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[ominous music playing]
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[Morgan Freeman] Millions of years
before the age of dinosaurs...
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our planet was ruled
by equally magnificent beasts.
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[low grunting]
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Two great dynasties had emerged
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and were vying for domination.
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[wailing]
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This is the story
of the battle to conquer land...
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[growling]
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...and how it changed everything
for life on our planet.
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[roaring]
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{\an8}[rousing music playing]
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{\an8}[snarling]
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{\an8}[trilling]
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{\an8}[screeching]
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{\an8}[rousing music continues]
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[growling]
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[wind howling]
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{\an8}[rumbling]
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[rousing music intensifies]
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[music fades]
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{\an8}[somber music playing]
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For most of our planet's history,
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land has been inhospitable to life.
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A bleak and desolate realm...
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more like the surface of the moon...
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than like Earth today.
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It's hard to imagine
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how anything could ever make
this hostile place its home.
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But from beneath the waves,
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where life had thrived
for more than a billion years,
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one curious life-form was among the first
to rise to the challenge.
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Lichen may not look remarkable,
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but they are in fact completely unique.
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A pioneering partnership.
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[intriguing music playing]
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Neither plant nor animal,
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lichen are a strange combination
of fungi and algae...
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that only together had what it took
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to overcome the extreme hostility
of barren Earth.
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[ethereal music playing]
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But they were more than just pioneering.
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They were groundbreaking.
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As they spread...
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[stirring music playing]
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...their tiny filaments
helped to break down rock
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and produce the first ever soil...
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paving the way for plants to take over.
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Micro plants, like moss,
were first to appear.
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With leaves only one cell thick,
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they couldn't grow upwards,
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but could spread out.
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Reproducing faster than lichen,
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they soon carpeted the land,
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which they ruled undisturbed
for the next 40 million years.
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[music intensifies]
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[music fades]
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But a green revolution was coming...
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that would change the landscape forever.
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Key was the evolution of a new compound,
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lignin.
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Lignin strengthened
the plants' cell walls...
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allowing them to grow bigger and stronger
than ever before.
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No longer confined to carpeting the land,
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plants began to battle
for the real estate above,
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fighting for access to light.
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[dramatic music playing]
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[music fades]
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Eventually, some plants grew so tall,
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they towered above the world around them.
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[majestic music playing]
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Today's redwoods are nature's skyscrapers.
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Reaching heights
of more than a hundred meters,
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they are the tallest living things
to have ever existed.
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But redwoods are just one
of more than 400,000 species of plant,
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the most visible signs of life
on our planet.
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[music fades]
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Back in Earth's distant past,
the arrival of plants
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{\an8}created new habitats
for the next invaders from the sea.
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{\an8}[unsettling music playing]
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The first animals to ever set foot on land
were the arthropods.
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Relatives of the trilobites,
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their hard exoskeletons
had served as useful armor underwater.
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On land, that armor supported them
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and prevented them from drying out.
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They could also breathe
through this tough exterior.
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And with oxygen levels 60% higher
than they are today,
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some grew to be giants.
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Arthropleura, the largest millipede
to ever walk the Earth.
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At over two and a half meters long
and a half meter wide,
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he has no natural enemies...
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[peaceful music playing]
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...so can focus all his energy
on finding a mate.
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But for Arthropleura,
the pursuit of the perfect partner is
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not straightforward.
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- [soft thud]
- [music stops]
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For he's virtually blind...
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[music resumes]
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...and his world extends
only as far as he can sense.
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The fern forest is vast,
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and a female could be anywhere.
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But his search isn't as hopeless
as it might seem.
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Females ready to mate
leave scent trails for males to follow.
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A lifeline in the darkness.
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[whooshing]
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[pensive music playing]
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And yet, sensing where she once was
is not the same
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as sensing where she is.
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[whimsical music playing]
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[peaceful music playing]
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Finally, his chance to charm can begin.
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[chirping]
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By rubbing together parts of his shell,
he creates his own unique love song.
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- [music stops]
- [chirping continues]
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[peaceful music continues]
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[soft chirping]
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[music swells]
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Mating on land can be an awkward affair.
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Success requires the perfect alignment.
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So it's important at this critical stage
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not to put a foot wrong.
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[music intensifies]
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[music ends]
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[birds tweeting]
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345 million years later,
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and in today's forests,
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the arthropod art of seduction
has come a long way.
