Documentary, The Future Is Wild -6- Waterland- 2002
#PermianTriassic #AncientEarth #Cretaceous #Prehistoric #Evolutionary
#PermianTriassic #AncientEarth #Cretaceous #Prehistoric #Evolutionary
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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.
00:58This is the world one hundred million years in the future.
01:05The climate is very warm and very humid, all the time.
01:11Sea levels are more than 150 metres higher than today,
01:14creating vast, shallow swamps,
01:17where mysterious creatures lurk in the dark water.
01:20warm and very humid, all the time.
01:32Sea levels are more than 150 metres higher than today, creating vast, shallow swamps
01:39where mysterious creatures lurk in the dark water.
01:46Not only is life very different now, but the planet itself has changed.
01:54The Earth's crust is broken into huge plates like pieces of a jigsaw that jostle and slide
02:00over the face of the globe at a few centimetres a year.
02:04In a hundred million years' time, the continents will be in completely different positions.
02:10But this movement is not the only reason the Earth looks so strange.
02:15Over millions of years, carbon dioxide from volcanoes has created a massive greenhouse
02:21effect, slowly warming up the planet, melting the ice caps and causing the sea level to
02:27creep higher and higher at about a millimetre a year.
02:34In one hundred million years' time, the sea will have flooded much of the dry land.
02:42So a combination of moving land masses and a rise in sea level means the globe has changed
02:48beyond recognition.
02:51And much of what looks like dry land on the globe is actually swamp.
03:04This swamp stretches for over 2,000 kilometres.
03:10So at this hundred million year and the future time frame, one of the environments which we're
03:14looking at is a huge near-coastal swamp.
03:18It's partially brackish with the influence of the ocean.
03:20It's got a huge amount of fresh water flowing down into it, reminiscent perhaps of some of
03:25the great coal swamps of 300 million years ago.
03:30Rich in life, teeming in a whole bunch of new adaptations.
03:34Very high moisture, high warmth, a steaming tropical jungle magnified.
03:40It's just the sort of place where evolution can go wild.
04:04This mighty beast is a toraton, and this one is about the size of an elephant.
04:26It's descended from a very unexpected ancestor.
04:29Well, the toraton that roams the earth in a hundred million years' time has evolved from
04:34today's tortoises, and you can still see the similarities.
04:37It's got a shell, albeit a much reduced shell, and a long wrinkly neck, just a folded skin,
04:43and a head that's covered in scales.
04:46But there are big differences.
04:47It is big, this animal, and its legs have moved from a sideways position like this in the
04:51tortoise, to, underneath the actual animal, to support it like four great big pillars as
04:57it walks along, just like an elephant's legs.
05:02Any animal bigger than a ton has to support itself with legs directly under its body, not
05:07out to the side, otherwise it wouldn't have the strength to stand up.
05:12Once the toraton had changed its gait to accommodate this, it could get bigger and bigger.
05:18The swamp is a massive area where land meets water, and it's here that the creatures of
05:32the land meet the creatures of the water.
05:40The toraton spends most of its time reaching up for vegetation in the treetops.
05:46But there's something down at ground level that the toraton hasn't seen...yet.
05:55A family of swampus.
06:03They look like octopuses, and they're descended from octopuses.
06:11But this warm, humid world gives these swampus the chance to spend more time on land, at the
06:17risk of being trampled by an elephant-sized tortoise.
06:23the swampus has a deadly bite, a venom so powerful it's lethal even to something as big as a toraton.
06:30The swampus has a deadly bite, a venom so powerful it's lethal even to something as big as a toraton.
06:36The venom is a neurotoxin.
06:51It attacks the toraton's nervous system, first paralyzing it, then suffocating it as the toraton's lungs stop working.
06:58The venom is a neurotoxin.
07:02It attacks the toraton's nervous system, first paralyzing it, then suffocating it as the toraton's lungs stop working.
07:10The swampus inherits its deadly bite from its ancestors.
07:35All octopuses today are venomous to some extent, using poison to kill their prey.
07:53Some are just venomous enough to stop their victims struggling.
08:04And others, like the blue ringed octopus, have a venom ten thousand times more powerful than cyanide.
08:11Surely a case of overkill.
08:27In the future, such a powerful poison has also become a defensive weapon.
08:32So the swampus can meet the new challenges of life out on the land.
08:43Along the way, it's had to adapt to a terrestrial existence and be able to actually move around and live out of the water.
08:50How does it do that? How does an octopus live out of the water?
