All language subtitles for The Living Planet s01e12 New Worlds.eng

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.

One great bull rules the herd.
He mates with all the cows

and fights every young male
who challenges him.

Eventually, after two or three years,

he will lose and surrender his place
to a younger, more vigorous animal.

Having changed a wild animal
into a relatively docile one by

selective breeding, farmers now
used the same techniques to modify

the animal's body.

They wanted meat, and soon they
produced a very different-looking

kind of beast.

These portraits, commissioned
by proud breeders 100 years ago,

show clearly that the characteristics
they valued in their cattle

then are the same as
those we prize today.

Today's bulls have such stunted
legs that they can't run fast

to chase away a rival.

Many don't even have horns
with which to fight a courtship battle.

But these won't be permitted
to mate with a cow anyway.

Their semen will be taken from them
and injected into cows by syringe,

so that each of them,
without moving from his stall,

may father thousands of offspring
on the other side of the world.

Under intensive feeding, such cattle
can put on two pounds a day

and grow so fast that they can be
profitably slaughtered within a year.

The new breeds of pig, direct
descendants of the wild boars of the

European forests, now grow five
times faster than their wild cousins

and are ready for slaughter
within only six months.

Turkeys are descended from wild
birds that lived in Central America.

They are produced entirely by
artificial insemination and have

been turned into creatures that
will live not in small family groups

but immense congregations.

Chickens,originally birds of the
Asian jungles, have been converted

into egg-producing machines
that can lay over 300 eggs a year.

The same techniques of selective
breeding produced our food plants,

using species from all over the world.

The potato came from the Andes,
where it was grown by the Incas.

The pea is a European plant
first cultivated by the Italians

in the 16th century.

Beans came from Mexico, rhubarb
from China, beetroot from Germany.

And this plant was first cultivated in
the seventh century in Afghanistan,

taken from there to North Africa,
then brought by the Moors into Europe,

where it was cultivated by the Dutch
to produce... this, a carrot.

But wild plants from the family
that is perhaps the most important

to man for food don't grow in this
allotment because they would be

regarded as weeds: The grasses.

The grass we call rice was
domesticated in Asia some

7,000 years ago, at about the same
time that people were learning

to cultivate wheat in the lands
around the Mediterranean.

Over the centuries, the people of
Asia have perfected the techniques

of growing one kind of
rice in flooded terraces.

And they do so with such skill
that the rice will flower and ripen

and produce heads of swollen
seeds several times a year.

As mankind's population grew,
so more and more of the land

had to be taken into cultivation.

Today, 11% of all the arable land
on earth is devoted to growing

just this one species of grass.

Now more than 2,000 million
people depend on it,

half the population of the world.

In the western world, people still prefer
the kind of grass they first learned

to eat during prehistory,
but that too they have transformed.

Today's wheat grows tall, uniform
and dense, so it can be easily

harvested by machines.

Selective breeding technics
has greatly increased its yield

Even since the 1940s, its
productivity has been doubled.

Today it bears ten times the weight
of seeds on each stem than does its

wild ancestor that still grows in
the parched lands of the Middle East.

But this change has a price.
Wheat like this can't even reproduce

itself now without man's aid.

It's true that it is largely immune
to pests like moulds and rusts,

but moulds and rusts
also evolve very quickly,

naturally, into form which
can attack the new strains.

So farmers have to change the
strain that they grow on average

about every ten years.

Today, in North America, over half
the wheat comes from just four strains.

Were plant breeders to fail to produce
new varieties from wild species,

then fields like this could be
devastated and the western world

would starve.

To grow the vast quantity of grain
needed by mankind's ever

increasing population, huge areas
of the most fertile lands on earth

have been turned over
to its cultivation.

Gone are the rich communities
of grasses and other small plants,

that once lived here together
with hundreds different kinds

of insects and small creatures.

Now over thousands of square miles,
all other plants and all otherlarge animals,

except human beings,
are rigorously excluded.

Intruders are poisoned or shot.

So mankind has introduced
to the earth a completely new type

of environment, a monoculture,
one which contains,

to all intents and purposes,
just one species.

And this is another of
mankind's virtual monocultures.

The species that proliferates here
and congregates of its own accord

into dense swarms numbering
millions is Homo sapiens himself.

The tallest building he's constructed
so far is in Chicago, the Sears Tower.

It stands 1,454 feet high.

12,000 people daily come to work
in it, and they live in an

artificial microclimate in which
the temperature and humidity

are controlled by computers.

The whole structure is built of
artificial man-made materials,

a framework of steel,
with black-skinned aluminium

and bronze-faced glare-reducing
glass forming a shell around it.

In such an environment as this,
you might suppose that animals

and plants could have no place.

But not so.

Many human beings, it seems,
don't wish to live totally out of

contact with other living species.

