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In the vastness of the Pacific,
there's a place unlike any other.
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Enchanted volcanic islands
that are home to a remarkable
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collection of animals and plants.
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Here, evolution is proceeding with
spectacular speed.
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Black lizards that swim in the ocean
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and spit salt from their noses.
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Penguins, thousands
of miles from Antarctica.
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And an abundance of unique plants.
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Some animals are tiny,
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and some have only just
been discovered.
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This is a place of wonders.
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Galapagos.
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Islands born of fire,
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with inhabitants that have
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transformed our understanding
of the whole of life on Earth.
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In a lifetime spent making
natural history films,
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I've been to many wonderful places
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but none more extraordinary than
here, the Galapagos Islands.
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These have been called nature's
greatest experiment, for here,
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life has evolved in isolation and
produced some extraordinary results.
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The extraordinary
creatures of Galapagos astounded
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Charles Darwin when he first came
here 200 years ago.
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They led him
to formulate his revelatory
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theory of evolution by natural
selection.
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And now, 200 years later, there
are still mysteries to be solved
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and new discoveries to be made.
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Teams of scientists are
investigating unexplored regions of
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the remote islands and discovering
hitherto unknown animals.
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On the peaks of its volcanoes,
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inside networks of immense
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tunnels within the lava flows
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and in its crystal clear waters.
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Among a population of giants,
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and in the magical world that is
revealed by the microscope.
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New technologies are enabling
scientists to investigate
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the workings of evolution
in new ways
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and producing insights that would
have astonished Darwin himself.
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Today, we know a lot
more about these islands.
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The discovery of new species,
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long-term studies
extending over decades,
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have given us new perspectives
not just on this place,
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but on the process
of evolution worldwide.
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The islands lie 600 miles
from the coast of South America
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and straddle the equator.
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There are 16 of them,
and a multitude of small islas,
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all separated from the rest of the
world by the huge expanse of ocean.
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The biggest island is Isabela.
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Lying in the centre of the group, it
has a strange seahorse-like shape.
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That is because it originated as six
separate volcanoes which
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eventually fused into one
great island.
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The most remote of them is Alcedo.
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Its vast crater is four
miles across.
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The huge steep-sided walls,
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still smoking with jets of
volcanic gas and steam,
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make this one of the most
isolated places in the Galapagos.
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And it has become
a sanctuary for one of the islands'
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most spectacular inhabitants.
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Giant tortoises.
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There are thousands of them.
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These are the extraordinary
creatures that gave their name
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to the islands.
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Galapagos in Spanish
means tortoise and here,
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in the pit of the volcano Alcedo,
they've assembled in quite
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some numbers to wallow in the warm
volcanic mud.
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A big one can weigh as much
as a quarter of a ton.
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They live for up to 100 years or
more, which makes them
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amongst the most long-lived of all
vertebrates. And being reptiles,
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they get their energy
by basking in the sun.
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But their bodies are
so big that once they are warmed up,
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they can carry on browsing
for quite a long time.
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The existence of creatures
like these,
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so far from the nearest continent,
poses many questions.
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How, for example,
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did these enormous beasts get to
the islands in the first place?
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But perhaps the most extraordinary
thing about the Galapagos
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tortoises is that they're not
all the same.
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Different islands have
different kinds.
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In their heyday there
were 15 species.
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They seem to have appeared in an
evolutionary blink of the eye
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in this tiny cluster of islands.
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And the tortoises are not
alone in this.
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Almost every animal and plant
in the islands has a similar story.
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00:08:43,827 --> 00:08:48,832
The animal colonists began to
change from the moment they arrived,
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driven to do so by the harsh
volcanic landscape around them.
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There is evidence all around these
islands of their direct
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connection with the furnaces
deep in the Earth's crust.
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But it wasn't
until recently that we
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realised just how close those
connections are, here.
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Underneath the section
of the Earth's crust
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on which Galapagos sits,
there is something extraordinary.
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A gigantic column of super-heated
molten rock rising upwards.
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This hot spot is immense.
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At least 60 miles across.
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It extends downwards for 1800 miles
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and connects the islands to the very
centre of the Earth.
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This image, based on the very
latest seismological data,
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shows the hot
spot from underneath the crust.
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This is the source of the islands'
volcanic activity.
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It began to build the Galapagos
four million years ago.
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A series of islands
emerged from the sea.
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Today, there are 16 of them,
all of which are volcanoes.
