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This is a journey down
the longest mountain chain on earth.

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These are the Andes
the spine of South America.

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They span the length of the continent
over five thousand miles

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00:01:03,496 --> 00:01:06,522
from the tropics
almost to the Antarctic.

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Surviving in the Andes is one of the
greatest challenges in the natural world.

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It's a truly hostile place to live
bitter cold, thin air, relentless wind

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...even the volcanic forces of
the earth itself.

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Faced with trials like these

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how can anything survive here
let alone flourish?

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Our journey begins in the tropics
at the northern end of the range.

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The highest peaks in the Andes rise to
nearly seven thousand metres.

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And some are still growing.

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Measured on the scale
of geological time

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the Andes are still young.

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The mountains mark a line

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where two great
plates of the earth's crust collide.

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The impact crumples the continent
and huge volcanoes break through.

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As the mountains rise into the clouds

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their slopes are colonised
by forest

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cloud forest.

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In the warmth of the tropics
trees can grow high on the mountains

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to well over three
and a half thousand metres.

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Animals were quick to exploit the new
opportunities these forests provide.

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Isolated in a maze of ridges and valleys
all sorts of new species developed.

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These Andean cloud forests rival
the Amazon rainforest for diversity.

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There are more kinds of hummingbird here
than anywhere else in the world.

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Almost every hillside has its own
unique plants and animals.

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The cloud forest also
has its very own bear

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the spectacled bear
named after the markings on its face

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This is the only bear in South America.

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There are just a few thousand left.

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Most kinds of bear are good tree climbers

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but here that skill is essential.

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Spectacled bears get much of their food
from the treetops

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so climbing trees is one of the first
lessons this baby has to learn.

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The cub is well grown

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but it still has a long way to go to
match its mother's skills.

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The trees here can be twenty metres high

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so it can't afford to make a mistake.

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These high forests have few monkeys

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so there's plenty of food for bears
that are willing to climb.

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But for an animal that can weigh well
over a hundred kilos

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that's quite a challenge.

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Even when it's mastered
the art of climbing

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the cub still has to learn
what to eat.

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The bears' favourite food
are bromeliads

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plants that perch on branches high
in the canopy.

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They're especially fond of
the fleshy base of the leaves.

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Bears are adaptable animals
and there's only one kind here.

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Other animals are more specialised

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so several species can coexist
like the hummingbirds.

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These damp cool forests
have few flying insects

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so many of the flowers rely on birds
for pollination.

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Plant and pollinator
have a unique relationship.

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Each hummingbird's beak is perfectly

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adapted to reach the nectar
in its chosen flower.

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As the hummingbird moves
from flower to flower

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it transfers pollen
and so fertilises them.

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In exchange

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it gets sugar-rich nectar
to fuel its hovering flight.

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At high altitude, the air is thinner
and has less oxygen.

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It's hard to hover.

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Most bromeliads win their place in the sun
by growing high in the trees.

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But some kinds have gone a step further.

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They've left the forest behind
and climbed the mountain.

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The puyas grow in the paramo

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a zone of alpine grassland
above the forest.

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After several years

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they throw up a stupendous five metre
flower spike... and then die.

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With just a once
in a lifetime opportunity

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it's vital
that the flowers are pollinated.

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Puyas have their very own hummingbirds

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like the Andean Hillstar.

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It lives higher
than any other hummingbird.

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Up here the air is even thinner
and hovering is even harder.

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So whenever it can
it perches rather than flies.

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As it moves from flower to flower
it transfers more than pollen.

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Tiny pollen-eating mites
live in the flowers.

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They crawl onto the hummingbird to
hitch a lift to another plant.

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At the next stop, some passengers get off
and others get on.

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Not every animal works
in such harmony with the puyas.

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The growing flower spikes are
an irresistible honeypot

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for spectacled bears.

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They can destroy a
lifetime's work in seconds.

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For bear cubs, learning how to tackle
puyas brings a sweet reward.

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The spikes are rich in sugar

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to make nectar
for the hundreds of flowers.

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They're packed with energy
but how do you get at it?

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A little parental guidance
is called for.