Once again, people have moulded
their animals to match their particular

whim and fancy, altering their size,
their proportions, their fur.

Even their smells.

Dogs first associated with man
when he was a nomadic hunter,

accepting him as a leader in a chase,
helping him to track and pull down

his quarry, and taking a
share in the spoils, but now

that man no longer hunts, his
dogs must play a very different role.

Cats are not, in the wild,
social animals like dog

but solitary hunters with
strong territorial instincts.

They probably decided of their own
accord to move into peoples houses

and hunt rats and mice, and
people accepted them because they

peformed this useful service,
and because they're so endearing,

but to this day they have remained
independent operators,

aloof and haughty, even when
people have bred them to exaggerate

the most cuddlesome of
their characteristics.

A few other living organisms have
discovered that the city suits them.

The well-drained sterility of a lava
flow is not unlike that of a city street,

and back in the 18th century a botanist
found a yellow ragwort growing

on the slopes of Mount Etna.

He took it back to Oxford,
where it was cultivated in the

botanic gardens.

60 years later, the ragwort was
noticed growing on the stones

of college walls, but for quite
a time it spread no further.

Then, in the 19th century,
railways were built across Britain.

The stone rubble on which the
tracks were laid was exactly what

the ragwort liked.

And it spread along the railways
to appear in all the cities along

the main lines,
where it still flourishes today.

A few wild animals have also found
what they need in the apparently

hostile wildernesses
that man has created.

The sea otter swims happily in the
waters of California's harbours.

Prairie dogs, driven off the prairies
by ranchers, and farmers,

find new homes in
urban playgrounds.

English foxes have discovered a
rich source of food in city litter bins

and doze on suburban roofs.

And in the south-west of the
United States, acorn woodpeckers

continue to store their acorns in
the trunks of fir trees, even when

they've been turned
into telegraph poles.

Ospreys habitually build their
nests in the very tops of trees,

and telegraph poles also give them
the kind of isolation they need.

Church towers, to kestrels, are just
as good nesting sites as rocky crags.

While Kittiwakes apparently regard
modern buildings as little more than

particularly regular sea cliff.

Swallows learned to tolerate man
for the sake of the nest sites

beneath his eaves, and now
few nest anywhere else.

But not all people's urban
companions are so welcome.

There are still plenty of creatures,
mammals and insects,

that manage toclaim a share
of mankind's food.

Many insects eat cellulose,
and find it in abundance in wood

and in the paper with which
people surround themselves.

Grubs chew the sheep hair
with which clothes are made.

And this whole community of
insects is in turn preyed upon

by other unwelcome creatures:
Spiders.

So we wage war on the animals
that have come to live with us.

Brown rats originated
somewhere in Asia and spread

to Europe some 300 years ago.

Today, rats are found
in every large city in the world.

They will eat almost anything,
tackling meat with as much relish

as grain and vegetables.

They gnaw electric cables,
causing short circuits, and even,

in consequence, fires.

They not only consume huge quantities
of mankind food, but contaminate

much of what they leave,
and they spread disease.

So if we're not to be overrun, we
have to pursue them wherever they go.

We created the city,
and if it's to function properly

and be neither oppressively sterile on
the one hand nor infested with pests,

on the other, we have to manage
the living organisms that live in it,

encouraging some,
exterminating others.

But our influence now spreads far wider
than we often choose to recognise.

Now we're changing the whole of
the globe, and we must equally

accept our responsibilities
of managing that,

but so far we are making
a very poor job of it.

We have to rid our cities of the
vast quantity of rubbish we create.

New York City produces 22,000
tons of refuse every single day.

Half of that is taken by barge
down the Hudson River

and dumped on Staten Island.

The rubbish is laid down in a layer
several feet thick and 200 feet wide.

Every day it advances 100 feet.
When the land is covered,

then another layer is dumped on top.

But this is a very expensive way
of getting rid of our rubbish.

If there are cheaper ways of doing
so, we unhesitating will take them,

telling ourselves if it's out of sight,
it doesn't matter what happens to it,

assuming that somehow
the world is so large

that our poisons will simply
be lost in its immensities.

So we pour our waste chemicals
and detergents into our rivers.

Suds may or may not have
been valuable in a kitchen sink.

In a river they can be lethal,
killing the plants and the fish.

We spill oil into the sea,
in spite of all the precautions,

and set the waves aflame,
and now there are patches of oil

polluting even the remotest
parts of the widest oceans.

And we poison the
very air we breathe.

Fumes belched from our engines
fill the atmosphere of the city.

Steam rising from the cooling towers
of power stations is relatively harmless,

but the gases produced by burning
coal and oil are certainly not.

Our solution to this problem
has been quite simple:

To build chimneys even taller,
so that the gases are blown

farther away from our cities,
but they don't disappear.

