All language subtitles for Earth s01e01.eng

We are entranced
by the beauty of our planet.

Just take in this view
for a moment.

Lush green meadows, thick forest,
jagged mountain peaks -

it's magnificent.

But whilst we appreciate
that beauty,

I think sometimes we forget that
all of this is so fleeting.

For the last four-and-a-half
billion years,

our Earth has been a constantly
changing ball of rock,

transforming itself
over and over again.

It's more fragile
than we like to acknowledge.

It's more indifferent to us
than we care to admit.

Now, thanks to pioneering
new science,

we can explore our planet's
four-and-a-half-billion-year story

like never before.

In this series, we'll witness
five pivotal moments

in Earth's history...

..moments of drama...

..of crisis...

..and of rebirth...

..events that shaped
the planet we live on.

Wherever you are, you have beneath
your feet the most precious object

in the universe -

a living, breathing,
life-sustaining world.

And this is its story.

It can feel as if our living world
was somehow inevitable...

..that ours is a planet
with all the right ingredients

for a rich assortment of life...

..not only to arise,
but to flourish and endure.

But, in fact, it's death that is
the only true inevitability.

There's an uncomfortable truth
about life on Earth.

You see, this great diversity,
this weird, wonderful

and beautiful mix of species,
of plants, animals and fungi

are all only here because
something else has died -

in fact, because an enormous number
of other things have died.

If we were to take the sum total
of every living thing

on our planet today, it would add up
to less than 1% of those

that have ever existed on Earth.

But this colossal loss of life
is not a tragedy.

Extinction is a vital part
of evolution.

If nothing ever went extinct,

there would be no room for
new species to evolve.

Over time, extinction helped create
our rich living world.

But our planet walks a tightrope.

If extinction goes unchecked,

the complex web of life crumbles.

Imagine 90% of species
suddenly dying -

not just a few endangered plants
or animals becoming extinct,

or a handful of
ecosystems disappearing,

but nine out of ten living things
wiped off the face of the Earth.

Imagine what that Earth would
look like in the aftermath -

shattered, broken,
bereft of the beautiful complexity

that we take for granted today.

We may think modern climate change
is our planet's darkest hour,

or the loss of the dinosaurs,

but the Earth has seen worse.

This is the story of the greatest
mass extinction event

in Earth's history.

Something caused our planet's
life-support systems to fail,

wiping out most of
the species on Earth.

And this is not
an apocalyptic vision,

not a doomsday prophesy.

This actually happened.

252 million years ago,

the Earth turned on the life
that it had nurtured for so long.

What does it take to destroy
almost all life on Earth?

And could it happen again?

Well, the answer lies in
Earth's deep history...

..in a time long before humans
transformed the planet's surface...

..before the last Ice Age...

..before the asteroid impact
wiped out the dinosaurs...

..in fact, back to a time
before dinosaurs

even existed at all.

From space, the Earth in the
Late Permian is a strange sight.

From one side, a water world,

no land in sight.

But as the planet turns,
something else creeps into view...

..all the Earth's major landmasses
clustered as one.

This is Pangea...

..a supercontinent rich with life.

Coastal waters teem with weird
and wonderful creatures.

At once both alien,

yet eerily familiar.

And in lush forests, a cacophony
of animal cries fill the air.

In many ways,
the Earth in the Late Permian

was like the Earth we have today -

millions of species of plants
and animals, living together

in complex, interconnected webs

which are nurturing
and self-sustaining.

But in other ways,
it was a very alien world.

This was a time long before mammals
or even dinosaurs walked the Earth.

But life was no less remarkable.

Scuttling around in the scrub
of the Late Permian,

you might have found one of these.

This is the cast of a beautiful
fossil of Nycteroleter.

It's part of an extinct group of
reptiles, and fed on things

like proto-cockroaches,
dragonflies, millipedes.

It's got quite large eyes,

suggesting that it might have
been nocturnal,

and we also know that it had
really good hearing -

something quite unique
for animals of that time.

But then, look at this chap.

It's Dvinia.

It would've grown to about
50 centimetres.

Looked like a small dog.

Neither a mammal, nor a reptile,
it's got forward-facing eyes.

It was perhaps
a predator of some kind.

But, look, from the top, you can see
it's got really wide cheeks,

and the remains here of perhaps
a sagittal crest,

suggesting that it had very
powerful muscles, a powerful bite.

