0:00:27 > 0:00:30A tropical hill forest in East Africa.
0:00:32 > 0:00:36A place where animal communities co-exist.
0:00:38 > 0:00:42A natural balance between predators and prey.
0:00:44 > 0:00:47It's always been this way.
0:01:00 > 0:01:04But in this part of the forest, things are about to change.
0:01:10 > 0:01:13An extraordinary predator is moving in...
0:01:17 > 0:01:20..one that will ravage this forest,
0:01:20 > 0:01:23probably the most formidable killer on Earth.
0:01:24 > 0:01:29It's not an individual, but an entire army -
0:01:29 > 0:01:32an army of ants.
0:01:44 > 0:01:48This elite fighting force is a super-organism.
0:01:48 > 0:01:5220 million sisters and a few males, acting as one -
0:01:52 > 0:01:55the largest single family on the planet.
0:01:57 > 0:01:59The head of the family is a new queen.
0:01:59 > 0:02:02She'll produce the next generation
0:02:02 > 0:02:05and the army must keep her offspring alive.
0:02:05 > 0:02:08They must hunt successfully or the colony cannot grow.
0:02:11 > 0:02:15Our story is set in a parallel world to our own,
0:02:15 > 0:02:18a place where miniature monsters roam,
0:02:18 > 0:02:23violence is the law and the most numerous and powerful survive.
0:02:23 > 0:02:27This is the bug-eats-bug world of the dreaded siafu,
0:02:27 > 0:02:29the African driver ant.
0:02:47 > 0:02:52Driver ants don't have a permanent home. They're nomads.
0:02:56 > 0:03:01Every 23 days or so, they move from one part of the forest to another,
0:03:01 > 0:03:04and now they're here, somewhere,
0:03:04 > 0:03:09exploring new hunting grounds and searching for a temporary home.
0:03:09 > 0:03:12The neighbours from hell.
0:03:17 > 0:03:21Yet despite their huge numbers, you'd hardly notice they were here at all.
0:03:24 > 0:03:28They shun the light, operating down there,
0:03:28 > 0:03:32mainly amongst the dead leaves on the forest floor.
0:03:33 > 0:03:36They're swarm raiders, spreading through the forest,
0:03:36 > 0:03:40searching relentlessly for anything that moves.
0:03:42 > 0:03:47A super-predator with the mother of all appetites.
0:03:52 > 0:03:55By hunting in such an enormous group,
0:03:55 > 0:03:59the ants can bring down creatures much larger than themselves.
0:04:03 > 0:04:08When one ant finds prey, she releases a chemical alarm signal
0:04:08 > 0:04:12and within seconds hundreds of ants join the attack.
0:04:15 > 0:04:17They vary considerably in size.
0:04:19 > 0:04:22The largest is a soldier, half an inch long,
0:04:22 > 0:04:24and, like all the workers, she has no eyes.
0:04:24 > 0:04:26She's totally blind.
0:04:30 > 0:04:33She finds her way about using her two antennae,
0:04:33 > 0:04:36each covered in millions of hairs and sensory pits
0:04:36 > 0:04:39alive to smells, vibrations and touch.
0:04:43 > 0:04:48Her brain is minute. Instead, the large head is packed with muscles
0:04:48 > 0:04:52that move her gigantic, razor-sharp jaws.
0:04:58 > 0:05:03Her job is to protect the colony, for even driver ants have enemies.
0:05:05 > 0:05:08And when heavy duty cutting is required,
0:05:08 > 0:05:11her powerful jaws can slice through a victim's skin
0:05:11 > 0:05:13like a knife through butter.
0:05:15 > 0:05:19Most of the attacking and butchering is the job of the medium worker.
0:05:19 > 0:05:22She's about half the size of a soldier, also blind,
0:05:22 > 0:05:26and equipped with smaller, but tooth-studded, jaws.
0:05:26 > 0:05:29Between them, soldiers and medium workers
0:05:29 > 0:05:31can bring down almost anything,
0:05:31 > 0:05:35including creatures as large and powerful as a grasshopper.
0:05:35 > 0:05:40They rely on overwhelming numbers and sheer persistence
0:05:40 > 0:05:41to capture their prey.
