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All habitats present challenges to life,

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but few more so than the desert.

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(wind blowing)

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The hottest, driest, most hostile landscapes

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seem foreboding to us.

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(gentle music)

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The conditions can be deadly,

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but still a hardy band of unique animal and plant species

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have adapted to face the challenges head on.

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From cactus to camels,

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to hedgehogs,

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and even humans.

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Each one finds its own ways

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to exploit and conserve food and water

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in its daily struggle for survival.

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(waves whooshing)

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Deserts are a huge part of our planet,

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but they are getting bigger and harsher because of us.

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Thankfully, it doesn't take much to give them a hand

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and to reveal the enduring treasures of the desert.

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(gentle music)
(insects chirping)

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You might expect to find deserts

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around the center of the Earth, the equator,

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the part of the planet closest to the sun

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and exposed to its most direct rays.

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But instead, the equator has a band of rainforest.

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On this hottest part of the globe,

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the sun heats the ground,

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and from it hot air rises.

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When it gets higher, the air cools,

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and rain falls,

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keeping the forest well watered

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and under the protected cover of clouds.

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(rain whooshing)
(thunder booming)

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(gentle music)

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Once the rain has fallen,

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the dry air is pushed out to the sides

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by more hot air rising below.

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It falls 15 to 30 degrees north or south of the equator.

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And this is where most of the world deserts are formed.

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Like the biggest, the Sahara.

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The largest hot desert,

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almost as big as the United States,

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the Sahara straddles many countries across Northern Africa.

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Much of the region is a sea of sand

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punctuated by dramatic shifting dunes,

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some more than 150 meters tall.

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The Sahara is consistently one of the hottest places,

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typically over 40 degrees,

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which makes it hard for life.

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(wind whooshing)
(dramatic music)

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But there are some tough inhabitants.

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There's an aray of small animals,

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(gentle music)

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making up the base of the food chain.

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Even the thin-skinned European green toad

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can eek out a living by lurking in the shadows.

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(fox sniffing)

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Dune beetles have rich bodies

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to collect and channel the morning dew into their mouths,

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making them the perfect water source

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for this little predator,

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the smallest member of the dog family.

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(wings flapping)

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The fennec fox might be tiny,

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but its ears are anything but.

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(wings flapping)

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They are an adaption,

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increasing the surface exposed to any breeze

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to help him lose heat.

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(fox flapping)

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His thick coat is sandy,

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not only for camouflage

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but pale to reflect the sun by day

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and thick to keep him warm at night.

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And hairy feet stop this little fox

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from scolding his toes on the baking sand.

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(fox sniffing)

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With these adaptations, the fennec fox can thrive,

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and comfortably forage among the dunes.

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(fox munching)

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(gentle music)

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At first glance,

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there isn't much animal life in the desert.

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But that's because of the temperature.

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To beat the heat,

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most creatures wait for the cool of night.

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(insects chirping)

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Specially on the scolding plains of Australia.

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(lively music)

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Spinifex mice are more comfortable exploring

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under the cover of darkness.

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In most areas,

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coldblooded lizards like to bask in the sun's heat

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to fuel their bodies.

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But here, many are more active at night.

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(tense music)

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The knob-tailed gecko is no threat to the mice.

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(gentle music)

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But it could be in trouble

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when a mouse lookalike starts foraging.

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It might look like a little rodent,

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but the fat-tailed dunnart isn't at all related.

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It's a marsupial,

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a tiny cousin of the ferocious Tasmanian devil.

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The little guy's about the length of your thumb,

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but that doesn't deter his carnivorous confidence.

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Though luckily for the gecko,

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he's after crickets tonight.

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(fat-tailed dunnart munching)

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As the sun appears on the horizon,

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these creatures will seemingly vanish,

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retreating to their burrows.

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And a new cast appears.

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(wind blowing)
(gentle music)

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Some animals are crepuscular,

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meaning they are most active at dawn and dusk.

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This time in the vast sways of desert

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that straddle Central Europe.

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A quick sniff and her nose tells her

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it's safe to leave her den.

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When you are as small as a long-eared hedgehog,

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it pays to be careful.

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She begins her daily foraging trip

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across the sand dunes of her home

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in the deserts that straddle Central Eurasia.

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She's looking for breakfast

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and hoping to find it before the sun bakes the sand

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until it's too hot to touch.

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She's a fan of little creatures.

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70% of her diet is crunchy insects

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that will give most of the moisture she needs.

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She's not the only one looking for a bite.

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A toad-headed agama is basking

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in the relative cool of the morning.

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He watches the competition.

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Until she gets a bit close.

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(dramatic music)

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He transforms himself into a movie alien.

