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National Geographic
Earth: Making of a Planet
Original Air Date on March 6, 2011
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-- sync, corrected by elderman --
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The Earth, as
far as we know it's the
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only home to life
in the universe.
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So what makes our
planet so special?
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To find answers, we
must travel back in time.
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See the first humans
walk the Earth.
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Ride each colliding
continent.
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Face killer dinosaurs.
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Dive into oceans full
of bizarre life forms.
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Feel the bitter chill
of global ice ages.
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And experience the fury of
cosmic missile attacks.
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By travelling
back in time,
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we can piece together
our planet's incredible
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story.
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And discover why all of
this, and all of us,
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are here.
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The journey starts
almost five billion
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years ago.
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There's no sign of
Earth just yet.
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Only the Sun, a newborn
star surrounded by dust.
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The Earth hasn't
formed yet.
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But through time,
gravity pulls the dust
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into tiny rocks.
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To our surprise,
something as complex as
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a planet is made from
nothing more than dust
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and rocks.
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Over millions of years,
gravity pulls these
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rocks together to
form the Earth,
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one of at least a
hundred planets
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circling the sun.
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But four and a half
billion years ago,
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Earth looks more
like hell than home.
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Up close the
temperature is over
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2,000 degrees
Fahrenheit.
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There's no air, just
carbon dioxide,
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nitrogen
and water vapor.
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It's so hot and toxic
that if we got any
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closer we'd be
incinerated and
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suffocated in seconds.
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This newborn planet
is a boiling ball of
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liquid rock;
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an endless ocean of lava.
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A young planet called
Theia is heading
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straight for Earth.
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The size of Mars, it
travels nearly 10 miles
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per second, twenty
times faster than a
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bullet.
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The intruder's gravity
distorts the Earth's surface.
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The blast wave races
around the planet.
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It's as though both young
planets turn to liquid,
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trillions of
tons of debris blast
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out into space.
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But over the course
of a thousand years,
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gravity turns the
rubble into a ring of
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red hot dust and rock
that circles the Earth.
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From this ring,
a ball forms,
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over two thousand
miles wide.
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It's the birth
of our moon.
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But it's much closer
than the moon today,
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just 14,000 miles away
instead of a quarter of
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a million miles.
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The sun rises over
a cooling Earth.
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And sets just
three hours later.
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The Earth is spinning
so fast that an entire
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day lasts six hours.
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The days may pass
quickly but the Earth
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changes slowly.
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To understand the
making of our planet we
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need to fast foard
through millions of years.
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3.9 billion
years ago,
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a hail of meteors
attack the Earth.
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It's debris left over
from the solar system's
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formation.
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Inside the meteors are
crystals that look like
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grains of salt.
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And inside the crystals
are minute droplets of
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water.
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These deadly missiles
could contain the vital
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ingredient for
life on Earth.
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Only a small amount of
water exists inside
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each meteorite, but as
they bombard the Earth
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for over 20
million years,
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pools of water grow.
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The Earth's core
remains molten,
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but its surface has
cooled enough to form a
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crust.
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The air is around
170 degrees.
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In the future, there's
a chance we could
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swallow
this very water.
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Every sip,
every puddle,
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every drop of water
in every ocean,
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is billions
of years old.
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00:09:53,836 --> 00:09:55,703
And it may have
travelled millions of
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miles to reach us,
carried inside a
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meteor.
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The Earth looks
more familiar,
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but it's still a
dangerous place.
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Winds are faster than
the most destructive
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hurricanes today.
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It's a mega storm,
whipped up by the
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planet's rapid
rotation.
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The moon is so close to
Earth that its gravity
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is overwhelmed,
creating huge tides
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that race across the
planet's surface.
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00:11:13,882 --> 00:11:16,684
But over time, the
moon moves away,
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the waves calm down
and the planet spins slower.
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700 million years after
the planet's birth,
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life-giving water
covers its surface.
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And scattered
throughout are tiny
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islands.
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00:11:45,514 --> 00:11:49,951
They seem to have
appeared from nowhere.
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00:11:51,854 --> 00:11:55,823
So how did
they get here?
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Molten rock bursts
through the Earth's
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crust and rises up
through the ocean.
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Over time the
lava cools,
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forming a
volcanic island.
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In the future, these
islands will join
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together to form the
first continents.
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Earth now has
water and land.
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It's beginning to look like
the planet we call home.
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But the atmosphere is
still toxic and the
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temperature
is scorching.
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Life here is
impossible.
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00:12:55,691 --> 00:12:57,759
Since the
planet's formation,
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meteors have been
pummeling Earth.
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00:13:02,365 --> 00:13:06,668
But now, 3.8
billion years ago,
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00:13:06,735 --> 00:13:09,904
the assault enters a
violent new phase.
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00:13:09,972 --> 00:13:12,039
Something's disturbed
the orbits of these
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meteorites.
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00:13:18,078 --> 00:13:20,313
In addition to water,
the meteors carry
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something else.
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As they dissolve, the
meteorites release
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minerals.
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Carbon and primitive
proteins made of amino
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acids are transported
from outer space to the
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00:13:42,468 --> 00:13:45,336
bottom of the ocean.
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00:13:50,475 --> 00:13:54,211
Thousands of feet below
the waves, it is dark,
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00:13:54,278 --> 00:13:57,947
and close to freezing.
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00:14:13,031 --> 00:14:17,768
But a dramatic illusion
is taking shape.
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00:14:19,438 --> 00:14:25,010
Underwater chimneys,
spewing hot liquid.
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Seawater seeps down
into the Earth through
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cracks in the crust,
collecting minerals and
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gases along the way.
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00:14:36,656 --> 00:14:39,323
This potent mixture is
released back out into
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00:14:39,391 --> 00:14:44,027
the ocean, building
these towers.
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00:14:48,399 --> 00:14:50,067
Combined with the
minerals and chemicals
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from the meteorites,
the water becom a
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00:14:52,670 --> 00:14:54,804
chemical soup.
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00:14:57,008 --> 00:14:59,843
It's impossible to
know how or when,
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00:14:59,911 --> 00:15:02,279
but somehow these
chemicals come together
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to create life.
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00:15:07,519 --> 00:15:09,521
The water is now
full of microscopic
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organisms.
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00:15:11,357 --> 00:15:13,859
These single-celled
bacteria are the
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earliest forms
of life on Earth.
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This is a defining
moment in the making of
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the planet.
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Microscopic life
is underway.
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For hundreds of
millions of years
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nothing changes.
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The only life is
single-celled bacteria.
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00:16:04,347 --> 00:16:06,482
To find more
complex life,
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00:16:06,550 --> 00:16:11,720
we need to fast forward
to 3.5 billion years ago,
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00:16:15,158 --> 00:16:18,961
and a
shallow ocean.
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These look like rocks,
or even plants,
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growing out of
the sea bed.
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Each mound is a colony
of living bacteria
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called a stromatolite.
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00:16:45,322 --> 00:16:48,590
These bacteria turn
sunlight into food,
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a process called
photosynthesis.
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00:16:51,961 --> 00:16:54,829
It uses the power of
sunlight to traform
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carbon dioxide and
water into glucose,
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a simple form of sugar.
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00:17:15,386 --> 00:17:18,688
And this magical
transformation releases
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a by-product, a
gas called oxygen.
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Underwater, the
stromatolites slowly
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00:17:30,102 --> 00:17:34,171
fill the oceans
with oxygen.
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00:17:37,442 --> 00:17:40,643
The oxygen then turns
traces of iron into
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00:17:40,711 --> 00:17:43,846
rust, which fall
to the ocean floor,
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00:17:43,914 --> 00:17:47,717
to form deposits
of iron rich rock.
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00:17:47,785 --> 00:17:50,220
It's this mineral that
will one day be used to
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build bridges, ships,
and skyscrapers.
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00:18:05,439 --> 00:18:08,374
Above the waves, the
oxygen transforms the
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00:18:08,442 --> 00:18:10,577
atmosphere.
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00:18:10,644 --> 00:18:12,812
These stromatolites
are creating the most
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00:18:12,880 --> 00:18:16,883
important element
for life on earth.
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00:18:16,950 --> 00:18:19,853
Without them, virtually
every living thing
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wouldn't exist.
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00:18:30,265 --> 00:18:32,600
Over the next two
billion years oxygen
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levels continue
to rise,
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00:18:35,271 --> 00:18:37,740
and as the planet's
spin slows,
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the days get longer,
lasting at least 16 hours.
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3 billion years after
the planet's birth,
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00:18:56,792 --> 00:18:59,160
there's still no
complex life,
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00:18:59,228 --> 00:19:05,466
no plants, no
dinosaurs, no humans.
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00:19:06,234 --> 00:19:08,669
But the Earth has
something unlike any
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00:19:08,737 --> 00:19:11,439
other planet in
this solar system,
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a force with the power
to change everything.
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00:19:23,316 --> 00:19:24,650
One and
a half billion
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years ago, the Earth is
a beautiful blue ball,
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dotted with
volcanic islands.
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00:19:33,827 --> 00:19:37,063
Over millions of years,
a mysterious force
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00:19:37,131 --> 00:19:40,099
rearranges
these islands.
