Water The Great Rift: Africa's Wild Heart


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RAIN PATTERS GENTLY

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GRUNTS

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It's raining...again.

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2.5 miles up in Africa's Virunga mountains,

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the weather is mostly miserable.

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There's no point looking for shelter.

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The resident gorillas' fur

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is thick enough to keep them warm, even when it's wet.

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For sun lovers,

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the Virungas wouldn't rate high as a holiday destination.

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But without this rain,

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the gorillas wouldn't have food in such abundance.

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And there would be no grass on the plains below.

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THUNDER RUMBLES

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WILDEBEEST LOW

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Across Africa's vast Rift Valley,

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it's where the rain falls and how it interacts with the landscape

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that determines who will prosper and who will die.

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Spanning 3,000 miles along the length of East Africa,

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the Great Rift is a complex of enormous valleys, volcanoes and grassy plains.

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The Great Rift was created

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when a plume of super-hot lava pushed up beneath Africa

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over millions of years.

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But once the whole area had been lifted more than a mile high,

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cracks appeared around the margins...

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..creating the Eastern Rift on one side...

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..and the Western Rift on the other.

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In the giant clefts of the Rift Valley,

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water collects in vast lakes,

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home to dazzling arrays of colourful fish.

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THUNDER RUMBLES

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The Rift's rain-drenched mountains in turn feed Africa's mightiest rivers,

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whose tributaries provide a lifeline for thirsty game in times of drought.

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But not all the fresh water here is good for life.

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Ash from volcanic eruptions turns the shallow lakes of the Eastern Rift

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into caustic death traps.

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At its northern end, the Great Rift plunges into the Red Sea,

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creating a dazzling world of coral

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and ocean trenches hiding deep secrets.

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Few places on Earth provide such a range of aquatic habitats.

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So how has wildlife adapted

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to the challenges and opportunities of the Great Rift's watery worlds?

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HIPPOS BELLOW

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All the water in the Rift begins as rain.

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Converging trade winds create cloud masses

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which move up and down the length of Africa,

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producing two rainy seasons each year,

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bringing the landscape to life.

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At the end of the long wet season, the Rift's rivers are brimful of water.

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There's abundant food for the hippos and other riverside residents.

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But the good times won't last for long.

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As the rains retreat northwards and the grasslands dry and wither,

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drinking water becomes increasingly scarce

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for the Great Rift's wild inhabitants.

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In the savannas, lakes and pools evaporate

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until only the rivers remain.

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The increasingly arid landscape poses a problem for these African buffalo.

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Because dry grass is difficult to digest,

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each buffalo needs to drink 34 litres a day.

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As the grazing close to the river is used up,

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they face a longer and longer daily trek

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between their feeding grounds and watering places.

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Buffaloes can smell water from a long way off

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and follow established trails through the bush

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which lead to favourite drinking spots.

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As the buffaloes drink, fluttering oxpeckers get a chance

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to remove ticks and other parasites from their faces.

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It's the only time they will tolerate

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sharp beaks picking around sensitive eyes and ears.

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TRUMPETING AND GRUNTING

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Elephants are even more dependent on the river.

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In this hot climate, an adult elephant

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needs to drink a staggering 200 litres a day just to survive.

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This family share their favourite drinking spot with other elephants.

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So as well as slaking their thirst,

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the river provides a focus for their social life.

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River mud provides excellent protection against the African sun.

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With a belly full of water and a coat of sunscreen,

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the elephants head off towards the blistering savanna.

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While the falling water level is bad for elephants and buffaloes,

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it's just what these bee-eaters need.

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They dig their nesting burrows in the vertical banks of Rift Valley rivers,

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which are only exposed in the dry season once water levels have fallen.

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BEE-EATERS TWITTER

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Three months ago, this entire nesting site was underwater

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and the birds were far away in the jungles of the Congo.

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Nesting on an exposed mud cliff makes the bee-eaters nervous.

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And with good reason.

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An African fish eagle has taken up residence on the bank-top.

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But it's not here to admire the view.

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Fish eagles' huge feet

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are designed to grab slippery fish from the water surface,

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but they are good for other prey too.