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Lipids are umbrella-like flaps of skin

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he can expand to freak out would-be attackers.

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Finding enough food in the desert is tough.

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Neither has time to worry about the other.

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(gentle music)

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Though breakfast for either of them might be off.

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(wind blowing)

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In the desert, sandstorms can be sudden and severe.

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(wind blowing)

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The lizards has a neat trick.

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A quick shimmy and he's buried enough

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to shelter from the storm.

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The hedgehog wisely retreats to her burrow.

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This is a typical day for creatures of the desert.

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Trying to beat the heat, find food,

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and survive the weather

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in one of the most hostile environments on the planet.

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(wind blowing)
(gentle music)

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Deserts can be found on every continent

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and cover 1/5 of the Earth's surface.

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They are defined

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as receiving less than 25 centimeters of rain a year.

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And crucially lose more moisture to evaporation

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than they gain from rain.

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Because there's little wetness,

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they don't get many clouds,

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so temperatures get very cold at night,

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often below freezing.

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And exceptionally hot during the day,

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50 degrees centigrade or more.

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We typically imagine deserts as sandy,

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but they can be rocky too.

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(elephant trumpets)

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Usually without much vegetation because of the conditions

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and without plant roots to stabilize soils,

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the earth blows away, revealing sand,

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gravel and rocks.

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(gentle music)

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Sometimes offering windows on long lost landscapes.

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The bizarre pillars of rock in the Pinnacles Desert

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in Western Australia

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are made from the remains of tiny shellfish,

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indicating that this area was once ocean.

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No one is too sure what carved the strange structures.

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(birds chirping)

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It might have been minerals leaching into the soil

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and cementing them.

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Or the boring roots of long lost trees

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might have compacted the ground and created entry points

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where eroding rain water could seep in.

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Either way, there are no trees now,

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so the galahs have to make due

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with nesting on the pillars instead.

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The otherworldly landscape seems a far cry

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from its ocean origins.

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(waves whooshing)

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Though water and deserts

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are not things we associate together,

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some deserts are actually found on the coast.

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It's the ocean itself that causes them.

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Cold water currents,

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in this case the Benguela,

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bring water from the poles to warmer climates.

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The cold water below makes the sky shed its water

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as rain or mist

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before it reaches the coast,

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leaving dry areas in land.

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Coastal deserts.

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This one is the Namib,

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the oldest desert on the planet.

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It's been arid for at least 55 million years.

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(wind blowing)

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The landscape has been thwarted on both sides

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by its geography.

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Trade winds blow across Southern Africa from the east.

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But when they hit the Drakensberg Mountains,

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thrusting them skywards,

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the air cools and moisture droplets form.

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(wind blowing)

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(thunder booming)
(rain whooshing)

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The mountains get rainfall,

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but the deserts beyond get nothing but hot dry winds.

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And to the west,

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the cold ocean claws back the moisture too.

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(seals barking)

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But there is one benefit.

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The cold air of the coast meeting the warmth of the desert

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causes a regular bank of fog,

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a hint of moisture that drawls in across the dunes.

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(gentle music)

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Just enough to feed desert specialist plants

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like these Lithops,

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aptly nicknamed living rocks.

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Living close to the ground,

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these plants aren't exposed to the drying winds.

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There's not much of the plant above ground,

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but to help their few leaves

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gather enough sun for photosynthesis,

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their surface is see-through.

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They're succulents, storing water in their chunky leaves.

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Despite the tough conditions,

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the plants can be hardy and long-lived.

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The Welwitschia, sometimes called a living fossil,

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is only found in the Namib Desert.

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But despite this hostile environment,

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individuals survive for thousands of years.

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(insects chirping)

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All the plants are living water stores

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for a surprising wealth of wildlife.

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Gemsbok, like many of the animals here,

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have adapted to survive

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without access to water for weeks on end.

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(gentle music)

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They get what they need from the plants.

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To conserve this most precious desert resource,

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they don't sweat to cool down,

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instead allowing themselves to overheat.

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Their bodies can reach 45 degrees centigrade,

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which is hot enough to cause brain damage in most animals.

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But they cope thanks to a network of blood vessels

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that carry the excess heat away from their brain.

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There's not a huge diversity of large animals here.

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The desert is too tough for most.

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But the gemsbok are joined by ostrich.

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Springbok.

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And a few zebra.

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(zebras thumping)

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Giraffes even manage to make a living here.

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They can only cope where there are enough acacia trees.

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Their long highly-mobile lips

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help them pick out tiny leaves

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from between the plant's thorny defenses.

272
00:21:00,600 --> 00:21:04,940
The giant trees seem to live in the absence of water,

273
00:21:04,940 --> 00:21:06,953
but the desert can deceive.

