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I've come here to Southwestern
France to the Pyrenees
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and then deep into a mountain,
more than half a kilometre
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00:00:56,000 --> 00:00:58,576
through a labyrinth
of damp and dark caves,
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00:00:58,600 --> 00:01:02,496
into this enormous
and remarkable cavern.
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But I've come here to show you
something very special.
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Look at this.
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No less than eight bison...
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..drawn on this cave wall.
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Absolutely beautiful.
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But it's not just these bison.
Have a look at this panel over here!
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Here, we don't just see bison -
we see primitive horses, tarpan.
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And look there, a Pyrenean ibex.
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Absolutely sensational.
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Now, I've stood in art galleries
all over the world looking at art,
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but this is the
oldest I've seen by far.
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And possibly the most
beautiful and most moving.
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The drawings of these animals
are so fresh,
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so accurate, so beautifully made.
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For me, this is about being human.
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This is about our history.
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The cave paintings
are the culmination of a story
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that began long before the
first humans set foot on Earth...
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..deep within our planet's past...
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LOUD EXPLOSION
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..when the world of the dinosaurs...
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..was destroyed...
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..making way for the
rise of the mammals.
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It's a tale of turmoil and upheaval,
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00:03:00,840 --> 00:03:04,616
of millions of years
of climate swings
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00:03:04,640 --> 00:03:07,800
from one extreme to another.
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Until, out of the chaos,
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our species was born.
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A species capable of creating art
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on a cave wall in Southern France.
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Now, we think that these were
drawn around 13,000 years ago.
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00:03:28,680 --> 00:03:33,136
And that's significant because
it constitutes a turning point,
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not just for our species,
but for the planet,
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because we were going on to be
a significantly powerful force,
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00:03:41,080 --> 00:03:45,160
capable of transforming
and reshaping the Earth.
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In the time since the
cave paintings were done,
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00:03:53,120 --> 00:03:57,120
we've radically altered
life on the planet...
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..in ways our ancient ancestors
could never have imagined.
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00:04:07,600 --> 00:04:10,896
And so we've reached a unique
point in our planet's
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4.5 billion year history,
when an intelligent species,
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with a clear understanding
of the Earth,
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is transforming it
at an incredible speed.
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And that species is,
of course, us.
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66 million years ago,
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one form of life dominated
the surface of the Earth.
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DEEP GROWLING
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Dinosaurs.
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These magnificent creatures, amongst
the largest that have ever lived
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00:05:20,840 --> 00:05:26,600
on Earth, had reigned supreme
for around 150 million years.
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They had evolved into
many hundreds of species,
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00:05:37,120 --> 00:05:40,640
spread across every continent
on the planet.
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00:05:48,160 --> 00:05:51,480
But all that was about to change.
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00:06:22,520 --> 00:06:26,376
What a wonderful place,
packed full of life.
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I've just been looking up
into the forest here.
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Tanagers, aracari, orioles -
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00:06:32,560 --> 00:06:34,936
a mass of species.
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00:06:34,960 --> 00:06:38,656
Now, of course, all of them
are individually beautiful.
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00:06:38,680 --> 00:06:42,696
But, for me, it's when
they form that complex web,
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when they knit together to
form a dynamic, harmonious,
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functional ecosystem that things
become even more beautiful.
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00:06:51,880 --> 00:06:53,816
But I've got to say, of course,
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that none of these species
were predestined.
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They weren't "meant to be".
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In fact, they were only here because
of a single, freak, chance event.
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An event of unimaginable violence
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00:07:08,400 --> 00:07:10,736
and astonishing destruction.
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I'm talking, of course,
about that day 66 million years ago
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when the asteroid struck the Earth.
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You know the one -
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the one that's said
to have wiped out the dinosaurs.
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00:07:25,560 --> 00:07:28,816
Now, there has been lots
of debate about exactly
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00:07:28,840 --> 00:07:30,800
what killed the dinosaurs.
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Since the 1980s,
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scientists have believed the
main culprit was an asteroid...
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..from the far reaches
of the solar system,
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the size of Mount Everest...
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..and on a collision course
with Earth.
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00:08:05,880 --> 00:08:10,336
An extraordinary claim requires
some extraordinary evidence
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00:08:10,360 --> 00:08:13,816
and, let's be clear, claiming
that a six mile wide asteroid
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00:08:13,840 --> 00:08:16,376
crashed into the planet,
unleashing the power
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of a billion nuclear weapons
is an extraordinary claim.
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00:08:19,680 --> 00:08:21,616
So where is the evidence?
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Where is the smoking gun?
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Well, I'm sat in it.
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This is called a cenote.
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00:08:29,600 --> 00:08:32,016
It's a word that comes from
one of the Mayan languages.
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00:08:32,040 --> 00:08:35,720
It literally means hole
in the ground filled with water.
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00:08:36,920 --> 00:08:40,456
Now, take a look at this
map of this part of Mexico,
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the Yucatan Peninsula.
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When I superimpose the cenotes,
you see there's an enormous
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number of them, the landscape
is completely freckled.
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00:08:50,520 --> 00:08:52,936
But then look again in more detail.
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You see this here?
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There's an arc of these geological
features running across here.
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And if we complete the arc,
turning it into a circle,
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00:09:01,920 --> 00:09:06,856
it has a diameter of 110 miles,
which corresponds perfectly
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00:09:06,880 --> 00:09:10,336
with the inner rim
of the crater made
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00:09:10,360 --> 00:09:13,496
when the asteroid struck our planet.
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00:09:13,520 --> 00:09:16,336
Now, the cenotes weren't
formed at the time.
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Over millions of years,
that impact seems to have weakened
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00:09:19,440 --> 00:09:21,096
the rock here.
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00:09:21,120 --> 00:09:24,216
Water has leached through it,
forming cave systems,
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00:09:24,240 --> 00:09:28,656
which have collapsed in some places,
giving us this ring of cenotes.
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00:09:28,680 --> 00:09:31,400
HIGH PITCHED BIRD CALL
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00:09:36,080 --> 00:09:40,200
A devastating remnant
of the asteroid strike...
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..that brought the reign
of the dinosaurs to a crashing end.
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SHARP, LOUD BLAST
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00:10:00,840 --> 00:10:04,360
DEEP SCREECHING
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00:10:07,280 --> 00:10:10,680
LOUD RUMBLING
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00:10:14,480 --> 00:10:16,560
THUNDERING BOOM
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The blast annihilates
everything within its reach.
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00:10:33,000 --> 00:10:36,200
Earthquakes and tsunami
tear across the planet.
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And then it begins to rain.
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Not water...
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..but scorching hot rock...
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00:10:52,600 --> 00:10:56,296
DINOSAUR ROARS
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00:10:56,320 --> 00:10:59,776
..made from the asteroid
and the bedrock it had struck.