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The shrinking rivers create a serious problem for another Rift resident.

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Hippos' dependence on water is absolute - they only feel safe

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where it's deep enough for them to submerge completely.

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Hippos feed at night

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and spend the day digesting their dinner in the safety of the river.

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While the grown-ups snooze...

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..the youngsters play.

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Young hippos are very curious.

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HISSES

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As the river shrinks,

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the hippos crowd together in the few remaining deep-water pools.

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Each stretch of river is controlled by a dominant bull,

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who tolerates other hippos in his patch

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so long as they behave themselves and defer to him.

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Keeping your head down and bottom up while spraying dung in all directions

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counts as good manners in hippo society.

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But jostling your neighbour is considered very bad behaviour.

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Any ruckus in such crowded conditions spreads like a shock wave,

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causing a multiple pile-up of grumpy hippos.

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It's bad news for the hippo at the end

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who gets pushed into the path of the resident bully.

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Once the pecking order has been restored, everyone can settle down.

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But there's a darker side to life in the Rift's river world.

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At the peak of the dry season,

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an anthrax epidemic sweeps through the crowded colony,

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killing dozens of hippos.

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The smell of death carries in the current.

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Within a few hours, the hippo carcass

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has attracted more than a hundred crocodiles from far downstream.

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Crocs' ultra-efficient immune system

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allows these reptiles to eat diseased meat without getting sick.

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The smaller crocs hang back while their elders guzzle and gulp...

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..shadowed by a hopeful heron on the lookout for fish.

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But it's the crocs' day.

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Life and death are never far apart in the waters of the Great Rift.

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But not every lake or river

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is at the mercy of the seasons and the sun.

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Beneath the Great Rift's rolling hills,

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porous volcanic rocks channel water deep underground,

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sometimes for many miles.

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The subterranean water eventually pops out as a spring,

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like this one at Mzima in southern Kenya,

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feeding an oasis of crystal-clear streams and lakes.

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Because it's supplied from a large underground reservoir,

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a volcanic spring like Mzima continues to flow

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even at the height of the dry season...

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..providing a year-round haven for wildlife.

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SNORTS

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And the Rift's unique geology

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has produced another kind of water supply

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that's equally immune from drought.

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Plunging six miles deep,

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Lake Tanganyika is Africa's greatest natural reservoir.

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It contains 30 trillion litres of water...

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..and stretches 400 miles along the Western Rift Valley.

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Its sister lake, Malawi, has a similar profile.

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Lake Malawi is famous for its extraordinary diversity of cichlids.

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More than a thousand unique varieties found nowhere else on Earth.

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All are believed to be descended from just a handful of species

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which have evolved a dazzling array of shapes, colours and behaviours.

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The key to this explosion of evolution

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lies in the cichlids' peculiar breeding behaviour.

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Unlike most fish, which release their eggs into open water,

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cichlids take great care of their young.

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Some sandy bottom species build volcano-shaped nests

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where the male courts his female,

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then guards her brood

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until they have grown big enough to look after themselves.

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Other baby cichlids have a truly bizarre relationship with their mother.

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When threatened, they take shelter in her mouth.

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She then carries them around, waiting until the coast is clear

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before releasing them back into open water.

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Such intensive parenting

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means cichlids often stay in one spot throughout their lives,

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forming inbred communities which turn into unique local species.

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And that explains why Lake Malawi is filled with so many different cichlids.

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For little fish, the rocky lake margin is a dangerous place.

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A family group of African spot-necked otters

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sets out to hunt along the shoreline.

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As night falls, the lake's fish face a formidable enemy.

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Pack-hunting nyanda fish, 1.5m long, behave like sharks,

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using an electrical sense

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to home in on the life signs of smaller fish hiding among the rocks.

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It's thought they can even communicate with electrical signals,

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to synchronise their feeding in the dark.

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For their prey, there's little chance of escape.

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Further from shore,

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Lake Malawi plummets into permanent darkness

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beyond the reach of human divers.

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Until now, no-one has seen what lives down there.