0:05:44 > 0:05:47They also provide most of the transport.
0:05:53 > 0:05:58Skittering about their feet is one of the smaller workers.
0:05:58 > 0:06:02Blind like the others and just an eighth of an inch long,
0:06:02 > 0:06:03she's a general helper,
0:06:03 > 0:06:06who can do any job, from butchering, to building, to cleaning.
0:06:08 > 0:06:11All three types co-operate to carry,
0:06:11 > 0:06:14push or pull their prey along the supply lines
0:06:14 > 0:06:17from the swarm's raiding front to their next home.
0:06:20 > 0:06:25Day one in the new territory and the advance party has had some success.
0:06:26 > 0:06:29The ant army, like any army, marches on its stomach
0:06:29 > 0:06:32and the first provisions are being stashed away,
0:06:32 > 0:06:35ready for the arrival of the rest of the colony.
0:06:44 > 0:06:47Already, the first wave of workers is moving into the forest.
0:06:51 > 0:06:55They follow chemical trails that last for about a day,
0:06:55 > 0:06:57laid down by the ants ahead of them.
0:07:03 > 0:07:08Their new home is in a hollow at the base of a fallen tree.
0:07:10 > 0:07:13But the property is still only a building site.
0:07:15 > 0:07:18Construction workers enlarge the area,
0:07:18 > 0:07:22while ground workers shift debris from the main chamber.
0:07:27 > 0:07:29These tiny creatures are strong.
0:07:30 > 0:07:34Each is carrying a load that, in human terms,
0:07:34 > 0:07:37would be more than enough for an Olympic weightlifter.
0:07:37 > 0:07:41Together, they'll shift up to 80lb of soil in a couple of days.
0:07:49 > 0:07:52And they'll have to work fast,
0:07:52 > 0:07:56for the main colony is beginning to trickle in from the old nest site.
0:08:00 > 0:08:03When they enter the new chamber, some of the workers link together,
0:08:03 > 0:08:08to form long garlands of ants that join floor to ceiling.
0:08:13 > 0:08:16They start to form a protective bivouac,
0:08:16 > 0:08:20shaped like a large, round basket, inside the nest hollow.
0:08:25 > 0:08:30And the whole structure will be made entirely of living ants.
0:08:32 > 0:08:36All they are waiting for now is enough workers to fill the gaps.
0:08:39 > 0:08:41Between the old nest and the new,
0:08:41 > 0:08:46road gangs prepare the route on which the rest of the colony will trek.
0:08:51 > 0:08:52They excavate...
0:08:54 > 0:08:55..build embankments...
0:08:58 > 0:09:02..and dig tunnels, always trying to keep themselves hidden from view.
0:09:06 > 0:09:10They clear the highway of large pieces of soil
0:09:10 > 0:09:14that might slow down the traffic. And a hungry workforce must eat.
0:09:15 > 0:09:19Due to their enormous jaws, the larger ones can't feed themselves,
0:09:19 > 0:09:23so smaller ants spoon-feed them.
0:09:29 > 0:09:32But first, they must catch the food.
0:09:33 > 0:09:38The advance party has uncovered earthworms under the leaf litter.
0:09:45 > 0:09:48The ants search for weak points between segments,
0:09:48 > 0:09:52their feelers constantly tasting and touching.
0:10:00 > 0:10:02When they've found the right spot,
0:10:02 > 0:10:06their jaws close with the equivalent force of a car-crushing machine,
0:10:06 > 0:10:09and one worm becomes two.
0:10:13 > 0:10:19It's being divided into handy chunks and then hauled back to camp.
0:10:25 > 0:10:30All the meat is fast-tracked to the kitchen orderlies, deep in the nest.
0:10:30 > 0:10:34Here it's chopped, chewed and distributed to the other ants.
0:10:34 > 0:10:37And while the advance party ensures the larder is full,
0:10:37 > 0:10:42the rest of the huge family prepares to leave the old nest site.
0:10:45 > 0:10:48JUNGLE BIRDSONG
0:10:48 > 0:10:52It's day two and the mass evacuation is underway.
