Our Planet (2019) s01e03 Episode Script

Jungles

1 Just 50 years ago, we finally ventured to the moon.
For the very first time, we looked back at our own planet.
Since then, the human population has more than doubled.
This series will celebrate the natural wonders that remain and reveal what we must preserve to ensure people and nature thrive.
[animals whooping.]
This is a tropical forest.
A rain forest.
The richest habitat on Earth.
Exactly how many species rain forests contain is unknown, but it runs into millions.
And new ones are discovered every week.
There are some, like this clouded leopard, we still know virtually nothing about.
Although they cover just seven percent of the world's land area, jungles play a vital role in the health of the planet.
In the heart of Africa lies the Congo.
It is our planet's youngest rain forest, a mere 18,000 years old, and it's the jungle with more big animals than any other.
A family of lowland gorillas.
They're led by this silverback, the dominant male.
He's as tall as a man, but twice the weight.
His family depend on him for survival.
As their guardian, he must keep a lookout for danger.
A rival male might usurp him and tear his family apart.
But there is one threat beyond his control.
In the last 20 years, poaching for bushmeat has halved the Congo's gorilla population.
His kind are now critically endangered.
[grunts.]
[elephant huffs.]
It's only a forest elephant, which needn't concern the silverback.
[low trumpeting.]
But the elephant has reason to be wary of poachers too.
Their long straight tusks are even more sought after than those of their grassland cousins.
He follows paths made by generations of elephants before him, searching for food.
Like the elephant, the silverback's family will travel several kilometers a day, looking for fruits and seeds.
They and the elephants are the gardeners of this jungle.
The seed dispersers.
And many of the trees here owe their existence to these large animals.
Here, all paths eventually lead to Mbeli Bai.
Open areas like this are a unique feature of the Congo's jungles, and there are more than a hundred dotted throughout the forest.
Known as bais, these clearings attract many of the jungle's inhabitants.
[elephant brays.]
The silverback cautiously leads the way, but his family are close behind.
The gorillas come to feed on aquatic plants rich in salt, a mineral in short supply inside the forest, but crucial to their survival.
Elephants mine salts from the mud using their trunks.
Or just drink the mineral-enriched water.
The silverback's family are not the only gorillas here.
Nearly 200 others also use this bai, as well as more than 530 elephants, a measure of Mbeli's importance.
For the elephants, the bais have another vital role.
Most of their lives are spent roaming the vast forested interior on their own, so it's only here they get a chance to meet others.
Unlike most of the Congo's other bais, Mbeli is well protected, making it a refuge from poaching.
It's only when they leave that the danger returns.
And as the Congo's main seed dispersers, the loss of its megafauna could have a far-reaching impact on the future of our planet's second-largest rain forest.
Jungles may look the same, but each is home to a unique cast of characters.
New Guinea is the world's largest jungle-covered island, and more than half of its plants and animals are found nowhere else on Earth.
Its turbulent geological past has shaped this vast island into a dramatic landscape of mountains and valleys.
A process that isolated one species from another.
Separated in this way, New Guinea's animals have become truly bizarre.
The male twelve-wired bird-of-paradise is the only bird in the world that has tail ornaments like this, used to tickle the face of a prospective mate.
From one crow-like ancestor, birds-of-paradise have evolved into 40 different kinds.
Every corner of this island has its own version.
Meet the black sicklebill of New Guinea's highlands [croaks.]
able to morph into some very un-birdlike shapes.
Each male bird-of-paradise has a unique display for attracting mates, and none is more extraordinary than the one that takes place on this stage.
For the owner, a western parotia, there's work to be done first.
Every morning, he clears his court of the night's fallen debris.
It's a vital chore if he wants to attract a mate.
Females only visit the tidiest courts, so one rogue leaf might ruin his chances.
[squawks.]
Perfect.
His obsessive housework pays off, and a female drops in for a closer look.
Now is his chance to really impress, but it won't be easy.
Females are very fussy, and she'll expect his carefully choreographed routine to be faultless.
He opens with a bow.
Next, his blue eye must flash yellow.
