Original subtitles

South America is a continent of extremes.

It has the world's longest mountain range... the Andes.

In Amazonia, it has the mightiest river

and the greatest expanse of rainforest on the planet.

And the driest desert on earth

the Atacama, lies beside one of the world's richest seas.

South America also contains incredible variety.

Almost no other continent can boast such a wealth of wildlife

living in such a range of different landscapes.

Almost everywhere you go

there's an extraordinary diversity of life.

But how did all these unique worlds come about?

To understand the natural history of South America

we must go back in time back to the age of the dinosaurs.

South America was then part of Gondwana

a massive continent

that also included what are now Africa Australia, India and Antarctica.

This was a world dominated by reptiles.

Descendants of those ancient creatures still live in South America today.

And the forests of southern Chile still have plants

that the dinosaurs would have recognised

tree ferns and the bizarre monkey puzzle tree.

Then, a new group of animals appeared animals like this.

The early mammals were small

and many were marsupials like this shrew opossum.

It lives in the cold damp forests of southern Chile

where it hunts for insects and earthworms.

The shrew opossum shares these ancient forests

with this other small marsupial.

Local people call it the 'monito del monte'

or 'monkey of the mountains'.

It's so tiny you could hold it in the palm of your hand.

It too eats insects but also has a taste for fruit.

When we think of mammals with a pouch

it's perhaps Australia with its kangaroos that comes to mind.

But South America also has over eighty species of marsupial

a legacy of the time

when the two continents were joined together.

Around a hundred million years ago

the giant continent of Gondwana slowly split apart.

South America became an enormous island

cut off from the rest of the world.

The next chapter in South America's history was violent and prolonged.

It changed the face of the continent for ever.

Starting some eighty million years ago

the island was convulsed by a series of massive volcanic eruptions

that continue today.

Forced up by movements deep in the earth's crust

a huge chain of mountains arose

spanning the length of the continent The Andes.

Running over five thousand miles

this is the longest mountain chain on earth.

At its northern end tropical cloudforest covers the slopes

yet its peaks are so high

that even on the equator they carry permanent snow and ice.

In the central Andes

there's a high dry desert the altiplano.

As you travel further south

the mountains are lower

but they're that much closer to the Antarctic.

In the far south

the Patagonian ice sheets are the largest

expanse of ice outside the polar regions.

They cover more than seven thousand square miles

and their glaciers flow all the way to the sea.

But even here

in the shadow of the ice animals survive.

In the shadow of the Patagonian icecap

animals must survive ferocious winds and winters of heavy snow.

Only the hardiest animals can live here

like guanacos South American relatives of the camel

and foxes.

Even for them

surviving the winter is a challenge

Patagonia may be severe

but it's not the most extreme part of the Andes.

That's back in the heart of the range

an oxygen-starved plateau more than four thousand metres high.

Here, in the Altiplano

meltwater from the surrounding peaks evaporates in huge salt lakes.

Frozen by night and baked by day

these caustic saltflats must be

one of the most inhospitable places on earth.

This is Salar Uyuni in the Bolivian Andes.

Covering four and a half thousand square miles

it's the largest expanse of salt on the planet.

Incredibly, islands in this sea of salt actually support life.

Viscachas.

These rabbit-sized rodents have to contend with thin air, bitter cold,

and an almost total lack of water.

They get just enough moisture to survive from their food.

Thick fur keeps them warm

and extra red blood cells help to absorb sufficient oxygen.

The thin air's a problem for this hummingbird too.

To conserve energy when it's feeding it has to perch, rather than hover.

The high altiplano may seem hostile

but some animals actually choose to come here.

Flamingos come here to breed

because these caustic waters are full of their favourite food.

They display to each other with a massed courtship dance.

The rise of the Andes created

whole new environments within the mountains

but it also had more far-reaching effects.

This great barrier changed the climate of South America.

It also re-drew the map of the entire continent

radically altering the course of its major rivers.

The Iguazu Falls are one of the wonders of the world.

Four times as wide as Niagara

they carry sixty thousand tons of water a second.

