Documentary, The Future Is Wild - Return to the Ice-2- 2002
#AncientEarth #Documentary #Dinosaurs #Prehistoric #Evolutionary
#AncientEarth #Documentary #Dinosaurs #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.
00:58Five million years in the future. This is Europe, but nothing seems familiar.
01:05The Atlantic coast of France is buried under ice sheets over a kilometer thick.
01:11The familiar animals have also disappeared.
01:13Instead, creatures we wouldn't recognize are roaming across the icy wilderness.
01:18The animals have also disappeared.
01:20These are shag rats.
01:21The Atlantic coast of France is buried under ice sheets over a kilometre thick.
01:32The familiar animals have also disappeared.
01:36Instead, creatures we wouldn't recognise are roaming across the icy wilderness.
01:46These are shag rats.
01:48And at the end of the long winter, they migrate to the edge of the ice sheets looking for grazing.
01:57Shag rats are about a metre high.
02:00They stay together in big herds, partly as protection against the cold and partly against predators that hunt in this bleak landscape.
02:11This is how northern Europe will look in a future ice age.
02:18Throughout an ice age, the ice sheets retreat and advance in a pattern.
02:24In the future, they will return again and again, grinding their way down from the poles, reaching as far south in Europe as Paris.
02:32South of the ice sheets, most of the rest of Europe has become frozen tundra, and the orchards and vineyards have long gone.
02:47It's hard to survive in such a bleak, cold landscape.
02:55But life hangs on.
02:59And more than that, some creatures thrive here.
03:02Especially those that can live on these tough, cold adapted shrubs.
03:05These herds have to cover large distances each day to find these sparse patches of grazing.
03:20But the biggest problem in surviving when the ice age returns is how quickly the climate changes, making it hard for evolution to keep up.
03:36Animals that do survive ice ages tend to develop a number of features in common.
03:40They have long fur, obviously, and plenty of fat to keep warm.
03:45They tend to have chunky body forms.
03:47They tend to have small ears, short tails and short legs.
03:51On this barren landscape, we have a large herbivore.
03:54It's a shag rat.
03:55It's a rodent.
03:56It's evolved from an animal like a marmot.
03:59It lives in groups of about a dozen animals.
04:02They survive the cold conditions by huddling together for warmth.
04:04They have thick fat, short legs, all adaptations survive in cold climates.
04:13The ancestors of shag rats were creatures like marmots.
04:18Today, they live on the cold, high mountain pastures of Europe.
04:24Marmots are rodents.
04:27And rodents are nature's great survivors.
04:29They're versatile.
04:30They can eat just about anything and live just about anywhere.
04:49And rodents breathe very quickly, allowing evolution to keep up as the climate changes.
04:54And as Europe was plunged into a new ice age, these shag rat ancestors found ways to fend off the bitter cold.
05:06One way to survive in a cold climate is to get bigger, reducing the surface area relative to volume, which means less body heat is lost.
05:16Shag rats stand three times taller than their ancestors, the marmots.
05:21They also have a specially warm, shaggy coat, made up of two layers of fur.
05:32A dense underfur traps a layer of warm air next to the body as insulation.
05:38And long, waterproof guard hairs keep this fur dry.
05:41These guard hairs are hollow, and the air inside provides extra insulation.
05:49So the shag rat is doubly insulated against the worst of the ice age winters.
05:54At the edge of the ice sheet, the temperature can plunge to minus 60 degrees, and sudden blizzards seem to come from nowhere, sweeping across the tundra.
06:06Instead of hibernating like their marmot ancestors, the shag rats stay active all winter, travelling long distances through the snow in their search for food.
06:23Winds of 80 kilometres an hour whip up the dry snow into a total whiteout.
06:31In just a few minutes, a storm can reduce visibility to zero.
06:36Now the shag rats are in real danger.
06:51Not from the blizzard, the powerful stocky shag rats can survive much worse than this.
06:56But from a predator, a snow stalker, that uses the snow storm as a cover, stalking close to the herd.
