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[calm music playing]
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[Freeman] Every year
for just a few short months…
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[birds squawking]
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…fresh water flows
into the Okavango Delta…
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creating the perfect home…
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for a small family of elephants…
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and a playground
for their two young calves…
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Bosigo…
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[calf whines]
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…and her baby cousin, Metsi.
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[whining continues]
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[elephant trumpeting]
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[Freeman] Bosigo and Metsi
are only just beginning
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their love affair with water.
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[calm music swells]
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But from now on,
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their lives will be defined by it.
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[whooshing, crackling]
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This one precious molecule…
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[intense music playing]
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…delivered to Earth…
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[exploding]
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…by the astonishing forces
at work in our universe.
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[rumbling]
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It has transformed this planet…
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[whooshing]
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…into a haven…
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[sizzling]
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…for life.
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[dramatic music playing]
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[tense music playing]
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Summer has arrived.
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And what was paradise is no more.
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The fresh water that flooded the delta…
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only stays for a few months.
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And water holes are now vanishing.
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[crackling]
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Fast.
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This means only one thing
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for the thousands of elephants
who've been living here.
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[elephant trumpeting]
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It's time to move on.
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[pensive music playing]
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[elephant grumbling]
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[elephant trumpeting]
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This has been the only home
Metsi and Bosigo have ever known.
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[Metsi whines]
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But in a few weeks,
all the water will be gone.
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[Metsi grunts]
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So they must leave the delta
with the rest of their family.
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A herd of females,
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sisters, aunts, and cousins,
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led by their grandmother,
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the great matriarch, Pula.
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[pensive music continues]
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They're embarking on a journey
along with thousands of other families…
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out into the desert…
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in search of water.
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[whooshing]
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[intriguing music playing]
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For the next eight months,
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they will migrate
from water hole to water hole…
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and navigate ancient elephant trails…
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[elephant growls]
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…using the matriarch Pula's knowledge,
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handed down to her through generations.
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[zebras yelping]
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The trek will put all their lives at risk.
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[calf whining]
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And they'll need
every one of their exceptional senses…
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-[elephant trumpets]
-…to endure the dangers.
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[solemn music playing]
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Making this journey is not a choice.
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Without water, they will die.
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Even on our blue planet,
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fresh liquid water is scarce.
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And if we search beyond the shores
of our own planet…
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it's rarer still.
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Even the most arid desert on Earth
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is nothing compared
to the rest of our solar system.
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[pensive music playing]
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In the cold outer reaches…
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[whooshing]
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…the only surface water is ice.
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Like Saturn's frozen moons…
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where fountains of ice
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shoot kilometers into space.
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[whooshing]
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[ethereal tinkling]
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Closer to the Sun on Mars,
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water is stripped away
by savage solar winds.
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[wind gusting]
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[whooshing]
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[rumbling]
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And on Venus,
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it simply boils away.
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There's only one world we know of
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that has the gift
of liquid water on its surface.
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[majestic music playing]
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A pale blue dot.
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Our home…
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where right now,
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water is driving one particular family
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on a quest for survival.
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[majestic music crescendos]
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Just a month after leaving the delta,
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only a scattering of muddy pools remain.
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[solemn music playing]
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And they're getting fewer
and farther apart each day.
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Pula is using her highly tuned memory
to lead her family to a water hole.
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[Pula screeching]
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She can remember the exact route,
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even decades later.
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[elephant grumbling]
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It's been a long day's march,
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and all of them are desperate for a drink.
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[calf whining]
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[elephant trumpeting]
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But so are the other 130,000 elephants
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that live in Botswana.
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[playful music playing]
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[elephant trumpeting]
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[calf purring]
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[elephant grumbling]
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The dry season has drawn herds
from far and wide…
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[elephants roaring, trumpeting]
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…to this water hole.
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[calf roars softly]
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All competing
for the same shrinking resource.
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[elephants breathing heavily]
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[elephant growling]
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[trumpets]
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[calm music playing]
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[Metsi trumpeting]
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The adults teach the young ones
clever survival tricks,
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like how to skim a muddy pool
to get the freshest water.
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And how to use some muddy water
as refreshing sunscreen.
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Their wrinkly skin is perfect
for trapping water and keeping cool.
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[Metsi trumpets]
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But Metsi and Bosigo are also learning…
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mud pools aren't just a place to drink.
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They're water parks too.
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[calm music continues]
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[Bosigo purring]
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With so many thirsty elephants,
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the water hole has been drained.
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[elephant moaning]
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Pula's family must press on…
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and try to make it to the next water hole
before the blazing sun sucks it dry.
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[solemn music playing]
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This battle between sun and scorched earth
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has raged ever since our world was born…
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when our blue planet
was anything but blue.
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[tense music playing]
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00:11:04,160 --> 00:11:06,840
Four and a half billion years ago…
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Earth was in its infancy.
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A fireball of molten rock…
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[rumbling]
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…destined to become a dry, barren world.