0:10:56 > 0:10:59The ants march along well-worn tracks,
0:10:59 > 0:11:03originally foraging trails between the old nest and swarm front,
0:11:03 > 0:11:08but now the main roads along which queen and colony will pass.
0:11:10 > 0:11:14Their trek is about the length of two football pitches laid end to end.
0:11:14 > 0:11:17They're not travelling empty-handed.
0:11:17 > 0:11:21Each ant carries a larva or a pupa hung below her body -
0:11:21 > 0:11:25the equivalent of us running a marathon carrying a sack of potatoes
0:11:25 > 0:11:27and not stopping for a rest.
0:11:31 > 0:11:35The entire emigration can take up to three days.
0:11:40 > 0:11:44It seems chaotic, but every ant in this extraordinary melee
0:11:44 > 0:11:46knows exactly what she's doing.
0:11:54 > 0:11:58Giant soldiers, with their massive jaws, line the route,
0:11:58 > 0:12:02so workers with their precious cargo travel safely along a living avenue.
0:12:09 > 0:12:13They're passing at a rate of 250,000 ants an hour.
0:12:17 > 0:12:21Some unwittingly carry infiltrators -
0:12:21 > 0:12:24even tiny ants are host to even tinier mites.
0:12:32 > 0:12:34The invading army is building in numbers.
0:12:50 > 0:12:54Travelling with her subjects is the queen.
0:12:54 > 0:12:59At two inches long, she is the largest ant in the world.
0:13:02 > 0:13:04And she's a new queen.
0:13:04 > 0:13:08When her mother's colony grew too large and divided,
0:13:08 > 0:13:12half the workers switched their allegiance and now accompany her
0:13:12 > 0:13:14on her first emigration.
0:13:23 > 0:13:26Her enormous bulk has been coaxed along the trail
0:13:26 > 0:13:30and now she takes her place at the heart of the nest.
0:13:42 > 0:13:47The queen is in her palace - and what a palace it's become.
0:13:47 > 0:13:51It's a living bivouac,
0:13:51 > 0:13:55a nest made entirely of ants.
0:14:01 > 0:14:05All its internal walls are made of ants, all its corridors
0:14:05 > 0:14:09and chambers constructed of living bricks.
0:14:11 > 0:14:15And when they're all assembled in their new stronghold,
0:14:15 > 0:14:19they form one of the largest concentrations of ants on Earth.
0:14:23 > 0:14:27Protected by these living walls are the nurseries,
0:14:27 > 0:14:31where wave after wave of brood carriers deliver their load.
0:14:37 > 0:14:40By the end of day three, they're packed with larvae and pupae.
0:14:51 > 0:14:56In the royal chamber, the queen has yet to restart her normal duties.
0:14:56 > 0:15:00Before her journey, she stopped egg production, in order to slim down
0:15:00 > 0:15:03and make travelling easier.
0:15:05 > 0:15:07Now, like a virgin queen,
0:15:07 > 0:15:11she produces a special scent that attracts winged male ants
0:15:11 > 0:15:14who fly in from other nests.
0:15:16 > 0:15:20The male is also enormous, on a similar scale to the queen.
0:15:25 > 0:15:29The scents she produces are irresistible.
0:15:32 > 0:15:36Just a few molecules will grab a male's attention.
0:15:39 > 0:15:42He searches for a way into the nest.
0:15:46 > 0:15:49But a guard patrol has found him
0:15:49 > 0:15:54and at first the other ants see him as food. He's in mortal danger.
0:15:59 > 0:16:03The army smothers him as if he were prey,
0:16:03 > 0:16:05but their intentions falter.
0:16:13 > 0:16:18He produces scents to demonstrate his fitness to be consort.
0:16:18 > 0:16:21If he passes muster, he'll be accepted. If he doesn't,
0:16:21 > 0:16:24he'll be for the chop.
0:16:24 > 0:16:28They try to clip his wings so he'll fit through the nest entrance,
0:16:28 > 0:16:32but he cooperates - using spikes at the end of his abdomen,
0:16:32 > 0:16:34he pulls one off himself.
0:16:40 > 0:16:44Nothing is wasted. Even a wing has some nutritional value.