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Especially for some of the less armored
members of the group.
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[brooding music playing]
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Unlike the ancient Arthropleura,
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male jumping spiders have superb vision
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and are no larger than a grain of rice.
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[music becomes playful]
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But what they lack in stature...
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they make up for in style.
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Each species has
its own signature dance move
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to attract female attention.
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The peacock.
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The side shuffle.
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The disco dancer.
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And the feather shake.
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While the males evolved colorful costumes
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and intricate dance moves...
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females developed impeccable taste.
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His side shuffle has caught her attention.
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But has he got the moves
she's looking for?
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Only the very best will do.
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[lively jazz music playing]
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Waving her abdomen
signals she's not impressed.
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[dramatic music playing]
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[music fades]
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He needs to be careful,
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for fussy females
sometimes eat their suitors.
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[tense music playing]
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Still...
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[lively jazz music resumes]
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...it's worth one more try.
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[music slows, fades]
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Clearly, he's not getting the message.
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[tense music playing]
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He may be unlucky in love,
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but his arthropod dynasty
has had better luck.
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They now make up over 80%
of all animal species.
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The secret to arthropod success
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lies in their simple segmented body plan...
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[sinister music playing]
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...which has evolved
in countless different directions.
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[music intensifies]
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Some have ears in their legs.
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Others, eyes on stalks.
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And armor plating for battle.
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Variation after variation,
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arthropods are evolution run wild.
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Including the greatest runner of them all,
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the tiger beetle.
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Its design has been fine-tuned
over millions of years.
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The latest model is built for speed.
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For its size, it is
one of the fastest sprinters on Earth.
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If scaled up to human proportions,
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it would run
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at over 1,000 kilometers per hour.
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But there is one drawback
to life in the fast lane.
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His brain can't keep up.
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He must frequently stop
to get his bearings
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while hunting down his next victim.
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[tense music playing]
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But his frantic search for food
can lead him into dangerous territory...
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because sometimes the hunter
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can also be
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the hunted.
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[ominous music playing]
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Fast and furious
is not this trapdoor spider's style.
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She prefers to wait
for prey to come to her.
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[suspenseful music playing]
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[music intensifies]
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[dramatic music playing]
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[music fades]
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In the battle of the arthropods,
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flight would often make the difference
between life and death.
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[intriguing music playing]
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[buzzing]
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More than 300 million years ago,
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one group of arthropods
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were the first creatures
to take to the skies.
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[music intensifies]
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00:21:17,609 --> 00:21:19,528
And the evolution of wings
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would eventually launch them
to global success.
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The insects.
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[rousing music playing]
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00:21:36,044 --> 00:21:39,506
Today, for every human on the planet,
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there are more than a billion insects.
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They are the most abundant
group of animals on Earth.
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{\an8}[music fades]
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{\an8}[creatures chirping, insect buzzing]
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00:22:07,784 --> 00:22:10,203
Despite their current success,
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the ultimate flying insects first appeared
back in the ancient swamps.
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Dragonflies.
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Their flight is as close to perfect
as it gets.
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Four flexible wings,
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independently controlled,
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give them unparalleled mobility.
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00:22:41,568 --> 00:22:45,238
They can fly in any direction,
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pull off the tightest turns...
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[intriguing music playing]
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00:22:52,829 --> 00:22:56,375
and accelerate faster than a fighter jet.
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A winning design
that has remained almost the same
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for hundreds of millions of years.
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[music fades]
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00:23:12,599 --> 00:23:16,853
And yet, living in the same
prehistoric swamps,
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another group of animals
were undergoing their own radical change.
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00:23:26,822 --> 00:23:28,240
Beneath the surface,
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vertebrates had continued to evolve...
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00:23:35,580 --> 00:23:39,584
and a new type of fish was thriving,
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the lobe-finned fish.
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Some grew to be monstrous predators.
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[tense music playing]
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00:24:06,445 --> 00:24:09,573
In this fish-eat-fish world,
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it pays to be big.
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[music intensifies]
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00:24:18,373 --> 00:24:20,125
[music ends]
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00:24:21,418 --> 00:24:25,380
For the smaller ones,
there's refuge in the shallows...
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00:24:29,468 --> 00:24:34,514
where their unique lobed fins
are a distinct advantage.