In fact, it might have been fishing
for shellfish down on the beach

and crunching them up with
its powerful jaws.

But last, and perhaps
most impressive,

this is a magnificent specimen of
a super predator, Inostrancevia.

What an animal.

Just look at those
sabre-tooth teeth there.

Now, those are slashing tools.

Those are for wounding prey,
waiting for it to bleed to death,

and then catching up with it
and swallowing large chunks whole.

This animal would've grown
to about 3 metres in length

and very fast-moving

and been terrorising
the large herbivores of its time.

What a fantastic beast
it must have been.

But by the end of the Permian,

along with nearly every other
living thing on Earth,

they would be dead.

We're not certain how it started,

but deep inside the ancient Earth,

superheated rock is rising...

..pushing upwards against
the solid outer crust...

..until it can take no more.

The crust fails.

The landscape physically torn apart,

as lava floods onto the surface...

..forming great curtains of fire.

This is just the beginning of
the most deadly volcanic event

in Earth's history.

We can get clues to what
these ancient eruptions were like

by studying modern volcanoes.

This is Tajogaite Volcano,
in the Canary Islands,

and in September of 2021,
the ground here split

and tonnes of lava, ash
and toxic gases exploded,

shaking the entire island.

Over three months,

170 million cubic metres of lava
poured onto the surface.

It was the first eruption
on the island in 50 years.

More than 7,000 people had
to flee their homes.

This volcano spewed out
enough lava to fill around

70,000 Olympic-sized swimming pools,

and that lava covered an area around
ten square kilometres -

which sounds pretty impressive,

but it's just a teaspoon compared
to those at the end of the Permian.

252 million years ago,

around four million cubic kilometres
of lava, ash and toxic gases

erupted in a series
of volcanic explosions

that went on for 2 million years.

The Permian eruptions
were 1,000 times greater than

any witnessed by humans.

And the ancient lava
is still with us.

In Northwestern Siberia,

beneath a landscape of swamps
and flood plains,

scientists have discovered
a colossal lava field,

dated a little over
250 million years old...

..lava that covers over
two-and-a-half million

square kilometres...

..enough to bury the entire
continent of Australia

hundreds of metres deep.

252 million years ago,
Northern Pangea was hell on Earth.

Fire fountains blast volcanic
material over six miles up

into the atmosphere...

..burning millions of square miles
of forests.

And clouds bloom high into
the atmosphere,

blocking out the sun.

Plants wilt and die...

..ash falls like snow...

..as vast swathes of Northern Pangea
lie in ruins.

These eruptions are on a scale
almost beyond imagination.

But lava still only covers
less than 1% of Pangea's surface.

And elsewhere, something curious
is happening.

A strange haze hangs in the air.

Nutrient-rich volcanic ash
and sulphur,

transported thousands of miles,
reflect the sun's rays...

..pushing global
temperatures down...

..and in places, causing a surge
of plant life to flourish.

But death is coming.

I've come to an outcrop
in Northern Italy,

made of rock that formed at the same
time as those ancient eruptions.

It's a fossilised crime scene

with a chilling tale to tell.

Look at this thin, black seam
that runs all the way down here.

It looks like coal to me,

which would indicate that
at one point...

..it was full of plant life.

Probably full of lots
of other life, too.

Coal is little more than
ancient organic matter

that's been subjected to
extreme temperatures and pressures

over millions of years.

So, where we find coal today,

we know there was once life.

But the rocks above it here
tell an altogether different story.

They're grey, dull,
look a bit boring,

a bit of a geological mush.

But that's the point -

because, aside from a few
fossil microorganisms,

scientists have found very little
evidence of life in these rocks.

So, what they are telling us
is that 252 million years ago,

the landscape here
was almost devoid of life.

In a geological blink of an eye,
almost all life here vanished.

You can't help but feel
a certain sense of sadness.

Holding this makes it so tangible.

This was death on
an unimaginable scale.

But there's no evidence of lava here
at all.

When these rocks were laid down
in this part of Italy,

they were thousands of miles away
from the eruptions in the north -

certainly too far away
for any direct impacts.

But what's interesting
is that geologists

have found this line of death
all over the planet -

China, Australia, South Africa.

And no matter how far away
from the lava fields,

there's a deathly silence
in the fossil record.

The question is, what could have
killed this many creatures?

What could have wiped out
almost all life on Earth?

Something more than lava
was emerging from the Earth

in Northern Pangea.

