Original subtitles

NARRATOR: \hIn an African wilderness,

giants roam

and killers prowl.

But behind these superstars

is a cast of characters that is often overlooked.

These unsung heroes keep the whole show on the road.

They fertilize the earth,

pollinate the plants,

and keep the place clean.

No one creature survives here in isolation.

An intricate network of plants and animals connects,

in one of the world’s most remarkable ecosystems.

In Zambia, in the heart of tropical Africa,

lies the Luangwa Valley,

one of the most remote areas of wilderness on the continent.

Much of it is covered in woodland.

Over 300 species of trees thrive here.

For the valley’s biggest mammal,

that’s a lot of food.

And they need it.

An adult African elephant

needs a daily intake of 70,000 calories to survive.

A five-tonne bull munches through

600 pounds of vegetation in 24 hours.

Elephants don’t ruminate.

Their food passes through 60 feet of intestines in just 12 hours.

And they digest less than half of what they eat.

The rest pops out as dung.

A lot of dung.

Over 300 pounds each day.

It’s an end product for elephants,

but to many other animals, it’s just the beginning.

For a bush squirrel, a bolus of dung is a box of delights.

Elephant dung is mostly fibre

and contains very few bacteria.

Rootling through it is not as unpleasant as it might seem.

Undigested seeds hidden inside are a tasty treat.

Baboons too know the merits of searching through elephant dung.

Even less than fresh heaps are worth a rummage.

There might be a juicy insect inside.

But the real dung specialists are beetles.

This male has sensed a fresh dollop.

His sense of smell is so good

he can find dung just one minute after its hit the ground.

There are more than 4,000 species of dung beetle in Africa.

A hundred and fifty species use only elephant dung.

He’s not going to eat it straight away.

He’s taking this meal to go.

He manipulates the dung with specially adapted mouthparts.

And uses his strong front legs to help him mould it

into a handy transportable ball.

Meals on wheels.

He pushes it in reverse, almost standing on his head.

Spurs on his back legs help him grip the ball

and guide it in a straight line.

Dung beetles are, proportionally, stronger than elephants.

they are among the strongest animals on Earth.

The beetle can move a dung ball 40 times his own weight

over distances up to 75 yards.

That’s like you or me single-handedly pushing a car

across 25 football fields.

He’ll bury his dung ball to feed on later or,

if he’s lucky, a female will lay her eggs in it.

Dung beetles are nature’s muck spreaders,

distributing elephant fertilizer across the savannah.

Seeds hidden in the dung germinate

and nutrients go back to the soil

to nourish the very trees where it all began.

It’s not only elephants and dung beetles

that play a role in tree planting in the Luangwa Valley.

Baboons spend two-thirds of their day foraging

and will eat almost anything they can get their hands on.

They’re messy eaters.

The fruits are full of juicy pulp and seeds,

but the tough pod cases can be hard to break into.

Baboons have the tools for the job.

A male’s canine teeth can be two inches long.

Natural nutcrackers.

Time to move on.

Baboons can travel up to six miles a day when searching for food,

which means any seeds they’ve eaten

get carried far from the parent tree.

And what goes in, must come out.

Every time they answer a call of nature,

they’re effectively planting a seed.

Baboons often use termite hills as lookout posts.

Any deposited seeds can germinate on top of the mounds,

which is why you see so many tamarind trees

growing out of termite hills.

It’s a phenomenon that goes back generations.

This tree is over 150 years old,

which means the termite mound it’s growing on is even older.

Baboons have been unwittingly planting tamarind trees

here in the Luangwa Valley for centuries.

The roaming baboons meet many of the valley’s residents on their daily foraging trips.

And their presence is often advantageous for their neighbors.

A fruiting fig tree is a magnet for the hungry troop.

But the sweet-toothed baboons

will only eat the ripest fruits.

Sour figs are rejected after one bite.

But just because it’s discarded,

doesn’t mean it’ll go to waste.

Elephants provide baboon food in their dung,

but the troop return the favor

when they drop unripe fruit.

Another hungry animal lurks in the leaf litter.

A corn cricket.

Any scraps overlooked by the elephants are a feast.

His massive mandibles cut and crush through any fruit or carrion he finds.

Sensory palps are the equivalent of our tongue,

tasting his food.

After a sticky meal, it’s time to clean up.

His long antennae help him detect food in the undergrowth.

It’s important to keep them in tip-top condition.

