All do we have left today from mighty dinosaurs are their fossils.
Stone copies of long dead bones.
It is easy to forget that these were once living animals.
Surviving in a world of unimaginable violence.
But if you know what you are looking for the signs and scars of life are clear.
As in this remarkable Allosaurus skeleton in Wyoming nicknamed... Big Al.
By studying his bones, comparing 'em with other fossils and modern animals
there is just enough evidence to raise the ghost of Big Al
from its 145 million year old grave.
Bit by bit a story of how he might have lived, can be pieced together.
It's a story that started like all dinosaurs... with an egg.
Buried in a pile of jurassic sand is a clutch of eggs.
It is the end of the dry season and there are signs of life.
This tiny little dinosaur
is facing the first of life's challenges - escaping his egg chamber.
He calls out for help.
A huge Carnivorous Allosaurus hears
the squeak of hatchlings and approaches the nest.
They are at her mercy... fortunately
this is their mother.
Smell is important to Allosaurus and from the moment mother
and hatchling smell each other.
They form a bond that is crucial for the hatchling's early survival.
Gently she uses her huge claws to free them.
This is Big Al's first day.
For now he can rely on his mother's protection
but within weeks he will have to learn to stand on his own two feet.
In seven short years he could become a gigantic predator like his mother.
But the odds on him surviving that long are low.
Al has been born into a world dominated by giants.
For a carnivore no meal comes easy here.
Some prey like the 30 ton Apatosaurus are giant fortresses of flesh
too large to attack even by fully grown Allosaurus.
Many smaller species rely on lightning fast speed
while others, like Stegosaurus, stand and fight with lethal spines.
It is a daunting prospect for this brood of tiny killers.
They will have to learn very fast
and fighting among themselves is a good way to start.
However, at this size they are just as
likely to be the hunted as the hunters.
A pair of predatory Ornitholestes watch the brood, waiting for their chance.
The mother Allosaurus is 50 times their weight
so they will not venture too while she is present.
However, the smell of all these new hatchlings will soon attract other larger predators.
So eventually the mother decides it is time to lead her unruly brood away.
Al's new home is a vast floodplain which will one day become
the badlands of Wyoming. But for now it is covered in lush conifer forest.
Dinosaurs share this world with a host of other animals
including amphibians and insects.
It is the insects that the infant
Allosaurus are after.
Born with sharp little teeth, Al is ready for his first meal.
But even small prey require skill to catch.
They are either liable to fly away or worst still... stand and fight.
The hatchlings all have a lot to learn.
That evening the mother abandons her brood while she hunts for food for herself.
She is not the only one on the prowl tonight the hatchlings are being watched by another predator.
Mother returns to her station having lost one hatchling.
The victim was not Al but ironically
the attacker is a year old Allosaurus.
These youngsters only have a few weeks
of protection before the mothers maternal instincts wears off.
And she too will view them as fast food.
Al now hunts alone.
Measuring almost 3 meters insects are no longer on the menu.
He is looking for dinosaur flesh.
There is a wide choice in this conifer and cycad forest.
A flock of small Othnielia look ideal but there's a big problem.
A heavily armoured Stegosaurus is working its way through a cycad stand nearby.
The Othnielia feed of the smashed cycads he leaves behind.
This means they are sticking very close to him.
Too close for a small predator to get in between and attack.
A mother Ornitholestes attending her nestmand may prove more promising.
But a small Allosaurus is about to find out he is no match for an overprotected mother.
Nearby a group of Dryosaurus offers Al one more chance.
Al cannot possibly run down such swift prey.
He needs to learn to ambush.
He has also ended up too nearly edge of the forest.
A herd of Apatosaurus are crushing through the outer forest looking for new plantwork.
Not exactly suitable prey for Al.
Back among the trees, Al finally finds something to take the edge of his hunger.
A nearby stagnant pool offers plenty of opportunity to scavenge meat
as many dinosaurs have come here to drink and become stuck in its thick mud.
A recent victim is this Stegosaurus, that lies where it died of exhaustion trying to drag itself free.
But dead bodies also attract adult Allosaurus.
This one is large enough to kill Al.
But she would prefer a free meal.
Unfortunately the churned up swamp left by the Stegosaurus is dangerous.
And one of her kind is already become chunked next to the carcass.
Ignoring the danger signals the new Allosaurus approaches the carcass to feed.
By the time she realizes she is trapped
it is too late.
