BBC Africa E05 Sahara
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00:30North Africa.
00:57High in Morocco's Atlas Mountains, Barbary macaques shiver in the icy cedars.
01:14The ancestors of these monkeys fled here from a disaster that overwhelmed their homeland.
01:23Now trapped in this isolated corner of Africa, there's no going back to the land farther
01:29south.
01:33Even in this snowy refuge, there's a reminder of what drove them here.
01:44The unbridled power of the African sun.
01:55Under its intense gaze, the snow can't last for long.
02:06Saltwater should bring life to the lonesome.
02:13Hundreds of torrents cascade southwards, but each is flowing towards extinction.
02:28Just 200 miles south of the mountains, the rivers are vaporized.
02:40Life has been burnt off the land.
02:51This was the apocalypse from which the Barbary macaques fled.
02:57The sudden and unstoppable advance of the greatest desert on the planet.
03:15The Sahara transformed North Africa.
03:19Today, it covers an area the size of the United States.
03:25One third of the entire African continent.
03:33This is one of the hottest places on earth.
03:45The merciless sun, a colossal 15 million degree nuclear reactor, blasted life from the surface
03:53of the land.
03:58It still wreaks havoc.
04:01A faint breath of wind can be the beginning of disaster.
04:47Nomads tell of entire villages being engulfed, camel trains disappearing, and people buried
04:59alive inside their tents.
05:48A sandstorm can be a thousand miles across.
06:00It seems miraculous that anything can survive such devastation.
06:09The Saharan apocalypse wiped out many creatures, but today, some still cling on in the lands
06:17around the margins of the great desert.
06:24It's very dry here.
06:27Some years, the rains fail entirely.
06:34A lone Grevy's zebra.
06:44He weighs close to half a ton and could go for three days without drinking.
06:56Like the macaques, his forebears were refugees from the advancing Sahara.
07:02The land is scrubby and dry.
07:12But this stallion has claimed it as his own.
07:19He's been waiting months for visitors, female visitors.
07:33If they like his territory, they might stay a while.
07:42It's his first chance to mate for a very long time.
08:00Hardly a success.
08:04Perhaps his visitors are looking for a more impressive partner.
08:10There's another setback.
08:14The females were being followed, a posse of young males, every one a rival.
08:27It's time to separate the men from the boys.
08:55One by one, the stallion sees them off.
09:22The females had ringside seats.
09:27And his prowess has not gone unnoted.
09:38Mutismo gives way to tenderness.
09:58And here, you have to take every opportunity, be it for food, for water, or for mates.
10:16Female Grevy's are a fickle bunch.
10:19The herd have decided to move on.
10:23All of them.
10:26The stallion may never see them again, but there's a chance that one is now carrying
10:32his foal.
10:36In this harsh land, that must count as a triumph.
10:49The sun's power cannot, however, reach far underground.
10:56Though in stark contrast, conditions are stable and tolerable.
11:03And home to one of the planet's strangest mammals.
11:11Meet the naked mole rats.
11:20These saber-toothed sausages wouldn't last a day in the desert.
11:27Special filming tunnels allow us to see how well adapted they are to the subterranean
11:31life.
11:33They can run equally well in both directions, so tight space is no problem.
11:43They have lost their fur.
11:47And most bizarrely, they live in social colonies, much like termites or ants.
11:57After time spent digging, the workers come together to relax.
12:13But one here is very different from all the rest.
12:19Their queen, twice as heavy as her subjects, and not afraid to throw her weight around.
12:31She is the mother of every worker in the colony, and exists in a near-continuous state of pregnancy.
12:41And now, two dozen babies are pulsating within her swollen belly.
12:52Just occasionally, one of her brood is raised differently.
12:57A daughter becomes a princess.
13:04Until now, this youngster's enjoyed a lazy, privileged life.
13:09But not for much longer.
13:16She has a destiny to fulfill.
13:27The surface is a place where no naked mole rat can survive for long.
13:34But a princess will risk everything to search for a partner.
13:52The quest is urgent.
14:02There's an enticing smell in the air.
14:14A seductive scent draws her downwards to safety.
14:30She's sniffed out a partner.
14:35He too is alone, and eager to start a new colony in his lonely burrow.
14:44Two months later, the princess has become a queen, and a new tyranny begins.
14:59Tough though they are, such refugees living on the edges of North Africa cannot survive
15:06in the heart of the Sahara.
15:13And yet here, in southern Nigeria, there are creatures preparing to journey right across
15:18the centre of that great desert.
15:26One swallows.