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Muscular and highly versatile,
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they are different to those of other fish.
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Not only do they help them swim...
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00:24:53,325 --> 00:24:57,162
but they're strong enough
to support their body weight...
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00:25:00,790 --> 00:25:06,213
and help them crawl out of the water.
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00:25:11,009 --> 00:25:16,056
But these fish also have
another game-changing adaptation...
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the ability...
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- [wheezes]
- ...to breathe air.
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Not through gills
but through primitive lungs.
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Together, these evolutionary advances
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allowed vertebrates to leave the water
and explore the land.
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The race was on
to colonize this new world.
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00:25:58,473 --> 00:26:01,142
But it was already too late
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00:26:02,644 --> 00:26:04,896
for these lobe-finned fish.
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00:26:08,775 --> 00:26:11,736
Others had made this transition
before them.
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00:26:14,406 --> 00:26:15,448
[grunting]
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00:26:18,243 --> 00:26:20,245
[dramatic music playing]
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00:26:27,919 --> 00:26:30,922
Like the three-meter-long Anthracosaurus...
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00:26:31,965 --> 00:26:33,967
[low growling]
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00:26:34,634 --> 00:26:37,304
...that had already found its feet.
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00:26:37,387 --> 00:26:38,555
[grunts]
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00:26:47,981 --> 00:26:52,485
The evolution from fin to limb
took millions of years.
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[stirring music playing]
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00:26:57,949 --> 00:27:01,244
But once completed, life on land
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00:27:02,370 --> 00:27:04,623
would never be the same again.
268
00:27:18,136 --> 00:27:20,138
The age of amphibians
269
00:27:21,514 --> 00:27:22,641
had begun.
270
00:27:31,358 --> 00:27:34,110
[ethereal music playing]
271
00:27:40,909 --> 00:27:47,248
Today, there are more
than 8,000 species of amphibian.
272
00:27:50,543 --> 00:27:53,963
A peculiar but diverse group...
273
00:27:54,047 --> 00:27:56,091
[long croak]
274
00:27:57,676 --> 00:27:58,927
...of newts,
275
00:27:59,678 --> 00:28:00,845
frogs,
276
00:28:01,513 --> 00:28:02,847
salamanders,
277
00:28:03,765 --> 00:28:04,849
and toads.
278
00:28:05,850 --> 00:28:07,060
[music intensifies]
279
00:28:07,143 --> 00:28:10,105
Not quite the giants they once were,
280
00:28:11,022 --> 00:28:13,525
but still successful hunters...
281
00:28:13,608 --> 00:28:15,610
[music fades]
282
00:28:16,528 --> 00:28:19,864
...with their own killer style.
283
00:28:19,948 --> 00:28:21,950
[birds tweeting]
284
00:28:28,915 --> 00:28:32,335
Hundreds of millions of years
after Anthracosaurus,
285
00:28:33,461 --> 00:28:37,966
swamplands remain a stronghold
for amphibians.
286
00:28:38,049 --> 00:28:40,051
[tranquil music playing]
287
00:28:42,137 --> 00:28:45,390
Here in Europe's Danube delta,
288
00:28:45,473 --> 00:28:48,893
marsh frogs live in their thousands
289
00:28:49,686 --> 00:28:53,106
and have become expert insect hunters...
290
00:28:55,692 --> 00:28:57,819
with a particular taste
291
00:28:59,279 --> 00:29:00,905
for dragonflies.
292
00:29:04,659 --> 00:29:06,745
[tense music playing]
293
00:29:07,829 --> 00:29:09,956
Thanks to their wraparound vision,
294
00:29:12,459 --> 00:29:15,044
catching one isn't easy.
295
00:29:16,421 --> 00:29:22,552
But marsh frogs have evolved
some quirky adaptations of their own.
296
00:29:32,687 --> 00:29:35,732
Webbed feet help them get airborne.
297
00:29:44,115 --> 00:29:49,037
And a projectile tongue
gives them extraordinary reach.
298
00:29:57,045 --> 00:30:01,049
Even so, dragonflies in flight
299
00:30:01,132 --> 00:30:05,094
can be just too hard to catch.
300
00:30:10,099 --> 00:30:14,562
Waiting for the aerial acrobats to land
might make things easier.
301
00:30:53,560 --> 00:30:55,562
Time to take a different approach.
