Deadliest Planet Dinosaur Files

If you thought you knew

all there was to know about dinosaurs, think again.

I'm Jem Stansfield and this is Planet Dinosaur Files,

the series that rewrites the prehistory books.

We're bringing to life the most awesome beasts to walk the Earth,

with state-of-the-art CGI technology that makes you feel

like you're right there.

And I'll be discovering

what made these massive, lethal and, frankly, bizarre beasts tick.

I'll be devising demos with a real cutting edge.

Sparks will fly and I'll even be using genuine shark teeth.

In the last 20 years, scientists have discovered more dinosaurs

than in all the centuries that have gone before.

Amazing new discoveries.

They reveal a jaw-dropping cast list of creatures.

Bigger...

..weirder...

deadlier than we'd ever imagined.

And this time on Planet Dinosaur Files,

we're asking the question, "Which of these creatures was the deadliest?"

You might think you know about dinosaurs.

Like the huge, 12-tonne plant eater Diplodocus.

Or the mighty Tyrannosaurus rex, a savage predator

who dominated half the planet for almost five million years.

Well, think again.

Prepare to meet the new deadly dinos on the block.

Troodon, a cunning hunter,

big-eyed and brainy, whose speciality was the night attack.

Mapusaurus, a bloodthirsty meat eater with lethal gnashers.

A predator that could take on

the biggest creature that's walked the Earth.

And Spinosaurus, an incredible, massive monster...

..who could hunt prey in both water and on land.

An amazing all-round killing machine.

Three of the most lethal,

versatile hunters to have ever roamed the planet.

I'm going to look at just what makes these dinosaurs so deadly.

First up, how deadly are their teeth?

A great set of gnashers are a must for a top predator.

Next, weapons.

What do they have in their armoury that can help them get a meal?

This could be anything from a superb set of claws to amazing eyesight.

And, finally, hunting skills.

Do these deadly dinosaurs hunt alone or in a pack?

When do they hunt and what can they hunt?

Let's meet our first contender.

This is Troodon.

We thought we knew all about this dinosaur,

but a recent discovery has shown we've plenty to learn

about this deadly fella.

Troodons lived in North America 70 million years ago.

Only two metres long, they'd be up to waist height on an average human.

Don't sound too threatening, do they?

Well, the fossils of a new Troodon found in Alaska,

in the United States, show this was a creature way more menacing.

But how can we be sure? By studying the evidence - that's how.

Look at these two Troodon teeth.

One is twice the size of the other.

It's one of many found in Alaska in the frozen north of the USA.

In 2008, a study of these teeth

revealed a new kind of super-sized Troodon.

The average Troodon was usually about the size of a Great Dane dog.

But those whopping Alaskan Troodon gnashers

show this was a predator loads more deadly than we imagined.

Alaskan Troodons were four metres long -

twice as big as other Troodons.

These Super Troodons were much heftier,

but were still pretty small

alongside this huge duck-billed Edmontosaurus

that they hope will provide their next meal.

Edmontosaurs could be 12 metres in length -

that's as long as three rhinos standing in a line.

So, you wouldn't think that the herd would be in any real danger

from the Troodons. Well, size isn't everything.

At sunset, the odds switch in the Troodons' favour.

In a place as far north as Alaska,

it can stay dark at night for a whopping 18 hours.

The Edmontosaurs might be asleep, but these Troodons aren't.

And these are clever creatures, as well.

Of all the dinosaurs we've discovered,

they have the biggest brains compared to their body size.

And, what's more, they have very, very good eyesight.

There are plenty of meat-eating animals in the wild today

that specialize in night hunting.

This jaguar lives in the jungles of South America.

These pecarries, a kind of wild pig, are the prey it's going after.

The big cat's superb night vision gives it a crucial advantage.

It can see its prey.

But the peccary can't see the jaguar,

giving the big cat the chance to pounce.

Now, a Troodon's eyes are so good in the dark

because they're very large, and also they face forwards -

a great advantage for a predator,

because with two eyes focusing on one target in front,

Troodons get a better sense of depth and distance,

helping them to hunt prey.

