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David.
Attenboroughs.
Galapagos.
s01e01.
1080p.
bluray.
x264
In the vastness of the Pacific,
there's a place unlike any other.
Enchanted volcanic islands
that are home to a remarkable
collection of animals and plants.
Here, evolution is proceeding with
spectacular speed.
Black lizards that swim in the ocean
and spit salt from their noses.
Penguins, thousands
of miles from Antarctica.
And an abundance of unique plants.
Some animals are tiny,
and some have only just
been discovered.
This is a place of wonders.
Galapagos.
Islands born of fire,
with inhabitants that have
transformed our understanding
of the whole of life on Earth.
In a lifetime spent making
natural history films,
I've been to many wonderful places
but none more extraordinary than
here, the Galapagos Islands.
These have been called nature's
greatest experiment, for here,
life has evolved in isolation and
produced some extraordinary results.
The extraordinary
creatures of Galapagos astounded
Charles Darwin when he first came
here 200 years ago.
They led him to formulate his revelatory
theory of evolution by natural
selection.
And now, 200 years later, there
are still mysteries to be solved
and new discoveries to be made.
Teams of scientists are
investigating unexplored regions of
the remote islands and discovering
hitherto unknown animals.
On the peaks of its volcanoes,
inside networks of immense
tunnels within the lava flows
and in its crystal clear waters.
Among a population of giants,
and in the magical world that is
revealed by the microscope.
New technologies are enabling
scientists to investigate
the workings of evolution
in new ways
and producing insights that would
have astonished Darwin himself.
Today, we know a lot
more about these islands.
The discovery of new species,
long-term studies
extending over decades,
have given us new perspectives
not just on this place,
but on the process
of evolution worldwide.
The islands lie 600 miles
from the coast of South America
and straddle the equator.
There are 16 of them,
and a multitude of small islas,
all separated from the rest of the
world by the huge expanse of ocean.
The biggest island is Isabela.
Lying in the centre of the group, it
has a strange seahorse-like shape.
That is because it originated as six
separate volcanoes which
eventually fused into one
great island.
The most remote of them is Alcedo.
Its vast crater is four
miles across.
The huge steep-sided walls,
still smoking with jets of
volcanic gas and steam,
make this one of the most
isolated places in the Galapagos.
And it has become
a sanctuary for one of the islands'
most spectacular inhabitants.
Giant tortoises.
There are thousands of them.
These are the extraordinary creatures
that gave their name to the islands.
Galapagos in Spanish
means tortoise and here,
in the pit of the volcano Alcedo,
they've assembled in quite
some numbers to wallow in the warm
volcanic mud.
A big one can weigh as much
as a quarter of a ton.
They live for up to 100 years or
more, which makes them
amongst the most long-lived of all
vertebrates.
And being reptiles,
they get their energy
by basking in the sun.
But their bodies are
so big that once they are warmed up,
they can carry on browsing
for quite a long time.
The existence of creatures
like these,
so far from the nearest continent,
poses many questions.
How, for example,
did these enormous beasts get to
the islands in the first place?
But perhaps the most extraordinary
thing about the Galapagos
tortoises is that they're not
all the same.
Different islands have
different kinds.
In their heyday there
were 15 species.
They seem to have appeared in an
evolutionary blink of the eye
in this tiny cluster of islands.
And the tortoises are not
alone in this.
Almost every animal and plant
in the islands has a similar story.
The animal colonists began to
change from the moment they arrived,
driven to do so by the harsh
volcanic landscape around them.
There is evidence all around these
islands of their direct
connection with the furnaces
deep in the Earth's crust.
But it wasn't
until recently that we
realised just how close those
connections are, here.
Underneath the section
of the Earth's crust
on which Galapagos sits,
there is something extraordinary.
A gigantic column of super-heated
molten rock rising upwards.
This hot spot is immense.
At least 60 miles across.
It extends downwards for 1800 miles
and connects the islands to the very
centre of the Earth.
This image, based on the very
latest seismological data,
shows the hot
spot from underneath the crust.
This is the source of the islands'
volcanic activity.
