Planet Dinosaur (2011): Season 1, Episode 2 - Feathered Dragons - full transcript

We're 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.

With the most extraordinary
fossils...

from dinosaur embryos to
the exquisitely preserved.

And using the latest imaging
technology,

cutting-edge research
has allowed us to probe deeper



and reveal more than ever before.

It gives us our first truly global
view of these incredible animals.

In this episode
we look at the new, bizarre

and extraordinary feathered
dinosaurs,

many of which have only just
been discovered.

Some conquered new worlds.

Others grew to gigantic sizes.

As we learn more about the evolution
of these feathered beasts,

they're revolutionising
our understanding of life on Earth,

blurring the boundaries
between dinosaurs and birds.

For over a century,
the great dinosaur discoveries

came from North America and Europe,

but in the last decade or so,
the focus shifted.

One country now sits at the centre
of the new dinosaur revolution...



China.

In recent years, spectacular fossils
have been uncovered here.

Amazingly preserved, these fossils
revealed exquisite new details.

And they are giving us incredible
glimpses into an alien world,

a world full of the most bizarre
dinosaurs we have ever seen.

Possibly the strangest of all
lived 154 million years ago,

in the late Jurassic period.

An animal that looks like
nothing else on earth.

Hiding in these lush forests
is Epidexipteryx.

The size of a pigeon, everything
about this creature is odd,

from the length of its arms
to the shape of its teeth.

This forest is home
to many predators

and being small
makes it vulnerable.

This is Sinraptor.

A small dinosaur like Epidexipteryx

would be of no interest
to a seven-metre adult.

But this is a juvenile,

and Epidexipteryx
is a perfect-sized snack.

Being small does have
its advantages,

because it can escape
to the safety of the trees.

Everything we know
about Epidexipteryx

comes from an incredible fossil,
first revealed in 2008.

It showed an animal with a small
skull and large eye sockets,

and unusually long teeth.

With toes suited
to gripping branches

and very long arms and hands,

it suggests that this was
a dinosaur well suited

to living in the trees.

The extraordinary,
elongated third finger

is another distinctive feature
of the group.

With this and its projecting
front teeth, Epidexipteryx

has the perfect tools to hunt
for insects among the trees.

And one of its favourite foods

are burrowing beetle grubs
that are hiding

within the trees themselves.

Prey like this, which is difficult
to catch, is quite a prize...

a prize that can attract
unwanted attention.

Here it's another, larger,
Epidexipteryx.

Stealing food is a common tactic,

particularly where an animal
possesses an expertise.

There is more
to this extraordinary creature

than first meets the eye.

Not only was it perfectly designed
for life in the trees,

but the fossil has also revealed

that it was covered in short,
simple feathers.

Feathers that were likely to have
evolved for just one reason...

to keep it warm.

But there is one last
striking feature...

four long feathers on its tail.

These feathers
aren't like those of modern birds.

These are long and ribbon-like.

Almost certainly, only for show.

They're the earliest record
of ornamental feathers.

Not just for attraction

but also to threaten.

In fact, the very name Epidexipteryx
means "display feather",

and they're among the most
bird-like of any dinosaur.

Stealing among the trees
is one thing.

Stealing on the ground
is quite another.

Only among the trees
can you be safe

from the large predators
like Sinraptor.

On the ground, a few feathers
offer no protection.

The first feathered dinosaur
was discovered in 1996

but lots more would quickly follow.

It suddenly appeared as if
many dinosaur species

actually had feathers.

And confirmed what had
long been suspected...

a direct link between
dinosaurs and birds.

A link that can be found
in the dinosaurs that

lived here in the Mongolian
desert 85 million years ago.

This is Saurornithoides.

It's a member of the Troodon family
and we have discovered

actual fossils of these dinosaurs
sitting on a nest.

It takes days to
lay a full clutch of eggs

and until that's complete,

this animal won't
begin its brooding behaviour

and start sitting on the next.

With the Saurornithoides
off foraging,

this unguarded nest provides
an invitation for predators.

This is an Oviraptorid - a
bizarre-looking theropod dinosaur.

With no teeth,
they were mostly plant eaters.

But that doesn't mean
it won't take advantage

of a different kind of lunch.

We know Oviraptorids
were mostly plant eaters

because of some amazing evidence
we have found.

One fossil in particular
was incredibly well preserved.

Inside its body
were small stones - gastroliths.

Just like a bird,

it had swallowed these
to help digest tough plants.

But when the remains
of two unrelated embryos

were discovered
in an Oviraptorid nest,

it suggested that some
were not just plant eaters

but may have been nest-raiders
as well.

With two bony projections
in its upper jaw,

this Oviraptorid has the tools
to break into an egg

and get at the precious
contents inside.

It means that a nesting animal
like a Saurornithoides

can never turn its attention
away for long.

But two lost eggs
are the least of its problems.

Here, some nest raiders
are bigger than others.

This is Gigantoraptor.

Gigantoraptor was discovered in 2007
in the Gobi Desert of Mongolia.

The sheer size of the bones

revealed it was unlike
anything found before...

eight metres long and weighing
around 1.5 tonnes.