The Edmontosaur's eyes, though,

are smaller and so once the sun goes down, its advantage Troodon.

As the Troodons go among the herd, they quickly cause panic.

What they're looking for is a vulnerable, smaller youngster,

separated from the adults.

This kind of behaviour is exactly what you find in the wild today.

Here, a pride of lions are hunting at night

amongst a herd of elephants.

They're filmed using infrared photography,

so we can see them in the dark.

Now, lions don't often attack elephants because they're so big.

But at night the lions' much-better eyesight

increases their chances of a kill.

Like Troodon, they choose their target carefully.

This elephant, smaller than the big adults,

is on its own and vulnerable.

Just the opportunity the lions are looking for.

The Troodons have also found their prey -

this young Edmontosaurus has separated from the herd,

and the Troodons grab their chance.

Time for their teeth to come into play.

But just how deadly were those Troodon teeth?

Welcome to the Planet Dinosaur Files workshop.

For a dinosaur to be deadly, it obviously needs sharp teeth.

Different teeth do different jobs depending on the type of prey

and how it catches them.

But just how deadly are a set of dinosaur gnashers?

Well, here, I've got three teeth that are almost identical

to those of the Troodon. They're from an oceanic white-tipped shark

but, in style and size, they are practically the same thing.

Now, things to notice with these teeth -

very pointed, curved, but, most importantly,

they've got these tiny serrations along the edges.

Now, these operate a little bit like my most effective kitchen knife.

What these serrations do is when the animal bites down,

effectively the full force of its jaw

is concentrated on each tiny point.

But to really get a feel of how good these teeth are,

we've made our own fake dinosaur flesh.

We've used a tough latex rubber to provide a fair bit of resistance

and, hopefully, give us an idea of what it'd be like

to bite into the flank of an unfortunate herbivore.

As you can see, this dino flesh is pretty tough stuff.

Now, first thing I want to test is the piercing power of these teeth.

What I'm going to do is just give it a little bit of weight.

Whoa!

OK, so that's like a decent one-finger push.

That's all it takes to get Troodon teeth into our fake dinosaur flesh.

But, if you're a Troodon, all you've done is hurt your prey.

You haven't got dinner. For that, you've got to rip flesh out.

Oh, wow! They are astonishingly good. I thought the skin'd put up

more resistance than this. These teeth cut through that flesh

almost effortlessly. If you look, that is a hideous cut!

These are frighteningly good teeth, which is why the Troodon really was

one of the top predators in its area.

Back to the long Alaskan nights 70 million years ago.

These Troodons have got their prey right where they want it.

But they can still be caught unawares.

A big parent Edmontosaurus

has come to the rescue of this youngster in the nick of time.

These Troodons will have to look somewhere else for tonight's dinner.

So, that's Troodon, then.

It had small teeth but, with those serrations, they were razor sharp.

Weapons? Well, it had brilliant eyesight

that it used to increase its chances of a kill.

And its special hunting skill was the night attack.

But to be really lethal in the dinosaur world,

you need the ability to take on virtually anything. Time to...

ratchet up the deadly factor.

This is Mapusaurus -

a terrifying killer.

It lived 25 million years before Troodon was around.

That's 95 million years ago. Its territory was South America,

roughly where you'd find Argentina today.

This Mapusaurus is hunting amongst a herd of Argentinosaurs -

a big challenge, because these herbivores

are one of the largest dinosaurs known to have walked the planet.

True, a Mapusaurus is much bigger than a Troodon,

measuring ten metres long and weighing in at four tonnes -

nearly the size of a T-rex.

But how could it possibly take on a gigantic 75-tonne Argentinosaurus,

an incredibly powerful dinosaur

that weighed the same as five double-decker buses?

By working in gangs - that's how. Let's take a look at the evidence.

In Argentina in 2006, an amazing discovery was made.

The fossil skeletons of seven different Mapusaurs were found.

What's more, they were all together.

One Mapusaurus on its own

would be no match for a fully grown Argentinosaurus.

What this fossil find could mean

is that these carnivores hunted as a group.

In the wild today, there are lots of predators

who work together in gangs, as well.

In southern Africa,

this pack of wild dogs show how important team work is.