274
00:21:10,670 --> 00:21:13,960
While the Namib lacks any surface water,

275
00:21:13,960 --> 00:21:16,600
there are rivers that run deep underground,

276
00:21:16,600 --> 00:21:20,470
and along their course the trees are able to make a living

277
00:21:20,470 --> 00:21:24,240
using exceptionally long roots to boar down into the ground

278
00:21:24,240 --> 00:21:25,563
and extract moisture.

279
00:21:26,602 --> 00:21:29,860
(elephant trumpets)

280
00:21:29,860 --> 00:21:31,500
Thanks to their efforts,

281
00:21:31,500 --> 00:21:34,203
other animals get a little moisture from their leaves.

282
00:21:41,240 --> 00:21:44,983
It's even enough to sustain the biggest animals on Earth.

283
00:21:55,593 --> 00:21:58,360
And the trees form the rare luxury of cool shadows

284
00:21:58,360 --> 00:22:00,653
that creatures of all sizes can enjoy.

285
00:22:11,290 --> 00:22:14,840
Plants really define the success of whole food chains

286
00:22:14,840 --> 00:22:17,373
and they are masters at adaptation.

287
00:22:21,170 --> 00:22:23,510
The plants vary just as much as the animals

288
00:22:23,510 --> 00:22:26,071
from one region to the next.

289
00:22:26,071 --> 00:22:28,420
(bird craws)

290
00:22:28,420 --> 00:22:31,920
North America has four main deserts.

291
00:22:31,920 --> 00:22:34,640
The Great Basin is high elevation,

292
00:22:34,640 --> 00:22:37,263
meaning that it gets harsh winters.

293
00:22:38,117 --> 00:22:40,700
(gentle music)

294
00:22:47,860 --> 00:22:49,410
Rather than rain,

295
00:22:49,410 --> 00:22:52,533
the little moisture it receives falls as snow.

296
00:22:56,450 --> 00:22:58,543
The plants here are not succulents.

297
00:23:01,220 --> 00:23:02,590
Instead, they are dominated

298
00:23:02,590 --> 00:23:05,353
by the small-leafed and hardy sagebrush.

299
00:23:10,850 --> 00:23:13,010
The tough plants are enough to sustain

300
00:23:13,010 --> 00:23:14,973
one of the larger desert animals.

301
00:23:17,070 --> 00:23:17,987
Pronghorns.

302
00:23:22,590 --> 00:23:23,770
Almost all of their water

303
00:23:23,770 --> 00:23:26,193
comes from the leaves of these tough plants.

304
00:23:30,460 --> 00:23:32,340
Often called antilope,

305
00:23:32,340 --> 00:23:34,470
the graceful creatures are the last members

306
00:23:34,470 --> 00:23:37,383
of a unique family of fleet-footed grazers.

307
00:23:42,760 --> 00:23:46,870
For their cold desert home, they need a thick coat,

308
00:23:46,870 --> 00:23:50,610
but at the same time must cope with extreme heat,

309
00:23:50,610 --> 00:23:52,930
so they can rise the hair on their backs,

310
00:23:52,930 --> 00:23:54,733
allowing hot air to escape.

311
00:23:57,906 --> 00:24:00,489
(gentle music)

312
00:24:01,370 --> 00:24:03,683
There are few trees out here on the plains,

313
00:24:04,620 --> 00:24:06,873
the usual places for birds to nest.

314
00:24:09,320 --> 00:24:12,500
But burrowing owls live up to their name,

315
00:24:12,500 --> 00:24:14,333
raising their families underground.

316
00:24:23,160 --> 00:24:24,440
It also gives them a place

317
00:24:24,440 --> 00:24:26,973
to escape the fierce desert temperatures.

318
00:24:39,400 --> 00:24:42,543
While most of North America's deserts get harsh winters,

319
00:24:45,700 --> 00:24:47,283
the Sonoran does not.

320
00:24:50,050 --> 00:24:51,850
Hot year round,

321
00:24:51,850 --> 00:24:54,800
the Sonoran straddles five US states

322
00:24:54,800 --> 00:24:56,793
and a chunk of Northwestern Mexico.

323
00:24:59,540 --> 00:25:02,720
Over 200,000 square kilometers of heat

324
00:25:02,720 --> 00:25:04,920
dominated by the most unique

325
00:25:04,920 --> 00:25:08,563
and iconic desert plants, cactus.

326
00:25:14,900 --> 00:25:17,330
With nearly 2,000 species,

327
00:25:17,330 --> 00:25:21,253
these hardy plants can range from minute to mega.

328
00:25:24,510 --> 00:25:26,173
Up to 20 meters tall,

329
00:25:28,770 --> 00:25:31,553
they are living water towers.