They're carried by the prevailing winds
to countries hundreds of miles away.

The lakes of Scandinavia have,
over the past few decades,

become more and more acid

until now fish and plants can no
longer survive in many of them.

In Norway alone, there are now
1,800 lakes without fish,

and hundreds more that are dying,

shameful monuments to our
carelessness and lack of concern.

In Germany, 10% of the forests
are seriously damaged,

almost certainly as a consequence of
industrial pollution of the atmosphere

and the collection of the
poisons from it by rain.

But we don't only despoil
the natural world by accident.

We do so quite deliberately.

These islands, just off the coast
of Peru, may seem, on the face of it,

to be the very picture of fertility
and ecological success

They're the home of a
great variety of seabirds:

Cormorants and pelicans,
boobies, terns and gulls.

But 30 years ago, another bird
was also living here:

These, a kind of cormorant
called the guanay.

When these pictures
were taken in the 1950s,

five and a half million of them were
nesting on just one of these islands.

The guanay lives exclusively
on anchovies and, oddly,

excretes an unusually high proportion
of the fish it eats as droppings or guano.

No rain ever falls here, so the
guano wasn't washed away

but accumulated on the rocks.

A 100 years ago the world realised
that this was a fertiliser

of unparalleled richnes

It was collected and sold for
such high prices that the guanay

cormorant became known as the
most valuable bird in the world.

But then, in the 1950s, chemical
fertilisers were developed in Europe,

the price of guano began to drop
and the people here started to harvest

not the guanay's cormorant
droppings, but its food: Anchovies.

In one year, 14 million tons of anchovies
were taken out of these waters.

They were sold not to feed people
but cattle, and chickens and pets.

The fishing was so intense that the
anchovies were almost wiped out.

That in turn brought about the collapse
of the guanay cormorants' population.

And now for every 50 cormorants
that used to live here,

you're lucky if you find one.

And these walls that would be filled
with guano to the top inside two years,

now seldom accumulate
more than an inch or so.

But the cormorants shed their guano
not only on the land but in the sea.

Indeed, for every drop they put
on land, they shed 20 into the sea.

And there it fertilises water
just as it fertilises the land,

promoting the growth of floating plants,
plankton, the food of the anchovy.

So it's not only that if you get less
anchovies you get less cormorants,

and if you get less cormorants,
you get less anchovies.

Anchovies are food not just for
cormorants but for sea fish

like tuna and sea bass.

So, with that one rash act
of overfishing 30 years ago,

Peru has lost anchovies,

cormorants, guano and sea fish.

It's a major blow to
the nation's economy.

Nor does it seem that we are
learning from our mistakes.

We're in the process of making
similar catastrophic misjudgements,

and on an even greater scale,
in the world's tropical rainforests.

This, the richest of all living
communities, has been

of enormous value to us.

It's provided industry with rubber,
craftsmen with hardwoods,

and our larders with bananas, nuts,
chewing gum and chocolate.

Nearly a quarter of our drugs are based
on animals and plants that live here.

And still we have only investigated
in detail the biochemistry of less

than 1% of the rain forests plants.

And here, too, live some of the most
beautiful and bizarre creatures

to be found anywhere on the planet.

These animals are the product
of millions of years of evolution

here, in these forests.

They can't live anywhere else. The
numbers of each different species

within a given area remains
remarkably stable, but over the past

few centuries one species of animal
outside the forest has suddenly

started to increase in numbers
in a way that is without parallel.

In South-East Asia,
as in South America and Africa,

thousands of extra people every year

are seeking land on which to grow food
for themselves and their children.

They take it from the forest.
The labour is huge.

After the trees have been felled and
burnt, the people sow their crops,

in this case, hill ruts.

After a month, it's as tall as this,
and in only five months it will be

ready to be harvested,

and it will have been sustained by
this, the ash from the burnt forest.

But there are only enough nutrient
in this to sustain one crop.

So next year the people plant not
rice but this, cassava or tapioca,

as it's called here.

This is a different kind of crop,
a root crop, which gets its nutrients

from deeper in the soil, but even
this can only produce for one year.

After that, the seeds from the wild forest
will come in and new plants will grow,

producing a landscape like that.

But they will have to grow for eight to
ten years before they are big enough

to be felled and produce enough ash
and nutrients to refertilise the soil

and allow the people
to take a second crop.

And the true forest, with all its
original richnes of animals and plants,

will never be restored.

It's not only the local people
who cut down the forest.

So, indirectly, do the people
of the developed world.

The huge trees are
in perpetual demand

to provide timber for furniture,
for constructing buildings and crates

and above all for the paper for which
the world has an unquenchable appetite.

So a tree that took 200 years to
grow is now cut down by a

chainsaw in five minutes.