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A remote-controlled sub, armed with camera, lights and fish bait,

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provides the first glimpse of what lies below.

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Over 100m down, the fish bait attracts deepwater cichlids...

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..but their teeth can't get through its armoured skin.

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Attracted by the smell of food - a lake crab.

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In the background, a short-bodied synodontis catfish

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uses its whiskers to investigate the bait.

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Now it's the turn of bathyclarias,

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a deepwater catfish, filmed here for the first time.

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At this depth, the fish bait provides a rare treat.

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The catfish is frantic to feed.

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As the smell of dead fish spreads along the lake bed,

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more crabs are drawn to the scene.

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Eventually the crabs close ranks, forming a barricade of legs and claws...

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..claiming the fish exclusively for themselves.

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Who would have guessed that the Great Rift's lake depths

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are ruled by scuttling crustaceans?

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And what else could be down here?

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Catfish and crabs are only minor players in the Rift's freshwater economy.

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But there's another resident of Lake Malawi that plays a major role

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in the fortunes of the entire region.

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A few days after each new moon during the northern winter months,

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strange tornado-like clouds condense over the lake.

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The phenomenon happens during periods of calm weather,

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allowing the fragile spirals to build hundreds of metres high.

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They consist of vast numbers of tiny midges.

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There may be more midges in a single cloud

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than there are humans on earth.

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All are driven by a single purpose - to breed.

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Absorbed in their dance, the midge clouds drift towards land.

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HIGH-PITCHED BUZZING

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Plants along the shore provide a resting place after hours of constant flight.

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But the vegetation harbours enemies.

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Spiders live along the lake margins in huge mixed colonies.

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Some trap the midges in sticky webs.

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Others use goggle eyes to stalk their quarry,

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pouncing like miniature tigers.

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In spite of countless casualties along the way,

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the majority of the insects eventually return to the lake

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to fulfil their destiny.

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The females lay their eggs on the water surface.

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Then they die.

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The eggs sink...

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..and hatch into translucent aquatic larvae -

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tiny predators which specialise in feeding on lake plankton.

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Enriched with minerals from the surrounding volcanic rocks,

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Lake Malawi's waters support an abundance of plankton,

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which is why the midges are here in such spectacular numbers.

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But the story doesn't end here.

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Sardine-like usipa are voracious predators of midges.

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And these unassuming little fish

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are the key to one last link in this amazing food chain.

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All around the lake, fishermen are launching their dugouts

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in anticipation of a nocturnal uprising.

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Usipa fishing takes place at the new moon,

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when lamps are the only source of light on the lake.

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MEN CONVERSE IN LOCAL LANGUAGE

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Divided between the two larger boats, the net is paid out in a circle.

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At the centre, the lamp-bearing boats draw up the fish to the surface

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like moths to a flame.

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With the bottom rope pulled tight, the trap is sealed.

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Each haul may yield just a few kilos of sardines,

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but the fishermen will land over a dozen catches before dawn.

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MEN CONVERSE IN LOCAL LANGUAGE

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On an island close to the fishing grounds,

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the fishermen grab some breakfast before heading for home.

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ENGINE REVS

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At 2m long, the Nile monitor is Africa's largest lizard -

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an ambush predator armed with raking claws and powerful jaws.

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But why bother to hunt when there's free food on offer?

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HISSES FIERCELY

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As the fishing boats near the shore, a crowd gathers to meet them.

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PEOPLE CONVERSE IN LOCAL LANGUAGE

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In Malawi's hot climate, it's hard to get fresh fish to distant markets,

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so most is spread out to dry in the sun.

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Like this, they will keep for weeks or even months.

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Astonishingly, these tiny usipa provide essential protein

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for around 20 million people in countries bordering the lake...

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..and all this vast bounty originates from tiny fluttering midges.

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From Lake Malawi, the Shire River flows into the mighty Zambezi,

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which marks the southern limit of the African rift system.

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Upstream, the Zambezi

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slices through the volcanic rocks of the Tonga Plateau

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to crash down into the narrow Batoka Gorge.

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More than a mile wide,

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with up to 10,000 tonnes of water pouring over its lip every second,

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this is the world's largest waterfall.

