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In the vastness of the Pacific,
there's a place unlike any other.
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Enchanted volcanic islands,
make a home to a remarkable
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collection of animals and plants.
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Here evolution is proceeding
at extraordinary speed.
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Galapagos.
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A place of wonders.
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Millions of years ago, the islands
were colonized by a strange cast of characters.
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But to settle in this harsh
unforgiving landscape,
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those new arrivals had to
dramatically adapt their bodies.
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Today, revelatory discoveries are still
being made about them.
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And from their story, we can piece together
how Galapagos came to be
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one of the most diverse
environments on our planets.
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It's perhaps surprising
that the Galapagos
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should have become famous
for its biodiversity.
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For the fact is, that living conditions here
are very tough.
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On the Equator, the heat is intense.
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There's very little water. Much of the land
is covered by bare volcanic rock.
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And yet every species
that lives here
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is descended from an ancestor from the continent,
that have taken on these conditions,
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and won.
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And the way which they did so,
is extraordinary.
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Episode 2
ADAPTATION
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The total land area of 16 islands
and rocky outcrops that make up Galapagos
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is less than half that of Wales.
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And yet for its size,
There are more unique species here
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than anywhere else on earth.
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Why should that be?
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There are clues
hidden within the landscape.
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This crescent-shaped strip of cliff
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rising steeply from the Pacific Ocean,
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is the island of Tortuga.
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And like all the Galapagos islands,
it's a wonderful place to see wildlife.
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Here and there
there's a sea lion.
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And above that, nesting sea birds
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Boobies and Galapagos Gulls.
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But you only really appreciate
the true character of this island
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from the air.
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From here, it's clear that this is the last fragment
of an extinct volcano.
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These curving cliffs are all that remains
of what was once
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a completely circular crater.
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And that is an indication of something very significant,
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about all these islands.
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They change with enormous rapidity.
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The history of these islands
is ver much the same.
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Each is born on the bottom of the sea,
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and rises up through the waters,
to emerge as a volcano.
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This is a tipical Galapagos island,
in its infancy.
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But then after a million years of eruptions,
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volcanic activity ceases.
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Two million years
after its first appearance,
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the island is approaching middle age.
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It has a most climate,
and is covered by forest.
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It begins to sink
under its own weight of ash and lava.
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It's battered by erosion,
and after 4 million years,
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it's near the end of its existence.
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Low-lying and arid,
with little rainfall,
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it's surrounded by beaches of soft sand.
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The waves and rain
continue to take their toll,
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until all that is left
is a craggy outcrop of rock.
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These islands, in geological terms,
are very short lived.
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Today, there are islands in the Galapagos Archipelago
that illustrate every stage in this history.
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The youngest, in the west,
are arid, black, and still breathing fire.
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The oldest, in the east,
have long since ceased to errupt.
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But each island provide its colonists
with a range of habitats.
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And it is the youngest active islands
that pose the greatest problems
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for any animals
that attempt to colonize them.
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In the far west of the archipelago
lies Fernandina.
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This is the youngestof the Galapagos Islands.
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It's forbiddingly desolate,
and inhospitable.
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But one animal
has colonized its shoreline.
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This creature is a specialist
at surviving in this harsh terrain.
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And in adapting to this place,
it has become like no other animal on Earth.
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Behold, the Marine Iguana.
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The ancestors of these iguanas
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almost certainly lived
in the jungles of Central America.
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There, still today,
you can see iguanas
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in the trees overhanging the rivers
nibbling leaves,
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or on rafts of reeds.
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Just occasionally,
some are swept out to sea.
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And the vast majority of course,
die there.
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But just a few, a long time ago,
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were fortunate enough to be swept
by favorable currents out into the ocean,
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and beached up here.
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In their ancestral rainforest habitat,
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iguanas are vegetarians.
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Here, they browse on juicy leaves.
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But the iguanas that first appeared in the
Galapagos, could find no such things.
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So these iguanas, to survive,
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had to eat the only kind of leaf
that was available.
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Seaweed.
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And to get the best of that,
they had to do something even more radical.
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They had to swim.
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They even learned to dive.
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They acquired the ability to hold their breath
for up to an hour,
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so that they could swim down
to a depth of 20 meters.