302
00:31:00,942 --> 00:31:05,154
A female laying eggs in the water.
303
00:31:10,785 --> 00:31:12,495
Half-submerged,
304
00:31:13,538 --> 00:31:16,165
she should be an easier target.
305
00:31:25,008 --> 00:31:26,759
[dramatic music playing]
306
00:31:44,986 --> 00:31:49,532
The dragonflies are just too fast.
307
00:31:53,411 --> 00:31:55,413
[suspenseful music playing]
308
00:32:02,045 --> 00:32:05,214
And they can barrel-roll.
309
00:32:26,611 --> 00:32:27,862
Missed again.
310
00:32:30,573 --> 00:32:35,203
But frogs are nothing if not persistent.
311
00:32:35,286 --> 00:32:37,288
[suspenseful music playing]
312
00:32:42,752 --> 00:32:44,337
[music ends]
313
00:32:50,009 --> 00:32:52,303
Despite the low hit rate,
314
00:32:52,387 --> 00:32:58,518
amphibians have survived
for over 350 million years.
315
00:33:03,022 --> 00:33:08,277
And yet, they never conquered
every environment the planet had to offer...
316
00:33:10,613 --> 00:33:15,827
because there's something
all amphibians need to raise their young.
317
00:33:19,122 --> 00:33:20,123
Water.
318
00:33:23,543 --> 00:33:27,213
This is the strawberry dart frog
of Costa Rica.
319
00:33:27,296 --> 00:33:29,007
[croaking]
320
00:33:33,094 --> 00:33:35,972
Her tadpoles are in mortal danger.
321
00:33:38,558 --> 00:33:41,853
Their tiny puddle, almost dry.
322
00:33:54,449 --> 00:33:56,034
[croaking]
323
00:33:57,452 --> 00:33:59,454
Their only means of escape
324
00:34:00,955 --> 00:34:03,041
is on their mother's back.
325
00:34:06,377 --> 00:34:09,630
The hard part is finding water.
326
00:34:14,177 --> 00:34:15,011
Luckily...
327
00:34:15,094 --> 00:34:17,096
[croaking]
328
00:34:18,931 --> 00:34:21,642
...she knows exactly where to go.
329
00:34:23,269 --> 00:34:25,855
[croaking]
330
00:34:28,316 --> 00:34:29,859
Twenty meters above her,
331
00:34:31,402 --> 00:34:33,863
a bromeliad collects rainwater.
332
00:34:37,283 --> 00:34:40,703
The perfect pool for her precious tadpole.
333
00:34:43,247 --> 00:34:46,292
But first, she must get there...
334
00:34:48,753 --> 00:34:51,881
one hop at a time.
335
00:34:55,259 --> 00:34:57,261
[invigorating music playing]
336
00:35:02,016 --> 00:35:05,103
Barely the size of a human thumbnail,
337
00:35:05,770 --> 00:35:09,107
this is her own personal Everest.
338
00:35:11,400 --> 00:35:13,277
[ethereal vocalizing]
339
00:35:28,376 --> 00:35:30,378
[croaking]
340
00:35:33,131 --> 00:35:35,133
{\an8}[music fades]
341
00:35:36,092 --> 00:35:38,010
{\an8}Safe at last.
342
00:35:39,303 --> 00:35:41,556
[croaking]
343
00:35:48,020 --> 00:35:52,316
No matter what great heights amphibians
reached in their conquest of land...
344
00:35:55,444 --> 00:35:58,364
they never escaped their tie to water...
345
00:36:00,408 --> 00:36:05,288
a tie that would be their undoing
when conditions on Earth...
346
00:36:07,331 --> 00:36:09,000
radically changed.
347
00:36:12,545 --> 00:36:14,797
{\an8}[ominous music playing]
348
00:36:21,721 --> 00:36:24,599
{\an8}During the period known
as the Carboniferous,
349
00:36:25,391 --> 00:36:28,686
Earth's great land masses merged,
350
00:36:28,769 --> 00:36:32,648
and the supercontinent of Pangaea
was born.
351
00:36:35,443 --> 00:36:37,111
As the land dried,
352
00:36:37,945 --> 00:36:40,531
the vast swamps began to disappear.
353
00:36:43,034 --> 00:36:47,288
Lacking water, most amphibians struggled.