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Its local name, Mosi-oa-Tunya,

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translates as the "Smoke That Thunders".

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In 1855, David Livingstone renamed them Victoria Falls

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in honour of his queen.

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A thousand miles to the north-east, the Rift has another quite distinct arm.

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Here lie lakes very different

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from the vast inland seas of the Western Rift,

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lakes that are hostile to life.

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This is Lake Natron in northern Tanzania,

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sometimes known as the Lake of Death.

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Countless centuries of evaporation

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have concentrated volcanic minerals in its strangely coloured waters

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to the point where they are so caustic they can dissolve human skin.

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However, there is one animal

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that seems immune to this cocktail of corrosive chemicals.

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Each year, huge flocks of flamingos converge on Lake Natron.

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In the shallows,

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the birds demonstrate their unique feeding technique,

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pumping water through hair-fringed channels in their beak

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to extract micro-organisms called cyanobacteria

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which flourish in the lake's peculiar mineral cocktail.

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The cyanobacteria contain a pigment which colours the birds' feathers.

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Adult flamingos only choose mates with colourful plumage,

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so the survival of their species

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is linked to the peculiar chemistry of the rift's volcanic lakes.

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The flamingos are able to wade around in the caustic waters

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because their legs are protected by resistant scales.

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In neighbouring Lake Magadi, life faces an even tougher challenge.

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Fed by volcanic springs,

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Magadi's waters are not only caustic

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but in places they're hot enough to poach an egg.

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Amazingly, there's a creature that's able to survive

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completely submerged in this deadly brew.

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It's a little fish known as the alkaline tilapia.

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And it's made its home in the most extreme environment

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in which fish life has ever been recorded.

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The algae on which the tilapia feed grow best in the volcanic springs.

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So each little fish faces an agonising choice -

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it can stay safe but hungry

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or it can risk life and fin in a dangerous game of chicken,

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dashing into the hot spring, snatching a mouthful of algae,

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then dashing back into cooler water before it cooks.

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Most of the fish are content to hang around the margins of the spring

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but there's always one adventurous or extra-hungry individual

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prepared to go for the jackpot.

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There's no question of the rewards, but it's a hugely risky game.

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140 miles further north along the Great Rift,

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Lake Bogoria is even more volcanically active.

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Its shores are fringed by steam vents and gushing geysers.

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As with Lake Natron, volcanic minerals enrich Bogoria's waters,

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providing an ideal environment for even larger flocks of flamingos.

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At the height of the season, there may be over a million birds.

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FLAMINGOS SQUAWK

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Flamingos are famous for their extraordinary courtship rituals.

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Flamingo migration

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is one of the Great Rift's most enduring mysteries.

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They appear and disappear unpredictably in response to fluctuating water levels.

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Continuing northwards up the Great Rift,

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a series of lakes stretch up through Ethiopia

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to Lake Assal, the saltiest water body on Earth.

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Lake Assal lies 153m below sea level,

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making this the Rift's, and Africa's, lowest point.

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The lake's waters are fed by seawater springs

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which evaporate in the blistering heat to leave huge salt pans.

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Beneath its glistening crust, the lake plunges over half a mile deep.

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But it's not filled with water. It's solid salt all the way to the bottom...

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..the result of hundreds of thousands of years of evaporation.

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Immediately north of Lake Assal is the Mandab Strait,

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known to Arabs as the Gate of Tears.

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It separates Africa from Arabia

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and marks the junction of the Indian Ocean and the Red Sea.

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Here at Ghoubbet el Kharab, barren lava flows

0:42:190:42:22

mark the point at which the Great Rift finally meets the sea

0:42:220:42:26

and enters another world.

0:42:260:42:29

Offshore, the sea floor drops away in spectacular underwater cliffs -

0:42:340:42:40

a submarine equivalent of the Great Rift Valley.

0:42:400:42:43

Strong currents make these walls ideal for filter-feeding corals

0:42:550:42:59

which provide a home for more than a thousand species of fish,

0:42:590:43:04

including over a hundred found nowhere else.

