The Future is Wild (2003) s01e02 Episode Script

Return of the Ice

Imagine a world millions of years in the future, a world where evolution has written a new chapter in the story of life.
The world is inhabited by very strange creatures, like nothing the Earth has ever seen.
the FUTURE is WILD Return Of The ICE Five million years in the future.
This is Europe, but nothing seems familiar.
The Atlantic coast of France is buried under ice sheets over a kilometre thick.
The familiar animals have also disappeared.
Instead creatures we wouldn't recognise are roaming across the icy wilderness.
These are Shag Rats, and at the end of the long winter, they migrate to the age of the ice sheets looking for grazing.
Shag Rats are about a metre high, they stay together in big herds, partly as protection against the cold and partly against predators that hunt in this bleak landscape.
This is how northern Europe will look in a future ice age.
Throughout an ice age the ice sheets retreat and advance in a pattern.
In the future they will return again and again, grinding their way down from the poles, reaching as far south in Europe as Paris.
South of the ice sheets, most of the rest of Europe has become frozen tundra and the orchards and vineyards and have long gone.
It is hard to survive in such a bleak, cold landscape.
But life hangs on, and more than that, some creatures thrive here, especially those that can live on these tough cold-adapted shrubs.
These herds have to cover large distances each day to find these sparse patches of grazing.
But the biggest problem in surviving when the ice age returns is how quickly the climate changes, making it hard for evolution to keep up.
Animals that do survive ice ages tend to develop a number of features in common.
They have long fur, obviously, and plenty of fat to keep warm, they tend to have chunky body forms, they tend to have small ears, short tails, and short legs.
On this barren landscape we have a large herbivore, it is a Shag Rat.
It is a rodent, it has evolved from animal like a marmot, it lives in groups of about a dozen animals, they survive the cold conditions by huddling together for warmth, they have thick fat, short legs: all adaptations surviving in cold climates.
The ancestors of Shag Rats were creatures like marmots.
Today, they live on the cold high mountain pastures of Europe.
Marmots are rodents, and rodents are nature's great survivors.
They are versatile, they can eat just about anything and live just about anywhere.
And rodents breed very quickly, allowing evolution to keep up as the climate changes, and, as Europe was plunged into a new ice age, these Shag Rats' ancestors found ways to fend-off the bitter cold.
One away to survive in a cold climate is to get bigger, reducing the surface area relative to volume which means less body heat is lost.
Shag Rats stand three times taller than their ancestors, the marmots.
They also have a specially warm shaggy coat, made up of two layers of fur.
A dense under-fur traps a layer of warm air next to the body as insullation; and long, waterproof guard hairs keep this fur dry.
These guard hairs are hollow and the air inside provides extra insullation so the Shag Rat is doubly insulated against the worst of the ice age winters.
At the edge of the ice sheet, the temperature can plunge to -60° and sudden blizzards seem to come from nowhere, sweeping across the tundra.
Instead of hibernating like their marmot ancestors, the Shag Rats stay active all winter, travelling long distances through the snow in their search for food.
Winds of 80 kilometres an hour whip up the dry snow into a total whiteout.
In just a few minutes, a storm can reduce visibility to zero.
Now the Shag Rats are in real danger.
Not from the blizzard: the powerful, stocky Shag Rats can survive much worse than this, but from a predator, a Snow Stalker that uses the snow storm as a cover, stalking close to the herd.
If a Shag Rat gets tired, ill or weak and falls behind the others, it is in serious trouble.
The Shag Rats is only wounded but the Snow Stalker doesn't risk injury by trying to finish it off.
There is no rush, it simply trails its victim and waits until the Shag Rat bleeds to death.
The Snow Stalker belongs to a family of vicious predators.
They are the mustelids, the weasel family.
And the largest is the wolverine.
The wolverine is an all round scavenger and predator, it will eat anything it can find and kill.
So wolverines are more likely than many to survive and adapt to the coming ice age.
To hunt and kill prey larger than themselves, Snow Stalkers are bigger and heavier their wolverine ancestors, but they attack their victims by a method that has been used before in previous ice ages, razor sharp sabre teeth.
Previously some of the cats have evolved sabre teeth and they will use them to kill their prey in a similar way.
The sabre tooth cats would attack big prey even up to the size of mammoth and inflict severe injuries on them and let them die from their wounds.
This is the first time that another group of carnivores have evolved sabre teeth.
The Snow Stalkers also have hairy soles to their feet to insulate them from the cold and give them some grip on the slippery ice.
As long as there are Shag Rats on the snow fields, the Snow Stalkers have they good supply of meat.
They are normally solitary, but this is a female and as well as finding enough to eat herself, she has to take food to her cubs.
Her den is in a shallow cave, the only shelter she can find in this bleak landscape.
Even at this age the cubs are ferocious and competitive.
But they are growing fast and to give them enough to eat, their mother has to move on, searching for more food.
She will travel tens of kilometres from the den, even as far as what was once the French coast.
Here glaciers, once confined to the mountain tops, now reach down to the sea.
For only a few brief summer months, the sea and the beaches are free of ice.
And then it is worth the long walk for the Snow Stalker.
