All language subtitles for Big.Al.Uncovered

The Ballad of Big Al

was a huge technical challenge,

taking over a year to make.

But this was nothing compared
to the enormous amount

of scientific research that inspired the film.

This is the story of how so much is known

about one very dead dinosaur.

Scientists are uncovering the remains

of an allosaurus, a dinosaur that roamed.

The excavating team hopes to have Big Al

out of the ground by week's end.

You have to very carefully chip away the rock,

try to put together the whole story of this animal.

In 1991 out of the rock

came a paleontological star,

one of the most complete
dinosaur skeletons ever found.

He was nicknamed Big Al.

And here we have what a claw from allosaurus

would look like, so again, it's like.

After 145 million years,

Al's back on his feet again

at the University of Wyoming Geological Museum.

But scientists have been able to do more than

just rebuild his body.

After extensive forensic analysis of his bones,

research into other fossils,

and the behavior of his modern relatives,

they know more about Big Al
than almost any other dinosaur.

It all adds up to a great
paleontological detective story.

Like all good thrillers, the first clues

had to be gathered at the scene of the crime.

This is a site in Wyoming where Big Al

was discovered in 1991.

And Big Al died 145 million years ago

during the late Jurassic period,

and was buried in a river channel deposit

that's now part of the Morrison Formation.

Things would have looked a
lot different at that time.

It would have been much flatter.

We wouldn't have had any flowering plants,

and in their place we would have had ferns,

cycads, even conifers.

At that time, Wyoming was full of dinosaurs.

Most were the lumbering
plant-eaters like diplodocus

and the armored stegosaurus.

Far less common were the carnivores,

but this hasn't stopped them becoming infamous,

like the allosaurus.

These fearsome predators were the T.
Rex of their day,

and Al was one of them.

But like every living thing,

these monsters started off small and delicate.

Despite this, science can still tell us something

about how Al probably started life.

We're very familiar with how
life begins for humans,

but you might be surprised to learn how

a Jurassic carnivore raises its baby.

Evidence for this comes from remarkable fossils

found on the Atlantic coast of Portugal.

It was in this place that we found, in 1993,

a small eggshell like this,

that we figured out it was from a dinosaur.

In further years we've dug it and we found

more than 100 eggs,

that makes one of the biggest nests in the world.

But more significantly, they found something

which could tell them who these eggs belonged to,

the most rare and sought-after fossils of all,

tiny preserved bones of baby dinosaurs,

still curled up inside their shell.

We have found more than 200 embryonic bones.

With them we can see exactly
which kind of dinosaur we have.

In this case, it's a meat-eater
dinosaur, a carnivore,

and we have almost all skeleton here.

And if there were eggs,

there must have been a nest.

Bizarrely there is information about this

in the fossilized eggshells themselves.

Under the microscope, scientists can identify

holes in the shell.

Their large size allows maximum air

for the embryo to breathe,

which tells them that these eggs were buried,

packed together in an underground nest.

Scientists know this because there are animals

alive today that do the same thing, the crocodiles.

This is not surprising, because crocodiles

and alligators are one of the dinosaurs'

closest living relatives,

and with scaly skin and a mouth full of teeth,

it's easy to see the family resemblance.

But carnivorous dinosaurs have an even closer

group of relatives who share
some of their other traits.

They are the birds.

Standing on two legs, Big
Al's skeleton was actually

more like a bird than a crocodile,

but in practice he was a strange mix of the two.

So after Al hatched, did he
feed himself like a crocodile,

or wait to be fed, like most birds?

Evidence found at the site
in Portugal provided a clue.

Inside the eggs we have found several teeth

that are quite rare,

and in these teeth we can tell a lot of things,

for instance, they're born with teeth.

Since they were born they were able to chew

and to eat soft meat, for instance.

Being born with teeth

would have made all the difference.

Although they were too small to tear up chunks

off his mother's dinner plate,

they were probably perfect for capturing insects.

Just like baby crocodiles,

it seems Al was able to fend
for himself from an early age.