0:43:040:43:08

In the surface waters,

0:43:300:43:32

a school of Indian mackerel trawl open-mouthed

0:43:320:43:35

through the rich plankton.

0:43:350:43:37

There are places off the Djibouti coast

0:43:440:43:47

where the Great Rift plunges to unknown depths.

0:43:470:43:51

Exploring down here takes specialised equipment.

0:43:550:43:59

This is the first time

0:44:560:44:57

light has shone in this corner of the Great Rift's ocean depths.

0:44:570:45:02

Some of the creatures down here may be completely unknown to science.

0:45:050:45:10

From the dark depths of the trench,

0:45:300:45:31

nutrient-rich currents well up towards the surface...

0:45:310:45:34

..creating a plankton bloom that attracts ocean giants.

0:45:370:45:42

Whale sharks are the largest fish on Earth,

0:45:550:45:58

growing over 15m long.

0:45:580:46:01

Trawling the oceans with mouths agape,

0:46:130:46:17

their sieve-like gills sift out the plankton and small fish

0:46:170:46:21

on which they feed.

0:46:210:46:23

Djibouti is famous for this annual gathering of whale sharks

0:46:380:46:41

which migrate here each winter from far across the Indian Ocean

0:46:410:46:45

to take advantage of the Great Rift's fertile waters.

0:46:450:46:50

This extraordinary event owes its existence

0:47:000:47:03

to volcanic forces deep beneath the Red Sea floor.

0:47:030:47:07

Those forces are tearing Africa and Arabia apart.

0:47:130:47:18

As the Great Rift lengthens and widens,

0:47:200:47:23

the Red Sea will eventually join up with the Mediterranean,

0:47:230:47:27

making Africa the world's largest island.

0:47:270:47:31

Meanwhile, the East African Rift continues to spread ever wider,

0:47:330:47:37

gradually filling with lava and ash from the surrounding volcanoes.

0:47:370:47:43

And where seasonal rains refresh the landscape,

0:47:460:47:49

the Great Rift's lakes and rivers

0:47:490:47:53

will continue to sustain an abundance of wildlife.

0:47:530:47:56

HIPPOS GRUNT

0:47:570:48:00

For this episode, the crew discovered

0:48:270:48:30

how harsh the Great Rift can be.

0:48:300:48:31

They call this place "hell on Earth",

0:48:310:48:34

so I guess that's why they send the French Foreign Legion here to train.

0:48:340:48:37

It's a pretty nasty place.

0:48:370:48:40

Cameraman Gavin Newman and director Ingrid Kvale

0:48:410:48:44

found themselves in one of the Rift's hot spots.

0:48:440:48:47

Ow!

0:48:470:48:48

Seems to be the windiest place in Africa

0:48:480:48:50

and I'm having to hold on to the tripod for dear life.

0:48:500:48:53

So on this side I'm in Africa,

0:48:560:48:58

and if I just hop across here, I'm now in Asia.

0:48:580:49:01

No, I'm not. I'm the other way round. Hang on.

0:49:010:49:03

Damn!

0:49:030:49:04

There's one here. Here, here, here. Right beside us.

0:49:050:49:08

The team came here to film what lives in the Great Rift,

0:49:100:49:13

where it plunges beneath the sea.

0:49:130:49:15

Gavin has brought his own specialist kit

0:49:170:49:19

out here to Djibouti in the southern Red Sea.

0:49:190:49:22

Fingers crossed everything does what it says on the tin.

0:49:220:49:25

Gavin has spent the last five years

0:49:300:49:32

perfecting a remotely operated camera system or ROV

0:49:320:49:36

to film underwater much deeper than divers can.

0:49:360:49:39

This is its maiden voyage

0:49:390:49:42

and everyone is understandably nervous.

0:49:420:49:46

You don't want to make a mistake cos you'll pay for it later on.

0:49:460:49:48

I'm a bit of a toy freak at heart.

0:49:520:49:55

Lots and lots of wires, unfortunately.

0:49:550:49:56

Vincente, the boat's dive master, can't wait to put it in the water.