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Their claws strengthened,
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so they could cling to the rocks
on the seabed.
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And under the water, it found
an endless suply of seaweed.
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But these were just the first steps
in the iguana's extraordinary evolutionary transformation.
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But eating nothing but seaweed,
creates another problem.
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Too much salt.
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The Marine Iguanas dealt with that
in a avery particular way.
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They evolved a special gland,
in their nose.
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They simply sneeze the excess salt
from their blood.
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These changes had to happen very quickly,
in evolutionary terms,
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if the iguanas were to survive.
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But here, conditions sometimes change,
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and then even iguanas
struggle to keep up.
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Every 3 to 7 years, the weather becomes
very extreme, and irregular.
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It's a phenomenon called El-Niņo.
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And it can have a devastating effect
on wildlife.
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Evolutionary biologist Maren Vitousek
has studied the effects of El-Niņo
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on the Galapagos Marine Iguanas.
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She discovered that it decimates their food.
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Marine Iguanas usually eat
red and green algae,
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and that algae dies off completely
during El-Niņo,
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during strong El-Niņos.
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And is replaced by brown algae.
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And Marine Iguanas aren't able to digest
the brown algae,
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so they can eat it, but it sits in their stomach,
basically in a big lump.
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Um, and so you can find iguanas
dead on the beach, of starvation,
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with their stomachs full of this brown algae,
that they're just not able to digest.
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The Marine Iguana is the worst affacted
of all Galapagos animals
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during an El-Niņo.
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As many as 90% of them can perish.
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It's bad news for the iguanas,
but good news for scavengers.
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But now, new research has shown that the iguanas
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have evolved an extraordinary way
to survive the famine.
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They shrink.
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So we saw that the, that the largest animals
were decreasing their body length by as much as 20%.
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And the magintue of that means that it can't be simply
that they're changing their cartilage
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or connected tissue,
or reserving muscles.
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Those things together account
for about 10% of length.
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So instead, 20% of shrinkage really indicates
that it's got to be the skeleton itself that's decreasing in length.
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This amazing ability to reabsorb bone
in times of hardship, is unique to these reptiles.
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It's the most recent discovery in understanding
how the Marine Iguanas manage to survive
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on the coastlines of the youngest Galapagos islands.
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Iguanas are not alone
in making out a living
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on this desolate Fernandina coastline.
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Every animal or plant
has found its own way to survive.
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All are dependant in some way
on the riches of the ocean.
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But away from the coast,
there's barely any water at all.
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There, it's too dry and too hot
for most forms of life.
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But in time, that will change.
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As the island ages, this hostile landscape
will become a little more welcoming.
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It will, one day,
support a rich forest,
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full of new places for animals to live.
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This change is driven
by the volcanic hotspot,
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which brought the island into existence.
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The eruptions continue.
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95% of its final bulk
will accumulate in the next few hundred thousand years.
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By the time the eruptions have ceased,
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it's grown so large,
that it has acquired a new power.
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It has the ability
to create its own weather.
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Humid oceanic winds blowing across the Pacific
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hit this mountain of lava,
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and are so force upwards.
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That cools them, so that
they can no longer hold their load of moisture,
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and it condences
as mist and rain.
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And that allows plants
to thrive.
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Santa Cruz,
in the center of the archipelago,
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is typical of
these middle-aged islands.
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Its slopes are covered
by a mantle of green.
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This might seem to be
a forest of giant trees,
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supporting a rich population
of animals of all kinds.
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But, this being Galapagos,
this forest is different.
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These plants are not true trees.
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Trees tend to have big seeds.
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And few of those made it across the ocean,
to the Galapagos.
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And certainly, none up here
into the highlands.
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But smaller plants have smaller seeds.
Some so small, they can float on the wind.
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And one member of the Dandelion family,
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made it up here.
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And without competition from other trees,
they grew big.
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This, you could say,
is a forest of giant dandelions.
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This very special kind of Dandelion
is called Scalesia.
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It's unique to the Galapagos,
and flourishes on the high slopes
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of Santa Cruz,
and other middle-aged islands.
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It's become the host for a whole community,
that could not exist without it...