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Most are now extinct and the oldest
are crumbling into the sea.
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But the newer islands are still
active and spitting fire.
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The youngest is Fernandina.
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It rose from the sea
just 500,000 years ago.
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And because it's still active,
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the lava fields that cover
it are still unweathered.
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And here, in this desolate,
barren place, we can see how the
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ingredients of a great natural
experiment came together.
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Fate placed these islands
in a unique spot on this planet.
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They lie plumb on the equator,
with its year-long warmth
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and sunshine. But perhaps,
more importantly,
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they also lie at the crossroads
between two competing winds.
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The southeast trade winds blow
up from South America
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and the northeast trades come down
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from the Caribbean and
Central America.
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These two winds are the lifeblood
of the Galapagos.
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They carried the earliest settlers
to the emerging volcanic islands.
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seeds falling from trees in
south and central america
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blown across hundreds
of miles on ocean.
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most lost in sea.
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of those few that reach the islands,
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many fell on steroid baking hot rocks,
but just few who's luckier.
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this extraordinary species
is related to dandelions.
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and its far away to grow where
there is neither soil nor rain.
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a wind blown seed arrives,
and dropes in crevice in the lava.
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Moisture collects and cause it to germinate.
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with its tiny leaves that managed
to collect more moisture.
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and the infinite small quantities of nutrients
that moisture from the skies might contain.
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00:14:20,887 --> 00:14:26,036
some of these leaves may look dead,
and indeed they are.
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the plant is deliberately shutting theme.
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it's ensuring that nothing it produces
is wasted, it's creating its own soil.
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and eventually after 80 to 100 years,
it produced this.
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Scalisia, it seems to grow
straight out of naked rock.
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after such a tiny beginning, this extraordinary
plant has gone from strength to strength.
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today, whole forest of giant dandelion,
blanket the high slopes of the island.
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but some plants use a more direct mode
of transport, than merre gust of wind.
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A bird
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The Albatross is the king of
long distance flight
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00:15:25,722 --> 00:15:28,209
it spends most of its life
on the wing
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But each year it lands somewere,
to breed and rise a chick.
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The appearance of new island in the middle of the
ocean, provide Albatrosss with new nesting site.
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And oftenly huge birds broughts hitchhikers.
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Seeds stock to their feets,
and in their feathers.
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They may even have give hitchhikers, a head start
in life with a nice packet of fertilizer.
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So gradually, small patches of vegetation
begin to appear on the newly emerged islands.
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The seeds of most trees, are too big
to be cared far by birds or the wind.
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But those that habitually grow along the coast,
can use different form of transport.
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This is the seed of Mangrove,
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And when it falls,
it drops in the sea and floats.
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This part of it is green,
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So can make food just like a leaf can, and the seed
can remain made it at sea in life, for a very long time.
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But eventually it may float into an estuary,
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And then water is brackish,
and less buoyant.
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So the heavy end of the seed falls,
and it hangs on the water like this.
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And it's tip, and maybe low tide,
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Trails into the mud, and sticks.
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And the Mangrove has implanted itself.
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This trees are very effective colonists
of newly formed islands.
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The young seedlings
quickly established themselves,
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Their tangled arching roots form a grid, wich slows down
the tidal water searching through them,
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cause in it to drop sediments as mud.
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At low tide, all kinds of creatures
come out to scavenge among the roots,
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And when the tide is high,
other creatures swiming to find a shelter.
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The water's arround the tangle roots,
serves as nest for many species of fish.
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So plants created habitats
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where animals could survive
both in water,
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and out of it.
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00:18:55,362 --> 00:19:00,616
Some of the very first animals
here were spiders.
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There are some 150 different known
species of them
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in the Galapagos today,
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and they travel in a way that
is all their own -
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they balloon.
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00:19:23,766 --> 00:19:28,354
The hatchlings of many species use
specially adapted silk.
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A spiderling climbs to
the tip of a leaf or a twig.
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There, it produces
a thread of silk from the spinnerets
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at the end of its abdomen.
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This 3D electron micrograph
shows that this thread is actually
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two filaments that are stuck
together.
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It's flattened like a blade.
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The slightest wind will catch it.
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Once a gust is strong enough,
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the spiderling lets go with its feet
and is carried up
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00:20:12,966 --> 00:20:14,301
and away.
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Some can float up to an altitude
of several thousand metres.
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And up there in the trade winds
millions of years ago,
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and doubtless many times since,
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some of them made the 600 mile
journey to the Galapagos.