Other animals benefit from the baboons’ messy eating habits.

Seasonal winterthorn pods are a rare treat for the river troop.

With the help of the untidy baboons,

impala get to share spoils that would usually be out of reach in the branches.

It’s not altruism, it’s a happy accident.

But it’s just one of the ways impala benefit from hanging out with baboons.

For a prey animal, this valley is a dangerous place.

Ambush predators could be hiding anywhere.

Impala rely on their senses to keep them alive.

Keen hearing and an acute sense of smell

help them detect hidden threats.

In this case, the local leopard, known as Kamuti.

And the impala have recruited some help.

Baboons have sharp eyesight,

and from their treetop lookouts

often spot predators first.

(BARKING)

The river troop’s alarm calls to each other become public service announcements,

benefitting everyone in earshot.

(BARKING CONTINUES)

There’s another primate here who’s taken this communication network to another level.

Vervet monkeys have distinct calls for different types of threat.

(CHITTERING)

This call means "leopard."

Other vervets immediately know the danger’s likely to be slinking through the grass

and bolt up a tree to safety.

(CHITTERING)

A shorter, more clipped call...

(TRUNCATED CHITTERING)

...denotes an eagle...

(TRUNCATED CHITTERING)

And warns the monkeys to take cover.

They also have a call for snake.

(CHITTERS)

It’s a simple language,

but if you’re a vervet, it could save your life.

But the real sirens of this valley are squirrels.

(CHATTERING)

They shout about anything and everything.

Kamuti’s been spotted again.

(CHATTERING)

Squirrels are only six inches long,

but they’re some of the noisiest animals in the bush.

Their urgent alarm calls can shift a sleeping leopard from a tree

or blow the cover of a mongoose hunting for eggs.

Once they get going, everything in the bush is on edge,

and any predator might as well give up.

Kamuti doesn’t stand a chance of hunting now.

Herbivores are the key link in a vital food chain

that converts energy from plants into meat for carnivores.

The energy originates in the sun,

and in the tropical Luangwa Valley,

12 hours of sunshine every day

means plants have plenty of time for photosynthesis.

But to keep the cycle going here,

plants need to reproduce.

Because they can’t move,

plants, like this wild jasmine,

need a little help to transfer pollen

from the male part of the flower to the female part.

Like the jasmine, this acacia tree flowers in the dry season.

Its little blossoms attract pollinating insects from far and wide.

But the most striking blooms in the valley are the flowers of the sausage tree.

They are the largest in the African bush.

Huge stems, two feet long,

each bearing a cluster of four-inch blooms.

They’re irresistible to bees.

(BUZZING)

Hidden inside the velvet trumpets

are puddles of nectar,

up to a teaspoonful in each one.

Every time a bee goes to a different flower,

she carries a dusting of all-important pollen with her,

fertilizing the plants she visits.

Bees can travel several miles from home looking for nectar,

but this one is lucky.

Her hive is in a hole in the sausage tree’s trunk.

(BUZZING)

There can be tens of thousands of bees in one colony,

mostly workers who are all female.

They do all the chores around the hive.

As well as foraging for food,

they clean and guard the nest hole.

A sausage tree home has definite advantages,

but living here does come with risks.

Bees have their nemeses.

Hidden among the stems is a predator,

a praying mantis.

Its disguise is the perfect adaptation to hunting in vegetation such as this tree.

Its huge compound eyes

each contains 10,000 light receptors called ommatidia.

Each of these faces in a slightly different direction,

giving the mantis a very wide angle of view,

up to 245 degrees.

It’s almost like having eyes in the back of your head.

Mantises are ambush predators,

the leopards of the insect world.

The bee has no idea it’s there.

There’s no escaping the mantis’ powerful grip.

It eats the bee alive.

Fat and happy predators, small and large,

are a sign of a healthy ecosystem.

The apex predators in the Luangwa Valley are lions.

They keep the populations of prey species in check and drive biodiversity.

Some animals here benefit from these big cats in surprising ways.

At first glance, a lion and a butterfly have nothing in common.

But their lives do connect.

The butterflies’ antennae and legs are dotted with scent receptors

that help them locate food.

They’ve been drawn to the pungent smell of a lion kill.

(LION GROWLING)

Lions open the carcass at the softest places, often the belly.

The stomach is full of partially digested grass,

perfect for a thirsty butterfly.

They’ll feed on anything that can provide minerals and moisture.