0:16:46 > 0:16:50The rest of the workers take him into the nest.
0:16:50 > 0:16:53He has their support, at least for the time being.
0:16:53 > 0:16:56He's on probation.
0:16:57 > 0:17:01Until he actually mates with the queen, he could still be attacked.
0:17:02 > 0:17:04Another wing is removed.
0:17:09 > 0:17:13He'll soon be presentable for his audience with the queen.
0:17:18 > 0:17:21It's day five in the new territory.
0:17:21 > 0:17:23There's no nuptial flight.
0:17:23 > 0:17:27Instead, the queen's new consort is guided directly to the royal chamber.
0:17:27 > 0:17:32He's not the first consort to the queen and probably won't be the last.
0:17:32 > 0:17:37Driver ant queens are, for ants, unusually promiscuous.
0:17:37 > 0:17:41He'll be one of many suitors she'll entertain during her lifetime.
0:17:43 > 0:17:48His job done, he retires from the royal chamber and dies.
0:17:48 > 0:17:50A short but productive life,
0:17:50 > 0:17:55for he'll father several million new ants with hungry mouths.
0:17:55 > 0:17:59The pressure is building for the colony to provide more and more food.
0:18:02 > 0:18:05The raiders head west
0:18:05 > 0:18:08and they don't stay on the ground.
0:18:08 > 0:18:12There's plenty to eat up here in the trees.
0:18:14 > 0:18:18A male hornbill cements his family into a hole in the trunk,
0:18:18 > 0:18:21leaving a small gap through which he passes food.
0:18:21 > 0:18:25It'll keep out tree snakes, but not ants.
0:18:28 > 0:18:32Driver ants would strip the flesh from the female hornbill and chicks
0:18:32 > 0:18:36in a matter of hours. He's understandably nervous.
0:18:38 > 0:18:43The ants are as adept at climbing as they are at running.
0:18:58 > 0:19:01As long as the forest is dark and humid,
0:19:01 > 0:19:05they seem as at home in the trees as on the ground.
0:19:10 > 0:19:13The army is close.
0:19:19 > 0:19:20But not close enough.
0:19:22 > 0:19:27If the ants climb too high and are too spread out,
0:19:27 > 0:19:30there'll be too few to overwhelm prey.
0:19:30 > 0:19:34This nest is out of reach.
0:19:34 > 0:19:38The family is safe.
0:19:41 > 0:19:44But there's plenty more prey up here.
0:19:45 > 0:19:49Slugs are fair game for driver ants.
0:19:49 > 0:19:51They don't run away.
0:19:52 > 0:19:55The first ant makes contact.
0:20:02 > 0:20:04And then another.
0:20:04 > 0:20:07Others come running.
0:20:07 > 0:20:10The slug tries to sit out the attack.
0:20:10 > 0:20:13There are so many ants.
0:20:16 > 0:20:21The victim uses the only escape route left to it.
0:20:23 > 0:20:26The ants fall too.
0:20:26 > 0:20:30They often use this unconventional way to get down from the trees.
0:20:30 > 0:20:35But the unfortunate slug has fallen from the frying pan into the fire.
0:20:38 > 0:20:43An awful lot of ants are milling about down here.
0:20:59 > 0:21:02They smother their prey.
0:21:03 > 0:21:08But the slug has a trick up its sleeve.
0:21:08 > 0:21:11It may be slow, but it's well protected.
0:21:20 > 0:21:24Its entire body is covered in a thick and noxious slime.
0:21:24 > 0:21:27It's so glutinous that once their jaws are in
0:21:27 > 0:21:30they can't get them out.
0:21:30 > 0:21:34Other ants seem to give a helping hand.
0:21:55 > 0:21:57But this one is firmly stuck.
0:22:01 > 0:22:06Try as she might, she just can't get away.
0:22:19 > 0:22:23For some, it's not just their jaws that are trapped.
0:22:45 > 0:22:48She's almost free.
0:22:55 > 0:22:58Then something remarkable happens.
0:22:58 > 0:23:02Some of the workers begin to bring particles of soil
0:23:02 > 0:23:05and place them on the slug. In this way,
0:23:05 > 0:23:09the slime is soaked up like ink on blotting paper.