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And spiders were not alone,
floating through the skies.
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Many different forms of life
were brought
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here by the wind from the
South American continent -
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seeds, pollen,
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00:21:07,895 --> 00:21:09,862
viruses, bacteria,
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00:21:09,862 --> 00:21:13,111
algae and insects.
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00:21:14,026 --> 00:21:18,364
Insects, of course, are extremely
important in most ecosystems.
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They pollinate plants
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00:21:20,324 --> 00:21:23,744
and they're food for many other
kinds of animals.
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The species that reached
here are nearly all the smaller
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South American species.
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The bigger ones were too heavy to
make the journey.
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00:21:36,290 --> 00:21:39,669
But one quite large insect did so.
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00:21:43,672 --> 00:21:47,509
And its arrival started a new
phase in the colonisation
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00:21:47,676 --> 00:21:48,928
of the Galapagos.
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It was a beetle.
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00:21:59,320 --> 00:22:02,657
Beetles are nature's great
recyclers.
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00:22:02,782 --> 00:22:07,328
They chew up organic matter
and that helps to create soil.
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00:22:12,829 --> 00:22:17,834
Beetles have sizable bodies
but also large wings.
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That made it possible for one
species to make
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00:22:22,548 --> 00:22:25,759
a wind-assisted passage to
the Galapagos.
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00:22:39,182 --> 00:22:42,852
Once here,
these beetles began to change.
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Later generations had smaller wings.
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00:22:50,276 --> 00:22:54,864
In fact, some Galapagos beetles
lost their wings altogether.
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00:22:58,033 --> 00:23:02,288
Those individuals with smaller wings
were much more likely to stay put.
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00:23:05,165 --> 00:23:09,378
That is because the big wings that
brought the beetles here can
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00:23:09,420 --> 00:23:12,214
equally well carry them off again.
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00:23:17,093 --> 00:23:20,179
Insects and plants that were brought
together in this very
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00:23:20,221 --> 00:23:24,767
arbitrary way now began to
establish new relationships.
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00:23:26,644 --> 00:23:30,148
But one, in particular,
had a very far-reaching effect.
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00:23:31,608 --> 00:23:34,611
Sometimes, surprisingly perhaps,
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00:23:34,652 --> 00:23:41,242
flying insects arrived in the
Galapagos not by air, but by sea.
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Inside this piece of wood,
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there is a nest of a little
carpenter bee, whose ancestors
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00:23:48,416 --> 00:23:51,419
must certainly have arrived
here in that way.
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00:23:55,506 --> 00:24:00,553
This unimpressive little creature
was to be of great help to
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00:24:00,595 --> 00:24:02,764
many of the newly-established
plants.
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00:24:09,855 --> 00:24:13,525
It fed on their nectar
and pollinated them.
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00:24:20,449 --> 00:24:24,495
Carpenter bees are still the main
pollinators on the islands.
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00:24:26,830 --> 00:24:29,750
And the plants have adapted
accordingly.
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00:24:35,464 --> 00:24:37,966
Nearly all the flowers
on the Galapagos
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00:24:38,008 --> 00:24:40,886
are now either white
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00:24:40,928 --> 00:24:42,513
or yellow.
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00:24:46,850 --> 00:24:50,646
Those are the colours
preferred by the carpenter bees,
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00:24:50,687 --> 00:24:53,440
so there's no point in being
anything else.
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00:25:00,405 --> 00:25:02,866
So, land plants flourished.
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00:25:07,789 --> 00:25:12,335
In the sea, there was another factor
that helped the colonists.
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00:25:15,547 --> 00:25:19,676
Amazingly, it came not from the
nearest land, South America
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but from 8,000 miles away,
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00:25:22,428 --> 00:25:25,682
across the Pacific in the
other direction, to the West.
239
00:25:28,725 --> 00:25:31,979
From the tropical
rainforests of New Guinea.
240
00:25:44,434 --> 00:25:48,972
here, there are heavy downpour
of rain every day
241
00:25:58,007 --> 00:26:01,230
The rain washes
nutrients from the forest soil,
242
00:26:02,482 --> 00:26:06,611
down streams into rivers
243
00:26:07,993 --> 00:26:11,580
and finally, into the ocean.
244
00:26:11,583 --> 00:26:13,585
And there, swept up by the currents,
245
00:26:13,627 --> 00:26:18,673
they're carried across the Pacific
to the Galapagos.