0:49:590:50:03

I think we're going to see landscapes, OK, seascapes,

0:50:040:50:09

that nobody has seen before.

0:50:090:50:10

Captain Amin is intrigued by the machine Gavin has named Nemo.

0:50:110:50:16

How deep you can go with this?

0:50:170:50:20

This can go to about 300m.

0:50:200:50:22

-Whoa.

-Yeah.

0:50:220:50:24

-300m!

-A lot deeper than me.

0:50:240:50:28

Gavin finally fits the ROV with its video camera.

0:50:290:50:34

We'll just give Nemo his eyes.

0:50:340:50:36

The rest of it's a bit of a taxi for this camera system.

0:50:360:50:39

All you have to do now is throw it in the water.

0:50:390:50:42

Tomorrow is Nemo's big day

0:50:420:50:45

and the culmination of Gavin's labour of love.

0:50:450:50:48

At first light, Gavin and the crew head out to the Ghoubbet el Kharab

0:50:540:50:58

or Devil's Cauldron.

0:50:580:51:00

Here, the Great Rift plunges deep below sea level.

0:51:000:51:04

We're at the edge of the wall right now.

0:51:080:51:10

OK. So here it's a good place.

0:51:100:51:12

Jacques Cousteau is said to have come here in search of sea monsters.

0:51:120:51:17

It's a place full of legends -

0:51:170:51:20

legends about spirits living in the small cracks

0:51:200:51:22

that they have in the rocks.

0:51:220:51:24

When Cousteau came here, they put a cage with a camel inside.

0:51:240:51:28

They put it down and when they took it out, the cage was completely crushed,

0:51:280:51:34

no camel inside.

0:51:340:51:36

Did Cousteau say what happened to the camel?

0:51:360:51:38

No explanation.

0:51:380:51:40

So you think this is a good place to dive, then?

0:51:400:51:42

We have to try it.

0:51:420:51:44

It's time for Nemo to get wet.

0:51:470:51:50

INGRID: Are you pleased with that launch, Gavin?

0:51:500:51:52

It was a little bit chaotic but let's just get in and see how it's floating.

0:51:520:51:56

-It's my baby.

-Oh, it's your baby.

0:51:560:52:00

It's looking good.

0:52:020:52:05

Nemo's ready to start exploring the depths of the crack.

0:52:050:52:08

Go, go, go.

0:52:130:52:15

-Wow.

-OK. See where we are.

0:52:150:52:18

So far, so good.

0:52:210:52:23

It's finally underwater and it's finally filming images.

0:52:230:52:26

The beauty of what we're doing

0:52:310:52:32

is that we have no idea what we're going to find anyway.

0:52:320:52:35

It could be we find a huge rift crack

0:52:360:52:40

with all sorts of interesting marine life

0:52:400:52:42

that nobody had any idea was down there.

0:52:420:52:43

But Gavin senses things aren't quite right.

0:52:500:52:53

OK. I think they're pulling me on the cable.

0:52:530:52:56

Can you check what they're doing with the cable?

0:52:560:52:58

They should still be feeding cable.

0:52:580:53:00

VINCENTE: Yeah, they are feeding you cable.

0:53:000:53:02

In that case, we've got a problem and we're stuck.

0:53:020:53:06

At the moment, we might have the cable

0:53:070:53:08

around some rocks on the bottom, but I'm not entirely sure.

0:53:080:53:11

Gavin's suspicions are confirmed.

0:53:120:53:14

The cable is entangled around some rocks.

0:53:140:53:17

Dropping the ROV isn't as straightforward as we thought it'd be.

0:53:190:53:23

There's lots of gnarly bits of volcanic formation

0:53:230:53:27

that could damage or even destroy the ROV.

0:53:270:53:30

Gavin, what do you think?

0:53:300:53:32

Yeah, I'm just a little bit busy right now.

0:53:320:53:36

Vincente dives in immediately to sort the problem.

0:53:360:53:41

-Bring it up. Yeah, please.

-OK, hey!

0:53:410:53:43

Feed cable out. Cable out, yes, into the water.

0:53:430:53:48

Stop. Stop.

