Original subtitles

This is The Americas,

an extraordinary journey across Earth's great supercontinent.

The widest variety of life on the planet.

The untold story...

...of our home.

Tonight on The Americas...

The Andes.

A spectacular sky world

and the longest mountain range

in the Americas.

Forged by fire

and ice.

It's a world of unrivaled beauty.

But here,

life must battle to survive

in the most perilous places imaginable.

The planet's driest deserts.

Frozen peaks.

And strange, magical forests in the clouds.

Every animal

must triumph

in life lived truly on the edge.

The Andes is the spine of South America.

Running from the southern tip of this supercontinent,

it stretches 5,500 miles

forming the high peaks of Bolivia and Peru

before pushing north toward the equator

into the heart of the tropics,

where the mountains of Ecuador

can seem like looking back in time.

Sheer cliffs and deep gorges

are cloaked in forests.

Here, giant higuerón trees,

draped in bromeliads, are fruiting.

And that's exactly what one family

has been waiting for.

Hiding over a thousand feet above the forest,

a spectacled bear mom.

These bears are the rarest in the Americas

and the inspiration for Paddington.

Mom, known by scientists as "Silvestre,"

is nursing her three-month-old twins,

"Yoyo" and "Irene,"

secluded in their tiny nest.

The towering cliffs have kept them safe from predators.

But now the family must leave.

Mom's milk is running out.

They need the fruit

nearly half a mile below.

The sky-high rock face that protected them

is about to become their biggest challenge.

The most dangerous journey of their lives

begins.

Tracked using her collar,

scientists know Silvestre has made this descent before.

But it's the first time for the cubs.

Yoyo and Irene will need to follow their mother closely.

One misplaced step...

...could be a disaster.

Cubs have fallen to their death here.

A moment of reassurance from Mom.

She knows the hardest part is yet to come.

Irene takes a wrong turn.

She has lost sight of Mom.

And at the worst possible moment.

Yoyo has made it down okay.

And so has Irene.

The worst seems behind them.

But there's no time to rest.

Silvestre is bringing them to the very same fruit tree

that she returns to every year.

Plants and fruit like this

can make up over 90% of a spectacled bear's diet,

and the cubs are not holding back.

Spectacled bears navigate these mountains

by having a detailed mental map of their world.

The cubs can stay with Mom for over two years

to build a map of their own.

One day, with luck,

Irene will be able to lead her own cubs

down the same cliffs.

It all seems so easy now,

but the cubs have just undertaken a death-defying start to life.

In the mountains of the Andes,

all life is pushed to the limit.

These remarkable high-rise forests hide other extraordinary secrets.

Spectacular animals so small and fast,

they're almost impossible to capture on camera.

Our journey in the tropical Andes continues,

rising to 10,000 feet,

where the peaks trap moist air from the Amazon,

creating a mysterious cloud forest.

Here, nature is at its most magical.

Curiously-shaped flowers shine out like beacons,

signaling they have energy-rich nectar inside.

If they can entice a visitor,

they will be pollinated.

Usually, bugs do that job,

but these forests are too cold for many of them.

So instead, it's done by...

...hummingbirds.

Most not much bigger than your thumb.

In fact, the Andes is home to more species of hummingbirds

than anywhere else on Earth.

Feisty and agile,

they'll fight to be the first in line for a drink of nectar

on shimmering wings that can beat over 80 times a second.

The Andes has thousands of remote valleys like these,

but just one in Peru

is the home to an almost mythical hummingbird,

hardly ever seen in the open.

He is a Marvelous Spatuletail,

one of just 500 or so left on Earth.

Deforestation has meant their habitat is disappearing.

Only males have these extravagant tail feathers,

which have just one purpose...

to attract a female.

He's keeping them in top condition,

for the performance of his life.

An audience has arrived,

but this is not who he wants.

Rivals.

Every male around, even stumpy-tailed youngsters,

have turned up to fight to control this exclusive courtship area.

He's not the only one who wants the limelight.

Fighting off so many is exhausting.

He really should refuel.

But that's going to have to wait.

A female Marvelous Spatuletail is here.

Now the show can begin.

He'll be judged on the length of his tail feathers

and the quality of his performance.

She's interested.

Time to take his display to the next level.

And now, it's all about stamina.

In this thin mountain air, he's got to dig deep.

It's a critical moment, both for him,

and the future of the species.

