All language subtitles for Natural.World.S24E13.2006.Ant.Attack.720p.HDTV.x264.AAC.MVGroup.org.en

A tropical hill forest
in East Africa.

A place where
animal communities co-exist.

A natural balance
between predators and prey.

It's always been this way.

But in this part of the forest,
things are about to change.

An extraordinary predator
is moving in...

..one that will ravage this forest,

probably the most formidable killer
on Earth.

It's not an individual,
but an entire army -

an army of ants.

This elite fighting force
is a super-organism.

20 million sisters
and a few males, acting as one -

the largest single family
on the planet.

The head of the family
is a new queen.

She'll produce the next generation

and the army
must keep her offspring alive.

They must hunt successfully
or the colony cannot grow.

Our story is set
in a parallel world to our own,

a place where
miniature monsters roam,

violence is the law and the
most numerous and powerful survive.

This is the bug-eats-bug world
of the dreaded siafu,

the African driver ant.

Driver ants don't have
a permanent home. They're nomads.

Every 23 days or so, they move from
one part of the forest to another,

and now they're here, somewhere,

exploring new hunting grounds
and searching for a temporary home.

The neighbours from hell.

Yet despite their huge numbers, you'd
hardly notice they were here at all.

They shun the light,
operating down there,

mainly amongst the dead leaves
on the forest floor.

They're swarm raiders,
spreading through the forest,

searching relentlessly
for anything that moves.

A super-predator
with the mother of all appetites.

By hunting in such an enormous group,

the ants can bring down creatures
much larger than themselves.

When one ant finds prey,
she releases a chemical alarm signal

and within seconds
hundreds of ants join the attack.

They vary considerably in size.

The largest is a soldier,
half an inch long,

and, like all the workers,
she has no eyes.

She's totally blind.

She finds her way about
using her two antennae,

each covered in millions
of hairs and sensory pits

alive to smells,
vibrations and touch.

Her brain is minute. Instead, the
large head is packed with muscles

that move her gigantic,
razor-sharp jaws.

Her job is to protect the colony,
for even driver ants have enemies.

And when heavy duty cutting
is required,

her powerful jaws can slice through
a victim's skin

like a knife through butter.

Most of the attacking and butchering
is the job of the medium worker.

She's about half the size
of a soldier, also blind,

and equipped with smaller,
but tooth-studded, jaws.

Between them, soldiers
and medium workers

can bring down almost anything,

including creatures as large
and powerful as a grasshopper.

They rely on overwhelming numbers
and sheer persistence

to capture their prey.

They also provide
most of the transport.

Skittering about their feet
is one of the smaller workers.

Blind like the others
and just an eighth of an inch long,

she's a general helper,

who can do any job, from butchering,
to building, to cleaning.

All three types co-operate to carry,

push or pull their prey
along the supply lines

from the swarm's raiding front
to their next home.

Day one in the new territory and the
advance party has had some success.

The ant army, like any army,
marches on its stomach

and the first provisions
are being stashed away,

ready for the arrival
of the rest of the colony.

Already, the first wave of workers
is moving into the forest.

They follow chemical trails
that last for about a day,

laid down by the ants ahead of them.

Their new home is in a hollow
at the base of a fallen tree.

But the property is still only
a building site.

Construction workers
enlarge the area,

while ground workers shift debris
from the main chamber.

These tiny creatures are strong.

Each is carrying a load that,
in human terms,

would be more than enough
for an Olympic weightlifter.

Together, they'll shift up to 80lb
of soil in a couple of days.

And they'll have to work fast,

for the main colony is beginning
to trickle in from the old nest site.

When they enter the new chamber,
some of the workers link together,

to form long garlands of ants
that join floor to ceiling.

They start to form
a protective bivouac,

shaped like a large, round basket,
inside the nest hollow.

And the whole structure will
be made entirely of living ants.

All they are waiting for now
is enough workers to fill the gaps.

Between the old nest and the new,

road gangs prepare the route on which
the rest of the colony will trek.

They excavate...

..build embankments...

..and dig tunnels, always trying
to keep themselves hidden from view.