0:23:12 > 0:23:17Gradually, the slug disappears under a writhing mass of earth and ants.
0:23:28 > 0:23:33With its protective coat neutralised, the ants attack the slug underneath.
0:23:36 > 0:23:39Slowly, the victim is sliced up.
0:23:51 > 0:23:55Piece by piece, small chunks are pulled away.
0:24:01 > 0:24:03As the flesh is removed,
0:24:03 > 0:24:07the butchers switch roles and become transporters.
0:24:07 > 0:24:11They carry the food along the foraging trails back to camp.
0:24:11 > 0:24:14The larvae will be fed tonight.
0:24:17 > 0:24:22By day ten, the queen resumes her primary role as super-mother,
0:24:22 > 0:24:24the ultimate egg-laying machine.
0:24:26 > 0:24:30Food is served to her at one end...
0:24:30 > 0:24:34and eggs appear at the other.
0:24:34 > 0:24:39She produces a staggering two million eggs a month.
0:24:42 > 0:24:45The palace staff bustles around her,
0:24:45 > 0:24:49collecting packages of eggs, grooming her constantly.
0:24:49 > 0:24:53She's the colony's most valuable asset, a link to the future.
0:25:03 > 0:25:08The ants around her are quite prepared to die for her,
0:25:08 > 0:25:12not because of any love for a mother, but to protect the blueprint
0:25:12 > 0:25:15that makes them what they are and what they do.
0:25:18 > 0:25:21They pick up clumps of the precious eggs
0:25:21 > 0:25:24and gently carry them to the nursery.
0:25:24 > 0:25:28The already huge ant population is increasing exponentially
0:25:28 > 0:25:32and the demand for food is growing astronomically.
0:25:32 > 0:25:35There's a need for a greater than ever increase in rations.
0:25:39 > 0:25:42Having raided to the north and west
0:25:42 > 0:25:46and eliminated every living thing that slithers or crawls,
0:25:46 > 0:25:48the columns head south.
0:25:54 > 0:25:58The raid takes them into a wet and swampy area.
0:25:58 > 0:26:00This is no deterrent.
0:26:00 > 0:26:04Driver ants are proficient at crossing difficult terrain.
0:26:11 > 0:26:15But a river is something even they can't manage.
0:26:17 > 0:26:20They've reached the southern edge of their territory
0:26:20 > 0:26:24and water and ants don't mix.
0:26:40 > 0:26:44They head back inland and straight into another barrier.
0:26:47 > 0:26:50But a shallow pond is no obstacle.
0:26:50 > 0:26:54In order to cross, the ants simply build a bridge.
0:27:10 > 0:27:15It's made out of leaves and the ants themselves -
0:27:15 > 0:27:17a living bridge.
0:27:30 > 0:27:36The swarm raiders stream across the pond, but the raid is failing.
0:27:36 > 0:27:38They're carrying little food.
0:27:38 > 0:27:40The ants retreat.
0:27:47 > 0:27:50But fortunes change.
0:27:50 > 0:27:55The raiding party has flushed out what seems an unassailable quarry.
0:28:03 > 0:28:07Freshwater crabs are common in the forest
0:28:07 > 0:28:09but a surprising targets for ants.
0:28:14 > 0:28:17At first, the raiders do what's natural,
0:28:17 > 0:28:22swarming over their intended victim. But there's no way their tiny jaws
0:28:22 > 0:28:25will pierce the crab's thick outer skeleton.
0:28:25 > 0:28:29Instinctively, they probe for its weak points.
0:28:29 > 0:28:33One group examines the legs and claws for a way in.
0:28:33 > 0:28:35This has its dangers.
0:28:35 > 0:28:41They search for the vulnerable joints and hack their way into the leg.
0:28:41 > 0:28:44Using knife-like mandibles,
0:28:44 > 0:28:46they slice away the soft tissue
0:28:46 > 0:28:50and as the joint is ripped and the tear widened,
0:28:50 > 0:28:54the smaller workers are able to climb into the crab's legs
0:28:54 > 0:28:56to reach the muscles inside.