But Al's biggest problem at this stage in his life

was being eaten by a bigger dinosaur.

His only defense was to grow up fast.

And an amazing collection of allosaurus bones

shows just how quickly a baby dinosaur could grow.

What we have here are allosaurus thigh bones,

and what's unique is the fact that they're going

from very, very small to very, very large.

And if we take this smallest bone here,

we can see that it's about
18 centimeters in length,

and it would probably belong to a dinosaur

that was maybe a meter and a half in length

and possibly stood off the ground

about a meter or so.

If we look at this larger bone over here,

this sub-adult, we probably will have an animal

close to eight meters in length,

this bone itself being about a meter in length.

And it probably stood off the
ground about 2 1/2 meters.

As we look at allosaurus' bone,

we can make thin sections of it,

and then we can compare it
to crocodiles and to birds.

As we compare it to birds we see that there is

so much similarity that we know that allosaurus

probably grew very rapidly like a bird would.

So Al was born like a crocodile

but grew like a bird,

probably reaching full size
in just six to eight years.

And by the time a child is just starting school,

Al would have already been
a fine physical specimen.

Hey, pass it to me, I'm up ahead, please!

It's the last time I play with a dinosaur.

Dinosaurs.

So how did he feed this fantastic growth?

Again, his two living relatives may provide a clue,

but they have very different approaches to eating.

Their strategy in feeding is plenty of time.

That's all they've got, is a lot of time to wait

for something to make a mistake,

a person or another animal.

It's bite first and then ask questions later,

that's what they do.

They grab something when it
offers the opportunity for it,

such as my leg right now.

Let me move this animal, she's
gonna be real testy here.

This is a little female, move girl.

Thank you.

Oh, now here's a great opportunity to see

the basic difference between
a bird and an alligator.

What we see is how a bird is choosing to feed.

The great part is, is anytime you see

a bird like this feeding, is it can actually take

and pick out its food amongst the twigs and sticks

and other pebbles and things here.

It selectively picks them up and swallows them.

An alligator on the other hand

will strike at anything it sees.

What we're gonna try to do here

is trick these alligators into coming after

the dinosaur down here.

See they don't really care
what it is they're grabbing.

They're opportunic eaters,

they see something they perceive as a food item,

and they go for it.

The alligators use their excellent

sense of smell to track down their prey,

and dipped in fish oil,

even the inedible toy seems tempting.

In fact, the differences between the bird

and the alligator's behavior is reflected

in the shape of their brain.

A look inside Al's head could provide

direct evidence of his behavior,

and although allosaurus are long dead,

a remarkable fossil has let
scientists do just that.

It's a brain, cast from the
inside of an allosaurus skull.

How does this compare with his relatives?

Well let's start with the bird.

Here's a model of a bird.

If we look at the way the bird is,

we find out that a bird has a very large region

that's dedicated to processing information,

and a very small region dedicated to sensory input

such as smelling something.

Well, what about an alligator?

If we take the alligator brain

and compare that to allosaurus,

we see something that looks very, very similar.

This is sensory information that comes in here

and then goes to a region
that's actually rather small

for processing that information.

And it snaps at it,

so it just strikes and hits whatever smells right.

That compares extremely well with allosaurus.

Therefore these features tell us that if we want

to compare allosaurus to a modern-day animal,

that would be an alligator,

because their brains resemble
each other very, very much.

Consequently their behaviors
must have been very similar.

There is an extraordinary and baffling site

in Utah that might just bear witness to this sort

of feeding behavior.

Cleveland Lloyd dinosaur quarry.

Over 10,000 dinosaur bones have been found

jumbled together at this one site.

But as the different bones were identified,

something strange emerged.

They found hundreds and
hundreds of allosaurus bones

and just a few of the plant-eating dinosaurs,

the total opposite of what you would expect.

It was a mystery why the predators
outnumbered their prey.

What might have happened here is the fact

that we have a bog area that
collects small pools of water

that would attract stegosaurus
and some other animals

that would be prey for the allosaurus,

and they would get stuck in the mud

and might be there for days.

