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30 million years ago,
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tropical Africa
was covered in dense jungle.
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But not any more.
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00:00:16,840 --> 00:00:18,360
Here in East Africa,
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00:00:18,400 --> 00:00:21,200
the forest has all but vanished,
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00:00:21,240 --> 00:00:23,800
a changed landscape that is the stage
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00:00:23,840 --> 00:00:27,000
for the most epic wildlife story
on the continent.
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And it begins in the forest.
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00:00:39,880 --> 00:00:42,960
Chimpanzees are perfectly adapted
for life in the trees.
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00:00:50,280 --> 00:00:53,840
They gather almost all their food
from the canopy.
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00:01:13,080 --> 00:01:16,440
But these chimps live
in the Kyambura Gorge of Uganda,
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00:01:16,480 --> 00:01:19,360
and will sometimes embark
on an unusual journey.
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Their home,
in this narrow strip of forest,
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is surrounded by vast, open savannas...
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00:01:42,400 --> 00:01:46,200
...mile after mile of rich,
grass-covered plains.
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00:01:55,720 --> 00:02:00,360
Living on the border between forest
and savanna means the chimps
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sometimes venture into this new
and exciting habitat in search of food.
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00:02:12,640 --> 00:02:15,080
But they don't feel comfortable
in the open grasslands,
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so only forage for a few hours at a time
before returning to the forest.
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00:02:26,480 --> 00:02:29,360
However, for countless other species,
this new habitat,
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the East African plains,
has become fundamental to their survival.
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00:02:34,360 --> 00:02:39,200
So how did this part of Africa change
so dramatically?
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30 million years ago, when the jungle
still shrouded the continent,
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a vast plume of molten lava pushed up
beneath the plateau of East Africa.
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The Earth's crust cracked
under the strain,
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creating Africa's Great Rift.
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00:03:10,840 --> 00:03:13,200
Great volcanoes sprang up along the rift,
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00:03:13,240 --> 00:03:15,040
and triggered a chain of events
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that changed the face
of the landscape for ever.
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Ol Doinyo Lengai
is still an active volcano.
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Its Masai name means
"Mountain of the Gods".
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Its latest eruption covered the plains
below in a blanket of thick ash.
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Ash has a profound effect
on the surrounding vegetation.
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It dries harder than concrete.
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It's so solid that tree roots
struggle to grow through it.
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00:04:38,400 --> 00:04:40,840
Huge swathes of East Africa's Great Rift
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are covered in tree-resistant
volcanic ash...
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...stretching on the east side
from Tanzania into northern Kenya,
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and along the arm of the shorter Western
Rift up the valley floor of Uganda.
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00:05:18,080 --> 00:05:22,400
The rising rift valley
not only created towering volcanoes,
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it forced up great chains of mountains
like these,
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the mighty Ruwenzori.
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They stand three miles high,
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and like all the great highlands
of the Rift,
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they have a huge effect
on the local weather
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and, in turn, the surrounding vegetation.
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Mist and cloud rolls in from
the drenched jungles of the Congo Basin
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that lie directly west of the Ruwenzori.
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Warm, moist air rises up the mountains.
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As it does, it cools, so most
of the moisture falls on the slopes,
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00:06:15,880 --> 00:06:18,600
and little rain reaches
the plains to the east.
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It's the Rift's unique combination
of restricted rain and volcanic ash
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that keeps the forests at bay.
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But the space left behind
is now a battleground.
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Two determined colonisers fight
to stake their claim on the plains.
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00:06:41,960 --> 00:06:46,080
One competitor is rather small
and unassuming -
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grass...
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...its challenger the only tree that still
holds out for its place in the savannas...
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...the thorn tree of Africa - the acacia.
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00:07:05,920 --> 00:07:08,800
It's able to cope
because its shallow roots
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can extract any moisture from
the soil above the hard ash pan...
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...and its tiny leaves reduce
water lost by evaporation.
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It's so successful,
it can grow six metres tall.
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But it has a predator to match.
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00:07:37,840 --> 00:07:40,120
The acacia's small leaves
are nutritious enough
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to support the world's tallest antelope...
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...lofty enough to exploit a niche
that no others can reach.
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00:07:58,080 --> 00:08:01,360
But the acacia crown is not only attacked
from the top down,
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but also from the bottom up.
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00:08:08,600 --> 00:08:11,280
The gerenuk has a skeleton
that's adapted
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to enable it to spend all day
standing on its hind legs.