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00:10:59,800 --> 00:11:03,000
ANGUISHED ROARS
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00:11:06,760 --> 00:11:11,616
Truly one of THE worst days
in Earth's history.
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00:11:11,640 --> 00:11:15,360
DINOSAUR ROARS
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00:11:21,400 --> 00:11:24,736
But was this cataclysm enough
to kill the dinosaurs
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00:11:24,760 --> 00:11:27,240
all over the planet?
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00:11:32,360 --> 00:11:35,776
For a species to become
fully extinct,
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00:11:35,800 --> 00:11:41,056
every member of that species
has to die and not be replaced,
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00:11:41,080 --> 00:11:44,776
and not just in a small area
or even over a continent,
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00:11:44,800 --> 00:11:47,856
but over the entire world.
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00:11:47,880 --> 00:11:51,656
That's what extinction's really
about, that's what it entails.
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00:11:51,680 --> 00:11:56,440
And generally, it's not a dramatic
process, it's a slow burner.
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Have a look at this.
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00:12:00,480 --> 00:12:03,400
In my bag here,
I've got the skull...
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00:12:04,840 --> 00:12:08,616
..of an ornithomimid dinosaur -
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00:12:08,640 --> 00:12:10,936
one of a group of dinosaurs.
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These creatures looked
rather like giant ostrich
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00:12:14,600 --> 00:12:16,736
and they could run really fast.
139
00:12:16,760 --> 00:12:20,936
But the key thing is that these
ornithomimids can be found all over
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00:12:20,960 --> 00:12:23,296
the world in the fossil record.
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00:12:23,320 --> 00:12:26,880
So how did they become extinct?
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00:12:28,360 --> 00:12:32,416
Well, those that were unlucky enough
to be living within the blast radius
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of the asteroid,
the answer's simple -
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they just vaporised instantaneously.
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LOUD, DEEP BLAST
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And those living a
little further away,
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say within thousands of miles,
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well, it's likely they were killed
by the aftermath effects
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of that strike.
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00:12:53,120 --> 00:12:56,816
Things like earthquakes, tsunamis,
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the glass rain and the forest fires.
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00:13:00,240 --> 00:13:02,776
But what about the ornithomimids
that were living, say,
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on the other side of the world,
as far away as possible
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from the immediate carnage that
was caused by that asteroid?
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How did THEY die?
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Well, something else was needed to
cause the worldwide mass extinction.
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DEEP RUMBLING EXPLOSIONS
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00:13:29,960 --> 00:13:32,496
To seek answers to this puzzle,
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scientists have drilled deep
into the asteroid crater.
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The samples they've retrieved
reveal important clues.
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Such as the fine-grain debris
churned up by the powerful tsunami.
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As well as rocks like granite,
melted by the incredible temperature
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and pressure created by the impact.
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00:14:04,440 --> 00:14:10,136
But, crucially, one type of rock
that's known to exist in this area
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is missing from the place
where the asteroid hit.
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This is anhydrite.
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00:14:18,360 --> 00:14:20,096
Now, I know what you're thinking.
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You're thinking this is a
rather boring, grey rock.
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00:14:22,720 --> 00:14:28,056
But what's important is that it
contains large amounts of sulphur,
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and this is the final piece
of our extinction jigsaw
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because, when the asteroid struck,
it vaporised this rock,
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releasing no less than
300 billion tonnes of sulphur
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into the atmosphere.
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Today, there's virtually no trace
of anhydrite in the seabed
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within the crater...
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..because it was
all blasted into the air...
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..merging with ash and dust
to form a vast, grey cloud...
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..sweeping across the entire planet.
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00:15:30,680 --> 00:15:34,216
With the cloud blocking out
most of the sunlight,
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00:15:34,240 --> 00:15:37,200
temperatures plummet
by around 20 degrees.
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00:15:39,400 --> 00:15:42,400
But the extreme cold
isn't the only killer.
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In the dark, twilight conditions,
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00:15:48,680 --> 00:15:52,760
plants struggle to photosynthesise
and wither away.
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00:15:55,680 --> 00:16:00,600
And with virtually no plants to eat,
the food chain collapses.
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00:16:03,920 --> 00:16:07,240
Many dinosaurs starve to death.
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00:16:12,160 --> 00:16:16,056
When it came to the dinosaurs,
only a handful hung on to evolve
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into the 10,000 or so species
of birds that we have today.
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Three quarters of all animal
and plant species simply disappear.
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This was one of the worst extinction
events our planet has ever seen.
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00:17:02,760 --> 00:17:06,376
And yet, for our world to emerge,
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there needed to be some survivors.
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And most importantly from that
branch of life that we belong to...
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..the mammals.
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What a place.
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00:17:35,520 --> 00:17:38,456
It's not representative
of humanity's greatest attributes,
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00:17:38,480 --> 00:17:40,776
is it? It's a mess.
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00:17:40,800 --> 00:17:43,776
An apocalyptic landfill,
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screaming of waste and consumption.
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00:17:48,560 --> 00:17:50,736
I suppose the one thing
we can say is,
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"Look, nature's always
fighting back, isn't it?"
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Look at the plants here and,
out there, a whole host of wildfowl.
202
00:17:57,120 --> 00:17:59,896
But let's stick with the mammals
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00:17:59,920 --> 00:18:04,536
because 66 million years ago
they didn't all become extinct
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00:18:04,560 --> 00:18:08,816
and this is actually quite a good
place to find a modern creature
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00:18:08,840 --> 00:18:11,136
that shares some
real characteristics
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00:18:11,160 --> 00:18:13,136
with those early mammals,
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00:18:13,160 --> 00:18:17,136
and I happen to have a very
friendly one inside my jacket.
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What do you reckon?
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00:18:18,800 --> 00:18:19,840
I'll show you.
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Yes! The rat.
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00:18:23,600 --> 00:18:26,216
Now, I'm rather partial to rats,
I've got to say.
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00:18:26,240 --> 00:18:27,976
Just look at those whiskers.
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00:18:28,000 --> 00:18:30,016
Those lovely bright eyes.
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00:18:30,040 --> 00:18:32,576
But you might not be
quite so enamoured
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00:18:32,600 --> 00:18:36,656
when I tell you that our ancient
ancestors shared significant
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00:18:36,680 --> 00:18:40,536
similarities with
creatures like this rat.
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00:18:40,560 --> 00:18:44,496
So what was it that they had
that the dinosaurs didn't?
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00:18:44,520 --> 00:18:47,056
Well, many of the dinosaurs
were quite specialised.
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00:18:47,080 --> 00:18:50,936
The herbivores required very
particular species of plants to eat,
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00:18:50,960 --> 00:18:53,256
the carnivores very particular
species of dinosaurs.
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00:18:53,280 --> 00:18:56,456
But most of the early mammals,
they were generalists
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00:18:56,480 --> 00:18:59,376
and, equally importantly,
they were omnivores.
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00:18:59,400 --> 00:19:02,216
They could eat plant material
and flesh.
