Original subtitles

Narrator: Africa...

Home to an astonishing diversity of wildlife.

It is a continent with a plethora of landscapes

And creatures.

Including a small, fascinating character

That has formed relationships

With some of the world's largest land animals.

In ancient egypt it was even considered

To be a god that rolled the sun across the sky.

The industrious dung beetle lives in a world

Fraught with challenges.

Moving virtual mountains in its quest to feed and breed.

Vital to the renewal of the land,

It is nature's ultimate recycler.

The african dung beetle story

Starts on the great savanna plains.

Animals thrive here thanks to an abundance

Of grasses and trees, food for many hungry herbivores.

These in turn feed the apex predators.

This is the age-old cycle of life on africa's grasslands,

But there is more to this story than meets the eye.

This ecosystem also depends on the tireless efforts

Of a tribe of little-known insects:

Dung beetles.

Creatures that harness the hidden power of animal waste

And close the nutrient loop

Of one of the world's greatest food chains.

They don't only eat dung,

Their whole lives revolve around it.

Dung beetles exist on every continent except antarctica.

But as the continent richest in large mammals,

Africa is dung beetle heaven.

Here, on a single dung heap

Almost 16,000 beetles from up to 150 different species

Have been recorded.

Scientists estimate that on the african savanna,

Dung beetles clear up and consume about one ton

Of dung per 2-1/2 acres every year.

It's not glamorous, but in nature,

One creature's waste is another's bounty.

This tireless army ensures that the energy driving life

Is ultimately recycled back into the system.

The african savanna is home to many iconic animals.

There are plant eaters here of all shapes and sizes...

From 16-foot-tall giraffes who browse the canopy

To impala who graze the low level.

But the tough, fibrous cellulose in plants

Makes them a challenge to digest.

Animals have evolved different methods to tackle this problem.

Rhino and zebra host an assortment of helpful gut flora,

While ruminants digest in multiple stages.

Ruminant animals, like the kudu,

Have evolved to get the maximum amount of goodness

From their leafy food.

They do this by chewing the cud.

Like domestic cattle and sheep,

Almost all ruminants have four-chambered stomachs.

After food is swallowed, it is softened in the first chamber...

Regurgitated and chewed again

To further break down the tough leaves.

It then passes on to the kudu's remaining three stomach chambers

For digestion.

But despite this processing power,

Some nutrients pass through the gut unused.

Which is where the dung beetle comes in,

Waiting patiently for his payload.

African dung beetles are reliant, in particular,

On one very special animal: Elephants.

Elephants live in family groups of related adult females

And their youngsters, led by a matriarch.

Juvenile males will mature into bulls

Weighing as much as five tons.

Such huge animals need a lot of energy

And spend two-thirds of the day feeding.

And they've got all the right implements.

Dexterous trunks are delicate enough to shell a peanut,

But strong enough to lift up to 770 pounds.

Tusks are used to scrape bark from trees

Or dig bulbs from beneath the ground.

Elephants have the most varied diet of any herbivore.

Their massive molars grind back and forth,

Breaking down even the toughest plant material.

But despite this, they have notoriously bad digestion.

Unlike the kudu, the elephant chews its food only once

And, like us, has only one stomach.

It takes up to 46 hours for food to pass

Through the elephant's system,

And less than half of what it eats is properly digested.

This means a lot of waste.

An adult bull can produce up to 50 tons

Of nutrient-rich dung in one year.

While a whole herd of females makes hundreds of tons.

Food on an epic scale for the dung beetle.

Attracted to the fresh pile by chemical signals,

The beetles rush in.

It may not seem like a feast, but for these beetles

It's a taste acquired through evolution.

Dung beetles have a long history of cleaning up the planet.

They belong to an ancient order of insects, the coleoptera,

Or beetles, which make up almost a quarter of all species

In the animal kingdom.

There are thought to be more than 350,000 different species,

And their diversity is staggering.

From the "tok-tokkies," named for the drumming sound they make

By knocking their undersides on the ground,

To the long-horned beetles,

Named for their elongated antennae,

And the bizarre giraffe-necked weevil of madagascar,

That uses its strange articulated neck for fighting.

Beetles come in all shapes and sizes,

And they have varied eating habits.

The ladybug is actually a predatory beetle.

It will hunt for its favorite meal, aphids,

Often found congregating on a piece of grass.

Another accomplished hunter is the velvet ground beetle.

With long legs for fast running and large, powerful mandibles,

It is a formidable predator.

While some take on the challenge of hunting,

Others wait for food to fall from above.

The first dung eaters may have originated millions of years ago

From ancestors who fed on decomposing plants.

As plants rot, they produce a nutrient-rich, juicy substance.