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00:19:40,167 --> 00:19:41,700
Hidden beneath
the ocean,
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00:19:41,768 --> 00:19:44,369
the Earth's crust
breaks into vast
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plates.
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00:19:46,706 --> 00:19:50,574
But even deeper, the
Earth's core is so hot
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00:19:50,642 --> 00:19:52,977
that it generates
movement in the rock
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00:19:53,044 --> 00:19:56,646
beneath the crust.
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00:19:57,014 --> 00:19:59,482
These movements push
and pull the plates
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00:19:59,550 --> 00:20:02,886
around the globe,
carrying the oceans and
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00:20:02,954 --> 00:20:05,856
islands with them.
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00:20:06,625 --> 00:20:09,827
Millions of
years race by,
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00:20:09,895 --> 00:20:14,065
our planet is alive,
and changing.
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00:20:15,968 --> 00:20:19,169
Over 400 million years
a vast new super
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00:20:19,237 --> 00:20:21,372
continent takes shape.
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00:20:21,439 --> 00:20:25,543
It's called Rodinia.
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00:20:29,748 --> 00:20:32,583
In the shallow waters
surrounding Rodinia,
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00:20:32,651 --> 00:20:34,852
stromatolites work
their magic for more
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00:20:34,920 --> 00:20:38,789
than two billion years,
pumping oxygen into the
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00:20:38,857 --> 00:20:40,957
atmosphere.
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00:20:42,127 --> 00:20:45,195
The temperature
is 85 degrees.
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00:20:45,530 --> 00:20:49,467
And the days are
18 hours long.
225
00:20:56,842 --> 00:21:00,379
But this planet looks
more like Mars than Earth.
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00:21:05,552 --> 00:21:09,056
To find life, we must
fast forward through time.
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00:21:21,968 --> 00:21:27,772
Washington State: 750
million years ago.
228
00:21:27,840 --> 00:21:30,909
A force deep inside the
planet rips the crust
229
00:21:30,976 --> 00:21:33,310
to pieces.
230
00:21:33,378 --> 00:21:34,879
It's as though the
world is breaking
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00:21:34,946 --> 00:21:36,847
apart.
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00:21:38,517 --> 00:21:40,218
And there's only one
force powerful enough
233
00:21:40,285 --> 00:21:44,389
to do this, heat.
234
00:21:45,157 --> 00:21:47,926
It escapes from the
Earth's molten core,
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00:21:47,993 --> 00:21:52,463
stretching and
weakening the crust.
236
00:21:52,531 --> 00:21:55,566
Inch by inch,
year by year,
237
00:21:55,634 --> 00:21:56,867
the great
super-continent is
238
00:21:56,935 --> 00:22:00,671
splitting in two.
239
00:22:38,046 --> 00:22:41,014
The intense geological
activity spawns a mass
240
00:22:41,082 --> 00:22:43,417
of volcanoes.
241
00:22:43,685 --> 00:22:45,185
They pump carbon
dioxide into the
242
00:22:45,253 --> 00:22:47,988
atmosphere.
243
00:23:04,741 --> 00:23:07,176
The carbon dioxide
mixes with water,
244
00:23:07,244 --> 00:23:10,746
and creates acid rain.
245
00:23:20,957 --> 00:23:23,024
When the continent
tore apart,
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00:23:23,092 --> 00:23:29,063
many rocks
were exposed.
247
00:23:29,665 --> 00:23:32,800
These rocks absorb
the acid rain,
248
00:23:32,868 --> 00:23:35,536
including its
carbon dioxide.
249
00:23:35,604 --> 00:23:38,806
Vast quantities of CO 2
are absorbed out of the
250
00:23:38,874 --> 00:23:41,309
atmosphere.
251
00:23:48,585 --> 00:23:51,221
Now, there's not enough
carbon dioxide in the
252
00:23:51,288 --> 00:23:56,426
air to trap the sun's
heat around the planet.
253
00:23:57,061 --> 00:23:59,129
In just a few
thousand years,
254
00:23:59,197 --> 00:24:01,565
the temperature
plummets to around
255
00:24:01,632 --> 00:24:05,601
minus 60 degrees.
256
00:24:05,836 --> 00:24:08,837
This frozen wasteland
is Southern Australia,
257
00:24:08,905 --> 00:24:13,675
650 million years ago.
258
00:24:13,743 --> 00:24:16,978
It's the start of what
some scientists call
259
00:24:17,046 --> 00:24:20,682
Snowball Earth, a
period they believe to
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00:24:20,750 --> 00:24:24,353
be the longest, coldest
ice age ever to grip
261
00:24:24,421 --> 00:24:25,321
the planet.
262
00:24:30,495 --> 00:24:33,397
A vast wall of ice
looms thousands of feet
263
00:24:33,465 --> 00:24:35,066
high.
264
00:24:37,002 --> 00:24:40,805
And it's unstoppable.
265
00:24:41,073 --> 00:24:43,541
The more ice there is
the more sunlight it
266
00:24:43,608 --> 00:24:45,776
reflects away
from the planet,
267
00:24:45,844 --> 00:24:49,579
and the faster
the ice spreads.
268
00:24:50,447 --> 00:24:55,617
Nearby is a second ice
sheet just as high.
269
00:24:55,685 --> 00:24:58,220
The two sheets spread
away from the poles,
270
00:24:58,288 --> 00:25:00,789
toward each other to
meet at the Equator.
271
00:25:24,714 --> 00:25:27,082
Now an ice
sheet up to 10,000
272
00:25:27,150 --> 00:25:33,056
feet thick covers
the entire planet.
273
00:25:34,525 --> 00:25:38,295
Earth first began as a
molten ball of fire,
274
00:25:38,363 --> 00:25:42,499
now it's a frozen
ball of ice.
275
00:25:45,970 --> 00:25:49,073
Virtually all the sun's
light, and warmth,
276
00:25:49,140 --> 00:25:54,245
reflects back
into space.
277
00:26:01,320 --> 00:26:03,221
And it seems as
though nothing,
278
00:26:03,289 --> 00:26:06,625
not even the Sun can
rescue the planet now.
279
00:26:19,393 --> 00:26:22,094
650
million years ago,
280
00:26:22,162 --> 00:26:25,432
ice entombs the planet.
281
00:26:25,499 --> 00:26:28,302
For 15 million years,
the Earth is a vast
282
00:26:28,369 --> 00:26:31,171
frozen snowball.
283
00:26:33,275 --> 00:26:35,243
But it can't
last forever;
284
00:26:35,311 --> 00:26:37,646
something must release
the Earth from this
285
00:26:37,713 --> 00:26:41,250
frozen prison.
286
00:26:41,318 --> 00:26:43,653
And when it does, who
knows whether life has
287
00:26:43,720 --> 00:26:46,956
survived
beneath the ice.
288
00:26:47,024 --> 00:26:49,993
The surface is frozen
but the core is still
289
00:26:50,060 --> 00:26:53,962
hotter than the
sun's surface.
290
00:26:59,568 --> 00:27:01,235
Volcanoes have been
erupting since the
291
00:27:01,302 --> 00:27:03,837
world began to freeze.
292
00:27:03,905 --> 00:27:07,373
But up until now even
their heat and power
293
00:27:07,441 --> 00:27:11,344
made no impact
on the ice.
294
00:27:13,648 --> 00:27:16,016
Volcanoes pump out
billions of tons of
295
00:27:16,084 --> 00:27:19,687
carbon dioxide.
296
00:27:19,954 --> 00:27:22,590
Before the big freeze,
the Earth's rocks
297
00:27:22,657 --> 00:27:27,195
absorbed most
of the CO2.
298
00:27:27,530 --> 00:27:30,632
But now, with the rocks
smothered in ice,
299
00:27:30,700 --> 00:27:33,168
there's nothing to
absorb the gas.
300
00:27:33,236 --> 00:27:36,639
So it fills the
atmosphere.
301
00:27:43,447 --> 00:27:46,149
Like a blanket, it
traps the sun's warmth
302
00:27:46,217 --> 00:27:47,884
around the planet,
allowing the
303
00:27:47,952 --> 00:27:51,921
temperatures to rise.
304
00:27:52,223 --> 00:27:55,725
Now, after 15
million years,
305
00:27:55,793 --> 00:27:58,861
the ice begins to melt.
306
00:28:21,321 --> 00:28:23,822
It's thought that
during Snowball Earth
307
00:28:23,890 --> 00:28:26,524
the ice pushed
the crust down.
308
00:28:26,592 --> 00:28:31,029
But now, as it melts,
the crust bounces up,
309
00:28:31,097 --> 00:28:35,099
creating fissures
and weak spots,
310
00:28:35,167 --> 00:28:37,769
and more volcanoes.
311
00:28:42,742 --> 00:28:45,844
The volcanoes release
more carbon dioxide and
312
00:28:45,912 --> 00:28:50,049
push the temperature
up even higher.
313
00:28:50,450 --> 00:28:54,887
The melt gathers
momentum.
314
00:28:54,955 --> 00:28:58,859
And oxygen levels rise.