15:36They spent the winter roosting in a forest of elephant grass.
15:41But now it's time for them to leave.
15:50They're tiny, each weighing the same as a couple of one-pound coins.
16:21Yet the journey to their breeding grounds in Europe is over 3,000 miles long.
16:29Ahead of them lies a vast death trap.
16:35The Sahara is too large to go around.
16:39The swallows have no choice but to meet it head-on.
16:55It will take one of nature's greatest feats of navigation to cross this lifeless wasteland.
17:03A wilderness that stretches not just to the horizon, but almost beyond imagination.
17:19It's an immense blank space on the map.
17:30In spite of the Sahara's reputation, less than one-fifth of it is sand.
17:38The rest is stone and wind-scarred rock.
17:52The sun not only bakes the land, it warps its appearance.
18:02The superheated air, rising upward from the desert surface, distorts the distant scene.
18:12A reflection of the sky shimmers on the sands, a mirage.
18:23The sun is an illusionist.
18:30To thirsty travelers, a mirage can resemble a lake which agonizingly recedes as it's approached.
18:45And swaying camels coming to the rescue transform into dry, spiny acacia trees.
19:03To cross this confused, shimmering landscape, many swallows will need to find real water
19:10amongst the mirages.
19:19Even in the Sahara, rain does sometimes fall, and that is sufficient for plants to survive,
19:26providing they have the right adaptations.
19:31Falling from the sand, a dried-out ball of twigs.
19:43In strong winds, it can travel.
20:03This plant may have been dead for a hundred years.
20:10But its name suggests that all is not lost, for this is a resurrection plant.
20:24Around here, rain might only fall once or twice a year, but if you're searching for
20:33decades, that might be enough.
20:43Dead limbs absorb water and unfurl in a matter of minutes.
20:51But the resurrection plant needs one more miracle.
21:02Rain must fall on its branches before they dry out and close up again.
21:32Rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain,
22:02rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain, rain
22:32Then, before they can grow any larger, the sun kills them.
22:48But their seeds live on, ready for when the rains return, even if that is a century from
22:54now.
22:59North Africa wasn't always so brutal. Scattered across the Sahara are glimpses of life before
23:06the apocalypse swept over the land.
23:11In the north, a petrified forest, trees turned to stone, remains from a far distant wetter
23:19past.
23:25White sediments in the heart of the Sahara are the dried-out remains of what was once
23:30the world's largest lake.
23:37In the east, ruined cities hark back to a time of plenty.
23:45And here, deep inside Libya, is Mesak Setafet. Carved here are hundreds of images of animals
24:02all drawn from life, ghosts from a greener time.
24:15Remarkably, a remnant of this old North Africa survives.
24:26Bou Hedma in Tunisia is sustained by mountain rains.
24:36It's a relic of the savannah that once carpeted North Africa.
24:44The vast grassland vanished when a shift in the Earth's orbit drove the rain south.
24:59And in perhaps only a matter of centuries, the Sahara Desert overwhelmed North Africa.
25:07The evidence suggests this took place around 6,000 years ago, in evolutionary terms at
25:15no time at all, and life has had little chance to adapt to this new world.
25:28Only a few tough specialists can cope with life amongst the dunes.
25:36Camels are sometimes called ships of the desert, but like the swallows, they're really
25:57only visitors here. These ships can certainly cross the Sahara, but even they can't make
26:05their home in the harshest places.
26:12Left to wander the desert by themselves, camels would not survive. They depend on their human
26:20navigators to find oases and wells.
26:28Saharan folklore is full of tales of caravans that missed a well by a few hundred metres
26:36and disappeared.
26:44This is the White Desert in Egypt.
27:01The landscape is littered with giant chalk pillars carved by innumerable sandstorms.
27:13This glaring white oven is lethally hot. Food here is almost non-existent.
27:27But there's a rare gift from a passing camel. The smell has lured dung beetles from miles
27:33around. For them, this is manna from heaven.
27:44One dung ball could provide enough food to last this female beetle the rest of her life.
27:54But she has a problem. To keep it fresh, she must bury it in moist ground. And that's not
28:02easy to find.
28:10The temperature has already risen ten degrees.
28:22This lizard avoids the roasting sand. Only thirty centimetres above the surface, it's
28:29significantly cooler.
28:37The reverse pushing technique is certainly the fastest way to keep the ball rolling.
28:48But it does have one drawback.
28:55You can't see where you're going. Disaster. Stuck between two dunes.
29:03The dung ball is twice her weight, but the urge to keep pushing is inextinguishable.
29:11Stuck between two dunes.
