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01:02In the back of beyond lies a shimmering wilderness, where even the stones seem to burn.
01:16It's been called the Never-Never, the dead heart of Australia.
01:26Three-quarters of the continent is arid now, but once this vast interior was a place of
01:31plentiful rain, with rivers flowing into great lakes.
01:44Even today, huge rains occasionally transform the arid lands into a semblance of that wetter
01:59past.
02:02In these deep valleys, runoff from the infrequent rains filters through the rock long after
02:08the surrounding country has dried out again, and the water preserves stands of ancient palms.
02:23Permanent pools team with fish.
02:25They are now able to cope with wild swings in water temperature and salinity, and they
02:31breathe into vast shoals when the heavy rains flush them out into the desert rivers.
02:44That happens perhaps only a few times each century now.
02:48Most of the time, the rivers are dry.
02:50And yet, they're far from dead, for deep within their sandy beds, there's moisture left behind
02:57by the last rains.
03:00It's these hidden waters which support a rich mosaic of life through even the driest times.
03:15Millions of years of erosion carved deep and wide through the shields of rock.
03:24Pillars of harder stone remained, while the rest of the plateau wore away to form the deserts
03:31of central Australia.
03:37Ancient floods scattered the eroded rock into plains of stone, the Gibber Deserts.
03:43Their bright sheen, a film of iron oxide left by evaporated moisture.
03:59It seems that nothing could grow here amid this wilderness of rock.
04:04Yet, amazingly, there's life.
04:10The shingle-backed lizard seems a pattern of stone until it moves.
04:16There aren't many places to hide, and camouflage is a good defense.
04:22Reptiles manage well here, for they can do without regular food or water.
04:33While there isn't enough to support many mammals or birds, the Gibber bird does thrive here.
04:43There are sufficient insects to supply all its needs, including the little moisture it requires.
04:54It escapes the worst of the blistering heat in what shade there is, holding the wings out to keep air
05:01circulating close to its body.
05:09The fierce winds that came with the last great drying of Australia, 20,000 years ago, sifted the sand from
05:16the Gibber and swept it into vast dunes.
05:38Row upon row of dunes arc halfway around the continent, some running without a break for 300 kilometers.
05:58The sand seems a meager basis for life, yet life there is.
06:03Its presence is written in the sand.
06:10A moving ripple announces a most intriguing and secretive creature, the marsupial mole.
06:16The mull spends much of its life swimming through sand.
06:21Its sturdy little claws are shaped like shovels.
06:26Eyes would be useless beneath the surface, and they've all but disappeared.
06:30Instead, it relies on touch and smell to find its subterranean meals of grubs.
06:46But not all that ripples is a mole.
06:51Some lizards have also become sand swimmers.
06:57Several skinks have gradually lost their legs, the easier to slip through the shifting granules and sneak up on insects.
07:06But this grasshopper's come up with a defence.
07:09Already patterned like sand, it completes the vanishing act with a flurry of shovelling legs.
07:25In the swales between the dunes, a crust of clay and sand has formed.
07:30And in the years between rains, it lies sun-baked and cracked.
07:35These miniature canyons are home to Australia's tiniest marsupials, the Plannigales.
07:43They weigh as little as six grams, and their heads are flattened to squeeze through the narrow spaces in search
07:50of insects.
08:06But small mammals also make attractive prey for the desert snakes.
08:11But small mammals also make attractive prey for the desert snakes.
08:38Reptiles are the major predators in these parts, and the most formidable of them all is the Perenti, a giant
08:46goanna two metres long.
08:53Much of its prey hides from the sun, but the forked tongue picks up even the faintest traces of scent.
09:17The snake is extremely venomous. Bashing it breaks the back and leaves it helpless.
09:42A meal this size can last a month or more.
09:46Storing food in layers of fat enables them to thrive in this unpredictable region.
10:04The desert dunes overlie and re-channel ancient river courses that once drained into a huge inland lake.
10:12What shimmers now is salt, left by thousands of years of evaporation.
10:29Today, lake air is the driest place on the continent, and among the hottest.
10:35It lies fifteen metres below sea level, and temperatures can soar to a scorching sixty degrees.
10:45Yet even at this harsh extreme, some animals flourish.
10:52Lake air dragons survey their salty domain.
10:56Their eyelids shape like sun visors against the blinding glare.
11:03They feed on ants, which harvest insects blown onto the salt.