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00:19:02,240 --> 00:19:04,856
In fact, they could eat
rotting plant material
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00:19:04,880 --> 00:19:07,496
and rotting flesh,
and that was a real asset
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00:19:07,520 --> 00:19:11,400
when all of that starvation was
going on during the impact winter.
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00:19:12,440 --> 00:19:15,976
So, I have to tell you, that,
all of those millions of years ago,
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00:19:16,000 --> 00:19:20,216
animals like this represented hope.
229
00:19:20,240 --> 00:19:24,376
And the world that we know today
was resting on the shoulders
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00:19:24,400 --> 00:19:26,656
of creatures just like this rat.
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00:19:26,680 --> 00:19:28,120
I like that.
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00:19:29,520 --> 00:19:31,400
Yes, down to you!
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00:19:43,200 --> 00:19:45,576
It's thought the extreme
cold conditions
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00:19:45,600 --> 00:19:48,440
lasted for more than ten years.
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00:19:54,560 --> 00:19:58,656
But eventually the sky cleared,
236
00:19:58,680 --> 00:20:01,696
the sun shone down
237
00:20:01,720 --> 00:20:05,080
and life could begin
to make a recovery.
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00:20:14,560 --> 00:20:17,296
For more than 150 million years,
239
00:20:17,320 --> 00:20:22,000
the mammals had been living
in the shadows of the dinosaurs.
240
00:20:33,960 --> 00:20:37,280
But now a new chapter could begin.
241
00:20:43,400 --> 00:20:45,920
The age of mammals.
242
00:20:51,760 --> 00:20:54,656
And it would be
Earth's geological forces,
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00:20:54,680 --> 00:20:59,000
rather than an asteroid, that
would change the course of life.
244
00:21:16,120 --> 00:21:18,576
Deep within
the North Atlantic Ocean,
245
00:21:18,600 --> 00:21:21,896
thousands of hydrothermal
vents begin to release
246
00:21:21,920 --> 00:21:25,656
vast quantities of greenhouse gases,
247
00:21:25,680 --> 00:21:29,416
including methane,
248
00:21:29,440 --> 00:21:35,200
a gas around 25 times more
potent than carbon dioxide.
249
00:21:39,280 --> 00:21:41,536
THUNDERCLAP
250
00:21:41,560 --> 00:21:45,976
This methane escapes
into the atmosphere,
251
00:21:46,000 --> 00:21:50,560
sending temperatures rocketing
and triggering rapid climate change.
252
00:21:52,920 --> 00:21:57,120
Violent storms ravage the planet
with flash floods...
253
00:22:01,320 --> 00:22:03,320
..and protracted droughts.
254
00:22:07,080 --> 00:22:11,336
This dramatic global warming
has profound implications
255
00:22:11,360 --> 00:22:13,400
for the ancient mammals.
256
00:22:18,320 --> 00:22:20,880
BIRDS TWITTER
257
00:22:33,600 --> 00:22:34,640
Look.
258
00:22:36,280 --> 00:22:38,656
Millions of bats.
259
00:22:38,680 --> 00:22:41,240
Millions of mammals.
260
00:22:46,400 --> 00:22:49,016
I can smell them, I can see them,
261
00:22:49,040 --> 00:22:51,896
I can hear them and I can feel them.
262
00:22:51,920 --> 00:22:54,656
There are so many bats
out there whirling around
263
00:22:54,680 --> 00:22:56,936
that it's actually
generated a breeze,
264
00:22:56,960 --> 00:22:59,480
which is very pleasant
given how sweaty I am.
265
00:23:04,600 --> 00:23:07,296
And it's ironic, isn't it,
that, just when the planet
266
00:23:07,320 --> 00:23:09,816
was going to see the rise
of mammals,
267
00:23:09,840 --> 00:23:13,216
which would ultimately give rise
to species like our own,
268
00:23:13,240 --> 00:23:16,696
it was also going through
what can only be described as
269
00:23:16,720 --> 00:23:18,856
rapid climate change?
270
00:23:18,880 --> 00:23:22,176
And I can show you that
here with this graph.
271
00:23:22,200 --> 00:23:25,616
Now, the Earth was already a few
degrees warmer at this time,
272
00:23:25,640 --> 00:23:27,456
but look at this spike.
273
00:23:27,480 --> 00:23:30,096
What this tells us is that,
within the space of just
274
00:23:30,120 --> 00:23:34,896
a few thousand years,
the global average temperature rose
275
00:23:34,920 --> 00:23:37,096
by five degrees Centigrade.
276
00:23:37,120 --> 00:23:40,936
Incredible but sobering,
277
00:23:40,960 --> 00:23:44,736
because climate scientists today go
back through the geological record
278
00:23:44,760 --> 00:23:47,536
and they use this spike
as an analogue
279
00:23:47,560 --> 00:23:51,240
for what might be happening
to our atmosphere today.
280
00:23:52,360 --> 00:23:56,096
And what really concerns them
is how this happened.
281
00:23:56,120 --> 00:24:00,016
What's scary is that it was
precipitated by a series of events,
282
00:24:00,040 --> 00:24:03,376
each triggering the next, triggering
the next, triggering the next,
283
00:24:03,400 --> 00:24:08,576
until it pushed the Earth past
some serious tipping points.
284
00:24:08,600 --> 00:24:11,360
And that is our nightmare.
285
00:24:16,560 --> 00:24:20,216
Scientists believe that
56 million years ago
286
00:24:20,240 --> 00:24:24,840
the hot conditions on Earth
led to a very different world.
287
00:24:27,760 --> 00:24:33,456
In the Arctic, where temperatures
averaged around 23 degrees,
288
00:24:33,480 --> 00:24:37,760
alligators could be found
swimming under palm trees.
289
00:24:39,880 --> 00:24:43,776
But despite this havoc,
this hothouse Earth
290
00:24:43,800 --> 00:24:46,400
seems to have had a silver lining.
291
00:24:50,800 --> 00:24:53,856
Because, thanks to the
warmer conditions,
292
00:24:53,880 --> 00:24:59,536
subtropical forest or jungle
has moved away from the equator
293
00:24:59,560 --> 00:25:04,400
and expanded across much
of North America, Europe and Asia.
294
00:25:09,000 --> 00:25:13,736
And this rich, lush habitat
would prove to be crucial
295
00:25:13,760 --> 00:25:17,920
to the emergence of
new species of mammal.
296
00:25:19,160 --> 00:25:21,800
Ones more like us.
297
00:25:41,560 --> 00:25:43,496
Wow!
298
00:25:43,520 --> 00:25:45,696
Just look at that.
299
00:25:45,720 --> 00:25:47,360
What a landscape.
300
00:25:48,640 --> 00:25:52,576
This is the Calakmul Biosphere
Reserve in Mexico
301
00:25:52,600 --> 00:25:56,136
and, with its 2,700 square miles
of forest,
302
00:25:56,160 --> 00:25:59,816
it's one of the largest
forest reserves in Mexico
303
00:25:59,840 --> 00:26:01,936
and Latin America.