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Spectacled bears are versatile animals

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but each new generation has to
learn the tricks of the trade.

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The mountains are an
unpredictable place to call home.

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Massive volcanoes rise
above the cloud forest.

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At any moment
they can burst into violent life.

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As you travel south down
the chain of the Andes

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you pass a line of brooding giants.

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Among them are the highest
active volcanoes in the world

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rising to more
than six thousand metres.

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They're so high that even
in the tropics

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their summits are crowned
with ice and snow.

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In the heart of the Andes

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volcanic activity has built more
than mountain peaks.

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It's thrust a high desert plateau

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three miles up into the sky
the Altiplano.

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Sulphurous steam from the world's highest
geyser field rises into cold

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thin air... a vision of earth
before life began.

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Much of the water here evaporates
in huge caustic lakes.

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This must be one of the most
extreme environments on earth.

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How could anything
possibly live here?

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Incredibly

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the Altiplano salt lakes
actually attract animals.

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Flamingos come here to breed.

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Their season starts
with a massed courtship dance.

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Three kinds of flamingo nest
on these caustic lakes.

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These ones are Andean flamingos.

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These lakes are prime flamingo habitat.

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With no outlet
dissolved salts washed down

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from the surrounding mountains are
concentrated by evaporation

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ideal conditions for the flamingos
favourite food - brine shrimps.

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They thrive in water ten times
as salty as the sea.

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The birds catch them by filtering water
through bony combs in their beaks.

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The three kinds of flamingo
have different sized 'filters'

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so they can live together by exploiting
different parts of this briny soup.

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Only a handful of other waterbirds
can live here.

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Andean avocets subsist on fly larvae.

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The key to success up here
is being a specialist.

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Brine flies live in a world
that's wafer-thin

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sandwiched between the salt
and the piercing wind.

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But their swarms are large
enough to support a lizard.

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Brine flies are its staple diet.

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Being cold blooded

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it hunts only when the temperature
has risen enough for it to move.

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For a lizard living on the edge
of what's possible

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even a patch of fly-blown salt pan
is worth fighting for.

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Even the steaming outflow
from a geyser attracts life.

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This frog also survives on flies

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but this really is living on the edge.

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A few hops one way
and it would be boiled alive

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a few the other
and it would freeze to death.

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This desert on the roof of the world
even has mammals

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Vicuna
South American relatives of the camel.

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But what can they eat up here?

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There's more to the Altiplano
than caustic lakes

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and not all the springs
are hot and salty.

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Fed by meltwater from the snow-clad peaks
some run cold and fresh.

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They water small patches of marsh
called bofedales.

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In the drier parts of the Altiplano

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these green oases are the key
to the vicunas' survival.

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They provide grazing
and fresh water to drink.

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All sorts of animals depend on them.

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Like viscachas
rabbit-sized rodents.

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Early in the morning
the marsh is frozen hard

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so the viscachas bask in the sun
until the ground warms up

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along with the leaf-eared mice
that share their jumble of boulders.

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Only when the grass has thawed
can they start to graze.

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In the drier parts of the Altiplano
little grows away from the bofedales.

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The few flowers give a sip of nectar
for the Andean Hillstar.

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Up here perching is vital to
save energy in the thin air.

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There may be no woods here

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but there is a woodpecker
the Andean flicker.

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It nests underground
and hunts for insect grubs in the marsh.

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At this extreme altitude

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the main problems any animal has to
face are cold and lack of oxygen.

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Viscachas overcome the cold
by having incredibly thick fur

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but they have to keep it in good shape
if it's to save them from freezing.

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To make better use of the thin air

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some animals have a high concentration
of red blood cells

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and specialised lungs.

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It also helps
if you don't exert yourself.

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Viscachas hardly ever move more

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than a stone's throw
from their protective rocks.

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Nothing moves fast
without a good reason

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but up here, even a small patch
of grass is worth fighting for.

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Deciding whether to use
hard-won energy reserves

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can be a matter of life and death.

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The arrival of a red fox
means it's decision time.

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Up here the air is so starved of oxygen
that a sustained chase is impossible.