07:07If a shag rat gets tired, ill or weak, and falls behind the others, it's in serious trouble.
07:16The shag rat is only wounded, but the snow stalker doesn't risk injury by trying to finish it off.
07:39There's no rush. It simply trails its victim and waits until the shag rat bleeds to death.
07:49The snow stalker belongs to a family of vicious predators.
08:11They are the musterlids, the weasel family.
08:17And the largest is the wolverine.
08:29The wolverine is an all-round scavenger and predator.
08:33It'll eat anything it can find and kill.
08:35So wolverines are more likely than many to survive and adapt to the coming ice age.
08:50To hunt and kill prey larger than themselves, snow stalkers are bigger and heavier than their wolverine ancestors.
09:01But they attack their victims by a method that's been used before in previous ice ages.
09:07Razor sharp sabre teeth.
09:09Previously, some of the cats have evolved sabre teeth and they used them to kill their prey in a similar way.
09:17The sabre toothed cats would attack big prey even up to the size of a mammoth and inflict severe injuries on them and let them die from their wounds.
09:25This is the first time that another group of carnivores had evolved sabre teeth.
09:28Snow stalkers also have hairy soles to their feet to insulate them from the cold and give them some grip on the slippery ice.
09:40As long as there are shad rats on the snow fields, the snow stalkers have a good supply of meat.
09:49They're normally solitary, but this is a female, and as well as finding enough to eat herself, she has to take food to her cubs.
10:09Her den is in a shallow cave, the only shelter she can find in this bleak landscape.
10:15Even at this age, the cubs are ferocious and competitive.
10:35But they're growing fast, and to give them enough to eat, their mother has to move on, searching for more food.
10:41She'll travel tens of kilometers from the den, even as far as what was once the French coast.
10:54Here, glaciers, once confined to the mountain tops, now reach down to the sea.
11:00For only a few brief summer months, the sea and the beaches are free of ice.
11:13And then it's worth the long walk for the snow stalker.
11:16There's the possibility of food on the beach.
11:23Gannet whales, three meter long, ungainly looking creatures, are lolling on the shingle.
11:30Despite their size, they're actually birds, evolved from gannets.
11:47Gannets are very common seabirds.
11:49In the northern hemisphere, they tend to live in large colonies, often on sea cliffs.
11:55They're active predators chasing fish.
11:58Now, many birds chase fish.
12:00But the gannet is unusual, because it dives into the water and then swims underwater with its wings.
12:06It's a bit of a compromise.
12:08It's got to be a good flying bird and a good swimming bird.
12:13These are difficult things to get right.
12:15Water is 800 times denser than air.
12:19Density above all is what determines how you move.
12:22Moving in both mediums is very hard.
12:27The gannets' compromise is to tuck their wings into their bodies when underwater, turning them into makeshift flippers.
12:34It works, but not very well.
12:42The gannet whale has given up flying completely, so its wings can evolve just for swimming, like flippers on a sea lion or penguin.
12:54So it can travel at high speed underwater.
12:57And to steer, its feet have become rudders.
13:04Gannet whales now live in the same way as the big marine mammals once did.
13:09But that couldn't happen if marine mammals were still around.
13:13So what happened to them?
13:15In today's seas, there are whales of all shapes and sizes.
13:23Large baleen whales, like these humpbacks, catch enormous quantities of tiny food from the water.
13:30Sitting plankton and small fish through huge plates in the sides of their mouths.
13:34And smaller, toothed whales, like dolphins, chase and catch individual fish.
13:44They use concentrated sound beams to locate fish, and perhaps even use sound to stun them.
13:51But whales and dolphins have one thing in common.
14:13These are animals which today are extraordinarily vulnerable to human interference.
14:22They're being affected by climate change, by excessive fishing, habitat change, pollution.
14:28A whole range of threats, but it seems almost impossible for these animals to survive more than a few tens of thousands of years into the future.
14:37By five million years' time, all the marine mammals will have become extinct.
14:43Now that's bad news for the marine mammals.