315
00:28:59,628 --> 00:29:02,363
Through a series of
chemical reactions the
316
00:29:02,431 --> 00:29:05,867
ice has created oxygen.
317
00:29:06,168 --> 00:29:08,002
While the planet
was frozen,
318
00:29:08,070 --> 00:29:11,439
the Sun's ultraviolet
rays reacted with water
319
00:29:11,506 --> 00:29:14,709
molecules in the ice,
to produce hydrogen
320
00:29:14,777 --> 00:29:18,679
peroxide, a chemical
rich in oxygen.
321
00:29:30,726 --> 00:29:34,262
Now, as the ice melts,
the hydrogen peroxide
322
00:29:34,330 --> 00:29:36,398
breaks down and
releases massive
323
00:29:36,465 --> 00:29:41,102
amounts of oxygen.
324
00:29:47,176 --> 00:29:51,046
The Earth is waking
up, and it's a very
325
00:29:51,114 --> 00:29:53,215
different place.
326
00:30:30,985 --> 00:30:33,919
600 million years ago,
the atmosphere is
327
00:30:33,987 --> 00:30:37,857
warmer, like
a summer day.
328
00:30:39,926 --> 00:30:45,163
And the days are
about 22 hours long.
329
00:30:50,203 --> 00:30:54,140
Add all this water and
it's the perfect recipe
330
00:30:54,208 --> 00:30:56,142
for life.
331
00:31:00,448 --> 00:31:03,050
Before Snowball Earth,
primitive bacteria
332
00:31:03,118 --> 00:31:06,387
emerged in the oceans.
333
00:31:06,455 --> 00:31:08,623
But surely they
couldn't have survived
334
00:31:08,691 --> 00:31:12,593
an ice age 75 times
longer than the entire
335
00:31:12,661 --> 00:31:15,995
span of human history.
336
00:31:16,197 --> 00:31:18,131
If something
has survived,
337
00:31:18,198 --> 00:31:21,600
then life may be found
where it was last seen,
338
00:31:21,668 --> 00:31:24,069
in the oceans.
339
00:31:28,308 --> 00:31:31,677
Now, 540 million
years ago,
340
00:31:31,745 --> 00:31:33,913
in an ocean
full of oxygen,
341
00:31:33,981 --> 00:31:38,551
those primitive
bacteria have evolved.
342
00:31:38,853 --> 00:31:40,387
A handful must have
clung on through the
343
00:31:40,455 --> 00:31:43,490
big freeze.
344
00:31:43,557 --> 00:31:45,192
There are plants
scattered on the sea
345
00:31:45,260 --> 00:31:49,663
floor.
346
00:31:49,998 --> 00:31:54,868
And something else.
347
00:31:55,103 --> 00:31:57,771
What looks like an
armored slug takes up
348
00:31:57,839 --> 00:31:59,873
residence.
349
00:31:59,941 --> 00:32:04,077
It's called Wiwaxia,
a new generation of
350
00:32:04,145 --> 00:32:08,781
complex multi-celled
organisms.
351
00:32:09,016 --> 00:32:10,617
The Earth enters one
of the most dynamic
352
00:32:10,685 --> 00:32:17,691
periods in its history,
the Cambrian explosion.
353
00:32:17,758 --> 00:32:20,460
Increased oxygen levels
allow creatures to grow
354
00:32:20,528 --> 00:32:26,867
larger and develop
bony skeletons.
355
00:32:27,035 --> 00:32:33,840
There are
worms, sponges,
356
00:32:33,908 --> 00:32:37,810
and these trilobites:
distant relatives of
357
00:32:37,878 --> 00:32:42,681
insects, lobsters,
even scorpions.
358
00:32:51,090 --> 00:32:55,760
Life in the
oceans blossoms.
359
00:32:56,696 --> 00:33:02,834
From microscopic
bacteria, to monsters.
360
00:33:12,410 --> 00:33:15,946
This is Anomalocaris.
361
00:33:16,013 --> 00:33:20,850
Nearly two feet long,
it has large eyes,
362
00:33:20,918 --> 00:33:25,588
razor sharp teeth
and grasping limbs.
363
00:33:43,409 --> 00:33:48,046
All it has to do,
is take its pick.
364
00:33:56,322 --> 00:33:58,556
The trilobite can't
right itself,
365
00:33:58,624 --> 00:34:02,861
its soft belly
is exposed.
366
00:34:16,978 --> 00:34:19,813
Also found in the
sea is Pikaia.
367
00:34:19,881 --> 00:34:22,116
Only an inch
and a half long,
368
00:34:22,183 --> 00:34:27,621
they may be the first
organism with a spine.
369
00:34:31,559 --> 00:34:34,795
Over millions of years,
this simple structure
370
00:34:34,863 --> 00:34:37,965
will evolve into the
spine that keeps us
371
00:34:38,033 --> 00:34:40,468
standing.
372
00:34:57,319 --> 00:34:59,854
Expecting to find
life in ruins,
373
00:34:59,922 --> 00:35:05,093
the oceans are in
fact full of life.
374
00:35:06,028 --> 00:35:09,797
Where trilobites
scavenge and monsters
375
00:35:09,865 --> 00:35:12,366
prowl.
376
00:35:12,434 --> 00:35:14,235
And where creatures
begin to take on
377
00:35:14,302 --> 00:35:16,537
familiar forms.
378
00:35:19,441 --> 00:35:22,376
Beneath the waves there
are already tens of
379
00:35:22,444 --> 00:35:27,314
thousands of plant
and animal species.
380
00:35:27,382 --> 00:35:30,718
The advance of life
seems unstoppable.
381
00:35:47,265 --> 00:35:49,867
460
million years ago,
382
00:35:49,934 --> 00:35:53,537
the plates have
been moving, again.
383
00:35:53,772 --> 00:35:59,143
A new continent now
exists, Gondwana.
384
00:36:00,979 --> 00:36:03,648
It's 90 degrees and
oxygen levels are close
385
00:36:03,715 --> 00:36:06,684
to what they are today.
386
00:36:08,587 --> 00:36:10,888
The land should be
covered with plants and
387
00:36:10,955 --> 00:36:13,557
crawling with
creatures.
388
00:36:13,625 --> 00:36:15,592
But there's
not much here,
389
00:36:15,660 --> 00:36:18,796
besides a few
patches of algae.
390
00:36:27,238 --> 00:36:36,146
There's only one
explanation, the Sun.
391
00:36:40,085 --> 00:36:46,391
It blasts the surface
with deadly radiation,
392
00:36:46,459 --> 00:36:48,494
so the complex life in
the ocean doesn't stand
393
00:36:48,562 --> 00:36:50,796
a chance on land.
394
00:36:54,668 --> 00:36:57,136
But 30 miles up, where
the rays enter the
395
00:36:57,204 --> 00:37:02,074
Earth's atmosphere,
something is happening.
396
00:37:04,177 --> 00:37:06,813
When oxygen meets
the sun's radiation,
397
00:37:06,880 --> 00:37:09,081
it turns into
another kind of gas,
398
00:37:09,149 --> 00:37:11,951
call ozone.
399
00:37:13,754 --> 00:37:15,689
This gas forms a
blanket around the
400
00:37:15,756 --> 00:37:19,392
planet and absorbs
the lethal radiation.
401
00:37:22,163 --> 00:37:25,699
Over 120 million years,
the ozone layer gets
402
00:37:25,767 --> 00:37:28,936
thicker and prevents
more and more radiation
403
00:37:29,003 --> 00:37:32,105
from reaching the
Earth's surface.
404
00:37:32,173 --> 00:37:34,942
Without this layer,
life on land simply
405
00:37:35,009 --> 00:37:37,110
wouldn't exist.
406
00:37:37,511 --> 00:37:39,946
Now, shielded
from radiation,
407
00:37:40,013 --> 00:37:43,082
life takes off.
408
00:37:46,519 --> 00:37:52,224
Small mossy lumps are
the first land plants.
409
00:37:52,759 --> 00:37:56,261
They pump out
even more oxygen.
410
00:37:56,329 --> 00:38:00,766
Levels soar.
411
00:38:06,941 --> 00:38:11,011
375 million years ago,
a new species lives in
412
00:38:11,079 --> 00:38:14,648
the water, swimming.
413
00:38:26,395 --> 00:38:31,566
It's a strange fish
called a Tiktaalik.
414
00:38:53,622 --> 00:38:58,192
It uses its neck to
raise itself up.
415
00:39:12,374 --> 00:39:14,442
And its fins
function as legs,
416
00:39:18,780 --> 00:39:22,049
allowing it to move
out of the water.
417
00:39:34,063 --> 00:39:36,598
This is one of the most
important moments in
418
00:39:36,666 --> 00:39:39,567
the making of
our planet.
419
00:39:40,269 --> 00:39:43,605
Over 15 million years,
creatures like these
420
00:39:43,673 --> 00:39:45,374
evolve.
421
00:39:46,843 --> 00:39:49,145
They grow stronger
limbs and spend more
422
00:39:49,213 --> 00:39:52,214
time out of the water,
where plant life is
423
00:39:52,282 --> 00:39:54,650
exploding.
