Original subtitles

At the southernmost tip of the world, a new life is beginning.

After nine weeks in this egg, balanced on Dad's feet, Emperor Penguin Chick,

Pico, gets his first view of the outside world.

And of his doting dad.

There's no tougher place to start life.

With temperatures down to minus 35 degrees, and wind speeds up to 150 miles

per hour, Pico's home is one of the most hostile on the planet.

Three grueling months of winter lie ahead.

Pico must stay glued to his dad's feet at all times.

Or he'll freeze to death in minutes.

And there's another looming threat.

The stored baby food from Dad will only last one more week.

Pico desperately needs his mom to return with fish soon, to stay alive.

For many babies born wild, growing up in a hostile

home means every day is a fight to survive.

This sun-scorched valley in Central Africa is home to 10-month-old lion cub, Minnie.

She's the baby.

She's the baby.

The smallest of four teenage cubs.

And the most affectionate.

Her pride dotes on her.

But Minnie's life is under threat.

Five miles north of her mother's home.

Three nomadic males have just crossed into the family's territory.

If they take over the pride, they will kill any cubs.

So they can father their own.

As the youngest, Minnie is most vulnerable.

But right now, she has a more urgent problem.

In the 100-degree heat, prey is scarce.

And the family hasn't eaten for days.

At last, Minnie's mom spots a chance.

All six females are masterful hunters.

But sneaking up on prey with no cover to hide in...

is nigh on impossible.

Like so many previous attempts this week, it ends in failure.

Once again, malnourished Mini will go hungry.

All her family can offer is comfort.

In some hostile homes, the challenges are easy to see.

In others, first appearances can be deceptive.

This little arctic fox pup is Silva.

She's six weeks old.

And unfortunately for her, the only girl among three unruly brothers.

She's all for a quiet life.

But in this family, that's just not on the cards.

The boys might have the brawn.

But Silva definitely has the brains.

Today, her mum's keeping an eye on her boisterous brood.

While their dad is out hunting.

Bothersome brothers aside, it looks like an idyllic place to grow up.

But in fact, Silva's island home is one of the most hostile on the planet.

Close to the arctic circle, it's topped by glaciers.

And surrounded by icy seas.

With notorious undercurrents.

Weather here can change in an instant.

Bringing gales.

Sudden storms.

And landslides.

And that's not even the biggest threat.

In a few months, it'll be winter.

Temperatures will plummet below freezing.

And by then, Silva and her brothers will have to fend for themselves.

The pups must fatten up fast.

Though that's easier said than done.

Their main food is migrant birds.

But their nests are in other fox territories.

With extremely hostile owners.

Silva's desperate dad sneaks onto his neighbour's land.

It's a risk.

But it's not easy.

But he can't let his family starve.

As Silva's dad approaches the nesting cliffs.

His neighbour spots him.

And heads straight for him.

The neighbour is triumphant.

Silva's dad is lucky to come away unharmed.

He must continue his search for food elsewhere.

The pups are getting hungrier.

But however much the boys pester their mum.

She has nothing to give them.

Silva is more like her dad.

Faced with a problem, she tries to solve it herself.

There just might be something to eat if you look hard enough.

But

determination alone is not enough to survive.

The hostile winter ahead.

On the other side of the world, Pico faces the same fate.

His life depends on his mum's return.

And thankfully, his wait is nearly over.

After two months at sea, Pico's mum is finally heading home.

With a belly full of fish to feed her son.

It's a mammoth four-day trek across sea ice to reach home.

Pico's mum is determined to get there.

Just as dad's food store runs out.

The family is reunited.

And Pico's dad reveals their little bundle of joy.

Pico is carefully swapped from one doting parent to the other.

And given a much-needed meal.

After one last look at his son.

It's dad's turn to make the epic journey to sea.

To stock up on supplies for Pico.

With both devoted parents working as a tag team.

It doesn't take long for Pico to more than double in size.

His mum's feet don't seem quite as big as they used to.

He should now be mixing with other chicks his age.

But Pico is in no hurry to leave his mum.

Time for a little persuasion.

Cautiously he approaches two chicks on their own.

But they don't seem keen to make friends.

No chick finds it easy to stand on their own two feet.

But there comes a time in each one's life.

When they have to be brave.

And for Pico, that time is now.

His mum is going to sea.

And leaving him in a nursery for the very first time.

First days are always daunting.

And he hasn't been apart from mum or dad since he was born.

With his mum's gentle encouragement.

This little chick takes his first big step to independence.

One last glance back at mum.

And Pico is accepted into the gang.

From now on he'll spend weeks at a time.

In the world's coldest boarding school.

Huddling with his new found friends.

For walks.

Pico couldn't have had a tougher start in life.

But thanks to his parents' tireless efforts.

He's made it to spring.

Soon he'll be strong enough to fend for himself.

Out at sea.

With parents as devoted as Pico's.

Even the coldest homes can feel warm.

In Iceland, the weather is beginning to turn.

Winter is coming.

And Silva and her brothers urgently need to put on weight.

Silva's mum is scavenging what she can.

But it's not enough to fatten up four pups.

With pushy brothers.

Silva gets almost nothing.

Resourceful as ever.

She's finding other ways to keep hunger at bay.

Crowberries.

Small but nutritious.

And that's not all she's spotted.

In the distance.

Her dad has made a big discovery.

A bay full of birds.

That belongs to no one.

But a fast-flowing icy river stands between

him and the answer to his family's problems.

The river.

He plucks up courage.

And takes the plunge.

Arctic foxes are not natural swimmers.

This is a last resort for Silva's dad.

First hurdle over.

Now.

For the reason he's here.

In his desperation.

Silva's dad blows it.

He tries another tack.

He has plenty of enthusiasm.

What he needs is stealth.

On the opposite bank.

Silva takes it all in.

Her dad's not giving up.

Finally.

His persistence wins out.

Silva's first decent meal in weeks.

All to herself.

But her dad has three hungry boys too.

He rings the dinner bell.

The boys arrive as dad takes the plunge for the second time.

Silva knows she won't get a look-in when her dad brings back the next meal.

There's only one thing for it.

She's never swum in her life before.

But Silva does the seemingly impossible.

Braving icy water and strong currents.

To follow her dad.

Before Silva reaches the other side.

Her dad makes his second kill.

At last.

A good-sized meal for his sons.

While the boys wrestle it out between themselves.

Across the river.

Silva stays focused.

A kitty wake.

Distracted by a falcon.

It's Silva's chance.

She's done it.

Even the falcon she takes in her stride.

Her first-ever kill.

Still, between

them, Silver and her father have changed the family's fortunes.

They have all the skills they need to survive the winter red.

It's true some things never change.

After all, you can't have brothers and not expect to be teased.

But Silver has proved that she's one exceptional sister.

Who's got what it takes to make it in her hostile home.

On the dried out plains of Zambia, baby of the family Mini is weak from

hunger and struggling to keep up with her pride.

The family has at last bagged a small meal.

Their first in four days.

Mini finally catches up.

But she's not confident or pushy enough to muscle in.

Lions need courage.

And Mini must learn to be much more assertive.

If she's to survive.

Especially as her home has just become more hostile.

A mile up river.

The nomadic males are moving in.

Scent marking is a sure sign that they mean to take over.

The intruder's roars are a red flag for Mini's family.

They must get the cubs into hiding before dark.

Especially Mini, whose life has never been more in danger.

To be continued...

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