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The fox has to try and take its prey
by surprise

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Not easy in this open country.

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The viscachas are rarely more
than a short dash from safety.

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Viscachas have thin muscle walls
to their lungs

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so they can breathe more freely
at high altitude.

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But a rapid escape is exhausting
even for them.

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The panic's over for now.

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It's time for everyone to
catch their breath.

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On the Altiplano
the air is in such short supply

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that neither hunter nor hunted
can afford to waste it.

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00:21:20,812 --> 00:21:25,112
It's at night that the effects of
the high altitude bite hardest.

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00:21:29,388 --> 00:21:30,548
When the sun goes down

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00:21:30,689 --> 00:21:33,249
the air's too thin to retain its heat

191
00:21:33,592 --> 00:21:35,617
and the temperature plummets.

192
00:21:44,870 --> 00:21:48,670
For the Andean Hillstar
every night is like a winter.

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00:21:49,341 --> 00:21:50,706
Even at lower altitudes

194
00:21:50,842 --> 00:21:54,835
hummingbirds save energy at night
by slowing down their metabolism

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00:21:54,980 --> 00:21:57,642
almost as if they were hibernating.

196
00:22:00,552 --> 00:22:06,081
Up here, that ability can make the
difference between life and death.

197
00:22:07,726 --> 00:22:12,527
Just three hours after sunset
it's already twenty below.

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00:22:14,533 --> 00:22:17,468
Even running water freezes hard.

199
00:22:31,149 --> 00:22:34,778
This is the moment of truth
for the Hillstar.

200
00:22:35,153 --> 00:22:38,122
Now all it can do is wait.

201
00:23:07,219 --> 00:23:11,280
With the rising sun
the Hillstar comes alive again.

202
00:23:11,690 --> 00:23:14,523
It picked its roosting place
so the very first rays

203
00:23:14,659 --> 00:23:17,423
reach in to warm its chilled body.

204
00:23:20,031 --> 00:23:22,431
This time, it's won through

205
00:23:22,634 --> 00:23:26,866
Every night is a battle to
survive a twelve hour winter.

206
00:23:28,907 --> 00:23:32,172
But the Altiplano also
has a true winter.

207
00:23:32,778 --> 00:23:34,302
For a few weeks each year

208
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its savage climate
becomes even more severe.

209
00:23:39,651 --> 00:23:42,711
For those who can
this is time to leave.

210
00:23:44,523 --> 00:23:47,981
They must search for food in lakes
lower down the mountains.

211
00:24:08,480 --> 00:24:10,004
When the flamingos have gone

212
00:24:10,148 --> 00:24:13,083
the high Altiplano is left
to the elements

213
00:24:13,218 --> 00:24:16,710
and those animals
that have no choice but to sit it out.

214
00:24:23,628 --> 00:24:28,429
The cold can be so severe
that even the salt lakes freeze over.

215
00:24:35,173 --> 00:24:39,234
Any birds that breed late in the season
can be trapped here.

216
00:24:39,845 --> 00:24:41,278
Their young can't yet fly

217
00:24:41,480 --> 00:24:45,610
and their food is now out of reach
locked beneath the ice.

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00:24:55,126 --> 00:24:59,085
Many of these stragglers will die
frozen into the ice.

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00:24:59,931 --> 00:25:02,559
Their fate is already sealed.

220
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But some places never freeze.

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The Andes' inner fires keep the geysers
and hot springs free of ice.

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00:25:25,690 --> 00:25:28,488
Here at least, winter will never come.

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In this tiny island of warmth
in the most marginal

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and extreme of worlds, life hangs on.

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The Altiplano may be extreme

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00:25:52,984 --> 00:25:56,750
but there's somewhere
even more severe.

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As you travel south down
the chain of the Andes

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winter becomes even harder.

229
00:26:04,563 --> 00:26:08,158
The mountains here may not be
as high as the giants further north

230
00:26:08,300 --> 00:26:10,928
but they're much closer
to the Antarctic.

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00:26:13,071 --> 00:26:15,539
The snowline creeps lower
and lower

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00:26:15,674 --> 00:26:19,405
and in the deep south
the ice never melts.