246
00:26:18,774 --> 00:26:20,860
They travel not near the surface
247
00:26:20,943 --> 00:26:26,198
but in the depths, by a cold
water current.
248
00:26:26,199 --> 00:26:30,203
It's one of three that
converge on the islands.
249
00:26:30,253 --> 00:26:34,048
Another comes from the Panama Basin,
250
00:26:34,049 --> 00:26:35,050
and yet another
originates near Peru.
251
00:26:39,818 --> 00:26:43,625
This convergence of currents
has had a remarkable
252
00:26:43,639 --> 00:26:46,660
impact on life in the islands.
253
00:26:52,410 --> 00:26:56,674
Scientests, led by marine biologist Stuart Banks,
254
00:26:56,973 --> 00:26:59,881
are today investigating their effect
255
00:27:04,768 --> 00:27:07,938
Well, Galapagos is
unique in the sense that it's
256
00:27:08,147 --> 00:27:11,108
a system in the Tropics, it's lying
right on the equator under
257
00:27:11,115 --> 00:27:13,451
the strong equatorial sun
and these are usually systems
258
00:27:13,459 --> 00:27:17,588
which are considered to be
deserts for productivity.
259
00:27:17,797 --> 00:27:19,090
But Galapagos is different.
260
00:27:19,298 --> 00:27:22,510
There's a unique confluence
of currents and most importantly,
261
00:27:22,552 --> 00:27:25,263
a submarine undercurrent called
the Cromwell current,
262
00:27:25,304 --> 00:27:29,767
and these undercurrents are bringing
micronutrients up into these
263
00:27:29,934 --> 00:27:31,477
sunlit waters.
264
00:27:32,771 --> 00:27:35,941
The Galapagos Islands
in the open Pacific
265
00:27:35,983 --> 00:27:39,111
lie in the path of these
converging currents.
266
00:27:40,904 --> 00:27:42,406
They deflect the cold,
267
00:27:43,447 --> 00:27:48,619
nutrient-laden waters upwards to
mingle with the warm water above.
268
00:27:49,954 --> 00:27:52,873
This mixing creates ideal
conditions for a vast
269
00:27:52,915 --> 00:27:55,501
community of floating
microscopic plants.
270
00:27:57,461 --> 00:27:59,630
Phytoplankton.
271
00:28:05,427 --> 00:28:10,974
Each tiny organism is only a few
microns across
272
00:28:11,016 --> 00:28:13,644
and invisible to the naked eye.
273
00:28:18,816 --> 00:28:25,072
Yet these specks of life underpin
the whole Galapagos ecosystem.
274
00:28:26,908 --> 00:28:30,662
And here the fertilizer
from New Guinea enables them
275
00:28:30,703 --> 00:28:33,748
to hugely increase in both variety
and number.
276
00:28:43,633 --> 00:28:47,637
Scientists have now discovered
that the islands themselves provide
277
00:28:47,679 --> 00:28:51,641
the phytoplankton with something
that is crucial for its growth.
278
00:28:52,934 --> 00:28:56,521
A vital life-enhancing
element -
279
00:28:56,646 --> 00:28:58,022
iron.
280
00:28:59,106 --> 00:29:03,527
Now the undercurrent which hits
the western side of the archipelago,
281
00:29:03,736 --> 00:29:07,865
it's a bit like, imagining, pointing
a hose against the side of a wall.
282
00:29:08,074 --> 00:29:13,537
It forms filaments that physically
spread around the archipelago
283
00:29:13,621 --> 00:29:15,039
and up into the surface.
284
00:29:17,541 --> 00:29:19,626
And it's thought that it's
the abrasion
285
00:29:19,710 --> 00:29:22,046
and the leaching
against the volcanic platform
286
00:29:22,254 --> 00:29:26,884
of the islands which is bringing
iron up into the surface waters.
287
00:29:26,925 --> 00:29:29,053
So, thanks to that unique situation,
288
00:29:29,094 --> 00:29:33,015
you tend to get these huge
phytoplankton blooms and this
289
00:29:33,057 --> 00:29:40,355
is literally millions of these tiny
organisms coming together.
290
00:29:42,194 --> 00:29:46,198
This extraordinary image,
based on satellite data,
291
00:29:46,239 --> 00:29:51,578
shows how blooms of phytoplankton
grow and shrink over the seasons.
292
00:29:59,086 --> 00:30:03,090
These astronomic numbers
of microscopic plants support
293
00:30:03,131 --> 00:30:05,926
another vast community.