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[tense music continues]
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00:11:31,440 --> 00:11:34,560
But millions of kilometers
out in the coldest reaches
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00:11:34,640 --> 00:11:35,880
of the solar system…
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water crystals were forming
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on the surface of dust particles.
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[crackling]
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[pensive music playing]
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Over time, these grains
of dust clumped together into asteroids.
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Millions and millions of them.
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00:12:06,080 --> 00:12:09,600
And these became the asteroid belt.
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A vast expanse of icy rocks.
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Yet they've laid tantalizingly out
of Earth's reach.
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As luck would have it, however,
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a giant was on the move.
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[tense music playing]
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Young Jupiter.
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A monster of a planet.
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00:12:48,080 --> 00:12:50,920
Forces within
the turbulent inner solar system
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00:12:51,640 --> 00:12:55,520
were slowly pulling it in toward the Sun.
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00:13:00,760 --> 00:13:03,880
A flight path that brought it
into a collision course
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00:13:04,760 --> 00:13:06,440
with the asteroid belt.
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[crashing]
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00:13:13,680 --> 00:13:16,080
[tense music continues]
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00:13:22,080 --> 00:13:24,560
As it thundered through the asteroids…
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[crashing, rumbling]
185
00:13:28,480 --> 00:13:30,800
…its massive gravitational force
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flung rocks in every direction.
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00:13:34,080 --> 00:13:36,800
[tense music continues]
188
00:13:41,880 --> 00:13:46,160
And yet,
from all this chaos and destruction
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00:13:46,240 --> 00:13:49,040
came the ultimate cosmic gift.
190
00:13:49,120 --> 00:13:50,880
[tense music crescendos]
191
00:13:52,880 --> 00:13:55,040
[ethereal music playing]
192
00:13:55,120 --> 00:14:00,760
Icy, water-rich rocks
were hurled towards the Earth…
193
00:14:02,160 --> 00:14:06,280
[elephants trumpeting]
194
00:14:06,360 --> 00:14:11,360
…bringing the promise of life
one step closer.
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00:14:15,720 --> 00:14:17,280
Over billions of years,
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00:14:17,360 --> 00:14:21,480
asteroids were woven
into the fabric of Earth as it formed.
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00:14:25,680 --> 00:14:29,240
Caught in the turmoil wrought by Jupiter…
198
00:14:29,320 --> 00:14:30,840
[dramatic music playing]
199
00:14:30,920 --> 00:14:34,120
…driven deep into the Earth by asteroids,
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00:14:35,800 --> 00:14:39,800
water molecules did not have
an easy journey getting here.
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[exploding]
202
00:14:42,760 --> 00:14:45,160
And they still had a long way to go,
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00:14:46,320 --> 00:14:49,320
imprisoned for millions of years,
204
00:14:50,200 --> 00:14:52,640
locked within Earth's molten core…
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00:14:55,640 --> 00:14:57,400
waiting for another miracle…
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00:15:00,600 --> 00:15:01,960
to set them free.
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00:15:12,040 --> 00:15:15,960
Today, much of Earth's water
is still trapped underground.
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00:15:19,600 --> 00:15:21,080
[intriguing music playing]
209
00:15:21,160 --> 00:15:22,800
[elephants trumpeting]
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00:15:23,880 --> 00:15:28,120
So elephants have evolved special skills
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00:15:28,200 --> 00:15:29,240
to find it.
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[elephant moaning]
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00:15:32,600 --> 00:15:34,680
[snorting]
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00:15:39,400 --> 00:15:41,960
Even the muddy pools are empty.
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00:15:43,240 --> 00:15:46,120
This dry season
has become a full-on drought.
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00:15:49,560 --> 00:15:51,880
But Pula has a superpower.
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00:15:51,960 --> 00:15:53,440
[Pula roaring]
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00:15:54,200 --> 00:15:55,720
Her incredible trunk,
219
00:15:57,240 --> 00:15:59,880
packed with millions of sense receptors…
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00:16:02,000 --> 00:16:04,440
can smell water from kilometers away…
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00:16:09,040 --> 00:16:12,880
and pinpoint its sources deep underground.
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00:16:12,960 --> 00:16:15,680
[Pula snorting]
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00:16:23,720 --> 00:16:25,080
But you have to dig for it.
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00:16:25,160 --> 00:16:26,160
[Pula snorts]
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00:16:27,080 --> 00:16:28,320
[grumbles]
226
00:16:33,880 --> 00:16:35,640
Metsi isn't a big digger.
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00:16:35,720 --> 00:16:37,080
[Metsi trumpets]
228
00:16:40,840 --> 00:16:43,080
But Bosigo is a natural.
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00:16:51,520 --> 00:16:54,680
And Metsi is offered a seat at the bar.
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00:17:00,360 --> 00:17:02,640
These few sips won't last them long.
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00:17:02,720 --> 00:17:05,240
[mysterious music playing]
232
00:17:05,320 --> 00:17:06,400
[Metsi whining]
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00:17:07,280 --> 00:17:09,880
But if water
had stayed trapped in the Earth,
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00:17:11,520 --> 00:17:13,240
there would be none to drink.
