Original subtitles

Two billion years ago,

a giant meteorite collided with Earth,

releasing enough energy to vaporize solid rock.

A site of total devastation,

its effects rippled throughout Africa.

But over the course of time, life conquered the barren lands.

And today, the crater's past is all but forgotten.

This ancient landscape creates a haven for the unique plants

and animals of the Vredefort Dome.

(♪♪♪)

(♪♪♪)

(♪♪♪)

(♪♪♪)

Lying in the grasslands of Southern Africa's

interior plateau is a little known wonder.

185 miles wide and six miles deep,

the Vredefort crater is an ancient world.

Forged when a giant meteorite collided with earth,

it was one of the largest impacts ever to hit our planet.

The vast mass of rock was thought to have been

six miles in diameter

and traveling at 44,000 miles an hour.

But over the course of time the crater's scars healed

and life not only began to arrive in the desolate lands,

it thrived here.

(♪♪♪)

(♪♪♪)

(♪♪♪)

(♪♪♪)

(♪♪♪)

(♪♪♪)

(♪♪♪)

(♪♪♪)

Signs of the impact are now only visible from space.

At the very center of the collision,

is what is known as the Vredefort Dome.

Mountains of ancient rock lie in rich, fertile grasslands.

Whilst rivers and wetlands provide the water

needed for life to flourish.

Today, the mountains of the Vredefort Dome

are the most prominent feature on the landscape.

Surrounded by seas of undulating grassland,

they hold clues to the crater's past.

Rounded granite boulders

embedded in a black glassy obsidian layer

are the result of colossal forces exerted during the impact

liquefying rock.

These outcrops were once the giant canvas

for some of the world's first artists.

Ancient engravings, left by Bushmen who once sheltered here,

tell of a landscape rich in life.

It is thought the Vredefort crater may have played

an important role in human evolution.

Some even believe that without the major evolutionary changes

the impact caused, we would not be here today.

However the crater links to our past,

we have been drawn to it for shelter, food

and in the search for wealth.

These tunnels were dug by gold prospectors decades ago.

When the meteor struck,

it fractured rock deep beneath

the surface of the Earth,

pushing South Africa's gold reserves deep underground.

Here the gold was preserved from erosion,

laying the foundation for South Africa

to become the world's biggest exporter of the precious metal.

Abandoned as unproductive, these tunnels now offer shelter.

Horseshoe bats have taken up residence.

Hunting on the wing,

they consume flying insects from the night sky.

And they are not the only ones making the most

of the tunnels' refuge.

Cave toads also shelter in the darkness.

From the very base of the mountains, life is provided for.

The Vredefort crater's unique mix of landscapes and vegetation

make it a special place for wildlife.

Grasslands dominate South Africa's high interior plateau.

It is here that the mountains of ancient rock form islands,

rich in species not normally found on the open plains.

Higher up the mountainside

a pair of Mocking cliff chats are calling.

The territorial birds defend sections of the rocky hillside.

And this pair have a reason to be protective...

they have a couple of new arrivals.

Their recently fledged chicks are getting a feel for life

outside the nest.

The rising hills provide shelter for flowering plants

and trees to grow,

attracting a new cast of creatures.

From Long-horned beetles...

to kudu.

These majestic antelope are browsers,

feeding on trees and bushes.

Rarely found out on the open grasslands,

they are drawn here by food.

And they are not the only ones tempted away

from the plains below.

At over 16 feet tall, giraffes have the pick of the canopy.

Being able to eat from all levels of the tree

gives them a valuable edge when conditions are poor.

The mountain vegetation provides food for the largest

and for the smallest of creatures.

Chafer beetles feed, moving from flower to flower.

Along the way they transfer pollen,

pollinating the plants in the process.

It's a win-win scenario for both the beetles and the flowers.

But the chafers are looking for a bigger meal...

and around here, they don't need to go far.

The flowers of the Sugar Bush Protea

are famed for their abundant, sweet nectar.

And the chafers seem to agree.

This plant is more than just a source of food

for the local insects;

it is part of a unique relationship.

Growing out of the rough-barked stems is a parasitic mistletoe.

It grows directly from the sugar bush,

taking the nutrients it needs from its host.

But the mistletoe is itself a host plant.

The caterpillar of the Sapphire butterfly

lives only on the leaves of the protea mistletoe,

feeding off it until it is ready to begin the next stage

of its metamorphosis.