294
00:30:07,302 --> 00:30:08,261
Microscopic animals -
295
00:30:12,222 --> 00:30:14,086
zooplankton.
296
00:30:18,645 --> 00:30:20,438
Here, under the waves,
297
00:30:20,647 --> 00:30:26,277
there is a living world of
extraordinary complexity and beauty.
298
00:30:30,698 --> 00:30:34,619
All these tiny creatures
are dependent on the rich
299
00:30:34,744 --> 00:30:37,288
blooms of the phytoplankton.
300
00:30:46,256 --> 00:30:48,383
Some graze on them.
301
00:30:55,890 --> 00:30:59,644
Others graze on the grazers.
302
00:31:00,563 --> 00:31:05,151
Many equally extraordinary creatures
feed on the rich soup.
303
00:31:08,737 --> 00:31:10,739
From small crustaceans
304
00:31:14,659 --> 00:31:17,162
and juvenile jellyfish,
305
00:31:18,579 --> 00:31:21,039
to the young of many fish.
306
00:31:34,305 --> 00:31:38,518
These tiny animals and plants,
in turn, support shoals of larger
307
00:31:38,685 --> 00:31:42,075
fish that swarm in such numbers
and variety that they make
308
00:31:42,110 --> 00:31:48,208
the Galapagos waters among the most
diverse of all marine ecosystems.
309
00:32:03,207 --> 00:32:07,837
Many extraordinary creatures feed
directly on the plankton itself.
310
00:32:09,213 --> 00:32:11,716
Garden eels are quite small,
311
00:32:11,799 --> 00:32:14,844
some 15cm or so long.
312
00:32:28,065 --> 00:32:32,903
But much bigger fish also
feed on the plankton.
313
00:32:41,078 --> 00:32:44,915
They, in turn, are food for hunters.
314
00:32:50,921 --> 00:32:54,508
Among them, the Galapagos shark,
315
00:32:54,591 --> 00:32:58,470
a relative of the tiger shark.
316
00:33:06,271 --> 00:33:09,858
And scalloped hammerhead sharks,
which today congregate
317
00:33:09,900 --> 00:33:15,113
here in numbers that are unequalled
anywhere else in the world.
318
00:33:30,337 --> 00:33:34,049
Huge schools of females are often
surrounded by an outer
319
00:33:34,132 --> 00:33:36,218
ring of patrolling males.
320
00:33:36,801 --> 00:33:41,056
No one is quite sure what's
happening at these times.
321
00:33:42,224 --> 00:33:44,810
It's probably
part of their mating behaviour.
322
00:34:07,665 --> 00:34:12,461
Many coastal species are unique
to these islands.
323
00:34:12,503 --> 00:34:16,090
This is the red-lipped batfish.
324
00:34:21,220 --> 00:34:24,431
Its lower fins have been
modified to enable it to
325
00:34:24,640 --> 00:34:26,809
prowl across the seafloor.
326
00:34:30,874 --> 00:34:33,468
The Galapagos sea robin can also walk
327
00:34:33,553 --> 00:34:37,655
And flashes its bright petrol fins
to frighten away predators
328
00:34:42,113 --> 00:34:46,826
The Trumpetfish has such an elongated
body that it's hard to see
329
00:34:46,927 --> 00:34:49,978
so it's able to sneak up on its pray
330
00:35:02,560 --> 00:35:05,296
And there are giants here too.
331
00:35:09,865 --> 00:35:16,371
This is the Mola Mola, the sunfish.
332
00:35:16,751 --> 00:35:17,168
It's huge,
333
00:35:17,210 --> 00:35:21,548
three metres across and addicted to
lying on its side at the surface.
334
00:35:24,216 --> 00:35:27,511
It eats vast quantities
of jellyfish.
335
00:35:30,013 --> 00:35:36,269
And there are not only fish swimming
in these waters, there are mammals.
336
00:35:36,561 --> 00:35:42,817
Sea lions, whose ancestors
originally came from the coasts of
California.
337
00:35:51,786 --> 00:35:55,206
The Galapagos plankton is
so abundant,
338
00:35:55,289 --> 00:35:59,502
it attracts some of the biggest of
all ocean mammals -
339
00:35:59,710 --> 00:36:01,128
humpback whales.
340
00:36:12,139 --> 00:36:17,019
And rivalling them in size,
the biggest of all fish,
341
00:36:18,521 --> 00:36:21,232
the 20-ton whale shark.