424
00:39:55,018 --> 00:39:58,587
Until, 360 million
years ago,
425
00:39:58,655 --> 00:40:01,456
their relatives,
called tetrapods,
426
00:40:01,524 --> 00:40:04,660
make the land
their home.
427
00:40:04,828 --> 00:40:07,429
From tetrapods, four
legged vertebrates
428
00:40:07,497 --> 00:40:10,399
evolve into
dinosaurs, birds,
429
00:40:10,467 --> 00:40:15,504
mammals and
eventually humans.
430
00:40:18,875 --> 00:40:22,011
There are mosses and
ferns everywhere,
431
00:40:22,079 --> 00:40:26,582
some at least a
hundred feet tall.
432
00:40:26,984 --> 00:40:29,285
A seed is carried
by the wind.
433
00:40:35,326 --> 00:40:36,626
Until now,
434
00:40:36,694 --> 00:40:39,395
plants reproduced
using spores,
435
00:40:39,463 --> 00:40:41,831
single-celled particles
that need plenty of
436
00:40:41,899 --> 00:40:44,800
water to grow.
437
00:40:46,236 --> 00:40:50,339
But this seed is
miles from water.
438
00:40:52,776 --> 00:40:55,344
This embryonic plant
has its own food and
439
00:40:55,411 --> 00:40:58,780
water supply.
440
00:40:58,848 --> 00:41:02,083
Unlike a spore, this
seed can survive far
441
00:41:02,151 --> 00:41:06,620
from water for
months, even years.
442
00:41:19,165 --> 00:41:22,501
The humble seed spreads
life across the planet.
443
00:41:22,569 --> 00:41:25,437
And each tree and plant
pumps out even more
444
00:41:25,505 --> 00:41:27,706
oxygen.
445
00:41:41,589 --> 00:41:45,692
It's an environment
very much like today.
446
00:42:02,675 --> 00:42:05,343
The planet has
come a long way,
447
00:42:05,411 --> 00:42:08,479
from a lump of burning
rock and dust,
448
00:42:08,547 --> 00:42:11,315
to a blue and green
world bursting with
449
00:42:11,382 --> 00:42:13,017
life.
450
00:42:19,023 --> 00:42:27,598
There are now fish,
plants, and this,
451
00:42:29,301 --> 00:42:31,402
the dragonfly.
452
00:42:34,272 --> 00:42:37,008
It's called Meganeura.
453
00:42:37,710 --> 00:42:41,812
This insect is the
size of an eagle.
454
00:42:41,879 --> 00:42:43,948
What were once legs
have evolved into
455
00:42:44,015 --> 00:42:47,051
wings, extending the
dragonfly's hunting
456
00:42:47,119 --> 00:42:51,089
territory over
a vast area.
457
00:42:54,860 --> 00:42:56,894
There are also
millipedes,
458
00:42:56,962 --> 00:43:00,732
and spiders down there.
459
00:43:04,937 --> 00:43:08,173
These creatures,
called arthropod,
460
00:43:08,240 --> 00:43:10,541
were among the first
to set foot on land
461
00:43:10,609 --> 00:43:13,277
hundreds of millions
of years ago.
462
00:43:13,612 --> 00:43:16,080
They look almost
identical to the bugs
463
00:43:16,148 --> 00:43:18,883
that invade our
homes today.
464
00:43:18,951 --> 00:43:21,418
Except for one
big difference.
465
00:43:21,486 --> 00:43:25,823
Like the Meganeura,
they're monsters.
466
00:43:25,991 --> 00:43:28,058
It's a world
full of giants,
467
00:43:28,126 --> 00:43:31,028
where millipedes
are 6 feet long,
468
00:43:31,095 --> 00:43:36,867
andcorpions are
the size of wolves.
469
00:43:38,336 --> 00:43:40,637
This is because the
oxygen level is much
470
00:43:40,705 --> 00:43:42,705
higher than it is
today,
471
00:43:42,773 --> 00:43:45,041
which allows their
respiratory systems to
472
00:43:45,108 --> 00:43:47,676
be more efficient,
fueling thier bodies to
473
00:43:47,744 --> 00:43:50,179
grow larger.
474
00:43:59,788 --> 00:44:02,256
So far, animals have
been laying their eggs
475
00:44:02,324 --> 00:44:05,993
in the water.
476
00:44:06,194 --> 00:44:07,928
But a lizard-like
creature,
477
00:44:07,996 --> 00:44:11,832
called the hylonomus,
prefers land.
478
00:44:12,601 --> 00:44:15,737
Its eggs contain all
the water and nutrients
479
00:44:15,804 --> 00:44:18,973
that the developing
fetus needs.
480
00:44:19,041 --> 00:44:20,342
The babies grow
in their own
481
00:44:20,409 --> 00:44:23,011
self-contained pond.
482
00:44:23,079 --> 00:44:25,147
The egg is a major
evolutionary
483
00:44:25,215 --> 00:44:27,517
breakthrough.
484
00:44:28,252 --> 00:44:31,387
Allowing animals to
leave the water behind,
485
00:44:31,455 --> 00:44:34,190
and conquer land.
486
00:44:46,168 --> 00:44:51,305
This baby hylonomus
leads the advance,
487
00:44:52,807 --> 00:44:56,577
as a new creature,
the reptile.
488
00:45:10,493 --> 00:45:14,997
Inevitably, with
life, comes death.
489
00:45:15,598 --> 00:45:18,233
Dead plant matter
builds up and decays
490
00:45:18,301 --> 00:45:22,370
into dense
soggy layers.
491
00:45:22,438 --> 00:45:24,072
Over hundreds of
millions of years,
492
00:45:24,140 --> 00:45:26,441
rocks cover
these layers.
493
00:45:26,508 --> 00:45:27,942
And heat from the
Earth's core and
494
00:45:28,010 --> 00:45:30,144
pressure from the
overlying rocks
495
00:45:30,212 --> 00:45:34,783
transform these layers
into seams of coal.
496
00:45:36,385 --> 00:45:39,221
Each lump of coal
burned today is made of
497
00:45:39,289 --> 00:45:44,294
plants that died 300
million years ago.
498
00:45:55,774 --> 00:45:58,475
Amidst the decay,
hidden from sight,
499
00:45:58,542 --> 00:46:01,077
life is stirring.
500
00:46:01,412 --> 00:46:03,713
Soon seeds will
germinate,
501
00:46:03,781 --> 00:46:06,349
plants will grow, and
this wasteland will
502
00:46:06,417 --> 00:46:08,552
live again.
503
00:46:08,620 --> 00:46:12,322
Life seems to have
conquered the planet.
504
00:46:12,389 --> 00:46:13,823
But will it last?
505
00:46:29,703 --> 00:46:31,304
A herd of
creatures graze
506
00:46:31,371 --> 00:46:37,743
the Siberian plains,
and they are big.
507
00:46:44,952 --> 00:46:48,521
Evolution takes a
huge leap forward,
508
00:46:48,589 --> 00:46:53,426
small lizards are
now giant reptiles.
509
00:46:54,061 --> 00:46:57,630
These scutosaurs are
distant relatives of
510
00:46:57,698 --> 00:47:01,234
turtles.
511
00:47:03,871 --> 00:47:06,806
If these plant eaters
look this tough,
512
00:47:06,873 --> 00:47:11,777
the carnivores must
be seriously mean.
513
00:47:15,849 --> 00:47:19,184
Like this gorgonopsid.
514
00:47:19,252 --> 00:47:21,754
A perfectly engineered
pre-historic killing
515
00:47:21,821 --> 00:47:23,389
machine.
516
00:47:41,677 --> 00:47:44,579
The gorgonopsid's sabre-teeth
wound the scutosaur.
517
00:47:56,457 --> 00:47:58,124
The predator watches,
518
00:47:58,192 --> 00:48:01,661
as its prey grows
weak from blood loss.
519
00:48:03,264 --> 00:48:09,570
But before it can
make its final move,
520
00:48:09,638 --> 00:48:12,841
something
strange happens.
521
00:48:12,908 --> 00:48:17,046
The ground gets hot.
522
00:48:22,787 --> 00:48:25,488
Enormous pressure builds
beneath the surface,
523
00:48:25,556 --> 00:48:28,524
and lava spews
into the air.
524
00:48:57,858 --> 00:49:01,861
But the lava isn't from
one single volcano,
525
00:49:01,929 --> 00:49:05,264
the entire landscape
is erupting.
526
00:49:07,467 --> 00:49:09,868
It's a flood
basalt eruption.
527
00:49:09,936 --> 00:49:12,704
A massive plume of
mantle rises up from
528
00:49:12,772 --> 00:49:16,007
deep inside the Earth,
and pushes molten rock
529
00:49:16,074 --> 00:49:21,812
out through fissures
in the Earth's crust.
530
00:49:24,249 --> 00:49:28,152
The lush paradise is
now a lifeless hell.
531
00:49:28,220 --> 00:49:33,125
The scutosaurs and the
gorgonopsids are dead.