0:53:480:53:50

This is not a place to be trifled with.

0:53:500:53:53

There we go. Whoa. That's better.

0:53:560:53:58

OK. We're now looking at the very mouth of the crack here.

0:53:580:54:02

There's an amazing amount of marine life down here.

0:54:050:54:08

It's very diverse as well.

0:54:080:54:10

There's soft corals and hard corals...

0:54:100:54:12

..and a lot of fish.

0:54:140:54:16

There's three cuttlefish here.

0:54:160:54:18

I think we've got a discarded boat's anchor

0:54:200:54:23

that they've obviously lost in the crack.

0:54:230:54:25

A nice bunch of butterfly fish hiding around it.

0:54:260:54:29

Maybe it's Cousteau's anchor - who knows?

0:54:310:54:34

There's several sharks around.

0:54:350:54:38

-He was going towards the Rift.

-Towards the Rift. OK.

0:54:380:54:43

-So if you see something big...

-We know what it is.

0:54:430:54:48

Whale sharks have come here to feed on the plankton at shallow depths.

0:54:480:54:53

This is not a job for Nemo.

0:54:530:54:55

Gavin can't miss out on a chance to film the world's biggest fish

0:54:570:55:01

and puts the ROV filming on hold.

0:55:010:55:04

It's coming towards you. It's there.

0:55:110:55:13

Up there, up there, up there, up there!

0:55:130:55:17

Not one, not two - three, four.

0:55:250:55:28

Whoo! Oh, there's one here, here, here, right beside us.

0:55:280:55:33

-Go!

-I'm trying!

0:55:380:55:40

-INGRID: What's happening?

-It's quite big.

0:55:450:55:47

We've got a bunch of about five whale sharks right ahead of us.

0:55:470:55:50

I think I got five in one shot and you just kept turning around

0:55:550:55:59

and there was another one right behind you.

0:55:590:56:00

There is two swimming side by side.

0:56:000:56:03

Maybe this is a mating ritual.

0:56:030:56:08

After successfully filming whale sharks, Gavin's back with Nemo.

0:56:140:56:19

He's determined to take the ROV deeper than anyone has been before.

0:56:190:56:24

Putting ROVs down holes is never considered to be a great move,

0:56:260:56:31

but obviously you have to take risks to get the sort of images that we want.

0:56:310:56:38

Just got to be careful I don't get stuck here.

0:56:380:56:41

Aah!

0:56:420:56:44

Didn't really want it to end up being Nemo's tomb.

0:56:440:56:47

INGRID: Could this worry be giving you grey hair?

0:56:470:56:51

Yes. I think it's ageing me prematurely, definitely.

0:56:510:56:55

You can see the rift carries on down there, way below us.

0:56:560:57:00

Ah! You've gone quite far if you're down in the middle.

0:57:010:57:04

Yep.

0:57:040:57:05

Just got to hope that I can manoeuvre myself out.

0:57:060:57:08

Ooh, there's a nice little moray eel on the wall. It's beautiful.

0:57:080:57:13

If I turn the lights off altogether, you'll see it's totally dark down here.

0:57:150:57:18

He wondered what happened to the light.

0:57:190:57:22

We're now heading down deep in the crack here.

0:57:240:57:26

It's like a sort of chasm to the bottom of the world.

0:57:300:57:32

So I'll pretty much guarantee you,

0:57:340:57:37

80.3m is the deepest dive anyone or anything has done in the Ghoubbet.

0:57:370:57:41

It's a very strange environment down here

0:57:460:57:48

because most of the creatures that we're looking at

0:57:480:57:50

probably never see light.

0:57:500:57:52

Never really seen anything like this before.

0:57:530:57:55

Looks like lots of skeletal coral.

0:57:560:57:59

Quite pretty. Do you know what that is?

0:58:010:58:03

-This?

-Yes.

0:58:030:58:04

No.

0:58:040:58:05

Nemo's ROV technology has finally revealed

0:58:080:58:12

the strange yet beautiful underwater realm

0:58:120:58:15

that no human eyes have ever seen before.

0:58:150:58:18

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