Al watches from nearby only escaping the same fate
because he has learned to avoid carry and the large carnivores that it usually attracts.
By evening two more carcasses lie beside the pond.
This swamp is a natural predator trap
and before the Stegosaurus finally rots away
numerous more carnivores could fall for its attractions.
The bodies are left to those that can feast here in safety, the flying Terrasaurus.
In the middle of Al's jurassic world is a
vast salt lake. Its crystalline white crust formed by the retreat of an ancient sea
occasionally it shores see the movement of herds of dinosaurs.
These are Diplodocus heading for a nesting site to the south.
It is a grim journey for this mighty creatures
and the heat and lack of drinking water
weeds out the weaker animals. Predators know this.
Predators like Al.
Is now 5 years old and although he is 9 meters long
is not yet fully grown.
Al is an experienced hunter
but the herd itself presents a formidable barrier to predators.
Still, Al is not the only predator stalking the herd.
They can all smell that one of the Diplodocus is in a very bad way.
The predators are getting impatient
they need to break the herd and isolate the weakling.
The panicked herd has left the sick Diplodocus far behind.
The Allosaurus gather for the feast.
However, even the sick and exhausted Diplodocus is a fearsome adversary.
Built for speed, Al is frequently wounded in such situations
but he cannot afford to let this slow him down.
The competition is too intense.
The other carnivores hold back and wait for time
and the heat to finish the giant herbivore.
After several hours, heat exhaustion and his illness bring the Diplodocus to his knees.
The predators finally get their reward.
Although there is enough meat here for weeks there is an urgency in their feeding.
The smell of blood will soon bring others and every Allosaurus wants to eat its fill.
Within the hour a gigantic
female Allosaurus appears out of the haze.
She is about twice the weight of the other Allosaurus and
4 meters longer. Quickly she establishes her dominance.
When predators get to her size they rarely have to bring down their own food.
They just scavenge other kills.
Al tries to find a safer place to eat.
The flood plains where Al lives are ruled by the seasons.
Short periods of heavy rain give way to long months of drought.
It is now the end of the wet season and with the flood water still receding
it is a time of plenty for the local dinosaurs.
For many it is also a time for mating.
This pair of Stegosaurus are about to try what is for them a very complex process.
Al is now 6 years old
and as the sign of age, the crests over his eyes are now reddening.
Sexual maturity is dependent on his size and at 10 meters long,
Al is well on the way to being big enough.
He is however making the locals at the waterhole nervous
and the smell of blood he brings with him is enough to interrupt the amorous Stegosaurus.
Away from the lake, Al picks up a new scent.
Dung left by a female Allosaurus has an immediate effect on Al
and for the first time in his life, he issues a mating call.
The female is not far and picks up the low sounds in his call.
She is much larger than Al. He will have to be careful.
She is not interested, but Al's inexperience shows
and he gets... too close.
Al is lucky. Although he had a torn arm, ripped claw
and smashed ribs, he has escaped having his throat torn out.
After five months, the dry season begins to bite.
The sick and the old are being weeded out.
This is good news for scavengers.
This carcass is dried hard and the Pterosaur burrows deeper to find softer meat.
But it is never safe to become too preoccupied.
Al has managed to recover from his fight,
although one arm is still not functioning properly.
The Pterosaur was not much of a meal and there is little left on the carcass.
He needs fresh meat.
In the blistering heat, he starts to stalk a flock of swift Dryosaurus.
It will take skill,
but he has done this hundreds of times before.
The attack is a disaster.
Al has fallen badly.
As he tries to get up, it's clear he has broken something in his right foot.
With prey getting scarcer and scarcer, his chances of survival now look remote.
Two months later and the draught has continued longer than usual.
It has cost Al dear. If anything, his limp has got worse.
Because of his poor condition, his body is not healing well.
It appears he broke his middle toe in the fall and it is now badly infected.
Too weak to hunt, he'll be lucky to survive much longer.
The drought drags on.
A pair of young Allosaurus are out hunting for insects amongst the sand dunes.
Instead, they find something much larger.
The emaciated body of big Al.
Al never reached his full size. Instead he died as a mature adolescent in a dried up riverbed.
Eventually, the rains would arrive
and gently bury his body in silt for a 145 million years.
The process preserved his skeleton perfectly.
Including the lumps where his ribs healed after their break.
The raging infection on his middle toe and at least
70 other injuries and diseases.
In death, Big Al represents a frozen moment
in the fast and furious life of a carnivorous dinosaur.