If he wins her over,

together, they will produce the next generation.

And at last,

she accepts his invitation.

A sign of hope for this remarkable hummingbird.

Throughout the Andes...

...the land itself can feel alive.

And in a way, it is,

with an eruption occurring every few years.

Immense earth forces forged these mountains...

...leaving a legacy of over 200 active volcanoes...

...more than anywhere else

in the Americas.

For 40 million years,

they've pushed higher and higher.

And in a few places,

an eerie ice world

has formed at the peaks.

Home to a true marvel of nature.

The Andes is so high

that 99% of the world's tropical glaciers are found here.

The largest is in southern Peru.

It's certainly cold,

but at an altitude of 18,000 feet,

ultraviolet radiation is very intense.

So when the sun shines,

the ground heats to a jaw-dropping 111 degrees Fahrenheit,

transforming ice world to sauna in the blink of an eye.

It's the last place to expect to find

a frog.

Marbled four-eyed frogs

live at the highest altitude of any frog on Earth.

Every year, females must breed in pools formed by glacial meltwater.

But their world is changing.

The glacier is retreating further up the mountains.

Each year, she climbs higher,

enduring hotter days,

but also...

...colder nights.

And that's become

a real problem.

The temperature is dropping fast.

She needs to find shelter.

But as her muscles chill,

they are starting to seize up.

The deeper underground, the safer she'll be.

But a clear sky means extreme cold is on its way.

On these nights,

the ice...

is relentless.

Its reach stretches far beneath the surface.

Her journey

looks to be over.

She is frozen solid.

As the world warms up,

something strange happens beneath the surface.

These marbled four-eyed frogs,

living in the highest reaches of the Andes,

have evolved a remarkable talent

almost beyond belief,

and never filmed before.

They can freeze solid

and come back from the dead

every single day.

The only frog in the world that can do this.

She drives forward once more.

The frog that cheats death every night

is ready to continue her journey,

and, with luck, meet a new mate.

This frog may be a miracle worker,

but its future is not certain.

The glaciers on which it and so many other animals depend

are in trouble.

They're shrinking

due to a global rise in temperature.

Over the last 50 years,

the neighboring Qori Kalis Glacier has halved in size.

At the current rate,

it will disappear entirely

in just 30 more years.

Which could be a disaster not just for the four-eyed frogs

but for all life in these mountains.

As water from the sky-high glaciers of the Andes

cascades down the steep slopes,

it creates a unique network of 100,000 rivers.

Water that is crucial both for wildlife

and for millions of people.

Most of these rivers are ice-cold,

but this one in Argentina is near boiling,

superheated by geothermal activity deep underground.

What in their right mind would live in these dangerous waters?

In the mountain rivers of the Andes,

only one animal can master turbulent waters

that range from boiling point to near-freezing.

A torrent duck.

Not just any duck,

but a super duck.

He comes fully equipped...

...with heat-resistant feathers,

armor-plated leg skin,

and built-in protective goggles,

a third eyelid.

This specialist gear means he can survive a daily temperature range

of minus 13 degrees above water

to plus 122 degrees under water.

All to reach a sumptuous buffet.

These superheated waters

are a hothouse for growing fly larvae

in the thousands.

Delicious and nutritious for a duck.

Especially one with a family.

These baby super ducks must find their own food from day one.

Luckily, they are equipped for extreme swimming too.

Tail feathers develop early to act as a rudder,

and huge feet provide propulsion.

Downy feathers trap air to keep them insulated and afloat.

They already have superhero swagger.

But their buoyant down has, well, a downside.

Where the water is deep,

those delicious bugs are out of reach.

They need to find shallower feeding grounds.

But as the family heads downstream,

things get dangerous.

The parents lead the way.

The ducklings can't yet fly.

They will have to swim for it

in these deadly, scalding waters.

Only a third survive to adulthood.

Where they make their jump...

...decides their fate.

As this chick's about to find out.

The parents try to keep tabs on each of the chicks.

But in these raging waters...

...that's not always possible.

As the chick scrambles out,

he must quickly look for another route to get back to his family.

Now...

it's all or nothing.

His air-filled feathers pull him to the surface.

Saved by their superpowers,

the whole family has reached the shallow feeding ground.

A bug buffet

now within reach for all.

If you've got what it takes,

this wild river,

born of fire and ice,

can be a kind of paradise...