To utilize this resource, some ancient beetles

Developed filtering mouthparts,

Replacing the biting and chewing mandibles of their forefathers.

These mandibles were later adapted

To extract the nutrient-rich liquids from animal dung.

Fossil evidence suggests beetles were tucking into dinosaur dung

As early as the jurassic period.

But it was the evolution of mammals

And the waste they produced that created the opportunities

For dung beetles to diversify.

Now there are more than 7,000 species

Of dung beetle worldwide--

A remarkable number, considering there are only

Around 5,000 species of mammals recorded.

And they don't just operate during the day.

Many savanna herbivores continue to feed throughout the night.

(bird calling)

With fresh dung being produced after hours,

Many species of dung beetle operate the night shift.

(bird calling)

Dung is never in short supply,

But the beetles are seldom alone.

Competition is fierce.

Epic battles are common.

To a small beetle,

A pile of dung is a colossal supply of food.

But only if it can hang on to it.

Species like this copper dung beetle are known as "rollers."

They are experts at smoothing the fibrous dung

Into a perfectly round ball so they can simply roll it away.

But they need to be quick.

There are thieves about.

Like most contests in nature, size matters.

Larger animals often come out on top.

But being big isn't everything in beetle wrestling.

Another factor can play a role: Temperature.

Beetles are ectothermic;

Their body temperatures are determined by their environment.

But many beetles can also warm themselves through flight.

Warmer equals quicker.

And the quicker beetle is more likely to win the fight.

These two look evenly matched.

But the challenger is kept at bay.

He keeps coming back.

Suddenly the defender is thrown off.

Finally, a compromise.

The ball splits conveniently in half,

Each contestant getting his share.

Dung is highly prized because, to a beetle,

It is more than just food.

It is the foundation on which they build their entire lives.

Like many of the savanna's creatures,

Dung beetles live seasonal lives,

In sync with the continuous cycle of wet and dry periods.

After the cool, dry winter, all the animals are hungry.

With no rain, the grasses dry out and wither.

Unable to function in the low temperatures,

The dung beetles spend this time in a state of torpor,

Sheltering underground.

But as summer arrives,

So too do the first rains.

Bringing a flush of fresh leaves and grass.

This signals the start of the good times for the herbivores,

Which relish the chance to fatten up.

The elephant herds take advantage of green grasses,

Relying less on tough bark and wood.

And a more nutritious diet means top-quality dung.

With the rise in temperatures,

The beetles emerge to join the feeding frenzy.

After such a long slumber,

The beetles need to find food quickly if they are to survive.

And the fresh dung is like manna from heaven.

But it's more than just dinner.

Dung beetles rely on it for another reason.

They lay their eggs in it, creating nests,

Known as brood balls.

Here the larvae can feed on a stash of food big enough

To last them until they emerge as fully grown beetles.

Different beetles adopt a variety of breeding strategies,

Roughly divided into three groups:

Tunnelers...

Rollers...

And dwellers.

The dwellers like an easy life and lay their eggs

In the center of the dung heap itself.

But dung heaps don't last long

With tunnelers and rollers around.

Meaning that dwellers are the rarest

Of southern african dung beetles.

The tunnelers work harder.

They dig nesting burrows right beside or below the heap

That they stock with the choicest dung,

Giving their offspring a great start in life.

This is the most common strategy

Among southern african dung beetles,

Especially in areas with sandy soil,

Where digging tunnels requires less energy.

But even loose sand takes some shifting.

So this beetle has broad, strong forelegs

Specially designed for the purpose.

As ever, the rollers do it the hard way,

Undertaking the formidable challenge of moving

What must seem to a beetle like a mountain.

There are more rollers than dwellers,

But fewer than the tunnelers.

This beetle has found the perfect material

To support her developing larvae.

She begins to shape it into a brood ball

So she can transport it to a suitable place for burial.

With well-developed forelegs, perfectly designed for the task,

The shaping is surprisingly fast.

But the rolling is easier said than done.

The dense ball is cumbersome,

And it takes huge strength to maneuver it

Over the many obstacles en route.

Some rollers can push balls more than 70 times their own weight.

At times like these,

Dung beetles show they're determined characters.

Her efforts will not be in vain.

Removing the ball from the activity at the heap

Is the best way to ensure its safety.

She has found the ideal location to bury her precious cargo.

Once it is underground, she will lay her eggs

Inside the nutritious ball,

Providing a perfect start for her offspring.

Dung beetles don't rely on brute force alone.

They have evolved other ingenious techniques

For dung management.

Gymnastic moves can help.

Using their front legs to push and their back legs to roll,

They can move at an impressive pace.

