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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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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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It's at night that the effects of
the high altitude bite hardest.

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When the sun goes down

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00:21:29,189 --> 00:21:31,749
the air's too thin to retain its heat

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and the temperature plummets.

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00:21:43,370 --> 00:21:47,170
For the Andean Hillstar
every night is like a winter.

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00:21:47,841 --> 00:21:49,206
Even at lower altitudes

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00:21:49,342 --> 00:21:53,335
hummingbirds save energy at night
by slowing down their metabolism

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00:21:53,480 --> 00:21:56,142
almost as if they were hibernating.

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00:21:59,052 --> 00:22:04,581
Up here, that ability can make the
difference between life and death.

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Just three hours after sunset
it's already twenty below.

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00:22:13,033 --> 00:22:15,968
Even running water freezes hard.

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00:22:29,649 --> 00:22:33,278
This is the moment of truth
for the Hillstar.

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00:22:33,653 --> 00:22:36,622
Now all it can do is wait.

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With the rising sun
the Hillstar comes alive again.

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It picked its roosting place
so the very first rays

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reach in to warm its chilled body.

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This time, it's won through

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00:23:21,134 --> 00:23:25,366
Every night is a battle to
survive a twelve hour winter.

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00:23:27,407 --> 00:23:30,672
But the Altiplano also
has a true winter.

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00:23:31,278 --> 00:23:32,802
For a few weeks each year

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00:23:32,979 --> 00:23:36,540
its savage climate
becomes even more severe.

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00:23:38,151 --> 00:23:41,211
For those who can
this is time to leave.

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00:23:43,023 --> 00:23:46,481
They must search for food in lakes
lower down the mountains.

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00:24:06,980 --> 00:24:08,504
When the flamingos have gone

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00:24:08,648 --> 00:24:11,583
the high Altiplano is left
to the elements

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00:24:11,718 --> 00:24:15,210
and those animals
that have no choice but to sit it out.

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00:24:22,128 --> 00:24:26,929
The cold can be so severe
that even the salt lakes freeze over.

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00:24:33,673 --> 00:24:37,734
Any birds that breed late in the season
can be trapped here.

216
00:24:38,345 --> 00:24:39,778
Their young can't yet fly

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00:24:39,980 --> 00:24:44,110
and their food is now out of reach
locked beneath the ice.

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00:24:53,626 --> 00:24:57,585
Many of these stragglers will die
frozen into the ice.

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Their fate is already sealed.

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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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00:25:24,190 --> 00:25:26,988
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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00:25:51,484 --> 00:25:55,250
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.

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00:26:03,063 --> 00:26:06,658
The mountains here may not be
as high as the giants further north

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00:26:06,800 --> 00:26:09,428
but they're much closer
to the Antarctic.

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00:26:11,571 --> 00:26:14,039
The snowline creeps lower
and lower

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00:26:14,174 --> 00:26:17,905
and in the deep south
the ice never melts.

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00:26:18,211 --> 00:26:20,771
This is Patagonia.

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00:26:30,356 --> 00:26:34,793
Three huge ice-sheets dominate
the Patagonian Andes.

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00:26:35,128 --> 00:26:37,790
Covering over seven thousand
square miles

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00:26:37,964 --> 00:26:41,263
they're the largest expanse of
ice outside the poles

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00:26:41,401 --> 00:26:44,928
so vast that they generate
their own weather.

238
00:27:08,595 --> 00:27:12,031
Towers of rock rise
from the edge of the ice

239
00:27:12,165 --> 00:27:17,159
the remnants of ancient volcanoes
stripped bare by the glaciers.

240
00:27:37,257 --> 00:27:41,159
Only the condor soars among
these icy peaks.

241
00:27:47,467 --> 00:27:50,630
This is one of the windiest places
on earth.

242
00:27:52,272 --> 00:27:55,332
Chilled air spills
from the edge of the ice-sheet.

243
00:27:55,475 --> 00:27:58,171
Funnelled down the glaciers
and between the peaks

244
00:27:58,311 --> 00:28:02,270
these freezing blasts can reach
a hundred miles an hour.

245
00:28:05,218 --> 00:28:09,018
Almost nothing lives
on the ice-sheet itself.

246
00:28:09,155 --> 00:28:14,024
Surviving even on its edge requires
unimaginable stamina.

247
00:28:21,134 --> 00:28:24,934
The guanaco
a southern cousin of the vicuna.

248
00:28:25,238 --> 00:28:27,934
It's larger
and has a thick woolly coat

249
00:28:28,074 --> 00:28:31,771
and it needs it
to survive the Patagonian winter.

250
00:28:44,424 --> 00:28:48,155
Snow is not the only peril
the guanacos face.

251
00:28:52,065 --> 00:28:55,432
The puma, the lion of the Andes.