0:29:15 > 0:29:18Another group checks out the mouth.
0:29:23 > 0:29:25They seem to work together.
0:29:25 > 0:29:30The larger soldiers prise open the mouth parts so smaller workers can
0:29:30 > 0:29:34squeeze through and attack the softer tissues behind.
0:29:34 > 0:29:37The ants are dwarfed by the crab,
0:29:37 > 0:29:41yet with so many attacking at one time, even a fully armoured crab
0:29:41 > 0:29:44doesn't stand a chance.
0:29:45 > 0:29:48Ants eat from inside out.
0:29:51 > 0:29:53By day 22,
0:29:53 > 0:29:57raiding parties have quartered almost every part of their territory
0:29:57 > 0:30:02and in the brood chambers there are now four million more mouths to feed.
0:30:02 > 0:30:05The larvae are voracious
0:30:05 > 0:30:09and the raiders barely keep pace with their demand for food.
0:30:25 > 0:30:28The family is at crisis point.
0:30:38 > 0:30:41There's just one part of the forest left to explore
0:30:41 > 0:30:46and here they stumble upon an unexpected prize,
0:30:46 > 0:30:50a mound made by forest termites.
0:30:52 > 0:30:57Termites have a permanent home, more a fortress than a nest.
0:30:57 > 0:31:00Inside live two million residents.
0:31:00 > 0:31:05Now winged termites are leaving the safety of the mound.
0:31:05 > 0:31:07They're the future kings and queens
0:31:07 > 0:31:10and they do go on a nuptial flight.
0:31:10 > 0:31:14Late in the day, they emerge from the nest.
0:31:20 > 0:31:23Just a few fail to fly very far.
0:31:24 > 0:31:27They'll be easy pickings.
0:31:30 > 0:31:35The reign of this young pretender will be cut short, as will its life.
0:31:39 > 0:31:44The ants swarm over any termite that falls short.
0:31:48 > 0:31:51The work detail
0:31:51 > 0:31:55tries to control and snip off the unmanageable wings.
0:31:57 > 0:32:01For a tiny ant, it's like wrestling with a gigantic sail.
0:32:05 > 0:32:10Others anchor down their victim by holding onto its legs.
0:32:18 > 0:32:22As the hauliers keep pulling and pushing, the butchers keep slicing.
0:32:29 > 0:32:33The raiding party heads home with an almost headless victim,
0:32:33 > 0:32:35but their haul of a few termites
0:32:35 > 0:32:39is far less than the colony needs.
0:32:44 > 0:32:47As the evening draws in and the temperature drops,
0:32:47 > 0:32:50the ants become lethargic.
0:32:50 > 0:32:54They head back to their nest for the night,
0:32:54 > 0:32:58but in returning home they miss out on the biggest feast there's been
0:32:58 > 0:33:02in this part of the forest for a long time.
0:33:08 > 0:33:13The main exodus of winged termites is this night.
0:33:13 > 0:33:16Tens of thousands emerge at the same time.
0:33:18 > 0:33:22This would be such a glut of ant food
0:33:22 > 0:33:25it would satisfy all 20 million for several days.
0:33:25 > 0:33:27But the ants are not here.
0:33:27 > 0:33:31The termites are on the wing. The feast is flying away.
0:33:31 > 0:33:35And the ant brood is demanding increasingly more food.
0:33:35 > 0:33:40If none is forthcoming, the new generation could be put on hold.
0:33:40 > 0:33:43The next 24 hours are critical.
0:33:54 > 0:33:56A new day
0:33:56 > 0:33:59and for the ants a renewed challenge.
0:34:05 > 0:34:08This has been their home for 23 days.
0:34:08 > 0:34:12Successful hunting means their forest larder is almost bare.
0:34:14 > 0:34:17The entire army is mobilising.
0:34:25 > 0:34:29The raiding parties head out to the last place they'd found food,
0:34:29 > 0:34:32where they had pinned down the few winged termites.
0:34:51 > 0:34:53The bearing they've taken
0:34:53 > 0:34:57is leading them straight towards the termite mound itself.
0:35:03 > 0:35:06Ants and termites have been adversaries
0:35:06 > 0:35:08for over 100 million years.