This speed is crucial to avoid hijackers,

And the quickest path away from competition

Is in a straight line.

They have a clever little trick to help them stay on track.

The navigation "dance" gives the beetle

A raised vantage point and a 360-degree view

Of its surroundings.

This allows it to orient itself using the position of the sun

And head consistently in the same direction

Away from the dung pile.

But obstacles can be disorienting.

So it's up onto the ball for a quick dance to get its bearings.

Amazingly, many nocturnal rollers

Will perform the same dance in the darkness,

Navigating by the milky way

In lieu of the sun.

Apart from humans and migratory birds,

They are the only terrestrial animals known

To use the stars for finding their way.

On hot days, temperatures on the african savanna

Can soar over 100 degrees fahrenheit.

Many animals seek shade to escape the worst of the heat.

But not the ever-industrious dung beetle,

Who keeps working through the hottest part of the day.

The sand is baking, burning the beetle's feet.

Luckily the ball is several degrees cooler

Than the scorched ground and provides an island of respite.

It takes just ten seconds for the beetle's feet to cool

By around 44 degrees fahrenheit so it can keep going.

But for some species, this technique is not enough.

They have had to make a drastic sacrifice

To counteract the dangers of overheating.

This powerful roller is one of the few dung beetles

That can't fly.

It lives in addo elephant national park

On south africa's southern coast.

It feeds on the dung

Of the park's booming elephant population.

But when it comes to nesting, only buffalo dung will do.

The buffalo is one of the largest herbivores in africa.

Renowned for its short temper,

It is less well known for its significant ecological role.

Unlike some more selective grazers,

It prefers quantity over quality.

A prehensile tongue gathers bunches of long grass,

Cropped by a wide row of incisors.

This opens areas of grassland,

Creating access to younger, sweeter shoots

For more selective feeders.

The buffalo is a ruminant and only digests

Around two-thirds of what it eats.

This, combined with the lack of woody material in its diet,

Means that buffalo dung is smoother and easier to mold

Than elephant, making it excellent nesting material

For the addo flightless beetle.

But finding dung is a big challenge for this roller,

Because it is one of the only species that cannot fly.

And for such a little creature,

Covering ground on foot is arduous.

But it hasn't lost the ability to fly for nothing.

Addo's climate is arid, and every drop of moisture counts

For those that live here.

This dung beetle has made an evolutionary trade-off,

Exchanging flight for defense against dehydration.

Beetles, like other animals, breathe oxygen,

Producing carbon dioxide as waste.

This must be expelled, and in the process,

Precious moisture is lost.

But this beetle has developed

A remarkable water-saving solution.

The empty space under its shell, where the wings should be,

Forms a specialized storage tank for carbon dioxide,

Which means it only has to "exhale" once every half hour.

An efficient system, preventing dangerous water loss.

The arid environment means conserving moisture is critical

To the beetles' survival.

More so than flight.

With so many herbivores around,

There's always plenty of dung within walking distance.

From their design to their behavior,

Life for these remarkable beetles is dictated by dung.

In early summer, many animals are preparing for mating.

The rains have brought an abundance of new food,

Giving the best chance of survival for a new generation.

Now the savanna becomes a battleground for many,

As males must prove their virility.

For wildebeest, the rut has begun.

Male impala also lock horns.

Ardent courtship often leads to mating.

Even the dung beetles are getting in on the act.

Not all species are as bold, though, and for most,

Mating will happen below ground in the nesting tunnel.

Before this can happen,

The dung ball must be rolled away and buried.

In some species, like these spider dung beetles,

Both the male and female work together

To get the task completed.

And having wrestled the ball cross-country

To an appropriate spot, the pair gets to work burying it.

Once the male's job is done,

The female lays her fertilized egg safely inside it.

A ball of dung may seem like an odd place to start a family,

But it makes a perfect edible nursery.

Some dung beetle parents give their unborn youngsters

A head start with dung digestion.

Like everyone else, dung beetles produce waste,

And theirs contains a strong cocktail of digestive bacteria,

Just what their offspring will need to start out in life.

These microorganisms are passed on when the female defecates

On the dung ball, before laying her egg inside it.

Once the fertilized eggs are provisioned,

The level of parental care involved

Varies greatly between species.

The nocturnal three-horned dung beetle

And the trident dung beetle are both tunnelers

With horn-wielding males.

But while the female three-horned dung beetle

Provides no brood care whatsoever,

The female trident dung beetle stays in the nest

Until her progeny emerge as adults.

(chirping)

(trumpeting)

For some dung beetles,

Parenting is the last job they will ever do.

They live for a single season,

Just long enough to reproduce once.

But others survive for up to three years.