304
00:26:01,960 --> 00:26:05,336
And aside from these Mayan ruins
on which I'm standing
305
00:26:05,360 --> 00:26:08,656
and a few other pockets of
development, there's very little
306
00:26:08,680 --> 00:26:12,696
human activity here, which means
it's packed full of wildlife.
307
00:26:12,720 --> 00:26:15,936
More than 400 species of birds -
308
00:26:15,960 --> 00:26:20,080
toucans, trogons,
parrots and tanagers.
309
00:26:22,720 --> 00:26:24,536
And it's not just birds.
310
00:26:24,560 --> 00:26:28,776
Hiding in the forest here are all
sorts of other natural wonders -
311
00:26:28,800 --> 00:26:32,216
ocelot, puma, monkeys,
312
00:26:32,240 --> 00:26:34,056
enormous numbers of bats,
313
00:26:34,080 --> 00:26:36,416
not to mention a host of
reptiles and amphibians.
314
00:26:36,440 --> 00:26:42,240
So, the question is, why is this
place such a biodiversity hot spot?
315
00:26:48,880 --> 00:26:52,456
Now, it's partly due to the
vast diversity of plants
316
00:26:52,480 --> 00:26:53,856
that we have here.
317
00:26:53,880 --> 00:26:58,656
We think that in this area alone
there are more than 1,500 species.
318
00:26:58,680 --> 00:27:00,336
But it's not just that.
319
00:27:00,360 --> 00:27:03,376
It's also down to something that
we very much take for granted.
320
00:27:03,400 --> 00:27:06,696
Have a look at this fossil
that I've got here,
321
00:27:06,720 --> 00:27:11,776
and in particular
this tiny star-shaped structure.
322
00:27:11,800 --> 00:27:15,696
That is a fossilised flower.
323
00:27:15,720 --> 00:27:19,736
And we know from where this rock
came from, in Utah in North America,
324
00:27:19,760 --> 00:27:22,496
that that means that
this flower bloomed
325
00:27:22,520 --> 00:27:27,096
around 51 million years ago.
326
00:27:27,120 --> 00:27:29,360
That is incredible.
327
00:27:37,920 --> 00:27:43,360
Flowering plants are one of the
great drivers of biodiversity.
328
00:27:46,000 --> 00:27:50,136
And 56 million years ago,
Earth's flourishing forests
329
00:27:50,160 --> 00:27:51,840
were full of them.
330
00:27:56,920 --> 00:28:00,816
For insects, flowers offered
food in the form of nectar
331
00:28:00,840 --> 00:28:05,280
to tempt them in to spread the
plant's pollen for fertilisation.
332
00:28:13,040 --> 00:28:17,960
But for other creatures,
there was an even juicier prize.
333
00:28:20,920 --> 00:28:23,896
Something they can eat
that helps disperse
334
00:28:23,920 --> 00:28:26,520
the plant's fertilised seeds.
335
00:28:28,360 --> 00:28:32,280
One of the plant kingdom's
great gifts to life.
336
00:28:35,080 --> 00:28:36,320
Fruit.
337
00:28:43,600 --> 00:28:47,680
First eaten by birds many tens
of millions of years earlier...
338
00:28:49,200 --> 00:28:53,296
..the fruits of the forest were
to play a key role in the
339
00:28:53,320 --> 00:28:58,080
evolution of a new type of mammal
revealed in the fossil record.
340
00:29:01,920 --> 00:29:06,336
Fruit offered both a reward
and a challenge for mammals.
341
00:29:06,360 --> 00:29:09,656
Now, the reward is that this
is a perfectly formed capsule
342
00:29:09,680 --> 00:29:11,776
packed full of calories.
343
00:29:11,800 --> 00:29:14,096
The challenge is
you've got to find it
344
00:29:14,120 --> 00:29:17,856
and then you've got to be able to
get it, and in a forest environment
345
00:29:17,880 --> 00:29:20,936
like this
that's actually quite difficult.
346
00:29:20,960 --> 00:29:23,856
To find it,
you've got to be able to see it
347
00:29:23,880 --> 00:29:26,816
and then identify that it's ripe.
348
00:29:26,840 --> 00:29:30,056
And once you've done so,
you've got to be able to reach it,
349
00:29:30,080 --> 00:29:33,776
which means that you've got to be
able to climb all the way up there,
350
00:29:33,800 --> 00:29:36,856
20, 30 metres or more.
351
00:29:36,880 --> 00:29:40,216
So what creature could
have possibly evolved
352
00:29:40,240 --> 00:29:44,360
that could take advantage
of this fabulous resource?
353
00:29:46,480 --> 00:29:49,120
Maybe something like that.
354
00:29:51,160 --> 00:29:55,496
And that is a
Geoffroy's spider monkey.
355
00:29:55,520 --> 00:29:58,576
Quite a rare animal these days.
356
00:29:58,600 --> 00:30:02,376
But the key thing is that this
animal shares significant
357
00:30:02,400 --> 00:30:06,656
characteristics with those first
true primates that arose
358
00:30:06,680 --> 00:30:09,720
56 million years ago.
359
00:30:10,720 --> 00:30:13,256
Look at them, they're beautiful,
if not a little weird.
360
00:30:13,280 --> 00:30:15,816
They're highly specialised,
but look at the head.
361
00:30:15,840 --> 00:30:18,536
Their eyes are forward-facing,
like ours,
362
00:30:18,560 --> 00:30:21,776
good for stereoscopic vision,
good for spotting fruit.
363
00:30:21,800 --> 00:30:25,016
They've got a relatively big brain,
so they can remember where
364
00:30:25,040 --> 00:30:29,216
they previously found that fruit,
but the key thing are the limbs.
365
00:30:29,240 --> 00:30:32,616
Look - long and strong.
366
00:30:32,640 --> 00:30:35,216
And if you look very
carefully there,
367
00:30:35,240 --> 00:30:38,096
you can see their hands
are like hooks.
368
00:30:38,120 --> 00:30:41,296
And their fifth limb,
that prehensile tail,
369
00:30:41,320 --> 00:30:43,096
it's so strong they can hang from it
370
00:30:43,120 --> 00:30:45,160
when they're eating fruits
like this.
371
00:30:47,160 --> 00:30:51,816
There's no denying that creatures
like this are perfectly adapted
372
00:30:51,840 --> 00:30:56,000
for the high life up there
at the top of the forest.
373
00:31:04,280 --> 00:31:08,136
Now, we're not entirely sure where
the world's first true primates,
374
00:31:08,160 --> 00:31:11,336
our ancestors, appeared
because as soon as they evolved
375
00:31:11,360 --> 00:31:14,176
they started spreading rapidly
around the world,
376
00:31:14,200 --> 00:31:18,696
between North America and Asia
and on into Europe and Africa.
