Original subtitles

(SOFT MUSIC) (RAINFOREST AMBIENCE)

The rainforest.

The busiest and most diverse habitat on Earth.

(BIRD TWEETS)

Home to half of all plant and animal species,

living cheek by jowl...

(LEOPARD GROWLS)

...in tightly packed communities.

Here, in the Americas,

it's hot, humid,

and unforgiving.

(THUNDER)

Up to 2 metres of rain falls each year.

But for a few, short months, the clouds give way...

...to blue skies and unbroken sunshine.

In this brief dry spell,

animal fighters step from the shadows

to make the most of the fine weather.

Along one stretch of jungle river,

it's the time for a new generation of creatures

to learn the brutal rules of the forest.

These novices must face their rivals...

...fight to secure a mate...

...and battle for the best food.

Their arena is littered with danger.

The competition is fierce.

Only the toughest will taste victory.

(SNAKE HISSES)

(GROWL)

Beneath towering trees, a winding river cuts its path.

With the rains abating,

the current is already beginning to slow.

For one young animal, it signals a big change.

(SOFT, DRAMATIC MUSIC)

Caiman.

His kind first spread through these jungles

more than 60 million years ago.

At five years old, Caiman is still on his way to maturity.

This dry season is his time to prove himself.

In the drier months,

this stretch of river has everything this young hunter needs.

As the water level drops,

the fish are forced into ever smaller pockets.

Caiman has the perfect strategy, to catch them.

(CAIMAN HISSES)

He fills his lungs with air to float motionless at the waterline.

Faint vibrations from fish swimming nearby

ring like a dinner bell.

His timing must be perfect.

He strikes in under 50 milliseconds.

Caiman's prime fishing spot hasn't gone unnoticed.

Other males want to fish here, too.

(GROWLS)

He emits an infrasonic rumble.

(GROWLS)

His message is clear...

...this territory is taken.

(GROWLS)

The violent vibrations from his scaly back, make the water dance.

It's a visual display to attract mates

and intimidate nearby males.

(GROWLS)

Under the water, it's a thunderous roar

that can ward off rivals up to 2 kilometres away.

One older, larger male, is undeterred.

He senses Caiman's inexperience...

...and wants to challenge him for this territory.

(LOW GROWLING)

(LOW GROWLING)

(DRAMATIC MUSIC BUILDS)

(CRUNCHING)

Caiman locks on.

Jaws lined with over 70 cone-shaped teeth hold his rival fast.

It secures him an early advantage.

(HISSING)

He has his rival pinned,

with one of the most powerful bites in nature.

But the muscles that open these predators' jaws

are relatively weak,

it's impossible to push back.

Instead, his opponent can only rely on his defences.

A reinforced bone above his eye socket,

absorbs the crush and spares his eye.

Caiman continues to squeeze

with enough a force to crush a human skull.

He won't let go until his opponent yields.

But both are tiring.

Caiman, mustn't falter now.

(DRAMATIC MUSIC)

(HISSES) (MUSIC FADES, ENDS)

The older male relaxes his body.

Surrender.

He slinks off into the wings.

Young Caiman's impressive display of dominance,

has earned him the right to continue to fish in this territory.

Along the tangled riverbank,

another young hunter explores the drying undergrowth.

The largest big cat species in the Americas.

(WET GROWL) (LOW, TENSE MUSIC)

Jaguar.

He's the apex predator here.

But at just four years old,

he's in the most precarious phase of his young life.

Jaguars are solitary animals.

And since leaving his mother's side,

he's walked over 80 kilometres in search of a territory of his own.

Finding the right one, is his biggest challenge yet.

The best hunting grounds, are occupied by other males.

He can smell markings left by an older cat,

who passed by here recently.

But he's also sensing something closer.

A potential meal.

On the riverbank, there's plenty of cover for stalking prey.

His rosette-patterned coat, blends with the shadowy undergrowth.

His vision is six times better than ours...

...but to make the kill, he'll need to close the gap.

(BRANCH SNAPS SOFTLY)

In the dry, still conditions, Jaguar must tread with caution.

(BRANCH SNAPS)

(CRIES OUT)

(DRAMATIC MUSIC)

(MUSIC FADES, ENDS)

He can't compete with a tree-loving coati

on thin branches like these.

He needs to find a better place hunt.

Along a bend in the river,

the falling waterline has exposed a sandy beach.

An ideal spot to ambush sunbathing capybaras.

But the sandbank has also been scent-marked,

by the territorial male.

He can't see him, but he senses he's there.

Jaguar continues his quest, elsewhere.

(SOFT MUSIC)

At this time of year,

all the forest's residents are adapting to the drying conditions.

Some creatures stop at nothing

to find even the smallest pool of water.

Strawberry Poison Dart Frog.

A young male, in his first dry season as an adult.