29:22The dung ball is twice her weight, but the urge to keep pushing is inextinguishable.
29:40The dung ball is twice her weight, but the urge to keep pushing is inextinguishable.
30:11Now it's 41 degrees Celsius. Soon she'll be baked alive.
30:23Her survival instinct, in the end, overrides her love for dung.
30:41Much of the Sahara is uninhabitable, but there are rare places where there is some possibility
30:47of survival. Places where, by strange chance, there is water.
30:57Wauw Namus is an extinct volcano. From space, it's a remote black scar of the Libyan Sahara.
31:11Yet there are other colours here, colours rarely seen on the desert floor.
31:21Blue and green.
31:29Rain fell thousands of years ago when the Sahara was green and percolated deep into the ground.
31:44And here water, from this vast ancient reservoir, rises to the surface.
31:52These pools offer another glimpse of the Sahara's past.
32:04Wherever there's water in North Africa, living relics from this wetter time have a chance to cling on.
32:12This oasis is fed by a hot volcanic spring.
32:24Slightly away from the stream of near-boiling water, it's cooler, and fish can live. These are tilapia.
32:32Hatchlings stick close to their mother. There are other dangers here, beside the scalding water.
32:45Particularly at night.
33:02The crocodiles are stealthy.
33:14And the tilapia are almost blind in the darkness.
33:23In panic, they all leap to escape the hunter's approach.
33:32But this female can't abandon her brood.
33:45The crocodiles won't be thwarted. They too can leap.
34:02The crocodiles are not afraid of the water.
34:14They are afraid of the water.
34:21They are afraid of the water.
34:26They are afraid of the water.
34:34With first light, the crocodiles lose the element of surprise, and the battle is over for now.
34:43The mother fish has survived, but where are her young?
34:51All present and correct. They spent the whole night sheltering in her mouth.
35:00The contest will be repeated at sunset. There is nowhere else to go.
35:12Oases are always sought by desert travellers, but not all are as they seem.
35:20This is the great Ubare Sand Sea, in the heart of the Sahara.
35:36These swallows have travelled one and a half thousand miles since they left Nigeria.
35:44Their superb powers of navigation will eventually guide them to Europe,
35:49but now they and other thirsty migrants need to find a speck of blue amidst this ocean of sand.
36:01And here it is. Umm al-Ma'a.
36:14Here too, ancient groundwater wells up to the surface.
36:20But the birds need to be careful, for the sun has played a terrible trick.
36:51This oasis is poisonous.
36:57Intense evaporation over thousands of years has left the water saltier than the sea.
37:06As if to underline the horror, the place is infested by vast swarms of flies.
37:14But this plague is the birds' salvation.
37:24The flies are filled with fresh water, filtered from the brine.
37:35So like a desert wanderer squeezing a drink from a cactus,
37:39the birds get all the water they need from the flies' bodies.
37:52More and more migrants join in.
37:57Wagtags.
38:10This is the birds' only stopover.
38:15It gives them enough fuel to escape from the Sahara and Africa.
38:24Away from an oasis, it seems remarkable that anything can live at all.
38:31The temperature of the sands can exceed 70 degrees Celsius.
38:38There's not the slightest trace of water left at the surface.
38:49And when that happens, the Sahara itself cries out.
38:55The Sahara
39:26The Sahara
39:34Billions of sliding grains generate a hum that echoes across miles of empty desert.
39:42These are the Sahara's legendary singing dunes.
39:55The Sahara
40:13Over time, these avalanches add up.
40:20If you watch the dunes for long enough, something remarkable is revealed.
40:28One and a half years flash past in a matter of seconds.
40:41On this timescale, the dunes are like a stormy sea.
40:50An unstoppable tsunami of sand.
41:03In this immense, ever-shifting landscape, it's easy to see how a lost traveller could succumb to what's been called the Sahara's only endemic disease.
41:14Madness.
41:19The Sahara
41:35Can anything survive the North African desert when the sun is at its fiercest?
41:44It's approaching midday.
41:51A fringe-toed lizard is hungry.
41:55He's on a stakeout.
42:05Flashy scales reflect some of the sun's rays.
42:11Nevertheless, the heat is almost unbearable.
42:19His prey hasn't left home all day.
42:25The Sahara
42:35The lizard is the last animal still out on the dunes.
42:44But even he can't take it anymore.
42:48To survive longer, you'd need a spacesuit.
42:55And in a way, that's what these insects have.
43:02Silver ants' armoured skin reflects light.
43:07They can tolerate temperatures that would kill any other land animal.