330
00:25:31,553 --> 00:25:34,220
(thunder booms)

331
00:25:35,518 --> 00:25:37,000
(cactus thuds)

332
00:25:37,000 --> 00:25:40,763
Up to 90% of their weight can be the water stored within.

333
00:25:47,630 --> 00:25:49,380
Though some have long tap roots

334
00:25:49,380 --> 00:25:51,540
to reach deep water sources,

335
00:25:51,540 --> 00:25:54,830
most have very shallow but wide-spanning roots

336
00:25:54,830 --> 00:25:56,360
close to the surface

337
00:25:56,360 --> 00:25:59,907
to soak up any rain that falls before it can evaporate.

338
00:26:00,753 --> 00:26:05,753
(gentle music)
(rain whooshing)

339
00:26:10,610 --> 00:26:13,890
Their thick waxy skins can reflect the sun

340
00:26:13,890 --> 00:26:17,123
and seal the surface of their leaves to reduce water loss.

341
00:26:19,540 --> 00:26:22,390
Because water is stored in their leaves

342
00:26:22,390 --> 00:26:26,320
and water is the most sought-after resource in the desert,

343
00:26:26,320 --> 00:26:29,530
the cacti need to defend themselves,

344
00:26:29,530 --> 00:26:32,963
otherwise every animal would be raiding their supplies.

345
00:26:34,598 --> 00:26:36,190
(bright music)

346
00:26:36,190 --> 00:26:40,760
So their soupy water inside is bitter to deter drinkers,

347
00:26:40,760 --> 00:26:43,560
though most never get through the first line of defense.

348
00:26:47,360 --> 00:26:49,510
Their famous spines are actually

349
00:26:49,510 --> 00:26:51,943
the plants' highly-modified leaves.

350
00:26:53,740 --> 00:26:56,210
Having normal leaves would increase the surface area

351
00:26:56,210 --> 00:26:57,560
of the plant

352
00:26:57,560 --> 00:27:00,333
and the amount of water lost to evaporation.

353
00:27:03,900 --> 00:27:07,630
Small hair-like spines can also trap a layer of air

354
00:27:07,630 --> 00:27:09,590
close to the plant's skin,

355
00:27:09,590 --> 00:27:12,490
creating a microclimate above her

356
00:27:12,490 --> 00:27:16,003
against the extreme heat of the day and cold of the night.

357
00:27:19,527 --> 00:27:22,527
(squirrel munching)

358
00:27:27,409 --> 00:27:28,950
(gentle music)
Like most plants,

359
00:27:28,950 --> 00:27:32,290
the cactus photosynthesize to produce food,

360
00:27:32,290 --> 00:27:35,150
which involves the intake of carbon dioxide

361
00:27:35,150 --> 00:27:36,973
and the output of oxygen.

362
00:27:41,630 --> 00:27:43,400
Plants have stomata,

363
00:27:43,400 --> 00:27:45,870
little breathing holes all over their skin,

364
00:27:45,870 --> 00:27:48,023
for this gas exchange to take place.

365
00:27:53,810 --> 00:27:58,370
But cacti keep their stomata closed during the day,

366
00:27:58,370 --> 00:28:01,450
opening only at night to let out oxygen

367
00:28:01,450 --> 00:28:03,750
and take in carbon dioxide

368
00:28:03,750 --> 00:28:07,060
which is then stored until the sun comes out

369
00:28:07,060 --> 00:28:09,433
and photosynthesis can take place.

370
00:28:10,900 --> 00:28:13,817
(insects chirping)

371
00:28:16,870 --> 00:28:19,830
Thanks to this unusual nocturnal behavior,

372
00:28:19,830 --> 00:28:23,823
cactus can reduce water loss through these pores by 90%.

373
00:28:24,938 --> 00:28:27,560
(animal screeching)

374
00:28:27,560 --> 00:28:30,310
It's not just plants making the most of the cool night.

375
00:28:31,990 --> 00:28:34,350
Not a werewolf howling at the moon.

376
00:28:34,350 --> 00:28:37,293
In fact, not a very threatening-looking creature at all.

377
00:28:40,030 --> 00:28:43,913
But the grasshopper mouse is a predator through and through,

378
00:28:45,280 --> 00:28:48,650
and its quarry some of the most poisonous creatures

379
00:28:48,650 --> 00:28:50,891
that inhabit the desert.

380
00:28:50,891 --> 00:28:53,391
(tense music)

381
00:28:57,361 --> 00:29:02,194
It has a powerful bite to snip off the scorpion's weapons.

382
00:29:08,210 --> 00:29:12,593
But also a resistance to the arachnid's usual lethal venom.