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But height isn't the only key
to unlock the acacia's defences.
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The dik-dik is one of
Africa's shortest antelopes.
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It can't reach the high crown,
and at ground level,
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the acacia thorns are at their fiercest.
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But the dik-dik's tiny head
fits perfectly between the spikes,
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and so the acacia
is attacked from every angle.
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The acacia can just about cope
with the impact of nibblers like these,
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00:08:56,760 --> 00:09:00,640
but there's one heavyweight
that does more than just snack.
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00:09:12,720 --> 00:09:15,280
Seedling acacias are simply annihilated
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by the world's heaviest vegetarian.
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But adult trees aren't safe, either.
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The elephant's trunk is sensitive enough
to select individual leaves...
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...but strong enough
to rip off entire branches.
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The combination of tusk and trunk
makes short work of heavy wood...
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00:09:49,960 --> 00:09:53,280
...and a three-tonne body
makes an effective bulldozer.
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A single African elephant
can flatten a tree a day.
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And in the savannas of the Rift,
the herds number over 150,000...
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...capable of wiping out
entire acacia woodlands.
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Landscape gardening on this scale
plays an important role
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in helping the acacia's competitor, grass.
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Grass makes up over 50% of an elephant's
diet, so it's in their own interests
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to clear the trees
and maintain space for grass to grow.
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00:10:56,640 --> 00:11:01,080
Grass, unlike other plants,
grows from its roots instead of the tip.
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00:11:02,840 --> 00:11:05,760
This gives it astonishing powers
of regeneration.
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00:11:05,800 --> 00:11:09,760
It also means it can be
almost constantly cropped -
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a never-ending supply of food.
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This indestructible plant
has taken over the Rift Valley plains.
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It supports the greatest numbers
and diversity
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00:11:27,560 --> 00:11:30,040
of large grazers in the world.
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But there is a downside.
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Grass is hard to process, so grazers
have to consume vast amounts.
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That means big guts,
and big guts need a big body.
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A diet of grass also means eating
for up to 16 hours per day,
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and that leaves little time
for the other important tasks.
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These are Uganda kob,
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the most abundant antelope
in the Western Rift Valley.
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Somehow they find time to indulge
in a surprisingly complex mating ritual.
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The kob have a dedicated mating ground,
known as a lek.
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It's where males gather
to flaunt themselves,
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and the females turn up to pick a mate.
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The males want to hold the best spot.
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To win it, they have to fight.
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It's all to impress the ladies,
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who are very picky when it comes
to choosing the right mate.
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The females are after the buck
with the best blood -
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the strongest male,
holding the most coveted position
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right in the middle of the lek.
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The female chooses her mate,
and then allows him
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00:14:31,040 --> 00:14:34,880
to test her scent for hormones
to confirm she's ready to mate.
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00:14:37,640 --> 00:14:41,320
A female comes into season
every 20 days or so,
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but is only receptive
for a couple of hours,
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so there's not much time for flirting.
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Job done.
The exchange of genes is complete.
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Now the female can relax
under the protection of her champion.
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There is a selfish reason
behind her choice.
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The middle of the lek
is actually the safest spot,
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as a concentration of distracted antelope
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attracts the inevitable antelope eaters.
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Adult lions hunt best working as a pride,
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but this single mother is alone,
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so providing for her family
of three teenage cubs is all down to her.
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00:15:51,120 --> 00:15:54,480
Kob are fast, with excellent eyesight,
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and so during the day,
catching one is extremely tricky.
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But as night falls,
the advantage swings to the hunter.
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For the mother lioness,
hunting is a serious business...
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...best done without
her three boisterous cubs.
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The mother wears a radio collar
so scientists can track her movements,
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but it doesn't hinder her hunting.
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In the pitch black of the moonless night,
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both the kob and lioness
are reduced to near blindness.
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They can smell each other,
but the lioness can't pinpoint a target
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unless it makes a sound.
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00:17:13,920 --> 00:17:19,600
So as long as the kob hold their nerve
and don't break cover, they'll be safe.
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Meanwhile, the hungry and impatient cubs
wander into trouble.
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The three cubs might look dangerous,
but they are only ten months old
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and they won't learn to hunt properly
until they're two.
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00:18:30,600 --> 00:18:33,520
They're no match for these buffalo,
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but the opportunity for stalking practice
is too good to miss.
