The Living Planet

The planet on which we live is in a state of perpetual change.

From cracks in its surface, molten rock is continually erupting.

The forces that drive this lava to the surface also cause the continents

to move round the globe, millimetre by millimetre, over thousands of years.

When they collide, the buckling, contorted rocks are pushed up

into great mountain ranges.

But just as they rise, so are they cut down by the erosion of ice

and snow and rushing water.

At the poles, where the sun's rays strike the glob only obliquely, it's bitterly cold.

Here glaciers grind their way across the land, gouge out deep valleys

and flow down into the sea.

At the equator, where the sun strikes the earth four-square, the land is baked.

Over centuries, the amount of rain falling on it has varied.

As it diminishes, so the forests have dwindled and been

replaced by grassland.

And grassland, if it dries still further, turns to desert.

Throughout all these changes, living creatures have evolved

with a speed that has matched that of the changing landscape.

In the hot deserts, animals have evolved ways of living in oven-like temperatures

without drinking any liquid whatsoever.

In the cold deserts around the poles, other creatures, with the ability to

generate their own internal heat, have grown insulating coats

of fur and fat so that they are not frozen to death.

Human beings, one of the last species of large animal to appear on the planet,

have spread with extraordinary speed to all corners of the globe.

They've be able to do so not so much because their bodies have changed to

match different extremes but because they've used their skills

and intelligence to exploit the adaptations of other living creatures.

The Eskimos survive in the Arctic by keeping themselves warm

with the skins of polar bears and seals.

In the equatorial jungles of the Amazon, the Indians have learned where to find

and how to collect everything they need to sustain themselves.

Even though today they may cook in metal pots traded from the

outside world, they still know how to make pottery from the clay.

In the hot deserts of southern Africa, the Bushmen survive droughts

by tapping the stores of liquid held in the bodies of animals

and the roots and the stems of plants.

Immediately after the rains, however, they can collect water

from natural hollows,but even that takes knowledge and skill.

Indeed, human beings, for nearly all the half-million year of their

existence as a species, have lived simply by gathering wild plants

and hunting wild animals.

And 10,000 years ago, people were doing so here in the Middle East,

just as they were everywhere else.

In these forests, there's quite a lot to eat:

There are pistachio nuts and wild almonds and acorns and juniper berries.

And 10,000 years ago there were quite a lot of wild animals:

Wild goat, wild pig, wild horses, giant wild cattle and gazelle.

Even so, there are hardships to be endured. There could be torrential rains.

At night it can get crushingly cold and there could be snow.

And during the day it gets bakingly hot.

But about 9,000 years ago, man took a crucial step.

Until then, the environment through evolution had shaped his body,

as it had shaped the bodies of all animals.

But now, uniquely, man turned that around.

He began to change the environment to suit himself,

and one of the places where he first did so is in that valley down there.

This is Beidha in Jordan, and here were found the remains of one of

mankind's earliest villages.

This was no temporary encampment, but a permanent settlement

with alleys and houses of stone built adjoining one another.

They were half-dug into the ground, the floor and walls were covered with

a plaster of mud and lime,

and in the walls there were posts which supported a roof of thatch

which probably just cleared the top of the wall so that light could get inside.

So the people had created a snug home, protected from the rain and the sun,

a place where mothers could bear their children in safety.

There are lots of grinding stones, querns, here, in which the people

ground the seeds of grass,

a kind of wild barley that grows abundantly hereabouts.

They'd long since discovered that you could take such grass seeds

and scatter them on the ground and produce a crop.

Indeed, hey'd been doing just that with the seeds of another wild grass,

wheat, for many centuries.

And now they were settled, it was inconvenient to have to scour the

countryside to look for places where the grass just happened to grow.

Much better to throw it onto the ground nearby the village, where they

could watch the growing crop, make sure that wild animals

didn't plunder it, and where it was convenient to gather.

So these people became farmers.

The people were also meat-eaters, and in this one small chamber

have been found great quantities of the bones of wild goat, like this.

Domesticating animals must have been very much more difficult than

domesticating plants.

But in fact, the first steps towards doing so were probably taken

many centuries earlier when the people were still nomads.

A way in which that might have happened can be seen going on today

amongst the Lapp peoples in Scandinavia.

This is the most northerly living of all deer.

It's found right round the Arctic wherever there is land.

In America, it's called the caribou, in Europe, reindeer.

In North America the caribou are completely wild,

but here in northern Scandinavia they are, to some degree at least,

domesticated.

Man has managed to achieve that by becoming a nomad himself.

The reindeer during the winter have to keep on the move in a continuous

search for something to eat, and the Lapps, they want to keep an eye on

their herd and maintain their possession to it, have to move with them.