383
00:29:14,900 --> 00:29:17,760
In the Sonoran Desert of North America,

384
00:29:17,760 --> 00:29:20,520
in the ankle-high animal community,

385
00:29:20,520 --> 00:29:22,683
the grasshopper mouse reigns supreme.

386
00:29:24,115 --> 00:29:26,865
(dramatic music)

387
00:29:39,340 --> 00:29:42,257
(mouse screeching)

388
00:29:48,535 --> 00:29:51,452
(insects chirping)

389
00:29:55,530 --> 00:29:59,510
A barking gecko out strolling in the dark African desert

390
00:29:59,510 --> 00:30:01,333
is a bit alarmed by his neighbor.

391
00:30:02,204 --> 00:30:04,787
(gentle music)

392
00:30:08,500 --> 00:30:11,370
Though he might occasionally nibble a little lizard,

393
00:30:11,370 --> 00:30:14,573
the porcupine would much prefer a plate of greens.

394
00:30:22,420 --> 00:30:24,890
He's one of the biggest rodents in the world

395
00:30:24,890 --> 00:30:27,530
and well-armed against the many large predators

396
00:30:27,530 --> 00:30:28,763
of the African bush.

397
00:30:34,490 --> 00:30:38,060
But he's not so well-protected against the desert sun,

398
00:30:38,060 --> 00:30:40,350
so when the sun begins to rise,

399
00:30:40,350 --> 00:30:41,883
he'll head back to his burrow.

400
00:30:48,700 --> 00:30:51,333
Some of his neighbors have the opposite strategy.

401
00:31:02,550 --> 00:31:05,800
Meerkats are not built for cold temperatures

402
00:31:05,800 --> 00:31:07,803
and huddle through the night in burrows.

403
00:31:13,190 --> 00:31:15,477
(gentle music)

404
00:31:15,477 --> 00:31:19,310
When the sun rises, they head out to greet it.

405
00:31:30,360 --> 00:31:34,070
Most mammals maintain even temperature at all times,

406
00:31:34,070 --> 00:31:36,240
but meerkats allow their bodies

407
00:31:36,240 --> 00:31:39,733
to warm during the day and cool during the night.

408
00:31:41,670 --> 00:31:44,390
To help them bounce back from their chilly slumber,

409
00:31:44,390 --> 00:31:45,767
the family sunbathes.

410
00:31:52,210 --> 00:31:53,770
As it gets hotter,

411
00:31:53,770 --> 00:31:56,520
they will take the baking temperatures in their stride,

412
00:31:57,760 --> 00:31:59,223
foraging for breakfast.

413
00:32:00,910 --> 00:32:02,780
The real treat this morning,

414
00:32:02,780 --> 00:32:04,660
like the grasshopper mouse,

415
00:32:04,660 --> 00:32:06,893
meerkats are scorpion slayers.

416
00:32:07,797 --> 00:32:10,964
(meerkats screeching)

417
00:32:19,390 --> 00:32:21,810
The ground squirrels that live alongside them

418
00:32:21,810 --> 00:32:23,710
need a little bit of help in the heat.

419
00:32:36,511 --> 00:32:39,640
(gentle music)

420
00:32:39,640 --> 00:32:43,460
(squirrel munching)

421
00:32:43,460 --> 00:32:47,020
They raise their tails, built-in parasols,

422
00:32:47,020 --> 00:32:48,923
to offer a bit of portable shade.

423
00:33:00,740 --> 00:33:03,740
(squirrel munching)

424
00:33:09,610 --> 00:33:12,693
They have another way to chill when the going gets tough.

425
00:33:14,100 --> 00:33:17,763
They dig to expose cooler sand beneath the surface.

426
00:33:35,130 --> 00:33:37,443
Then they can lay back and enjoy.

427
00:33:49,310 --> 00:33:51,280
In her Eurasian desert,

428
00:33:51,280 --> 00:33:53,897
the long-eared hedgehog is out and about.

429
00:34:01,160 --> 00:34:03,833
She ignores the herds of delicate gazelles.

430
00:34:08,190 --> 00:34:10,900
They can cope with extreme temperatures

431
00:34:10,900 --> 00:34:13,150
but prefer to get most of their hard work done

432
00:34:13,150 --> 00:34:14,453
before things heat up.

433
00:34:17,920 --> 00:34:21,350
Dawn is the best time for the hedgehog to forage.

434
00:34:21,350 --> 00:34:23,430
It's when most animals are active,

435
00:34:23,430 --> 00:34:25,083
before the day gets too hot.

436
00:34:27,430 --> 00:34:29,723
This time, she gets lucky.

437
00:34:32,090 --> 00:34:35,363
There is just enough food to sustain her little body.