11:17The ant mounds also serve as lookouts to spot potential mates or rivals.
11:31To avoid actual battle, the dragons have evolved a most eloquent body language.
11:38Head bobs, push-ups and arm waves sort out the hierarchy,
11:44and signal readiness for mating or reluctance.
12:01This male's proved his dominance.
12:04Now he can feed undisturbed, walking on the heels so as to keep toes from getting burnt.
12:17The dragons manage to thrive in conditions that would defeat most other creatures.
12:26And most of the time, their domain remains undisturbed.
12:30But a few times each century, lake air becomes a sea again.
12:37Most of central Australia drains into lake air.
12:42Usually runoff from light rains evaporates long before it reaches the lake.
12:47But occasionally, a tropical cyclone dumps huge rains across the remote channel country.
13:15It's these unpredictable heavy drenchings that are the crucial events in the life of the arid country.
13:28Water falls in such abundance that it soaks deep into the parched earth
13:33and replenishes the hidden stores which keep the plants and animals going when the dry times return.
13:45The downpour is a welcome chance for the desert animals to drink their fill.
13:50And for these galas to wash the dust out of their feathers.
14:15In this region of little and erratic rain, the survivors are those who, like this spiny-tailed gecko,
14:21make the most of every opportunity.
14:24Normally it emerges only at night.
14:33A praying mantis sips the droplets that gather on its arms.
14:51The thorny devil drinks in a most ingenious fashion.
14:56The sculpting of the scales creates fine channels which draw the water to the corners of the mouth.
15:11The rain is heavy enough to sink deep into the sand.
15:16A metre or so down, it wakens a most surprising animal to find in the desert, a frog.
15:24Yet frogs live here in abundance, for they cope with drought in a remarkable way.
15:30They escape underground for years, cocooned in a second skin to keep their body moist.
15:43That shroud provides the first meal when the kiss of water ends asleep that may have lasted five years.
16:02Then comes a brief but glorious spell of freedom.
16:06Feeding and breeding until the returning dry sends the frogs back into their time capsule.
16:16The desert plants have their own ways of making the most of the rain.
16:21Many mulgars are shaped like inverted umbrellas.
16:27The rain is funneled down the leaves and branches, then cascades down the trunk.
16:38The water soaks in around the base of the tree and recharges the underground stores.
16:51The cracked clay between the sand dunes soon become saturated and forces the planigale to seek higher ground.
17:10There's been so much rain here in the channel country,
17:13but the runoff races hundreds of kilometres down the dry creek beds towards the arid heart.
17:36The waters replenish the subterranean reservoirs, carrying the benefits of the rains a long way from where they actually fell.
17:48Once again, masses of water are surging towards lake air.
18:03So suddenly did the rivers rise that they caught this gecko unawares.
18:15It's a marvellous transformation from bone-dry sand to water churning with fish.
18:27They bred from stocks in isolated water holes flushed out by the rains.
18:44These cormorants are among the legions of water birds which follow the newly flowing rivers into the flooding desert.
19:11The rivers carry so much water they flood out across plains that are among the flattest on earth.
19:27The warmth of the sun and the wealth of fresh nutrients brings everything to life.
19:38Dragonflies and insects of all kinds are in a frenzy to reproduce, to make the most of the good times
19:43while they last.
19:51The touch of water stirs dormant eggs into life and the clay pans soon teem with shield shrimps.
20:01This is a most fleeting existence, for this shallow water won't last long.
20:06Two weeks after hatching they mate and lay eggs that may lie dormant for 25 years.
20:30The budgerigars know the rain will produce a flush of food and they gather in trees lining the flooded rivers
20:37to form pairs and start families.
20:46These nomadic little birds are well tuned to the shifting fortunes of the interior.
20:51They mature quickly and the males produce sperm when they're only a few months old.
21:18The flooded rivers become flyways for ever more invasions from the continent's wetter margins.
21:23Long lines of water birds follow the shining trails deep into the heart.
21:40The wave of life reaches its crest in Lake Eyre, transformed again into a mighty inland sea.
22:08Water now stands metres deep where the dragons performed their courtly dance.
22:14They've fled to the shores and the lake belongs to the birds.
22:21Close to shore, redneck avocets sweep through the mud for brine shrimps.
22:31Further out, pelicans flock together to round up the teeming fish.
22:39The floods have turned the salty desert into a vast bowl of rich soup that supports breeding colonies of enormous
22:46size.