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Meanwhile,
their mother is on to something.
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She digs down almost a metre.
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After a huge effort,
she only pulls out a tiny meal -
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barely a mouthful.
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But satisfying hunger
is not on this mother's agenda tonight.
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These warthog piglets are a perfect size
for the cubs to practise killing.
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She pulls out six
and saves them all for her young.
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The sooner the cubs learn to hunt,
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the sooner they'll be able
to help their mother.
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00:20:58,160 --> 00:21:01,360
Ambushing prey at night
is very effective,
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00:21:01,400 --> 00:21:04,440
but it's not the only way
for a cat to catch a meal.
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The cheetah is the fastest runner
on the planet,
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but here, speed is no good
without stealth.
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He must use camouflage
to creep up on his target.
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With only the grass as cover,
he can't get close enough for a sprint.
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and as the hartebeest
is one of Africa's fastest antelopes,
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from this distance
he has no chance in a straight race.
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But it might still be worth a go.
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Unfortunately for him,
they are all fit and well.
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A full sprint is heavy work
for a cheetah under the hot sun.
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He'll need time to recover
before he can try again.
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Antelope like this topi
use the long grass
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to hide their babies from predators.
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If they stay still they won't be found.
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But what if you want to be seen?
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Then long grass can be rather a nuisance.
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This male widow bird has prepared
a dance floor to seduce a female.
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00:24:30,960 --> 00:24:33,520
But first, he needs to get her attention.
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The modestly clad females
are currently on the fence.
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When one flies in for a closer look...
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...a male gives it all he's got.
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00:25:35,200 --> 00:25:38,720
The Rift's grasslands bake
beneath the African sun.
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The long grass can become very dry,
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and that makes it vulnerable to
one of nature's most powerful forces...
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...fire.
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00:26:18,120 --> 00:26:24,200
Thousands of tonnes of dry grass
is enough to fuel a blazing inferno.
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But the flames can provide a feast.
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Migrating sand martins brave the smoke
to take advantage
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of the tiny insects
that flee the flames...
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...a welcome windfall
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to a bird on a 1,000-mile journey
from Africa to Europe.
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This looks like devastation.
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00:27:37,400 --> 00:27:43,040
The grass has been burnt away,
and so have the seedling trees.
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00:27:43,080 --> 00:27:47,280
But because grasses store energy
underground in their roots,
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within days, new sprouts
push through the fertile ash.
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00:27:55,280 --> 00:27:59,720
Grass may be tough enough
to survive even the hottest fire...
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...but there is one force of nature here
that grass cannot defend against.
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It's an extraordinary creature,
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and it only comes out at night.
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00:28:18,080 --> 00:28:21,440
A hippopotamus has a mouth
half a metre wide,
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built for devouring grass -
40 kilograms in one sitting.
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00:28:27,200 --> 00:28:29,800
A fussy eater, it only likes short grass,
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which it tears up with great lips.
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Hippopotamus roam for miles
between dusk and dawn
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in search of good grazing.
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00:28:53,520 --> 00:28:56,520
But there's a limit to their range,
and they must turn around
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00:28:56,560 --> 00:29:00,200
and head back to water
before the sun rises.
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00:29:41,200 --> 00:29:44,280
The still, shallow waters
bear their great weight.
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00:29:47,080 --> 00:29:51,480
Now they relax, snooze,
and socialise in comfort.
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00:30:13,960 --> 00:30:16,640
Mzima Springs lie in the Eastern Rift,
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a source of water filtered through ancient
Rift Valley lava that never dries up.
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This is a haven
for a small population of hippo,
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who graze the savanna
in a ten-mile radius around the spring.
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00:30:36,080 --> 00:30:39,880
But now the surrounding area
is in the deathly grip of drought.
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00:30:41,240 --> 00:30:44,240
With no rain,
the grass has stopped growing.
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00:30:46,960 --> 00:30:51,440
Like all hippos, the Mzima herd
are bound to their pool,
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00:30:51,480 --> 00:30:54,280
so can't escape
to search for pastures new.
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00:31:12,800 --> 00:31:16,720
Before long, the hippos will eat
everything within range,
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00:31:16,760 --> 00:31:19,440
and that will create a disaster.
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They brave the sun in a desperate search
for food, but to no avail.
220
00:31:30,640 --> 00:31:34,200
Weakened, they sicken and die...