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00:26:19,711 --> 00:26:22,271
This is Patagonia.

234
00:26:31,856 --> 00:26:36,293
Three huge ice-sheets dominate
the Patagonian Andes.

235
00:26:36,628 --> 00:26:39,290
Covering over seven thousand
square miles

236
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they're the largest expanse of
ice outside the poles

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so vast that they generate
their own weather.

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00:27:10,095 --> 00:27:13,531
Towers of rock rise
from the edge of the ice

239
00:27:13,665 --> 00:27:18,659
the remnants of ancient volcanoes
stripped bare by the glaciers.

240
00:27:38,757 --> 00:27:42,659
Only the condor soars among
these icy peaks.

241
00:27:48,967 --> 00:27:52,130
This is one of the windiest places
on earth.

242
00:27:53,772 --> 00:27:56,832
Chilled air spills
from the edge of the ice-sheet.

243
00:27:56,975 --> 00:27:59,671
Funnelled down the glaciers
and between the peaks

244
00:27:59,811 --> 00:28:03,770
these freezing blasts can reach
a hundred miles an hour.

245
00:28:06,718 --> 00:28:10,518
Almost nothing lives
on the ice-sheet itself.

246
00:28:10,655 --> 00:28:15,524
Surviving even on its edge requires
unimaginable stamina.

247
00:28:22,634 --> 00:28:26,434
The guanaco
a southern cousin of the vicuna.

248
00:28:26,738 --> 00:28:29,434
It's larger
and has a thick woolly coat

249
00:28:29,574 --> 00:28:33,271
and it needs it
to survive the Patagonian winter.

250
00:28:45,924 --> 00:28:49,655
Snow is not the only peril
the guanacos face.

251
00:28:53,565 --> 00:28:56,932
The puma, the lion of the Andes.

252
00:28:58,369 --> 00:29:02,169
This most adaptable of big cats lives
throughout the mountain chain

253
00:29:02,307 --> 00:29:04,172
from the cloud forest to
the high desert

254
00:29:04,309 --> 00:29:10,441
and the snows of Patagonia
but it's secretive and hardly ever seen.

255
00:29:15,086 --> 00:29:18,817
For all the hunters here
winter is a lean season.

256
00:29:18,957 --> 00:29:21,949
They're poorly camouflaged
against the snow.

257
00:29:22,293 --> 00:29:27,196
The grey fox follows the puma to
scavenge any scraps from its kills.

258
00:29:27,699 --> 00:29:30,725
She has hidden stores of food
during the summer.

259
00:29:30,869 --> 00:29:34,305
If she can sniff them out
she'll survive the winter.

260
00:29:49,120 --> 00:29:52,317
The really hard times
last four months.

261
00:29:52,457 --> 00:29:57,417
But slowly the days get longer
and the land comes back to life.

262
00:30:06,971 --> 00:30:09,906
The snowline creeps back up
the mountains.

263
00:30:10,041 --> 00:30:13,033
This is what the condors
have been waiting for.

264
00:30:17,081 --> 00:30:21,211
As the snow retreats
the casualties of winter are revealed

265
00:30:21,352 --> 00:30:27,154
animals killed by cold or starvation
and the remnants of puma kills.

266
00:30:29,627 --> 00:30:32,255
Condors are the vultures of the Andes.

267
00:30:32,397 --> 00:30:33,887
They have superb eyesight.

268
00:30:34,032 --> 00:30:36,227
They can spot food from miles away

269
00:30:36,367 --> 00:30:38,665
and can locate even more
distant carcasses

270
00:30:38,803 --> 00:30:41,704
by watching
for other condors gathering.

271
00:30:52,350 --> 00:30:55,251
The grey fox is a scavenger too.

272
00:30:55,887 --> 00:30:58,355
The winter's survivors
are lean and hungry

273
00:30:58,489 --> 00:31:02,084
and there's stiff competition
for any chance of a meal.

274
00:31:11,135 --> 00:31:14,502
There's a well defined pecking order
at carcasses.