342
00:36:27,028 --> 00:36:31,283
Few parts of the world's oceans can
equal these Galapagos
343
00:36:31,324 --> 00:36:35,579
waters for sheer variety
and abundance of marine life.
344
00:36:40,291 --> 00:36:43,461
And this richness in turn has
attracted a great
345
00:36:43,503 --> 00:36:45,129
variety of sea birds.
346
00:36:52,053 --> 00:36:55,139
Many are long-distance travellers.
347
00:36:59,144 --> 00:37:02,606
The islands have become the best
place in hundreds of square
348
00:37:02,647 --> 00:37:07,527
miles of open ocean for many birds
to rest and to breed.
349
00:37:09,321 --> 00:37:13,325
The Nazca Boobies range
across the whole of the Pacific
350
00:37:13,366 --> 00:37:17,370
but this waved albatross lives
nowhere else but here.
351
00:37:19,748 --> 00:37:25,045
The male frigate bird has a pouch of
scarlet skin hanging from his neck.
352
00:37:26,963 --> 00:37:28,548
During the breeding season,
353
00:37:28,590 --> 00:37:32,219
he inflates it to attract a mate
or see off a rival.
354
00:37:40,060 --> 00:37:41,561
There's also another kind of Booby -
355
00:37:44,981 --> 00:37:46,691
the blue-footed.
356
00:37:54,574 --> 00:37:59,454
His spectacular feet are the key
elements in his courtship
357
00:37:59,538 --> 00:38:02,624
display in which
he tries to persuade his mate
358
00:38:02,707 --> 00:38:06,336
that his really are the bluest
feet around.
359
00:38:32,237 --> 00:38:35,615
Boobies are superb fishermen.
360
00:38:45,250 --> 00:38:50,588
Once they spot a shoal, they fly out
to a height of 25 metres
361
00:38:50,630 --> 00:38:56,636
and then they dive into the water at
speeds of 60 miles per hour or more.
362
00:39:00,432 --> 00:39:05,854
Hitting the water with such force
could kill many birds
363
00:39:05,979 --> 00:39:10,776
but boobies have special air sacs in
their heads that cushion the impact.
364
00:39:39,685 --> 00:39:43,897
Cormorants are coastal birds rather
than ocean travellers
365
00:39:43,944 --> 00:39:47,781
so they can only have arrived
in the Galapagos by accident, having
366
00:39:47,781 --> 00:39:51,035
probably been swept out to
sea by a gale.
367
00:39:51,076 --> 00:39:54,288
But they arrived a very long time
ago
368
00:39:54,329 --> 00:39:55,831
and they stayed.
369
00:39:57,041 --> 00:39:59,084
Like cormorants worldwide,
370
00:39:59,293 --> 00:40:02,171
the Galapagos species is
a superb swimmer.
371
00:40:04,173 --> 00:40:06,759
Its legs are powerful paddles.
372
00:40:16,185 --> 00:40:20,356
And the body itself is
beautifully streamlined.
373
00:40:28,780 --> 00:40:32,450
In effect,
the cormorant flies underwater
374
00:40:33,994 --> 00:40:37,622
and it's certainly able to
out-manoeuvre many a fish.
375
00:40:56,808 --> 00:41:00,270
The Galapagos coast is a great
place for a cormorant.
376
00:41:01,396 --> 00:41:04,482
There are plenty of excellent
nesting sites.
377
00:41:07,569 --> 00:41:10,989
And there are no land predators that
might threaten a bird
378
00:41:11,198 --> 00:41:12,949
sitting in such a vulnerable place.
379
00:41:14,910 --> 00:41:18,205
Its ancestors, when they first
arrived, had wings
380
00:41:18,247 --> 00:41:20,332
like any other cormorant.
381
00:41:23,001 --> 00:41:24,920
But with no need to fly,
382
00:41:24,920 --> 00:41:29,466
its wings over generations became
smaller and smaller.
383
00:41:37,766 --> 00:41:42,229
Now, they are mere stumps with
a few tattered feathers.
384
00:41:44,899 --> 00:41:48,528
So now, the bird can't
fly even if it wanted to.
385
00:41:50,613 --> 00:41:52,365
And since it's flightless,
386
00:41:52,365 --> 00:41:56,327
there is no disadvantage in growing
bigger and the Galapagos
387
00:41:56,369 --> 00:42:00,331
cormorant is now heavier than
any of its flying relatives.