235
00:17:17,800 --> 00:17:19,680
There would be no elephants.
236
00:17:23,200 --> 00:17:25,280
No life at all.
237
00:17:27,920 --> 00:17:29,400
[whooshing]
238
00:17:31,600 --> 00:17:34,000
[mysterious music continues]
239
00:17:36,440 --> 00:17:37,720
[crashing, rumbling]
240
00:17:37,800 --> 00:17:41,160
After water
was delivered here by asteroids
241
00:17:41,240 --> 00:17:43,480
and consumed by the Earth…
242
00:17:45,640 --> 00:17:48,280
it was locked into the rock as crystals
243
00:17:50,200 --> 00:17:51,800
deep inside the planet.
244
00:17:51,880 --> 00:17:54,840
[tense music playing]
245
00:17:57,560 --> 00:18:00,160
It stayed buried for millions of years,
246
00:18:01,160 --> 00:18:04,360
beneath a vast sea of magma.
247
00:18:04,880 --> 00:18:07,280
[crackling]
248
00:18:11,880 --> 00:18:12,840
[sizzling]
249
00:18:12,920 --> 00:18:17,880
Until slowly but surely, Earth cooled.
250
00:18:21,360 --> 00:18:25,880
And its surface hardened to a thick crust.
251
00:18:26,480 --> 00:18:28,520
[whooshing]
252
00:18:29,680 --> 00:18:34,240
Then, finally,
the boiling interior broke through.
253
00:18:35,760 --> 00:18:37,600
[explosion rumbles]
254
00:18:41,440 --> 00:18:42,640
[thunder crashing]
255
00:18:43,720 --> 00:18:45,600
Enormous volcanoes
256
00:18:47,080 --> 00:18:50,880
blasted gas and vapor
kilometers into the sky.
257
00:18:53,280 --> 00:18:54,600
[exploding]
258
00:18:58,720 --> 00:19:01,520
At last, water molecules…
259
00:19:01,600 --> 00:19:02,920
[exploding]
260
00:19:03,000 --> 00:19:04,200
…were set free…
261
00:19:05,960 --> 00:19:07,080
[exploding]
262
00:19:11,080 --> 00:19:13,800
…and formed the first clouds.
263
00:19:13,880 --> 00:19:16,920
[energetic music playing]
264
00:19:18,480 --> 00:19:21,080
Growing and building
for millions of years,
265
00:19:21,600 --> 00:19:23,400
becoming laden with water…
266
00:19:24,040 --> 00:19:25,880
[wind howling]
267
00:19:25,960 --> 00:19:27,120
[thunder crashes]
268
00:19:28,320 --> 00:19:31,120
…until the temperature
dropped just enough…
269
00:19:31,640 --> 00:19:34,080
[thunder crashing]
270
00:19:38,920 --> 00:19:41,480
…for the very first raindrop…
271
00:19:41,560 --> 00:19:44,520
[ethereal tinkling]
272
00:19:46,920 --> 00:19:50,560
…to form and fall.
273
00:19:50,640 --> 00:19:53,400
[ethereal music playing]
274
00:19:57,320 --> 00:19:59,600
[sizzling]
275
00:20:00,200 --> 00:20:03,600
[raindrops pattering, sizzling]
276
00:20:03,680 --> 00:20:06,440
[dramatic music playing]
277
00:20:08,800 --> 00:20:11,000
What followed was a deluge…
278
00:20:16,240 --> 00:20:18,640
that lasted thousands of years.
279
00:20:30,040 --> 00:20:32,080
Puddles turned into rivers.
280
00:20:39,880 --> 00:20:41,440
[wind whistling]
281
00:20:41,520 --> 00:20:42,720
Lakes…
282
00:20:42,800 --> 00:20:44,320
[thunder rumbles]
283
00:20:44,400 --> 00:20:45,760
…became seas.
284
00:20:46,800 --> 00:20:49,240
[dramatic music continues]
285
00:20:53,480 --> 00:20:57,560
And great oceans flooded Earth's surface.
286
00:21:15,920 --> 00:21:20,120
And here, water gave rise
to something magical.
287
00:21:21,000 --> 00:21:22,680
-[gurgles]
-[ethereal tinkling]
288
00:21:25,320 --> 00:21:26,840
The first life.
289
00:21:28,600 --> 00:21:31,000
[ethereal tinkling continues]
290
00:21:31,080 --> 00:21:33,680
From these first cells
291
00:21:35,000 --> 00:21:38,040
sprang every living thing.
292
00:21:40,640 --> 00:21:43,960
Water is the fundamental ingredient
293
00:21:44,040 --> 00:21:48,000
of every cell of every creature on Earth.
294
00:21:48,080 --> 00:21:51,240
[dramatic music continues]
295
00:21:57,360 --> 00:21:58,440
And today…
296
00:22:01,320 --> 00:22:06,400
the herd still carries
this ancient water within them.