Part of Amazonia was once a huge swamp

connected to the Pacific and the Caribbean.

The rise of the Andes broke those links

forcing the major rivers to flow east.

One massive river now drains forty percent of South America... the Amazon.

This is the mightiest river on earth.

Running over four thousand miles from the Andes to the ocean

it carries a fifth of all the river water on the planet.

A thousand miles before it reaches the sea

its main channel is already ten miles wide.

Every year the mighty Amazon bursts its banks

flooding an area of forest the size of England.

At the height of the flood

the trees can stand in water ten metres deep.

The floodwaters bring with them the animals of the river

like boto dolphins.

Their origins are a mystery.

Could they be a relic of Amazonia's ancient links with the oceans?

These river dolphins are almost blind

no handicap in water that's often very muddy

because they navigate by echolocation.

Unlike marine dolphins they have a flexible neck

so by sweeping their head

from side to side they can scan their path ahead.

Their sonar is so precise that they can weave their way

through a maze of submerged branches in search of fish.

Whisker-like bristles on their lips help them zero in on their target.

The botos' origins may be mysterious

but some of the Amazon's fish certainly have a marine ancestry

like stingrays.

Their nearest living relatives are in the Caribbean.

The Amazon has over three thousand kinds of fish.

This is the pirarucu the world's largest fresh water fish.

And these are the most notorious... piranhas.

The variety of life in these waters is extraordinary...

and with so many fish there are bound to be fish hunters.

In this water world

Caiman are the top of the food chain...

the aquatic equivalent of the jaguar.

Red-bellied piranhas are predators themselves

but to a caiman they're just another mouthful.

The Amazon river and its tributaries

drain the largest expanse of tropical rainforest on earth.

Stretching almost unbroken from the Andes to the Atlantic

the Amazon jungle has a greater variety of life

than any other forest on the planet.

In just over two square miles of forest

scientists have counted three thousand varieties of plants

five hundred and thirty kinds of birds

and eleven different species of monkeys.

There are countless reptiles amphibians and insects.

Six hundred and fifty species of beetle

and eighty kinds of ant have been found on a single tree.

Scientists disagree about the reasons for this diversity

but in almost every group of animals

the number of different species is extraordinary.

Because there are so many species

most of them have to specialise.

Pygmy marmosets are the world's smallest monkey.

They live on the sap of just a few kinds of tree

gouging the bark with special teeth to release its flow.

They're just one of over thirty species of marmoset

and tamarin in the Amazon basin

a group of monkeys unique to the lowland rainforests of South America.

Like these tassel-eared marmosets most live in family groups.

A breeding female lives with one or more adult males

and several youngsters.

Females typically give birth to twins

and unusually among monkeys

it's the father who's left holding the babies.

Tassel-eared marmosets are opportunists.

As well as gum, they eat insects fruit, birds' eggs

small snakes and lizards...

almost anything they can get their hands on.

The youngsters must develop fast

if they're to survive in the dangerous

and competitive world of the rainforest.

Amazonia lies on the eastern side of the Andes

and here torrential tropical rains water the prolific jungle.

But the mountains block the moisture-bearing winds

so some of the western side receives almost no rain.

Here lies the world's driest desert... the Atacama.

The Atacama can go for years with literally no rain at all.

It's hard to imagine how anything could survive here.

And yet it does.

Guanacos.

These South American camels can tolerate extremes of heat and cold.

A desert might seem a better place for a camel

than the snows of Patagonia

but the Atacama is a challenge even for them.

Daytime temperatures can rise to forty degrees.

Their only relief is a dry dustbath.

But what can they live on?

With hardly any water here how could plants possibly grow?

This is the key to survival in the Atacama the Pacific Ocean.

The desert is a narrow strip between the mountains and the sea.

Moist air over the water is chilled

by a cold ocean current just offshore

so every day

a blanket of fog rolls in from the Pacific.

The fog is almost the only source of water in the desert.

Moisture condenses on the cactus spines enough for lichen to grow.

And every morning

the lichen is covered with the precious droplets of water.

This water provides a life-giving drink

for the few hardy inhabitants of the Atacama

like diuca finches.