252
00:28:56,869 --> 00:29:00,669
This most adaptable of big cats lives
throughout the mountain chain

253
00:29:00,807 --> 00:29:02,672
from the cloud forest to
the high desert

254
00:29:02,809 --> 00:29:08,941
and the snows of Patagonia
but it's secretive and hardly ever seen.

255
00:29:13,586 --> 00:29:17,317
For all the hunters here
winter is a lean season.

256
00:29:17,457 --> 00:29:20,449
They're poorly camouflaged
against the snow.

257
00:29:20,793 --> 00:29:25,696
The grey fox follows the puma to
scavenge any scraps from its kills.

258
00:29:26,199 --> 00:29:29,225
She has hidden stores of food
during the summer.

259
00:29:29,369 --> 00:29:32,805
If she can sniff them out
she'll survive the winter.

260
00:29:47,620 --> 00:29:50,817
The really hard times
last four months.

261
00:29:50,957 --> 00:29:55,917
But slowly the days get longer
and the land comes back to life.

262
00:30:05,471 --> 00:30:08,406
The snowline creeps back up
the mountains.

263
00:30:08,541 --> 00:30:11,533
This is what the condors
have been waiting for.

264
00:30:15,581 --> 00:30:19,711
As the snow retreats
the casualties of winter are revealed

265
00:30:19,852 --> 00:30:25,654
animals killed by cold or starvation
and the remnants of puma kills.

266
00:30:28,127 --> 00:30:30,755
Condors are the vultures of the Andes.

267
00:30:30,897 --> 00:30:32,387
They have superb eyesight.

268
00:30:32,532 --> 00:30:34,727
They can spot food from miles away

269
00:30:34,867 --> 00:30:37,165
and can locate even more
distant carcasses

270
00:30:37,303 --> 00:30:40,204
by watching
for other condors gathering.

271
00:30:50,850 --> 00:30:53,751
The grey fox is a scavenger too.

272
00:30:54,387 --> 00:30:56,855
The winter's survivors
are lean and hungry

273
00:30:56,989 --> 00:31:00,584
and there's stiff competition
for any chance of a meal.

274
00:31:09,635 --> 00:31:13,002
There's a well defined pecking order
at carcasses.

275
00:31:16,709 --> 00:31:18,836
One fox may defer to another

276
00:31:18,978 --> 00:31:21,378
but neither of them can argue
with a condor.

277
00:31:31,624 --> 00:31:35,355
With a three metre wingspan
and weighing up to fifteen kilos

278
00:31:35,495 --> 00:31:38,259
it's the world's largest
flying bird.

279
00:31:43,536 --> 00:31:45,868
The fox simply can't compete.

280
00:31:49,175 --> 00:31:52,440
At this feast the condor is king.

281
00:31:57,550 --> 00:32:00,110
Caracaras have to wait
their turn too

282
00:32:00,253 --> 00:32:03,814
or make do with scraps that fall
from the condors' table.

283
00:32:15,234 --> 00:32:18,203
Spring brings a flood of migrants
to take advantage

284
00:32:18,337 --> 00:32:22,831
of the brief Patagonian summer
like buff-necked ibis.

285
00:32:24,677 --> 00:32:27,544
They waste no time
in starting to breed.

286
00:32:42,695 --> 00:32:45,061
Great grebes over-winter on the coast

287
00:32:45,198 --> 00:32:46,961
but as soon as the lakes
are free of ice

288
00:32:47,066 --> 00:32:50,035
they move inland and start fighting
for territory.

289
00:33:16,128 --> 00:33:19,461
Only the winners will have a good chance
of raising a family

290
00:33:19,599 --> 00:33:22,397
The losers are forced onto lakes higher
in the mountains

291
00:33:22,535 --> 00:33:25,003
where the summer is that much shorter.

292
00:33:31,244 --> 00:33:35,374
Territory is also the key to breeding
for male guanacos.

293
00:33:35,982 --> 00:33:38,678
They gather a group of females
on their patch of ground

294
00:33:38,818 --> 00:33:42,083
and guard them closely
against rival males.

295
00:33:43,556 --> 00:33:45,956
He must always be on watch.

296
00:33:46,125 --> 00:33:50,459
Younger males will seize any opportunity
to raid the harem.

297
00:33:55,701 --> 00:33:59,728
Soon the reedbeds are alive
with nesting birds.

298
00:34:05,311 --> 00:34:08,974
And where there are nests
there are nest thieves.

299
00:34:13,819 --> 00:34:17,812
As soon as eggs are laid
the fox is quick to take advantage.

300
00:34:28,834 --> 00:34:31,598
She's found the nest of
an upland goose.

301
00:34:31,837 --> 00:34:34,601
Now the birds will have to
start all over again.

302
00:34:38,511 --> 00:34:42,345
There's little a bird can do to drive
a fox away from its nest.