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because Scalesia performs a conjuring trick,
that gives life to the rest of the forest.
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There's no ground water
in these thin volcanic soils,
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but the Scalesia tree
is tall enough,
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to collect moisture from the skies,
from clouds and from mist.
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And that is sufficient
to sustain a whole community
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of plants and animals.
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High in the canopy, mist condences
on the spindly criss-cross branches
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of the Scalesia.
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Water trickles down their woody trunks.
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Ferns root themselves in the damp moss
that clings to their bark.
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The moisture creates conditions
where spiders and other small creatures
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can live.
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And on the forest floor,
pools appear.
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Here, dragonflies thrive, and, once again
they belong to a species
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that occurs nowhere else but here.
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But the water's downward journey continues below ground,
to provide for a much stranger form of life.
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Deep under the Scalesia forests
of Santa Cruz,
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there is a hidden network
of mysterious lava tunnels.
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Here, the species-changing power
of Galapagos is still active.
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For scientists like caver
Aaron Addison and biologist Steve Taylor,
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these lava tubes are the Galapagos islands'
new frontier of discovery.
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It is difficult to imagine, or indeed believe that
there are still such untouched areas within a place
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that's so well known as the Galapagos
and so well studied.
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But we do find those areas,
and those areas then lead us to new species
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that are unknown to science because
they haven't been described by anyone else, ever.
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Black volcanic rock still lies only
a few inches down beneath the forest trees
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of Santa Cruz.
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It erupted millions of years ago and flowed down
the sides of the interred volcano,
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in rivers of molten red-hot lava.
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As the surface of the lava cooled,
it solidified and formed
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a rocky skin.
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And when the eruption ceased,
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the still liquid lava continued to flow away,
leaving behind these huge empty caverns.
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And now, a constant trickle of life-giving water
drips down into the winding tunnels.
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Steve Taylor is an expert
on underground life.
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The subterranean world is full of surprises.
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It's just really exciting, because
these animals are pale and eyeless,
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There's no selective pressure
to maintain eyes in a cave so, they're blind.
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And they often have elongated appendages
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so they can either find prey,
or avoid prey.
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This amblypygi,
half scorpion, half spider,
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is a predator and a scavenger.
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It might seem ungainly,
but it's well adapted to this black habitat.
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Eyes are useless down here,
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and it's become almost totally blind.
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Instead, it feels its way through the cave,
with great skill and sensitivity.
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Two of its eight legs are greater elongated,
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and capable of extending
to twice the length of its body.
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This millipede has lost all its color.
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Why spend precious enery creating a pigment,
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in a place where no-one can see it?
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Spiders too haunt the lava tubes.
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And just like the tortoises an iguanas,
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these creatures have evolved
into many different species.
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00:23:22,517 --> 00:23:26,771
There are 90 of them,
all unique to the Galapagos.
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00:23:46,583 --> 00:23:50,003
Such variety in such a small area
seems extraordinary,
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00:23:51,379 --> 00:23:54,716
but on the Galapagos,
it's almost common.
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00:23:58,595 --> 00:24:00,645
The huge number of different habitats
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00:24:00,680 --> 00:24:05,351
has made Santa Cruz
a center of biological diversity.
239
00:24:09,397 --> 00:24:13,610
And as an island ages,
so it develops more habitats.
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00:24:17,864 --> 00:24:20,575
Now, it's entering its old age.
241
00:24:22,368 --> 00:24:24,621
It's no longer growing.
242
00:24:27,957 --> 00:24:31,753
Its sheer mass is to heavy
for the earth's crust to support.
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00:24:32,128 --> 00:24:35,465
It begins to sink under its own weight.
244
00:24:39,636 --> 00:24:43,806
And now, the rainwater that has been falling
on it throughout its middle age,
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00:24:43,841 --> 00:24:47,060
begins to carve away its substance.
246
00:24:48,728 --> 00:24:53,524
So the island becomes smaller,
drier, and flatter.
247
00:24:58,821 --> 00:25:01,783
That is what has happened
to Espaņola.
248
00:25:08,206 --> 00:25:10,959
It's nearing 4 million years old.
249
00:25:15,546 --> 00:25:17,799
Its forests have gone.