A lepidopteran feast laid on by lions.

Even nectar-loving bees are partial

to a mouthful of salty dung juice on a hot day.

The feeding insects help clear up leftovers.

They’re all part of an extensive bush recycling team.

Lions and leopards tend to eat the choice parts of a kill,

protein-rich muscles and organs.

There’s plenty left over,

sinews, bones, hair and skin.

Spotted hyenas are proficient hunters in their own right.

They’re also scavengers and are not above clearing up other hunter’s scraps.

They will eat far more of a kill than cats do.

They are nature’s dustbins, incredibly efficient waste-disposal units.

Their chests and necks are packed with muscle that powers a robust jaw.

Their domed skulls and enormous premolar teeth

are adaptations for crushing bone.

(BONE CRACKS)

They exert 40% more force in a bite than a leopard.

But they don’t just break bones,

they also swallow and digest them.

Their stomachs are full of concentrated hydrochloric acid

strong enough to dissolve just about anything that goes in,

hooves, hair, teeth and bone.

They eat so much bone

that the calcium in their diet turns their feces chalky white.

And they don’t care about "use by" dates.

The rotting flesh on a fly-blown buffalo leg that’s several days old

would put off most meat eaters,

but for this hyena it’s a tasty midnight snack.

Remarkably, hyenas have competition for these gruesome remains.

Vultures are another key part of the Luangwa Valley’s waste-management service.

They have an incredible ability to find a carcass in the wilderness.

Broad wings generate lots of lift

so they can fly very high,

5,000 feet or more.

The centre of their field of view is magnified,

giving them super-sharp vision

and allowing them to spot a potential meal

from a mile up in the sky.

They also look out for other vultures on the wing.

As soon as one drops to a carcass,

others quickly follow.

Lappet-faced vultures are the largest in Africa

with a wingspan of nearly nine feet.

Big and belligerent, they usually dominate a carcass,

but this time they’re outnumbered.

White-backed vultures are the most numerous on the African savannah.

Hundreds can gather together to feed.

Even the hyenas are forced off their meal.

The vultures’ featherless heads and long necks

are perfect for poking into any orifice.

And like hyenas they have powerful stomach acid

which neutralizes the toxins in dead flesh.

Hanging about on the edges of the melee are hooded vultures.

They’re too small to compete in the feeding frenzy,

but they’ve carved out their own little niche here.

(GROWLING)

They follow lions.

Whenever the pride makes a kill,

these little vultures are on hand to hoover up any stray mouthfuls.

But their relationship with the big cats goes even further.

Hooded vultures spice up their diet with lion poo.

Surprisingly, even this has something to offer.

With the cats’ purely carnivorous diet,

lion droppings are full of protein.

The vultures’ resilient digestive systems

mean they can exploit this peculiar food source.

They even fight over it.

(CHITTERING)

It’s an acquired taste.

Even Charles Darwin called vultures disgusting,

but their reputation is undeserved.

They are a vitally important cog in this ecosystem.

Without them, festering waste would linger far longer,

potentially spreading disease.

And the humble hooded vulture’s willingness to inhabit

such a specialized niche

helps drive biodiversity.

The more types of food different animals will eat,

the greater the variety of species one place can support.

Dung is the basis of an aquatic food chain here, too.

The hippos in the Luangwa River

eat 90 pounds of grass every night.

And that translates into 45 pounds of dung,

mainly deposited in the river where they spend most of the day.

Tail-paddling spreads manure and is a show of dominance or displeasure among hippos.

And it dumps tonnes of nutrients into the river each day.

Perfect fish food.

And in turn, the fish provide food for many species of birds.

A greenshank usually probes for worms in the mud,

but its upturned beak means it can also skim for tiny fry.

Outstretched wings help a saddle-billed stork

keep its balance as it chases prey in the shallows.

It can swallow a fish weighing nearly three pounds

and measuring almost a foot.

A green-backed heron is an ambush predator.

It lies low on the river bank

waiting to pounce on any unsuspecting fish that comes to the surface to feed.

Its deceptively long neck allows it to strike its prey like a snake.

The fish in the Luangwa River also fuel the largest predators in Africa,

Nile crocodiles.

The 20-foot adults could be 100 years old,

but they’re only eight inches long at birth.

They grow continuously all their lives,

feeding on progressively larger fish

and eventually graduating to mammalian prey.