Over the next two to three weeks

this lowly caterpillar will transform

into a Sapphire butterfly.

For this butterfly the protea mistletoe is everything.

Without it, it would not survive.

The Sapphire butterfly exists here in the Vredefort Dome

due to a specific set of conditions,

which would not have come about

had the meteorite not struck all those years ago.

Over 100 species of butterfly now live

in its 115 square miles.

More than double the number found in the whole

of the United Kingdom.

And they're not only here for the host plants.

In sexual selection, many butterflies resort to a behavior

known as "hilltopping".

Males fly to the highest point of the mountain

and occupy a prominent perch until a female appears.

When she does, the males take off in a courting flurry.

Flying to the very tops of hills

demonstrates their physical prowess.

And therefore their strength as a mate.

These mountains provide food,

shelter and opportunities for a range of animals

perfectly adapted to their unique ecosystem.

Cutting through the Vredefort crater

is one of South Africa's largest rivers.

A vital water source, the Vaal winds its way

through more than six hundred miles of the country

on its westward journey toward the Atlantic ocean.

Its route courses straight through the crater,

providing habitats for a range of life.

Sacred Ibises are early risers,

making the most of what the river has to offer.

The flock probes the mud searching for crabs, worms,

frogs and anything else they can find.

Later in the day, they'll head to the grasslands to hunt.

The river is a magnet for bird life of all kinds.

From wagtails, to Yellow-billed ducks.

A Nile monitor enjoys the morning sun.

At three feet in length it is only half the size

it will eventually reach.

Cold blooded, the reptile needs the sun's heat to warm its blood

before it can start to hunt.

Once fully charged, it heads off in search of breakfast.

With predators about, this White-browed sparrow-weaver

is taking no chances.

He's building his nests high up in the branches of a thorn tree.

In a land covered with grass,

supplies should be easy to come by.

But this weaver only uses the best--

he's using it to attract a mate.

Two entrances allow the weaver to make a swift getaway

should a predator find the nest.

However, once he has found a mate

and she has laid her eggs

he will have to seal the back door for protection.

A male Red Bishop is also showing off.

But he doesn't only rely on his DIY skills.

During the breeding season his feathers turn bright red

to attract females.

If he's successful he'll mate with as many

as eight in a season.

Throughout the day many other species are drawn to the water.

But not all are in search of sustenance.

Damselflies use stagnant pools to mate.

The male uses special grasping clips on his tail

to hold the female often for more than an hour.

His clips fit into neat depressions behind her head,

locking tight.

Each species has a unique lock and key.

Even once the pair has mated, the male's job is not done.

The female begins laying her eggs

and the male retains his vice-like grip.

If he leaves, other males will remove his sperm

and mate with her,

so he remains with his partner

until she has finished laying.

These waters support many different life forms.

The Goliath heron is the largest heron species

and requires a lot of food.

Despite this they are selective hunters,

spending as much as 75% of their time

standing completely still,

waiting for just the right size prey to cross their path.

Under a hot African sun

the birds can't sweat to cool down.

To solve the problem they have developed a technique

called "gular fluttering"

similar to the panting of dogs.

By rapidly moving air through a pouch in their throats,

which has a rich blood supply,

they are able to cool their bodies.

The Vaal is a crucial feature in the Vredefort landscape,

providing water that is so vital for supporting life.

From here, it flows westward

on its long lonely journey to the sea,

striking out across the Highveld grasslands.

In the summer months the grasslands

on the outskirts of the Vredefort crater come alive.

The rains have come and new life is everywhere.

The open grassy plains, which have lain dormant

all through the dry cold winter, have rebounded.

And the animals have a new spring in their step.

At first glance these grasslands may look flat and uniform.

But they harbor a unique variety of life.

A Long-tailed widowbird is looking for a mate.

Dragging his enormous tail behind him,

he is showing off with a display of strength.

Males are territorial.

And they perch on prominent vegetation

to advertise their presence.

Before taking to the wing to perform.

Their tail feathers can be up to forty inches long

and drag below them as they patrol their territory.

While his tail is cumbersome his efforts are likely to pay off.

If successful, he will mate with as many as five females

during the season.

These grasslands support the weird...

and the wonderful.

The white rhino is the largest grazer on the planet

and the biggest animal ever to have existed

solely on a diet of grass.

The short, sweet, nutrient-rich blades of the summer

are a welcome treat.

Across the plains animals are making the most

of the flush of life.

