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Documentary, The Future Is Wild -3 The Vanished Sea- 2002
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00:00Imagine a world millions of years in the future.
00:11A world where evolution has written a new chapter in the story of life.
00:24The world is inhabited by very strange creatures,
00:28like nothing the Earth has ever seen.
00:58Five million years in the future, and the planet is in the grip of another ice age.
01:05Yet this isn't ice or snow. It's salt, covering a hot, parched desert.
01:12But there is life here. Cryptiles, half-metre-long lizards that sprint over the burning salt.
01:18These harsh salt flats are two thousand metres below sea level.
01:21They're all that's left and the world is an absolute
01:37And they're all that's left of the desert.
01:40These harsh salt flats are 2,000 metres below sea level.
01:46They're all that's left of the sparkling, clear blue waters of the Mediterranean.
01:55But how can a whole sea just disappear?
01:59What happened to turn the holiday paradise of the Mediterranean into a salt desert?
02:04An Ice Age climate is very dry, which makes water evaporate and sea levels fall.
02:14But it takes more than a change in climate to make the Mediterranean dry out.
02:21In five million years' time, the geography of the Earth will have changed,
02:27when Africa will have pushed up against Europe and closed the Straits of Gibraltar.
02:32As the continents collide, the Mediterranean is cut off from the Atlantic,
02:38and it becomes a closed, landlocked sea.
02:43The water evaporated in the dry climate,
02:47and with no water flowing in from the Atlantic to replace it,
02:50the Mediterranean simply vanished, leaving just a few deep basins.
02:54The Mediterranean will dry out until it becomes one vast salt pan.
03:02There will be small lakes of hypersaline water left behind,
03:09the only water in the Mediterranean.
03:11But the old holiday islands of Cyprus and Malta and Crete
03:15will stand up as small mountains in the middle of this sea of salt.
03:19No shelter and no water, just the relentless sun.
03:27But if anything can survive out here, lizards can.
03:32These cryptiles, like many lizards, are tough and drought-resistant,
03:38so they're already suited to life on the salt flats.
03:40Well, in five million years, the Mediterranean will be a very different environment than it is today.
03:46And very few animals will have actually adapted purely for that new environment.
03:50The cryptile is a great example of one animal that's testing the water.
03:54It's part of the way there, but not all the way there yet.
03:57Lizards, in general, are good at surviving in hot, dry places.
04:02Today, the Lake-Air dragon lives on the vast salt flats of Australia's Lake-Air,
04:10a dry salt pan covering 10,000 square kilometres.
04:17Lake-Air dragons eat ants.
04:20Insects are the only other creatures that can survive in a salt desert like this.
04:25The lizards stand on their heels, keeping their toes off the hot surface.
04:40At over two million square kilometres, the Mediterranean salt flats are some 200 times as big as Lake-Air.
04:47But cryptiles don't just live here. They also carry out their courtship on the old Mediterranean seabed.
04:56The males compete to show off the biggest and brightest crest.
05:05And the female invites the best-looking male to follow her in a courtship dash over the salt.
05:10If he keeps up with her, she'll let him mate.
05:17But for the female, her problems are only just beginning.
05:23Now, one of the biggest problems about living in this environment,
05:26this very, very salty environment, is that if you're a lizard, there's nowhere to lay your eggs.
05:31If you dig a hole in the salt and lay them, they will just shrivel up.
05:33All the water will be taken out of them, and they will be dead very quickly.
05:36So the females have to move away to find places where the soil, in order to deposit their eggs.
05:43This is a time when they're in the greatest danger,
05:45because they're very well adapted for living on the open salt plain.
05:48The colour, the shape, everything is for salt plain life.
05:51When they go onto the soil, this is when they stand out like a sore thumb.
05:55And this is when they're open to be eaten by predators.
05:59So a female has to leave the safety of the salt flats to lay her eggs.
06:03She heads for the old Mediterranean islands that rise out of the salt.
06:11These are mountains of bare rock worn into a broken, cracked pavement known as Karst.
06:20Running across the Karst, there are deep cracks and crevices called grikes.
06:25Although many of the cracks are only a few centimetres wide, some of them go down two or three metres.
06:43Ideal places to lay eggs.
06:45The narrowest cracks are far too tight for a predator.
06:52And there is a predator here that uses the bigger grikes as secret highways across the Karst.
07:00The cryptiles' eggs are safe in the bottom of a narrow grike.
07:04It's not the eggs that are in danger, but the cryptile herself.
07:17From a griken.
07:18The cryptile has the advantage of speed, so the griken will go hungry.
07:33Grykens live only on these isolated bare mountains and rocky plateaus.