250
00:25:20,927 --> 00:25:24,180
But it now has a different range of habitats.
251
00:25:27,600 --> 00:25:32,230
Millions of years of erosion
have created beaches of soft sand.
252
00:25:32,939 --> 00:25:35,733
And they suit some animals very well.
253
00:25:47,745 --> 00:25:50,519
This is a natural bathing beach
254
00:25:50,554 --> 00:25:53,293
for Galapagos sea lions.
255
00:26:02,010 --> 00:26:08,474
They are just one of the very few mammal species
that are unique to the Galapagos.
256
00:26:13,479 --> 00:26:17,775
And the beach of an aging island,
provides them with an excellent nursery.
257
00:26:19,360 --> 00:26:23,531
Here, sea lion pups
can suckle in complete safety.
258
00:26:24,032 --> 00:26:27,702
Though they can be a little irritating.
259
00:26:30,830 --> 00:26:33,958
And in a protected cove,
close by the beach,
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00:26:33,993 --> 00:26:37,503
parent can teach their youngsters
to swim.
261
00:27:03,988 --> 00:27:08,868
After a swimming lesson, the beach
is a perfect place to relax.
262
00:27:34,435 --> 00:27:37,939
Sea lions seem to have an idyllic life.
263
00:27:38,481 --> 00:27:41,067
But there is just one irritant.
264
00:27:42,443 --> 00:27:43,361
Flies.
265
00:27:47,031 --> 00:27:49,624
On the other islands,
with rocky coastlines,
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00:27:49,659 --> 00:27:53,204
sea lions have help
to keep the flies at bay.
267
00:27:54,205 --> 00:27:55,498
Lava Lizards.
268
00:28:04,007 --> 00:28:06,301
But on the sandy beaches of Espaņola,
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00:28:06,336 --> 00:28:09,220
the Lava Lizards are nowhere to be seen.
270
00:28:09,429 --> 00:28:12,807
They prefer the nearby rocks,
which are warmer.
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00:28:18,605 --> 00:28:23,943
Other creatures have also adapted
to live on these 4 million year old beaches.
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00:28:25,528 --> 00:28:29,949
The enormous Waved Albatross,
with its two and a half meter wingspan,
273
00:28:29,984 --> 00:28:34,370
uses the gentle sloping surface
as a runway.
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00:28:39,667 --> 00:28:43,733
As you might expect,
the species of Albatross that lives here
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00:28:43,768 --> 00:28:47,800
is slightly different than those found
in other parts of the world.
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00:28:47,926 --> 00:28:50,929
This wave-like patterns on its neck feathers distinguish it
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00:28:50,970 --> 00:28:54,390
from all other Albatross species.
278
00:29:10,531 --> 00:29:13,701
All Albatrosses spend
most of their lives on the wind,
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00:29:13,736 --> 00:29:16,621
travelling across entire oceans.
280
00:29:23,920 --> 00:29:28,800
Here on Espaņola,
the Waved Albatrosses can nest.
281
00:29:35,473 --> 00:29:40,019
The isolation of the Galapagos, and the protected
soft-shingled beaches of Espaņola
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00:29:40,054 --> 00:29:44,566
make this aging island
an excellent breeding ground for them.
283
00:29:44,649 --> 00:29:47,902
35 thousand settle here each year.
284
00:29:50,488 --> 00:29:52,657
Waved Albatrosses are monogamous.
285
00:29:52,692 --> 00:29:54,534
They mate for life.
286
00:29:56,411 --> 00:30:00,206
But how do you find a new mate,
or recognize your old partner
287
00:30:00,241 --> 00:30:02,584
in such a crowded colony?
288
00:30:05,628 --> 00:30:07,088
You dance.
289
00:30:20,310 --> 00:30:23,146
The whole performance can last for nearly an hour.
290
00:30:25,857 --> 00:30:29,402
And it's repeated several times,
every day.
291
00:30:31,696 --> 00:30:35,033
Sometimes, a potential rival
steps in to try his luck.
292
00:30:36,367 --> 00:30:41,789
The female, in the middle,
dances with both enthusiastic males at the same time.
293
00:30:52,717 --> 00:30:56,471
The reward for the victorious male is great.