They clear the highway
of large pieces of soil

that might slow down the traffic.
And a hungry workforce must eat.

Due to their enormous jaws, the
larger ones can't feed themselves,

so smaller ants spoon-feed them.

But first, they must catch the food.

The advance party has uncovered
earthworms under the leaf litter.

The ants search for weak points
between segments,

their feelers constantly
tasting and touching.

When they've found the right spot,

their jaws close with the equivalent
force of a car-crushing machine,

and one worm becomes two.

It's being divided into handy chunks
and then hauled back to camp.

All the meat is fast-tracked to the
kitchen orderlies, deep in the nest.

Here it's chopped, chewed
and distributed to the other ants.

And while the advance party
ensures the larder is full,

the rest of the huge family
prepares to leave the old nest site.

JUNGLE BIRDSONG

It's day two
and the mass evacuation is underway.

The ants march along
well-worn tracks,

originally foraging trails between
the old nest and swarm front,

but now the main roads along which
queen and colony will pass.

Their trek is about the length of
two football pitches laid end to end.

They're not travelling empty-handed.

Each ant carries a larva
or a pupa hung below her body -

the equivalent of us running a
marathon carrying a sack of potatoes

and not stopping for a rest.

The entire emigration
can take up to three days.

It seems chaotic, but every ant
in this extraordinary melee

knows exactly what she's doing.

Giant soldiers, with their
massive jaws, line the route,

so workers with their precious cargo
travel safely along a living avenue.

They're passing at a rate
of 250,000 ants an hour.

Some unwittingly carry infiltrators -

even tiny ants are host
to even tinier mites.

The invading army
is building in numbers.

Travelling with her subjects
is the queen.

At two inches long, she is
the largest ant in the world.

And she's a new queen.

When her mother's colony
grew too large and divided,

half the workers switched their
allegiance and now accompany her

on her first emigration.

Her enormous bulk has been coaxed
along the trail

and now she takes her place
at the heart of the nest.

The queen is in her palace -
and what a palace it's become.

It's a living bivouac,

a nest made entirely of ants.

All its internal walls are made
of ants, all its corridors

and chambers constructed
of living bricks.

And when they're all assembled
in their new stronghold,

they form one of the largest
concentrations of ants on Earth.

Protected by these living walls
are the nurseries,

where wave after wave of brood
carriers deliver their load.

By the end of day three,
they're packed with larvae and pupae.

In the royal chamber, the queen has
yet to restart her normal duties.

Before her journey, she stopped egg
production, in order to slim down

and make travelling easier.

Now, like a virgin queen,

she produces a special scent
that attracts winged male ants

who fly in from other nests.

The male is also enormous,
on a similar scale to the queen.

The scents she produces
are irresistible.

Just a few molecules
will grab a male's attention.

He searches for a way into the nest.

But a guard patrol has found him

and at first the other ants see him
as food. He's in mortal danger.

The army smothers him
as if he were prey,

but their intentions falter.

He produces scents to demonstrate
his fitness to be consort.

If he passes muster,
he'll be accepted. If he doesn't,

he'll be for the chop.

They try to clip his wings so he'll
fit through the nest entrance,

but he cooperates - using spikes
at the end of his abdomen,

he pulls one off himself.

Nothing is wasted. Even a wing has
some nutritional value.

The rest of the workers
take him into the nest.

He has their support,
at least for the time being.

He's on probation.

Until he actually mates with the
queen, he could still be attacked.

Another wing is removed.

He'll soon be presentable
for his audience with the queen.

It's day five in the new territory.

There's no nuptial flight.

Instead, the queen's new consort is
guided directly to the royal chamber.

He's not the first consort to the
queen and probably won't be the last.

Driver ant queens are, for ants,
unusually promiscuous.

He'll be one of many suitors she'll
entertain during her lifetime.

His job done, he retires
from the royal chamber and dies.

A short but productive life,

for he'll father several million
new ants with hungry mouths.

The pressure is building for the
colony to provide more and more food.

The raiders head west

and they don't stay on the ground.

There's plenty to eat up here
in the trees.

A male hornbill cements his family
into a hole in the trunk,

leaving a small gap
through which he passes food.