14:46It's good news for other animals which might be able to evolve into those niches.
14:50The niches which are left free are wide open for birds like the gannet whale to exploit.
14:56Gannet whales took the place of the smaller toothed whales, using their long serrated bills to catch fish.
15:04But there's still a big difference between dolphins and gannet whales.
15:14The major feature of marine mammals is that they give birth to live young,
15:19and that by doing that they're able to complete most, if not all, of their life cycle in water.
15:25Whales and dolphins never need to come onto land.
15:29Birds, this is different.
15:30Birds lay eggs, and eggs can't be dealt with in water.
15:37So every summer, the gannet whales leave the water and haul themselves onto the beach.
15:48There they lay and incubate a large single egg.
15:53The problem is it's a large bird.
15:57That means it's got a long time in which it hatches the egg,
16:01and then subsequently raises the young up to the stage where the young can fend for itself.
16:06That takes time and takes a complicated life cycle.
16:10We can see similar things in many modern birds.
16:13Albatrosses and penguins have to face exactly the same problems.
16:16Emperor penguins take a long time to incubate their eggs, and they do it out in the open,
16:25on the icy wastes of Antarctica.
16:32They don't build a nest.
16:35Instead, the female lays the egg and then passes it to the male.
16:39He balances the egg on his feet and covers it with a fold of warm skin.
16:57Then the females leave, and the males are left behind to endure the coming Antarctic winter.
17:02At the end of the long, dark winter, the chicks hatch, the females return to feed them.
17:26The chick is transferred between the parents' feet to keep it off the ice.
17:37The chick is transferred between the parents' feet to keep it off the ice.
17:40From now on, both parents will take turns returning to the sea to bring back food for the growing chick.
18:05In the future, the gannet whale also cradles its egg on its large, upturned feet.
18:16During the summer breeding season, the feet themselves had a rich blood supply,
18:23which keeps them warm and in turn warms the huge egg.
18:26But an egg this big would make a perfect meal for a snowstalker.
18:37Snowstalkers have a very keen sense of smell, and can find food from some distance away.
18:42So gannet whales always haul up in groups for defence.
18:56It will be hard to get past those powerful beaks, as long as the gannet whales stay close together.
19:13The snowstalker won't give up easily.
19:26And for a really persistent snowstalker,
19:43Gannet Whales have a second line of defence.
19:55Uh huh.
20:01And for a really persistent snowstalker,
20:04Gannet whales have a second line of defence.
20:07Vomiting up a disgusting, foul-smelling mixture of partly digested fish and squid.
20:19Just too much for the snow stalker's sensitive nerves.
20:37Summer is short, cold and bleak near the edge of the great European ice sheet.
20:51There are only a few brief summer months when the shag rats can graze on fresh green vegetation without digging through snow.
21:07In five million years' time, the plants and insects living in what was once France and Germany will be similar to those that today live north of the Arctic Circle.
21:19But summer is all too short, and autumn brings the return of the freezing weather.
21:38The mother snow stalker has brought her two cubs out of the den and has to teach them how to survive on their own.
21:57A mother has to train her young how to hunt. It's difficult, it's risky.
22:02So you might see two or three animals hunting together. That's a mother training her offspring.
22:07and she'll show the offspring how to run, inflict the injuries on the shag rats, then back off and wait for the animal to die.
22:24The mother watches the youngsters struggling to bring down the shag rat.
22:27But eventually, she shows them how it's done.
22:45If she teaches them well, they'll stand a chance of surviving their first Ice Age winter.
23:06Now the temperature plummets to minus seventy degrees, and the vegetation is buried under meters of snow.
23:21This is the hardest time for the shag rat herds.
23:28They migrate south as far as they can go, but the weather won't improve much.
23:33And they'll be followed every step of the way by snow stalkers.
23:37In five million years time, the return of the Ice Age is a serious challenge to life.
24:00Many of today's familiar creatures have gone, unable to keep up with the changing climate.
24:09But life is resilient, and evolution has responded to the challenge, with new creatures at home in this icy wilderness.
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