To live long and prosper, they must look after themselves

And feed up in preparation for hibernation.

The dung beetles' activities may be driven by self-interest,

But they do far more than simply continuing their life cycle.

Their waste management has a dramatic impact

On the landscape and the lives of all the animals

That live here.

Not least the elephants.

In the dry season, they rely heavily on trees for food

And while feeding, swallow many seeds.

These seeds are the lucky ones,

More likely to germinate than those which fall

Straight from the tree.

Most pass through the elephant's system unharmed.

And as the industrious beetles bury dung below ground,

They unwittingly plant as many as 95%

Of the seeds in a dung pile.

The dung also contains nutrients like nitrogen,

Essential for productive soil.

It's the perfect compost.

Thanks to the beetles, seeds that might otherwise

Have shriveled end up planted in rich, well-aerated soil...

Giving them the best chance of growing into a new generation

Of trees that will ultimately feed the elephants.

In this partnership between mammals, plants and insects,

The little beetles are unwittingly repaying a favor

To their biggest dung providers.

It's a perfect example of nature's cycle of life.

Dung beetles are not only waste managers and gardeners,

They are also pest controllers.

The rainy season brings swarms of biting insects,

Including the african buffalo fly,

Which makes life miserable

For many of the savanna's large herbivores.

While ox peckers help with stationary pests like ticks,

Flying insects are more difficult to deal with.

But thanks to the dung beetle's relationship with a tiny mite,

The problematic buffalo flies are brought under control.

The mites piggyback on the beetles to access dung piles,

Where they prey on the eggs and larvae of insects,

Like the african buffalo fly.

Dung beetles can reduce the survival rate of fly larvae

From 40% to just six percent.

These beetles do vital jobs in the ecosystem

Like managing pests and clearing waste,

But they don't do it alone.

Another group of hard-working insects

Also have a role to play: Termites.

During the cold winter months,

When the dung beetles are in hibernation,

The termites will take over their niche.

Instead of spreading the dung, like the beetles,

Termites bring it back to their colonies,

Concentrating the nutrients in one place.

This means that the most nutritious grasses

Are often found around termite mounds.

Rhino are the first to take advantage

Of these lush grazing lawns.

Termites aren't the only animals

That share the dung beetle's taste for waste.

Surprisingly, it's not just insects;

Mammals have developed this habit too.

Just like the dung beetle larvae,

This zebra foal also needs help

Kick-starting its digestive system.

The foal will be weaned

From its mother's nutritious milk at around 11 months,

After which it will subsist on a diet of grass.

To gain the gut bacteria it will need

To digest the cellulose-rich material,

The zebra foal will eat small quantities of its mother's dung

In the first 14 weeks of life.

The same is true of many non-ruminant herbivores,

Including rhino and elephant.

The practice of eating dung, known as coprophagy,

Is fairly common in the animal kingdom.

Some animals even rely on dung for essential minerals.

The leopard tortoise carries his armor with him wherever he goes.

But his hard shell needs a lot of calcium to grow,

And he doesn't get enough in his vegetarian diet.

To make up for this lack, he turns to this:

Hyena dung.

The hyena's jaws are so strong they can crush bone,

Resulting in high calcium levels in their dung,

Which turns it white.

Thanks to this dietary supplement,

The leopard tortoise can grow

His armor-plated, calcium-rich shell,

And under its protection he may live up to 100 years.

And the tortoise isn't the only creature

To turn to dung for its minerals.

Even the daintiest insects, like this rayed blue butterfly,

Will feed on the dung of africa's carnivores

To take advantage of its rich sodium content.

In nature's recycling system,

Dung isn't the only commodity.

Where the life of some relies on the death of others,

A carcass is a gruesome but common sight.

This wildebeest fed a whole pride of lions.

Now the insects are dining on the leftovers

From africa's more famous scavengers,

Like hyena and vultures.

Many species, like dung and carrion beetles,

Will feed on the carcasses of herbivores,

Cleaning the bones from head to toe.

The beetles are filling a grizzly niche,

Making use of resources that few other animals will touch,

Recycling the last scraps of energy

From the wildebeest's body.

It is this cycle of nutrients that allows life to flourish

On the african savanna.

After the rains comes a glut of new life.

Timed to take advantage of the summer plenty.

And there's a new generation of dung beetles too,

Emerging to take on the dirty work in a natural system

That couldn't function without them.

There are more species of beetle in the world

Than any other animal...

And few play a role as important as the humble dung beetle.

The tiny counterparts to africa's giant plant eaters.

Bringing balance to a system

That supports life like no other.

These iconic insects are truly the unsung heroes of africa.

Captioned by media access group at wgbh, access.Wgbh.Org