It'll keep out tree snakes,
but not ants.

Driver ants would strip the flesh
from the female hornbill and chicks

in a matter of hours.
He's understandably nervous.

The ants are as adept at climbing
as they are at running.

As long as the forest is dark
and humid,

they seem as at home in the trees
as on the ground.

The army is close.

But not close enough.

If the ants climb too high
and are too spread out,

there'll be too few
to overwhelm prey.

This nest is out of reach.

The family is safe.

But there's plenty more prey up here.

Slugs are fair game for driver ants.

They don't run away.

The first ant makes contact.

And then another.

Others come running.

The slug tries to sit out the attack.

There are so many ants.

The victim uses the only escape route
left to it.

The ants fall too.

They often use this unconventional
way to get down from the trees.

But the unfortunate slug has fallen
from the frying pan into the fire.

An awful lot of ants are milling
about down here.

They smother their prey.

But the slug has a trick
up its sleeve.

It may be slow,
but it's well protected.

Its entire body is covered
in a thick and noxious slime.

It's so glutinous
that once their jaws are in

they can't get them out.

Other ants seem to give
a helping hand.

But this one is firmly stuck.

Try as she might,
she just can't get away.

For some, it's not just their jaws
that are trapped.

She's almost free.

Then something remarkable happens.

Some of the workers begin to bring
particles of soil

and place them on the slug.
In this way,

the slime is soaked up
like ink on blotting paper.

Gradually, the slug disappears under
a writhing mass of earth and ants.

With its protective coat neutralised,
the ants attack the slug underneath.

Slowly, the victim is sliced up.

Piece by piece,
small chunks are pulled away.

As the flesh is removed,

the butchers switch roles
and become transporters.

They carry the food along
the foraging trails back to camp.

The larvae will be fed tonight.

By day ten, the queen resumes
her primary role as super-mother,

the ultimate egg-laying machine.

Food is served to her at one end...

and eggs appear at the other.

She produces a staggering
two million eggs a month.

The palace staff bustles around her,

collecting packages of eggs,
grooming her constantly.

She's the colony's most valuable
asset, a link to the future.

The ants around her are quite
prepared to die for her,

not because of any love for a mother,
but to protect the blueprint

that makes them what they are
and what they do.

They pick up clumps
of the precious eggs

and gently carry them to the nursery.

The already huge ant population is
increasing exponentially

and the demand for food is growing
astronomically.

There's a need for a greater than
ever increase in rations.

Having raided to the north and west

and eliminated every living thing
that slithers or crawls,

the columns head south.

The raid takes them into
a wet and swampy area.

This is no deterrent.

Driver ants are proficient
at crossing difficult terrain.

But a river is something
even they can't manage.

They've reached the southern edge of
their territory

and water and ants don't mix.

They head back inland
and straight into another barrier.

But a shallow pond is no obstacle.

In order to cross,
the ants simply build a bridge.

It's made out of leaves
and the ants themselves -

a living bridge.

The swarm raiders stream across
the pond, but the raid is failing.

They're carrying little food.

The ants retreat.

But fortunes change.

The raiding party has flushed out
what seems an unassailable quarry.

Freshwater crabs
are common in the forest

but a surprising targets for ants.

At first, the raiders do
what's natural,

swarming over their intended victim.
But there's no way their tiny jaws

will pierce the crab's
thick outer skeleton.

Instinctively, they probe
for its weak points.

One group examines the legs and claws
for a way in.

This has its dangers.

They search for the vulnerable joints
and hack their way into the leg.

Using knife-like mandibles,

they slice away the soft tissue

and as the joint is ripped
and the tear widened,

the smaller workers are able to climb
into the crab's legs

to reach the muscles inside.

Another group checks out the mouth.

They seem to work together.

The larger soldiers prise open the
mouth parts so smaller workers can

squeeze through and attack
the softer tissues behind.

The ants are dwarfed by the crab,

yet with so many attacking at one
time, even a fully armoured crab

doesn't stand a chance.

Ants eat from inside out.

By day 22,

raiding parties have quartered
almost every part of their territory

and in the brood chambers there are
now four million more mouths to feed.