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00:31:47,360 --> 00:31:51,040
...but not before they have reduced
this savanna to a dust bowl.
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00:31:56,200 --> 00:31:59,040
The topsoil has blown away,
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00:31:59,080 --> 00:32:01,560
and even the roots of the grasses
are destroyed.
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00:32:03,400 --> 00:32:08,400
It will take this part of the Great
Rift Valley many years to recover.
225
00:32:24,600 --> 00:32:29,280
The rain shadow of the Rift Valley
makes the grasslands extremely dry...
226
00:32:31,760 --> 00:32:36,600
...but just enough rain makes it across
the mountains to keep the grass alive.
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00:33:35,520 --> 00:33:38,960
Not everyone enjoys the rain.
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00:34:28,280 --> 00:34:33,600
But for the Uganda kob, it's a joy
not to feel plagued by hunger or thirst.
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00:35:10,120 --> 00:35:14,160
When the rain clouds make it
across the mountains of the Western Rift,
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00:35:14,200 --> 00:35:16,600
they bring the grasslands
exploding to life.
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00:35:37,000 --> 00:35:41,360
The prevailing winds that bring the rain
move in a north-south cycle
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00:35:41,400 --> 00:35:43,120
up and down the continent.
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00:35:44,760 --> 00:35:48,400
The resulting wet seasons
bring intense downpours,
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00:35:48,440 --> 00:35:50,680
but not to everywhere at once.
235
00:36:00,280 --> 00:36:03,360
These isolated rains
mean that some animals
236
00:36:03,400 --> 00:36:07,680
have to run for thousands of miles
in search of freshly grown grass.
237
00:36:37,840 --> 00:36:40,480
Every year, almost two million wildebeest
238
00:36:40,520 --> 00:36:43,080
follow the thunder clouds
like storm chasers,
239
00:36:43,120 --> 00:36:46,480
trekking from the Serengeti
to the Masai Mara.
240
00:36:52,560 --> 00:36:57,040
And in their wake
comes Thomson's gazelle.
241
00:36:57,080 --> 00:37:00,520
Tommies are one of the smaller antelope
found in the Rift savannas.
242
00:37:00,560 --> 00:37:04,640
Their size makes them
very vulnerable to predators.
243
00:37:20,840 --> 00:37:24,600
These cheetahs have been waiting
for the tommies for months.
244
00:37:24,640 --> 00:37:28,040
Now's their chance
to eat as much as they can.
245
00:37:38,360 --> 00:37:41,520
Each cat has a different style of hunt,
246
00:37:41,560 --> 00:37:43,280
but stealth is always key
247
00:37:43,320 --> 00:37:46,840
if they are to stand a chance
against the fleet-footed tommy.
248
00:38:26,960 --> 00:38:29,120
The cheetah is faster,
249
00:38:29,160 --> 00:38:32,560
but the tommy can turn quicker
and has more stamina.
250
00:38:46,240 --> 00:38:50,000
Each chase lasts
only 300 metres at most,
251
00:38:50,040 --> 00:38:53,320
but those few seconds
decide the fate of the tommy.
252
00:39:09,160 --> 00:39:13,840
In a fair chase, the cheetah has
a 50/50 chance of catching a meal -
253
00:39:13,880 --> 00:39:17,280
the highest success rate
of all the African big cats.
254
00:40:06,240 --> 00:40:09,960
An unlucky stumble is enough
to seal a tommy's fate.
255
00:40:38,080 --> 00:40:42,480
For savanna herbivores,
living here has a price.
256
00:40:43,480 --> 00:40:46,920
But the richness of these grasslands
make it worth the risk,
257
00:40:46,960 --> 00:40:51,360
and the rewards are so tempting that
even a primate has made them home.
258
00:40:53,960 --> 00:40:56,400
Primates are normally forest dwellers.
259
00:40:56,440 --> 00:41:00,080
To flourish on the open plains
has been a hard step to take.
260
00:41:04,800 --> 00:41:07,040
The olive baboon
is one of very few monkeys
261
00:41:07,080 --> 00:41:09,800
to make a success of savanna life.
262
00:41:14,080 --> 00:41:17,920
For a small animal on the plains,
there's safety in numbers.
263
00:41:31,200 --> 00:41:34,880
Living in a large troop
requires organisation.
264
00:41:36,240 --> 00:41:38,200
To avoid constant squabbling,
265
00:41:38,240 --> 00:41:41,840
the baboons have developed
a sophisticated social order.