377
00:31:18,720 --> 00:31:22,136
These primates, they were having
the time of their lives,
378
00:31:22,160 --> 00:31:25,936
and very rapidly they'd
occupied no less than four
379
00:31:25,960 --> 00:31:27,496
of the world's continents.
380
00:31:27,520 --> 00:31:29,576
They were making it look easy
and at this point
381
00:31:29,600 --> 00:31:32,816
it seemed as if the Earth
was destined to become
382
00:31:32,840 --> 00:31:34,520
a planet of the apes.
383
00:31:39,440 --> 00:31:41,080
But it wasn't to be.
384
00:31:43,520 --> 00:31:47,680
After more than 20 million years
of a hothouse Earth...
385
00:31:56,800 --> 00:32:00,200
..the planet's climate
dramatically cooled.
386
00:32:05,560 --> 00:32:10,096
Scientists aren't entirely sure
why it happened,
387
00:32:10,120 --> 00:32:12,920
but the result was devastating.
388
00:32:16,840 --> 00:32:18,936
Across the northern continents,
389
00:32:18,960 --> 00:32:22,840
the cooler, drier conditions
decimated the jungle.
390
00:32:26,800 --> 00:32:31,240
Destroying much of the habitat
of our ancient ancestors.
391
00:32:39,840 --> 00:32:43,696
Sadly, we've been conducting
our own perverse experiment
392
00:32:43,720 --> 00:32:47,016
into what happens
if you deforest the planet.
393
00:32:47,040 --> 00:32:51,016
This is just one of a multitude
of sites all over the world
394
00:32:51,040 --> 00:32:53,056
that have been destroyed.
395
00:32:53,080 --> 00:32:57,256
Until recently, this would
have been tropical forest -
396
00:32:57,280 --> 00:33:02,096
lush, green,
filled with masses of mammals,
397
00:33:02,120 --> 00:33:05,976
monkeys, tapirs, jaguar.
398
00:33:06,000 --> 00:33:08,776
But they're all gone.
399
00:33:08,800 --> 00:33:11,456
You see, habitat destruction
like this
400
00:33:11,480 --> 00:33:16,056
is probably THE leading force
when it comes to extinction today,
401
00:33:16,080 --> 00:33:20,696
and it was no different
34 million years ago.
402
00:33:20,720 --> 00:33:24,096
When the tropical forest disappeared
from the northern climes,
403
00:33:24,120 --> 00:33:26,776
there were severe consequences.
404
00:33:26,800 --> 00:33:30,536
The primates disappeared from
North America completely
405
00:33:30,560 --> 00:33:33,456
and all but disappeared from Europe.
406
00:33:33,480 --> 00:33:37,496
So, on the face of it,
this looks like a massive tragedy,
407
00:33:37,520 --> 00:33:41,680
a severe setback for
our ancient ancestors.
408
00:33:43,520 --> 00:33:45,376
Or was it?
409
00:33:45,400 --> 00:33:50,416
Because, if the story that we're
really telling is the story of us,
410
00:33:50,440 --> 00:33:54,336
Homo sapiens, humans,
then it's not that simple.
411
00:33:54,360 --> 00:33:58,296
The path of evolution that would
lead from those ancient ancestors
412
00:33:58,320 --> 00:34:03,416
to a creature like us, an upright,
bipedal, big-brained ape
413
00:34:03,440 --> 00:34:07,296
with opposing thumbs, was never
going to be straight-forward.
414
00:34:07,320 --> 00:34:11,336
For evolution to come up with
something like the human species,
415
00:34:11,360 --> 00:34:16,016
it would require a very precise
and complex series of events,
416
00:34:16,040 --> 00:34:21,176
and it would need to occur
in a very specific environment,
417
00:34:21,200 --> 00:34:27,480
where evolution could be nudged, if
you like, towards the human species.
418
00:34:28,520 --> 00:34:33,480
And it would be down to the Earth
to create that very special place.
419
00:34:49,560 --> 00:34:53,096
Although primates had mostly
disappeared from the cold,
420
00:34:53,120 --> 00:34:55,400
dry, northerly continents...
421
00:35:00,000 --> 00:35:04,176
..in East Africa,
where the jungle still remained,
422
00:35:04,200 --> 00:35:05,880
they had survived.
423
00:35:13,920 --> 00:35:19,240
And here, the planet's forces
began to shape a new environment.
424
00:35:23,280 --> 00:35:28,056
From deep within Earth,
hot magma started to rise up,
425
00:35:28,080 --> 00:35:33,416
lifting the ground and forming
large cracks on the surface
426
00:35:33,440 --> 00:35:37,920
as, over millions of years,
the continent pulls apart.
427
00:35:58,000 --> 00:36:02,920
It forms the spectacular
East African Rift Valley.
428
00:36:04,720 --> 00:36:09,056
Running some 4,000 miles
through what will become
429
00:36:09,080 --> 00:36:14,000
Ethiopia, Kenya,
Tanzania and Mozambique.
430
00:36:20,640 --> 00:36:26,176
And crucially, with its patchwork
of forests and savannah,
431
00:36:26,200 --> 00:36:29,720
it presents the primates
with a dilemma.
432
00:36:31,520 --> 00:36:33,560
ENGINE PUTTERS
433
00:36:47,200 --> 00:36:49,976
So what was the dilemma?
434
00:36:50,000 --> 00:36:52,936
Well, the first thing you have
to appreciate is that the
435
00:36:52,960 --> 00:36:56,456
Rift Valley in East Africa was
no longer a single, great,
436
00:36:56,480 --> 00:36:58,656
vast tract of tropical forest.
437
00:36:58,680 --> 00:37:02,776
It had become fragmented
into smaller pockets of forest,
438
00:37:02,800 --> 00:37:06,936
quite analogous to this rather
beautiful park that I'm sat in.
439
00:37:06,960 --> 00:37:11,456
So these represent those pockets
of forest and the paths in-between
440
00:37:11,480 --> 00:37:14,736
the grassland that had
formed between them.
441
00:37:14,760 --> 00:37:19,136
Now, I want you to imagine
that you are a highly arboreal,
442
00:37:19,160 --> 00:37:22,496
tree swinging, fruit eating primate
443
00:37:22,520 --> 00:37:25,536
and you've had your breakfast
here at point A,
444
00:37:25,560 --> 00:37:29,400
but your lunch is over there
at point B.
445
00:37:30,600 --> 00:37:32,336
How do you get between the two?
446
00:37:32,360 --> 00:37:37,296
Because in the old days you could
simply swing from tree to tree.
447
00:37:37,320 --> 00:37:42,080
This was the dilemma
facing those early primates.
448
00:37:43,400 --> 00:37:46,896
The forest had fragmented,
so had their food supply,
449
00:37:46,920 --> 00:37:51,840
and they had no efficient way
of getting from A to B.