There is the possibility of food on the beach.
Gannetwhales, three metre long, ungainly looking creatures are lolling on the shingle.
Despite their size, they are actually birds, evolved from gannets.
Gannets are very common seabirds, in the northern hemisphere they tend to live in large colonies, often on sea cliffs.
They are active predators, chasing fish.
Now many birds chase fish, but the gannet is unusual because it dives into the water and then swims underwater with it's wings.
It is a bit of a compromise, it has got to be a good flying bird and a good swimmer.
These are difficult things to get right.
Water is 800 times denser than air.
Density, above all, is what determines how we move.
Moving in both mediums is very hard.
The Gannets' compromise is to tuck their wings into their bodies when underwater, turning them into makeshift flippers.
It works, but not very well.
The Gannetwhale has given up flying completely, so it's wings can evolve just for swimming like flippers on a sea-lion or penguin.
So it can travel at high speed underwater.
And to steer, its feet have become rudders.
Gannetwhales now live in the same way as the big marine mammals once did, but that couldn't happen if marine mammals were still around, so what happened to them? In today's seas, there are whales of all shapes and sizes.
Large baleen whales like these humpbacks catch enormous quantities of tiny food from the water, sieving plankton and small fish through huge plates in the side of their mouths.
And smaller, toothed whales like dolphins, chase and catch individual fish.
They use concentrated sound beams to locate fish and perhaps even use sound to stun them.
But whales and dolphins have one thing in common.
These are animals which today are extraordinarily vulnerable to human interference, they are being affected by climate change, by excessive fishing, habitat change, pollution, a whole range of threats that it seems almost impossible for these animals to survive for more than a few tens of thousands of years in the future.
By five million years' time, all the marine mammals will have become extinct.
Now that is bad news for the marine mammals but it is good news for other animals which might be able to evolve into those niches.
The niches which are left free are wide open for birds like the Gannetwhales to exploit.
Gannetwhales took the place of the smaller, toothed whales, using their long, separated bills to catch fish.
But there is still a big difference between dolphins and Gannetwhales.
The major feature of marine mammals is that they give birth to live young and that by doing that, they are able to come complete most, if not all, of their life cycle in water.
Whales and dolphins never need to come onto land.
Birds: this is different.
Birds lay eggs.
And eggs can't be dealt with in water.
So every summer, the Gannetwhales leave the water and haul themselves on to the beach.
There they lay and incubate a large, single egg.
The problem is it is a large bird, that means it has got a long time in which it hatches the egg and then subsequently raises the young up to the stage where the young can fend for itself.
That takes time and takes a complicated life cycle.
We can see similar things in many modern birds.
Albatrosses and penguins have to face exactly the same problems.
Emperor penguins take a long time to incubate their eggs and they do it out in the open on the icy wastes of Antarctica.
They don't build a nest.
Instead, the female lays the egg and then passes it to the male.
He balances the egg on his feet and covers it with a fold of warm skin.
Then the females leave and the males are left behind to endure the coming Antarctic winter.
At the end of the long, dark winter, the chicks hatch, the females return to feed them.
The chick is transferred between the parents' feet to keep it off the ice.
From now on, both parents will take turns returning to the sea to bring back food for the growing chick.
In the future, the Gannetwhale also cradles it's egg on it's large, upturned feet.
During the summer breeding season, the feet themselves have a rich blood supply which keeps them warm and in turn, warms the huge egg.
But an egg this big would make a perfect meal for a Snow Stalker.
Snow Stalkers have a very keen sense of smell, and can find food from some distance away.
So Gannetwhales always haul up in groups for defence.
It will be hard to get past those powerful beaks, as long as the Gannetwhales stay close together.
The Snow Stalker won't give up easily.
And for a really persistent Snow Stalker, Gannetwhales have a second line of defence.
Vomiting up a disgusting, foul smelling mixture of partly digested fish and squid.
Just too much for the Snow Stalker's sensitive nose.
Summer is short, cold and bleak near the edge of the great European ice sheet.
There are only a few brief summer months when the Shag Rats can graze on fresh, green vegetation without digging through snow.
In 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.
But summer is all too short, and autumn brings the return of the freezing weather.
The mother Snow Stalker has brought her two cubs out of the den and has to teach them how to survive on their own.
A mother has to train her young how to hunt, it is difficult, it is risky, so you might see two or three animals hunting together.
That is a mother training her offspring.
And she will show the offspring how to run, inflict the injuries on the Shag Rats then back off and wait for the animal to die.
The mother watches the youngsters struggling to bring down the Shag Rats.
But eventually, she shows them how it is done.
If she teaches them well, they will stand a chance of surviving their first ice age winter.
Now the temperature plummets to -70° and the vegetation is buried under metres of snow.
This is the hardest time for the Shag Rat herds.
They migrate south as far as they can go, but the weather won't improve much and they will be followed every step of the way by Snow Stalkers.
In five million years' time, the return of the ice age is a serious challenge to life.
Many of today's familiar creatures have gone unable to keep up with the changing climate.
But life is resilient and evolution has responded to the challenge with new creatures, at home in this icy wilderness.