388
00:42:08,005 --> 00:42:12,092
With nothing to hassle it and plenty
of fish in the sea alongside,
389
00:42:12,134 --> 00:42:15,554
the cormorants can now concentrate
on caring for their young.
390
00:42:17,681 --> 00:42:21,977
And in fact, some manage to raise
three broods each season.
391
00:42:32,363 --> 00:42:36,575
But there is another permanent
resident here whose history
392
00:42:36,617 --> 00:42:38,410
is even more remarkable.
393
00:42:42,456 --> 00:42:47,753
Its ancestors lived 5,000 miles
away in the Antarctic.
394
00:42:53,384 --> 00:42:56,137
That creature was a penguin.
395
00:42:58,597 --> 00:43:01,016
Penguins are ocean-going swimmers
396
00:43:01,641 --> 00:43:04,019
but a few thousand years
ago some of them
397
00:43:04,060 --> 00:43:07,893
got caught in the cold waters of the
Humboldt current and were carried
398
00:43:07,964 --> 00:43:13,658
northwards up the coast of South
America and out to the Galapagos.
399
00:43:16,491 --> 00:43:18,076
They could hardly have found
anywhere more
400
00:43:18,118 --> 00:43:19,870
different from their polar home
401
00:43:20,453 --> 00:43:23,665
and in response, they changed.
402
00:43:23,707 --> 00:43:27,127
The emperor penguin that lives
near the South Pole stands over
403
00:43:27,168 --> 00:43:28,294
a metre high.
404
00:43:30,797 --> 00:43:32,799
The Galapagos penguin
405
00:43:33,341 --> 00:43:35,301
is now only half as tall.
406
00:43:46,645 --> 00:43:50,106
And that helps
a lot in the Galapagos.
407
00:43:50,148 --> 00:43:54,361
Small animals lose heat much
faster than big ones.
408
00:44:05,038 --> 00:44:09,042
And the penguins have developed
behavioural tricks as well.
409
00:44:15,382 --> 00:44:18,260
Bare feet are easily sunburnt
410
00:44:18,301 --> 00:44:21,388
so they do their best to keep them
covered.
411
00:44:33,692 --> 00:44:37,737
And some parts of the sea
around the islands are quite cool.
412
00:44:39,364 --> 00:44:43,368
The Humboldt current, flowing
up from the Antarctic and washing
413
00:44:43,409 --> 00:44:47,372
around the western parts of the
archipelago, is still quite chilly.
414
00:44:48,457 --> 00:44:52,961
So, most of the penguins
stay in the channel between the two
415
00:44:53,045 --> 00:44:55,339
western-most islands.
416
00:45:03,806 --> 00:45:08,602
And when things get really hot,
they can still cool off with a swim.
417
00:45:15,525 --> 00:45:17,444
They're quick to detect
the slightest
418
00:45:17,485 --> 00:45:21,865
variation in temperature
and move around to find places where
419
00:45:21,907 --> 00:45:24,367
an eddy might have brought
a pleasing chill.
420
00:45:36,088 --> 00:45:39,383
The arrival of penguins must be
the most unlikely
421
00:45:39,424 --> 00:45:43,887
event in the whole story of the
colonisation of the Galapagos.
422
00:45:46,515 --> 00:45:48,517
But the most important
423
00:45:48,517 --> 00:45:51,479
and influential animals had
yet to appear.
424
00:45:53,355 --> 00:45:54,940
Not birds,
425
00:45:54,982 --> 00:45:56,525
but reptiles.
426
00:45:58,837 --> 00:46:03,884
Many million years ago, somewhere in
South or Central America,
427
00:46:03,925 --> 00:46:06,011
a reptile, an iguana,
428
00:46:06,094 --> 00:46:10,515
was grazing close to the
banks of one of the great rivers.
429
00:46:21,985 --> 00:46:25,364
Perhaps it was
feeding on floating vegetation.
430
00:46:29,827 --> 00:46:33,206
Maybe it fell onto such
a raft from a tree.
431
00:46:38,919 --> 00:46:42,948
Patches of floating
vegetation are still swept
432
00:46:43,031 --> 00:46:47,828
out into the estuaries by flash
floods or tropical storms.
433
00:46:50,289 --> 00:46:51,999
Many are quite big,
434
00:46:52,041 --> 00:46:56,378
and easily buoyant enough to support
a metre-long iguana.