07:37They're about 20 centimetres tall at the shoulder, with a sinewy body small enough to wriggle through crevices in the rock.
07:54But its ancestor had a very different lifestyle, living in the tops of trees.
07:59Today, Europe's natural vegetation is forest, and it's said if humans hadn't cleared the trees, a squirrel could run from Spain to Greece without ever touching the ground.
08:16But it would be followed all the way by a pine marten, the ancestor of the griken.
08:21Pine marten's are fast, agile predators that spend most of their time in the branches.
08:38Their bodies are flexible and supple, and they have a superb sense of balance.
08:42But five million years in the future, in the Ice Age climate, trees will be a rare sight in Europe.
09:07Grykens evolved in only five million years.
09:11It's not that different from the pine marten it evolved from, but the climate has dried, the trees have gone.
09:17Pine marten's had long back legs to help them leap through the trees, and tails they'd used to help them maintain balance.
09:25But Grykens are different. They have longer legs, so they can run along the grikes.
09:31And as Grykens no longer climb trees, they don't need their ancestors' long tail for balance.
09:39Their bodies have elongated, so they can squeeze through the narrow crevices in the rocks.
09:46Grykens also have dagger-like teeth.
09:51They need them to bring down their favourite prey.
09:56Small, delicate-looking pigs. Scrofers.
10:02Scrofers can't run as fast as cryptiles, so they're easier for the Grykens to catch.
10:13Especially the tender, young pigs.
10:24But the big, adult males are aggressive.
10:39Too aggressive for the Grykens.
10:43Too aggressive for the Grykens.
10:46We're five million years in the future, and Scrofers are descendants of the wild boar that used to roam over much of Europe and Asia.
11:02Today, wild boars live in rich forests that still cover much of Europe, and they're found in many of the countries surrounding today's Mediterranean.
11:12The adults are big, heavy-set animals that can weigh more than 100 kilograms.
11:23They have sturdy, strong legs for moving across the soft forest floor.
11:29And they root around in the deep woodland soil for insects, worms, tubers, fungi.
11:39Their sensitive, flexible snouts unearth anything that's edible.
11:43They live in tight-knit family groups of a few adult females with their young, and a few juveniles.
11:58Despite being at home in the forest, wild boar are just the kind of animals that would survive when their forest home disappears.
12:05In the future, they've had to adapt to living on bare limestone, and they had to do it relatively quickly as the climate changed.
12:19The landscape that Scrofa lives in has been created very rapidly, perhaps in only a few tens of thousands of years.
12:25But the Scrofa has managed to adapt to live in this landscape because pigs are highly adaptable.
12:30They're generalists, they can eat a wide variety of food types, they can live in a lot of habitats.
12:35And so the Scrofa is one of the species that's managed to adapt to this new landscape.
12:40Walking over rugged limestone is very different from trundling through a forest.
12:46Scrofa legs have become thinner, and the bones elongated.
12:50They walk on the tips of their toes, giving them a strange, stiff-legged gait.
12:58But this is the most efficient way to move over hard surfaces like the cast.
13:05The whole animal is only half the height of its bulky, wild boar ancestor.
13:11The Scrofa is a small pig because it's living in a habitat where there's not a great amount of food.
13:15It's got sharp pointed hoofs to help it move across the rocky surface.
13:20Long thin legs because it needs to move quite long distances, but also it's got to leap across the cracks in the rocks.
13:30A pig that walks like a ballerina may seem unlikely.
13:34But there is a creature around today that has a similar design.
13:42The Clipspringer.
13:44Clipspringer are antelopes that live on rocky outcrops in Africa.
13:49And they've also evolved the same tip-toe, stiff-legged gait to scramble over bare rock.
13:53The Clipspringer and Scrofa are totally unrelated, but have evolved the same solution to the same problem.
14:10And so, they look very similar.
14:14In the future, Scrofers have solved the problem of moving over rock, but there's another problem to solve.
14:20There's not a great amount of food in this landscape, and the Scrofa has a very long pointed snout,
14:27so it can actually poke down into the grikes in the rocks to find the bits of plant that are growing there.
14:32It's particularly after the roots, the tubers, the bulbs, anything that's edible.
14:36And that includes cryptile eggs, if they're not laid deep enough.
14:43But sticking a long snout down a grike can be dangerous.
14:47Although a griken won't attack an adult Scrofa, it'll sneak up on any youngsters that wander away from the family.
14:59And it uses the cover of the grikes to creep closer and closer.
15:17An isolated young Scrofa has no defence out in the open.
15:26The Scrofa family scatters, and the griken finally makes a kill.