532
00:49:33,560 --> 00:49:35,561
They're the first
casualties in the
533
00:49:35,629 --> 00:49:37,830
greatest mass
extinction the world
534
00:49:37,898 --> 00:49:42,603
has ever seen, the
Permian Extinction.
535
00:49:53,480 --> 00:49:56,215
On the other side of
the continent Gondwana,
536
00:49:56,282 --> 00:50:00,885
nothing's changed, yet.
537
00:50:09,796 --> 00:50:11,997
It appears to
be snowing,
538
00:50:12,065 --> 00:50:17,169
but the temperature
is about 70 degrees.
539
00:50:17,237 --> 00:50:19,372
It's actually ash,
fallout from the
540
00:50:19,440 --> 00:50:23,543
eruptions some
10,000 miles away.
541
00:50:28,384 --> 00:50:31,185
The ash burns and
suffocates the animals,
542
00:50:31,253 --> 00:50:34,055
killing them
around the world.
543
00:50:45,934 --> 00:50:48,769
Sulphur dioxide from
the eruptions fills the
544
00:50:48,837 --> 00:50:51,505
atmosphere.
545
00:50:52,040 --> 00:50:55,141
As it rains, the gas
turns to sulphuric
546
00:50:55,209 --> 00:50:59,211
acid, and burns
everything it falls on.
547
00:51:02,917 --> 00:51:06,486
What was a local
disaster has now turned
548
00:51:06,554 --> 00:51:08,355
global.
549
00:51:20,570 --> 00:51:22,972
The Siberian eruptions
increase the Earth's
550
00:51:23,040 --> 00:51:26,042
carbon dioxide levels.
551
00:51:26,110 --> 00:51:28,878
The atmosphere
gets hotter.
552
00:51:28,946 --> 00:51:32,849
Water evaporates.
553
00:51:32,917 --> 00:51:34,985
And vegetation dies.
554
00:51:45,664 --> 00:51:52,269
Around the world, life
on land is being wiped out.
555
00:51:52,337 --> 00:51:54,104
And life
in the oceans,
556
00:51:54,172 --> 00:51:56,574
has also been
compromised.
557
00:51:58,510 --> 00:52:03,948
The waters turn pink.
558
00:52:07,286 --> 00:52:11,656
Plants, trilobites, and
predators, disappear.
559
00:52:20,831 --> 00:52:22,999
The new, hotter
atmosphere heated the
560
00:52:23,067 --> 00:52:27,170
oceans and stripped
them of oxygen.
561
00:52:27,438 --> 00:52:29,973
Now, this pink algae
is one of the few life
562
00:52:30,041 --> 00:52:34,745
forms that can survive
in the stagnant water.
563
00:52:34,913 --> 00:52:37,848
The Siberian eruptions
transform the entire
564
00:52:37,916 --> 00:52:40,918
planet, nothing, not
even the deepest ocean
565
00:52:40,986 --> 00:52:45,623
floor, is beyond
their reach.
566
00:52:52,564 --> 00:52:55,132
Bubbles of methane gas
escape from beneath the
567
00:52:55,200 --> 00:52:57,401
sea bed.
568
00:53:01,506 --> 00:53:04,108
Methane is a
greenhouse gas,
569
00:53:04,175 --> 00:53:07,679
at least twenty times
deadlier than carbon dioxide.
570
00:53:09,782 --> 00:53:12,817
Until now, the gas
has been frozen.
571
00:53:12,885 --> 00:53:15,220
But as the sea
temperature rises,
572
00:53:15,288 --> 00:53:18,123
it begins to melt.
573
00:53:31,470 --> 00:53:33,305
Released into
the atmosphere,
574
00:53:33,372 --> 00:53:35,940
this powerful gas
pushes up temperatures
575
00:53:36,008 --> 00:53:39,643
even further.
576
00:53:39,878 --> 00:53:42,880
It's now almost
105 degrees,
577
00:53:42,948 --> 00:53:45,282
11 degrees hotter than
before the Siberian
578
00:53:45,350 --> 00:53:47,318
eruptions.
579
00:53:51,924 --> 00:53:54,793
Creatures that survive
the initial destruction
580
00:53:54,861 --> 00:53:58,464
now face a new and
deadly environment.
581
00:53:58,532 --> 00:54:02,435
Few will live.
582
00:54:02,870 --> 00:54:05,471
It's been five hundred
thousand years since
583
00:54:05,539 --> 00:54:07,740
the eruptions
first began,
584
00:54:07,808 --> 00:54:11,377
And all this time, the
lava's been pouring out.
585
00:54:13,280 --> 00:54:16,082
By now, it covers an
area the size of the
586
00:54:16,150 --> 00:54:18,785
United States with a
layer of molten rock
587
00:54:18,852 --> 00:54:24,156
nearly 4 miles deep.
588
00:54:26,392 --> 00:54:32,030
95 per cent of the
species are gone.
589
00:54:32,665 --> 00:54:36,167
A few survive by eating
anything they can find
590
00:54:36,235 --> 00:54:41,172
and living in
burrows underground.
591
00:54:44,344 --> 00:54:49,649
But everything
else, is dead.
592
00:54:49,716 --> 00:54:53,553
250 million years ago,
the Earth reverts back
593
00:54:53,621 --> 00:54:56,890
to an almost
lifeless planet.
594
00:54:56,958 --> 00:55:00,093
But that's about
to change, again.
595
00:55:06,436 --> 00:55:08,036
It's
been fifty million
596
00:55:08,104 --> 00:55:10,739
years since virtually
all life on Earth was
597
00:55:10,806 --> 00:55:13,575
wiped out.
598
00:55:13,776 --> 00:55:16,677
And the planet has
been transformed.
599
00:55:19,748 --> 00:55:23,217
It's now 200
million years ago,
600
00:55:23,285 --> 00:55:26,287
and just one
supercontinent, Pangea,
601
00:55:26,354 --> 00:55:30,057
stretches from
pole to pole.
602
00:55:35,865 --> 00:55:38,433
After the trauma of
the mass extinction,
603
00:55:38,501 --> 00:55:41,303
the planet heals.
604
00:55:41,371 --> 00:55:44,740
Temperatures stabilize;
the acid rain
605
00:55:44,807 --> 00:55:48,210
neutralizes and
vegetation returns.
606
00:55:50,080 --> 00:55:52,448
With 95 per cent of all
life on Earth wiped
607
00:55:52,516 --> 00:55:56,419
out, the field opens
for a new species to
608
00:55:56,487 --> 00:55:58,288
emerge.
609
00:55:58,522 --> 00:56:00,790
One that will dominate
the planet like no
610
00:56:00,858 --> 00:56:02,725
other.
611
00:56:09,398 --> 00:56:13,467
The dinosaurs.
612
00:56:13,602 --> 00:56:17,105
These are called
Ammosaurs.
613
00:56:17,172 --> 00:56:19,341
Like all dinos, they
evolved from the
614
00:56:19,408 --> 00:56:25,880
reptiles that survived
the Permian Extinction.
615
00:56:26,349 --> 00:56:30,151
At 15 feet tall, their
size makes them slow,
616
00:56:30,219 --> 00:56:33,188
and vulnerable.
617
00:56:39,994 --> 00:56:46,599
Nearby is the
dilophosaurus.
618
00:56:49,502 --> 00:56:54,539
It's small,
619
00:56:54,607 --> 00:56:56,742
and fast.
620
00:57:17,667 --> 00:57:19,734
The ammosaurus is too
big a meal for one
621
00:57:19,801 --> 00:57:22,403
dilophosaurus.
622
00:57:22,471 --> 00:57:24,438
But not for two.
623
00:57:39,155 --> 00:57:42,191
The dinosaurs have
repopulated the Earth.
624
00:57:42,826 --> 00:57:45,962
But no species can
tame this restless,
625
00:57:46,029 --> 00:57:48,197
volatile planet.
626
00:57:54,105 --> 00:57:56,073
The earth's crust
is thinning.
627
00:57:56,140 --> 00:57:58,041
It's releasing lava
and shaking with
628
00:57:58,109 --> 00:58:01,144
earthquakes, as if
being stretched by some
629
00:58:01,212 --> 00:58:03,413
unseen force.
630
00:58:09,585 --> 00:58:11,920
It's also happening
near what will become
631
00:58:11,988 --> 00:58:16,224
North America's
eastern seaboard.
632
00:58:24,399 --> 00:58:28,302
The Earth's plates are
on the move again.
633
00:58:28,370 --> 00:58:30,371
190 million years
ago, the great
634
00:58:30,439 --> 00:58:34,174
super-continent of
Pangea tears apart.
635
00:58:39,114 --> 00:58:41,081
A vast slab of
land breaks away,
636
00:58:41,149 --> 00:58:44,284
creating a chasm.
637
00:58:44,352 --> 00:58:47,620
It fills with a new
ocean called the Tethys
638
00:58:47,688 --> 00:58:51,791
over what will one day
be the Middle East.
639
00:58:57,397 --> 00:58:59,365
Currents push
nutrients up into
640
00:58:59,433 --> 00:59:04,838
the coastal waters.