297
00:22:06,920 --> 00:22:07,800
[elephant snorts]
298
00:22:07,880 --> 00:22:10,200
[intriguing music playing]
299
00:22:12,080 --> 00:22:13,480
[elephant grumbles]
300
00:22:13,560 --> 00:22:16,480
[ethereal tinkling, whooshing]
301
00:22:18,040 --> 00:22:20,240
It transports nutrients and oxygen.
302
00:22:20,320 --> 00:22:22,680
[intriguing music continues]
303
00:22:22,760 --> 00:22:24,640
-[whooshing]
-[elephant trumpets]
304
00:22:24,720 --> 00:22:27,080
[grumbling]
305
00:22:27,640 --> 00:22:29,400
[whooshing]
306
00:22:30,200 --> 00:22:32,000
It powers every heartbeat.
307
00:22:32,080 --> 00:22:34,280
[heartbeat thumping]
308
00:22:35,240 --> 00:22:37,000
[elephant roars]
309
00:22:37,080 --> 00:22:38,840
[whooshing]
310
00:22:38,920 --> 00:22:41,160
And drives every breath.
311
00:22:41,240 --> 00:22:43,000
[breathing heavily]
312
00:22:46,640 --> 00:22:49,240
Life evolved because of water,
313
00:22:51,000 --> 00:22:54,960
which is why no life
can survive without it.
314
00:22:56,000 --> 00:22:58,280
[wind gusting]
315
00:22:58,360 --> 00:23:00,760
[solemn music playing]
316
00:23:01,920 --> 00:23:05,480
In Botswana,
the drought is only getting worse.
317
00:23:06,360 --> 00:23:08,080
[fire crackling]
318
00:23:11,080 --> 00:23:13,880
The elephants' world is on fire.
319
00:23:15,920 --> 00:23:17,160
[elephant grumbles]
320
00:23:19,400 --> 00:23:20,560
[trumpets]
321
00:23:22,600 --> 00:23:25,520
The herd manages
to escape the burning forest…
322
00:23:29,040 --> 00:23:31,320
but walks straight into a new threat.
323
00:23:31,400 --> 00:23:32,560
[elephant huffs]
324
00:23:34,240 --> 00:23:36,000
[lion growling]
325
00:23:37,560 --> 00:23:40,360
In this drought, everyone is suffering…
326
00:23:40,440 --> 00:23:41,720
[lion continues growling]
327
00:23:43,680 --> 00:23:46,160
…from thirst and hunger.
328
00:23:49,680 --> 00:23:52,520
[elephant grumbling]
329
00:23:52,600 --> 00:23:56,960
And for lions,
baby elephants would satisfy both.
330
00:24:00,000 --> 00:24:02,400
[ominous music playing]
331
00:24:04,320 --> 00:24:06,480
[Metsi trumpeting softly]
332
00:24:11,200 --> 00:24:12,640
[lion growls]
333
00:24:14,200 --> 00:24:17,320
The adults rally around Metsi and Bosigo.
334
00:24:23,360 --> 00:24:24,640
[lion growling]
335
00:24:24,720 --> 00:24:26,960
It's enough to keep the threat at bay.
336
00:24:27,040 --> 00:24:29,480
[growling continues]
337
00:24:30,680 --> 00:24:32,880
But lions are patient creatures.
338
00:24:36,880 --> 00:24:40,400
And the herd still has to cross
an unforgiving wasteland…
339
00:24:42,600 --> 00:24:44,280
before the next water hole.
340
00:24:45,680 --> 00:24:48,440
[wind gusting]
341
00:24:48,520 --> 00:24:50,680
They need a lifeline.
342
00:24:50,760 --> 00:24:52,840
[calm music playing]
343
00:24:53,760 --> 00:24:56,040
And the Earth provides it
344
00:24:57,720 --> 00:25:00,120
in the most unexpected of places.
345
00:25:03,840 --> 00:25:05,240
[birds chirping]
346
00:25:05,320 --> 00:25:08,000
The acacia tree is a beacon of hope.
347
00:25:13,880 --> 00:25:16,800
And a haven for creatures of all kinds.
348
00:25:18,320 --> 00:25:21,000
[calm music continues]
349
00:25:24,880 --> 00:25:28,320
Its long roots reach
much deeper underground
350
00:25:28,400 --> 00:25:30,400
than an elephant could ever dig…
351
00:25:30,480 --> 00:25:32,680
[crackling softly]
352
00:25:41,240 --> 00:25:43,360
…drawing water up to its branches…
353
00:25:47,360 --> 00:25:48,520
and leaves.
354
00:25:59,560 --> 00:26:00,920
[elephant trumpeting]
355
00:26:01,000 --> 00:26:04,480
It's just enough water to keep them going.
356
00:26:06,040 --> 00:26:08,200
[elephant grumbling]
357
00:26:08,280 --> 00:26:10,840
Especially vital for Metsi's mother,
358
00:26:12,720 --> 00:26:14,320
still nursing her baby.