It began to build the Galapagos
four million years ago.
A series of islands
emerged from the sea.
Today, there are 16 of them,
all of which are volcanoes.
Most are now extinct and the oldest
are crumbling into the sea.
But the newer islands are still
active and spitting fire.
The youngest is Fernandina.
It rose from the sea
just 500,000 years ago.
And because it's still active,
the lava fields that cover
it are still unweathered.
And here, in this desolate,
barren place, we can see how the
ingredients of a great natural
experiment came together.
Fate placed these islands
in a unique spot on this planet.
They lie plumb on the equator,
with its year-long warmth
and sunshine.
But perhaps,
more importantly,
they also lie at the crossroads
between two competing winds.
The southeast trade winds blow
up from South America
and the northeast trades come down
from the Caribbean and
Central America.
These two winds are the lifeblood
of the Galapagos.
They carried the earliest settlers
to the emerging volcanic islands.
Seeds falling from trees
in South- and Central America,
were blown across
hundreds of miles of ocean.
Most were lost at sea.
Of those few that reached the islands,
many fell on sterile backing hot rocks,
but just a few were luckier.
This extraordinary species
is related to dandelions.
And it's find a way to grow
where there is neither soil nor rain.
A wind blown seed, arrives
and drops in a crevice in the lava.
Moisture collects
and causes it to germinate,
with it's tiny leaves it manages
to collect more moisture
and the infinitesimal of nutrients,
that moisture from the sky's might contain.
Some of these leaves may look dead,
and indeed they are.
The plant is deliberately shedding them.
It's ensuring that nothing it produces
is wasted.
It's creating its own soil.
And eventually after eighty
to hundred years,
it produced this.
Scalesia, which seems to grow
straight out of naked rock.
After such tiny beginnings
this extraordinary plant,
has gone from strength to strength.
Today whole forests of giant dandelions,
blanket the higher slopes of the islands
But some plants used a more
direct mode of transport,
than a mere gust of wind.
A bird.
The albatross is the king
of long distance flight.
It spends most of its life on the wing.
But each year it lands somewhere,
to breed and raise a chick.
The appearance of a new island
in the middle of the ocean,
provided albatrosses
with a new nesting site.
And often this huge birds
brought hitchhiker's.
Seeds stuck to their feet,
and in their feathers
They may even have given their hitchhiker's
a head start in life,
with a nice pakket of fertilizer
So, gradually small patches of vegetation
began to appear
on the newly emerged islands.
The seeds of most trees, are too big
to be carried far by birds or the wind.
But those habitually grow along the coast,
can use a different form of transport
This is a seed of an mangrove,
and when it falls,
it drops into the sea,
and floats.
This part of it is green, so it can
make food just like a leaf can.
And the seed can remain at sea
in life for a very long time.
But eventually it may float into an estuary.
And there the water is brackish
and less buoyant.
So, the heavy end of the seed falls,
and it hangs in the water,
like this.
And his tip maybe at low tide,
trails into the mud
and sticks.
And the mangrove has planted itself
These trees are very effective colonists
of newly formed islands.
The young seedlings
quickly establish themselves.
Their tangled arching roots form a grid
which slows down the tidal water
surging through them,
causing it to drop its sediment,
as mud.
At low tide, all kinds of creatures come out
to scavenge among the roots.
And when the tide is high,
other creatures swim in to find shelter.
The waters around the tangled roots,
serve as nurseries for many species of fish.
So plants created habitats,
where animals could survive
both in water and out of it.
Some of the very first animals
here were spiders.
There are some 150 different known
species of them in the Galapagos today,
and they travel in a way that
is all their own,
they balloon.
The hatchlings of many species use
specially adapted silk.
A spiderling climbs to
the tip of a leaf or a twig.
There, it produces
a thread of silk from the spinnerets
at the end of its abdomen.
This 3D electron micrograph
shows that this thread is actually
two filaments that are stuck
together.
It's flattened like a blade.
The slightest wind will catch it.
Once a gust is strong enough,
the spiderling lets go with its feet
and is carried up
and away.