266
00:41:45,080 --> 00:41:48,880
Regular grooming
is not just for reasons of hygiene.
267
00:41:48,920 --> 00:41:52,840
The constant contact
is important for social bonding.
268
00:41:52,880 --> 00:41:55,400
It's a good way to make friends.
269
00:42:01,160 --> 00:42:04,040
Males are tough enough
to look after themselves,
270
00:42:04,080 --> 00:42:05,960
and come and go as they choose.
271
00:42:07,680 --> 00:42:10,640
But mothers and babies
must stick together.
272
00:42:16,760 --> 00:42:20,880
The little ones are very important
for establishing rank and order.
273
00:42:32,880 --> 00:42:37,520
This baby is being used
to keep its mother in her place.
274
00:42:37,560 --> 00:42:41,200
The mother must sit
and watch it being treated roughly
275
00:42:41,240 --> 00:42:43,120
by the more dominant female
276
00:42:43,160 --> 00:42:45,960
if she wants to stay
within the safety of the troop.
277
00:42:46,000 --> 00:42:50,920
Her low rank means she has no choice
but to tolerate her oppressor.
278
00:43:11,760 --> 00:43:15,720
Whilst the inequalities of baboon society
might seem harsh,
279
00:43:15,760 --> 00:43:19,320
this system of complex relationships
and communication
280
00:43:19,360 --> 00:43:22,280
is essential
for their survival in the savanna.
281
00:43:47,720 --> 00:43:49,400
When darkness falls,
282
00:43:49,440 --> 00:43:51,520
the baboons' sharp senses fail them
283
00:43:51,560 --> 00:43:54,440
and they must return to the trees
to sleep,
284
00:43:54,480 --> 00:43:56,600
safe from night prowlers.
285
00:44:16,520 --> 00:44:18,800
Baboon behaviour can give an insight
286
00:44:18,840 --> 00:44:22,120
into what it takes for any primate
to survive on the savanna.
287
00:44:25,760 --> 00:44:30,680
Our own primate ancestors may have coped
on the open plains in a similar way.
288
00:44:33,800 --> 00:44:36,120
But there's another primate
in the Rift Valley
289
00:44:36,160 --> 00:44:39,320
that can tell us more
about our ancient history.
290
00:44:55,640 --> 00:45:00,120
In Uganda's Kibale Forest,
chimps are bedding down for the night.
291
00:45:04,800 --> 00:45:09,120
They bend branches into a nest
for a restful night's sleep,
292
00:45:09,160 --> 00:45:11,880
just as our common ancestors
might have done
293
00:45:11,920 --> 00:45:13,760
over eight million years ago.
294
00:45:28,640 --> 00:45:33,080
Our ancient relatives living
in the primeval jungles of Africa
295
00:45:33,120 --> 00:45:38,040
shared the well-developed brains
and nimble hands of modern chimpanzees.
296
00:45:53,120 --> 00:45:56,240
But at the same time
that the Great Rift Valley formed
297
00:45:56,280 --> 00:45:59,840
and the forests were pushed back,
our ancestors moved out
298
00:45:59,880 --> 00:46:04,640
into the savannas, leaving
their chimpanzee relatives behind.
299
00:46:12,720 --> 00:46:16,840
Chimpanzees are still poorly adapted
for savanna life.
300
00:46:20,400 --> 00:46:24,040
Their bodies are too squat
to see over the long grass,
301
00:46:24,080 --> 00:46:26,520
and their limbs aren't built for speed
302
00:46:26,560 --> 00:46:29,440
like an antelope
that can outrun predators.
303
00:46:44,960 --> 00:46:50,080
But like humans today,
our ancestors walked tall on two legs
304
00:46:50,120 --> 00:46:54,840
and had hands free to carry weapons
for hunting and defence.
305
00:46:58,880 --> 00:47:01,880
More meat in our diet
meant our brains expanded
306
00:47:01,920 --> 00:47:06,360
and our societies grew
ever more complex and powerful.
307
00:47:08,400 --> 00:47:12,200
In time,
we became masters of the savanna.
308
00:47:14,440 --> 00:47:18,240
We owe our extraordinary success
as a species to this place -
309
00:47:18,280 --> 00:47:20,640
the cradle of humanity...
310
00:47:22,320 --> 00:47:25,080
...in Africa's Great Rift Valley.