08:54Now, we know that even modern-day octopuses can do that.
08:57If you've ever seen one escaping from a marine tank, it will climb up the corner and down the side and across the floor and back into the sea.
09:04So, just by pulling themselves arm by arm along, we know that octopuses can deal with a terrestrial mode of locomotion.
09:14Moving on land is only one problem. The octopus also has to breathe in air.
09:21But one thing that a modern octopus can't do right now is breathe out of the water.
09:28And that's one of the major adaptations that these swamp octopuses will have had to have invented.
09:35A specialised lining on the inside of the body cavity has a very rich blood supply, like a lung.
09:47So the swampus can breathe in the humid air, to some extent.
09:53To move on land, four of its arms have become runners, allowing it to haul itself across the mud with the other four arms.
10:02It may look strange, but there are such halfway creatures today.
10:07A lot of animals have adapted from aquatic habitats to terrestrial ones.
10:12And we might think of that transition hundreds of millions of years ago,
10:15when amphibians first crawled up on land and began their terrestrial existence.
10:20But we don't have to go that far back, because we have modern examples of that now.
10:24Mudskippers, walking catfish.
10:27Mudskippers are very strange creatures.
10:30They're fish that can leave the water, pulling themselves along by muscular fins.
10:37They can breathe out of water, through their skin.
10:41And some mudskippers can survive more than two days on land.
10:50But for a mudskipper to survive in air, it has to keep its skin wet, so it never moves too far from water.
11:09In all those cases, what we see is a tie to the aquatic habitat, either for breathing or for reproduction.
11:18And the same is true of our octopus. They can't get very far from the swamp.
11:22They're tied to the water that they have to go back to to replenish their oxygen supply.
11:27In the future, there's a very good reason for the swampers to venture out onto land, to raise their young.
11:40The baby swampers are kept in a nursery inside this plant, where they're fed and protected.
11:47The youngsters of this octopus are perfectly good prey items.
12:12But by clustering them all together within what amounts to a nursery inside of this place,
12:17the adult octopuses, which have a venomous bite, can gather around and protect the young octopi.
12:24They can bring in food to feed to them and, in a sense, keep an eye on them.
12:28You may think that we have just, in this reconstruction, invented a piece of science fiction.
12:33No, all we've done is changed the players and shown you something that's going on at this very instant on this planet.
12:39Now, if one goes to the island of Jamaica, for example, you can observe a particular terrestrial crab
12:45that lives in the funnel-shaped leaves of a pineapple relative called a bromeliad.
12:56The plant traps rainwater, a private pool in which the bromeliad crab raises her young.
13:02She even catches food for them.
13:18In the future, several related swampus females all work together to raise their young and defend their nursery plant.
13:31But there's another reason for raising their young in the plant.
13:34It provides the young swampus with something they need.
13:40The plant vase, the water bowl, contains within it, as well as the octopi, a bacterium.
13:46And the bacterium is a creature which generates a toxin.
13:50As it turns out, the baby octopi are not affected by this toxin and, indeed, ingest it.
13:56And it becomes the basis for their venomous bite as they grow up and become adults.
14:01Well, we've discussed what's in it for the amphibious octopus.
14:04But in a co-evolutionary relationship that has to work in both directions, what's in it for the plant?
14:09The plant has timed its flowering so it occurs at the same time when the octopi are nursing their young.
14:16Which means that when the flower stalk emerges from the center of this large bowl,
14:20that no herbivore is going to bother it because there are the guardian octopi around the outside guarding their young.
14:27And so the process of fertilization and pollination can take place up on the top of the flower without disturbance,
14:34without anything destroying it.
14:37Every swampus in the neighborhood needs a nursery plant to breed in.
14:44This is an intruder, a stranger, another female looking for a nursery plant of her own.
15:00But the family won't give up their plant easily.
15:07They try to intimidate the intruder, waving their arms, flashing bright colors, showing that they're big enough and strong enough to defend their plant and themselves.
15:30The intruder gives up. There's no point in getting into a fight when she's outnumbered.
15:35Her only way out is back into the water.
15:41But there's a creature here that's found a way around the swampus venom.
15:54This is a lurk fish.
15:56And it's one of the few creatures that can kill a swampus.
16:00In the murky water, the lurk fish can't see very far, but it can sense the swampus as far as five meters away.
16:15It surrounds itself with a weak electric field and feels the swampus moving through the field.
16:20But electricity has a more sinister use.