Some can float up to an altitude
of several thousand metres.
And up there in the trade winds
millions of years ago,
and doubtless many times since,
some of them made the 600 mile
journey to the Galapagos.
And spiders were not alone,
floating through the skies.
Many different forms of life
were brought
here by the wind from the
South American continent.
Seeds, pollen,
viruses, bacteria,
algae and insects.
Insects, of course, are extremely
important in most ecosystems.
They pollinate plants
and they're food for many other
kinds of animals.
The species that reached
here are nearly all the smaller
South American species.
The bigger ones were too heavy to
make the journey.
But one quite large insect did so.
And its arrival started a new
phase in the colonisation
of the Galapagos.
It was a beetle.
Beetles are nature's great
recyclers.
They chew up organic matter
and that helps to create soil.
Beetles have sizable bodies
but also large wings.
That made it possible for one
species to make
a wind-assisted passage to
the Galapagos.
Once here,
these beetles began to change.
Later generations had smaller wings.
In fact, some Galapagos beetles
lost their wings altogether.
Those individuals with smaller wings
were much more likely to stay put.
That is because the big wings that
brought the beetles here can
equally well carry them off again.
Insects and plants that were brought
together in this very
arbitrary way now began to
establish new relationships.
But one, in particular,
had a very far-reaching effect.
Sometimes, surprisingly perhaps,
flying insects arrived in the
Galapagos not by air, but by sea.
Inside this piece of wood,
there is a nest of a little
carpenter bee, whose ancestors
must certainly have arrived
here in that way.
This unimpressive little creature
was to be of great help to
many of the newly-established
plants.
It fed on their nectar
and pollinated them.
Carpenter bees are still the main
pollinators on the islands.
And the plants have adapted
accordingly.
Nearly all the flowers on the Galapagos
are now either white or yellow.
Those are the colours
preferred by the carpenter bees,
so there's no point in being
anything else.
So, land plants flourished.
In the sea, there was another factor
that helped the colonists.
Amazingly, it came not from the
nearest land, South America
but from 8,000 miles away,
across the Pacific in the
other direction, to the West.
From the tropical
rainforests of New Guinea.
Here there are heavy downpours every day.
The rain washes
nutrients from the forest soil,
down streams into rivers
and finally, into the ocean.
And there, swept up by the currents,
they're carried across the Pacific
to the Galapagos.
They travel not near the surface
but in the depths, by a cold
water current.
It's one of three that
converge on the islands.
Another comes from the Panama Basin,
and yet another
originates near Peru.
This convergence of currents
has had a remarkable
impact on life in the islands.
Scientist, led by marine biologist
Stuart Banks,
are today investigating their effect
Well, Galapagos is
unique in the sense that it's
a system in the Tropics, it's lying
right on the equator under
the strong equatorial sun
and these are usually systems
which are considered to be
deserts for productivity.
But Galapagos is different.
There's a unique confluence
of currents and most importantly,
a submarine undercurrent called
the Cromwell current,
and these undercurrents are bringing
micronutrients up into these sunlit waters.
The Galapagos Islands
in the open Pacific
lie in the path of these
converging currents.
They deflect the cold,
nutrient-laden waters upwards to
mingle with the warm water above.
This mixing creates ideal
conditions for a vast
community of floating
microscopic plants.
Phytoplankton.
Each tiny organism is only a few
microns across
and invisible to the naked eye.
Yet these specks of life underpin
the whole Galapagos ecosystem.
And here the fertilizer
from New Guinea enables them
to hugely increase in both variety
and number.
Scientists have now discovered
that the islands themselves provide
the phytoplankton with something
that is crucial for its growth.
A vital life-enhancing element,
iron.
Now the undercurrent which hits
the western side of the archipelago,
it's a bit like, imagining, pointing
a hose against the side of a wall.
It forms filaments that physically
spread around the archipelago
and up into the surface.
And it's thought that it's the abrasion and
the leaching against the volcanic platform
of the islands which is bringing
iron up into the surface waters.