They're hunting impala, a type of antelope.

Some of the dogs chase,

while others peel away, trying to cut off the impala's escape route.

But this time the impala takes desperate action,

by running into a river to get away from the pack.

95 million years ago,

gangs of Mapusaurs were working as teams, as well.

This lot are circling a group of Argentinosaurs,

looking for a victim to attack.

And these meat eaters have some of the most lethal, deadly teeth

of any dinosaur that's lived.

Razor-sharp blades that can slice off chunks of flesh in a flash.

That mouth has more cutting edges in it than a set of chef's knives.

And because Mapusaurus is so quick compared to Argentinosaurus,

it can actually feed off the flesh of this massive plant eater

without having to kill it.

Pretty gruesome!

Time for the next tooth test.

This is one of my Mapusaurus teeth.

Whereas Troodon's teeth are pretty much the same as a modern-day shark,

there's now nothing on this planet that has the vicious dentistry

that used to be in the mouth of the Mapusaurus.

The significant features of the Mapusaurus teeth are its size.

I mean, these are huge teeth! Again, very sharply pointed and curved,

but also, they have a vicious edge on them.

Now, Troodon's teeth made short work of the dino flesh.

How will Mapusaurus's gnashers compare?

What we really want to find out is how good the teeth are.

I'll start pushing them in.

Now, they take a bit more effort -

quite a lot more effort, they're bigger teeth.

It's important to remember Mapusaurus was a massive animal.

It was considerably more powerful than me. But I WILL get these in.

I'm just about in there now.

Let's see what it's like for ripping through the flesh.

You wouldn't want to be on the sharp end of that.

It's a messy business if you get bitten by a Mapusaurus.

Now, I can see with this why the Mapusaurus was so massively feared,

because it had the power to sink those huge teeth

into the flesh of its prey, and has the strength in its body and neck

to then pull them through.

This is going to take huge chunks of flesh off an animal,

which is why the Mapusaurus was able to attempt

to take on something massive like the Argentinosaurus.

That's Mapusaurus, then.

Its teeth ripped through flesh.

Absolutely lethal.

For weapons, it had both speed and power.

And hunting skills?

Well, this was a fearless killer that hunted in gangs.

But don't forget - Troodon's brainier and has better eyesight.

One thing's for sure - both these dinosaurs are fantastic hunters,

with the weaponry to be a top predator.

But remember - I'm trying to find the ultimate,

stand-out prehistoric killing machine.

And this next awesome monster could be my leading contender.

Spinosaurus!

It looks like no other beast I've ever seen.

In the dinosaur world, this is the Terminator.

At a stunning 17 metres in length and 12 tonnes in weight,

Spinosaurus is one of the largest predators

to have ever walked the planet.

If T-rex had been around at the same time,

it would have needed a ladder just to look Spinosaurus in the face.

But this huge hunter, four metres longer than mighty T Rex,

roamed the planet 30 million years earlier.

It ruled the roost in North Africa.

Back then, this was a land of desert, but also rivers and swamps,

where plant eaters like these Ouranosaurs lived, as well.

Those massive two-metre-long spines on its back

give this dinosaur its name. Spinosaurus means "spiny lizard".

But luckily for these herbivores,

they're not usually on the menu for Spinosaurus.

This predator's favourite prey lived elsewhere.

Spinosaurus' meal of choice was fish, not meat.

This is a dinosaur that loved to hunt in water.

Standing in the river shallows, Spinosaurus plays a waiting game.

It's on the lookout for one of these -

Onchopristis, a giant eight-metre-long sawfish.

There's enough fresh sushi there for a whole Japanese restaurant!

This Grizzly bear hunting in a river in Canada

loves a bit of raw fish, too.

He and his mates know that thousands of juicy salmon are swimming

up river - and they're waiting for a meal to come their way.

And their super-quick reactions mean they can catch this fish in mid-air.

But how do we know Spinosaurus was as partial to fish as that bear?

By looking at the evidence - that's how.

These are the tooth sockets in a Spinosaurus's jaw.

It was found in 2005 in North Africa.

Stuck in one of the sockets is a tiny piece of backbone

from another creature.

