Fight for Life Planet Dinosaur

We are living through

THE golden age

of dinosaur discoveries.

From all over the world,

a whole new generation of dinosaurs has been revealed.

From the biggest giants...

..and the deadliest killers,

to the weird and wonderful.

From the Arctic

to Africa.

From South America to Asia.

Using the latest evidence,

for the first time

we have a truly global view of these incredible animals.

This time,

we journey back 150 million years

to the Jurassic Period.

A time when the first giant killers stalked the earth.

But these giants weren't confined to the land.

Recent discoveries

have revealed an astonishing new hunter in the oceans.

These new giant killers posed the greatest of threats.

With the smallest advantage tipping the balance between life and death,

predator and prey were locked in a perpetual battle for survival.

DINOSAUR ROARS

To understand this world,

we must travel back 150 million years

to a time when much of Europe looked like the Bahamas.

A time when these warm tropical seas were home to giant predators.

Some of which, have left their mark

etched in stone.

This cliff face in Switzerland

is carved with a series

of enormous gouges and grooves.

Many over nine metres long.

The entire rock face is actually

one huge fossil,

an upturned slab of Jurassic Ocean floor.

And the marks were left by a predator

as it hunted for food.

Sharks like this squatina

are similar to angel sharks which still exist today.

It's an ambush predator and lies in wait.

But in these seas there are bigger hunters.

This is Kimmerosaurus.

They belong to a group called plesiosaurs.

At six metres long,

they're one of the Jurassic Ocean's most successful hunters.

And also one of the most common.

And it's this unusual hunting method

that left its trace on the ocean floor

We now know that the rock face in Switzerland

is etched with the marks of hunting plesiosaurs.

But these giants were not the king of the seas.

Many of the fossils show evidence of having been violently ripped apart.

Clearly, there were

much, much bigger predators

lurking in these seas.

In 2008, in an island in the high Arctic,

a fossil was dug out of the frozen earth.

Its skull alone was nearly twice that of T-rex.

This was an enormous killer.

A killer, the like of which had never been seen before.

More than 15 metres long,

and weighing about 45 tonnes,

this is the most powerful marine reptile ever discovered.

Twice as big as most Jurassic Ocean predators...

..this is Predator X,

an animal

that must go down in history as one of the ocean's most deadly hunters.

And it's prey like Kimmerosaurus

that are in its sights.

Skull analysis of giant killers

like Predator X,

suggests that they hunted their prey by smell...

..channelling water through special internal nostrils,

allowing them to silently hone in on their target.

By analysing their anatomy,

we've calculated that Predator X

could move up to five metres per second -

fractionally faster than a Kimmerosaurus.

The kimmerosaurs only defence

is to head for the refuge of shallow water.

This time, Predator X's size works against him.

Unable to hunt efficiently in shallow water...

..means that the Kimmerosaurus can use this as a refuge.

A subtle advantage that makes the difference between life and death.

Predator X and Kimmerosaurus

are just one example

of a predator-prey relationship

locked in a fight for survival.

In the western states of North America

is one of the richest sources of dinosaur fossils.

It's known as the Morrison Formation.

Recently, these rocks

have given us a tantalising glimpse

of how two dinosaurs adapted together

to protect themselves against another deadly predator...

..Stegosaurus and Camptosaurus.

Fossils of these two species

are almost always found

in the same area.

In 2008,

footprints of the two

were recovered from the same site.

It seemed that they lived alongside one another.

But why would two unrelated plant-eaters

live together?

Stegosaurus -

a heavily armoured tank

with a deadly weapon at the end of its tail...

known as a thagomizer.

Camptosaurus - a much smaller plant-eater

with no obvious defences.

DINOSAUR GROANS

Skull analysis shows

that Camptosaurus has bigger eyes -

and relative to its body - a much bigger brain.

Camptosaurus appears to be a lookout.

While the armoured Stegosaurus provides the muscle.

STEGOSAURUS GROANS

It's likely Camptosaurus and Stegosaurus

stuck close together for mutual protection...

..in a world where danger is ever-present.

CAMPTOSAURUS CROWS

CAMPTOSAURUS GROANS

CAMPTOSAURUS CROWS

CAMPTOSAURUS CROWS

CAMPTOSAURUS CRIES

ALLOSAURUS GROWLS

Allosaurus -

a one-and-a-half-tonne ambush hunter with a lethal bite.

The world had never known a predator like it.

But having lost the element of surprise,

it's now faced with the prospect of either starving...

or facing the most well-protected giant of the Jurassic.

ALLOSAURUS GROWLS

STEGOSAURUS BELLOWS

Virtually impregnable from behind,

a predator needs to try to attack the stegosaurs from the front.

ALLOSAURUS GROWLS

ALLOSAURUS ROARS

STEGOSAURS BELLOW

STEGOSAURUS HOWLS

STEGOSAURUS BELLOWS

ALLOSAURUS PANTS

The evidence for encounters such as these is incredible.