22:48Just in this one place alone, 15,000 pelicans gather to breed.
22:54The wind fell into the Arctic sea water and the Sea Onyxan.
22:57The coast of the Sea Onyxan.
23:10The coast in the island of Sweden, 15,000 pelicans skate.
23:13The fishnets, 15,000 pelicans get to the sea onyxan, 17...
23:13The sea onyxan.
23:16The sea onyxan.
23:33In their regular habitats, pelicans and gulls breed only once a year, but here they'll
23:38keep producing clutches till the food runs out.
23:52There are broods at all stages of growth, from naked hatchlings to young pelicans ready
23:57to take wing.
23:58With no predators to worry them, the gravest threat comes from the relentless heat.
24:09Inevitably some will perish, but for a time Lake Eyre offers what counts most, an abundance
24:16of food.
24:25Elsewhere, the rains have painted the desert with glorious colour.
24:49These are the ephemeral short-lived desert plants.
24:52They sit out the dry years in time capsules, dormant seeds which only rain can unlock.
25:06Like this Sturt's desert pea, their flowering will be brief, and in their urgent need to
25:12attract pollinators, they provide copious nectar.
25:23The plants set great quantities of seed, so they'll be enough to last till the next rains.
25:41The flowers vanish as swiftly as they bloomed.
25:44Their abundant seeds will feed many creatures for a long time to come.
25:59Most of the desert animals come out only in the cool of the night.
26:03Avoiding the daytime heat is one way these hopping mice have made themselves at home in
26:09the sandy desert.
26:11They also get their moisture from seeds, and they've evolved a speedy hop to escape their
26:17enemies.
26:22The hopping mice almost vanish in the dry years, but plentiful food stimulates them to
26:28multiply rapidly.
26:36They're very social creatures.
26:38As many as ten live together, and their communal burrows are marvels of design.
26:44As well as a main entrance, there are several escape holes, and the main living area is a
26:50metre or so down, to avoid the extremes of hot and cold.
27:13Young are born about four weeks after mating, and part of the burrow becomes a nursery.
27:19They're usually four in a litter, and mothers suckling one brood may already be pregnant
27:25with another, to reproduce even more quickly in this time of plenty.
27:43Long after the rains, the water that's soaked into the sands, sustains the arid region's
27:48most characteristic plant.
27:51Spinifex is a uniquely Australian grass, and covers a third of the interior.
28:01This grasshopper mimics the foliage, one of many creatures thriving within the spiky ramparts.
28:12Deep tap roots reach the moisture metres down, and surface roots seek what few nutrients
28:19the soil has to offer.
28:26As a result, spinifex grows outwards in ever-widening rings.
28:39In some places, the tussocks are linked by these intriguing, tunnel-like structures.
28:50The runways are built by ants, using grains of sand, glued together with drops of spinifex resin.
29:16The covered trails shield the ants from sun and predators on the way to their food supply in the spinifex.
29:25The ants protect the source of that food with more sand and resin shelters.
29:30Within them, minute sap-sucking insects are at work.
29:44And this is the purpose of the ants striving.
29:47Sugary drops that are the waste product of the insects feeding on the spinifex sap.
29:54Together, these tiny droplets provide all the energy needed to drive an entire ant colony.
30:06Using some of that energy to build runways is a wise precaution.
30:10Ants without that protection may fall victim to the thorny devil.
30:28On higher ground, there's sufficient vegetation to support one of Australia's creative artists, the Western Bowerbird.
30:41It shapes stalks of grass into an elegant bower and decorates them with desert fruits and berries.
31:00The calls lure a female to the bower.
31:08Its sole purpose is to impress her.
31:11And to serve as the arena for the male seductive display of song and dance.
31:45The sounds of the translating in front of the animal to the male seductive display of one of the ages.
31:46The human race can be more severe and just the raw tools that make itrire these animals.
31:49When evening comes and the sands cool, the pace of life among the spinifex quickens.
31:56Scorpions and other creatures that have spent the day shielded from the sun come out to hunt.
32:04There's much food about, but also danger from other hunters.
32:10The striped-faced dunnart, a ferocious marsupial carnivore, tackles almost anything, even a venomous centipede.
32:38Dunnarts belong to an ancient marsupial group. Although females do have a pouch, it's too small to hold six growing
32:46young for long, and some occasionally lose their grip.
33:13Hanging on to mother is vitally important.