15:31The Scrofa family scatters, and the griken finally makes a kill.
15:46This is a huge, featureless landscape, and it's very easy to get lost.
15:51And surrounding the rocky islands, the harsh, endless salt flats.
16:00The worst place a young Scrofa could find itself.
16:03But in all the confusion after the kill, one of the baby Scrofers has lost its way.
16:09It may be an ice age, but out here, in the blinding glare of the salt, 2,000 metres below sea level, it gets hot.
16:21Six degrees hotter than the Mediterranean of today.
16:25A young Scrofa won't find anything to eat out here, and even more critically, there's nothing to drink.
16:31Dehydration is a serious danger for a small pig in this heat.
16:39There is water here, but it's lethal, much too salty to drink.
16:52As the sun evaporates the sea, it leaves behind lakes that are ten times more salty than seawater.
16:59So finding one of these brine lakes is worse than useless for the poor Scrofa.
17:20These hyposaline, very, very salty pools may seem the kind of habitat in which nothing can thrive.
17:27But there are animals that positively enjoy such conditions.
17:32Like the brine flies that you can find today in Lake Mono, these sorts of creatures will live there in their millions.
17:40Animals that have learned to cope with very harsh conditions, sometimes profit by it.
17:45In the future, just as today, nothing much can live in these salty lagoons other than brine flies.
17:55So they breed here in their billions.
18:05Their only food are algae that can tolerate the salt and live in the water.
18:10So the flies have to crawl underwater to feed, surrounded by an aqualung, a silvery bubble of air.
18:17This works so well that the air over the Mediterranean brine lakes is black with flies.
18:34The flies themselves don't live more than a few days, but they breed so quickly they dominate the landscape.
18:50But Scrofers can't eat brine flies.
18:56Evening brings some relief from the heat, but none from hunger or thirst.
19:21It's not anger or thirst.
19:36Next morning, the fierce heat will return with the sun.
19:39It's unlikely that any animal not adapted to these harsh conditions could survive more than a day here in this endless desert.
19:56It seems like there's nothing here, just flies, salt and cryptiles.
20:09So if the Scrofa has no chance of survival, how do the cryptiles do it?
20:34There's plenty of food around the lake.
20:41The problem is to catch it.
20:44A cryptile trawls through the huge swarms of flies, using its large neck frill as a fishing net.
20:57And with its long tongue, it licks the trapped flies off the net as it runs.
21:04The most amazing thing about the cryptile is its frill.
21:17It's got this enormous, great big frill, which has evolved from the skin around its neck to enormous proportions.
21:24And it's got cartilage inside, so it can actually erect the frill as it looks about as big as a saucepan when it faces you.
21:30This is the adaptation it's got ready for feeding, because this frill is like a lattice structure.
21:36It's full of holes between the schedules, and there's a waxy secretion.
21:41This has a sticky waxy secretion that covers the frill, so when it runs forward through all these flies and they're scattering all directions,
21:47many of them get caught on this sticky frill.
21:50It's a bit like a mobile fly paper, if you like.
21:52And then it can turn around with its long tongue and lick off all those flies which is caught on its frill.
21:58Well, the frill itself has probably evolved, as I say, from loose skin from around its neck.
22:05Things like the frill is living today in Australia has a big frill, so you can see how that would evolve from that.
22:10Many other lizards also have a mouth fringe as well, where they can expand the skin on the side of the mouth in order to frighten off predators.
22:17A big red flash like this would frighten off a snake or another bigger lizard.
22:21So you can see this sort of frill would have actually evolved over the course of time from extra loose skin around the neck.
22:28The cryptile is unique. It doesn't drink. It gets all the moisture it needs from the insects, the flies that it feeds on.
22:39Flies are full of moisture, and it eats dozens and dozens every day, and that provides it with enough water for it to survive.
22:45So it never, ever drinks water. It would be fatal if it actually drank some of this water. It's too salty.
22:50So the cryptile survives by eating and drinking flies.
23:01But a few lizards make no impact at all on these vast numbers of brine flies.
23:15And the lizards can live here, because they're very specialised.
23:19For anything else, life on the huge salt flats is impossible.
23:29The baby scrofa has succumbed to the heat.
23:32Life on the barren limestone cast is almost as hard.
23:39But for the scrofers and grykens, it's their only home.
23:45The ice age swept over this world at breathtaking speed, less than 10,000 years.
23:51So only those creatures that were adaptable, like lizards, pigs, pine martens, could survive.
24:03The ice age, five million years in the future, didn't just bring frozen wastes.
24:21It dried out the Mediterranean Sea to create a vast, unforgiving desert of salt.
24:28The ice age is the
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