303
00:34:45,051 --> 00:34:48,612
But a male guanaco packs
more of a punch.

304
00:34:50,756 --> 00:34:54,590
Soon there will be baby
guanacos to defend

305
00:34:55,027 --> 00:34:57,757
and he's not taking any chances.

306
00:35:14,480 --> 00:35:17,938
Male guanacos are exceedingly territorial
at this time of year

307
00:35:18,084 --> 00:35:21,019
and they won't tolerate intruders
of any kind.

308
00:35:26,559 --> 00:35:28,925
The fox already has a family to feed.

309
00:35:29,028 --> 00:35:32,964
Her cubs will be safer away
from the aggressive guanacos' territory

310
00:35:33,099 --> 00:35:35,363
so she moves them to another den.

311
00:35:48,814 --> 00:35:52,341
There can be as many
as five cubs in a litter.

312
00:35:52,551 --> 00:35:55,679
Their mother has to carry each
individually to the new den

313
00:35:55,821 --> 00:35:58,654
so moving house takes a lot of energy.

314
00:35:59,125 --> 00:36:03,323
Even so, foxes often move
their cubs several times.

315
00:36:03,596 --> 00:36:05,427
The longer a den is occupied

316
00:36:05,564 --> 00:36:08,658
the greater the chance a puma
will find it.

317
00:36:12,071 --> 00:36:14,631
The cubs are still dependent
on their mother's milk

318
00:36:14,774 --> 00:36:18,175
but soon she'll be weaning them
onto solid food.

319
00:36:18,444 --> 00:36:22,642
By the time winter returns
they'll have to look after themselves.

320
00:36:34,994 --> 00:36:37,792
Few of these cubs will live
as long as a year.

321
00:36:37,963 --> 00:36:40,523
If they're to survive
they have a lot to learn

322
00:36:40,666 --> 00:36:43,032
and only a brief summer to learn it.

323
00:36:57,850 --> 00:37:00,250
High summer in Patagonia.

324
00:37:16,936 --> 00:37:19,131
At the edge of
the great ice-sheet

325
00:37:19,271 --> 00:37:22,138
the mountains are almost
clear of snow.

326
00:37:27,780 --> 00:37:31,045
This far south
midsummer days are long

327
00:37:31,283 --> 00:37:34,480
and occasionally it can even be warm.

328
00:37:38,290 --> 00:37:41,521
Patagonia seems almost benign.

329
00:37:42,795 --> 00:37:47,926
The puma hunts mostly at night
but summer nights are short.

330
00:37:48,968 --> 00:37:51,027
There may be more food
at this time of year

331
00:37:51,170 --> 00:37:54,071
but there's less time
for the puma to catch it.

332
00:38:00,012 --> 00:38:04,312
At dusk, a deadly game of cat
and mouse begins.

333
00:38:15,928 --> 00:38:18,624
The guanacos move to the ridge tops.

334
00:38:18,831 --> 00:38:22,927
From there they have a better chance
of spotting a prowling puma.

335
00:38:26,238 --> 00:38:27,705
But under cover of darkness

336
00:38:27,840 --> 00:38:30,934
the odds are stacked
in the big cat's favour.

337
00:38:54,600 --> 00:38:57,933
This time the puma killed
a full grown guanaco

338
00:38:58,070 --> 00:39:00,630
but the most vulnerable are the young.

339
00:39:00,773 --> 00:39:04,903
The cat won't have long to wait
for the new season's baby guanacos.

340
00:39:18,924 --> 00:39:22,451
All the births are concentrated
over just a few days.

341
00:39:22,595 --> 00:39:24,927
That way the puma is spoilt
for choice

342
00:39:25,064 --> 00:39:27,396
and it can't take all the young.

343
00:39:33,606 --> 00:39:35,335
The sooner a new-born
infant can stand

344
00:39:35,474 --> 00:39:39,535
and run, the better its chances
of surviving the summer.

345
00:39:54,627 --> 00:39:58,620
Within days of giving birth
the female guanacos come on heat.

346
00:40:01,100 --> 00:40:04,069
For the males, this will be the payoff
for all the hard work

347
00:40:04,203 --> 00:40:06,501
they've put into defending their harem.

348
00:40:07,506 --> 00:40:10,066
But they can't afford to
relax their guard.

349
00:40:11,477 --> 00:40:15,208
This is when other males are
most tempted to intrude.

350
00:40:17,917 --> 00:40:20,442
First, there's a stand off.

351
00:40:26,892 --> 00:40:29,019
Fighting's dangerous so males

352
00:40:29,161 --> 00:40:32,722
try to intimidate their opponents
by posturing.

353
00:40:38,337 --> 00:40:42,603
But this time
threat has to be backed by physical force.