359
00:26:18,320 --> 00:26:21,800
But this is so much more
than just a local oasis.
360
00:26:25,360 --> 00:26:28,480
It's the vital link
in water's eternal cycle.
361
00:26:28,560 --> 00:26:30,520
[elephant grumbling]
362
00:26:32,720 --> 00:26:36,800
The acacia tree connects ground and sky…
363
00:26:37,320 --> 00:26:39,520
[whooshing softly]
364
00:26:39,600 --> 00:26:41,320
[intriguing music playing]
365
00:26:43,600 --> 00:26:46,080
…breathing oxygen and vapor into the air.
366
00:26:48,560 --> 00:26:50,920
[whooshing softly]
367
00:26:53,480 --> 00:26:54,920
[thunder crashes]
368
00:26:55,000 --> 00:26:56,480
Feeding clouds
369
00:26:56,560 --> 00:26:59,320
and powering water's journey
around the planet.
370
00:26:59,400 --> 00:27:01,040
[wind gusting]
371
00:27:01,120 --> 00:27:03,480
[ethereal tinkling]
372
00:27:04,760 --> 00:27:06,480
[sizzling]
373
00:27:07,400 --> 00:27:08,880
Ever since rain
374
00:27:10,120 --> 00:27:12,400
fed the first green shoots…
375
00:27:16,320 --> 00:27:18,840
and gave life to the first tree…
376
00:27:21,800 --> 00:27:24,040
[birds chirping]
377
00:27:24,120 --> 00:27:27,720
…plants have made our planet habitable…
378
00:27:28,920 --> 00:27:31,200
[majestic music playing]
379
00:27:35,280 --> 00:27:37,680
…bringing a once barren ball of rock
380
00:27:39,440 --> 00:27:40,280
to life.
381
00:27:45,880 --> 00:27:48,760
But the gifts our universe bestows
382
00:27:50,320 --> 00:27:52,760
can also be taken away.
383
00:27:52,840 --> 00:27:55,400
[solemn music playing]
384
00:28:01,280 --> 00:28:02,760
A long time ago,
385
00:28:04,080 --> 00:28:05,680
there was another planet
386
00:28:06,680 --> 00:28:09,480
whose surface was covered in liquid water.
387
00:28:18,080 --> 00:28:20,600
A water world just like ours.
388
00:28:22,680 --> 00:28:25,040
[solemn music continues]
389
00:28:25,720 --> 00:28:28,440
The same forces
that delivered water to Earth
390
00:28:29,440 --> 00:28:32,000
also gave it to Mars.
391
00:28:35,200 --> 00:28:37,440
With an atmosphere in place,
392
00:28:37,520 --> 00:28:38,640
clouds formed,
393
00:28:40,480 --> 00:28:41,480
rain fell,
394
00:28:43,000 --> 00:28:44,440
rivers flowed.
395
00:28:45,000 --> 00:28:47,480
[calm music playing]
396
00:28:48,800 --> 00:28:52,160
And an ocean surged across its surface.
397
00:28:57,240 --> 00:28:59,520
It was a world of possibility.
398
00:29:00,040 --> 00:29:02,320
It had the potential for life.
399
00:29:06,600 --> 00:29:08,080
But it didn't last.
400
00:29:13,720 --> 00:29:19,080
Because not far away
was a raging nuclear inferno.
401
00:29:19,600 --> 00:29:20,960
[fire roaring]
402
00:29:21,040 --> 00:29:22,040
Our Sun.
403
00:29:24,120 --> 00:29:27,520
It unleashes torrents
of high-energy particles
404
00:29:27,600 --> 00:29:29,800
so powerful and deadly…
405
00:29:29,880 --> 00:29:32,400
[fire continues roaring]
406
00:29:32,480 --> 00:29:34,480
…they can devastate planets.
407
00:29:35,920 --> 00:29:38,400
[solemn music playing]
408
00:29:42,840 --> 00:29:43,880
[wind gusting]
409
00:29:43,960 --> 00:29:47,840
This solar wind streams through space…
410
00:29:52,320 --> 00:29:55,640
at 400 kilometers per second.
411
00:29:57,680 --> 00:29:58,880
[whooshing loudly]
412
00:30:00,480 --> 00:30:03,160
And it ripped through
the Martian atmosphere,
413
00:30:04,640 --> 00:30:06,800
tearing water molecules apart.
414
00:30:15,040 --> 00:30:16,520
Bit by bit,
415
00:30:16,600 --> 00:30:18,160
over millions of years,
416
00:30:19,600 --> 00:30:24,480
the planet's protective layer
was stripped away by the Sun's fury…
417
00:30:24,560 --> 00:30:26,680
[solemn music playing]
418
00:30:29,680 --> 00:30:31,640
…until its ocean evaporated…
419
00:30:37,640 --> 00:30:41,040
and its water was lost to space.