438
00:34:39,477 --> 00:34:42,060
(gentle music)

439
00:34:46,530 --> 00:34:49,290
Big animals are scarce in the desert.

440
00:34:49,290 --> 00:34:51,040
Few have what it takes to cope

441
00:34:51,040 --> 00:34:53,040
with the huge shifts in temperature

442
00:34:53,040 --> 00:34:54,233
and the lack of water.

443
00:34:55,730 --> 00:35:00,730
Apart from the most iconic desert giant, the camel.

444
00:35:08,730 --> 00:35:12,140
With tough mouths to cope with the dry vegetation,

445
00:35:12,140 --> 00:35:15,060
long eyelashes and closable nostrils

446
00:35:15,060 --> 00:35:17,193
to keep out the ever-blowing sands.

447
00:35:22,110 --> 00:35:25,983
The ability not to lose much water through sweat or urine.

448
00:35:28,280 --> 00:35:31,623
Broad feet to spread their weight on sandy dunes.

449
00:35:33,090 --> 00:35:36,360
And of course their most famous humps,

450
00:35:36,360 --> 00:35:39,800
fat stores that can be broken down to water and energy

451
00:35:39,800 --> 00:35:41,723
when they fall on hard times.

452
00:35:44,310 --> 00:35:46,160
Dromedary camels like these

453
00:35:46,160 --> 00:35:50,110
once roamed across much of North Africa and Western Asia,

454
00:35:50,110 --> 00:35:52,071
but for the last 2,000 years

455
00:35:52,071 --> 00:35:54,103
they have been extinct in the wild.

456
00:35:55,680 --> 00:35:57,940
And that's because of a unique relationship

457
00:35:57,940 --> 00:36:00,477
that formed some 4,000 years ago.

458
00:36:03,120 --> 00:36:05,573
The camel was domesticated.

459
00:36:06,410 --> 00:36:09,050
While wild cousins were hunted or interbred

460
00:36:09,050 --> 00:36:10,910
with the domestic animal,

461
00:36:10,910 --> 00:36:13,283
the captive herds grew to take their place.

462
00:36:15,330 --> 00:36:18,550
They made it much easier for another species of large mammal

463
00:36:18,550 --> 00:36:20,492
to make a living here.

464
00:36:20,492 --> 00:36:23,242
(fire crackling)

465
00:36:24,230 --> 00:36:25,163
Humans.

466
00:36:27,129 --> 00:36:29,879
(water sloshing)

467
00:36:31,020 --> 00:36:34,080
There are a number of human populations

468
00:36:34,080 --> 00:36:36,430
who have adapted to desert life,

469
00:36:36,430 --> 00:36:37,723
such as the Bedouins.

470
00:36:41,670 --> 00:36:44,060
A nomadic lifestyle has enabled these people

471
00:36:44,060 --> 00:36:45,750
to exploit the desert,

472
00:36:45,750 --> 00:36:48,390
keeping their animal herds on the move

473
00:36:48,390 --> 00:36:52,514
so they don't overgraze what little vegetation there is.

474
00:36:52,514 --> 00:36:54,980
(gentle music)

475
00:36:54,980 --> 00:36:57,760
Most deserts have indigenous people

476
00:36:57,760 --> 00:36:59,960
who have adapted to the challenging terrain.

477
00:37:06,740 --> 00:37:08,440
The San people,

478
00:37:08,440 --> 00:37:10,960
once known as the Kalahari Bushmen,

479
00:37:10,960 --> 00:37:15,393
have inhabited Southern Africa for at least 20,000 years.

480
00:37:20,040 --> 00:37:22,200
From their Stone Age ancestors,

481
00:37:22,200 --> 00:37:25,833
they maintain a nomadic desert lifestyle in the Kalahari,

482
00:37:28,730 --> 00:37:31,300
using an intimate knowledge of the landscape

483
00:37:31,300 --> 00:37:34,253
and its plants and animals to find everything they need.

484
00:37:43,991 --> 00:37:46,741
(water sloshing)

485
00:37:48,040 --> 00:37:50,800
They use the poisons of plants and insects

486
00:37:50,800 --> 00:37:53,070
to make lethal spears

487
00:37:53,070 --> 00:37:57,123
and track their quarry until the poisons bring it down.

488
00:37:57,123 --> 00:37:59,873
(dramatic music)

489
00:38:06,120 --> 00:38:09,570
The cultural identity of the San faces extinction

490
00:38:09,570 --> 00:38:13,450
in the light of modernization and globalization.

491
00:38:13,450 --> 00:38:14,800
But there is another threat

492
00:38:16,330 --> 00:38:18,143
not only to their way of life,

493
00:38:19,400 --> 00:38:22,553
but to deserts and to the world.