The larvae are voracious

and the raiders barely keep pace
with their demand for food.

The family is at crisis point.

There's just one part of the forest
left to explore

and here they stumble upon
an unexpected prize,

a mound made by forest termites.

Termites have a permanent home,
more a fortress than a nest.

Inside live two million residents.

Now winged termites are leaving
the safety of the mound.

They're the future kings and queens

and they do go on a nuptial flight.

Late in the day,
they emerge from the nest.

Just a few fail to fly very far.

They'll be easy pickings.

The reign of this young pretender
will be cut short, as will its life.

The ants swarm over any termite
that falls short.

The work detail

tries to control and snip off
the unmanageable wings.

For a tiny ant, it's like wrestling
with a gigantic sail.

Others anchor down their victim
by holding onto its legs.

As the hauliers keep pulling and
pushing, the butchers keep slicing.

The raiding party heads home
with an almost headless victim,

but their haul of a few termites

is far less than the colony needs.

As the evening draws in
and the temperature drops,

the ants become lethargic.

They head back to their nest
for the night,

but in returning home they miss out
on the biggest feast there's been

in this part of the forest
for a long time.

The main exodus of winged termites
is this night.

Tens of thousands emerge
at the same time.

This would be such a glut of ant food

it would satisfy all 20 million
for several days.

But the ants are not here.

The termites are on the wing.
The feast is flying away.

And the ant brood is demanding
increasingly more food.

If none is forthcoming, the new
generation could be put on hold.

The next 24 hours are critical.

A new day

and for the ants a renewed challenge.

This has been their home for 23 days.

Successful hunting means
their forest larder is almost bare.

The entire army is mobilising.

The raiding parties head out
to the last place they'd found food,

where they had pinned down
the few winged termites.

The bearing they've taken

is leading them straight towards
the termite mound itself.

Ants and termites have been
adversaries

for over 100 million years.

Now their armies of today are
on a collision course.

But without any physical contact,

the blind army is as unaware
of the termites ahead

as the termites are
of the approaching ants.

They begin to swarm over the outside
of the termite towers

that for the moment appear to them
to be just mounds of dried mud.

Guards are posted

while others explore every crevice
for any sign of food.

First contact.

The ants know there's something here

and change direction towards
the alarm signal. They mass around,

the guards alert
for any unpleasant surprises.

This is unknown territory.

Anything could be lying in wait
down there.

A worker gingerly explores
the gaping hole

and a scouting party lays a scent
trail for others to follow.

Activity increases.

An assault is on.

Other ants have found the termites'
foraging tunnels and scramble inside.

The tunnels are narrow and not like
the open spaces driver ants prefer.

Termite soldiers with enormous jaws
and heads

prepare to check the incursion.

A soldier termite confronts
the invaders with a threat display,

but it's not going to impress
a driver ant.

The ants penetrate deep into the nest

and the residents intensify
their warning.

First blood is to the termites.

But the tunnel guards
are in danger of being overrun.

The ants break through
the first line of defence.

Another wave of ants advances
unchallenged.

But the attack is not going to plan.

In the tunnels, the ants become
embroiled in one-to-one duels.

The jaw-to-jaw combat
is at stalemate.

Ants and termites seem
locked in a lethal embrace.

The adversaries are well matched.

The ants are pulling out.

Their army will have to look
elsewhere.

But not all are going home.

Those who can move out do so.

The termite mound has defeated them.

They must find food
in another part of the forest.

For the ant army,
a big change is inevitable.

The queen makes ready for a journey.

The lower ranks gather up
all the larvae in the nursery

and move them to the nest entrance.

They've depleted the food supply
in the vicinity of their nest

and must leave.

They've outstayed their welcome.

Swarm raiding parties have located
a concentration of food

200 metres further on,

so the entire colony must relocate
in order to exploit it.

They've wreaked havoc here,

so they're moving on to terrorise
another part of the forest.

Yet the ants are important
to the forest's well-being.

The culling of bugs and slugs

ensures that no one species
dominates.

Driver ants help maintain
the huge range of plants and animals.

Despite all the killing, driver ants
are an essential part of forest life,

in many ways
the good guys after all.