450
00:37:53,320 --> 00:37:56,016
So, what was the solution?
451
00:37:56,040 --> 00:37:58,096
What did evolution come up with?
452
00:37:58,120 --> 00:38:01,576
Well, some of those early primates
decided to stick it out in the
453
00:38:01,600 --> 00:38:05,416
shrinking forest and they evolved
into chimpanzees and gorillas.
454
00:38:05,440 --> 00:38:08,696
But another group,
our ancient ancestors,
455
00:38:08,720 --> 00:38:11,616
started to do something
that we take for granted
456
00:38:11,640 --> 00:38:14,456
but we have to learn to do.
457
00:38:14,480 --> 00:38:16,216
What do you reckon?
458
00:38:16,240 --> 00:38:19,600
I'll tell you -
they started walking on two feet.
459
00:38:33,600 --> 00:38:37,496
But our early ancestors didn't
just walk out of the forest
460
00:38:37,520 --> 00:38:40,416
never to return. They still
spent a lot of time there,
461
00:38:40,440 --> 00:38:42,176
probably even sleeping in the trees.
462
00:38:42,200 --> 00:38:44,896
But walking gave them freedom
463
00:38:44,920 --> 00:38:48,056
and with that freedom came
the ability to hunt,
464
00:38:48,080 --> 00:38:51,856
so they started eating meat and
then they evolved bigger brains.
465
00:38:51,880 --> 00:38:54,976
And that's why the Rift Valley
in East Africa
466
00:38:55,000 --> 00:38:57,616
is known as
the Cradle of Humanity.
467
00:38:57,640 --> 00:39:02,656
Now, initially, there were quite
a number of human species.
468
00:39:02,680 --> 00:39:05,816
But the key thing is that
that is where our species,
469
00:39:05,840 --> 00:39:07,960
Homo sapiens, evolved.
470
00:39:16,960 --> 00:39:22,160
Now, the origins of our species
are still shrouded in mystery.
471
00:39:31,720 --> 00:39:35,136
But the East African Rift Valley
is where scientists
472
00:39:35,160 --> 00:39:38,680
have discovered many of the
most important fossils...
473
00:39:43,080 --> 00:39:47,000
..that tell the incredible
story of human evolution...
474
00:39:51,000 --> 00:39:54,616
..and the emergence of Homo sapiens
475
00:39:54,640 --> 00:39:57,680
around 300,000 years ago.
476
00:40:08,520 --> 00:40:12,976
With hindsight, we simply have
to marvel at that remarkable
477
00:40:13,000 --> 00:40:17,856
set of factors that came together
to produce that highly unlikely
478
00:40:17,880 --> 00:40:19,856
chain of events.
479
00:40:19,880 --> 00:40:23,216
The seemingly impossible
had happened.
480
00:40:23,240 --> 00:40:25,976
After the best part
of 66 million years,
481
00:40:26,000 --> 00:40:28,936
after continents tearing
themselves apart,
482
00:40:28,960 --> 00:40:32,576
mountain ranges forming,
the Earth's climate fluxing
483
00:40:32,600 --> 00:40:34,616
and throwing between hot and cold,
484
00:40:34,640 --> 00:40:38,680
a new force was about to be
unleashed upon the Earth.
485
00:40:39,960 --> 00:40:43,160
Humans had arrived,
and there was no turning back.
486
00:41:19,400 --> 00:41:23,840
Yet whilst our species had been
evolving in the warmth of Africa...
487
00:41:25,920 --> 00:41:29,240
..Earth's climate
had continued to cool.
488
00:41:38,840 --> 00:41:42,576
Scientists think that part of the
reason may be down to Earth's
489
00:41:42,600 --> 00:41:45,256
new mountain ranges -
490
00:41:45,280 --> 00:41:48,480
the Himalayas, Andes and Rockies.
491
00:41:50,400 --> 00:41:53,496
They had formed over
tens of millions of years
492
00:41:53,520 --> 00:41:59,480
as the result of plate tectonics
pushing up the Earth's crust.
493
00:42:01,360 --> 00:42:03,776
And through the
process of weathering,
494
00:42:03,800 --> 00:42:07,416
the exposed rock was reacting
with carbon dioxide,
495
00:42:07,440 --> 00:42:11,800
removing it from the air
and causing temperatures to drop.
496
00:42:22,240 --> 00:42:27,376
It meant that, as humans migrated
out of Africa into Europe,
497
00:42:27,400 --> 00:42:32,936
Asia and Australia, the extreme
cold, dry conditions
498
00:42:32,960 --> 00:42:36,960
prevented them from crossing
into North America.
499
00:42:42,480 --> 00:42:46,240
Earth was in the midst
of an Ice Age.
500
00:43:03,120 --> 00:43:06,136
And yet, despite
the extreme challenges
501
00:43:06,160 --> 00:43:11,816
we faced from the climate,
it was around this time that humans
502
00:43:11,840 --> 00:43:16,960
began to create something that had
never existed on Earth before.
503
00:43:22,400 --> 00:43:23,920
Art.
504
00:43:30,200 --> 00:43:35,616
The oldest that we know of is this
painting of a pig in Indonesia,
505
00:43:35,640 --> 00:43:40,160
and it's been dated
to around 45,000 years ago.
506
00:43:53,520 --> 00:43:55,696
And closer to home in Europe,
507
00:43:55,720 --> 00:43:59,200
we find cave paintings
from more recent periods.
508
00:44:08,440 --> 00:44:11,736
Here we are,
back in this spectacular cave
509
00:44:11,760 --> 00:44:13,696
with its remarkable drawings.
510
00:44:13,720 --> 00:44:18,296
They are so, so beautiful that
it's worth taking a moment
511
00:44:18,320 --> 00:44:20,496
to think about what's going on here.
512
00:44:20,520 --> 00:44:24,736
Well, around 13,000 years ago,
513
00:44:24,760 --> 00:44:28,776
humans of the same species,
exactly the same species as us,
514
00:44:28,800 --> 00:44:34,256
were standing or crouching here in
the flickering light of their lamps,
515
00:44:34,280 --> 00:44:39,416
making these beautiful,
beautiful drawings.
516
00:44:39,440 --> 00:44:41,736
But what's it about?
517
00:44:41,760 --> 00:44:44,976
Well, art is always
about communication.
518
00:44:45,000 --> 00:44:49,096
And this isn't just communicating
to me about their intelligence
519
00:44:49,120 --> 00:44:52,896
or their creativity -
there's something else going on.
520
00:44:52,920 --> 00:44:57,216
And it's interesting to note that
in cave paintings of this age
521
00:44:57,240 --> 00:45:00,256
humans are very rarely depicted.
522
00:45:00,280 --> 00:45:03,856
It's always about nature.
523
00:45:03,880 --> 00:45:08,616
And at this time, all of these
species were wild animals.