43:13Even so, they can only survive for less than ten minutes in the midday sun.
43:26Time is precious.
43:30The ants race to find food as soon as their predators go to ground.
43:43They can't afford to waste a second getting lost, so they spin to take a bearing from the sun.
43:52They log every change of direction, every footstep, in order to know exactly where they are and where their nest lies.
44:05Only four minutes to spare and they've found a victim of heatstroke.
44:11A meal.
44:15But it's going to take a monumental effort to get it home.
44:33Three minutes to go and they're nearing their maximum temperature, an astounding 53 degrees Celsius.
44:46But there are already casualties.
45:01One minute left and they're not going to make it. Something has to change.
45:15They're going to have to do it.
45:19They're going to have to do it.
45:23They're going to have to do it.
45:27They're going to have to do it.
45:31They're going to have to do it.
45:35They're going to have to do it.
45:39They're going to have to do it.
45:44They're going to have to do it.
45:54The silver ant is the hardiest of all desert inhabitants.
46:00Even so, it can only survive outside in the middle of the day for a matter of minutes.
46:07Now, the desert belongs to the sun alone.
46:16The sun has scorched life from the Sahara,
46:21and yet the vast desert it created is a source of life half a world away.
46:28The advancing Sahara vaporised the world's largest lake,
46:34leaving behind the silvery remains of countless microscopic algae.
46:42In winter, the wind carries away 700,000 tonnes of this mineral-rich dust every day.
46:51It blows from here all the way to South America,
46:55where, astonishingly, it fertilises the Amazon rainforest.
47:07A striking demonstration of the reach of this mighty continent.
47:14Throughout its long history, Africa has influenced the entire planet.
47:20It was the cradle of a remarkable array of land animals that spread across the globe,
47:26and, of course, it was the ancestral home of all of us.
47:30It was the cradle of a remarkable array of land animals that spread across the globe,
47:36and, of course, it was the ancestral home of all of us.
47:40And, of course, it was the ancestral home of all of us.
48:11This is the tale of two of the Africa team's most challenging desert expeditions.
48:23One focused on a minuscule creature with an incredible turn of speed.
48:30The other on a subject so slow to film it in action would take years.
48:35In both cases, the Sahara would push crews to the limit in pursuit of the perfect shot.
48:47In Tunisia, the mission is to capture footage of moving sand dunes,
48:51something that's never been tried like this before.
48:55The problem is that because the genes move so slowly,
48:57we're going to have to leave cameras here for about 20 months,
48:59and that just means there's a huge potential for things to go wrong.
49:02And with filmmaking, if something can go wrong, it usually will.
49:08Two local shepherds, Amour and Nasser, have volunteered to tend the equipment full-time.
49:17The camera tower will be the tallest structure for as far as the eye can see.
49:26And there are three other cameras,
49:29and there are three other cameras at lower angles.
49:34All this toil will yield surprisingly scant results.
49:39They've programmed the cameras to take one photo every day.
49:43That's only 365 photographs a year,
49:46which when you run it at normal speed, just over 14 seconds.
49:50I think it's taking longer to explain what's going to happen.
49:56And the end result will actually be...
49:58The cameras are left to the mercy of the sun, wind and sand.
50:04In the meantime, crews are shooting all across North Africa.
50:11In Egypt, the challenge is to get into the world
50:14of the most heat-tolerant desert animal, the silver ant.
50:18They're really small, they move really fast.
50:21Like, you're not too sure if you've seen an ant before.
50:24You're not too sure if you've seen an ant.
50:28The crew have three weeks to gather the footage they need.
50:33We're going to try a tracking shot on this ant nest,
50:36moving forward towards it
50:38as the ants pour out of the hole in their millions.
50:43Not only are these insects super-fast, they also keep antisocial hours.
50:49The thing is, we need to be out here in the middle of the day to film these ants.
50:53They don't do what they do, and it's nice and cool at 7, 8 o'clock in the morning.
50:59I can't remember ever being in a place where the wind was so relentless
51:02and the temperatures were so high.
51:08The insufferable heat is not the only problem.
51:11Dangers are everywhere.
51:15There's a really fat scorpion. It's really big.
51:19One, two, three.
51:21What's up?
51:25This might kill.
51:26Yeah?
51:27Yeah.
51:29It's big and they have a lot of poison in his dark thing.
51:32What, that thing there?
51:33Is it?
51:34Oh, my God!
51:36Don't touch it!
51:38The scorpion will be released far, far away from the camp in a shady spot.
51:44No such luck for the team.
51:46They're back to work in the midday sun.
