Seven Worlds, One Planet

At the southern tip of South America,

the Andes mountains rise almost vertically.

Their very height affects life throughout the continent.

The barren slopes look inhospitable.

But like all parts of South America, they're actually rich with wildlife.

A family of puma.

They live further south than any other kind of cat on Earth.

These cubs are only six months old -

entirely dependent on their mother for food.

She knows how to exploit this rugged landscape to her advantage.

And she has to do so,

if she is to catch the continent's most challenging prey.

Guanaco - a relative of the camel.

Two metres tall and over three times the weight of a puma.

The mother's only hope is to go for the throat and try to suffocate her prey.

BLEATS

Her cubs try to help...

...but they themselves don't yet have the skills or the weight

to bring down such large prey.

And the mother is now badly injured.

Her wounds are severe and will take weeks to heal properly.

But without food, her cubs won't survive for long.

The weather in the Andes is harsh and unpredictable.

Snow makes the camouflage on which she relies much less effective.

But she must have food.

The guanaco have left her normal hunting ground...

...and are now in the territory of a much larger male puma.

He's just made a kill, but he isn't about to share it with her.

To hunt here, she'll need to leave her cubs behind

in the safety of their home territory.

Almost invisible in the shadows, she's nearly within pouncing distance.

GUANACO BLEATS

Another failure.

She's got her speed back.

Now she must hold on.

But she is in the male's territory, so her prize isn't safe...

...and her hungry cubs are over kilometre away.

In her weakened state, she will need all her reserves of energy

to drag it back onto her territory.

Only her determination to feed her young keeps her going.

Nearly there.

GROWLS

This one meal will barely last the whole family for more than a few days.

Then their mother - somehow - will have to summon the strength to hunt again.

Life for a hunter in this land is as hard as it gets.

The Andes themselves were built by forces deep in the Earth's crust.

In this part of the Pacific,

the ocean floor has been moving eastwards for millions of years.

Where the sediments meet the edge of the continent,

they're pushed together and forced upwards.

This pressure creates fractures up which molten rock rises

and is then spewed out as ash and lava from great volcanoes.

Nearly 200 of them stretch in a line along the length of the continent.

Some erupt with the force of an atomic bomb every ten seconds.

As the collision continues, the sea floor is dragged downwards,

creating a deep trench just offshore.

Rich, cold waters rise up from it.

And this upwelling creates an abundance of life.

Here, on the coast of Peru,

there are so many seabirds fishing in the offshore waters

that the cliffs are covered in droppings over a metre thick.

Humboldt penguins regard the soft guano

as a good material in which to dig their nest holes.

But it's a messy business.

It's the breeding season, and more hopeful nesters arrive,

spotless from swimming in the sea.

Time for the residents to get cleaned up and catch some fish

for themselves and their chicks.

To get to the sea, they cross the remains of an old nesting ground.

Only 100 metres to go.

But the beach is already crowded with sea lions.

They too have come ashore to raise their young.

And they don't like being disturbed.

SEA LION BARKS

SEA LION GROWLS

To get through such a minefield needs a bold and courageous leader.

SEA LIONS BARK

A brave start.

A dead end.

Now he's in trouble.

This is going to need a bit of crowd surfing.

SEA LIONS BARK

But now all the sea lions are roused.

Getting through them will be tricky.

SEA LION ROARS

A cleansing bathe in the ocean...

...well worth the effort.

The animals living along the Pacific coast

are cut off from the rest of South America by the Andes.

They form a gigantic barrier, stretching over 6,000km

from Patagonia in the south to Venezuela in the north.

This is the world's longest mountain range.

Some peaks are almost 7km high.

They are so tall they catch clouds...

...and so create an environment unlike any other on the continent.

The cloud forest.

Every high valley here has its own unique plants and animals.

One of them is the aptly named Pinocchio lizard.

It was first recorded here 50 years ago and then lost.

It's only recently been rediscovered.

Up here lives a creature so rare that it's seldom seen,

even by those scientists who have come here to study it.

The Andean bear.

Only a few thousand remain.

They eat mostly leaves and fruit,

often clambering up to the very top of the canopy to do so.

He's looking for a type of miniature avocado...

...30 metres up.

The only fruit remaining here is out on the thinnest branches -

too thin to support the weight of a bear.

A more experienced bear has turned up and wants a go.

GROWLS

Time for young ones to watch and learn how to do it.

The trick is to bite the branch just enough...

...to make it swing down and bring the fruit within reach.

Whoops!

Now there's a race to be first on the ground to claim it.

The moisture needed to create a cloud forest

only occurs above a certain altitude...

...so each peak may now have its own species.

In Venezuela, there are similar small worlds,

created not by rain, but by rock.

A great layer of sandstone once covered this entire area,

but rivers cut through it.

As the valleys widened, the tablelands became first huge plateaus,

then isolated flat-topped mountains...

...and, eventually, towers and spires.

On the tops of the bigger ones, animals and plants have now become so different

that they can be counted as new species.

There is no higher waterfall in the world...

...than this one.

Angel Falls - almost a kilometre from top to bottom.

The vertical cliffs surrounding many of these mountains

have kept them largely free from human exploitation.

No such barriers have protected the lowlands...

...but a few patches of forest still remain.

One in Colombia is the home of one of the world's rarest monkeys.

Cotton-topped tamarins.

They're critically endangered.

Only a few hundred families remain.

They live largely on fruit

and are particularly fond of tree sap.

This is packed with sugars, so it also attracts insects.

But tamarins like them too -

a little bit of protein to add to their diet.

There used to be over 50,000 species of insect to choose from...

...but as the forest has shrunk around them,

it's becoming more difficult to find the right ones.

CATTLE MOO

South America is changing.

Over 95% of Colombia's lowland forest has now been cleared.

SHOUTING

Farming has taken the biggest share.

This patch of forest is now isolated.

The few tamarin families here

are now cut off from the rest of their species...

...and beyond their boundary lies an alien world.

CATTLE MOO