354
00:36:48,956 --> 00:36:50,958
[music fades]
355
00:36:52,376 --> 00:36:53,669
But not all.
356
00:36:55,254 --> 00:37:00,676
One evolved a revolutionary adaptation
that enabled it to thrive.
357
00:37:06,474 --> 00:37:10,144
Its egg developed a protective shell
358
00:37:10,228 --> 00:37:15,149
that held the embryo
in its own private pool of fluid.
359
00:37:18,945 --> 00:37:24,700
Inside, the young could develop safely
without drying out.
360
00:37:25,701 --> 00:37:27,703
[serene music playing]
361
00:37:38,172 --> 00:37:43,010
The tie to water was finally broken
by the evolution
362
00:37:44,303 --> 00:37:46,555
of this amniotic egg.
363
00:37:52,812 --> 00:37:55,147
Known as the amniotes,
364
00:37:55,231 --> 00:37:58,651
these creatures
could colonize the drier land
365
00:37:58,734 --> 00:38:01,279
in a way that amphibians could not.
366
00:38:02,446 --> 00:38:04,448
[music intensifies]
367
00:38:06,659 --> 00:38:10,663
And from this one common ancestor,
368
00:38:10,746 --> 00:38:14,500
all mammals, reptiles, birds,
369
00:38:14,583 --> 00:38:18,087
and dinosaurs would descend.
370
00:38:18,170 --> 00:38:20,047
[sinister music playing]
371
00:38:52,204 --> 00:38:54,206
{\an8}[music fades]
372
00:38:57,293 --> 00:39:01,547
Sixty million years after the evolution
of the amniotic egg,
373
00:39:03,132 --> 00:39:06,135
amniotes have spread across Pangaea...
374
00:39:06,844 --> 00:39:09,347
[majestic music playing]
375
00:39:10,890 --> 00:39:16,812
...producing two new dynasties
and the start of an endless rivalry.
376
00:39:22,818 --> 00:39:28,491
These sleeping armored beasts
are a primitive type of reptile.
377
00:39:35,122 --> 00:39:40,252
Scutosaurus,
among the largest animals on land.
378
00:39:46,967 --> 00:39:48,260
[distant bellowing]
379
00:39:52,306 --> 00:39:53,724
[grunting]
380
00:39:59,605 --> 00:40:01,232
Weighing over a ton,
381
00:40:02,983 --> 00:40:06,362
they are the first giant plant-eaters
to roam the planet.
382
00:40:12,326 --> 00:40:16,664
Amniotic eggs allowed them to flourish
in the drier conditions
383
00:40:17,206 --> 00:40:20,000
and go where others could not.
384
00:40:20,709 --> 00:40:22,711
[low growling]
385
00:40:24,588 --> 00:40:27,466
But Pangaea didn't just belong to them.
386
00:40:33,139 --> 00:40:35,891
Another new bloodline had emerged.
387
00:40:36,892 --> 00:40:39,812
The ancestors of the mammals.
388
00:40:42,606 --> 00:40:44,066
[mewls]
389
00:40:47,862 --> 00:40:51,157
While a Lystrosaurus
is no match for a Scutosaur...
390
00:40:51,240 --> 00:40:53,576
- [growling]
- [mewls]
391
00:40:53,659 --> 00:40:56,537
...he has cousins here who are.
392
00:40:57,872 --> 00:41:00,040
[ominous music playing]
393
00:41:16,307 --> 00:41:18,309
[snarling]
394
00:41:20,769 --> 00:41:22,229
A gorgonopsid.
395
00:41:25,900 --> 00:41:29,320
A more impressive forerunner
to the mammals.
396
00:41:33,032 --> 00:41:37,661
At over three meters long and 300 kilos,
397
00:41:38,829 --> 00:41:42,082
she rivals any big cat alive today.
398
00:41:42,708 --> 00:41:44,710
[grunting]
399
00:41:48,589 --> 00:41:50,799
With her powerful sense of smell,
400
00:41:51,884 --> 00:41:54,011
tracking her prey is easy.
401
00:41:56,847 --> 00:41:58,891
Getting past their heavy armor
402
00:42:00,142 --> 00:42:02,144
will be her greatest challenge.
403
00:42:02,228 --> 00:42:05,064
[grunting, wailing]
404
00:42:08,442 --> 00:42:10,277
But she has a secret weapon.