...for a duck.

Traveling south, the Andes spread to their widest point.

Here, the highest peaks block moisture from both the Amazon and the Pacific,

which helps create a desert like no other,

the Atacama.

The driest place on Earth.

so arid that NASA uses it to test equipment destined for Mars.

But in exceptional years,

a miracle of nature changes everything.

The Atacama Desert in northern Chile is the driest on Earth.

But maybe once a decade,

a stormfront from the west

can have enough power to reach around the mountains...

...and bring salvation.

Torrential rain.

Summoning one of the rarest wonders in nature.

What is known as a "superbloom."

Billions of seeds that have been sleeping in the sand,

some for more than ten years,

can finally burst into life.

This new world draws strange creatures from beyond the desert.

The coruro, a mountain rodent,

seldom seen on the surface.

A giant caterpillar-hunting wasp

brings food to her young.

And like the rest,

a family of burrowing owls

packs a whole lifetime

into these few weeks of plenty.

Because as fast as the superbloom emerges,

it's reclaimed by the desert.

And life begins the long wait for water once more.

Just to the north is Salar de Uyuni,

the largest salt flat on Earth.

When the rains reach here...

...another brief wonder of nature is created.

A giant mirror

larger than Yellowstone,

set beneath the clearest skies on Earth.

Here, we look into deep space

for answers light-years away...

...while an exquisite vision of the universe

comes to our feet.

But it, too, doesn't last long.

And soon, all that remains is a salt crust,

a world utterly hostile to life.

And yet, for some, it's home.

A salt flat lizard.

A young male on the lookout for a territory.

There's no time to waste.

An oasis?

No.

This water is full of salt.

He can't drink it,

but these brine flies can,

converting it into freshwater inside their bodies.

It's a perfect combo meal.

A drink...

with a side of flies.

But for a rookie,

this is going to take some practice.

Two hundred flies contain just a thimble of water.

He's sure got his work cut out.

Almost there.

Nailed it!

Could life get any better?

Maybe it can.

It's a female salt flat lizard

wafting a powerful, seductive scent into the air.

What young flycatcher could resist?

But all is not as it seems.

Another male.

She will only mate with the strongest males,

dominant enough to hold the precious waterfront territories.

And she wants to see what the young flycatcher is made of.

She's set him up.

It's trial...

...by combat.

Overpowered,

and now in deeper trouble than he knows.

Every inch of the water's edge

is controlled by paired-up power couples...

...who won't share.

Retreat is his only option.

He's not ready to take on the big males right now.

But he is alive

and has learned valuable lessons.

Well... maybe.

Reaching the highest point in our whole Americas journey,

we ascend to over 19,000 feet,

where the salt flats become salt lakes.

Each one a unique, toxic cocktail of metals, minerals, and microorganisms.

The most extraordinary of all is Laguna Colorada,

a hellscape where morning ice has a daily battle

with the strongest UV radiation on Earth.

More than double that of Death Valley.

And yet, every year,

it's home to the most spectacular event in the Andes.

The Toxic Red Lake of the High Andes.

It takes a special kind of toughness to survive here.

But once a year, this lake becomes the setting

for the greatest party in the Andes.

Although not everyone is invited.

Right now, this world of extremes

plays host to James' flamingos.

They gather here from across the Andes

in the thousands

hoping to find a mate.

Males and females might appear almost identical,

but they know the difference.

They all want to look their best,

and the pinker the better.

The secrets to their success?

Tough-skinned long legs

letting them wade through the caustic lake.

And a unique bill that filters out microscopic life from the toxic water.

Eating this food turns their feathers pinker,

making them more desirable.

But life is about to get more complicated

as the Laguna becomes "Flamingo Central."

Chilean and Andean flamingos are flying in too.

Both much bigger, but...

...a lot less graceful.

Crowds begin to build to 40,000 strong.

And then, on an unseen cue,

a dance-off begins.

The smaller James' are in danger

of being pushed out before it even begins.

Over four feet tall,

the Chileans can strut in the deep water...

...while the enigmatic Andeans

rumba by the smoke machine.

But at last, the James' get their groove on too.

A tango at the top of the world.

These courtship dances last for weeks.

One by one, lovers unite...

...as eventually they find a mate.

But until then, the dance continues.

The greatest show in the greatest mountain range

in the Americas.