Original subtitles

.

Narrator: when you see this Symbol, you know you're watching

Television that's educational And informational.

The more you know on nbc.

Dylan: hi there, I'm dylan Dreyer.

Whether it's a flock, a herd, or A troop, some animals are just

Happier together.

Come join the crowd as we meet Extraordinary wildlife, right

Now on earth odyssey.

Today, a marathon migration Proves that running with the

Herd pays off.

And it takes more than cuddle Power to keep these mountain

Monkeys warm.

Plus, in this town, birds of a Feather really do flock

Together, by the tens of Thousands.

And a silent predator sweeps Across the ocean floor, trying

To defeat a crustacean army.

All that and much more, right Now on earth odyssey.

[music]

Dylan: in nature, some animals Are mostly loners, coming

Together only to mate Or to fight rivals.

But others, like elephants, Dolphins, and primates, are born

Into complex social groups.

It seems there's both strength And safety in numbers.

That's especially true for one Species, who's mastered the art

Of going the distance.

In north america, the yukon Ranges provide animals just

Enough sustenance to survive Months of sub-zero temperatures.

This enormous herd of porcupine Caribou have mated through a

Lean winter.

But now the seasons are Shifting.

It's spring, the females are Pregnant, and the caribou have

Grown restless.

They're ready to head north to Their calving grounds.

The porcupine caribou's journey Is the longest animal land

Migration in the world.

More than 200,000 individuals Will run more than 1,500 miles.

They move from the forests of The canadian yukon to the arctic

National wildlife refuge in Alaska.

Called caribou in north america, They're better known as reindeer

In europe and asia.

The herd creates a dramatic Spectacle as they head towards

The greener pastures of their Calving ground.

They thunder across ancient North american trails as they

Have for more than 3,000 years.

This season's weary travelers Arrive to a summer of arctic

Color.

The top layer of the tundra has Melted.

Fresh vegetation provides Essential nutrition for the

Lactating mothers.

Around 40,000 calves are born Each year.

The infants grow quickly.

Amazingly, within a week, the Newborns can run as fast as

Their mothers, more than 45 Miles per hour.

But even in this extreme Environment, specialist hunters

Are watching.

Arctic wolves also prowl the Tundra.

They, too, travel long distances To find food, and they have

Their own offspring to feed.

The youngest caribou are easier Prey.

A mother searches for her calf, But it's fallen behind the herd.

A chase can begin in seconds.

[suspenseful music]

Dylan: but this calf is lucky.

More than 10% of calves will be Taken by predators in the first

Month.

But for those that survive the Summer, a first long migration

Back is beginning soon.

As they learn to run with the Herd, they will face a constant

Battle for food while hoofing it Over miles of terrain.

Predators, like these wolves, Will keep them constantly on the

Move.

But the porcupine caribou seem To draw their vital energy from

The size and momentum of the Herd.

Coming up, find out why grooming And group hugs are key to

Survival at high altitude.

And a massive undersea pileup Has a protective purpose.

Plus, in this town, an ancient Tradition of kindness to animals

Has outsized results.

Find out more when earth odyssey Returns.

.

Narrator: we now return to The more you know on nbc.

[music]

Dylan: high in the mountain Forests of southern china lives

An impressive tree dweller.

There aren't many animals that Can survive the large seasonal

Swings of climate here.

But the golden snub-nosed monkey Thrives at extreme altitudes.

Their home is a small region of The tibetan plateau, between

6,000 to 13,000 feet above sea Level.

In winter, snow falls across the Range, sending temperatures

Plummeting.

It's thought that the monkeys' Noses are snubbed to avoid

Frostbite.

Tfood becomes extremely limited Once the fruit, nuts, and leaves

Are gone.

So the monkeys must live off Lichen, moss, and bits of bark.

Intensely social and cooperative As these monkeys are, they still

Have to find ways to cope with Rivalry for food and mates.

As the seasons change, scarce Resources breed intense

Competition.

Males tend to live alone or Sometimes in all-male bachelor

Groups.

But those with families have a Busy job keeping everyone fed

And happy.

This species spends most of its Time in the trees.

But down on the forest floor, a Brawl is brewing.

A young challenger wants to take Over one dominant male's role

And breeding privileges.

Bearing his razor-sharp teeth, The dominant male tries to scare

Off the challenger.