Billions of tonnes of gases are
injected high into the atmosphere.

Water vapour, sulphur dioxide...

..but primarily a gas
we all know too well -

the greenhouse gas
carbon dioxide.

We're all becoming depressingly
familiar with what happens

when you pump huge quantities of
carbon dioxide into the atmosphere.

It's an experiment we've been
running ourselves

for more than 100 years.

And the more the CO2,
the more the heat is locked in,

and the hotter our Earth becomes.

Global warming isn't
a localised effect.

The whole planet feels the burn.

Here we are, yeah, dead ahead.

No creature is safe.

You've got a little feeding party
taking place here at the moment.

Oh, look at that!

Oh, yes, yes!

Sorry to be a child,
but it's always...

Oh, oh, oh, oh!

Oh, I just saw it catch a fish!

Oh!

There are several species here.

Bottlenose...

..common, rough tooth, spotted.

And dolphins, of course, can live
in much warmer waters than these.

So, you might imagine
they're not the sorts of creatures

that would be harmed
by global warming.

But sadly, I've got to tell you,
these dolphins are in trouble.

It's not always the temperature
that poses a danger to life.

In fact, for some,
the heat is a blessing.

Let's see what
I've managed to catch.

Wow, rather a lot.

This mass of detritus here
is plankton,

much of it phytoplankton, algae.

Now, most of the organisms
wouldn't hurt anything,

but there is one species,
Karenia Brevis -

well, that's an algae
with a superpower.

You see, when the water
warms up here,

it goes into a reproductive frenzy,

producing blooms
many hundreds of times greater

than it normally would.

But what's good for the algae,
it turns out,

is not so good for the dolphins.

Because recent research has shown
that this is extremely toxic.

So, the small fish eat the algae,

the bigger fish eat the small fish,

the dolphins the larger fish.

And this organism
has been implicated

in the deaths of dozens of dolphins,

found dead floating in the sea here.

Rising temperatures affect
different parts of the food chain

in different ways,

throwing ecosystems
out of balance...

..often with deadly results.

You see, when it comes
to global warming,

it's not the actual heat
that kills those creatures.

It's the increases or decreases
in plant or animal populations

which disrupt those long-evolved,
stable, beautiful ecosystems.

Death by global warming
is not short, sharp, and painless.

It's prolonged and torturous.

As the temperatures rise
across Pangea...

..trees begin to die.

Holes appear in
the once-thick canopy,

bathing the ground in sunlight.

For some, it's an opportunity.

Weed-like plants flourish,

like spore-bearing lycophytes.

No longer struggling in the shadows,

in times of stress, they thrive.

And foreign species appear.

Woody, seed-bearing cycads
that once only grew in the tropics

are now abundant
closer to the Poles.

Surprisingly, some areas
are now more diverse

than before the warming began.

But this is an ecosystem
out of balance.

A few more degrees' warming,

and the living world will crumble.

But then something strange happens.

Red hot rivers of lava...

..turn to solid rock.

Just as quickly as they started,

the eruptions fall silent.

The CO2 released
from the Permian lavas

likely dwarfed human emissions
to date.

But even that may have been
just part of the story.

These eruptions would have produced

an inordinate amount
of carbon dioxide -

gigatons of the stuff,

certainly enough to manifest
some global warming,

perhaps in the realm of an increase
of 5 or 6 degrees Celsius,

something like that.

Now, that's a substantial amount
of heating,

but it's not significant enough
to account for all of the deaths

that we see in the fossil record.

Yes, there would have
been extinctions,

but not 90% of all life on Earth.

The effects of carbon dioxide
can be lethal.

But some scientists think
there was another killer.

The volcanism hadn't stopped.

It had just entered
a terrifying new phase.

Beneath the desolate lava field...

..hot magma still flows,

forming great reservoirs
underground...

..and slowly baking
the Earth's crust.

The rocks underground were older -

hundreds of millions of years
older than the land above.

And amongst them,

there was plenty of this stuff -

coal and other rocks rich in carbon.

Now, what happens
when magma meets coal?

Well, the coal burns, releasing
yet more dangerous carbon dioxide.

But that was just the half of it.

You see, it wasn't just coal.

There was also lots of salt.

And salt like this can form
when ancient lakes and seas dry up.

And when magma comes into contact
with salt,

things get really nasty.

The salt begins to bake,

releasing toxic halogen gases
rich in bromine and chlorine -

archenemies of the Earth's
fragile ozone layer,

that thin layer that protects us
from the sun's most harmful rays.

