Prehistoric Planet

Surely, one of the most remarkable animals that has ever existed,

and certainly one of the most famous, is a dinosaur.

Tyrannosaurus rex.

An animal to spark the imagination for all of us.

What kind of an animal was it?

What did it look like? How did it live?

Now, scientific research has answered such questions.

And not just about T. rex,

but the other species that lived alongside it.

And the latest imaging technology enables us to bring them all to life.

Planet Earth, 66 million years ago.

The skies are filled with flying giants.

In the seas, monstrous reptiles patrol the depths.

And on land, dinosaurs of every kind,

all facing the struggle to survive.

We now know so much about a world that was ruled by the dinosaurs.

This is their story.

For millions of years, the lands of planet Earth

have been carved by water.

And the rivers that flow here are still shaping these great canyons.

Such places are the home of flying reptiles.

Pterosaurs.

Their wings of skin stretch from finger to ankle.

And they can fly for hundreds of miles in a day.

Each evening,

they come to this canyon in huge numbers to roost on its narrow ledges.

There is safety in numbers.

And anyway, few land-living hunters venture here.

But one does.

A type of dinosaur. Velociraptor.

Their bodies are kept warm by feathers, but they can't fly.

They are, however, exceptionally agile.

And just as well.

One false step here could bring disaster.

The pterosaurs are skittish.

They will take to the air at the first sign of danger.

If the Velociraptors are to get a meal, the element of surprise will be crucial.

Lightweight bodies and feathered arms help them

to control their descent.

And their broad tails assist them in keeping their balance.

Those pterosaurs that are resting on the margins

of the colony will be the easiest targets.

The roar of the waterfall drowns the sound of slipping rocks.

The female goes high.

The two males stay low.

A few pterosaurs are almost within striking distance.

She has one, but now the whole colony is alarmed.

In the chaos, her victim slips from the ledge.

The female puts the effectiveness of her feathered tail to the test.

And, in the end, she gets her meal.

The males are left to face the pterosaurs.

The power of fresh water is at work all around the planet.

Global temperatures are high.

There are violent storms and torrential rains.

Much of North America is covered by thick, lush forest.

Here live some of the most gigantic plant-eaters that have ever existed.

And they, in turn, are prey for the most ferocious of hunters.

Tyrannosaurus rex.

This old male has just brought down a Triceratops.

But in doing so, he's been injured.

T. rex are built for hunting large herbivores…

though many of those have evolved heavy defensive weapons.

Decades of battling armored prey has scarred his body.

One battle even cost him the tip of his tail.

These new injuries are more serious.

At his great age, infection is a real risk.

River water could help to clean his wounds.

He stands a good chance of living to fight another day.

But that day could come sooner than expected.

Another T. rex.

A stranger.

But this newcomer has a different smell.

It's a female.

She's younger and smaller.

But nonetheless, she might also be a rival.

He, however, makes it clear that he's not interested in fighting.

He would prefer to mate.

She seems to approve.

The facial area of a tyrannosaur is very sensitive to touch,

and they nuzzle.

His great size and his battle scars are evidence that he is a survivor.

And that perhaps, in her eyes, makes him an attractive partner.

So, they stay together.

And in the coming weeks, they mate frequently.

Eventually, she'll lay up to 15 eggs.

And with them comes the promise of the next generation.

Habitats that depend on fresh water can change rapidly and radically.

In parts of central Asia,

heavy seasonal rains fill the rivers until, eventually,

they overflow their banks.

The surrounding plains are flooded.

And through the water wades one of the most bizarre of all dinosaurs.

Deinocheirus.

It's even taller than T. rex.

And its massive duck-bill snout is very effective

in gathering water plants.

This male feeds voraciously,

having eaten very little during the long dry season.

Water plants are rich in nutrients.

And his huge, curved claws, eight inches long,

enable him to dredge them up from deep beneath the surface.

He himself is a source of food for smaller creatures.

Bloodsucking flies, which infest his coat.

They're irritating and even painful.

And while his huge claws enable him to have a good scratch…

there are always some spots that are just out of reach.

To get to them, he needs assistance.

A dead tree. That could be the answer.

That's much better.