So far, so good.
He has all the moves.
Fancy footwork.
The whirling dervish.
The head plume shuffle, with spin.
Her erect head feathers and quivering wings are a very encouraging sign.
His sidestep and head bob look good from any angle, but his crowning glory can only be appreciated from her perspective.
Wait for it.
There it is.
A flash of his iridescent throat patch.
Her excitement grows.
His performance has been a triumph, and he wins her approval.
New Guinea's isolation has created a unique variety of animals, but the age of a forest has an even greater impact on the diversity of life it contains.
The jungles of Borneo, in Southeast Asia, have grown here for nearly 130 million years, making them the oldest on Earth.
This limestone mountaintop in Borneo's highlands was originally formed under the sea.
Time and rain has slowly shaped this jungle fortress into these 40-meter towers.
The great age of this island's jungle is best illustrated by one of the oldest predators on Earth.
A velvet worm.
Completely at home on the humid forest floor.
They've been here since the age of the dinosaurs, and have remained virtually unchanged.
It detects its insect prey through vibration and touch.
But with no turn of speed, how does it capture these fleet-footed critters? The answer is stranger than fiction.
Glue guns.
The sticky slime hardens on impact, trapping the luckless insect.
The velvet worm will inject the cockroach with digestive saliva, and then suck out its insides.
The high humidity of the forest floor isn't just good for velvet worms.
It's perfect for fungi, too, and Borneo's ancient jungles are rich in species.
By decomposing the dead, the slime molds and fungi recycle scarce nutrients.
Time has made Borneo's jungles extraordinarily rich and diverse.
Here, in just a few hectares of forest, there may be more kinds of plants than in the whole of Europe, including some of the most specialized on Earth.
Over several weeks, these growing tips inflate to form jugs or pitchers.
There are 39 kinds of pitcher plant in Borneo, and most are found nowhere else.
To get the nutrients they need to survive, pitcher plants rely on animals, often in surprising ways.
This is the mountain treeshrew, an animal found only in Borneo.
Every morning, the treeshrew visits his neighborhood pitchers.
It depends on the sugary solution that exudes from hairs on the pitcher's lid.
When he's licked this lid dry, he'll move to another.
And then another.
Eventually, all that sugar can have only one result.
[splat.]
In return for the free food, the treeshrew leaves a gift.
Fertilizer for the plant.
All that's needed is an afternoon shower to flush the shrew poo into the pitcher's bowl.
Without these added nitrates, the plant couldn't survive.
And the quest for nutrients has led some pitchers down a sinister path.
A gracilis pitcher plant attracts ants to the underside of its lid with drops of nectar.
But what do the ants give in return? It's a story that also depends on rain.
The force of the raindrops make it impossible for the ants to hold on.
It's the plant world's only springboard trap.
This pitcher plant feeds on ant bodies.
All pitcher plants depend on animals for survival, and one has even gone into business with a bat.
The woolly bat finds hemsleyana pitchers because the plant's broad back wall reflects the bat's ultrasound.
The tube-like pitchers are the perfect roosting site.
The pitcher provides secure accommodation and the plant is enriched by its guest's deposits.
Relationships like these have taken millions of years to evolve, but many could be gone in a decade.
In the last 50 years, Borneo has lost over half of its jungle.
And it's even worse on the neighboring islands of the Philippines.
Here, 90 percent of the primary rain forest has gone.
What's left is the last refuge for the world's rarest bird of prey.
The mighty Philippines eagle.
[caws.]
With just 400 pairs remaining, a chick on a nest is a very scarce sight.
Scientists have tracked the mother since she was a year old.
Now aged ten, this is her first chick.
It's four months old, already nearly a meter tall, and increasingly confident.
Although Mother still likes to give a helping hand.
The chick is very demanding.
She expects regular food drops, but, like a toddler having a tantrum, she doesn't want any help at mealtimes.
[cawing.]
Already, she's the same size as her father and too big to argue with.
But if his youngster is to take her next steps, he knows it's time for some tough love.
From now on, visits will be less frequent.
[caws.]