33:15Dunnarts are always moving their home range to keep up with the shifting supplies of insect food.
33:25There's no advantage for dunnarts in having a regular nest or burrow.
33:29But for this little creature, a permanent home makes much sense.
33:35The pebble-mound mouse has reliable food of seeds and tubers nearby.
33:40And making a shelter from heat and enemies is well worth even this prodigious labour.
33:46Some of the stones are bigger than itself.
33:59The stones are piled in a circle around the entrance.
34:03On dewy nights, they collect moisture to drink.
34:18The arid landscapes are a patchwork made by millions of years of shifting and leaching soils, from sands to stony
34:26ground.
34:28Some retain more of the recent rains, some less.
34:32The variations shape an astonishing diversity of life.
34:41The mulga is the characteristic desert tree.
34:45In favoured places, it produces a nectar that's promoted an extraordinary animal response.
34:51The nectar flows from small leaf glands, and the ants it attracts keep leaf eaters away.
35:19Many ants come to feed on this mulga honey.
35:22But because the flow varies considerably, certain species have evolved an ingenious way of storing it.
35:31In these unusual colonies, a special cast never leaves the nest, but serves as living stores.
35:38Their bellies hugely distended into translucent honey pots.
36:02When the nectar flow dries up, the colony taps into the storage ants.
36:07Stroking stimulates them to release the sweet liquid, a tiny drop at a time.
36:15Nursing ants only digest a little themselves, and feed the rest to the larvae in their care.
36:21In the near future, it's a natural plant.
36:34These busy insects are the most numerous inhabitants of the arid lands.
36:39About half of Australia's 5,000 species of ants live here.
36:46Through some remarkable interactions with the plant world, ants play a major part in shaping the environment,
36:53carrying vast amounts of plant material, and turning over the desert's meagre stores of nutrients.
37:02But ants also exploit seeds, and so short-lived plants produce huge quantities.
37:08Some at least will escape the columns of foragers.
37:17Some of the permanent plants actually turn the ants' appetite to their advantage.
37:23Desert trees won't thrive too close together in these poor soils, so the seeds need to be dispersed.
37:31Birds sometimes help by distributing seeds in their droppings, but not these galahs.
37:37What they eat, they digest.
37:43The remainder drops close to the trees.
37:47Were they to sprout here, they would compete with their parent for nutrients and moisture.
37:52So ants have been enticed to carry them away.
38:00The seeds themselves are ant-proof, but they're packaged with an attractive food.
38:05Oil-rich bodies called aliosomes.
38:22In the underground chambers, nurses and other workers labour together to remove the aliosomes,
38:29and distribute the food to the rest of the colony.
38:38The seeds are just waste, and dumped on a rubbish heap in a distant gallery,
38:44there to await the germinating touch of the next rains.
38:55Some trees use the wind to get their seeds away.
39:00Dispersing seeds gives the saplings more space to grow extensive roots,
39:04and make the most of the little moisture in these soils.
39:14While the desert rivers have long stopped flowing,
39:17masses of water run deep within the sandy beds,
39:20enough to sustain the mighty river red gums.
39:32All that's left on the surface is a chain of pools,
39:35and most of those will vanish soon.
39:38But the moisture flowing in the hidden rivers
39:40supports generous stands of the river reds through even the driest times.
39:54Clouds of corellas roost in the gums on their travels around the interior,
39:58following the moveable feast of seeds and fruits.
40:22It's not hard to think of these antics as pure play,
40:26a means of whiling away the long hours between feeds.
40:53Come breeding time in late winter, the flocks break up,
40:57and the corella couple start looking for nesting hollows.
41:09In this season of plenty, every suitable hollow is soon occupied.
41:16This pink cockatoo already has chicks in the nest.
41:20It approaches cautiously, so as not to alert predators.
41:38The parents take it in turn to feed their youngsters.
41:42There's still an abundance of seeds and fruits to collect,
41:45and the birds make many trips a day to pump the mash
41:49into the ever-beckoning young beaks.
42:06The chicks are now a fortnight old.
42:09In another month, they'll be strong enough to follow their parents and fly.
42:17Cockatoos are hardy and resilient birds,
42:20well-designed to cope with the rigours of arid life.
42:23But they can't do without water.
42:25slowly will work in place.
42:33There!