641
00:59:04,905 --> 00:59:07,407
And the nutrients
attract fish,
642
00:59:07,475 --> 00:59:14,348
in the millions.
643
00:59:14,415 --> 00:59:22,522
But again, with so much
life, also comes death.
644
00:59:22,590 --> 00:59:28,194
Dead fish and plankton
carpet the ocean floor.
645
00:59:28,261 --> 00:59:30,496
Over the next 10
million years,
646
00:59:30,564 --> 00:59:33,232
layers of rock
will bury and heat
647
00:59:33,299 --> 00:59:35,967
the dead creatures.
648
00:59:36,035 --> 00:59:37,369
Ancient fish and
649
00:59:37,436 --> 00:59:43,409
plankton will
become oil.
650
00:59:55,823 --> 00:59:58,926
Every gallon of
gas in our cars,
651
00:59:58,993 --> 01:00:01,896
every piece of plastic
on the planet,
652
01:00:01,963 --> 01:00:04,465
the paint on our walls,
the carpet under our
653
01:00:04,533 --> 01:00:08,203
feet, even the
soap we wash with,
654
01:00:08,271 --> 01:00:17,079
almost all originated
in this way.
655
01:00:24,320 --> 01:00:27,455
180 million years ago,
the North American
656
01:00:27,522 --> 01:00:30,424
plate is still moving
away from the European
657
01:00:30,492 --> 01:00:39,733
and Asian plate.
658
01:00:39,801 --> 01:00:42,570
It's shifting about
one inch each year,
659
01:00:42,638 --> 01:00:49,444
the same speed at which
our fingernails grow.
660
01:00:49,512 --> 01:00:52,715
But fast forward 35
million years and a new
661
01:00:52,783 --> 01:00:58,954
ocean forms, as well
as new continents.
662
01:00:59,022 --> 01:01:00,889
The United States
breaks away from
663
01:01:00,957 --> 01:01:05,660
Africa.
664
01:01:05,728 --> 01:01:08,963
The world as we
know it takes shape.
665
01:01:09,030 --> 01:01:11,965
The chasm between the
two continents fills,
666
01:01:12,033 --> 01:01:19,205
creating the
Atlantic Ocean.
667
01:01:22,843 --> 01:01:29,949
And in the middle,
lies a volcano.
668
01:01:30,017 --> 01:01:32,785
Like before, currents
deep beneath the
669
01:01:32,852 --> 01:01:41,394
Earth's crust move
the plates again.
670
01:01:54,940 --> 01:01:58,209
The entire sea floor
tears in two and is
671
01:01:58,277 --> 01:01:59,945
pushed up into
a ridge of
672
01:02:00,012 --> 01:02:05,151
mountains and volcanoes.
673
01:02:05,219 --> 01:02:07,387
It grows higher
than the Himalayas,
674
01:02:07,454 --> 01:02:10,391
and longer than
the Rockies.
675
01:02:10,458 --> 01:02:15,330
The water here is hot,
as molten lava forces
676
01:02:15,398 --> 01:02:22,204
its way out from deep
inside the earth.
677
01:02:22,271 --> 01:02:25,274
As the lava cools, it
creates a new range of
678
01:02:25,342 --> 01:02:32,214
volcanic mountains,
and a new ocean floor.
679
01:02:32,282 --> 01:02:35,651
Pangea breaks apart,
and our world
680
01:02:35,719 --> 01:02:44,127
rearranges again.
681
01:02:56,142 --> 01:02:59,043
It's this geological
activity that makes the
682
01:02:59,111 --> 01:03:04,782
Earth restless,
creative and unique.
683
01:03:04,850 --> 01:03:06,884
And every time the
planet reinvents
684
01:03:06,952 --> 01:03:15,526
itself, its inhabitants
adapt and evolve.
685
01:03:19,598 --> 01:03:24,904
Like the ichthyosaurs.
686
01:03:24,971 --> 01:03:27,840
Their reptile ancestors
lived on land,
687
01:03:27,908 --> 01:03:29,976
but as the
planet changed,
688
01:03:30,044 --> 01:03:32,312
so did these
animals.
689
01:03:32,380 --> 01:03:33,981
They grew fins and
moved into the newly
690
01:03:34,048 --> 01:03:41,889
formed Atlantic Ocean.
691
01:03:41,957 --> 01:03:44,292
This one is
20 feet long,
692
01:03:44,359 --> 01:03:53,534
and can travel at a
quick 25 miles an hour.
693
01:03:55,337 --> 01:03:57,772
It's the ocean's
fastest creature and
694
01:03:57,840 --> 01:03:59,707
most efficient
predator.
695
01:03:59,775 --> 01:04:08,216
It rules the oceans
for 50 million years.
696
01:04:19,429 --> 01:04:28,003
But now, there's
a new contender.
697
01:04:37,313 --> 01:04:42,984
The pliosaur.
698
01:04:43,052 --> 01:04:46,521
Longer than a bus, and
as heavy as a truck,
699
01:04:46,589 --> 01:04:49,524
its jaws are eight
times more powerful
700
01:04:49,592 --> 01:04:52,094
than a great
white sharks',
701
01:04:52,161 --> 01:05:00,502
with teeth 12
inches long.
702
01:05:08,512 --> 01:05:10,947
The Earth, and
its inhabitants,
703
01:05:11,014 --> 01:05:13,883
have changed beyond
recognition.
704
01:05:13,951 --> 01:05:16,785
This was once
solid ground,
705
01:05:16,853 --> 01:05:20,456
now it's the
Atlantic Ocean.
706
01:05:20,524 --> 01:05:23,326
The very spot where
ammosaurs grazed and
707
01:05:23,394 --> 01:05:26,829
dilophosaurs
stalked their prey.
708
01:05:26,897 --> 01:05:29,432
The dinosaurs' world
may be different,
709
01:05:29,500 --> 01:05:32,101
but they're as
dominant as ever.
710
01:05:32,169 --> 01:05:35,071
They appear invincible.
711
01:05:45,280 --> 01:05:46,580
They're one
of the planet's most
712
01:05:46,648 --> 01:05:49,216
successful species.
713
01:05:49,284 --> 01:05:52,685
They've survived
volcanic eruptions,
714
01:05:52,753 --> 01:05:55,154
earthquakes, and entire
continents splitting
715
01:05:55,222 --> 01:06:01,493
apart, The dinosaurs
have thrived for 165
716
01:06:01,561 --> 01:06:09,934
million years.
717
01:06:10,002 --> 01:06:12,670
A number of mammals
have also survived,
718
01:06:12,738 --> 01:06:21,246
like this
shrew-like animal.
719
01:06:21,313 --> 01:06:24,015
They're prey to
the dinosaurs.
720
01:06:24,083 --> 01:06:26,551
So they live in trees
or underground,
721
01:06:26,618 --> 01:06:30,855
and venture out
only at night.
722
01:06:30,922 --> 01:06:39,796
Mammals pose no threat
to the dinosaurs.
723
01:06:41,265 --> 01:06:43,233
Nothing on Earth
can challenge their
724
01:06:43,300 --> 01:06:52,142
dominance.
725
01:06:56,381 --> 01:07:03,188
Nothing, on Earth.
726
01:07:03,255 --> 01:07:05,224
A large piece
of space rock,
727
01:07:05,292 --> 01:07:13,999
heads toward Earth.
728
01:07:14,067 --> 01:07:17,570
This asteroid is at
least 6 miles across,
729
01:07:17,637 --> 01:07:21,908
and travelling over
40,000 miles an hour.
730
01:07:21,976 --> 01:07:30,950
It's bigger than
Mount Everest,
731
01:07:31,952 --> 01:07:41,661
and heads straight for
the Gulf of Mexico.
732
01:07:46,200 --> 01:07:49,335
It travels so fast that
its impact would be
733
01:07:49,403 --> 01:07:56,275
missed in a
blink of an eye.
734
01:07:56,343 --> 01:08:03,749
A split second changes
the world forever.
735
01:08:07,587 --> 01:08:09,955
At impact, the
asteroid's back edge
736
01:08:10,023 --> 01:08:19,697
stands at 35,000 feet.
737
01:08:30,309 --> 01:08:33,177
It strikes with such
immense force that it
738
01:08:33,245 --> 01:08:42,422
destroys
everything it hits.
739
01:08:53,201 --> 01:09:01,676
The asteroid itself
instantly vaporizes,
740
01:09:01,744 --> 01:09:03,778
unleashing the
energy of millions
741
01:09:03,846 --> 01:09:11,619
of nuclear weapons.
742
01:09:11,687 --> 01:09:13,288
Nowhere is safe,
743
01:09:13,356 --> 01:09:20,763
with debris flying
everywhere.
744
01:09:20,831 --> 01:09:23,499
Debris as big as
entire city blocks
745
01:09:23,567 --> 01:09:32,708
circle the Earth.
746
01:09:40,951 --> 01:09:44,086
The blastwave races out
from the impact zone
747
01:09:44,154 --> 01:09:52,595
like shrapnel from
an exploding bomb.