He's scouring the leaf litter for any remaining pools of water.

To ploy, to attract a mate,

because females need water to lay their eggs.

(FROG CHIRRUPS)

At 20 millimetres long,

and navigating a maze of towering plants and predators...

...it's a big journey, for a small frog.

This tiny pool in the cup of a dead leaf

is exactly what he's after.

But someone else is already here, another male.

(FROG CHIRRUPS)

To claim this pool, he'll need to fight for it.

(BOTH CHIRRUP)

(MEXICAN STANDOFF MUSIC)

Frog processes his odds.

His large, dark eyes assess his opponent's hue.

(CHIRRUPING) (MUSIC CONTINUES)

The redder his skin, the more aggressive he is,

the longer the odds of victory.

As a relative youngster,

Frog has never been in a scrap before.

But fighting is in his genes.

Instinct tells him the surest way to secure victory.

Strike first.

Quick-release tendons in his legs catapult him like an arrow

from an archer's bow.

He travels 25 times his body length in a fraction of a second.

(WESTERN MUSIC)

Frog locks on.

He clings to his opponent with eight long, supple fingers.

Tiny suction cups on each tip hold fast on the opponent's moist skin.

(MUSIC CONTINUES)

Strawberry poison dart frogs are champion endurance wrestlers.

These territorial fights can run for over an hour.

Eventually, exhausted from the fray...

...the opponent calls time.

(FROGS CHIRRUP)

Frog's youthful tenacity, has won him victory.

Claiming ownership of this coveted pool of water,

is already paying off.

A female is here, ready to check out the goods.

(FROGS CHIRRUP)

As sunlight floods the canopy...

...even the plants are locked in conflict.

Just 2% of the sun's rays reach the forest floor.

So the vines and saplings must fight to get to them.

The forest is also producing less fruit...

...making figs and berries a precious commodity.

(BIRDS SQUAWK)

This is Coati.

She's a young, tenacious female

well versed in evading the predatory attempts of Jaguar.

She's also a leader.

She's earned her place as the matriarch

of a close-knit group of females, known as a band.

Imprinted on Coati's brain is a map of the jungle canopy.

She knows the locations of the best fruiting trees

and is leading her band on a 2-kilometre trek to find them.

The moist skin around Coati's snout

is packed with sensory nerve endings,

giving her a powerful sense of smell.

She uses it with pinpoint accuracy

to sniff out fruit and insects in the leaf litter.

With sharp, non-retractable claws,

she makes quick work of an armour-plated flat-backed millipede.

But Coati is most at home 40 metres up, in the canopy.

She's found what she's been looking for.

A fig tree, full of fruit.

It's an opportunity for the entire band to feast.

Using their long tails for balance,

coatis are in their element in the branches.

Eating in the canopy is safer.

And it allows Coati to watch for dangers down on the forest floor.

She spots unwelcome company.

A wandering male.

Males aren't tolerated in the group,

apart from brief periods of mating.

But this isn't the breeding season.

Coati has secured this fruiting tree for her band,

there's not enough to share with a large, hungry male

looking to muscle in.

What's more, males will often kill any young

fathered by other males.

The interloper picks his way through the branches.

Coati must scare him off.

(TENSE, DRAMATIC MUSIC)

(SQUEALS)

She lets out a chorus of squeals

and swipes her claws at the male's face.

But he isn't deterred.

(SQUEALING CONTINUES)

He corners her on the end of a branch.

It bows under their combined weight.

A fall from this height could be fatal...

...so the male backs off.

Coati takes her chance to give him the slip.

Time to change tactic.

On the forest floor, she rallies the sisterhood.

(SQUEALING)

By the time the male reaches them, they've formed a united front.

Coati leads the charge.

The band's collective shrieking and biting keeps up the pressure.

The boldest females take turns at mobbing the male.

Together, they overwhelm him.

It may not be the last they see of him...

...but for now, Coati has kept her band safe...

...and they can return to foraging for fruit in peace.

(SOFT MUSIC)

As the forest dry season rolls on, leaves crack and fall.

And creatures of all kinds crawl through the dry leaf litter

searching for food.

As the sun sets, a night hunter creeps from his burrow,

into the moonlit forest.

A giant of the arachnid world.

Orange-Kneed Tarantula.

At four years old, he's entering the prime of his life.

This dry season is the first time he's old enough to mate.

Paired appendages beneath his eyes

are covered in sensitive hairs that can absorb airborne pheromones

through microscopic holes.

He picks up the scent left by a female,

but she's two kilometres from here,

across the dry jungle floor.

It'll take tenacity and good fortune to get there.

So before embarking on this mission, he must feed.

He's a voracious carnivore.

(CRICKET CHIRPS)

And the night forest brings its own unique offering of insects.

His eight, tiny eyes...

...give him an almost 360-degree field of vision.