405
00:42:10,361 --> 00:42:12,071
[snarling]
406
00:42:13,447 --> 00:42:15,074
Saber-like teeth.
407
00:42:22,581 --> 00:42:24,041
Even so,
408
00:42:24,875 --> 00:42:27,294
she'll need stealth to get close.
409
00:42:27,378 --> 00:42:28,504
[grunting]
410
00:42:39,181 --> 00:42:41,934
- [grunting]
- [wind whistling]
411
00:42:48,649 --> 00:42:50,651
[grunting]
412
00:43:01,078 --> 00:43:03,581
[tense music playing]
413
00:43:06,834 --> 00:43:08,752
She must choose her moment...
414
00:43:13,215 --> 00:43:14,550
and her target
415
00:43:16,385 --> 00:43:17,385
carefully.
416
00:43:17,428 --> 00:43:18,971
[grunting]
417
00:43:25,769 --> 00:43:26,812
Slowly
418
00:43:28,397 --> 00:43:29,815
and silently...
419
00:43:33,193 --> 00:43:34,320
does it.
420
00:43:34,403 --> 00:43:36,238
[tense music continues]
421
00:43:54,798 --> 00:43:56,133
[growling]
422
00:43:56,216 --> 00:43:58,385
- [grunting]
- [growls]
423
00:44:01,764 --> 00:44:04,099
- [growls]
- [wailing]
424
00:44:06,101 --> 00:44:07,102
[roars]
425
00:44:13,859 --> 00:44:16,111
[roars, snarling]
426
00:44:21,784 --> 00:44:23,118
[roars]
427
00:44:26,246 --> 00:44:28,082
- [roaring]
- [grunting]
428
00:44:31,877 --> 00:44:33,879
[dramatic music playing]
429
00:44:35,130 --> 00:44:37,132
- [music fades]
- [wailing]
430
00:44:50,437 --> 00:44:53,232
The rivalry between mammals and reptiles
431
00:44:54,149 --> 00:44:58,862
has been a feature of life on Earth
for hundreds of millions of years.
432
00:45:02,199 --> 00:45:05,452
But their early rise was not to last,
433
00:45:06,286 --> 00:45:09,915
because in the far north of Pangaea,
434
00:45:10,666 --> 00:45:13,460
something catastrophic was happening.
435
00:45:14,712 --> 00:45:16,714
[rumbling]
436
00:45:18,173 --> 00:45:20,592
Lying dormant for years on end,
437
00:45:21,218 --> 00:45:25,222
the colossal forces at work
beneath Earth's surface
438
00:45:26,140 --> 00:45:28,016
are easily forgotten.
439
00:45:33,397 --> 00:45:35,607
But the molten underworld
440
00:45:36,900 --> 00:45:39,194
is always stirring,
441
00:45:40,571 --> 00:45:42,906
always probing for weakness.
442
00:45:44,700 --> 00:45:46,702
[ominous ambient music playing]
443
00:45:48,495 --> 00:45:50,497
[wind whistling]
444
00:45:52,833 --> 00:45:54,835
Beneath Pangaea's crust,
445
00:45:56,128 --> 00:45:58,505
a plume of superheated magma
446
00:45:59,089 --> 00:46:01,467
was working its way to the surface.
447
00:46:08,682 --> 00:46:11,602
Once these Permian eruptions started...
448
00:46:14,521 --> 00:46:16,565
there was no stopping them.
449
00:46:18,233 --> 00:46:20,486
[dramatic music playing]
450
00:46:44,051 --> 00:46:48,430
What made them unique
was their monumental scale.
451
00:46:51,600 --> 00:46:53,602
[dramatic music continues]
452
00:46:58,649 --> 00:47:00,818
They were among the largest,
453
00:47:01,860 --> 00:47:07,032
most violent eruptions
that life has ever witnessed.
454
00:47:17,960 --> 00:47:22,047
And they raged for 100,000 years.
455
00:47:24,091 --> 00:47:27,469
The devastation was unprecedented.
456
00:47:30,305 --> 00:47:33,308
An area half the size
of the United States
457
00:47:34,059 --> 00:47:36,103
lost to lava.
458
00:47:37,062 --> 00:47:39,064
[poignant music playing]
459
00:47:59,001 --> 00:48:01,169
Millions of square kilometers,
460
00:48:01,920 --> 00:48:03,922
once so full of life,
461
00:48:04,506 --> 00:48:07,926
obliterated by the Earth itself.