Traditionally, they do so on skis. Indeed, skis originated in this part

of the world.

But today the herdsmen are fully up to date with modern technology.

The reindeer's winter food is a kind of lichen which they find

growing beneath the snow.

When the reindeer were completely wild, young stags as they mature

would wander away from their parntal group, taking a few

young females with them.

But the Lapps regarded the offspring of their herd as their property.

So to prevent them being lost, they castrated the young males.

The few they left unmutilated in order to breed were those they

thought most likely to remain unaggresive and disinclined

to wander, even when adult.

So, consciously or unconsciously, the Lapps over centuries have

changed the reindeer from a nervous creature living in small family groups

to one that is so docile it can be kept in herds thousands strong

and can be moved from one snow slope to another simply by leading

the way with a stag on a halter.

It may well be that in some such way as this, the people who lived

9,000 years ago in the village of Beidha gradually turned the wild

goats of the surrounding mountains into tamed domesticated ones.

The techniques of domestication and maybe the domesticated

animals themselves slowly spread westwards across Europe.

7,000 years ago, the people living in France had their own herds.

And around 6,000 years ago, the techniques and even perhaps

the herdsmen with some of their stock crossed the channel into Britain.

They must have landed somewhere in southern England,

but the land they found didn't look like this.

Like nearly all the rest of Britain, it was covered in trees.

There were people already here living in the forests, gathering fruit and nuts

and hunting the wild animals, deer and wild oxen.

But they hadn't changed the woodlands of Britain

any more than the Amazonian Indians have changed the jungle.

But these new arrivals did. They began to clear the forests

to make way for their farms.

So this landscape of the South Downs is not natural. It's their creation.

The people cut down the forests with stone axes.

And then the teeth of their flocks kept the land open.

Grazing sheep still prevent the seedlings of trees from growing

and keep the pastures clear for cowslips and clover, orchids and

buttercups, pipits and skylarks.

This was the beginning of a process that was to transform Britain.

Much of our apparently wild landscape is in fact man-made.

The Norfolk Broads, that wilderness of shallow lakes, reed beds and

winding waterways, are not natural basins but vast pits, dug by men

collecting peat some 600 years ago, that have subsequently flooded.

Many of the upland moors of northern England and southern Scotland

were cleared of their forests thousands of years ago,

but during the 19th century men encouraged heather to grow there

by setting light to the moors by regular intervals,

for heather is the food of grouse,

and men want flocks of grouse for their guns.

Indeed, almost the only part of Britain that remains free of human influence

is the land over 2,500 feet high that is of little practical use to people.

It was scraped clean of soil by glaciers during the Ice Age 10,000 years ago

and still remains stony and barren.

As we transformed the landscape, of Britain, so we also rapidly

altered the community of animals that lived here.

Those that didn't suit us, we got rid of.

Brown bears were once common, but they were regarded as dangerous

and they could give good sport if they were baited with dogs

The last British bear was killed in the 10th century.

Wolves preyed on domesticated flocks and herds and even

threatened people.

The last English wolf had been killed by the year 1500

and the last Scottish one by the middle of the 18th century.

Beavers were hunted not so much because of the damage they did

to the woodlands, but because their fur was so highly valued.

They had all gone by the 13th century.

Wild boar were once common in British woods,

grubbing up roots and bulbs, munching acorns and beech nuts.

But boars could be aggressive and dangerous, and the sows

and particularly the piglets made good eating.

By the 17th century, there were none of these left either.

The elk, known in America as the moose, once lived here too,

but it had been hunted into extinction even before the Romans arrived.

Men also introduced animals to Britain.

The Normans brought fallow deer from Europe.

And rabbits.

At first these creatures were carefully guarded in enclosures,

for they were valued for their fur and meat.

They only became really common in the countryside during the 19th century.

Pheasants are Asian birds, and were brought here soon after

the Norman Conquest.

Other introductions, however, were unintentional and much less welcome.

The house mouse from the Mediterranean may well have been

the first animal of all to be brought to Britain by man,

for the Romans found it living in British villages.

And other,much bigger animals were living around the settlements

of those early British tribes.

Aurochs, the giant cattle whose images were painted on the walls of

French caves during prehistory, also roamed in British forests.

By Roman times, some had already been domesticated,

and one of the early strains derived from them still survives

in the Cheviot Hills.

This herd at Chillingham was penned in a great park during the 13th century,

and has lived here ever since, with scarcely any interference

from human beings.

The animals may well be very similar to those that wandered

around the farms during Roman times.

They're formidable animals, very different from the gentle

Friesian of today.