354
00:40:55,287 --> 00:40:57,517
Guanacos are heavy, powerful animals

355
00:40:57,656 --> 00:41:00,147
and they can inflict a vicious bite.

356
00:41:15,874 --> 00:41:19,935
This 'neck wrestling' is a way
of avoiding being bitten.

357
00:41:57,916 --> 00:42:01,181
The battle over
the winner takes his reward.

358
00:42:04,156 --> 00:42:05,919
So long as he can fend off intruders

359
00:42:06,025 --> 00:42:09,825
the resident male will mate
with all the females in his group

360
00:42:09,962 --> 00:42:12,726
and sire a whole new generation.

361
00:42:22,274 --> 00:42:24,834
This may be midsummer
but at any time

362
00:42:24,977 --> 00:42:28,071
the mountain can spring
a cruel surprise.

363
00:42:36,455 --> 00:42:38,013
On a sunny summer's day

364
00:42:38,157 --> 00:42:41,217
ferocious storms can strike
out of the blue.

365
00:42:55,107 --> 00:42:57,007
From behind its fringing peaks

366
00:42:57,142 --> 00:43:01,374
the ice-cap hurls a frozen blast
down the mountains.

367
00:43:12,858 --> 00:43:16,225
These sudden winds can reach
a hundred miles an hour.

368
00:43:55,868 --> 00:43:57,199
For everything that lives here

369
00:43:57,336 --> 00:44:00,897
these sudden storms are part
of the Patagonian summer.

370
00:44:01,173 --> 00:44:03,471
They can strike almost daily.

371
00:44:08,380 --> 00:44:12,043
Even in the strongest winds
the grebes keep fishing.

372
00:44:15,220 --> 00:44:17,916
All kinds of grebe carry their
young on their back

373
00:44:18,056 --> 00:44:21,116
but here in Patagonia
it's a life saver.

374
00:44:24,630 --> 00:44:25,756
From their earliest days

375
00:44:25,964 --> 00:44:29,229
the chicks feel the brutal
force of the Andes.

376
00:44:30,235 --> 00:44:32,066
But these birds
are great survivors

377
00:44:32,204 --> 00:44:34,229
and if they can make it
through the storms

378
00:44:34,373 --> 00:44:36,273
this is an ideal home.

379
00:44:48,987 --> 00:44:52,047
Sometimes grebes feed feathers
to their chicks.

380
00:44:52,191 --> 00:44:54,489
This may help bind
the fish bones together

381
00:44:54,626 --> 00:44:58,062
so they can be regurgitated safely
as a pellet.

382
00:45:06,605 --> 00:45:08,903
Young of all kinds have to grow fast

383
00:45:08,974 --> 00:45:11,272
if they're to survive
the coming winter.

384
00:45:14,446 --> 00:45:16,505
The young guanacos build up
their stamina

385
00:45:16,648 --> 00:45:19,242
by playing in the last of
the summer sun.

386
00:45:30,596 --> 00:45:32,928
The mother fox has
only a few more weeks

387
00:45:32,998 --> 00:45:36,161
to teach her cubs how to fend
for themselves.

388
00:45:36,835 --> 00:45:41,738
Carrion from a puma kill gives them
their first taste of red meat.

389
00:45:41,873 --> 00:45:43,602
But meat is a luxury.

390
00:45:43,742 --> 00:45:49,942
To survive they will have to eat insects
fruit, leaves, even grass.

391
00:45:54,653 --> 00:45:55,984
They may be playing now

392
00:45:56,121 --> 00:45:59,557
but in a few weeks they'll
be hunting for real

393
00:45:59,691 --> 00:46:00,919
on their own.

394
00:46:03,428 --> 00:46:07,125
Only the most resourceful can
live through an Andean winter.

395
00:46:10,936 --> 00:46:13,097
All along the chain of the Andes

396
00:46:13,238 --> 00:46:18,540
survival depends on adapting to some of
the harshest conditions on the planet

397
00:46:18,677 --> 00:46:22,545
thin air, bitter cold, relentless wind.

398
00:46:34,092 --> 00:46:35,787
But for those that can live here

399
00:46:35,961 --> 00:46:38,930
the mountains provide all their needs.

400
00:46:53,712 --> 00:46:57,614
Our journey of over five thousand
miles ends here

401
00:46:57,749 --> 00:46:59,512
almost in the Antarctic

402
00:46:59,651 --> 00:47:03,883
where the glaciers of Patagonia plunge
towards the Southern Ocean.

403
00:47:43,762 --> 00:47:46,629
The mighty force of the mountains
can give life

404
00:47:46,765 --> 00:47:47,925
but at any moment

405
00:47:48,033 --> 00:47:49,728
it can take it away.

406
00:47:50,602 --> 00:47:52,433
Living in the Andes

407
00:47:52,571 --> 00:47:55,938
is one of the greatest
challenges in the natural world.