Attenborough and the Sea Dragon Page #4

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is damaged and here, too,

and also on some of these belly ribs

so I think there's a bite

which goes right across here.

That probably reflects the width of

the skull of the animal that bit it.

Yeah, yeah. So it came

in across here, almost.

Somewhere like that, yeah.

There was a massive bite, it

caused catastrophic injury

and, remember, the ribcage

is protecting lungs.

This was an air-breathing

marine animal and as a swimmer,

these lungs are vital not just for

breathing, but for its buoyancy.

So, once this ribcage is punctured

and the lungs are punctured,

this animal is dead.

It can't breathe

and also it's going to sink straight

down to the sea floor as well.

It's quite likely that the

animal that killed this animal,

presumably it was looking for food,

it didn't get to eat it.

Oh, no, I think it just killed it.

It didn't eat it, or else

it wouldn't be so intact.

So this probably all took

place in the surface water,

but as soon as it's done this injury,

this thing just sank like a stone

straight down to the sea floor

and then it was lost to the

animal that was trying to eat it.

So, it looks as if Chris'

attack theory might be right.

But what type of creature

could possibly have inflicted

so much damage to our sea dragon?

A rather unusual fossil in Chris'

collection might give us a clue.

This is fossilised ichthyosaur

droppings called a coprolite

and what makes it particularly interesting

is that within this piece of

dung, you can see fish scales.

So, that shows that

ichthyosaurs were fish eaters,

but more than that, this one

is even more interesting

because in this piece of dung, there

are teeth - ichthyosaur teeth.

So, the animal that produced this

was almost certainly a cannibal.

It ate other ichthyosaur species.

Could it be that our dragon was

killed by one of its own kind?

To find out more,

I've come to the Natural History

Museum of Stuttgart in Germany.

Here, they have one of the most impressive

and varied collections of

ichthyosaurs in the world.

They came in all shapes and sizes,

but of all the ichthyosaurs that

existed 200 million years ago,

there was one which was

particularly fearsome.

This is temnodontosaurus,

one of the biggest of the sea

dragons so far discovered.

They grew up to 10m long

and individual bones have

been discovered which suggest

that they could grow even bigger than that.

The remains of these

terrifying sea monsters

were discovered in a quarry

just outside Stuttgart.

These are the biggest complete

temnodontosaurus fossils ever found.

This huge predator had the

largest eye known of any animal,

which would have given it

extremely acute eyesight.

Not only that, but the eye was surrounded

by a ring of scutes - bony plates...

to protect it from the

water pressure at depth.

So, with eyes the size of footballs,

this monster was able to hunt at

all depths of the Jurassic ocean.

It also had rows of sharp teeth

that would have allowed it to

rip apart almost anything.

These teeth are shaped like blades,

well suited for cutting into flesh.

And here's another specimen

of temnodontosaurus

that is proof positive that

it really was a hunter.

Here is its stomach and inside its stomach,

you can see these tiny

little circular bones,

which are the backbones, the

vertebrae, of a baby ichthyosaur.

So we now know that temnodontosaurus

could devour young ichthyosaurs,

but would one have been capable

of eating an adult ichthyosaur like ours?

Fossils of temnodontosaurus have

been found in other regions,

including our own Jurassic Coast.

So, this monster could

well be our prime suspect.

To build our case further,

we're going to analyse another

specimen of the same species

that was found on the Jurassic Coast.

This is the skull of a temnodontosaurus

and as you can see, it's huge.

This specimen was found by Mary Anning

on the Dorset coast in the 19th century

and we are hoping that

we may be able to use it

with the latest techniques

to tell us just how powerful

these great jaws could be.

So, for the first time ever,

our team of scientists

are going to attempt to calculate

the bite strength of a temnodontosaurus.

The first step is to scan the skull.

Not as easy as it sounds.

Very few scanners are big enough,

but there's one here at the

Royal Veterinary College,

where they're more accustomed

to scanning horses.

The temnodontosaurus skull is 2m

long and weighs more than 200kg.

Luckily, it's in two pieces.

Otherwise it couldn't be fitted

into even this huge scanner.

OK. One, two, three and up.

These scans will help the team

to not only reconstruct the

temnodontosaurus' skull,

but also work out the

size of its jaw muscles.

They can then assess the power

of this huge predator's bite

and see if it was strong enough

to kill our ichthyosaur.

Temnodontosaurs are unusual

in that they had huge, sharp

teeth for cutting through flesh,

but how did other ichthyosaurs

catch their prey?

To get a clue, I've come to see a

modern day predator in action.

That is a gharial crocodile from Indonesia.

Its jaws, as you can see,

are not wide and flat

like an African crocodile's,

but long and thin and

because of that shape,

there's very little resistance to the water

so they can snatch fish, which

they do very effectively.

They're very formidable animals indeed.

Ichthyosaurs must have fed in

much the same way as that.

Their jaws were very similar

to those of the gharial...

simple studs to grip the

prey, no need to chew it

because the jaws at the

back were quite big enough

to enable the animal to

swallow their prey whole,

just as the gharial does.

Gharials regularly shed their teeth

and here's one I've just

picked out of this pool.

You can see that they're very simple

teeth, just like ichthyosaur teeth.

But that's all you need if all you

have to do is to grab a fish.

So, it's likely that our ichthyosaur

had teeth and jaws specially adapted

to catch small, slippery fish and squid,

just like a gharial crocodile.

Back in Lyme Regis, the work on the

bones has taken a dramatic turn.

Chris has found that

there is fossilized skin

over nearly the whole skeleton.

It seems to be virtually

covering the whole thing.

It's rare to find any sign

whatever of skin on fossils,

let alone so much of it.

Fiann Smithwick, an expert

on fossilized skin,

has come to take a sample back to his lab.

We can look and see if there's any evidence

of the original pigment

preserved in the skin.

- Oh, that's a lovely piece.

- That's really good. That'll be perfect.

Fiann hopes that this

remarkably preserved sample

might tell us what the skin looked

like and even what colour it was.

At the University of Bristol,

he places a tiny sample of the

fossilized skin in a machine

that coats its surface with

minute particles of gold.

They will reflect the rays of a

scanning electron microscope.

It's astonishing that you can actually see

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