough.

So we've got just a little bit
of his venom,

he's got a lot more in there
but we don't want to stress him out,

he's, of course,
such an accommodating animal.

Sorry, Monty.

Forgive me?

Yeah, I'm forgiven.

All right.

He has some venom, but Bryan
needs one final ingredient

to complete his test.

His own blood.

He adds the first sample of blood
to some water to act as a control.

The second is mixed with Monty's
venom, then left for 20 minutes.

Here are the results of
our 20-minute blood test

where in the tube without any venom,
it forms a nice normal blood clot,

while the tube with the sample
from Monty, as you can see,

it's destroyed the ability
of the blood to form the blood clot.

And that's exactly what would
happen to a prey animal,

that's why they continue to bleed,

and it's a very illustrative way

to show that there is something
in the venom that affects the blood.

This is an amazing discovery.

The ability of Monty's venom
to prevent blood clotting

isn't just a revelation
for zoologists -

it could open up new leads
in the search for new medicines.

It'll take Bryan time to analyse
the full nature of the venom

but he knows from past experience

that venoms can provide us
with new superdrugs.

We now know that a small group of
islands in the middle of Indonesia

are home to the largest
venomous animal on this planet.

It's taken science almost 100 years
to realise this.

In hindsight, the clues
were there all along.

If you look at the lower jaw
you can actually see a bulge -

that's the venom gland.

If you look in the old reptile
anatomy books, it's not in there.

But if you look at the animals,
it's a very obvious structure.

The way to think about is that
it's a combined arsenal,

that the teeth
are the primary weapon,

that's their first line of attack.

And then what the venom does
is it exaggerates the effects

of the blood pressure

so it's basically working in harmony
with the teeth.

It keeps the animal bleeding,
drops the blood pressure further

and the closer you get towards
a very low blood pressure,

the sooner you reach
unconsciousness.

It's likely that the dragon's
venomous bite

evolved long before
they reached Komodo.

We know from the fossil record

that they spent millions of years
hunting the giant animals
of Australia's past.

What in fact they had to eat
were giant forest wallabies

and wombats and weird animals that
don't exist on Komodo Island today.

So the development, the evolution of
the venom, the anti-coagulant venom

has to come from its interaction
with these sorts of prey.

So if you think of a Komodo dragon
actually attacking
and killing a large kangaroo,

venom would have been absolutely
essential because of the huge feet

and the killing force
of the strike from a kangaroo's hit.

The extraordinary journey
of the Komodo dragon has lasted
millions of years

and taken it from being
a top predator
in prehistoric Australia

to living as a castaway survivor
on a tiny group of remote islands.

They fit in here remarkably well.

It's as if they were made for
these islands.

We know now their large size

and their venomous ripping bite
evolved to tackle

large animals
that have since gone extinct,

but the dragon has survived by
adapting to new opportunities

and new prey.

For Bryan, knowing the complex
evolutionary journey

the dragon has taken
makes it all the more remarkable.

The Komodo dragon's unique in that
it's the last of the giants.

It's the only of these mega-beasts
still in existence.

So it's a snapshot back into time
when mega-fauna roamed the earth.

Modern scientific tools have at last
revealed many of the dragon's
best kept secrets.

It's a far cry from the early days
of dragon research

when it was still a creature
of myth and tall tales.

Back then, explorers were relying
entirely on their wits

and enthusiasm
simply to catch a dragon.

And how they did that
is another story.

In 1912, the astonishing news came

that a new lizard
had been discovered

that grew to the astonishing length
of 12 feet

and weighed three hundredweights.

It was discovered on one tiny little
island in the Pacific - Komodo.

In the 1950s,
a young David Attenborough

was filming a pioneering new
TV series called Zoo Quest.

Each programme was an exotic mix of
travel and natural history

with the primary aim to collect
exciting new creatures
for London Zoo.

And the Komodo dragon
was the biggest and most
dangerous animal on the list.

But finding it wouldn't be easy.

When I arrived in Java and went to
see the various authorities

that I needed to get permissions,

they'd never heard of it.
There wasn't anybody in Java

that I could discover
who knew about the Komodo dragon.

Eventually, Attenborough
travelled east of Java

and after almost a week at sea,
reached the island of Komodo.

There, he enlisted
the help of locals

to help him find the animal
they called "the land crocodile".

All that was known of it
as far as I was concerned

was that it was big,
I mean nothing more than that.

And the rest of it
was question marks.

OK, so it's the biggest land-living
lizard in the world, but why?

And why is it on that small island
and nowhere else?

'We lit a fire
and roasted some goat's flesh.'

It was clear from the start that
even the locals had little idea

about the true nature
of this animal.

'I said, "Were they dangerous
to human beings?"

'And they said, "Well, there was an
old man who was killed by a dragon,'

"but he was very old, you know,
and he'd gone out
and was sitting in the bush

"and whether he died before
the Komodo dragon got to him
or afterwards,

"we don't really know," they said.

'Now we had to set about
building a trap.'

Undeterred by the potential dangers,

Attenborough pressed ahead with
the plan to capture a dragon

for London Zoo.

'And it works.

'He put a piece of goat's flesh
inside and now all we had to do
was to wait.'