435
00:47:01,050 --> 00:47:06,096
And sometimes, they don't break up
but float out to the open ocean.
436
00:47:08,350 --> 00:47:12,771
Who knows how many thousands
of animals of many kinds have been
437
00:47:12,812 --> 00:47:17,192
lost at sea on rafts like these,
dying from thirst and exposure.
438
00:47:22,905 --> 00:47:25,616
But reptiles are very tough.
439
00:47:30,163 --> 00:47:34,667
They can go without food or
water for days, weeks, even months.
440
00:47:36,169 --> 00:47:40,840
No mammal can survive such
hardships as long as they can.
441
00:47:46,846 --> 00:47:51,225
And, at some point in the history
of the Galapagos, the currents
442
00:47:51,267 --> 00:47:56,522
carried an iguana across 600 miles
of ocean to the islands.
443
00:48:00,109 --> 00:48:03,196
No doubt it happened not once
but several times.
444
00:48:07,366 --> 00:48:11,579
And here, the iguanas settled
and multiplied.
445
00:48:14,373 --> 00:48:16,709
Today, there are thousands of them.
446
00:48:17,793 --> 00:48:22,298
So many, and so widely distributed
throughout the islands,
447
00:48:22,381 --> 00:48:26,385
that they are now one of the
Galapagos' most famous inhabitants.
448
00:48:38,939 --> 00:48:42,568
But these are the most
celebrated of all.
449
00:48:45,738 --> 00:48:48,407
The ones that gave the islands
their name -
450
00:48:48,449 --> 00:48:50,159
giant tortoises.
451
00:48:55,539 --> 00:48:59,710
Tortoises can't swim, but
they can float.
452
00:48:59,752 --> 00:49:04,089
And about three million
years ago, one of them,
453
00:49:04,298 --> 00:49:06,925
a large species from the
South American forests,
454
00:49:07,134 --> 00:49:13,474
was carried away perhaps by
a flash flood and swept out to sea.
455
00:49:13,515 --> 00:49:19,813
After weeks, maybe even months,
they eventually landed on an island
456
00:49:19,855 --> 00:49:25,194
and one of them, perhaps a gravid
female, produced eggs.
457
00:49:25,277 --> 00:49:31,617
As time passed, they spread into
other islands in the archipelago.
458
00:49:31,742 --> 00:49:34,411
Giant tortoises had arrived
459
00:49:34,453 --> 00:49:36,288
in the Galapagos.
460
00:49:45,089 --> 00:49:49,677
With this small selection of animals
and plants in place,
461
00:49:49,843 --> 00:49:52,680
nature's great experiment
gathered pace.
462
00:49:57,351 --> 00:50:00,646
Forged by fire,
463
00:50:00,854 --> 00:50:03,190
fuelled by the ocean,
464
00:50:04,900 --> 00:50:07,152
fanned by the winds
465
00:50:08,653 --> 00:50:13,825
and seeded by a very few
and very different species.
466
00:50:15,581 --> 00:50:19,209
A new community was established
here in the Galapagos,
467
00:50:19,209 --> 00:50:24,673
and one with a very small but very
oddly assorted cast of characters.
468
00:50:24,882 --> 00:50:28,886
There were no amphibians.
Because of their porous skin,
469
00:50:28,927 --> 00:50:31,096
they are poisoned by seawater.
470
00:50:31,180 --> 00:50:35,684
There were no mammals
except for a small short-tailed rat.
471
00:50:35,684 --> 00:50:39,688
Flying insects and seeds of plants
had reached here,
472
00:50:39,813 --> 00:50:41,315
brought by the wind.
473
00:50:41,356 --> 00:50:46,862
But fundamentally, this was
a land of birds which flew here
474
00:50:47,070 --> 00:50:49,364
and reptiles which floated here.
475
00:50:50,696 --> 00:50:53,991
And together, they had to make
a living on this bare,
476
00:50:54,253 --> 00:50:59,258
rocky island that was so crucially
different from the well-watered,
477
00:50:59,300 --> 00:51:02,094
luxuriant forests from which
they had come.
478
00:51:05,430 --> 00:51:09,768
In the next programme,
we will discover how this strange,
479
00:51:09,977 --> 00:51:14,231
oddly assorted cast of characters
learned to colonise even the
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most hostile parts of the Galapagos
and to live with one another.
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And how they changed in the process.
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And we venture even
deeper into the islands,
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into places where even today,
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new species are being discovered.
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