The guanacos obtain moisture by eating the lichen

delicately extracting it

from between the cactus spines with their soft, sensitive lips.

They also eat the flowers of a parasitic plant

that grows on the cactus.

Called quintral it's sweet and full of nectar.

Guanacos and everything else in this desert

are living on the edge.

Without the moisture from the early morning fog

life in the Atacama would be almost impossible.

As you travel South

the prevailing weather comes from the opposite direction

so the eastern side of the continent is dry.

But here lack of water is not the most extreme problem

it's the wind.

This is the land of the Roaring Forties

ferocious winds that batter the dry grassy steppes of Patagonia.

Anything that lives here has to contend with almost incessant gales.

These are maras large rodents unique to South America.

Adult maras live and give birth to their young in the open

but they rear them in an underground burrow

sheltered from the cold winds and predators like foxes.

Mara territories overlap

so often several pairs share a burrow.

These warrens act as a community creche.

The parents can leave their young to go and feed

but there's always someone to keep an eye on them.

The nursery can have twenty or thirty young.

Sometimes hungry infants try to suckle from the 'baby-sitter'.

She tries to drive them off

but they can steal a tenth of their milk this way.

In windswept Patagonia

a hole in the ground counts as prime real estate

and it's a magnet for squatters.

Here even the birds nest underground.

As soon as the maras backs are turned

burrowing owls try to take over their home.

Could this be the moment to move in?

But they're soon spotted.

This time, the squatters are evicted.

The maras keep their burrow.

In Patagonia

burrowing owls aren't the only birds that nest underground.

With no trees to nest in

burrowing parrots excavate holes in a sandstone cliff.

There can be over fifty thousand birds in these colonies.

This is one of the few places on earth

where parrots nest by the seaside.

The diversity of South American wildlife doesn't end at the coastline.

The seas that surround the continent are some of the richest in the world.

Upwellings of cold, nutrient-rich water feed huge shoals of fish...

food in turn for seabirds and marine mammals.

The sheer numbers of fish here are astounding.

A single shoal of anchovies can be hundreds of thousands strong.

These huge concentrations inevitably attract predators... dusky dolphins.

The dolphins' migrations are synchronised with the anchovies' movements.

For the defenceless anchovies there seems to be safety in numbers.

When they come under attack

they bunch more tightly together...

to form a dizzying ball of swirling fins and scales.

The dolphins find it harder to target any single fish in this dense mass

so they try to break up the shoal...

by swimming through it.

Once the shoal has been split

the dolphins confuse the fish

and scatter them even more by blowing bubbles...

and by emitting high frequency sounds that stun them.

This drives them to the surface

where they become easy prey for seabirds too.

Attracted by the disturbance

yet more hunters join the attack... southern sealions.

Under assault from all sides

the fish are now totally disoriented.

Trapped at the centre of this feeding frenzy

they don't stand a chance.

Magellanic penguins mop up the last survivors.

At the end, all that's left are tiny fish scales...

drifting down into the deep.

For almost a hundred million years South America was an island.

Its animals evolved in isolation

cut off from the rest of the world by the surrounding sea.

But around three million years ago

the same kind of movements of the earth's crust

that built the Andes raised a land bridge joining North and South America.

Animals could now pass easily between the continents.

The impact on South America was profound.

Among the first mammals to arrive were these... coatis.

Relatives of the North American racoons

they're active, agile intelligent and adaptable.

They quickly colonised this land of new opportunities.

Today they're found as far south as Argentina.

These early invaders soon made South America's forests their own.

For the continent's original inhabitants like the sloth

life would never be the same again.

These brash newcomers were just so fast.

Sloths are lethargic by nature as well as by name.

They have a low body temperature and very slow metabolism.

Sloths have hung on by doing one thing supremely well

eating and digesting leaves.

Coatis succeed because they're opportunists

quick to seek out any new snack.

They leave sloths behind at the starting line.

They're social animals living in bands of up

to twenty females and their youngsters.

And they're omnivorous eating fruit

insects, spiders, slugs, fish, snakes birds and mammals...

almost anything they can find.