0:35:08 > 0:35:12Now their armies of today are on a collision course.
0:35:12 > 0:35:14But without any physical contact,
0:35:14 > 0:35:18the blind army is as unaware of the termites ahead
0:35:18 > 0:35:21as the termites are of the approaching ants.
0:35:21 > 0:35:25They begin to swarm over the outside of the termite towers
0:35:25 > 0:35:30that for the moment appear to them to be just mounds of dried mud.
0:35:47 > 0:35:49Guards are posted
0:35:49 > 0:35:54while others explore every crevice for any sign of food.
0:35:54 > 0:35:56First contact.
0:35:56 > 0:35:58The ants know there's something here
0:35:58 > 0:36:02and change direction towards the alarm signal. They mass around,
0:36:02 > 0:36:06the guards alert for any unpleasant surprises.
0:36:09 > 0:36:12This is unknown territory.
0:36:12 > 0:36:15Anything could be lying in wait down there.
0:36:18 > 0:36:21A worker gingerly explores the gaping hole
0:36:21 > 0:36:25and a scouting party lays a scent trail for others to follow.
0:36:27 > 0:36:30Activity increases.
0:36:30 > 0:36:33An assault is on.
0:36:41 > 0:36:47Other ants have found the termites' foraging tunnels and scramble inside.
0:36:47 > 0:36:52The tunnels are narrow and not like the open spaces driver ants prefer.
0:36:57 > 0:37:00Termite soldiers with enormous jaws and heads
0:37:00 > 0:37:03prepare to check the incursion.
0:37:08 > 0:37:12A soldier termite confronts the invaders with a threat display,
0:37:12 > 0:37:16but it's not going to impress a driver ant.
0:37:19 > 0:37:22The ants penetrate deep into the nest
0:37:22 > 0:37:26and the residents intensify their warning.
0:37:31 > 0:37:34First blood is to the termites.
0:37:37 > 0:37:41But the tunnel guards are in danger of being overrun.
0:37:48 > 0:37:51The ants break through the first line of defence.
0:38:09 > 0:38:12Another wave of ants advances unchallenged.
0:38:17 > 0:38:19But the attack is not going to plan.
0:38:22 > 0:38:26In the tunnels, the ants become embroiled in one-to-one duels.
0:39:15 > 0:39:19The jaw-to-jaw combat is at stalemate.
0:39:19 > 0:39:22Ants and termites seem locked in a lethal embrace.
0:39:30 > 0:39:33The adversaries are well matched.
0:39:42 > 0:39:44The ants are pulling out.
0:39:48 > 0:39:52Their army will have to look elsewhere.
0:39:56 > 0:39:59But not all are going home.
0:40:08 > 0:40:11Those who can move out do so.
0:40:14 > 0:40:17The termite mound has defeated them.
0:40:17 > 0:40:21They must find food in another part of the forest.
0:40:35 > 0:40:38For the ant army, a big change is inevitable.
0:40:43 > 0:40:46The queen makes ready for a journey.
0:40:50 > 0:40:54The lower ranks gather up all the larvae in the nursery
0:40:54 > 0:40:56and move them to the nest entrance.
0:41:05 > 0:41:09They've depleted the food supply in the vicinity of their nest
0:41:09 > 0:41:11and must leave.
0:41:11 > 0:41:14They've outstayed their welcome.
0:41:25 > 0:41:29Swarm raiding parties have located a concentration of food
0:41:29 > 0:41:31200 metres further on,
0:41:31 > 0:41:36so the entire colony must relocate in order to exploit it.
0:41:36 > 0:41:40They've wreaked havoc here,
0:41:40 > 0:41:44so they're moving on to terrorise another part of the forest.
0:41:45 > 0:41:50Yet the ants are important to the forest's well-being.
0:41:50 > 0:41:53The culling of bugs and slugs
0:41:53 > 0:41:57ensures that no one species dominates.
0:41:57 > 0:42:01Driver ants help maintain the huge range of plants and animals.
0:42:01 > 0:42:07Despite all the killing, driver ants are an essential part of forest life,
0:42:07 > 0:42:11in many ways the good guys after all.