311
00:47:43,880 --> 00:47:47,600
Filming sleeping chimps in the forests
of Kibale National Park
312
00:47:47,640 --> 00:47:51,080
presented some serious challenges
for the crew.
313
00:47:52,320 --> 00:47:56,800
They had to climb huge tropical trees
in the pitch dark.
314
00:47:58,400 --> 00:48:00,880
But first they had to find the chimps,
315
00:48:00,920 --> 00:48:04,520
and that meant trekking
for miles through the jungle
316
00:48:04,560 --> 00:48:06,560
with some serious baggage.
317
00:48:15,160 --> 00:48:18,160
Once they found them,
they had to wait until dark,
318
00:48:18,200 --> 00:48:20,680
when the chimps
had picked their nesting spots.
319
00:48:25,440 --> 00:48:29,120
Their mission was to climb into the canopy
and film the chimps sleeping -
320
00:48:29,160 --> 00:48:30,960
from above.
321
00:48:31,000 --> 00:48:35,920
But this meant climbing in the dark,
which would put the crew to the test.
322
00:48:37,920 --> 00:48:42,320
Chimps nest anywhere
between 4 and 40 metres off the ground,
323
00:48:42,360 --> 00:48:45,360
and never in the same place twice.
324
00:48:45,400 --> 00:48:48,720
The first task is to find a tree
suitable for climbing
325
00:48:48,760 --> 00:48:50,640
without disturbing the chimps.
326
00:48:52,200 --> 00:48:53,880
When darkness falls,
327
00:48:53,920 --> 00:48:58,400
the team use image-intensifying scopes
to look into the canopy.
328
00:48:58,440 --> 00:49:03,080
The final say goes
to tree-climbing expert Tim Fogg.
329
00:49:03,120 --> 00:49:04,920
It's not good at all.
330
00:49:04,960 --> 00:49:09,720
There are no trees which give us
a view of the nests tonight.
331
00:49:09,760 --> 00:49:14,560
It's just really frustrating,
because they're... they're all here -
332
00:49:14,600 --> 00:49:19,120
there's about six or seven nests
right above us and a bit off to that side,
333
00:49:19,160 --> 00:49:21,920
but there's no big trees
overlooking them,
334
00:49:21,960 --> 00:49:25,920
so we're stuck...
stuck on climbing tonight.
335
00:49:25,960 --> 00:49:28,440
I think we'll probably just do
ground shots of them.
336
00:49:28,480 --> 00:49:31,680
I can't see anything I can get up
that's any use at all.
337
00:49:31,720 --> 00:49:36,000
Grounded for the night,
they set up the kit on the forest floor.
338
00:49:37,720 --> 00:49:43,000
Cameraman Martin Dohrn has developed
a brand-new night-vision camera
339
00:49:43,040 --> 00:49:46,400
that can see
without any artificial light at all.
340
00:49:46,440 --> 00:49:49,640
It's called a starlight camera
341
00:49:49,680 --> 00:49:52,200
and it uses an image intensifier
that means it can capture
342
00:49:52,240 --> 00:49:56,200
unique animal behaviour
not usually visible to the human eye.
343
00:49:59,120 --> 00:50:04,400
Amazingly, we have now got
a shot of a sleeping chimpanzee.
344
00:50:04,440 --> 00:50:06,560
It's not a great shot,
345
00:50:06,600 --> 00:50:08,960
it's not a remarkable shot,
346
00:50:09,000 --> 00:50:11,680
but it is probably the first time ever
347
00:50:11,720 --> 00:50:16,720
that a chimpanzee has been filmed
asleep in its tree nest.
348
00:50:19,080 --> 00:50:23,760
This is actually kind of like Big Brother,
only more interesting.
349
00:50:25,680 --> 00:50:29,880
But the team aren't satisfied
with filming from the ground.
350
00:50:31,160 --> 00:50:33,600
Encouraged by their terrestrial success,
351
00:50:33,640 --> 00:50:36,640
the next night sees the crew
stalk the chimps
352
00:50:36,680 --> 00:50:38,480
to a much better location for climbing.
353
00:50:42,080 --> 00:50:44,560
There is a big tree
right in the back there.
354
00:50:44,600 --> 00:50:47,120
It's just whether we'd get a view through.
355
00:50:47,160 --> 00:50:50,160
The big tree behind that.
There's a much higher tree behind that.