The gigantic trunks, which once
could only be shifted by elephants

and only be extracted from forests
growing on relatively flat country,

are now handled with terrifying
ease by modern machinery.

Sometimes only the biggest trees are
taken, leaving smaller ones standing,

but the damage is such that the
forest is largely beyond recovery.

As the international price of timber
increases, so more and more of the

tropical forest is destroyed.

In South-East Asia, it's been reduced
to about a third of its original size,

and, in the world at large,
an area the size of Switzerland

is being destroyed every year.

But this may be a ray of hope.

This is the fastest-growing tree in
the world. It' called Albizia

and comes from eastern Indonesia,
and can be planted immediately

after the felling of the jungle.

In just one year it can grow
to 10 or 11 metres tall, 35 feet.

This one is some two years old
and in only another six years

it will be ready for logging.

Albizia will grow well on the relatively
poor land that once supported

rainforest, and many sawmills
actually prefer small, easily handled

logs of uniform size.

So if it were possible to produce
this kind of timber on a really

large scale, it might no longer
be necessary to continue

the extremely expensive and
appallingly destructive business

of felling the wild trees.

And were that to happen,
then, in some parts of the world,

away from the coasts, away from
the rivers, in remote and

mountainous country, the
tropical rainforest might still survive.

The great rivers of the world can
also yield riche to mankind,

not simply food but power.

We've known for almost a century
how to turn the force of

tumbling water into electric power.

We've made mistakes in doing so.
The dams we've built have filled up

with silt and become useless within
decades, and fields downriver,

robbed of their annual supply of
fertilising mud, have turned to desert.

But we're getting better at it,
and we're doing it on a greater scale.

This dam, at Itaipu between
Paraguay and Brazil,

will harness the power of one of South
America's greatest rivers, the Parana.

I am walking across what was
once the bed of that river.

And above me rises the
biggest dam ever built by man.

It contains enough concrete to
construct a whole city to house

four million people.

It will make a lake which will stretch
upstream for 140 kilometres.

And the power it will produce will be
enough to supply the whole of Paraguay

and the great cities of southern Brazil:
Sao Paolo and Rio de Janeiro.

And the astonishing thing is that it will
have taken only seven years to build.

There will, of course,
be a heavy price to pay.

44,000 people will have to be moved
and their villages and fields submerged,

fields that produce 200,000
tons of food a year,

and that will create further
demands on the rainforest.

Even so, this major reshaping
of the surface of the earth

is likely to be one of the less
damaging of those that mankind

has inflicted on the planet.

A million trees of 50 different
forset species will be planted

around the lake to prevent
silt from washing down into it.

The water will slowly clear and
develop a population of fish.

And the turbines in the dam, will
produce power without poisoning

the atmosphere or leaving
behind radioactive waste.

They will not deplete the earth's
irreplaceable reserves of fossil fuel,

and the dam will continue to
produce electricity, it's estimated,

for the next 300 years.

The scale of this immense
construction is awe-inspiring

evidence of the power that we
now have in our hands

with which to transform
the face of the earth.

When, in prehistoric times,
these stones were first put up

to build this temple in the west
of England at Avebury, they too

must have been an astonishment
to the local people, an amazing

demonstration of how clever, how
powerful, human beings had become.

And yet that was less than 5,000
years ago, a mere moment

in the history of life.

And in the brief period since then,
men have gone on to learn how to

build dams like Itaipu, how to
mould animals and plants to suit

their needs or their fancies,
how to transform whole landscapes.

Immensely powerful
though we are today,

it's equally clear that we're going to
be even more powerful tomorrow.

And what's more, there will be
greater compulsionto use our power

as the number of human beings
on earth increases still further.

Clearly, we could devastate the world.

If we're not to do so,
we must have a plan.

And just such a plan has been
formulated by environmental scientists.

They called it the
World Conservation Strategy

and it rests on three very
simple propositions.

One: That we shouldn't so exploit
natural resources that we destroy them.

Common sense, you might think.
And yet, look what we've done to the

European herring,
the South American anchovy,

and are still doing to the whales.

Two: That we shouldn't interfere
with the basic processes of the earth

on which all life depends,
in the sky, on the green surface

of the earth and in the sea.

And yet we go on pouring poisons
into the sky, cutting down

the tropical rainforest, dumping
our rubbish into the oceans.

And third, that we should
preserve the diversity of life.

That's not just because we depend
upon it for our food, though we do,

nor because we still know so
little about it that we won't know what

we are losing, though that is the
case as well, but it is surely that we

have no moral right to destroy
other living organisms

with which we share the earth.

As far as we know,
the earth is the only place

in the universe where there is life.

Its continued survival
now rests in our hands.

Repair and Synchronization by
Easy Subtitles Synchronizer 1.0.0.0