(RUSTLING)

But he can only detects the blurred outline of shapes.

It's through his front legs

that he picks up the most detailed information.

At the entrance to his burrow, he's set a trap.

An early warning system

of delicately constructed, fine silk.

(CRUNCHING)

Tarantula holds the cricket with his front legs

and drives a pair of 4-centimetre-long hollow fangs

through its exoskeleton.

He injects a powerful venom, paralyzing his prey.

Then pumps in a cocktail of digestive juices

to break down his victim's body tissue.

Finally, he uses his sucking mouthparts

to drink the liquefied insides, like soup.

He'll feed for the next 24 hours.

Then he'll be ready to continue his quest for a mate.

(SOFT MUSIC)

As the sun rises over the jungle canopy...

...Poison Dart Frog is making himself at home

in the area around his tiny pool.

But his new patch is plagued by an infestation.

Poisonous ants.

Luckily, he knows just how to deal with the problem.

He can munch 14 ants every hour.

(SOFT CROAKING)

Downing poisonous insects is no party trick.

He has a taste for spicy food

and deliberately seeks out ants, mites and termites

laced with formic acid.

(SOFT DRAMATIC MUSIC)

His body distils the toxins to make himself fatally poisonous

to any would-be predators.

An ingenious defence strategy.

(RUSTLING)

But one that only works if your enemies know not to eat you.

(LOW, TENSE MUSIC)

(CHIRRUPS)

Following Frog's successful courting of a female,

he's now got even more reasons to keep his patch free of intruders.

(CURIOUS MUSIC)

A precious clutch of eggs.

He'll diligently guard them for the next two weeks.

Long enough for them to hatch into tadpoles.

If Frog can successfully protect them,

his small pool will become a creche.

(SOFT MUSIC)

While Frog is holding ground,

Jaguar is still searching tirelessly for a territory of his own.

He's had no luck finding an unoccupied patch.

So, his quest has led him back to the exposed sandbank.

A prime hunting spot.

Jaguars communicate with each other

by leaving pungent scent markers across their range.

They're odorous calling cards that broadcast their status.

Jaguar, can smell that this area is well used by an older male.

The rival's scent on this side is fresh.

But there's a chance the far bank is unoccupied.

He's the strongest swimmer of all the big cats.

And with the river so low, it's just a short crossing.

(LOW, TENSE MUSIC)

It's not just Caiman following his every move.

(GRUNTS)

The established male is here,

laying claim to this riverbank too.

Jaguars rarely fight for territory.

An injury could prevent them from hunting successfully.

In effect, a death sentence.

So their rule is finders keepers.

But Jaguar has few good options.

He calculates that this riverside hunting ground is worth the fight.

(GROWLS)

Jaguar keeps his back to the grass, sizing up his rival.

(GROWLS)

A ligament behind his nose vibrates to produce a guttural growl.

(GROWLS)

A final warning.

(HISSING GROWL)

Jaguar lunges.

His 5-centimetre-long claws

narrowly miss his opponent's soft belly.

(LOW, TENSE MUSIC) (GROWLING)

The rival swings one back.

Jaguar launches with both paws.

(GROWLING)

Manoeuvring to keep his high vantage point, he goes again.

With his head and body low to the ground...

...he delivers a powerful vertical down-swipe.

His rival senses that Jaguar isn't going to give up.

And so, to avoid serious injury, he retreats.

Jaguar's gamble has paid off.

Now he's laid claim to this spot...

...his hunting opportunities will be greatly improved.

It won't be easy for a young jaguar to hold this territory.

But he has shown that he has the necessary strength and courage

to match his rivals.

(SOFT MUSIC)

Nocturnal Tarantula is so focused on his mission to find a female

that he's still out and about in broad daylight.

For three days, he's been roaming the jungle.

Lured by the lingering scent of a potential mate,

he's ventured more than a kilometre from his burrow.

Coati and her band have been happily gorging themselves

on fresh figs.

But fruit isn't the only thing on their menu.

Coati is an opportunistic omnivore.

90% of her day is dedicated to foraging.

And her powerful nose is primed to seek out anything edible.

Tarantula must proceed with caution.

His vision may be limited,

but he can sense a mortal threat.

Coati's finely-tuned senses are tingling too.

She smells the spider nearby.

Tarantula retreats into a hiding hole...

(RUSTLING) ...hoping Coati moves on.

But she won't pass up a high-protein snack so easily.

(LOW, TENSE MUSIC)

Tarantula raises his head and legs, exposing his venom-loaded fangs.

But she isn't deterred

and thrashes at the spider with her front paws.

Tarantula goes into fight mode.

He spins around and aims his rear at Coati.

Using his hind legs, he flicks out,

dislodging a volley of microscopic hairs.

Each is armed with a stinging barb.