So, thanks to that unique situation,
you tend to get these huge
phytoplankton blooms and this
is literally millions of these tiny
organisms coming together.
This extraordinary image,
based on satellite data,
shows how blooms of phytoplankton
grow and shrink over the seasons.
These astronomic numbers
of microscopic plants support
another vast community.
Microscopic animals,
zooplankton.
Here, under the waves,
there is a living world of
extraordinary complexity and beauty.
All these tiny creatures
are dependent on the rich
blooms of the phytoplankton.
Some graze on them.
Others graze on the grazers.
Many equally extraordinary creatures
feed on the rich soup.
From small crustaceans
and juvenile jellyfish,
to the young of many fish.
These tiny animals and plants,
in turn, support shoals of larger
fish that swarm in such numbers
and variety that they make
the Galapagos waters among the most
diverse of all marine ecosystems.
Many extraordinary creatures feed
directly on the plankton itself.
Garden eels are quite small,
some 15cm or so long.
But much bigger fish also
feed on the plankton.
They, in turn, are food for hunters.
Among them, the Galapagos shark,
a relative of the tiger shark.
And scalloped hammerhead sharks,
which today congregate
here in numbers that are unequalled
anywhere else in the world.
Huge schools of females are often
surrounded by an outer
ring of patrolling males.
No one is quite sure what's
happening at these times.
It's probably
part of their mating behaviour.
Many coastal species are unique
to these islands.
This is the red-lipped batfish.
Its lower fins have been
modified to enable it to
prowl across the seafloor.
The galapagos sea robin can also walk
and flashes its bright pectoral fins
to frighten away predators.
The trumpetfish has such an elongated body,
that it is hard to see,
so it's able to sneak up on its prey.
And there are giants here too.
This is the Mola Mola, the sunfish.
It's huge, three metres across and addicted
to lying on its side at the surface.
It eats vast quantities
of jellyfish.
And there are not only fish swimming
in these waters, there are mammals.
Sea lions, whose ancestors originally
came from the coasts of California.
The Galapagos plankton is
so abundant,
it attracts some of the biggest of
all ocean mammals,
humpback whales.
And rivalling them in size,
the biggest of all fish,
the 20-ton whale shark.
Few parts of the world's oceans can
equal these Galapagos
waters for sheer variety
and abundance of marine life.
And this richness in turn has
attracted a great variety of sea birds.
Many are long-distance travellers.
The islands have become the best
place in hundreds of square
miles of open ocean for many birds
to rest and to breed.
The Nazca *** range
across the whole of the Pacific
but this waved albatross lives
nowhere else but here.
The male frigate bird has a pouch of
scarlet skin hanging from his neck.
During the breeding season,
he inflates it to attract a mate
or see off a rival.
There's also another kind of ***,
the blue-footed.
His spectacular feet are the key
elements in his courtship
display in which
he tries to persuade his mate
that his really are the bluest
feet around.
*** are superb fishermen.
Once they spot a shoal, they fly out
to a height of 25 metres
and then they dive into the water at
speeds of 60 miles per hour or more.
Hitting the water with such force
could kill many birds
but *** have special air sacs in
their heads that cushion the impact.
Cormorants are coastal birds rather
than ocean travellers
so they can only have arrived
in the Galapagos by accident, having
probably been swept out to
sea by a gale.
But they arrived a very long time ago
and they stayed.
Like cormorants worldwide,
the Galapagos species is
a superb swimmer.
Its legs are powerful paddles.
And the body itself is
beautifully streamlined.
In effect,
the cormorant flies underwater
and it's certainly able to
out-manoeuvre many a fish.
The Galapagos coast is a great
place for a cormorant.
There are plenty of excellent
nesting sites.
And there are no land predators that
might threaten a bird
sitting in such a vulnerable place.
Its ancestors, when they first arrived,
had wings like any other cormorant.
But with no need to fly,
its wings over generations
became smaller and smaller.
Now, they are mere stumps with
a few tattered feathers.
So now, the bird can't
fly even if it wanted to.
And since it's flightless,
there is no disadvantage in growing
bigger and the Galapagos
cormorant is now heavier than
any of its flying relatives.