So, what I'm trying to say here
is that the magma had found its way

into the worst possible place
on the planet.

It had created a time bomb.

That magma begins to
heat up the coal and salt

to a temperature of
800 degrees Celsius.

A poisonous cocktail of gases
begins to build...

..until the land above
can take no more.

More CO2 floods the atmosphere,

pushing global temperatures
even higher.

But this time, there were also
those toxic halogen gases.

We've seen the Earth's ozone layer
damaged in recent history,

when artificial chemicals
created a so-called ozone hole.

But in the Permian,
the halogens may have eroded

the ozone layer away entirely...

..bathing all life
in deadly UV radiation.

Scientists have noticed something
strange going on with the pollen

at the end of the Permian.

Take a look at this.

This is a highly-magnified image
of a modern pine pollen grain.

And you can see it's got two
essential parts to its structure -

the central circular part here,
the corpus,

and then these winged sacchi.

These are wind-pollinated
pollen species,

and these help it float
through the air.

But have a look at this.

This is an image of a fossilised
coniferous pollen grain

from the time of those eruptions.

It's got three of these
wing structures.

This one has four.

These pollen grains are malformed,
misshapen and, in fact,

if you look at this last one,

this appear to have been
in the process of dividing,

but somehow it's failed.

These are mutant pollen grains,

and it's thought that
the mutation was caused by

the excessive UV radiation -

evidence that those gases had really
damaged the Earth's ozone layer.

Now, other theories are available.

Others believe that, in fact,
it was acid rain

that caused these mutations,
or merely the extreme heat.

But whatever the cause,

what's clear is that at this point,
life was on the brink.

At first glance,
it seems nothing has changed.

But this already fragile ecosystem

has taken a lethal dose
of UV radiation.

Healthy-looking plants
are now sterile.

As individuals die,
they aren't replaced.

Once-lush forests
become ravaged wastelands.

The collapse in the oceans
is even more dramatic.

Carbon dioxide reacts
with sea water,

which begins to turn to acid.

And oxygen levels plummet -

in some places, dropping to zero.

Algae blooms across the planet.

As it decomposes,
it poisons the ocean

with toxic hydrogen sulphide...

..until the seafloor becomes
a foetid bed of slime.

Sulphurous tides lap barren shores,

and a smell like rotten eggs
hangs in the air.

The Earth's rich complexity
has vanished,

seemingly for good.

It's been called many things -

the Great Dying, the mother of
all mass extinction events

or, simply, when life nearly died.

The details are still a bit hazy.

Was it a single short, sharp,
giant catastrophe,

or a wave of smaller catastrophes?

To what extent did the extinctions
occur on land

versus extinctions in the water?

The fossil record is patchy,

so there's plenty of room
for academic debate.

But the one thing that
almost everyone agrees upon

is that these ancient eruptions
caused extinctions

on an unprecedented scale.

Figures frequently cited suggest
that 70% of land vertebrates

and 96% of marine life

vanished off the face of
the Earth forever.

By the time the eruptions
finally stop,

the average global temperature has
risen by over 10 degrees Celsius.

Vast areas of the Earth's surface
are completely uninhabitable,

and nearly all species are gone.

The End-Permian extinction
has a virtually undisputed claim

to being the worst moment
in the history of the Earth.

But from the ashes,
there was a glimmer of hope,

because life had survived somewhere.

It must have.
Otherwise, we wouldn't be here.

In a way, we are all survivors
of the Great Dying.

You see, every living organism on
the planet has an ancient ancestor,

perhaps millions, perhaps billions
of generations back,

that not only survived
that mass extinction event

but then went on to prosper
in the aftermath

and then to repopulate the Earth.

The Great Dying may have been
the end of one world,

but it was also the beginning
of a new one.

The Triassic Earth
is a shadow of its former self.

Many creatures
seek refuge underground...

..sheltering from
blistering temperatures

and lethal UV radiation.

Above ground, a single plant species
dominates the landscape.

Pleuromeia - a weed-like plant
lucky enough to make it

through the apocalypse and
find itself with few competitors.

It helps provide sustenance
for the cockroaches,

who also made it through unscathed.

But just because
the eruptions have stopped

doesn't mean that life's troubles
are over.

The Early Triassic was dominated
by extreme heat.

The fossil record shows us that
ocean temperatures could have been

up to 14 degrees centigrade warmer

than they were prior
to the eruptions.