They might stink, they might be very attractive

to an allosaurus that would
be glad to jump in there,

not realizing that they would
become entombed themselves,

just like their prey.

The allosaurus were probably

led to their death by their noses.

They couldn't ignore the stinking
attraction of a carcass.

What probably happened is,

when the dinosaurs got into the bog

there was a lot of dinosaur bio-turbation,

or a lot of dinosaurs mixing up a lot of the mud,

hence we have a huge, huge column of bones

that goes quite deep, and they're all mixed up.

The remains of at least 44 allosaurus

were found at this one site.

It looks like this was a natural predator trap.

So Al's brain was probably
something like an alligator's.

They lie in wait for a meal to come to them,

but Al's body was built differently.

He looked more like a bird,

and they don't hang around for food to wander by.

Just like the brain, these two different lifestyles

leave their mark not only on the skeleton

but on the body's internal organs.

Ostrich tend to be able to run great distances

and keep speed and activity up all day long,

and they have to do that so that
they can gather their food.

To help them do that they
have a heart that delivers

oxygen very efficiently to
all the tissues of the body

after it's gone through the lungs.

Crocodiles on the other hand really sit and sneak

and kind of wait for prey to come up to them.

They can move very quickly for a short time

but their heart and the way their blood works

and their tissues work don't allow them

to sustain energy for a long period of time.

Nowadays to find out how a heart works,

medicine has invented machines for scientists

to see inside the body.

At the North Carolina College
of Veterinary Medicine,

an alligator is due for a CT scan.

To prevent him injuring himself or the team

his eyes are taped over and
his arms and legs restrained.

This is an alligator straight jacket.

That'll be good.

To help relax the alligator,

a bizarre form of hypnosis is used.

We're just putting him to
sleep by stroking his belly

and it helps an awful lot
that he has all the tape on,

so we can get to his belly.

But this actually works.

Go to sleep.

Nothing happened.

Okay Paul, turn the lights out
so we can see the guidelines

and let's get him set up and start there.

The images on the screen show

a cross-section through the alligator's chest,

and with each new scan they are building up

a picture of the structure of the heart.

However until recently there was little point

in doing this to a fossil,

because soft tissues don't normally fossilize.

With skeletons like Big Al, scientists could only

speculate on what was inside the dinosaur's chest.

But this year a highly controversial find

may have changed all that.

This is an absolutely superb specimen

of a small plant-eating dinosaur.

We call it thescelosaurus in paleontology,

but here at the museum we like to call it Willow,

the little dinosaur with a heart.

And in this region is the actual
preservation of structures

which demonstrate the presence of a heart.

This structure was so peculiar that my colleagues

decided to probe it with an x-ray scan.

To help read Willow's scan,

the images inside the alligator's chest

provide a guide.

As we move through the thorax,

we're gonna see the lung fields,

and then coming up between the two lung fields

we'll start to see a solid
mass, and that's the heart.

Shown on the alligator scan as a graphic,

the two aortas, or tubes which
carry blood around the body,

are highlighted.

They lead from the two ventricles of the heart.

This plumbing, although perfect for an alligator,

only allows it short bursts of activity.

Inside Willow the picture appears to be different.

If you look at this
three-dimensional reconstruction

of Willow's CT scan, we can see right here

that the two ventricles are easy to identify.

Highlighted at the bottom of the picture.

Then look up above the heart base,

we see this corrugated structure,
that's the single aorta.

If this is a single aorta,

it would be remarkable, because it would show

that this dinosaur's heart had the potential

to power it for the marathon as well as the sprint,

unlike the crocodile's.

Apparently this little dinosaur had a heart

that was more like a bird or a mammal

than like a crocodile.

This intriguing fossil is still under scrutiny

but if confirmed, Willow's heart will give a new,

more energetic look into the dinosaurs.

If this dinosaur had a heart that looks advanced,

then that implies that it also
had a high metabolic rate,

and now instead, there is ample reason

to think of these as rather
high-energy, active animals.