A flexible nose and a good sense of smell

help them sniff out the slightest chance of a meal.

These early colonists were soon followed by others larger

and more deadly like the jaguar.

South America had large carnivores before cat and dog-like marsupials.

But many had already died out before the newcomers got here.

Coatis may have had it easy when they first arrived

but once large hunters followed life became tougher.

On the whole, the invaders were very successful.

Some may have out-competed the original inhabitants

others may have eaten them

but many of the new animals simply moved into spaces

that were already empty.

Today, almost half of South America's mammal families

are North American in origin.

Eventually the immigrants in this new found land

spread to all corners of the continent.

As the invaders adapted to their new surroundings

some evolved into new forms.

A simple, dog-like ancestor gave rise to this the maned wolf.

Like a fox on stilts

this long-legged predator hunts the grassy plains of southern Brazil.

It eats small animals and must travel far to find enough to eat.

The great plains are one of South America's most ancient landscapes.

Throughout the continent's history

they've remained relatively unchanged.

Today they have a strange mixture of animals the old and the new.

Deer are relatively recent arrivals from North America.

On the plains they rub shoulders with animals

that have been here for tens of millions of years...

Like the rhea

South America's equivalent of the ostrich.

If the maned wolf is one of the most recent animals on the plains

this is one of the oldest

The giant anteater.

It's one of the most specialised insect-eaters on earth

and that bizarre snout is one of its secret weapons.

The snout houses a long sticky tongue

ideal for delving into termite mounds.

But first you've got to break in.

Termite mounds can be almost as hard as concrete

so you also need a set of very powerful claws.

The giant anteater is one of the few surviving members

of a group of animals

that has lived in South America for over fifty million years.

This is another one, the armadillo.

Armadillos and anteaters survived the invasion

because they specialise in food the invaders can't tackle.

They eat mostly ants and termites.

The maned wolf doesn't compete with them because it prefers mice.

But catching them isn't easy.

All that effort for just one tiny mouthful.

The animals of today's South America

are a pale shadow of what was once here two ton armadillos

flesh-eating birds three metres tall

a giant ground-living sloth the size of an elephant.

The ground sloth disappeared less than ten thousand years ago.

What drove these giants to extinction?

Long after the land bridge linked North and South America

there was one last great invasion

the most far-reaching of all.

No one knows exactly when the first people arrived

or even how they came by boat along the coast

or overland from North America.

We do know they've been here for at least twelve thousand years

and they soon penetrated every part of the continent

from the sea coast to the high peaks of the Andes.

The first hunter-gatherers may have hastened

the extinction of creatures like the giant sloth

but they made little direct impact on the landscape.

But the development of settled agriculture

eventually changed the face of South America.

Elaborate civilisations flourished

in the most remote corners of the mountains.

Their last monuments can still be seen high in the Andes

in the ruins of the legendary Inca city of Machu Picchu.

People even changed the animals.

Around seven thousand years ago

they domesticated wild relatives of the guanaco

to produce Ilamas and alpacas.

As sources of meat and wool and beasts of burden

these were the key to survival in the high Andes.

These domestic animals are still important

to the people of the altiplano today

and are an integral part of their culture.

By selectively breeding from their wild ancestors

the mountain people have developed different aspects

of the animals to suit different needs.

Llamas are better pack animals and have good meat

whereas alpacas are more valued for their dense wool.

Llama fairs, and even races

are a high point on the local calendar.

And they're more than just an excuse for a party.

The animals carry weights

so the race is a test of stamina

especially at this high altitude.

Traditional cultures have survived in places like this

because they are so isolated from the outside world.

Wildlife too survives

because much of the continent remains isolated and remote.

People may have irretrievably changed parts of South America

but it's a vast continent

and much of it is too extreme for people to settle.

So it still retains huge areas of stunning wild landscapes.

For sheer variety it's without rival anywhere on earth.

South America's natural landscapes

and their wildlife owe their existence to the continent's unique history.

They're the latest spectacular chapter in a story

that has been unfolding for over a hundred million years.