The rotting goat meat
soon did the job

of luring dragons from the forest.

'And down came the door.

'Hastily, we piled boulders on the
door so that he couldn't lift it up.

'We'd got him!'

Catching a dragon
proved relatively straightforward,

but getting the dragon
back to England would prove
an impossible task.

Unfortunately, in the end,
bureaucracy defeated us

and we weren't given a permit to
export those dragons from Indonesia,

so I'm afraid they're still there.

Attenborough wasn't the first person
to try to catch dragons.

In 1926,
an American expedition travelled
to Komodo with one big ambition.

To bring back the first dragons
from the wild.

Expedition leader William Burden

was an explorer
with matinee-idol looks

and a passion for the natural world.

Reptile expert ER Dunn
accompanied Burden and his wife

on this daring expedition.

They would spend several weeks here
shooting and trapping dragons,

and they would capture the first
ever images of dragons on film.

Only two dragons would
make it back alive to America.

The rest were mounted
as museum exhibits.

The presence of these giant
creatures from a lost world

in the metropolis of New York
caused a sensation

and ultimately inspired
the movie King Kong.

At first, zoo dragons were
little more than entertainment
for an audience.

No-one had any real idea
whether or not these animals
killed people,

and that might explain
why zoo visitors

were happy to let their children
pet a dragon's head.

Whatever the reason,
it's unlikely these early dragons

were in any fit state
to attack people.

Richard Gibson co-ordinates
the European zoos'
dragon conservation programme,

and is a curator at Chester Zoo.

We've learnt a lot
about Komodo dragon needs

in the last even 30 years,

and certainly Komodo dragons

being kept outside of their natural
range 50, 60, 70, 80 years ago

almost certainly wouldn't have been
getting the appropriate environment.

So they probably wouldn't have been
very fit and healthy.

We now know that in order for the
animal to be in good peak condition,

they have pretty extreme
environmental conditions
that we have to replicate.

Zoo dragons
have played a crucial role

in helping science
understand dragon behaviour.

Dragons were once thought
to be deaf and poorly sighted,

but zoo keepers soon realised

they had excellent eyesight
and were able to hear.

Come on. Come on, Flora. Good girl.

Work with these zoo-captive dragons

has shown us that they are,
for a lizard, an intelligent animal

that can be easily trained,

in much the same way
as we train dogs today.

Good girl.

Flora has been trained to do
simple tasks using food rewards.

So this is a brew of rather smelly
fish juice, a bit of blood,

anything that's really stinky.

So we pour this around the enclosure

and make a trail that the dragon
will follow.

Occasionally she'll find
a fish head,

a little titbit
to keep her motivated.

That encourages her
to be active and foraging.

Couple of fish heads there
to get her going.

We'd try and do some sort
of enrichment every day, really.

This will just give her new smells,
new things in her environment,

give her a reason to hunt around
and enjoy what's going on.

Although zoos have taught us
a lot about dragon behaviour,

research from wild dragons
has given zoo keepers

a better understanding
of the needs of these animals.

Looks very pleasant, doesn't it?

And that has helped keeper Matt
Swatman improve the dragon's diet.

On a daily basis they get offered
very, very small prey items.

So we give them things
like day-old chicks,

small fresh-water fish, rodents.

But obviously the bulk of
the nutritional content

regarding a dragon's diet
takes place when we do

regular carcass feeding
every six to eight weeks.

What we're doing is trying
to get the dragon to use

as much of its muscles as possible

so it really has to work
for the food.

Basically, in captivity, dragons
have the capacity to be quite lazy

and they don't have to work
very hard for their food.

So to combat that, to get them
to use their shoulders

and that pulling mechanism that in
the wild they'd use all the time...

In the wild
when you see Komodo dragons
they have beautiful muscle tone,

and in captivity we're obviously
aiming to have the same muscle tone.

So by hanging the meat up like this
we're hoping that the dragon's

going to use all those muscles
to good effect.

Trooper is a male dragon and has
been introduced as a mate for Flora,

but it seems she doesn't have
much respect for him...

yet.

Last time we put them together,
unfortunately she beat him up.

In dragon mating
it's all about the dynamic.

Generally it's a good idea
if the female has a healthy respect

or a fear of the male, really.

Breeding dragons
rarely become headline news

like pandas or gorillas.

But Flora proved to be an exception.

In fact, her journey to motherhood
was so exceptional,

some people hailed it
as a miracle.

She came to fame a few years ago

when she was the first
Komodo dragon in the world

to knowingly produce

parthenogenic offspring,
virgin conception,

eggs produced that were fertile
without any interaction with a male.

We didn't know about this
in Komodo dragons before

so my colleague and myself,
we organised for

samples from
the fertile eggs here in Chester

to be analysed genetically,

and the genetic fingerprinting
work that we did

demonstrated that the eggs had been
fertilized without a male

and it was in fact a virgin
conception or parthenogenesis.

It seems there are many aspects
of dragon behaviour

that would've gone unnoticed
without the help of zoo dragons.

And whether in zoos or in the wild,
dragons have pleased and awed crowds

for almost a century.

But there are no doubt many more
secrets they have yet to reveal

to their admiring audience.