420
00:30:43,480 --> 00:30:46,000
[solemn music continues]
421
00:30:48,600 --> 00:30:52,400
Mars became a desolate, frozen shadow
422
00:30:52,920 --> 00:30:54,280
of its former self.
423
00:30:58,800 --> 00:31:00,480
[thunder crashes]
424
00:31:00,560 --> 00:31:02,680
[wind gusting]
425
00:31:03,360 --> 00:31:05,920
Consumed by dust storms.
426
00:31:12,520 --> 00:31:14,480
Any chance of complex life…
427
00:31:16,480 --> 00:31:18,280
gone forever.
428
00:31:19,480 --> 00:31:22,280
[wind continues gusting]
429
00:31:27,560 --> 00:31:29,640
This could have been our story too.
430
00:31:29,720 --> 00:31:32,080
[solemn music continues]
431
00:31:33,200 --> 00:31:35,680
[elephant grumbling]
432
00:31:37,080 --> 00:31:38,440
[trumpeting]
433
00:31:44,360 --> 00:31:46,640
But somehow, on Earth,
434
00:31:47,560 --> 00:31:51,280
water and life
have found a way to cling on.
435
00:31:51,360 --> 00:31:52,600
[elephant moaning]
436
00:32:06,320 --> 00:32:07,960
In Botswana,
437
00:32:08,040 --> 00:32:10,640
after 200 days in the burning sun…
438
00:32:11,160 --> 00:32:12,760
[wind gusting]
439
00:32:12,840 --> 00:32:15,000
…there is no water to be found.
440
00:32:19,000 --> 00:32:20,240
[solemn music continues]
441
00:32:20,320 --> 00:32:23,600
[elephants howling]
442
00:32:23,680 --> 00:32:26,040
Violent winds whip the scorched earth
443
00:32:26,120 --> 00:32:27,600
into a dust bowl.
444
00:32:33,160 --> 00:32:35,520
[wind continues gusting]
445
00:32:42,280 --> 00:32:43,280
[elephant huffs]
446
00:32:45,320 --> 00:32:49,440
And the elephants' struggle
hasn't gone unnoticed.
447
00:32:49,520 --> 00:32:52,200
[ominous music playing]
448
00:33:02,920 --> 00:33:06,800
In daylight,
adults can usually protect their young.
449
00:33:13,680 --> 00:33:15,720
[elephants moaning]
450
00:33:18,240 --> 00:33:19,800
But when night falls…
451
00:33:19,880 --> 00:33:21,080
[sniffing]
452
00:33:22,600 --> 00:33:25,400
[elephant grumbles, huffs]
453
00:33:25,480 --> 00:33:26,920
…it's a different story.
454
00:33:30,240 --> 00:33:33,560
[lion breathing heavily]
455
00:33:36,240 --> 00:33:37,440
[elephants trumpeting]
456
00:33:37,520 --> 00:33:40,400
Lions are masters of chaos and confusion.
457
00:33:41,160 --> 00:33:42,240
[elephant trumpeting]
458
00:33:44,560 --> 00:33:47,200
[elephant roaring]
459
00:33:47,280 --> 00:33:49,760
[trumpeting]
460
00:33:52,280 --> 00:33:53,360
[Bosigo squeals]
461
00:33:53,440 --> 00:33:55,880
They pick the most vulnerable target…
462
00:33:59,080 --> 00:34:00,720
[Bosigo trumpeting]
463
00:34:00,800 --> 00:34:02,120
…working as a pack…
464
00:34:02,200 --> 00:34:05,040
[Bosigo continues trumpeting]
465
00:34:08,200 --> 00:34:10,280
…until there's nowhere left to run.
466
00:34:10,360 --> 00:34:12,480
[Bosigo squealing]
467
00:34:13,880 --> 00:34:14,960
[moans]
468
00:34:16,480 --> 00:34:19,520
[lions growling]
469
00:34:27,240 --> 00:34:29,600
Without the entire herd as protection,
470
00:34:30,960 --> 00:34:34,080
the lions overwhelm their prey.
471
00:34:34,160 --> 00:34:36,800
[lions continue growling]
472
00:34:36,880 --> 00:34:40,600
The drought and endless search
for food and water
473
00:34:41,440 --> 00:34:44,880
have taken their ultimate toll on Bosigo.
474
00:34:47,480 --> 00:34:49,600
[somber music playing]
475
00:34:49,680 --> 00:34:50,680
[elephant cries out]
476
00:34:52,480 --> 00:34:53,680
[grumbles]
477
00:34:55,040 --> 00:34:58,240
Elephants form deep emotional bonds.
478
00:34:58,320 --> 00:35:00,040
[elephant grumbles, huffs]
479
00:35:09,920 --> 00:35:13,080
All the family mourn Bosigo's loss.
480
00:35:14,360 --> 00:35:16,640
[elephant moaning]
481
00:35:23,600 --> 00:35:25,680
[Metsi cries out]
482
00:35:25,760 --> 00:35:28,080
[somber music continues]
483
00:35:30,480 --> 00:35:32,840
The herd gathers to comfort Metsi,
484
00:35:34,680 --> 00:35:36,960
who feels it hardest of all.