275
00:31:18,209 --> 00:31:20,336
One fox may defer to another

276
00:31:20,478 --> 00:31:22,878
but neither of them can argue
with a condor.

277
00:31:33,124 --> 00:31:36,855
With a three metre wingspan
and weighing up to fifteen kilos

278
00:31:36,995 --> 00:31:39,759
it's the world's largest
flying bird.

279
00:31:45,036 --> 00:31:47,368
The fox simply can't compete.

280
00:31:50,675 --> 00:31:53,940
At this feast the condor is king.

281
00:31:59,050 --> 00:32:01,610
Caracaras have to wait
their turn too

282
00:32:01,753 --> 00:32:05,314
or make do with scraps that fall
from the condors' table.

283
00:32:16,734 --> 00:32:19,703
Spring brings a flood of migrants
to take advantage

284
00:32:19,837 --> 00:32:24,331
of the brief Patagonian summer
like buff-necked ibis.

285
00:32:26,177 --> 00:32:29,044
They waste no time
in starting to breed.

286
00:32:44,195 --> 00:32:46,561
Great grebes over-winter on the coast

287
00:32:46,698 --> 00:32:48,461
but as soon as the lakes
are free of ice

288
00:32:48,566 --> 00:32:51,535
they move inland and start fighting
for territory.

289
00:33:17,628 --> 00:33:20,961
Only the winners will have a good chance
of raising a family

290
00:33:21,099 --> 00:33:23,897
The losers are forced onto lakes higher
in the mountains

291
00:33:24,035 --> 00:33:26,503
where the summer is that much shorter.

292
00:33:32,744 --> 00:33:36,874
Territory is also the key to breeding
for male guanacos.

293
00:33:37,482 --> 00:33:40,178
They gather a group of females
on their patch of ground

294
00:33:40,318 --> 00:33:43,583
and guard them closely
against rival males.

295
00:33:45,056 --> 00:33:47,456
He must always be on watch.

296
00:33:47,625 --> 00:33:51,959
Younger males will seize any opportunity
to raid the harem.

297
00:33:57,201 --> 00:34:01,228
Soon the reedbeds are alive
with nesting birds.

298
00:34:06,811 --> 00:34:10,474
And where there are nests
there are nest thieves.

299
00:34:15,319 --> 00:34:19,312
As soon as eggs are laid
the fox is quick to take advantage.

300
00:34:30,334 --> 00:34:33,098
She's found the nest of
an upland goose.

301
00:34:33,337 --> 00:34:36,101
Now the birds will have to
start all over again.

302
00:34:40,011 --> 00:34:43,845
There's little a bird can do to drive
a fox away from its nest.

303
00:34:46,551 --> 00:34:50,112
But a male guanaco packs
more of a punch.

304
00:34:52,256 --> 00:34:56,090
Soon there will be baby
guanacos to defend

305
00:34:56,527 --> 00:34:59,257
and he's not taking any chances.

306
00:35:15,980 --> 00:35:19,438
Male guanacos are exceedingly territorial
at this time of year

307
00:35:19,584 --> 00:35:22,519
and they won't tolerate intruders
of any kind.

308
00:35:28,059 --> 00:35:30,425
The fox already has a family to feed.

309
00:35:30,528 --> 00:35:34,464
Her cubs will be safer away
from the aggressive guanacos' territory

310
00:35:34,599 --> 00:35:36,863
so she moves them to another den.

311
00:35:50,314 --> 00:35:53,841
There can be as many
as five cubs in a litter.

312
00:35:54,051 --> 00:35:57,179
Their mother has to carry each
individually to the new den

313
00:35:57,321 --> 00:36:00,154
so moving house takes a lot of energy.

314
00:36:00,625 --> 00:36:04,823
Even so, foxes often move
their cubs several times.

315
00:36:05,096 --> 00:36:06,927
The longer a den is occupied

316
00:36:07,064 --> 00:36:10,158
the greater the chance a puma
will find it.

317
00:36:13,571 --> 00:36:16,131
The cubs are still dependent
on their mother's milk

318
00:36:16,274 --> 00:36:19,675
but soon she'll be weaning them
onto solid food.