524
00:45:08,640 --> 00:45:13,176
We were still hunter gatherers,
we were in tune with,
525
00:45:13,200 --> 00:45:17,520
connected to and, critically,
part of nature.
526
00:45:18,680 --> 00:45:22,776
But for us to go on to become the
global force that we've become,
527
00:45:22,800 --> 00:45:25,256
things would need to change.
528
00:45:25,280 --> 00:45:28,216
Our population would have
to grow massively
529
00:45:28,240 --> 00:45:32,920
and to achieve that
we would need to control nature.
530
00:45:47,480 --> 00:45:51,056
The extreme cold and dry
conditions of the Ice Age
531
00:45:51,080 --> 00:45:53,440
were not destined to last.
532
00:45:55,560 --> 00:45:59,616
Subtle changes in Earth's orbit
altered the amount of sunlight
533
00:45:59,640 --> 00:46:01,400
reaching the planet's surface.
534
00:46:02,800 --> 00:46:06,536
And together with increasing
levels of carbon dioxide,
535
00:46:06,560 --> 00:46:09,280
this pushed up temperatures...
536
00:46:13,440 --> 00:46:15,600
..melting the ice.
537
00:46:24,640 --> 00:46:29,440
For the first time, humans spread
across North and South America.
538
00:46:31,520 --> 00:46:36,240
We were now living on every
continent except Antarctica.
539
00:46:46,240 --> 00:46:49,056
And it was around 11,000 years ago,
540
00:46:49,080 --> 00:46:52,296
in this warmer and
more humid climate,
541
00:46:52,320 --> 00:46:56,920
that humans did something simple
but revolutionary.
542
00:46:58,680 --> 00:47:01,256
They began to farm,
543
00:47:01,280 --> 00:47:05,280
first growing crops,
then raising livestock.
544
00:47:07,000 --> 00:47:08,896
Within a few thousand years,
545
00:47:08,920 --> 00:47:13,480
nearly all human societies
on the planet were farming.
546
00:47:17,680 --> 00:47:20,456
And slowly but surely,
547
00:47:20,480 --> 00:47:25,216
producing food became
an industrialised process
548
00:47:25,240 --> 00:47:29,600
with an ever greater impact
on Earth's ecosystems.
549
00:47:48,560 --> 00:47:53,016
This is a vast field of soya beans,
550
00:47:53,040 --> 00:47:57,296
stretching all the way to the
horizon where the forest remains.
551
00:47:57,320 --> 00:48:00,896
And many people think of this
as a natural environment,
552
00:48:00,920 --> 00:48:04,456
but it couldn't be further
from natural if it tried.
553
00:48:04,480 --> 00:48:08,336
This is the antithesis
of biodiversity.
554
00:48:08,360 --> 00:48:11,776
Now, imagine biodiversity
is a rainbow
555
00:48:11,800 --> 00:48:16,176
and the spectrum represents the
full breadth of beautiful life
556
00:48:16,200 --> 00:48:18,376
and when we're looking at this
557
00:48:18,400 --> 00:48:21,536
we're looking at a tiny slice
of one colour.
558
00:48:21,560 --> 00:48:26,616
All of these regimented rows
here are just one species.
559
00:48:26,640 --> 00:48:28,560
This is a monoculture.
560
00:48:29,960 --> 00:48:33,776
And it's not just that because
the conditions that this crop
561
00:48:33,800 --> 00:48:36,416
require to grow
weren't here naturally.
562
00:48:36,440 --> 00:48:40,176
This has been flattened, it's been
drained, it's been fertilised.
563
00:48:40,200 --> 00:48:43,880
It's been smothered in pesticides
to keep nature out.
564
00:48:45,880 --> 00:48:48,656
Now, forgive me,
because for just a moment
565
00:48:48,680 --> 00:48:51,616
I'm going to take on the difficult
role of devil's advocate.
566
00:48:51,640 --> 00:48:55,136
Imagine that we could put
all of those environmental issues
567
00:48:55,160 --> 00:48:57,560
to one side
and take a fresh look at this.
568
00:49:03,800 --> 00:49:06,776
We might consider it
to be remarkable
569
00:49:06,800 --> 00:49:11,176
because it's highly efficient
crop production like this
570
00:49:11,200 --> 00:49:14,256
which is producing
enough food to cater
571
00:49:14,280 --> 00:49:18,296
for our ever increasing
human population.
572
00:49:18,320 --> 00:49:22,736
You might say that our ability
to invent technologies
573
00:49:22,760 --> 00:49:26,496
and come up with a food production
system that can feed
574
00:49:26,520 --> 00:49:29,816
around eight billion people
and keep many of them
575
00:49:29,840 --> 00:49:34,640
out of starvation and famine
is an incredible achievement.
576
00:49:36,160 --> 00:49:38,896
But I can't forget
those environmental issues,
577
00:49:38,920 --> 00:49:42,336
certainly when I tell you that 40%
578
00:49:42,360 --> 00:49:46,416
of the world's land surface
that isn't frozen
579
00:49:46,440 --> 00:49:50,496
is now given over to
agriculture like this -
580
00:49:50,520 --> 00:49:54,816
bland monocultures devoid of life.
581
00:49:54,840 --> 00:50:00,496
And also, I can tell you that, of
all the mammals alive at this point
582
00:50:00,520 --> 00:50:02,416
on planet Earth today,
583
00:50:02,440 --> 00:50:06,496
only 4% of them are wild animals.
584
00:50:06,520 --> 00:50:10,936
96% are humans, their pets
585
00:50:10,960 --> 00:50:12,920
or domestic farm animals.
586
00:50:14,840 --> 00:50:19,080
And that, from my perspective,
is terrifying.
587
00:50:29,360 --> 00:50:32,016
But our takeover
of the natural world
588
00:50:32,040 --> 00:50:34,360
goes far beyond
industrial agriculture.
589
00:50:39,320 --> 00:50:43,456
Humans now have a greater effect
in shaping the Earth's surface
590
00:50:43,480 --> 00:50:45,760
than many natural processes.
591
00:50:49,640 --> 00:50:53,616
And human-made materials,
like concrete and plastic,
592
00:50:53,640 --> 00:50:59,360
outweigh the combined biomass
of all life on the planet.
593
00:51:02,800 --> 00:51:08,216
Behind all of this is the staggering
increase in the human population.
594
00:51:08,240 --> 00:51:11,560
From one billion just
a couple of hundred years ago...
595
00:51:13,720 --> 00:51:16,240
..to eight billion today.
596
00:51:36,360 --> 00:51:39,440
Welcome to the human planet.
597
00:51:40,560 --> 00:51:45,816
Now, it is awesome
but for me it's not wondrous
598
00:51:45,840 --> 00:51:49,240
because, hand on heart,
this is not my sort of environment.
599
00:51:50,440 --> 00:51:53,056
I mean, there is some nature here,
600
00:51:53,080 --> 00:51:56,096
but most of it
is entirely artificial.