With nothing to hassle it and plenty
of fish in the sea alongside,
the cormorants can now concentrate
on caring for their young.
And in fact, some manage to raise
three broods each season.
But there is another permanent
resident here whose history
is even more remarkable.
Its ancestors lived 5,000 miles
away in the Antarctic.
That creature was a penguin.
Penguins are ocean-going swimmers
but a few thousand years
ago some of them
got caught in the cold waters of the
Humboldt current and were carried
northwards up the coast of South
America and out to the Galapagos.
They could hardly have found anywhere
more different from their polar home,
and in response, they changed.
The emperor penguin that lives near
the South Pole stands over a metre high.
The Galapagos penguin
is now only half as tall.
And that helps
a lot in the Galapagos.
Small animals lose heat much
faster than big ones.
And the penguins have developed
behavioural tricks as well.
Bare feet are easily sunburnt, so
they do their best to keep them covered.
And some parts of the sea
around the islands are quite cool.
The Humboldt current, flowing
up from the Antarctic and washing
around the western parts of the
archipelago, is still quite chilly.
So, most of the penguins
stay in the channel between the two
western-most islands.
And when things get really hot,
they can still cool off with a swim.
They're quick to detect
the slightest
variation in temperature
and move around to find places where
an eddy might have brought
a pleasing chill.
The arrival of penguins must be
the most unlikely
event in the whole story of the
colonisation of the Galapagos.
But the most important
and influential animals had yet to appear.
Not birds,
but reptiles.
Many million years ago, somewhere in
South or Central America,
a reptile, an iguana,
was grazing close to the
banks of one of the great rivers.
Perhaps it was
feeding on floating vegetation.
Maybe it fell onto such
a raft from a tree.
Patches of floating
vegetation are still swept
out into the estuaries by flash
floods or tropical storms.
Many are quite big,
and easily buoyant enough to support
a metre-long iguana.
And sometimes, they don't break up
but float out to the open ocean.
Who knows how many thousands
of animals of many kinds have been
lost at sea on rafts like these,
dying from thirst and exposure.
But reptiles are very tough.
They can go without food or
water for days, weeks, even months.
No mammal can survive such
hardships as long as they can.
And, at some point in the history
of the Galapagos, the currents
carried an iguana across 600 miles
of ocean to the islands.
No doubt it happened not once
but several times.
And here, the iguanas settled
and multiplied.
Today, there are thousands of them.
So many, and so widely distributed
throughout the islands,
that they are now one of the
Galapagos' most famous inhabitants.
But these are the most
celebrated of all.
The ones that gave the islands
their name,
giant tortoises.
Tortoises can't swim, but
they can float.
And about three million
years ago, one of them,
a large species from the
South American forests,
was carried away perhaps by
a flash flood and swept out to sea.
After weeks, maybe even months,
they eventually landed on an island
and one of them, perhaps a gravid
female, produced eggs.
As time passed, they spread into
other islands in the archipelago.
Giant tortoises had arrived
in the Galapagos.
With this small selection of animals
and plants in place,
nature's great experiment
gathered pace.
Forged by fire,
fuelled by the ocean,
fanned by the winds
and seeded by a very few
and very different species.
A new community was established
here in the Galapagos,
and one with a very small but very
oddly assorted cast of characters.
There were no amphibians.
Because of their porous skin,
they are poisoned by seawater.
There were no mammals
except for a small short-tailed rat.
Flying insects and seeds of plants
had reached here, brought by the wind.
But fundamentally, this was
a land of birds which flew here
and reptiles which floated here.
And together, they had to make
a living on this bare,
rocky island that was so crucially
different from the well-watered,
luxuriant forests from which
they had come.
In the next programme,
we will discover how this strange,
oddly assorted cast of characters
learned to colonise even the
most hostile parts of the Galapagos
and to live with one another.
And how they changed in the process.
And we venture even
deeper into the islands,
into places where even today,
new species are being discovered.
Missing parts added and BluRay sync by:
Rie van de Buggy's