51:49This is, this is too much.
51:52This is crazy.
51:54This is crazy.
51:55Indeed.
51:56The heat seems to have given Captain Warwick a touch of Saharan madness.
52:02The plan is to do an experiment.
52:05Find out how fast these little ants can run.
52:10So we're going to lay this along the floor and hopefully an ant will run alongside it
52:15and we can film it at high speed.
52:17And from that, calculate their speed and perhaps try and relate it to how fast that would be for a human.
52:25Like me.
52:27Silver ants are expert navigators, using the angle of the sun to calculate their position.
52:32But for our team, even basic mental tasks are becoming a challenge.
52:38Count a second. When you see one running, don't count a second.
52:41It's quite difficult to count a second, isn't it?
52:43No, it's one.
52:47One.
52:48Yeah.
52:53There he goes.
52:57He's gone 10 centimetres in four seconds.
52:59Yeah.
53:00But we're running at 500 frames per second, which is 20 times normal time.
53:05Yeah.
53:06So in fact, he's covered those 10 centimetres in...
53:13We know that he does half a metre in one second.
53:16Half a metre per second, yeah.
53:1950 centimetres in one second.
53:21Yeah.
53:22Roughly.
53:23So how many body lengths is that?
53:27He's maybe doing five body lengths a second if he's two metres tall like I am.
53:31Are you?
53:32Yeah. That's so much more than a normal man I am.
53:35Eventually, the duo decide that if the silver ants were our size,
53:40they'd be doing 280 miles an hour.
53:47They're one of the fastest sprinters in the animal kingdom.
53:51They're ones we've been struggling to film.
53:53It does explain a few things.
53:57Antletics.
53:59Knowing the exact speed of the ants is all well and good,
54:01but there's still a great deal of work to be done before the shoot finishes.
54:07However, in Tunisia, there's no shortage of time,
54:11and hopefully no news is good news, as far as Amur and Nasser are concerned.
54:19The next day.
54:20The next day.
54:21The next day.
54:22The next day.
54:23The next day.
54:24The next day.
54:25The next day.
54:26The next day.
54:28The final week in Egypt,
54:31and the crew seem to be adapting to life in the oven.
54:38Practice is making perfect, and the sequence is coming together.
54:46I think we've got some lovely shots.
54:48Every single shot's been really hard-earned.
54:50But getting down in the ants' world is now taking its toll on the kit.
54:54It's running to stand still, the business of blowing dust off these things.
55:01Oh, no.
55:02It's got dust in it.
55:05Oh, crunch.
55:09I think these ants are stunning-looking.
55:11Near impossible to film, I think, because of the speed they had.
55:14But, you know, I've come to love them over the days and weeks.
55:20With the sequence in the bag,
55:22Warwick wants the final traditional sunset shot.
55:26It's the best time of day to film sunset in the evening.
55:31That's experience that tells me that I've been doing this for years.
55:34You learn these things.
55:36Thanks to Warwick's experience, including sunsets,
55:39he and Kat have captured the extraordinary life of the speedy silver ant.
55:48Over a year later,
55:50Over a year later, in Tunisia,
55:52it's time to take down these sand dune cameras.
55:57Bonjour.
56:00Amor.
56:02Hi. Hello again.
56:03So, how's it been? Has it been good?
56:05It's OK, but two days ago, we have a little bit small problem.
56:10After surviving 600 days in the desert,
56:13the small problem is that the cameras have been vandalised.
56:18I'm really hot and bothered now. It's 40 degrees.
56:21And someone smashed the cameras.
56:24Not been a good start to the day, to be honest.
56:28There's no doubt the dunes have moved,
56:30but the question is whether the equipment has survived.
56:37That is amazing, the camera's still here.
56:39I guess I maybe just took them so long to get through the tough on plastic
56:43I guess I maybe just took them so long to get through the tough on plastic
56:46that they felt that they'd made so much noise
56:48they were worried about the guards coming
56:50because they only sleep a couple of hundred metres away.
56:53After almost two years of waiting, it's the moment of truth.
57:00We're going to find out.
57:01We're going to find out whether or not the cameras have actually recorded anything.
57:06It's just hugely stressful because it's never been done before.
57:10The footage is a surreal window into a secret world,
57:14the private life of a sand dune.
57:27The Africa team struggled under the burning sun and driving winds
57:31at the hallmarks of the Sahara.
57:40They went home with an enormous admiration for the creatures
57:44that spent their entire lives battling to survive in this brutal desert world.
58:09To find out more, visit www.sanddune.co.uk