In some places, the water was
as warm as it is in a hot tub -

too extreme for most
marine organisms.

And on land, things weren't
faring much better.

There were probably heatwaves of
up to 60 degrees centigrade -

a temperature that would have
seriously inhibited photosynthesis.

In fact, for the 10 million years
following the mass extinction event,

we see no significant coal reserves
laid down anywhere on Earth.

There simply weren't enough trees.

For life to bounce back,
the planet needed to cool down.

In normal times,
the Earth can cool itself -

over thousands of years,
removing carbon dioxide

from the atmosphere, in part
through reacting with rainwater.

But vast areas of Pangea are desert.

Little rain falls.

So, it takes millions of years
for temperatures to drop.

And even then, recovery is slow.

The living world's struggling to
regain the diversity it once knew.

But salvation was coming.

High in the Dolomite Mountains
is evidence for a bizarre event,

one that may have helped
life rebound.

Look at this.

Absolutely stunning.

And these mountains were formed very
shortly after the extinction event,

and they're made up of
sedimentary rock -

layers of sediment on top
of one another,

each corresponding to a time
in the Earth's history.

The oldest rocks are at the bottom,

around 238 million years old.

The youngest at the top,

about 200 million years old.

Now, you might imagine that
if we wanted to uncover the secrets

in these rocks, we'd take some,
break them open

and look for some details -
but not here.

The secrets in these rocks
are held in plain view.

The key is the shape
of the mountains.

It hints at a planetary intervention
that, just a few decades ago,

we had no idea happened.

Look, it starts steep at the bottom,
rises sharply,

and then there's a shallow shelf,

and then it rises steeply again
to the peak,

currently in the clouds.

But the bit that we're interested in
is that shallow slope,

which corresponds to about 2 million
years in the Earth's history,

and to a very strange
period of time.

This shallow slope is evidence
of a softer rock type

that's been eroded over the years.

Here we go.

This is a lump of sandstone.

It's a soft sedimentary rock.

The key is in the name.

It's made up of sediments, like
sand, which wash off of the land,

down into the rivers
and then down into the sea.

So, what I'm holding here
is evidence of rain -

rather a lot of rain,

because in places,
this layer is about 80 metres deep.

Sandstone is a common rock,

but scientists have discovered
similar layers

right across the planet,

leading some to think this was
the result of a global deluge.

Now, we're not precisely sure
why it started.

It could have been
underwater volcanic activity

disrupting the water cycle.

But at some point in the Triassic,

a time famed for being
excruciatingly hot and arid,

it started to rain.

And, boy, did it rain -
because that rain

defined the Earth's climate
for almost 2 million years.

18 million years
after the mass extinction,

the heavens open...

..a sudden increase in rainfall
across Pangea.

The rain causes more extinctions...

..but the planet is reborn.

Where arid shrub land once stood...

..lush forests now grow.

It's been called
the greening of Triassic Earth,

and it marked the beginning
of much of the life we know today.

There were new species
of crocodiles...

..amphibians...

..even early ancestors
of modern mammals.

But the mammals would have to
wait in the wings.

Other creatures were set
to inherit this renewed world.

Look at this.

See this impression
in the rock here?

Look, there are one, two,
three toes.

This is a dinosaur footprint,

and I love the fact that
I can put my hand

where a dinosaur once put its foot.

Now, whether dinosaurs existed
before the rains, we can't be sure.

If they did, it was only
as an obscure group

in the south of Pangea.

But in the millions of years
after the rains,

they certainly prospered.

In some places, 90% of the
vertebrate fossils are dinosaurs.

Why did they suddenly do so well?

Well, it could be down to the food.

They could use it more efficiently
to grow bigger more quickly.

But whatever the reason,

dinosaurs went on
to dominate the Earth.

I love this!

By the end of the Triassic,

the stage is set for the reptiles
to rule supreme.

This will be their world
for the next 140 million years.

The age of the dinosaurs is dawning.

In one way,
the End-Permian extinction

exposed the fundamental fragility
of life.

Countless species of plants
and animals were wiped out

by those volcanic eruptions,

and it took millions of years
to recover.

But perhaps the event also taught us
another lesson

about the tenacity of life -

because the living world did
bounce back, to be just as complex

and just as beautiful,
in fact, maybe even more so.

But there's a big
unspoken question here.