494
00:38:22,553 --> 00:38:25,440
(traffic rumbling)

495
00:38:25,440 --> 00:38:27,910
The massive expansion of the human population

496
00:38:27,910 --> 00:38:30,200
over the last few hundred years,

497
00:38:30,200 --> 00:38:33,370
and especially its industrialization,

498
00:38:33,370 --> 00:38:35,543
has changed the planet's atmosphere.

499
00:38:42,510 --> 00:38:44,450
Carbon and other gases

500
00:38:44,450 --> 00:38:47,410
added to the air through the burning of fossil fuels

501
00:38:47,410 --> 00:38:48,623
acts as a blanket,

502
00:38:51,480 --> 00:38:52,970
trapping heat from the sun

503
00:38:54,341 --> 00:38:56,300
(gentle music)

504
00:38:56,300 --> 00:38:57,863
and making Earth warmer.

505
00:39:00,490 --> 00:39:01,743
And that's not all.

506
00:39:08,900 --> 00:39:11,420
For fuel, building materials,

507
00:39:11,420 --> 00:39:13,560
and to clear space for livestock,

508
00:39:13,560 --> 00:39:16,850
the growing human population has cut trees,

509
00:39:16,850 --> 00:39:18,827
taking away the shade they provided

510
00:39:18,827 --> 00:39:21,733
and their roots that bound the soil.

511
00:39:21,733 --> 00:39:24,566
(trees crackling)

512
00:39:34,518 --> 00:39:37,101
(birds cawing)

513
00:39:40,573 --> 00:39:43,073
(sheep bleat)

514
00:39:45,770 --> 00:39:48,113
Too much livestock is being put on the land.

515
00:39:54,820 --> 00:39:57,623
Overgrazing destroying the plant life.

516
00:39:58,780 --> 00:40:02,523
And intensive farming has reduced the fertility of soil.

517
00:40:08,950 --> 00:40:11,410
These, combined with climate change,

518
00:40:11,410 --> 00:40:15,633
can alter fertile landscapes and turn them to desert.

519
00:40:19,560 --> 00:40:22,670
It is believed the Sahara has grown by 10%

520
00:40:22,670 --> 00:40:24,533
in the past 100 years.

521
00:40:28,350 --> 00:40:31,543
And all deserts continue to grow to this day.

522
00:40:32,594 --> 00:40:35,177
(gentle music)

523
00:40:45,720 --> 00:40:47,690
4,000 years ago,

524
00:40:47,690 --> 00:40:51,443
the Sahara was a lush, green, and productive landscape.

525
00:40:56,730 --> 00:40:59,900
It only took a tiny wobble of the Earth's axes

526
00:40:59,900 --> 00:41:02,040
and a minute temperature change

527
00:41:02,040 --> 00:41:03,293
to produce desert.

528
00:41:14,600 --> 00:41:17,790
A reminder of how quickly and how drastically

529
00:41:17,790 --> 00:41:20,143
habitats across the world could change.

530
00:41:22,730 --> 00:41:24,823
And it's a self-fulfilling cycle.

531
00:41:26,200 --> 00:41:30,093
The desertification of land leads to more crop failures,

532
00:41:31,040 --> 00:41:34,403
more erosion, famine, and drought.

533
00:41:35,839 --> 00:41:38,339
(tense music)

534
00:41:44,860 --> 00:41:47,893
Millions of people are already impacted.

535
00:41:51,076 --> 00:41:53,993
(hatchet clinking)

536
00:41:57,480 --> 00:42:00,923
In fact, 1/6 of the world's population lives in desert,

537
00:42:02,510 --> 00:42:04,643
and their lives are at risk.

538
00:42:07,210 --> 00:42:09,610
Though there are many ways to fight the problem,

539
00:42:13,060 --> 00:42:16,473
using desert hardy crops that can enrich the soil.

540
00:42:17,411 --> 00:42:20,244
(uplifting music)

541
00:42:35,700 --> 00:42:38,060
Careful water management and irrigation

542
00:42:38,060 --> 00:42:39,813
to use water sustainably.

543
00:42:47,610 --> 00:42:52,610
And perhaps most of all planting trees to act as windbreaks,

544
00:42:53,030 --> 00:42:55,303
stabilizing and shading the soil.

545
00:42:59,590 --> 00:43:01,190
Reducing the ground temperature.

546
00:43:12,070 --> 00:43:15,310
Desert has great potential for wind and solar farms

547
00:43:15,310 --> 00:43:17,193
to produce renewable energy.

548
00:43:22,400 --> 00:43:25,670
In fact, it's thought covering just 1% of the Sahara

549
00:43:25,670 --> 00:43:27,050
in solar panels

550
00:43:27,050 --> 00:43:29,973
would provide enough energy for the whole world.