42:39Hell's likely persones,
42:40They're Europol kimê·¸ë ‡s and stones,
42:55This steeper pool will remain filled well into the dry times,
42:59and it becomes the focus for much of the animal life of the surrounding plains.
43:06Red kangaroos can go without water for months while there's fresh growth,
43:10but when that's gone, they need to come in for a drink once or twice a week.
43:19Those other large plains dwellers, the emus,
43:22need water nearly every day once it gets really hot.
43:35With so many kangaroos crowding together,
43:38tussles often break out among rival bucks.
43:54When night falls, the cockatoos find resting places in the trees nearby,
43:59and the big reds start moving back to their home ranges to feed in the cool of the night.
44:10Too many kangaroos.
44:14Good.
44:32Yes.
44:44Grasses that grew tall in the wake of the rains have dried out
44:47and the green pick that the kangaroos need for moisture
44:50is harder to find
45:02The rising sun swiftly sends the temperatures soaring to 40 degrees
45:06and the kangaroos move to what meagre shade they can find
45:23Such large and warm-blooded animals should have real problems in this kind of heat
45:28yet the kangaroos cope remarkably well
45:33One way they keep cool is to lick parts of their body
45:36where the blood vessels run close to the surface
45:57While the reds shelter in the shade the emus carry their own heat shields
46:02A double layer of feathers insulates them very efficiently
46:06and they can keep foraging through the heat of the day
46:22As the dry tightens its grip, food and water start to run out
46:26and the big reds have to move on or perish
46:36The awkward shuffle of their feeding gate shifts into an effortless fluid bounce
46:42The energy of each hop is stored in the hind leg tendons
46:46like a spring to provide the propulsive force for the next
47:06For those that leave too late, the end is inevitable
47:13The diminishing resources simply won't sustain the numbers that flourished in the time of plenty
47:26It won't be long before the mud in this pool is baked hard again
47:30Too hard for the animals to penetrate to the moisture below
47:40Soon the females will stop producing milk and the joeys will die
47:44But if the does manage to survive till conditions improve
47:48they'll quickly breed again
47:55For a time, the great die-off provides a feast for the hunters and scavengers of the arid country
48:19Soaring on wings spanning two and a half meters, the mighty wedge-tailed eagle, Australia's largest bird of prey, scans
48:27the drying country for dead and dying animals
49:00I'm not going to lose.
49:00Eagles feed on carrion as well as live prey.
49:05But even carrion is becoming scarce
49:07and hunger drives the birds into fierce competition
49:10for the little food that remains.
49:49Two years after it began to fill,
49:52Lake Eyre, the great sea at the heart of the continent,
49:55has dried to salt again.
50:01Rows of dead fish mark the receding shores.
50:17The legions of birds that flourished here have vanished.
50:21The last of their broods abandoned.
50:26These cormorant chicks had the misfortune
50:29to be at the end of the line when the food ran out.
50:32Nothing can save them or the pelican broods.
50:54But though the images speak of death,
50:57they belie the fact that this so-called dead heart
51:00can also be a place of extraordinary fertility.
51:05Even while the flood of life that came with the rains ebbs away,
51:10the underlying pulse continues to beat strongly
51:13and the permanent inhabitants reappear.
51:18The lake-air dragons are coming back
51:20now that the country is returning to its normal state of drought.
51:28Lack of food left the last of the pelican flights
51:31without the strength to make their escape.
51:39The winds suck away the last traces of moisture
51:42and leave the plains bone dry.
51:48But deep beneath the waves of sand and dust,
51:51the hidden aquifers still run.
51:54The lifeblood that keeps the arid heart beating.
52:14Even on the salt beds of lake air, seemingly so dead,
52:18life continues to proclaim its vigorous existence.
52:29The lake-air dragons have reclaimed their dominion.
52:35The males reassert their dominance
52:37with inflated impressions of their size.
52:48Soon the hierarchy will be sorted out.
52:50Each dragon will have its place in which to feed and breed,
52:54to live and die.
53:07The challenge in the arid centre
53:09is not so much lack of rain as its unpredictability.
53:15Over millions of years,
53:16plants and animals came to meet that challenge
53:19in remarkable ways.
53:22More than 50,000 years ago,
53:24man set foot on the continent for the first time.
53:27And his response to its challenge changed,
53:30dramatically and forever,
53:32the nature of Australia.
53:36river earth and the List of May,
53:42A few months later,
53:43a young man.
53:43Oh,
53:43you know,
54:04the Lord's mess.
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