Secretary birds use their legs as weapons,

stamping larger prey species,

including venomous snakes, to death.

And this pair are busier than usual.

With two hungry mouths to feed they have their work cut out.

A family of Ground squirrels keeps a wary eye

on the Secretary birds.

Their pups could be prime targets for the predators.

Luckily for the chicks,

their arrival coincides with the explosion of new life.

For the rhino mother and calf,

the grasslands pose little danger.

In the natural world adults are practically invincible.

They have sharp horns and thick armored skin

too tough for most predators.

But calves are more vulnerable so mothers keep them close

until they are big enough to fend for themselves.

For smaller species

the open spaces of the grasslands are a problem.

Out here, they are exposed to predators.

Ground squirrels have adapted to the dangers of the grassland

by building their warrens underground.

But when there aren't any predators about,

they come to the surface.

Extremely sociable animals

they live in large groups of up to 19 individuals.

As a result, socializing is an important daily activity.

Males live separately and will only visit

when the females are ready to mate.

For the rest of the time, groups of dominant females

live together with up to nine sub-adults

and the females' dependent offspring.

When food is abundant and there aren't predators around,

family life is relaxed.

Another unique burrower has chosen a life

below ground on these grassy plains.

A Giant girdled lizard, known locally as a Sungazer.

Burrowing makes them unusual.

They are the only girdled lizards to do so.

All the other species live in or on rocks.

But here, in the open grasslands

suitable rock homes are not common.

So if a predator attacks it dives underground.

Nearby, an Amur falcon is on the hunt.

But part of life on the grassland

is knowing what's a threat and what's not -

and this Amur falcon subsists almost entirely on beetles,

locusts and other, smaller insects.

These thrive in the grasslands, meaning that prey is plentiful,

competition for resources is minimal

and these falcons can exist here in remarkably high densities.

For the pair of Secretary birds life is tougher.

They need bigger prey and far more of it.

The chicks are increasingly hungry.

But it will be another two months before they stride out

onto the grasslands for themselves

and life returns to normal.

For all animals, finding food is an essential part of life.

One group has developed a unique way

of getting their daily nourishment.

After rain, butterflies congregate around puddles

on the ground.

Once they have drunk their fill, something surprising happens.

They begin to excrete liquid.

This method allows the butterflies to filter the water,

absorbing important nutrients without having to store

all the fluid.

A variety of insects obtain the moisture and nutrients they need

in this way.

Where there are lots of butterflies

there are lots of caterpillars.

And from the very first day these are under threat.

To compensate, caterpillars have developed many strategies

to prevent themselves being eaten.

Some hide away, whilst others fight back.

They grow long, fibrous hairs that deal a nasty sting

to anything that disturbs them.

Others rely on their host plants for protection.

The Spotted joker feeds on stinging nettles,

which deter predators.

Monarch butterflies have taken toxic warfare to a new level.

Their caterpillars retain toxins from their host plant

in their body tissue during metamorphosis.

And adult butterflies emerge as unpalatable as the caterpillars.

This has been so successful for the Monarchs,

other butterflies have mimicked them.

Not poisonous themselves

predators avoid them, thinking they are.

Throughout the natural world,

the predator-prey dynamic drives evolution.

A family of Meerkats is on the lookout.

Meerkats live in close family groups

comprising a dominant female and her mate

and many generations of offspring.

In times of plenty, groups can number

as many as 30 individuals.

The larger the family, the more eyes to spot predators.

At the first sign of danger,

they disappear into the safety of their burrow.

But occasionally, they decide to fight back.

Even if the towering ostrich doesn't pose any sort of threat.

Dotted throughout the Vredefort crater's grasslands

are wetlands and pans.

The availability of permanent water attracts animals

from all around.

Where there is water, there is always life.

Common plantaina frogs feast on insects above the surface.

With pockets of life dotted throughout the crater,

in its mountains, rivers and wetlands,

animals gather in their greatest numbers on the grasslands.

The plains are home to the grazers.

Black wildebeest live in mixed herds of females and youngsters,

moving through the territories of adult males.

During the mating season,

males corral females on their territory into harems.

And will defend their right to mate with them all.

But they have a job on their hands keeping them all in check.

Black wildebeest were brought to the brink of extinction

during the 19th century.

Between 1870 and 1871 alone,

the skins of nearly half a million black wildebeest,

blesbuck and zebra were exported from the coastal port of Durban.

Before the scourge of hunting, these three species dominated

South Africa's high grasslands along with springbok.