But the younger male persists.

[music]

[screeching and fighting noises

Dylan: the group is whipped into A frenzy as their leadership

Hangs in the balance.

Luckily, this battle is mostly Bluff and bravado without any

Physical harm.

The challenger retreats to fight Another day.

Although the males compete for Dominance in front of the whole

Troop, it's the females who Ultimately choose their own

Partners.

And he'd better be good at Grooming.

Their thick coats require Constant care in this weather.

If the females lose interest or Grow cold to his caretaking and

Advances, he'll become the Target for a takeover.

And as loyal as they may appear Now toward the alpha male, some

Females will also find other Partners.

It's a clever strategy since Male monkeys will protect their

Own genetic line.

[monkey shrilling]

Dylan: family ties are a good Hedge to keep little ones from

Harm.

All this bonding and social Cooperation help keep the whole

Troop healthy in the remote Forests.

Their offspring won't mature for Six or seven years.

Enough time to learn the key Life lessons of this reclusive

And endangered species.

Coming up, queen marie Antoinette named this bird for

Its elegant moves.

And it's a decapod decathlon When these sea creatures take

Off.

Find out more when earth odyssey Returns.

.

Narrator: we now return to The more you know on nbc.

[music]

Dylan: the mystery of bird Migration fills me with a sense

Of wonder.

Great flocks travel thousands of Miles in harsh conditions to

Arrive at precise locations.

We don't exactly know how birds Decide when and where to stop on

Their journeys, but one species Has adopted a layover in its

Flight path thanks to some very Attentive humans.

One species of unexpectedly Elegant birds undertake an

Intense migration loop every Year.

They'll cross the himalayas from Mongolia to the edge of an

Indian desert and return by Another arduous route.

More than 45 years ago, a dozen Demoiselle cranes stopped on

Their way in the small indian Town of kichin.

The locals gave the birds grain And water.

Now, more than 25,000 cranes Come back every year.

So many that you could say the Town has been overrun by its

Kindness to animals.

The area has become a key Migratory destination as water

Fills local ponds after the Monsoon rains.

And with locals and visitors Continuing to pay for the grain

To feed them, some flocks stay For up to five months.

They are honored avian guests in A man-made refuge that's likely

To increase in popularity.

Coming up, their legs are nearly Two feet long, and they'll need

Every inch when trying to evade A stealth predator.

Find out what happens next when Earth odyssey returns.

.

Narrator: we now return to The more you know on nbc.

[music]

Dylan: in the southern pacific Ocean off australia, one

Species is rising from the Deep, step by step in a huge

Formation.

With more than 25-inch legs, the Japanese spider crabs are among

The largest crabs in the ocean.

A tough outer shell is a perfect Defense against predators.

But this invertebrate's outer Shell is totally rigid.

So as the soft crab grows, they Also outgrow their outer bony

Armor every year.

Now they've come up from depths Of more than 2,500 feet to molt.

One female has reached the final Stage.

Her body has been pumping out Enzymes to separate the old

Exoskeleton.

It will take her an hour to Literally climb out of her

Shell.

Migrating en masse, spider crabs Have safety in numbers.

But she's been left behind.

She needs to be quick.

Predators have been waiting for The migration.

[music]

Dylan: an easy target, she needs To get back to the group.

Hungry, smooth stingrays are More than 13 feet in length.

But mid-molt, the crab can't Move.

Another straggler, it's Instantly targeted.

Immobile, the molting crab could Be next.

She gets lucky.

She's managed to wriggle free of Her old shell, but her new,

Lighter-colored shell will take Days to harden.

At nearly 800 pounds, each ray Will eat multiple crabs.

Getting to the bottom of the Pile is the key survival

Strategy.

Crabs that still have their old, Tough shells act like living

Shields.

It takes 48 hours of the Onslaught to survive before her

Shell fully hardens.

The marching crabs will leave Behind what looks like a

Graveyard.

But the decaying exoskeletons Signify the next stage of a life

Cycle.

We've seen how very different Species have evolved to depend

On each other around the world.

From the longest land migration On earth in north america to a

Flight across the tallest Mountains in the world, animals

Share rewards and challenges to Protect their own species.

Thanks for watching.

I'm dylan dreyer.

See you next time on earth Odyssey.

[music]