356
00:50:50,200 --> 00:50:51,320
Yeah, I think so.
357
00:50:51,360 --> 00:50:55,120
Tim aims his catapult
at a branch high in the canopy.
358
00:50:58,880 --> 00:51:01,040
OK. I think I got that.
359
00:51:02,520 --> 00:51:04,320
Chimps are super-sensitive in the night,
360
00:51:04,360 --> 00:51:08,520
and no-one knows how they'll react
to a film crew swinging above them.
361
00:51:16,680 --> 00:51:20,160
Getting the ropes up
is just the start of the climbing process.
362
00:51:21,960 --> 00:51:27,920
We've got to load-test the ropes now, and
what I'm dreading is that when we pull...
363
00:51:27,960 --> 00:51:31,800
We're going to hang two of us on the ropes
to see if the branches will hold it,
364
00:51:31,840 --> 00:51:33,880
and if it breaks,
365
00:51:33,920 --> 00:51:37,960
I don't know, well, it's going to cause
mayhem with the chimps.
366
00:51:38,000 --> 00:51:40,040
It's... But we have to try.
367
00:51:40,080 --> 00:51:41,880
Safety-wise, I can't go up there
368
00:51:41,920 --> 00:51:45,120
without seeing that the branches are
strong enough to take me, so that's it.
369
00:51:52,600 --> 00:51:54,840
Satisfied the ropes are strong enough,
370
00:51:54,880 --> 00:52:00,040
Tim heads up the tree with no idea
what he might find in the jungle canopy.
371
00:52:06,120 --> 00:52:10,960
OK, well, it didn't go to plan, really,
because, er... I started climbing...
372
00:52:11,000 --> 00:52:15,040
The ropes went in really easily,
amazingly, and then I started to climb,
373
00:52:15,080 --> 00:52:21,160
and as soon as I hit some foliage,
I started getting the odd little itch.
374
00:52:21,200 --> 00:52:25,560
And by the time I got through
the first bit of foliage, I was flailing.
375
00:52:25,600 --> 00:52:29,960
I was covered in tiny little ants
that were just on a suicide mission.
376
00:52:30,000 --> 00:52:32,520
They were just eating me alive.
377
00:52:32,560 --> 00:52:35,040
And I tried to climb on,
378
00:52:35,080 --> 00:52:38,240
and I got a bit further up,
and they were still going at me.
379
00:52:38,280 --> 00:52:41,240
They started getting in my sleeves
380
00:52:41,280 --> 00:52:43,240
and then all around my waist,
381
00:52:43,280 --> 00:52:46,120
and then they started getting
all round my neck.
382
00:52:46,160 --> 00:52:48,760
They got in my helmet as well,
so at one point
383
00:52:48,800 --> 00:52:50,920
I had to get my helmet off
and try and shake them out.
384
00:52:50,960 --> 00:52:52,800
Nasty little things.
385
00:52:55,520 --> 00:53:00,960
Undeterred by creepy-crawlies,
Tim and the team head back to the jungle
386
00:53:01,000 --> 00:53:03,000
hoping for a more successful climb.
387
00:53:07,800 --> 00:53:09,880
It's incredibly close.
388
00:53:09,920 --> 00:53:16,160
It's about... maybe six metres
above and just behind me.
389
00:53:16,200 --> 00:53:18,400
The tree I'm going for
is just over that way.
390
00:53:18,440 --> 00:53:23,200
That should give us a good shot
down on him... in his nest.
391
00:53:23,240 --> 00:53:26,200
That's what we're aiming for.
392
00:53:26,240 --> 00:53:29,360
I've noticed that I'm right on
a big pile of elephant-do.
393
00:53:33,360 --> 00:53:36,640
Just putting on some insect repellent.
394
00:53:36,680 --> 00:53:38,880
Then I'm going to tape my sleeves up
395
00:53:38,920 --> 00:53:44,440
because I want to try and keep
the ants out if they're there this time.
396
00:53:49,280 --> 00:53:54,560
Geared up once again,
Tim heads up to check the view.
397
00:53:59,080 --> 00:54:01,640
Martin prepares to record from the ground,
398
00:54:01,680 --> 00:54:05,040
and tree-climbing specialist
cameraman Nick Turner
399
00:54:05,080 --> 00:54:07,360
can finally take to the trees.
400
00:54:11,160 --> 00:54:14,240
And right behind him,
Martin sends up a precious cargo.