Moving in herds of thousands.

Today, they only exist in fragmented pockets

isolated among miles and miles of farmland.

Despite the apparent abundance of food,

much of this tall grass is fibrous and of little value.

The animals that live on these plants have developed

a number of ways to cope with this low-quality fodder.

Blesbuck are pure grazers.

They eat selectively, consuming only grasses that provide them

with the nutrients they need.

Springbok complement their grass diet with a range of succulents,

herbs, and shrubs in order to survive.

And another resourceful herbivore is the buffalo.

They are predominantly grazers,

eating a large variety of grasses.

Buffalo will chew, swallow, regurgitate

and continue to chew, in order to break down

the high cellulose content of their food.

Ensuring they get the most out of their meal.

Zebra and wildebeest often occur together

because there is little competition between them.

Zebra have evolved a digestive system adept

at removing nutrients and protein from fibrous grasses.

They often clear the way to shorter, sweeter grasses

for the wildebeest.

On these grasslands animals have found a niche for themselves

allowing them all to happily coexist side-by-side.

But it's not always peaceful.

Two male giraffes are battling for the right to rule.

The hard bony heads can inflict serious damage.

Fights can go on for hours before a winner finally emerges.

A drawback faced by all animals on the open grasslands

is that there is nowhere to hide.

Living side-by-side benefits some through safety in numbers.

But they are all built for speed.

In large open spaces such as this

their first instinct when startled

is to break and run.

But predators have long disappeared from the crater.

And it is only an evolutionary impulse

that drives them to flee.

This strategy is in stark contrast to that employed

by the bulkier buffalo.

These are built for power.

If threatened, the herd rarely breaks and runs.

Both bulls and cows have formidable horns.

While cows use their horns predominantly for protection...

bulls use theirs in fights

to establish dominance with the herd.

Which are strictly hierarchical with dominant individuals

winning the right to occupy the center of the gathering.

Inferiors hang on the fringes

where they are more exposed to threats.

For both of these old timers

a life of solitude is full of danger.

The grasslands support many giants.

Including the largest antelope in the world - Eland.

Contests for dominance here are usually settled

without coming to blows.

Status is determined by a range of clear visual signals,

including the size of the dewlap -

the fleshy skin below the throat.

Mature males will also rub the furry patch on their foreheads

in dirt and urine, turning it into a smelly, caked mass.

This strong odor is associated with strength and dominance.

Like many of the animals out on the plains,

eland have not lost their instinct to flee.

They will dash for safety, but unlike the smaller antelope,

they haven't evolved for speed and quickly tire.

Instead, they turn to stand their ground

against the perceived threat.

Grouping around in defense of their young.

Protecting your family is a daily struggle

for many of the grassland residents.

Male Red hartebeest establish territories

to protect their females and offspring.

Excellent eyesight helps them spot both intruders

and potential predators.

Herds are strictly organized.

Females establish a dominance hierarchy

and youngsters remain with their mothers

for up to two and a half years.

The vast numbers of grazers

draw in even larger numbers of insects.

Which swarm during the rainy season.

Even the toughest suffer.

Zebra use their long tails as much as anything else,

but they have another ingenious advantage--

their famous stripes.

Blood sucking flies locate their hosts by sight

and are attracted to large areas of a single tone.

The zebra's stripes make it harder to home in on,

and they suffer less from bites as a result.

Flies are not the only bloodsuckers around.

Ticks thrive.

Without the benefit of wings, they sit on the ends of grasses,

waiting for a host to pass by,

climbing on when they get the chance.

In a delicate arms race,

animals living on these grasslands

are relatively immune to diseases

carried by these parasites.

One such host is baboons.

These primates have two advantages

when it comes to parasite control.

Cooperation and opposable thumbs -

which are both essential for grooming -

an important way of maintaining social cohesion.

And it also helps rid yourself of ticks.

Millions of years ago

another slightly more sophisticated primate

came down from the trees and strode out

onto the grasslands of Southern Africa.

Drawn perhaps by the wide open spaces to hunt

and new territory to claim.

The lands covering the Vredefort crater

contain a fascinating array of animals

both big and small.

It is not a uniform world.

But one of intricate details and unique exceptions.

From tiny caterpillars, to mighty rivers...

life occurs in abundance.

A reminder that every species survives

in a fabric of time and space

stretching back to the very beginning.

(♪♪♪)

(♪♪♪)