From its bones, we know

it was 35 times bigger than
its closest Oviraptorid relatives.

And yet this giant
wasn't even fully grown.

It was "like finding a mouse
the size of a cow".

We don't know for sure

if such a huge dinosaur
like Gigantoraptor

would have or need feathers.

In dinosaurs, feathers are usually
found as a fine body covering

and appear to be
mainly for keeping warm.

But feathers were found,
and preserved on a fossil

of one of Gigantoraptor's
close relatives.

And on the forearms and tail
are the unmistakeable traces

of longer symmetrical feathers,
similar to a modern bird's.

It seems certain that Gigantoraptor
too was feathered,

making this the largest feathered
animal ever discovered.

These aren't for flight -
Gigantoraptor couldn't fly.

Nor are they for insulation.

These are used to intimidate
or attract.

Across the world,
discovery after discovery

has revealed more
and more features...

from nesting to feathers -
that were once thought of

as exclusively bird-like but have
now also been found in dinosaurs.

But the ultimate discovery
is perhaps that of a dinosaur

that lived in Northeast China
around 120 million years ago.

This remote area has revealed

spectacular fossils
in exquisite detail,

unearthing an astonishing
diversity of animals,

many of which are well adapted
to living in trees.

One particular dinosaur discovery
takes this to a whole new level.

This is Xianglong.

With curved claws, it's a lizard
well suited to climbing trees.

With prey like this,
predators were sure to follow.

The most common dinosaur
in these forests

doesn't live on the ground.

Microraptor.

The fossils of Microraptor
are so well preserved

they clearly reveal every detail
of its anatomy.

With distinctive claws
on its first toe,

this is a member
of the raptor family.

But these claws evolved
for climbing, rather than killing.

At less than a metre long,

this was a dinosaur perfectly suited
to live in the trees.

Microraptor is small, and perfectly
adapted to chasing prey.

Xianglong, however, has a trick.

This is a flying lizard.

It seems to have the perfect skill
to escape.

But the fossils of Microraptor
reveal something else.

This was a feathered dinosaur,

but these feathers aren't
for keeping warm or for show.

Their structure is plainly
visible from the fossils.

They are very long, veined
and most importantly,

their shape creates a perfect
aerodynamic surface.

And they aren't confined
to its forearms.

Its legs, too, had long feathers.

These feathers are designed
for one thing only - flight.

Microraptor is
a four-winged dinosaur...

that took to the skies.

But in these Chinese forests,

Microraptor isn't the only
flying monster.

Sinornithosaurus.
Closely related and larger.

More than capable of stealing prey.

But it has larger prey in mind.

Microraptor is now the hunted.

Both can fly.

But this isn't powered flight -
it's gliding.

Recent research has revealed
how Microraptor flew.

It didn't have the muscles
for powered flight,

so instead it made
the most of its four wings.

By holding its rear legs back
and to the sides,

it was able to become an incredibly
efficient glider...

moving through the forest in a
series of long, looping glides.

Having longer flight feathers
on both its arms and legs,

Microraptor is by far
the better glider.

But with no ability to gain height,
the only way is down.

And once on the ground,
the long feathers

turn from an advantage
into weakness.

Microraptor is barely able
to walk, much less run.

Sinornithosaurus
has no such problem.

On the forest floor,
the tables are turned.

Microraptor has a fortunate escape.

Sinornithosaurus was one of
the first feathered dinosaurs found.

The fossils are so perfectly
preserved

they have helped us solve

one of the great dinosaur
mysteries.

For years, the colour of dinosaurs

was thought impossible to work out.

In 2010, it was discovered
that the feathers on this fossil

weren't just impressions.

Under the microscope,
tiny structures were revealed

identical to those
found in modern birds...

structures that contain
the pigment.

Remarkably,
by comparing them to living birds,

we can even work out
the true colours.

The feathers appear to be
a combination of reddish-browns,

yellows, greys and blacks,

perfectly suited to forest life.

Another dinosaur living
in this forest is Jeholosaurus,

a small plant eater.

Recent fossils indicate
that this type of dinosaur

looks after
and protects its young.

With feathers that allow it
to blend in with the forest,

Sinornithosaurus can move, unseen,
through the tree tops.

And Sinornithosaurus is a hunter
with a potent secret weapon.

In 2011, a study of the eyes
of this creature revealed

that it was a predator
perfectly capable

of hunting equally
during day and night.

And a study of its teeth, in 2009,

showed something that definitely
sets it apart from birds.

Something far more deadly.

The greatest danger
is not simply being outnumbered.

We have found that
Sinornithosaurus teeth

have unusual and distinctive
grooves along their length.

They resembled those of
the venomous Gila monster,

the grooves in its teeth used to
deliver venom into its victim.

The team even identified what
they thought was the location

of the venom sac in the fossil.

It appeared Sinornithosaurus
could kill with poison.

This is a far more deadly predator
than anyone ever imagined...

and completes an extraordinary
picture of a bizarre lost world.

All of these discoveries
reveal the importance of feathers

to a whole host of dinosaurs...

from insulation to defence
and finally, flight.

And Microraptor not only
hints at how flight developed,

but also, that dinosaurs still
live amongst us today,

as birds.