The parents drop by with an occasional food parcel, but a small fruit bat isn't much to get excited about.
It's confusing when your parents don't visit as frequently as they once did.
[caws.]
Every day, she calls, but no one is paying any attention.
She's hungry, and all that's left are scraps.
It's time to become a proper eagle.
Flapping strengthens flight muscles in two-meter wings.
Wings that will be used to carry off her hefty prey.
Though that skill is still some time off.
So far, she's never ventured beyond the security of her nest.
And with good reason.
There's a 70-meter drop to the forest floor.
A fall would be fatal.
It's a nervous moment, but she must persevere.
Right now, she's all toes and talons.
Sudden gusts of wind are not helpful when balancing over a death-defying drop, and the daily downpours don't make it any easier.
Every day, she gets a little stronger and more confident.
Then, the day comes when confidence finally matches know-how.
Now is the moment to reach for the sky.
Her first ever flight from her nest tree.
It'll be nearly a year before she's fully independent.
Then, her survival will depend on finding a territory with large stretches of unspoilt jungle.
In the Philippines' fragmented forest, there's just too little prey for a supersized eagle.
But there is one jungle whose size is still legendary.
The Amazon basin is over 3,000 kilometers across and home to half of our planet's remaining rain forest.
But there are challenges for those living in the Amazon's deep interior.
[birds hoot and chirp.]
Black spider monkeys, with eyes on a salt lick.
Being so far from the sea, salt is in short supply here, so a visit to a lick is essential.
But first, they must be sure there are no predators lurking below.
A harmless agouti is a good sign.
This is the only time a spider monkey ever sets foot on the ground.
And if you have your head in a hole, best to have a lookout.
Monkeys can't survive without these minerals, and predators know it.
[chitters.]
A warning from the lookout.
It's not a false alarm.
A jaguar.
Rarely seen, but the Amazon's top predator.
With the jaguar gone, the monkeys return, but it's a risk.
Nobody knows when the predator will be back.
It's not just spider monkeys for whom fear must give way to need.
In the Amazon, salt licks are as vital as an oasis in a desert.
Noises could be friend or foe, so every visitor must remain poised for flight.
[rustling.]
[cawing.]
It's a false alarm.
Just the harmless agouti again.
In the Amazon, every animal group has more species than anywhere else.
And that includes frogs.
There are thought to be over a thousand different kinds of them here, and new ones are still being discovered.
Frogs are an indicator of a healthy forest, but its most important residents are the jungle's smallest inhabitants.
There are thought to be over two million kinds of insect in the Amazon.
These are the most numerous.
A colony of leafcutter ants can run into the millions.
Each colony is a superorganism with a collective function to gather leaves and carry them back to their underground nests.
Within the territory of a leafcutter colony, as much as a fifth of all new plant growth will be harvested by the ants.
Slicing through leaves with specialized mandibles, they produce high frequency vibrations, which stiffens the leaf, making it easier to cut.
Working together, they can strip a tree bare in 24 hours.
The trick is holding on to your leaf as you fall.
Easier said than done.
But best not to return to the nest empty-handed.
A leafcutter colony is like a mega-herbivore, not dissimilar to an elephant in the Congo, and their impact on the ecosystem is just as important.
The ants follow scent trails back to the nest, dodging unexpected obstacles.
But to increase efficiency, the ants keep their paths clear of debris.
A leafcutter nest can be up to eight meters deep and have thousands of interconnected chambers.
The workers carry the freshly harvested leaves to special rooms for processing.
The leaves are not food, but used to create gardens of fungus, which they feed to their larvae.
The success of the colony depends on keeping their gardens disease-free.
So, the ants have teamed up with bacteria to help control pathogens, which would destroy their precious fungi.
Scientists now believe these bacteria could provide new solutions to human diseases.
But as successful as these ants are, the rain forest's diversity depends on no one species gaining the upper hand.
[animal hoots.]
Here, ants don't have it all their own way.
This one is behaving oddly.
It seems compelled to climb upwards, and is already several meters above the forest floor.
Something has taken control of its movements, like a puppeteer pulling at the strings of a marionette.