319
00:36:19,944 --> 00:36:24,142
By the time winter returns
they'll have to look after themselves.

320
00:36:36,494 --> 00:36:39,292
Few of these cubs will live
as long as a year.

321
00:36:39,463 --> 00:36:42,023
If they're to survive
they have a lot to learn

322
00:36:42,166 --> 00:36:44,532
and only a brief summer to learn it.

323
00:36:59,350 --> 00:37:01,750
High summer in Patagonia.

324
00:37:18,436 --> 00:37:20,631
At the edge of
the great ice-sheet

325
00:37:20,771 --> 00:37:23,638
the mountains are almost
clear of snow.

326
00:37:29,280 --> 00:37:32,545
This far south
midsummer days are long

327
00:37:32,783 --> 00:37:35,980
and occasionally it can even be warm.

328
00:37:39,790 --> 00:37:43,021
Patagonia seems almost benign.

329
00:37:44,295 --> 00:37:49,426
The puma hunts mostly at night
but summer nights are short.

330
00:37:50,468 --> 00:37:52,527
There may be more food
at this time of year

331
00:37:52,670 --> 00:37:55,571
but there's less time
for the puma to catch it.

332
00:38:01,512 --> 00:38:05,812
At dusk, a deadly game of cat
and mouse begins.

333
00:38:17,428 --> 00:38:20,124
The guanacos move to the ridge tops.

334
00:38:20,331 --> 00:38:24,427
From there they have a better chance
of spotting a prowling puma.

335
00:38:27,738 --> 00:38:29,205
But under cover of darkness

336
00:38:29,340 --> 00:38:32,434
the odds are stacked
in the big cat's favour.

337
00:38:56,100 --> 00:38:59,433
This time the puma killed
a full grown guanaco

338
00:38:59,570 --> 00:39:02,130
but the most vulnerable are the young.

339
00:39:02,273 --> 00:39:06,403
The cat won't have long to wait
for the new season's baby guanacos.

340
00:39:20,424 --> 00:39:23,951
All the births are concentrated
over just a few days.

341
00:39:24,095 --> 00:39:26,427
That way the puma is spoilt
for choice

342
00:39:26,564 --> 00:39:28,896
and it can't take all the young.

343
00:39:35,106 --> 00:39:36,835
The sooner a new-born
infant can stand

344
00:39:36,974 --> 00:39:41,035
and run, the better its chances
of surviving the summer.

345
00:39:56,127 --> 00:40:00,120
Within days of giving birth
the female guanacos come on heat.

346
00:40:02,600 --> 00:40:05,569
For the males, this will be the payoff
for all the hard work

347
00:40:05,703 --> 00:40:08,001
they've put into defending their harem.

348
00:40:09,006 --> 00:40:11,566
But they can't afford to
relax their guard.

349
00:40:12,977 --> 00:40:16,708
This is when other males are
most tempted to intrude.

350
00:40:19,417 --> 00:40:21,942
First, there's a stand off.

351
00:40:28,392 --> 00:40:30,519
Fighting's dangerous so males

352
00:40:30,661 --> 00:40:34,222
try to intimidate their opponents
by posturing.

353
00:40:39,837 --> 00:40:44,103
But this time
threat has to be backed by physical force.

354
00:40:56,787 --> 00:40:59,017
Guanacos are heavy, powerful animals

355
00:40:59,156 --> 00:41:01,647
and they can inflict a vicious bite.

356
00:41:17,374 --> 00:41:21,435
This 'neck wrestling' is a way
of avoiding being bitten.

357
00:41:59,416 --> 00:42:02,681
The battle over
the winner takes his reward.

358
00:42:05,656 --> 00:42:07,419
So long as he can fend off intruders

359
00:42:07,525 --> 00:42:11,325
the resident male will mate
with all the females in his group

360
00:42:11,462 --> 00:42:14,226
and sire a whole new generation.

361
00:42:23,774 --> 00:42:26,334
This may be midsummer
but at any time

362
00:42:26,477 --> 00:42:29,571
the mountain can spring
a cruel surprise.