485
00:35:48,480 --> 00:35:50,720
The never-ending fight to survive
486
00:35:50,800 --> 00:35:52,480
plays out every year,
487
00:35:54,280 --> 00:35:55,720
across the Okavango…
488
00:35:58,000 --> 00:35:59,280
across our planet…
489
00:36:01,960 --> 00:36:03,040
and beyond.
490
00:36:07,080 --> 00:36:09,560
But in this battle for survival,
491
00:36:10,440 --> 00:36:12,000
Earth got truly lucky…
492
00:36:14,000 --> 00:36:17,440
with a secret guardian that protects it.
493
00:36:17,520 --> 00:36:19,200
[whooshing]
494
00:36:24,360 --> 00:36:25,480
Deep within…
495
00:36:26,200 --> 00:36:27,440
[whooshing continues]
496
00:36:28,520 --> 00:36:32,280
…the planet's raging molten furnace burns
497
00:36:32,920 --> 00:36:33,920
and churns…
498
00:36:34,440 --> 00:36:36,600
[ethereal music playing]
499
00:36:37,840 --> 00:36:40,240
…generating a powerful magnetic field
500
00:36:41,920 --> 00:36:44,360
that extends from the heart of the planet…
501
00:36:44,440 --> 00:36:46,080
[ethereal humming]
502
00:36:46,160 --> 00:36:50,680
…65,000 kilometers out towards the Sun.
503
00:36:52,600 --> 00:36:55,880
A vital force field defending Earth…
504
00:36:56,400 --> 00:36:58,240
[fire hissing]
505
00:36:58,320 --> 00:37:01,040
…from the same savage solar winds
506
00:37:02,080 --> 00:37:04,040
that stripped water from Mars.
507
00:37:07,080 --> 00:37:09,160
[ethereal music continues]
508
00:37:10,480 --> 00:37:13,920
Defeating them
before they hit our atmosphere.
509
00:37:26,520 --> 00:37:28,760
Safeguarding our essential water.
510
00:37:30,520 --> 00:37:34,160
Hugging every drop close to our planet.
511
00:37:34,240 --> 00:37:36,760
[ethereal whooshing]
512
00:37:41,040 --> 00:37:43,960
This is what makes our pale blue dot
513
00:37:44,480 --> 00:37:46,160
unlike anywhere else.
514
00:37:49,520 --> 00:37:52,920
A place where life can thrive.
515
00:37:53,000 --> 00:37:55,480
[majestic music playing]
516
00:37:56,960 --> 00:37:59,080
Bringing relief to the elephants.
517
00:38:01,600 --> 00:38:04,880
Ensuring rains return each year
without fail.
518
00:38:05,400 --> 00:38:08,320
[thunder crashing]
519
00:38:09,680 --> 00:38:14,000
In the distance,
storm clouds are building.
520
00:38:14,080 --> 00:38:15,880
[Metsi grunts, moans]
521
00:38:21,680 --> 00:38:22,600
[moans]
522
00:38:26,600 --> 00:38:29,120
[elephant huffing]
523
00:38:29,200 --> 00:38:33,800
Elephants can detect
the low-frequency rumble of thunder
524
00:38:33,880 --> 00:38:36,480
from 240 kilometers away.
525
00:38:36,560 --> 00:38:37,480
[thunder rumbling]
526
00:38:37,560 --> 00:38:38,920
[elephant grumbles]
527
00:38:39,000 --> 00:38:40,120
[trumpets]
528
00:38:43,400 --> 00:38:47,880
And it's telling them it's time
to return to the Okavango.
529
00:38:48,440 --> 00:38:51,400
[ethereal music playing]
530
00:38:56,600 --> 00:38:58,440
From the highlands of Angola,
531
00:39:00,200 --> 00:39:03,080
water is weaving its way through Botswana…
532
00:39:09,280 --> 00:39:10,800
[whooshing]
533
00:39:12,000 --> 00:39:14,280
…to rejuvenate the delta…
534
00:39:22,640 --> 00:39:24,720
with the kiss of life.
535
00:39:28,960 --> 00:39:31,600
[dramatic music playing]
536
00:39:34,480 --> 00:39:37,480
Every step
that brings the herd closer to home…
537
00:39:40,760 --> 00:39:45,280
is a continuation
of a much larger cosmic odyssey.
538
00:39:51,640 --> 00:39:57,280
From tiny molecules hitching a ride
on dust beyond Jupiter…
539
00:40:03,000 --> 00:40:05,800
to surviving the crushing heat
of early Earth.