With the body of a bird
but being 10 meters long,

Al could have run at speeds of
up to 30 kilometers per hour.

If there was any doubt whether
Al led an active life,

there is conclusive evidence
written in his very bones.

Rebecca Hanna knows Big Al better than anyone.

She's spent much of the last eight years

examining every inch of his skeleton,

and her search has revealed that he had

over 19 abnormal or injured bones in his body.

It seems that this is an unusually high number

for an allosaur to have, in comparison to other

allosaurs that I've looked at.

Now what this may mean or suggest

is that Big Al may have been more aggressive

than other allosaurs,

or he actually may have been just sort of clumsy.

Clumsy or brave, Al's bones reveal a chronology

a chronology of accidents in
the latter years of his life

that made him famous as the dinosaur

who lived fast and died young.

Big Al received an injury
to this section of his tail

probably one to two years before he died

and the way we can tell that is the amount

of re-healing on the bone.

This bone was broken in half
and then healed back together,

so there is a little bit of a bulge there where

you can see where it was broken
and healed back together.

But for the most part,

it's looking more like the original bone.

It looks like Al took a nasty knock.

But it obviously didn't slow
him down because Rebecca Hanna

found out that he was shortly in trouble again.

When I was first studying this bone

from the right hand of Big Al,

it was unclear what had caused it to look this way.

I knew it was abnormal for some reason,

so what I decided to do was
to cut a very thin section

to look at the actual bone microstructures.

What I discovered was that this
bone was actually fractured

right along its length, called
a longitudinal fracture,

and we can see that under the microscope.

The break runs diagonally

through this cross-section.

Below it rows of normal bone
lie tightly packed together.

But above it the bone is more loosely woven,

a sure sign it's trying to mend.

The bone was broken by some sort of twisting force

and this bone was broken

after the tailbone injury event,

and we know that based on bone microstructure

and also just the look of the bone.

It didn't stop there.

Al went on to break four ribs and hurt

his backbone, shoulder, and pelvis.

Even with all these injuries, Al had to keep going.

But eventually something happened to him

that would threaten his life altogether.

It could have been just a careless trip,

but it cost him dearly and probably spelled

the beginning of the end.

Al's left foot looks normal,

but there is a huge amount of abnormal

bone growth in the right foot.

This is the most serious problem Big Al had.

It's in the right foot, the third toe.

The infection in this toe bone was very long-lived

and so it's probably not something that happened

right at the time of death.

Big Al probably would have had to have been alive

with this infection in the bone,

for at least six months to a year.

And it probably would have caused this animal

a great deal of pain and caused it to limp,

because you can imagine with
this type of inflammation

when the bone is usually about that wide,

it would have actually been rubbing against

these other two toes.

Although Al's injuries didn't

kill him instantly, they stopped him hunting

and left him struggling to find food and water.

If at this point a drought hit,

it would have been enough to tip him over the edge.

145 million years later, it
seems enough clues were left

to piece together the last few hours of Al's life.

Big Al was found, when the tailbones here

were on the edge of the hillside,

and as they excavated further into the hill,

the found more tailbones which continued on

and connected with the hips,
the rest of the backbone,

and even the skull.

So this is a decay posture that occurs

when the ligaments that run along the spine

dry out and decay, arching the head and tail

back over the legs towards each other.

What this tells us is that the animal died

and layed out for some period of time.

And we've estimated that Big Al layed out

on the surface for a period of a couple of months.

It's possible that Big Al
came to this river channel

in search of water, and usually it had water in it

and was a drinking source for him,

but at this point in his life it was dry,

he was afraid to leave it,

maybe he was so injured he couldn't go

great distances for water,

and was hoping that eventually
water would flow down here.

And he may have actually died of thirst.

When water finally came,

it was too late for Al, but ironically,

the flood sediments that gently buried him

ensured that his bones were beautifully preserved,

so that 145 million years later,

no one would forget him.

♫ Oh, how I loved ya

♫ Since the day you first told me your name

♫ Yes, I have loved you

♫ Thinkin' you all the while felt the same ♫