363
00:42:37,955 --> 00:42:39,513
On a sunny summer's day

364
00:42:39,657 --> 00:42:42,717
ferocious storms can strike
out of the blue.

365
00:42:56,607 --> 00:42:58,507
From behind its fringing peaks

366
00:42:58,642 --> 00:43:02,874
the ice-cap hurls a frozen blast
down the mountains.

367
00:43:14,358 --> 00:43:17,725
These sudden winds can reach
a hundred miles an hour.

368
00:43:57,368 --> 00:43:58,699
For everything that lives here

369
00:43:58,836 --> 00:44:02,397
these sudden storms are part
of the Patagonian summer.

370
00:44:02,673 --> 00:44:04,971
They can strike almost daily.

371
00:44:09,880 --> 00:44:13,543
Even in the strongest winds
the grebes keep fishing.

372
00:44:16,720 --> 00:44:19,416
All kinds of grebe carry their
young on their back

373
00:44:19,556 --> 00:44:22,616
but here in Patagonia
it's a life saver.

374
00:44:26,130 --> 00:44:27,256
From their earliest days

375
00:44:27,464 --> 00:44:30,729
the chicks feel the brutal
force of the Andes.

376
00:44:31,735 --> 00:44:33,566
But these birds
are great survivors

377
00:44:33,704 --> 00:44:35,729
and if they can make it
through the storms

378
00:44:35,873 --> 00:44:37,773
this is an ideal home.

379
00:44:50,487 --> 00:44:53,547
Sometimes grebes feed feathers
to their chicks.

380
00:44:53,691 --> 00:44:55,989
This may help bind
the fish bones together

381
00:44:56,126 --> 00:44:59,562
so they can be regurgitated safely
as a pellet.

382
00:45:08,105 --> 00:45:10,403
Young of all kinds have to grow fast

383
00:45:10,474 --> 00:45:12,772
if they're to survive
the coming winter.

384
00:45:15,946 --> 00:45:18,005
The young guanacos build up
their stamina

385
00:45:18,148 --> 00:45:20,742
by playing in the last of
the summer sun.

386
00:45:32,096 --> 00:45:34,428
The mother fox has
only a few more weeks

387
00:45:34,498 --> 00:45:37,661
to teach her cubs how to fend
for themselves.

388
00:45:38,335 --> 00:45:43,238
Carrion from a puma kill gives them
their first taste of red meat.

389
00:45:43,373 --> 00:45:45,102
But meat is a luxury.

390
00:45:45,242 --> 00:45:51,442
To survive they will have to eat insects
fruit, leaves, even grass.

391
00:45:56,153 --> 00:45:57,484
They may be playing now

392
00:45:57,621 --> 00:46:01,057
but in a few weeks they'll
be hunting for real

393
00:46:01,191 --> 00:46:02,419
on their own.

394
00:46:04,928 --> 00:46:08,625
Only the most resourceful can
live through an Andean winter.

395
00:46:12,436 --> 00:46:14,597
All along the chain of the Andes

396
00:46:14,738 --> 00:46:20,040
survival depends on adapting to some of
the harshest conditions on the planet

397
00:46:20,177 --> 00:46:24,045
thin air, bitter cold, relentless wind.

398
00:46:35,592 --> 00:46:37,287
But for those that can live here

399
00:46:37,461 --> 00:46:40,430
the mountains provide all their needs.

400
00:46:55,212 --> 00:46:59,114
Our journey of over five thousand
miles ends here

401
00:46:59,249 --> 00:47:01,012
almost in the Antarctic

402
00:47:01,151 --> 00:47:05,383
where the glaciers of Patagonia plunge
towards the Southern Ocean.

403
00:47:45,262 --> 00:47:48,129
The mighty force of the mountains
can give life

404
00:47:48,265 --> 00:47:49,425
but at any moment

405
00:47:49,533 --> 00:47:51,228
it can take it away.

406
00:47:52,102 --> 00:47:53,933
Living in the Andes

407
00:47:54,071 --> 00:47:57,438
is one of the greatest
challenges in the natural world.