There's just one final act, for which the ant has no choice.
It must find a place to bite down, tethering it to the vegetation.
With the ant in its death grip, a parasitic fungus, Cordyceps, erupts from its body.
Finally, the fruiting body of the fungus bursts from its head.
From this bulbous container, spores will be cast into the air currents, where they will claim more ant victims.
But it's not just ants.
Many others are infected by the Cordyceps fungus.
The more numerous a species is, the more likely it is to fall victim to the killer fungus.
Checks and balances like these means no one species can ever dominate, so protecting the jungle's incredible diversity.
But today, the diversity of the world's rain forests is falling at an alarming rate, and that is because of us.
We have now replaced up to 27 million hectares of virgin jungle with a single species of tree.
This is oil palm, one of the world's most productive crops.
But these monocultures support only a fraction of the diversity found in primary rain forests, and it is pushing many animals to extinction.
In the swamp forests of northern Sumatra, in Indonesia, time is running out for one of our closest ancestors.
The orangutan.
A baby orangutan takes more than ten years to become independent.
Everything must be learned from its mother.
Like how to bridge the gaps between trees.
Survival depends on each orang understanding its patch of forest perfectly.
Watching scientists have named this pair Ellie and Eden.
Ellie is 18 years old, and Eden, her first baby, is three.
Right now, he needs a little bit of encouragement.
Like all orangutans, Ellie has a mental map of her surroundings, including the location of every fruiting tree.
Eden needs to learn this, too, but for now, he must watch everything his mother does, learning not just what's edible but also how to eat it.
Every day is a new lesson for Eden.
Here, ants are a big part of their diet, and there's a knack to gathering them.
Once tangled in Ellie's fur, they're easy to pick off.
For little Eden, it's all about watching and learning.
Eden's cousin, Louis, is more experienced.
Four years older than Eden, he can move through the branches with ease.
It's taken a few years to master, and it's clearly a skill he feels is worth showing off.
Conquering the treetops is just stage one in an orangutan's education.
To survive, Louis must learn more.
Much more.
His mother, Lisa, has found a rotten tree trunk with lots of ants.
But this anting opportunity requires more know-how.
To get them, Lisa must break sections off.
At his age, Louis must do more than watch.
He must copy.
Not a bad effort.
But even at the age of seven, he's yet to master the art of ant capture.
Louis has much to learn.
Pluto, on the other hand, graduated a long time ago.
Thirty years old and nearly a hundred kilograms, he is king of this jungle.
His cheek flanges are a sign of power, something for Louis to aspire to.
Pluto is constantly on the lookout for food, and he's just spotted a promising opportunity.
These wasps mean one thing to him.
Tasty grubs.
To get at them, he favors a smash-and-grab technique.
His thick fur protects him from most of the angry wasps, but the rewards are worth risking a few stings.
Louis keeps his distance.
He would need to be a lot bigger and hairier before he could do battle with wasps.
But here, there's one trick that can take half a lifetime to get to grips with.
Louis' mother, Lisa, has learned how to make tools from sticks, to winkle out insects.
The orangutans living here are the only ones in the world to have discovered this skill.
Louis must try and learn it too, but it may be another eight years before he's as good as his mother.
This long education has made orangutans particularly vulnerable to changes taking place in their forest.
It's now estimated that we lose 100 orangutans every week from human activity.
Louis and Eden's generation could be the last wild orangutan.
When Pluto was their age, his jungle home stretched to the horizon.
Not anymore.
In the last four decades, the pristine lowland jungle that orangutans depend on has declined by a staggering 75 percent.
Across the world, we are losing tropical forest at the rate of nearly 15 million hectares every year, and with it, the planet's treasure trove of diversity.
Jungles store and capture more carbon than any other habitat on land.
They cool our planet, provide food and medicines.
We lose them at our peril.
Please visit ourplanet.
com to discover what we need to do now to protect our jungles.
I can hear the whole world Singing together I can hear the whole world Say it's now or never 'Cause it's not too late If we change our ways And connect the dots to our problems I can hear the whole world Say we're in this together We're in this together
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