601
00:51:56,120 --> 00:52:01,640
Most of what I can see is made
of brick, concrete, steel and glass.
602
00:52:03,360 --> 00:52:06,016
This is Mexico City,
603
00:52:06,040 --> 00:52:10,856
and together with the 59 districts
that radiate out to the horizon
604
00:52:10,880 --> 00:52:15,056
it occupies 3,000 square miles,
605
00:52:15,080 --> 00:52:18,880
and it's home to more
than 21 million people.
606
00:52:20,080 --> 00:52:22,536
And, staggeringly, it's not unique.
607
00:52:22,560 --> 00:52:26,496
There are more than 30 other
megacities across the world
608
00:52:26,520 --> 00:52:28,960
with more than ten million
people living in them.
609
00:52:30,880 --> 00:52:35,896
But standing here looking at all
of this you've got to ask,
610
00:52:35,920 --> 00:52:38,696
"How can it possibly work?"
611
00:52:38,720 --> 00:52:41,616
One thing that we
have to acknowledge
612
00:52:41,640 --> 00:52:44,096
is that agricultural revolution,
613
00:52:44,120 --> 00:52:47,976
our ability to produce food
with brutal efficiency.
614
00:52:48,000 --> 00:52:52,280
That's what feeds all of us
living in these megacities.
615
00:52:53,440 --> 00:52:57,336
But there's another far more
important ingredient,
616
00:52:57,360 --> 00:53:00,856
something that was
formed by the Earth and life
617
00:53:00,880 --> 00:53:02,816
hundreds of millions of years ago,
618
00:53:02,840 --> 00:53:06,920
something that we've drilled
for and mined for.
619
00:53:08,080 --> 00:53:11,496
I'm talking about
coal, oil and gas -
620
00:53:11,520 --> 00:53:13,400
the fossil fuels.
621
00:53:15,000 --> 00:53:17,496
That's what's powered the technology
that's allowed us
622
00:53:17,520 --> 00:53:20,776
to build these megacities.
623
00:53:20,800 --> 00:53:23,336
But it comes at a terrible cost
624
00:53:23,360 --> 00:53:26,216
because, as we continue to
burn those fossil fuels,
625
00:53:26,240 --> 00:53:29,896
we are pumping CO2
into this atmosphere
626
00:53:29,920 --> 00:53:33,616
at a rate that's comparable with
some of those volcanic eruptions
627
00:53:33,640 --> 00:53:36,040
that occurred millions of years ago.
628
00:53:37,760 --> 00:53:39,280
And critically...
629
00:53:41,240 --> 00:53:46,160
..we've started to radically
transform our climate.
630
00:53:58,120 --> 00:54:04,096
For most of Earth's
4.5 billion year history,
631
00:54:04,120 --> 00:54:06,920
the most dramatic changes
in climate...
632
00:54:10,640 --> 00:54:13,440
..have been driven by asteroids...
633
00:54:15,160 --> 00:54:17,120
LOUD BLAST
634
00:54:21,240 --> 00:54:23,600
LOUD RUMBLING
635
00:54:25,680 --> 00:54:29,320
..the powerful tectonic
movement of the continents...
636
00:54:38,080 --> 00:54:42,296
..and the catastrophic
eruptions of volcanoes.
637
00:54:42,320 --> 00:54:45,160
BOOMING EXPLOSION
638
00:55:04,400 --> 00:55:07,496
Of course, as we've seen,
639
00:55:07,520 --> 00:55:12,880
there have been moments when life
too has had a profound impact.
640
00:55:18,800 --> 00:55:26,280
Like the bacteria that colonised
the oceans 2.4 billion years ago...
641
00:55:28,400 --> 00:55:32,360
..and gave us the oxygen we breathe.
642
00:55:36,960 --> 00:55:42,496
Or the swamp forests that sent
temperatures spiralling downwards
643
00:55:42,520 --> 00:55:46,520
and created the coal we now burn.
644
00:55:53,920 --> 00:55:59,360
But today, the climate is
changing at a faster rate...
645
00:56:00,960 --> 00:56:06,040
..than at any time
in the last 66 million years.
646
00:56:12,560 --> 00:56:16,736
Now, I've seen so much of
the natural world that I cherish
647
00:56:16,760 --> 00:56:19,896
destroyed that it's difficult
not to be pessimistic.
648
00:56:19,920 --> 00:56:23,216
But, ironically,
when I go searching for hope,
649
00:56:23,240 --> 00:56:27,016
I don't turn to those
planetary forces.
650
00:56:27,040 --> 00:56:30,856
I turn to the power of humanity
651
00:56:30,880 --> 00:56:34,776
because, for all of our flaws,
all of our foolishness,
652
00:56:34,800 --> 00:56:38,560
we are a truly remarkable species.
653
00:56:40,000 --> 00:56:42,296
Adaptable, resourceful,
654
00:56:42,320 --> 00:56:45,240
inventive, intelligent, creative.
655
00:56:46,280 --> 00:56:50,336
And you might argue that our most
significant turning points
656
00:56:50,360 --> 00:56:54,056
were perhaps standing up on two legs
and beginning to walk
657
00:56:54,080 --> 00:56:58,096
or drawing those animals on the
cave walls or inventing farming,
658
00:56:58,120 --> 00:57:00,080
or even landing on the moon.
659
00:57:01,480 --> 00:57:07,216
But I need to argue that these
were just our dress rehearsals,
660
00:57:07,240 --> 00:57:11,416
because in the very near future
our species will need to reach
661
00:57:11,440 --> 00:57:16,856
the zenith of its achievements and
that all humanity will have to learn
662
00:57:16,880 --> 00:57:20,520
to put our Earth first.
663
00:57:22,160 --> 00:57:27,496
That unique, fragile,
beautiful Earth
664
00:57:27,520 --> 00:57:32,576
that for more than four billion
years has been forming this stage
665
00:57:32,600 --> 00:57:34,656
on which we now stand,
666
00:57:34,680 --> 00:57:38,080
and it's waiting for
our finest performance.
667
00:57:39,640 --> 00:57:41,656
And if we don't pull it off,
668
00:57:41,680 --> 00:57:46,416
then of course life on this planet
will continue to prosper.
669
00:57:46,440 --> 00:57:50,000
But there will be no
encore for humanity.
670
00:58:23,920 --> 00:58:27,176
If the Earth could talk,
what would it tell us?
671
00:58:27,200 --> 00:58:29,856
Well, the Open University
imagine how it might answer
672
00:58:29,880 --> 00:58:31,336
some of our questions.
673
00:58:31,360 --> 00:58:34,016
To experience this
interactive presentation,
674
00:58:34,040 --> 00:58:35,696
go to the website on the screen
675
00:58:35,720 --> 00:58:38,040
and follow the links
to the Open University.
676
00:58:38,090 --> 00:58:42,640
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