748
01:10:22,893 --> 01:10:25,327
Minutes after impact,
hundreds of miles
749
01:10:25,395 --> 01:10:27,663
from where the
asteroid struck,
750
01:10:27,730 --> 01:10:36,172
the earth is
under attack.
751
01:10:36,240 --> 01:10:44,649
Boulders rain down.
752
01:10:44,716 --> 01:10:51,922
Earthquakes
shake the ground.
753
01:10:51,990 --> 01:10:59,796
And tsunamis
batter the coasts.
754
01:11:08,071 --> 01:11:12,274
But the onslaught
has only just begun.
755
01:11:12,342 --> 01:11:14,877
The plume of molten
rock and dust spreads
756
01:11:14,945 --> 01:11:19,315
out, and engulfs
the planet.
757
01:11:19,383 --> 01:11:27,757
The entire sky acts
like a giant lamp,
758
01:11:27,825 --> 01:11:28,891
heating the
Earth's surface to
759
01:11:28,959 --> 01:11:32,562
over 500 degrees.
760
01:11:32,630 --> 01:11:41,773
Vegetation
spontaneously ignites.
761
01:11:47,714 --> 01:11:49,882
Even months
after the impact,
762
01:11:49,950 --> 01:11:51,817
smoke and ash
still block out
763
01:11:51,885 --> 01:11:55,287
the sun's rays.
764
01:11:55,355 --> 01:11:58,423
And with less sunlight,
plants die and the
765
01:11:58,491 --> 01:12:07,968
animals starve.
766
01:12:16,310 --> 01:12:18,511
65 million years ago,
767
01:12:18,578 --> 01:12:20,847
the impact has blasted,
768
01:12:20,914 --> 01:12:29,555
stoned and burnt
the dinosaurs.
769
01:12:31,424 --> 01:12:40,666
Their 165 million year
reign is over.
770
01:12:44,271 --> 01:12:46,439
But the dinosaur's
demise brings
771
01:12:46,506 --> 01:12:53,945
opportunity for
another species.
772
01:12:54,013 --> 01:12:58,950
A mammal.
773
01:12:59,018 --> 01:13:01,787
By living underground,
mammals have avoided
774
01:13:01,854 --> 01:13:04,690
the heat and fires.
775
01:13:04,758 --> 01:13:08,061
And by eating anything,
they thrive while more
776
01:13:08,129 --> 01:13:14,869
selective eaters die.
777
01:13:14,936 --> 01:13:17,271
They're the unlikely
inheritors of the
778
01:13:17,339 --> 01:13:26,047
dinosaurs' crown.
779
01:13:27,750 --> 01:13:30,018
And as one story ends.
780
01:13:30,086 --> 01:13:32,087
Another begins.
781
01:13:32,154 --> 01:13:34,622
With the dinosaurs
out of the way,
782
01:13:34,690 --> 01:13:38,859
our ancestors' may now
have a chance, at life.
783
01:13:56,837 --> 01:14:00,405
The dinosaurs
are long dead.
784
01:14:00,807 --> 01:14:07,011
The planet is peaceful.
785
01:14:07,079 --> 01:14:09,279
In this new
world, our mammal
786
01:14:09,347 --> 01:14:16,820
ancestors are evolving.
787
01:14:23,063 --> 01:14:26,198
47 million years
ago, this lake,
788
01:14:26,266 --> 01:14:28,635
in what will one
day be Germany,
789
01:14:28,702 --> 01:14:37,977
is the perfect
place to spot them.
790
01:14:47,487 --> 01:14:49,988
Unlike earlier
mammals, its eyes and
791
01:14:50,056 --> 01:14:54,459
brain are bigger.
792
01:14:54,527 --> 01:14:59,765
This is Darwinius
Massilae, or Ida.
793
01:14:59,833 --> 01:15:02,301
She looks nothing
like humans,
794
01:15:02,369 --> 01:15:04,937
but fossil evidence
today indicates that
795
01:15:05,005 --> 01:15:08,208
these creatures might
evolve into monkeys,
796
01:15:08,276 --> 01:15:15,784
apes, and
eventually humans.
797
01:15:15,851 --> 01:15:18,553
Looking back through
47 million years of
798
01:15:18,620 --> 01:15:21,589
evolution might reveal
one of our earliest
799
01:15:21,657 --> 01:15:26,629
known ancestors.
800
01:15:26,696 --> 01:15:30,266
The lake sits on a
volcanic crater.
801
01:15:30,334 --> 01:15:35,405
It belches out
noxious gas,
802
01:15:35,473 --> 01:15:43,713
that eventually
kills Ida.
803
01:15:47,051 --> 01:15:48,551
The lake preserves
her in its
804
01:15:48,619 --> 01:15:54,624
oxygen depleted depths.
805
01:15:54,691 --> 01:15:57,960
One day, when the water
is gone and Ida's
806
01:15:58,028 --> 01:16:03,966
fossil is found, this
primitive primate could
807
01:16:04,034 --> 01:16:07,002
help piece together the
beginning of our own
808
01:16:07,070 --> 01:16:15,644
story, the story
of human life.
809
01:16:15,711 --> 01:16:17,613
We're closer to
understanding how
810
01:16:17,680 --> 01:16:20,650
everything we've seen,
from ocean bacteria,
811
01:16:20,717 --> 01:16:23,186
through walking fish
and subterranean
812
01:16:23,254 --> 01:16:27,658
rodents, leads to us.
813
01:16:27,726 --> 01:16:29,427
And to understanding
how our
814
01:16:29,494 --> 01:16:35,267
planet was made.
815
01:16:35,335 --> 01:16:38,370
47 million years
ago, the atmosphere
816
01:16:38,438 --> 01:16:45,177
is much like today.
817
01:16:45,245 --> 01:16:48,680
The temperature
is 75 degrees.
818
01:16:48,748 --> 01:16:50,716
And a day lasts
just under
819
01:16:50,784 --> 01:16:53,652
twenty four hours.
820
01:16:53,720 --> 01:16:56,288
The Earth is now
almost identical to
821
01:16:56,356 --> 01:16:59,324
the planet we call home.
822
01:16:59,392 --> 01:17:07,833
Almost.
823
01:17:17,010 --> 01:17:23,616
The Earth's plates are
on the move again.
824
01:17:23,684 --> 01:17:32,057
India moves north
toward Asia.
825
01:17:40,401 --> 01:17:42,802
The Indian and Asian
plates are locked
826
01:17:42,870 --> 01:17:52,147
in a titanic struggle,
827
01:17:53,783 --> 01:17:58,520
and neither plate
is winning.
828
01:17:58,588 --> 01:18:01,057
As they buckle, the
ocean floor contorts
829
01:18:01,124 --> 01:18:09,267
upward along a
1,500 mile line.
830
01:18:12,237 --> 01:18:14,271
A vast mountain
range rises up
831
01:18:14,339 --> 01:18:23,047
over 27,000 feet.
832
01:18:38,296 --> 01:18:46,970
These are the
Himalayas.
833
01:18:50,708 --> 01:18:53,209
And the highest
mountain of all,
834
01:18:53,277 --> 01:19:01,951
Mount Everest.
835
01:19:02,019 --> 01:19:03,920
Its summit reaches
up into the
836
01:19:03,988 --> 01:19:06,523
Earth's jet stream,
the same altitude
837
01:19:06,591 --> 01:19:16,166
where planes fly.
838
01:19:32,614 --> 01:19:34,881
When the snow on
the peaks melts,
839
01:19:34,949 --> 01:19:38,285
it feeds rivers like
the Ganges, Indus,
840
01:19:38,353 --> 01:19:46,560
Yellow and Yangtze.
841
01:19:46,627 --> 01:19:49,830
The Himalayas are like
a vast water tower.
842
01:19:49,898 --> 01:19:52,533
One day, their rivers
will supply water for
843
01:19:52,600 --> 01:20:00,742
almost half the
world's population.
844
01:20:10,621 --> 01:20:16,360
20 million years ago,
this is our planet,
845
01:20:16,427 --> 01:20:18,462
with every continent,
and every ocean
846
01:20:18,529 --> 01:20:25,635
as we know it.
847
01:20:25,703 --> 01:20:28,872
Except one thing
is still missing,
848
01:20:28,939 --> 01:20:35,512
the human race.
849
01:20:35,580 --> 01:20:37,815
And for humans
to evolve,
850
01:20:37,882 --> 01:20:41,418
something needs
to change.
851
01:20:57,998 --> 01:20:59,266
Along the African
852
01:20:59,333 --> 01:21:06,941
coast, a great
rift opens up.
853
01:21:09,745 --> 01:21:18,353
It stretches
nearly 4,000 miles,
854
01:21:19,055 --> 01:21:27,829
with mountains growing
along its edge.
855
01:21:40,476 --> 01:21:43,478
This ape-like creature
may stay in these trees
856
01:21:43,546 --> 01:21:50,353
forever, but its
world is changing.
857
01:21:50,421 --> 01:21:53,423
The growing mountains
act like a wall,
858
01:21:53,491 --> 01:21:55,792
prohibiting moisture
from the Indian Ocean
859
01:21:55,860 --> 01:21:59,396
from passing
over the land.