For over 100 years, we've been
pumping carbon dioxide into

the atmosphere and watching
as global temperatures creep up.

So, what can the mass extinction
252 million years ago teach us

about our own climate change event?

I think the big lesson we've just
learned is that the living world

will ultimately be fine.

Even if we don't address
our climate and biodiversity crisis,

if we burn every last lump of coal
and drop of oil,

if we leave this place
as a complete hellscape,

whilst we might perish,
life will bounce back,

and this will all be
beautiful again -

which begs the question,

"Should we bother to preserve
and protect it?"

Well, that extinction event
252 million years ago

was part of a planetary process.

It was a chance volcanic eruption.

Think of all of that suffering.

Think of all of that wastage.

Do we want those sorts of
extinctions on our conscience?

I don't think so.

In this episode, we saw how
an Earth-shattering eruption

destroyed almost all life on Earth.

This is the closest
our planet has ever been

to going back to square one.

To understand the scale
of the event,

scientists mapped
the Permian lava fields of Russia -

known as the Siberian Traps.

I have actually been to
the Siberian Traps

and flown helicopters.

The helicopter is right, mm...there.

Floated on boats, hiked,

ridden on trains
all over Arctic Siberia,

looking for remnants of
the Siberian Traps.

And these lava flows go distances
that boggle the mind.

The 1 million cubic miles that we
have is probably a minimum number,

and it's a minimum
because not all of the rocks

are exposed at the surface.

We also sampled the rocks of
the Siberian Traps

with sledgehammers and rock hammers

and a lot of hard work.

The rock samples were key
to understanding

why the Earth's climate
changed so dramatically.

When magma comes up from
deep within the Earth,

it has gases dissolved in it,

gases like carbon dioxide
and sulphur dioxide.

These gases come out into bubbles,

a bit like when you take the lid off
a soda bottle and it fizzes.

But these gases told
a contradictory story.

Sulphur dioxide and carbon dioxide
have opposite effects

on the Earth's atmosphere.

Sulphur dioxide reflects sunlight
back into outer space,

causing global cooling,

whereas carbon dioxide
is a greenhouse gas

and can lead to global warming.

It turns out that different volcanic
gases hang around in our atmosphere

for different amounts of time

because of their different
chemical properties.

Sulphur dioxide tends to stay
in the atmosphere

for a shorter period of time,

because it can get rained out.

But carbon dioxide can stay in
the Earth's atmosphere for hundreds,

if not thousands of years.

Scientists think that
heat-trapping carbon dioxide

would have built up in
the atmosphere, warming the planet.

And there were other clues
in the fossil record.

So, we can measure what
temperatures were like in the past

by the study of fossils,

and particularly
fossil bone material.

So, when the bone is formed,

it's partly controlled
by the temperature.

And so by studying these bones,
we're able to see

what the temperatures were like
back in the past.

Temperature rises of up to 7 degrees
brought a deluge of rainfall.

Known as the Carnian
Pluvial Episode,

some scientists think
these conditions were essential

to the success of the dinosaurs.

My research suggests that more rain
means it's better for the plants.

This era of warm, wet conditions
really boosted plant diversity.

More plants equals more insects,
more plant-eaters,

and then you get more meat-eaters
as well,

and dinosaurs are part
of that growth.

So, this is Herrerasaurus.

This is one of the first dinosaurs
to appear.

And as you can see
by the sharp teeth here,

this was a meat-eater,
one of the top predators.

The evidence for this growth
is written in the rock record.

The success of the dinosaurs
after this event is seen in

just an abundance of their fossils,
but also in their sort of indirect

records that they leave in the forms
of their footprints as well.

Before the Carnian Pluvial Episode,

dinosaurs and their relatives only
made up around 5% of the footprints

at these different fossil sites.

After the Carnian Pluvial Episode,
we see a big increase -

it jumps up to 70%.

The explosion in the population
of dinosaurs

is a brand-new area of research.

We can see that the ecosystems
were changing,

but what actually would've
affected the dinosaurs,

what would've caused them
to be successful,

we don't know yet.

This is why there's
so many palaeontologists

doing active research.

Next time...

..we journey deeper into the past,

to witness one of the strangest
moments in history...

..a global deep freeze..

..that transformed the Earth...

..into an ice world.

If the Earth could talk,
what would it tell us?

Well, the Open University imagine
how it might answer

some of our questions.

To experience
this interactive presentation,

go to the website on the screen
and follow the links

to The Open University.

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