540
00:40:05,880 --> 00:40:07,560
[rumbling]
541
00:40:09,280 --> 00:40:12,280
[whooshing]
542
00:40:13,680 --> 00:40:16,160
Imprisoned in the planet's core…
543
00:40:16,240 --> 00:40:18,120
[dramatic music swells]
544
00:40:18,200 --> 00:40:19,880
…then set free…
545
00:40:19,960 --> 00:40:21,160
[thunder crashes]
546
00:40:21,240 --> 00:40:23,080
…to sow the seeds of life…
547
00:40:23,160 --> 00:40:25,440
[elephant moaning]
548
00:40:25,520 --> 00:40:27,280
-[exploding]
-[thunder crashes]
549
00:40:27,360 --> 00:40:31,880
…every drop of water
has an amazing tale to tell.
550
00:40:34,640 --> 00:40:36,000
Every molecule…
551
00:40:36,080 --> 00:40:39,120
-[water gurgling]
-…a link in an unbroken chain…
552
00:40:39,200 --> 00:40:40,360
[elephant trumpets]
553
00:40:40,440 --> 00:40:43,400
…cycling over tens of thousands of years…
554
00:40:43,480 --> 00:40:44,960
[dramatic music continues]
555
00:40:46,480 --> 00:40:47,800
…through air…
556
00:40:50,840 --> 00:40:51,800
oceans…
557
00:40:55,680 --> 00:40:56,560
rocks…
558
00:41:01,880 --> 00:41:03,440
[dramatic music crescendos]
559
00:41:04,800 --> 00:41:05,960
…and elephants.
560
00:41:06,560 --> 00:41:08,880
[pensive music playing]
561
00:41:11,680 --> 00:41:16,040
After eight months
and hundreds of kilometers,
562
00:41:17,720 --> 00:41:21,520
Metsi and her family have finally reached
563
00:41:21,600 --> 00:41:24,960
the life-giving waters of the delta.
564
00:41:25,040 --> 00:41:27,200
[majestic music playing]
565
00:41:33,280 --> 00:41:34,480
[elephant trumpeting]
566
00:41:38,040 --> 00:41:41,640
It's well past time to drink…
567
00:41:43,880 --> 00:41:45,080
and play.
568
00:41:46,400 --> 00:41:47,360
[elephant trumpets]
569
00:41:47,440 --> 00:41:50,160
And then, drink some more.
570
00:41:50,720 --> 00:41:52,200
[elephant grumbles]
571
00:41:55,240 --> 00:41:58,000
[elephants trumpeting]
572
00:41:59,560 --> 00:42:02,040
And show the newest member of the family…
573
00:42:02,120 --> 00:42:03,800
[elephants continue trumpeting]
574
00:42:06,360 --> 00:42:09,200
…how they do things in the delta.
575
00:42:11,080 --> 00:42:12,280
[elephant trumpets]
576
00:42:15,640 --> 00:42:18,080
[elephant grumbling]
577
00:42:19,480 --> 00:42:22,280
[calm music playing]
578
00:42:22,360 --> 00:42:25,360
Metsi and her new baby cousin
579
00:42:25,440 --> 00:42:28,240
are the latest in a long line
580
00:42:28,320 --> 00:42:31,560
to benefit from water's miraculous arrival
581
00:42:32,800 --> 00:42:33,720
on this planet.
582
00:42:33,800 --> 00:42:34,680
[calf whines]
583
00:42:37,720 --> 00:42:40,240
[calm music continues]
584
00:42:44,480 --> 00:42:46,440
They will forever be connected
585
00:42:46,520 --> 00:42:47,880
to the universe
586
00:42:48,800 --> 00:42:52,280
that gave our planet this magic ingredient
587
00:42:54,040 --> 00:42:59,920
and gave us the ability
to preserve and treasure it.
588
00:43:08,440 --> 00:43:10,760
[intense music playing]
589
00:43:10,840 --> 00:43:15,120
Next, the story of our universe concludes…
590
00:43:15,200 --> 00:43:16,200
[rumbling]
591
00:43:16,280 --> 00:43:22,160
…with the force that brings everything
we've seen so far together.
592
00:43:23,560 --> 00:43:26,320
The great sculptor of the cosmos,
593
00:43:26,960 --> 00:43:27,800
gravity.
594
00:43:29,160 --> 00:43:32,520
It's a force of attraction
that built our planet.
595
00:43:32,600 --> 00:43:33,960
[intense music crescendos]
596
00:43:34,560 --> 00:43:35,480
[penguin squawks]
597
00:43:35,560 --> 00:43:39,160
And we'll bring two penguins together
at Earth's southern pole.
598
00:43:39,240 --> 00:43:40,960
[majestic music playing]
599
00:43:41,040 --> 00:43:44,120
But when did gravity
start exerting its influence?
600
00:43:45,680 --> 00:43:50,080
How does it create both order and chaos?
601
00:43:52,920 --> 00:43:57,640
And why does it make ours
the perfect planet for life…
602
00:43:57,720 --> 00:43:59,840
[chick chirping]
603
00:43:59,920 --> 00:44:00,920
…and love?
604
00:44:01,800 --> 00:44:03,080
[penguin moaning]
605
00:44:06,280 --> 00:44:08,920
[dramatic music playing]