401
00:54:19,080 --> 00:54:23,320
The world's only HD starlight camera
is in the bag,
402
00:54:23,360 --> 00:54:27,680
so let's not stand under it
in case it falls.
403
00:54:34,600 --> 00:54:38,640
It's a real mess up here with gear,
I mean, we know where everything is,
404
00:54:38,680 --> 00:54:44,160
but it's just everything has to be
tied on so we don't drop anything.
405
00:54:44,200 --> 00:54:47,920
There's cables and tapes and ropes
and karabiners all over the place.
406
00:54:47,960 --> 00:54:51,240
We're about 15 metres off the deck
407
00:54:51,280 --> 00:54:57,200
and the chimps are about 10 to 12 metres
away from us, down slightly.
408
00:54:57,240 --> 00:55:00,760
The team are close to success.
409
00:55:00,800 --> 00:55:02,960
But before they can even take a shot...
410
00:55:04,520 --> 00:55:06,600
What's going on?
411
00:55:06,640 --> 00:55:08,880
...the armed ranger has heard something.
412
00:55:12,760 --> 00:55:16,680
It seems we've got some elephants
coming close to us
413
00:55:16,720 --> 00:55:19,920
and we're not sure what to do
or what they're going to do.
414
00:55:19,960 --> 00:55:23,320
So we're leaving our lights on
so the elephants can see us
415
00:55:23,360 --> 00:55:25,280
and don't get suddenly surprised.
416
00:55:25,320 --> 00:55:29,320
I'm pretty sure
they'll just try and stay away from us...
417
00:55:29,360 --> 00:55:31,760
but you never know.
418
00:55:31,800 --> 00:55:34,720
Elephants have very poor eyesight
in the dark.
419
00:55:34,760 --> 00:55:39,400
If they come across the crew,
they might take fright and attack.
420
00:55:39,440 --> 00:55:42,240
We think that might be an elephant.
421
00:55:42,280 --> 00:55:45,200
We should have a B-plan here.
422
00:55:45,240 --> 00:55:50,160
They're probably curious
rather than dangerous, but...
423
00:55:50,200 --> 00:55:53,680
I'm not an expert in elephant behaviour.
424
00:55:53,720 --> 00:55:57,760
My plan is to run behind the tree
and hide.
425
00:55:57,800 --> 00:55:59,320
Possibly even...
426
00:55:59,360 --> 00:56:01,200
try and climb up into it.
427
00:56:01,240 --> 00:56:02,760
Probably get up there.
428
00:56:04,440 --> 00:56:08,360
I'm afraid that's the best I can offer.
429
00:56:08,400 --> 00:56:10,120
You're probably quite safe up there.
430
00:56:10,160 --> 00:56:12,520
I don't think they'd be able
to knock the tree down
431
00:56:12,560 --> 00:56:15,640
but what I'll make sure I do
is I'll set the thing in
432
00:56:15,680 --> 00:56:19,040
to record before I go, so...
433
00:56:19,080 --> 00:56:22,480
I can't imagine the chimps will be
too happy about having elephants
434
00:56:22,520 --> 00:56:24,160
running around like that.
435
00:56:25,400 --> 00:56:29,520
With nowhere to hide, the crew carries on
436
00:56:29,560 --> 00:56:31,480
and the guard comes back with news.
437
00:56:33,240 --> 00:56:35,120
There's a chimpanzee.
438
00:56:35,160 --> 00:56:39,680
- It's a chimpanzee. Are you sure?
- Yes, of course.
439
00:56:41,480 --> 00:56:44,800
The chimps have been
playing tricks on the crew.
440
00:56:44,840 --> 00:56:47,400
So once the fear of elephants is passed,
441
00:56:47,440 --> 00:56:51,680
they can get on and film the nesting
chimps from high in the canopy.
442
00:57:04,520 --> 00:57:08,120
Martin's starlight camera gives us
a grainy black-and-white image,
443
00:57:08,160 --> 00:57:11,040
but allows us to see into the night
444
00:57:11,080 --> 00:57:14,560
and watch wildlife
at their most intimate moments.
445
00:57:31,360 --> 00:57:33,640
It showed for the very first time
446
00:57:33,680 --> 00:57:36,680
how these great apes snuggle down
in the treetops
447
00:57:36,720 --> 00:57:42,600
and how it's possible to have
a comfortable night's sleep in the jungle.
39756
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