860
01:21:59,463 --> 01:22:03,299
It's getting
hotter, and drier.
861
01:22:03,367 --> 01:22:05,801
The lush rainforest
becomes an arid
862
01:22:05,869 --> 01:22:09,872
savannah.
863
01:22:09,939 --> 01:22:12,574
The new hotter climate
changes the creatures'
864
01:22:12,642 --> 01:22:15,410
habitat, forcing them
to search further for
865
01:22:15,478 --> 01:22:19,715
food, soon, they stop
dragging their knuckles
866
01:22:19,783 --> 01:22:21,449
like apes.
867
01:22:21,517 --> 01:22:27,189
And begin to stand,
and walk on two feet.
868
01:22:27,256 --> 01:22:28,957
It's the most
important step in
869
01:22:29,025 --> 01:22:36,166
the human story.
870
01:22:36,233 --> 01:22:38,768
This mountain range
could be the reason
871
01:22:38,836 --> 01:22:46,909
humans
walk on two feet.
872
01:22:48,411 --> 01:22:51,580
The random movement of
two plates may have
873
01:22:51,648 --> 01:22:54,149
kick-started a chain of
events that leads to
874
01:22:54,217 --> 01:22:59,954
the first humans.
875
01:23:11,701 --> 01:23:13,468
A man and child.
876
01:23:13,536 --> 01:23:16,237
A scene very
much like today.
877
01:23:16,305 --> 01:23:20,976
But it's one and a half
million years ago.
878
01:23:21,043 --> 01:23:24,079
They are an early
species of human called
879
01:23:24,146 --> 01:23:28,149
Homo Erectus.
880
01:23:28,217 --> 01:23:30,852
And these are the first
footprints like our
881
01:23:30,919 --> 01:23:38,259
own; civilizations
past and present,
882
01:23:38,326 --> 01:23:41,061
everyone that's
ever lived,
883
01:23:41,129 --> 01:23:43,265
the greatest
inventions,
884
01:23:43,333 --> 01:23:45,834
the most
brilliant ideas.
885
01:23:45,902 --> 01:23:49,272
Human history, in all
its complexity and
886
01:23:49,339 --> 01:23:58,281
splendor, begins
here and now.
887
01:24:10,694 --> 01:24:13,062
The climate
changes again.
888
01:24:13,130 --> 01:24:17,767
70,000 years ago
sea levels fall.
889
01:24:17,835 --> 01:24:20,203
And the gap between
Africa and Arabia
890
01:24:20,271 --> 01:24:28,679
shrinks to just
eight miles.
891
01:24:28,747 --> 01:24:31,381
The Red Sea is now
narrow and shallow
892
01:24:31,449 --> 01:24:34,318
enough for a small
group to cross,
893
01:24:34,385 --> 01:24:38,456
out of Africa.
894
01:24:38,523 --> 01:24:41,259
They're another later
species of human,
895
01:24:41,326 --> 01:24:49,767
called Homo Sapiens.
896
01:24:59,409 --> 01:25:02,711
Scientists believe that
the entire world beyond
897
01:25:02,779 --> 01:25:05,881
Africa was populated
from descendants of
898
01:25:05,949 --> 01:25:12,153
these two hundred
individuals.
899
01:25:12,221 --> 01:25:15,457
Over time our ancestors
multiply and spread
900
01:25:15,524 --> 01:25:24,033
out; to India, onto
Asia and into Europe.
901
01:25:36,047 --> 01:25:38,248
But while humans
head north,
902
01:25:38,315 --> 01:25:47,524
a giant wall of
ice travels south.
903
01:25:47,591 --> 01:25:51,294
Europe, 40,000
years ago.
904
01:25:51,362 --> 01:25:54,831
Homo sapiens arrive,
only to find a world
905
01:25:54,899 --> 01:25:57,900
that's quickly
changing.
906
01:25:57,968 --> 01:26:00,036
It should be the
height of summer,
907
01:26:00,104 --> 01:26:02,139
but it's
getting colder.
908
01:26:02,206 --> 01:26:03,974
The plants are
frostbitten,
909
01:26:04,042 --> 01:26:08,179
and the rivers
are frozen.
910
01:26:08,247 --> 01:26:10,582
Natural changes in
the Earth's orbit,
911
01:26:10,649 --> 01:26:13,752
CO2 levels, and the
flow of warm water
912
01:26:13,819 --> 01:26:16,188
around the planet
conspire to lower the
913
01:26:16,256 --> 01:26:18,624
Earth's temperature.
914
01:26:18,692 --> 01:26:20,860
The Earth, and
its inhabitants,
915
01:26:20,927 --> 01:26:23,963
enter an ice age.
916
01:26:24,031 --> 01:26:27,333
Glaciers as high as
skyscrapers creep over
917
01:26:27,401 --> 01:26:32,738
the northern hemisphere
about a foot every day,
918
01:26:32,806 --> 01:26:35,741
Slow, and powerful,
they sculpt the
919
01:26:35,809 --> 01:26:41,247
landscape, gouging out
great depressions.
920
01:26:41,315 --> 01:26:48,856
The planet will never
look the same again.
921
01:26:48,924 --> 01:26:51,826
Now, around twenty
thousand years ago,
922
01:26:51,893 --> 01:26:55,496
they grind to a halt.
923
01:26:55,564 --> 01:26:57,965
Much of the northern
hemisphere is covered
924
01:26:58,033 --> 01:27:07,141
by ice sheets up to one
and a half miles thick.
925
01:27:09,744 --> 01:27:12,046
With trillions of
gallons of water locked
926
01:27:12,114 --> 01:27:18,619
up as ice, sea
levels fall.
927
01:27:18,687 --> 01:27:21,255
A strip of land emerges
from the ocean between
928
01:27:21,323 --> 01:27:29,832
Siberia and Alaska.
929
01:27:29,899 --> 01:27:34,604
It's a bridge between
two vast continents,
930
01:27:34,672 --> 01:27:38,107
a gateway that takes
humans from Asia to a
931
01:27:38,175 --> 01:27:43,245
new world,
the Americas.
932
01:27:43,313 --> 01:27:45,381
They're the last great
continents to be
933
01:27:45,448 --> 01:27:49,985
colonized, the last
great human migration,
934
01:27:50,053 --> 01:27:57,826
and the first
Americans.
935
01:28:04,234 --> 01:28:07,703
Now, 14,000 years
ago, the changes that
936
01:28:07,771 --> 01:28:12,541
triggered the
ice age reverse.
937
01:28:12,609 --> 01:28:15,344
As the ice retreats,
it reveals a very
938
01:28:15,412 --> 01:28:19,148
different northern
hemisphere.
939
01:28:19,215 --> 01:28:21,217
The huge depressions
that the glaciers
940
01:28:21,284 --> 01:28:23,986
create fill with
water to become North
941
01:28:24,054 --> 01:28:33,197
America's Great Lakes.
942
01:28:40,338 --> 01:28:43,540
6,000 years ago, the
ice retreats back to
943
01:28:43,608 --> 01:28:52,682
the poles, toward the
Arctic and Antarctic.
944
01:29:05,030 --> 01:29:08,099
After a four and a half
billion year journey,
945
01:29:08,167 --> 01:29:12,438
we're, finally home.
946
01:29:12,505 --> 01:29:18,844
This is our
world, our time.
947
01:29:18,912 --> 01:29:21,447
The planet's incredible
story helps us
948
01:29:21,514 --> 01:29:25,050
understand how and why
everything around us is
949
01:29:25,118 --> 01:29:32,690
here today.
950
01:29:32,757 --> 01:29:39,997
From the skies above.
951
01:29:40,065 --> 01:29:47,640
To water, the essential
ingredient for life.
952
01:29:47,707 --> 01:29:56,383
To the ground
beneath our feet.
953
01:29:56,450 --> 01:30:03,856
And finally life,
a chain of catastrophes
954
01:30:03,924 --> 01:30:06,291
and coincidences,
creating a
955
01:30:06,359 --> 01:30:10,395
spectacular result.
956
01:30:10,463 --> 01:30:13,264
Each triumph and
disaster is a step
957
01:30:13,332 --> 01:30:18,635
leading to here,
each and every one of
958
01:30:18,703 --> 01:30:23,407
us, right now.
959
01:30:23,475 --> 01:30:29,280
But the Earth's
story isn't over.
960
01:30:29,348 --> 01:30:33,018
This journey is only
half the story.
961
01:30:33,086 --> 01:30:38,023
A lot more is
yet to come.
962
01:30:38,091 --> 01:30:41,460
The Earth will live for
at least another 4.5
963
01:30:41,528 --> 01:30:50,735
billion years.
964
01:30:53,272 --> 01:30:57,976
More wonders,
more terrors,
965
01:30:58,044 --> 01:31:00,578
and more strange
creatures lie ahead for
966
01:31:00,646 --> 01:31:08,120
our restless and
creative planet.
967
01:31:08,187 --> 01:31:11,156
The next chapter of
Earth's story is still
968
01:31:11,223 --> 01:31:17,829
to be written.
969
01:31:17,854 --> 01:31:21,854
-- sync, corrected by elderman --
65761
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