16:29As the swampus gets closer, the lurk fish stuns it with a massive electric shock.
16:35Our lurk fish in this environment is using an electrical sense to detect prey from a distance.
16:50But it's also using that same ability to stun prey and immobilize them.
16:55Now, currently, that's a very common strategy in similar freshwater fish like electric catfish.
17:03Electric catfish use electricity to kill the smaller prey.
17:07But the electric eel can pack up to 600 volts, enough to stun a human.
17:17The eel senses its prey in the water with a weak electrical discharge,
17:22and then releases a much higher voltage to shock and stun it.
17:38Electric fish now generate voltage in small blocks, small muscle blocks along the length of the fish,
17:44each generate a small electrical potential.
17:47And like batteries in a series, those muscle blocks along the length build up a bigger and bigger charge.
17:55The lurk fish takes this even further.
17:58It's over four meters long and has huge numbers of muscle blocks packed along its body,
18:03which build up a massive electrical charge.
18:09In a matter of seconds, it generates a thousand volts.
18:17By generating such a powerful charge, the lurk fish can stun something as big,
18:22and venomous, as the swampus, before it has a chance to fight back.
18:36With the swampus dead in the water, the lurk fish doesn't have to worry about the venomous bite.
18:41With something as deadly as a lurk fish hiding in the murky water, dry land seems much safer for a swampus.
18:59But even here, there are problems.
19:01Something is coming.
19:06Something is coming.
19:08Something big.
19:16A herd of toratons.
19:18Adult toratons.
19:19The one the swampus family killed was only a baby.
19:32These are fifteen times bigger.
19:36The adults are enormous.
19:38The biggest animals that have ever walked on the face of the planet.
19:41A hundred and twenty tons.
19:43That's bigger than even the biggest dinosaur.
19:45Now, there are lots of advantages about being so big.
19:49They're far too big for swampuses to kill.
19:53Adult toratons have no predators.
19:56But they're also big because they eat vegetation.
19:59And not only so they can reach high up into the treetops.
20:03When you're eating all this vegetation, you need to ferment it to get all the goodness out of it.
20:08You need an enormous stomach.
20:10A big barrel-shaped stomach.
20:12And the bigger the animal is, the bigger its stomach's going to be.
20:15So it can extract all the goodness out of all the vegetation over several days.
20:23So size really does matter.
20:26Animals this big can just move from tree to tree, stripping off the leaves.
20:30But size also creates problems.
20:34Of course, there is one major problem about being so huge.
20:39And that's when it comes to mating.
20:41Now, modern day tortoises mate on top of each other.
20:44But of course, a toraton is far too big for that.
20:47The female will not be able to support a hundred and twenty tons on the back during mating.
20:51We'll solve this problem by mating back to back.
20:53They're simply backing to each other and they're face away from each other during courtship and mating.
21:13During the actual mating, when they are back to back,
21:16the male and the female raise their tail to reveal the cloaca.
21:19And the two cloacas actually touch and that's when the sperm is transferred from one to the other.
21:23That's the only physical contact they have during mating.
21:30It takes a long time for a toraton to grow to full size.
21:34And they live in family groups, protecting their young for 30 years.
21:38But one of their babies is missing and the herd is restless.
21:52They don't know their youngster has been killed by a swampus, so they're not out for revenge.
21:57But their search does take them into an area where the swampus are raising their young and where the baby died.
22:14For the toratons, the nursery plant is just another bit of vegetation in the way.
22:18One careless kick and the plant is destroyed.
22:25But where are the young swampus?
22:27They're old enough now to have been taken to safety, a branch over the swamp.
22:42Out of reach of the toraton's big feet and the lurk fish.
22:49But before they can drop into the water, their mother has to distract the lurk fish,
22:54deliberately drawing it away from the babies.
22:57Staying out of range of its deadly electric shocks.
23:00Once far enough from shore, the agile swampus hides herself in the vegetation,
23:20keeps still and so loses the lurk fish.
23:24She's bought the babies enough time to find a safe hiding place in the water.
23:45A vast swamp where the land meets the water.
23:49A rich, fertile place in a constant, warm, wet climate.
23:55With such benign conditions, evolution has run riot.
24:00New animals have moved onto land and formed a partnership with a plant.
24:07A giant fish hunts and kills by electricity.
24:13And, towering above it all, the biggest creatures ever to walk the earth.
24:21The
24:31water.
24:38through the power.
24:40We'll see you next time.
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