(SQUEALS)

They lodge in Coati's fur,

causing severe itching and irritation.

As she's scratching in pain,

Tarantula seizes the opportunity to slip past.

Spotted.

Aggravated by the spider's defences,

Coati strikes even harder.

With arms outstretched, she paws at Tarantula,

then rolls him...

...trying to strip the irritating hairs from his body

to make him more palatable.

But Tarantula's barbed hairs infiltrate her coat.

He makes his escape.

While Tarantula and Coati are parting ways...

(FROG CHIRRUPS)

...Frog's game plan is all about staying put.

His hard-won territory is now the centre of his world.

At its heart, his clutch of eggs...

...now just a few days from hatching.

But as the forest continues to dry out,

damp pools worthy of a female's eggs are becoming increasingly rare...

...making Frog's patch even more appealing to outsiders.

Invaders are closing in.

(CHIRRUPING)

Nearby, a male calls,

signalling that he wants this territory.

And he'd happily eat Frog's eggs for breakfast.

Frog has battled hard for this spot.

(CHIRRUPS)

He'll do whatever it takes to deter the intruder.

(FROG CHIRRUPS)

He aims a volley of repetitive croaks, towards the rival.

Not just loud, but precisely timed.

(REPETITIVE CHIRRUPS)

His calls match the intruder's signal...

(CHIRRUPS)

...in volume and tone.

The message? "I'm bigger than you."

"And I'm stronger, too."

But the intruder is undeterred.

Frog steps things up...

(DEEP REPETITIVE CHIRRUPS)

...bellowing a louder, deeper warning.

But the rival stands firm.

The fight is on.

It will be a test of endurance.

A battle to exhaustion.

The intruder peels away, then launches himself at Frog.

Both contenders desperately try to gain the upper hand...

...flipping each other over and over.

(TENSE, DRAMATIC MUSIC)

Frog is trapped.

His opponent's long arms tighten, choking him.

Frog's legacy hangs in the balance.

More than an hour ticks by, but neither is willing to yield.

It's time for Frog to execute his special move.

Using his sticky fingers,

he grips his opponent in a half nelson

and with his last reserves of energy...

...he delivers one last slingshot.

His rival is utterly exhausted.

Frog is tired too, but he's protected his eggs.

He's the undisputed champion of this small patch of forest.

And under their father's watchful eye,

this next generation of poison dart frogs

now have a fighting chance.

On the riverbank,

Jaguar is patrolling his new territory.

His defeated rival has left him in peace

to focus on finding food.

The trees overhanging the river's edge

provide ideal hunting cover.

The perfect spot to launch an ambush on any prey hiding underwater.

Jaguar's wide-padded paws allow him to walk almost silently,

so as not to alert his quarry.

He needs to find an overhang with a clear view down to the water.

Jaguars have been known to take caiman

up to three metres in length.

But they're a dangerous prey.

A caiman's defensive bite can cause a serious injury,

even death.

Caiman's turret-like eyes sit above the waterline.

But his vision has a weakness, a blind spot.

Behind him.

The indigenous name for jaguar means "he who kills with one leap."

His strategy is to launch himself onto Caiman,

and deliver a piercing bite to his skull.

He extends his hind legs like huge, muscular springs

hurling him over three metres through the air.

But in the thick vegetation, Jaguar misses his mark.

Caiman reacts in an instant.

He grips on to Jaguar, whips his tail,

and pulls him into a death roll, trying to drag him underwater.

Jaguar is an expert at holding his breath.

But Caiman can stay submerged for up to an hour.

Jaguar finds a footing to grab a breath.

But both animals are tiring.

Caiman's thick skin is among the toughest in the animal kingdom,

but Jaguar grips hard with his claws and teeth...

...and slowly drags him to the bank.

(TENSE, DRAMATIC MUSIC)

In the shallows...

(CRUNCHING)

...Jaguar uses his muscular jaws, to deliver a final, powerful bite

that crushes Caiman's skull.

It's a huge meal that will feed him for many days...

...giving him the energy he needs to patrol

and mark out this new territory.

If he can stay here through the rains,

there's every chance he'll be able to secure a mate.

Across the forest, Tarantula's marathon hike is over.

The female he's been following, has welcomed him to her burrow.

But the danger isn't over.

He'll likely end up as her post-coital snack.

Such are the rules of the jungle.

(THUNDER)

As the curtain falls on the dry season...

...the river swells.

The remaining caiman can escape the confines

of their territorial pools and spread out once more.

For Poison Dart Frog, the rains bring relief.

The entire forest floor is awash with puddles...

...drawing the attention of other males away from his territory.

His duty of care is nearly over.

The tadpoles' mother will soon return to delicately ferry

each of her young to pools of their own.

When they grow to maturity,

they too will enter this arena to fight for their own patch...

...along the jungle river.