Fossil finds of 2005,

directly link

these two great animals in battle,

revealing the unmistakeable signs

of injury.

A Stegosaurus back plate

was discovered

with a u-shaped bite taken out of it.

A bite mark that fitted

the Allosaurus' jaws perfectly.

Even more amazing

was an Allosaurus vertebra.

It had a massive impact wound.

The wound appeared to have been made

by a Stegosaur's thagomizer.

The blow being so powerful

it punched a hole in the bone

of the Allosaurs' spine.

What's more incredible

is that the injured bone shows signs of healing.

This Allosaurus survived.

The balance of power between predator and prey is a fine one.

Prey continually evolve

different strategies

to avoid predators.

Both with their bodies,

like Stegosaurus,

and their behaviour

like Camptosaurus.

And in the Jurassic oceans, we have evidence to suggest

that plesiosaurs protected their young...

..by finding sanctuary in shallow water nurseries.

But such lagoons

won't always deter a hunter.

And a rising tide gives this predator a glimmer of hope.

PREDATOR X ROARS

But in this shallow water,

the huge Predator X can't use its power.

The smaller, agile Kimmerosaurus

can easily outmanoeuvre

the lumbering killer.

However, the Kimmerosaurus can't permanently protect itself

in this sanctuary.

They need to venture into deeper water to feed.

And that is where Predator X has the advantage.

Successful predators need to play a waiting game.

ALLOSAURUS GROWLS

Allosaurus is the most common killer in these lands.

Nine metres long,

with a battery of saw blade-like teeth

and powerful, clawed forearms -

Allosaurus is a formidable hunter.

ALLOSAURUS GROWLS

It shares the plains

with dozens of species

of plant-eating dinosaurs.

A lone Camptosaurus, away from the protection of Stegosaurus...

..should be easy pickings for a hunting Allosaurus.

Allosaurus teeth were serrated front and back,

perfectly evolved for tearing through flesh.

However, recent research has indicated

that Allosaurus' bite was surprisingly weak.

Calculations suggested its bite was less powerful than a lion's -

despite being seven times more massive.

So, just how did this Jurassic monster

hunt and kill?

The answer is with an element of surprise.

Camptosaurus relies

on its keen senses to avoid predators.

Allosaurus on the other hand,

is a fast and powerful ambush hunter.

Faster than Camptosaurus.

A one-and-a-half-tonne killer can't run fast for long.

It's a question of speed versus stamina.

CAMPTOSAURUS SHRIEKS

ALLOSAURUS ROARS

ALLOSAURUS ROARS

Despite the apparent weakness of its bite,

Allosaurus did in fact have a deadly killing method.

Its skull could withstand a force

more than 15 times as great as its bite.

This meant that Allosaurus used its head like an axe.

Its strong neck muscles driving its top jaw into its prey.

With every impact, the serrated teeth

would tear through its prey's flesh.

The victim dying, through a combination of shock and blood loss.

It isn't pretty, it isn't clinical...

but it's ruthlessly efficient.

However, making a kill

never actually guarantees a meal.

Because here,

Allosaurus isn't the only killer in these parts.

DINOSAUR ROARS

Saurophaganax.

At 12 metres, it is the biggest carnivore in the region.

SAUROPHAGANAX ROARS

And one of the advantages of being so big

is that stealing another's kill is that much easier.

Giant predators like Saurophaganax and Allosaurus

used their power and size to dominate their domain

and all those within it.

And the story was no different in the Jurassic oceans.

These are the bones of Plesiosaur.

They appear to have been broken into fragments.

And many of these show indications

that they didn't die of natural causes.

It looks more like they were violently dismembered.

One particular fossil gives us a chilling idea

of how these plesiosaurs might have been killed.

It consists of a skull

with a few vertebrae still attached

but nothing else.

All these dismembered fossils

were found in deeper waters,

where plesiosaurs need to feed

but where they're in the greatest danger.

This animal is in the worst possible place -

hunting alone at the surface,

where it's most vulnerable to attack from below.

In deep water,

Predator X can use its full power.

Although, injured and stunned

this plesiosaur is armed with a vicious bite.

So, Predator X still needs to be wary.

Severely wounded, now the only sanctuary

is the shallow water of the nursery.

Predator X's bite is formidable,

estimated to be four times that of T-rex.

Biting hard, it perforates the body,

cutting through muscle and bone before shaking it to pieces.

It's almost certain that the bite marks on the fossil plesiosaur

were made in this way.

And the position of the marks also indicated

the attack came from below.

The never-ending battle

between predators and their prey

is a finely balanced one.

However, for the most successful and enduring predators,

the struggle to survive is always tipped in their favour.

And predators like Predator X,

a killer with one of the most powerful bites ever known...

ruled the oceans for more than 100 million years.

Subtitles by Red Bee Media Ltd

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