551
00:43:37,030 --> 00:43:40,629
♪ Wooo ♪

552
00:43:40,629 --> 00:43:42,546
♪ Wooo ♪

553
00:43:43,500 --> 00:43:45,270
And an ambitious project

554
00:43:45,270 --> 00:43:48,740
is building a wall of trees across the Southern Sahara

555
00:43:48,740 --> 00:43:52,160
that will be the largest living structure on the planet,

556
00:43:52,160 --> 00:43:54,550
8,000 kilometers long,

557
00:43:54,550 --> 00:43:57,860
which is already improving the health and livelihoods

558
00:43:57,860 --> 00:43:59,410
of the people living around it.

559
00:44:00,330 --> 00:44:03,609
♪ Ooo ♪

560
00:44:03,609 --> 00:44:05,526
♪ Wooo ♪

561
00:44:12,080 --> 00:44:14,180
Deserts don't have to be bad.

562
00:44:17,270 --> 00:44:20,550
They are beautiful and important habitats

563
00:44:20,550 --> 00:44:23,750
for unique plant and animal species.

564
00:44:23,750 --> 00:44:27,190
But they are fragile and need protecting

565
00:44:27,190 --> 00:44:29,468
to continue their magic.

566
00:44:29,468 --> 00:44:32,051
(gentle music)

567
00:44:34,050 --> 00:44:37,653
And now the desert has a final surprise in store.

568
00:44:41,000 --> 00:44:43,170
One of the defining features of deserts

569
00:44:43,170 --> 00:44:45,583
is low unpredictable rainfall.

570
00:44:46,461 --> 00:44:48,580
(rain dropping)

571
00:44:48,580 --> 00:44:49,980
Because of it,

572
00:44:49,980 --> 00:44:53,260
plants and animals can lie dormant in the ground

573
00:44:53,260 --> 00:44:55,170
and can live their lifestyles quickly

574
00:44:58,210 --> 00:45:01,200
because they know that sooner or later

575
00:45:01,200 --> 00:45:03,883
the most precious of resources will come.

576
00:45:07,891 --> 00:45:10,724
(thunder booming)

577
00:45:13,370 --> 00:45:16,120
(rain whooshing)

578
00:45:31,586 --> 00:45:33,669
It only takes a few drops

579
00:45:35,260 --> 00:45:39,000
and then seemingly in the blinking of an eye

580
00:45:39,000 --> 00:45:40,423
the desert is transformed.

581
00:45:57,150 --> 00:45:59,560
A rainbow carpet of flowers,

582
00:45:59,560 --> 00:46:03,143
a phenomenon that can spring up in deserts across the world.

583
00:46:08,410 --> 00:46:11,950
These extraordinary plants use color and fragrance

584
00:46:11,950 --> 00:46:15,363
to attract insects to pollinate them as quickly as possible.

585
00:46:40,030 --> 00:46:42,760
They will soon produce fruit and seeds

586
00:46:42,760 --> 00:46:45,080
so that as the ground dries up

587
00:46:45,080 --> 00:46:48,520
they can wither away and lie dormant in the soils

588
00:46:48,520 --> 00:46:50,143
until the rains return.

589
00:46:54,810 --> 00:46:56,610
During their glorious showdown,

590
00:46:56,610 --> 00:46:58,963
the animals of the desert get a rare respite.

591
00:47:10,800 --> 00:47:12,423
A brief time of plenty.

592
00:47:18,330 --> 00:47:21,153
They can enjoy rare generosity from the desert.

593
00:47:25,870 --> 00:47:27,833
And raise their young on the bounty.

594
00:47:34,950 --> 00:47:38,230
Some, like the elegant demoiselle cranes,

595
00:47:38,230 --> 00:47:41,193
travel to be here and rear chicks while the going's good.

596
00:48:00,620 --> 00:48:03,040
And for the year-round residents,

597
00:48:03,040 --> 00:48:05,193
there are insects in abundance.

598
00:48:09,220 --> 00:48:11,433
And the hedgehog can feast.

599
00:48:12,464 --> 00:48:15,881
(gentle music continues)

600
00:48:54,870 --> 00:48:56,253
Which is just as well.

601
00:49:00,150 --> 00:49:03,733
In her den, this female has become a mother.

602
00:49:12,230 --> 00:49:14,700
The rains have brought a much needed boost

603
00:49:14,700 --> 00:49:16,750
that will help her raise her little ones,

604
00:49:22,330 --> 00:49:27,330
preparing them as the next generation of desert survivors.

605
00:49:30,600 --> 00:49:33,183
(gentle music)

606
00:49:54,062 --> 00:49:56,812
{\an8}(wind whooshing)