294
00:30:59,849 --> 00:31:00,892
A mate...
295
00:31:02,769 --> 00:31:06,940
and an opportunity to pass on his genes.
296
00:31:12,028 --> 00:31:16,074
The many habitats of Espaņola,
and all aging Galapagos islands,
297
00:31:16,109 --> 00:31:21,079
were created by the erosive power of sea,
and weather.
298
00:31:28,378 --> 00:31:33,216
But, erosion can have only one final result...
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00:31:39,472 --> 00:31:41,724
destruction.
300
00:31:44,608 --> 00:31:48,862
A Galapagos island
worned down by the waves and the weather,
301
00:31:48,897 --> 00:31:53,116
eventually reaches the last stage of its existence.
302
00:32:08,256 --> 00:32:11,016
After millions of years sustaining life,
303
00:32:11,051 --> 00:32:16,473
all that remains of it above water
is a rocky, curving cliff.
304
00:32:22,771 --> 00:32:26,108
Like Tortuga.
305
00:32:35,158 --> 00:32:39,746
There are many relic islands like Tortuga in the Galapagos.
306
00:32:51,133 --> 00:32:53,767
Devil's Crown, in the south of the archipelago,
307
00:32:53,802 --> 00:32:58,932
is even closer to disappearing altogether,
below the waves.
308
00:33:00,183 --> 00:33:02,567
But even in its final days,
309
00:33:02,602 --> 00:33:06,440
A Galapagos island provides a habitat for some.
310
00:33:07,983 --> 00:33:11,076
It's rock has been turned by erosion into sediment,
311
00:33:11,111 --> 00:33:17,200
and now that fertilizes the marine life
around its submerged remains.
312
00:33:21,163 --> 00:33:23,296
A ring of coral, 2 meters wide,
313
00:33:23,331 --> 00:33:26,126
encircles its dwindling stump.
314
00:33:29,504 --> 00:33:33,675
So a whole new animal community develops.
315
00:33:38,638 --> 00:33:41,391
Corals are at its center.
316
00:33:43,143 --> 00:33:45,145
Thistle Worms hide inside them,
317
00:33:45,228 --> 00:33:49,399
occasionally emerging to browse on passing morcins.
318
00:33:59,701 --> 00:34:03,288
Fish find safety among their brances,
319
00:34:03,323 --> 00:34:05,582
and some of these species, once again,
320
00:34:05,665 --> 00:34:08,710
are unique to the Galapagos.
321
00:34:22,224 --> 00:34:25,477
The reef teems with life.
322
00:34:55,799 --> 00:35:00,512
So even in the last stages of its life,
a Galapagos island can support
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00:35:00,547 --> 00:35:02,931
a rich animal community.
324
00:35:04,391 --> 00:35:08,645
But remarkably, even this
is not the end of the story.
325
00:35:09,604 --> 00:35:14,484
Because even when an island
has totally disappeared beneath the waves,
326
00:35:14,519 --> 00:35:18,947
it continues to influence life
in the surrounding seas.
327
00:35:21,491 --> 00:35:24,042
The remains of ancience Galapagos islands
328
00:35:24,077 --> 00:35:27,914
stretch for hundreds of miles
across the Pacific seabed.
329
00:35:29,624 --> 00:35:32,544
These were once volcanoes life Fernandina,
330
00:35:32,579 --> 00:35:35,422
vegetated mountains like Santa Cruz,
331
00:35:35,457 --> 00:35:38,341
and low lying nurseries like Espaņola.
332
00:35:41,094 --> 00:35:44,014
Today, those environments are long gone.
333
00:35:44,097 --> 00:35:47,107
But the remnants of the islands,
under the sea,
334
00:35:47,142 --> 00:35:52,564
are still key in the lives of one of the oceans
most magnificent inhabitants.
335
00:35:54,649 --> 00:35:59,029
Up to 12 meters long,
it's the largest fish in the world.
336
00:36:01,740 --> 00:36:03,700
The Whale Shark.
337
00:36:07,370 --> 00:36:10,499
Whale Sharks come to the Galapagos
in large numbers,
338
00:36:10,534 --> 00:36:12,876
at the same time, every year.
339
00:36:14,961 --> 00:36:18,090
But why they do so is a mystery.