This Spino clearly didn't brush his teeth before he went to bed!

That bone fragment was from a sawfish, possibly Onchopristis.

These juicy fish were one of Spinosaurus' favourite foods.

And, a bit like a bored angler, Spino would spend hours

waiting for these tasty river treats to swim by.

Here was a beast that loved poking its snout into a fast-flowing river.

And Spinosaurus's way of catching fish is really clever.

Its secret lies in that snout.

It has lots of small holes in it

that are very similar to those of a crocodile.

In a crocodile, these snout holes contain special sensors.

These help the croc to feel small changes of pressure,

caused by other creatures disturbing the water nearby.

That signal is one of the ways it zeroes in on prey.

And there are other creatures that have hunting sensors.

Take sharks - they have a kind of electrical sensor in their snout,

which helps them detect the movement of other fish in the water

without having to see them.

Dinosaur experts believe the Spinosaurus

had sensors like the crocodile -

an amazing ability that meant it could strike at these Onchopristis

without even seeing them.

And its long teeth, shaped like a cone with a very sharp point,

were perfect for gripping these big, slippery sawfish.

Time for our final tooth test.

This is one of my Spinosaurus teeth. I've built them

to closely resemble ones that have recently been dug up.

They're quite distinctive.

They're essentially a long, pointed cone

but they've also got this slight hook on them.

Troodon's teeth cut effortlessly through my dino flesh.

Mapusaurus took longer to pierce but once in,

it made a horrible mess.

So, how will Spino's gnashers get on?

Let's see how they go on the piercing test.

That borders on being shockingly easy!

As I experienced with the Mapusaurus,

this is pretty tough stuff.

The design of these teeth is obviously very effective.

Now, how does it do for ripping and tearing?

I think the easy answer is, it just doesn't!

There is no way that those teeth are tearing through that.

But that is for a reason.

Because when a Spinosaurus locks into its prey,

it wants to make sure that prey is unable to rip itself out.

That's the point of the Spinosaurus. Its teeth aren't there for ripping -

it hasn't got the serrations, like the Troodon,

or the razor-sharp edges, like the Mapusaurus.

It just wants to hold stuff.

When you're grabbing slippery, wriggly fish,

that's a very effective weapon.

But, actually, that's not the whole story with Spinosaurus -

because this killer had another lethal weapon to deal with prey.

As soon as Spinosaurus releases its catch

from its long, gripping teeth, just watch as those powerful arms

and vicious claws do the job of tearing flesh.

And there's another factor in Spino's favour.

It was massively adaptable.

This was a dinosaur that was deadly just about everywhere.

As well as swimming and hunting in water,

it could face down fearsome opponents on land -

like this big predator, Carcharodontosaurus.

And it could even feed on creatures of the air,

like this pterosaur - a flying reptile.

We know Spinosaurus fed off pterosaurs because its teeth

have been found stuck in a backbone of one of these winged reptiles.

This really was a killer capable of taking any prey it liked.

Well, that's Spinosaurus - a massive super-predator.

So, how does this awesome killer

compare with our other deadly dinosaurs?

There was Troodon - small, but cunning and vicious.

On the teeth test, it was razor sharp.

For weapons to catch prey, it had a clever brain and superb eyesight.

And its special hunting skill was the night attack.

Then the mighty Mapusaurus.

A terrifying killer that took on the biggest dinosaur on the planet.

For the teeth test, it was absolutely lethal.

Weapons in its locker? Well, there was speed and power -

and some very handy hunting skills when it attacked in gangs.

And, finally, Spinosaurus, the Terminator of the prehistoric world.

An astonishing all-round killing machine.

Spino's teeth were terrific at piercing and gripping.

Its range of weaponry - savage claws, amazing snout sensors

and sheer brute strength in a fight - was stunning.

And fantastic hunting skills.

It could take on huge fish or big meaty dinosaurs,

and easily switch from rivers to land.

Spinosaurus has to be my ultimate deadly dinosaur. And by a long way.

Next time on Planet Dinosaur Files,

I'll look at some of the most powerful predators

in the prehistoric world.

And in the Dino Workshop, it's crunch time!