The Dinosaurs

In the depths of space,

a threat is looming.

Trapped between the orbits of Jupiter and Mars…

the asteroid belt.

One and a half million chunks of ancient rock,

circling the sun.

Drifting endlessly.

But, in a single moment of pure chance…

…one asteroid is thrown out of its orbit.

A fleeting instant,

millions of kilometers from Earth,

sends it on a new trajectory

towards the very center of our solar system.

But its journey will come to a sudden and violent end,

in one of the most catastrophic events in Earth's history.

And the final chapter

in the epic story

of the dinosaurs.

It's three million years

since the asteroid started its journey towards Earth.

And the dinosaurs rule the planet.

They dominate the land and are now entering the ocean as well.

The high sea levels have split North America in two…

creating endless coastlines…

hundreds of tropical islands…

and opportunity.

But these islands are no paradise.

They are home to a formidable predator.

One of the fastest, most agile dinosaurs of its kind.

North America's answer to the Spinosaurus.

Just not in the way you would think.

Not even remotely.

This is Hesperornis.

He is formidable, and he is fast.

But he's pretty much the opposite of his giant, terrifying cousins.

He's awkward…

…and clumsy.

And has tiny teeth.

Not exactly the traits of a ferocious hunter.

But what he does share with Spinosaurus

is that he's not confined to dry land.

In fact, he's the most advanced aquatic dinosaur in history.

Like some sort of prehistoric penguin,

he's able to swim far out to sea to access feeding grounds

that were previously out of reach.

This is the bounty of his new blue realm.

Down here, his big clumsy feet become powerful propellers.

And his 94 needle-sharp teeth snatch fish with ease.

But as an air-breather,

he's still tied to the surface.

And the surface is not a safe place to linger.

Because below,

there are beasts

twice the size of a killer whale.

Mosasaurs.

The apex predators of these seas.

Hesperornis must get back to the shore.

But the mosasaur moves with frightening speed.

Luckily, Hesperornis is much more agile.

But he's exhausted.

Which gives the mosasaur one last shot.

Hesperornis is a true survivor,

venturing further into the ocean than any dinosaur ever has.

But these waters are treacherous, even for the best swimmers.

Despite the dinosaurs' success in the shallows,

the mosasaurs

rule the waves.

Eight hundred miles north, on land,

it's a different story.

Fueled by a warm, stable climate,

the dinosaurs' dominance here is unrivaled.

The great sauropods are thriving among the tall trees,

as they have since the dawn of the Jurassic.

But down below, there has been a revolution.

A female hadrosaur.

While she may be dwarfed in present company,

she's actually larger than an elephant.

And she won't be held up by these giants,

because nothing can stop a mother on a mission.

And that mission

is to feed her family…

who are somewhere

down there.

Long ago, their cheek-stuffing ancestors were scarce and scattered.

But hadrosaurs are now so successful, their herds are thousands strong.

The greatest gatherings of dinosaurs the world has ever known.

But this female's family isn't traveling with the herd.

There, in the safety of the crèche,

a sprawling nursery for hundreds of young hadrosaurs…

…including her own.

At six months old, they have insatiable appetites,

and will eat almost anything she brings them.

Anything.

Feeding in this bird-like way takes a lot of refills,

so she's constantly leaving to go find food.

And when moms are away,

little ones will play.

With the wingspan of a fighter jet,

pterosaurs are now bigger than ever.

And crèches are the perfect hunting grounds,

where unguarded nests are the easiest pickings.

Despite the threat from this towering monster,

the mothers will defend their babies at all costs.

But the giant pterosaur is determined to feed.

The screams from the nest are like a dinner bell to the predator.

But the little ones aren't just crying in fear.

They're calling for help.

This fierce instinct to protect their young

is central to the hadrosaurs' remarkable success.

But other dinosaurs are taking defense to a whole new level

because the arms race between predator and prey is escalating.

And this will give rise to the most iconic dinosaurs of all time.

This will take so long

that the continent of North America will shift,

the land buckling up into the sky.

The Rocky Mountains.

It's here, in the foothills below,

that the dinosaurs are making an impact.

Pachycephalosaurus.

Using their outrageously thick skulls…

to duel for supremacy.

And alongside them,

a dinosaur with even more impressive headgear.

Triceratops.

She may look like a rhinoceros,

but she's twice the size of one.

And armed with spear-like horns over one meter in length.

Triceratops and Pachycephalosaurus have impressive weapons.

Yet there are some here

that are even more armed and dangerous.

Under the cover of darkness,

the latest and greatest of the armored warriors.