The Luangwa River is home to thousands of crocodiles,

and it’s all thanks to hippo fertilizer.

In still waters like this lagoon,

hippo dung also nourishes plants.

Nile cabbage grows all over tropical Africa.

It spreads quickly, often carried between waterways by hippos.

It’s a juicy meal for many lagoon residents.

Both above the water surface

and below it.

The pond life that nibbles the dangling roots is food for wading birds.

Open-billed storks have long beaks

which let them probe deep into the carpet of vegetation.

Pads on the inside of the strong mandibles give them vice-like grip

perfect for catching fish and freshwater snails.

Birds with short bills can’t reach such hidden delicacies

without a little help from a third party.

As well as fertilizing the crop,

hippos help jacanas with their harvest.

Even out of the water,

hippos provide a helping hand to birds.

As these titans walk, they stir up tiny insects.

The smart place to be when these giants pass by is down at ground level.

It’s like gulls following a fishing trawler.

This relationship is also apparent at night.

But after dark, it’s not birds following them

but bats.

Bats will feed anywhere there are insects.

The distinctive perfume of a warthog burrow attracts plenty of flies,

an ideal bat hunting ground.

A fetid hyena den is even better.

In some cases,

these little acolytes don’t just reap benefits,

they do something in return for their meal.

Oxpeckers feed on mammalian parasites.

And in doing so,

they provide a comprehensive pest-control service.

Kudus and buffalos seem to be favorite oxpecker haunts.

These are both species that spend lots of time browsing in thickets,

a hotbed of tick activity.

The more ticks you carry, the more oxpeckers you need to keep them in check.

Puku are obligate grazers. They only eat grass.

They spend less time in thick undergrowth,

so are less prone to picking up parasites.

They’re not worth an oxpecker’s effort.

Hundreds of puku keep Luangwa’s short-grass plains trimmed.

These big herds of herbivores have a huge impact on the landscape here.

A thousand buffalo

can eat 15 tons of vegetation between them in a single day.

But under their feet are hidden creatures with even greater influence.

Termites.

They’re so numerous,

collectively they weigh more than all the mammals combined in the ecosystem.

They feed on dry grasses,

following pheromone trails as they drag morsels back to their underground nests.

Blade by blade,

they consume more grass than all the antelope, zebra and buffalo.

Just like mammalian herbivores,

they too have their predators.

A jumping spider.

He’s tiny, less than 3/8 of an inch long,

but he’s a ferocious hunter.

His big, forward-facing eyes give him binocular vision,

enabling him to stalk prey like lions do.

But for his size,

his pounce is much more impressive than a big cat’s.

He can jump several times his own body length from a standing start.

A second species of termite avoids these diurnal dangers by staying indoors.

They build huge castles of mud and saliva

that can be 17 feet high.

A million individuals can live inside.

Their network of tunnels aerates the soil

and their feeding activity keeps nutrients cycling through the savannah.

This secret army of subterranean gardeners is almost never seen.

(THUNDER RUMBLING)

Until now.

After six months of drought,

the first rains trigger an extraordinary response from termites.

They emerge in their thousands and take to the air.

They grow wings just for one purpose,

to breed.

Termites all over the bush emerge in synchrony for this nuptial flight.

It’s their only chance to mix with different colonies and stir up the gene pool.

When they find a willing mate,

pairs drop to the ground together,

where they shed their wings.

Couples follow each other faithfully,

sticking to each other like glue.

The lucky ones will find a cosy corner to mate in

and a new colony will begin.

But up to 90% of these romantic hopefuls will die in the attempt.

It seems an extravagant strategy,

but for the termites it’s a game of numbers.

The more contestants there are,

the more likely it is you’ll get a winner from your colony

passing on his or her genes.

Come morning, the termites’ night of passion is forgotten.

But even after death,

these insects have a last crucial connection in the African bush.

For a hungry vervet monkey, it’s a feast.

She stuffs her cheek pouches.

Each termite is nearly 40% protein.

A few handfuls are a good meal.

The termites are miniature herbivores

that are just as vital a link in the wild web

as antelope and buffalo,

converting plant matter into meat.

From elephants to beetles,

lions to butterflies and baboons to tamarind seeds,

this complex network of hundreds of little connections

is what makes this magical ecosystem work.

Fueled by the sun,

and kept running by an incredible diversity of animals and plants,

the Luangwa Valley is one of the greatest wildernesses in Africa.

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