462
00:48:13,432 --> 00:48:15,434
[music fades]
463
00:48:17,853 --> 00:48:21,481
And that was just the beginning.
464
00:48:25,277 --> 00:48:30,657
The eruptions released something
far more dangerous than lava.
465
00:48:33,911 --> 00:48:38,874
A toxic concoction of noxious gases.
466
00:48:38,957 --> 00:48:40,959
[hissing]
467
00:48:41,043 --> 00:48:43,045
[dramatic music playing]
468
00:48:50,177 --> 00:48:52,888
When these gases combined with water...
469
00:49:00,145 --> 00:49:03,941
a potent cocktail of acid rain
poured down.
470
00:49:13,867 --> 00:49:16,453
Water, the giver of life,
471
00:49:17,412 --> 00:49:20,165
was now its destroyer.
472
00:49:26,880 --> 00:49:29,967
The toxic rain poisoned the ground...
473
00:49:32,094 --> 00:49:33,720
killing off the plants.
474
00:49:41,812 --> 00:49:44,982
Without their roots
to bind the soil together...
475
00:49:49,152 --> 00:49:52,990
entire ecosystems were washed away.
476
00:49:57,452 --> 00:49:59,454
[dramatic music playing]
477
00:49:59,538 --> 00:50:01,540
[rumbling]
478
00:50:01,623 --> 00:50:04,042
[music fades]
479
00:50:12,968 --> 00:50:19,016
And yet, there was something
even more destructive in the air.
480
00:50:22,227 --> 00:50:23,645
A silent killer.
481
00:50:26,815 --> 00:50:29,359
Carbon dioxide.
482
00:50:32,696 --> 00:50:37,242
The volcanoes released six times more CO2
483
00:50:37,868 --> 00:50:40,412
than is in our atmosphere today...
484
00:50:43,457 --> 00:50:46,918
triggering ten degrees of global warming...
485
00:50:47,544 --> 00:50:49,254
[rumbling]
486
00:50:50,797 --> 00:50:53,383
...and all the climate devastation
487
00:50:54,885 --> 00:50:56,386
that comes with it.
488
00:51:01,516 --> 00:51:03,518
[ominous music playing]
489
00:51:03,602 --> 00:51:05,812
[thunder rumbles]
490
00:51:09,691 --> 00:51:15,363
Hothouse Earth raged
as the forces of nature ran wild.
491
00:51:19,076 --> 00:51:21,411
[music intensifies]
492
00:51:40,806 --> 00:51:43,975
There was nowhere to hide from the chaos.
493
00:51:45,727 --> 00:51:49,523
And the oceans were worst affected.
494
00:51:51,983 --> 00:51:54,236
As they warmed and acidified,
495
00:51:55,112 --> 00:51:57,114
oxygen levels plummeted...
496
00:51:59,699 --> 00:52:03,787
turning the seas,
where life first took hold,
497
00:52:06,039 --> 00:52:08,208
into a desolate graveyard.
498
00:52:11,378 --> 00:52:14,005
This was the planet's third,
499
00:52:14,673 --> 00:52:18,218
and most devastating, mass extinction.
500
00:52:18,301 --> 00:52:20,178
[melancholy music playing]
501
00:52:20,262 --> 00:52:23,557
Ninety percent of all species
502
00:52:24,474 --> 00:52:26,852
lost forever.
503
00:52:33,024 --> 00:52:37,737
Entire branches torn off
the evolutionary tree.
504
00:52:46,288 --> 00:52:47,747
But in the loss of many,
505
00:52:48,748 --> 00:52:50,417
endured the few.
506
00:52:51,334 --> 00:52:52,794
[rustling]
507
00:52:56,506 --> 00:52:58,884
[breathing heavily]
508
00:52:58,967 --> 00:53:02,179
All that remained of a bygone age.
509
00:53:07,392 --> 00:53:13,064
Never had their survival
been so important.
510
00:53:17,527 --> 00:53:20,488
The future of all life
511
00:53:21,573 --> 00:53:24,534
now hung by a thread.
512
00:53:24,618 --> 00:53:26,995
[ethereal music playing]
513
00:53:32,584 --> 00:53:34,544
[music continues]