340
00:36:25,931 --> 00:36:29,232
Marine biologists, Alex Hearn and
Jonathan Green,
341
00:36:29,267 --> 00:36:32,896
have spent the last 5 years
trying to solve the puzzle.
342
00:36:33,814 --> 00:36:37,150
If you think about how Galapagos is formed
and how the currents work,
343
00:36:37,185 --> 00:36:39,868
The most productive water is actually out west.
344
00:36:39,903 --> 00:36:43,531
So you would've thought that
if Whale Sharks were coming here to feed,
345
00:36:43,566 --> 00:36:47,160
they'd be out in the west of the Archipelago,
and they're not, they're up north.
346
00:36:48,203 --> 00:36:51,331
So why are they coming here?
It's clearly not to feed.
347
00:36:53,542 --> 00:36:57,921
And what we found out recently is
that it's mainly large pregnant females.
348
00:36:58,004 --> 00:36:59,846
Are they coming here to give birth?
349
00:36:59,881 --> 00:37:03,343
This may be the pupping ground
for Whale Sharks.
350
00:37:04,177 --> 00:37:08,682
I'm slightly skeptical.
I think we would've seen juveniles, and we don't.
351
00:37:11,601 --> 00:37:13,235
So, that brings backs the question.
352
00:37:13,270 --> 00:37:18,442
Well if they're not pupping here, and
if they're not feeding here, why are they coming?
353
00:37:31,288 --> 00:37:34,457
To understand the Whale Sharks'
migratory patterns,
354
00:37:34,492 --> 00:37:37,627
Hearn and Green attach satellite tags
355
00:37:37,662 --> 00:37:39,421
to the sharks they encounter.
356
00:37:47,262 --> 00:37:50,390
This enables them to track their movements.
357
00:37:52,642 --> 00:37:57,022
And it's revealing
some extraordinary new facts.
358
00:38:01,401 --> 00:38:07,157
First, the sharks swim open-mouthed through
the rich waters off the west coast of South America.
359
00:38:08,909 --> 00:38:13,330
Then they continue their journey westwards,
to the Galapagos.
360
00:38:14,039 --> 00:38:18,293
But they only spend a few days at a time
in the islands' waters,
361
00:38:18,919 --> 00:38:22,714
before continuing westwards,
out into the open ocean.
362
00:38:31,223 --> 00:38:35,352
Nobody has yet proved
why the Whale Sharks do this,
363
00:38:35,387 --> 00:38:39,481
but Alex Hearn has begun
to formulate some ideas.
364
00:38:40,190 --> 00:38:41,448
I think there are two possibilities.
365
00:38:41,483 --> 00:38:45,112
Firstly, they may be using Galapagos
as a waypoint,
366
00:38:45,147 --> 00:38:47,162
which directs them towards
their pupping grounds.
367
00:38:47,197 --> 00:38:51,750
The other option is that Galapagos
may be providing a service for them along the way,
368
00:38:51,785 --> 00:38:56,998
and that service may be cleaning,
because we do see a lot of cleaning behavior from the reef fish.
369
00:38:57,033 --> 00:38:58,583
Or it may be
a combination of the two.
370
00:38:59,000 --> 00:39:02,302
The long line of submerged Galapagos islands
371
00:39:02,337 --> 00:39:06,591
could play a central role in
the Whale Sharks' extraordinary journey.
372
00:39:08,677 --> 00:39:13,146
It might be that they serve as signposts,
by which the sharks navigate.
373
00:39:13,181 --> 00:39:16,872
If you start looking at where they're going,
especially the tracks that we have,
374
00:39:16,907 --> 00:39:20,564
along those ridges, and then up to the next ridge,
and then back down again,
375
00:39:20,599 --> 00:39:25,659
it certainly seems that they're associating with those ridges,
for one reason or another.
376
00:39:25,694 --> 00:39:31,908
And that could be geomagnetism, or it could also be
something to do with the biology of the water column above those ridges.
377
00:39:31,943 --> 00:39:34,453
But cerrtainly, something is going on.
378
00:39:50,385 --> 00:39:54,222
From their birth to their death,
the islands have acted like
379
00:39:54,257 --> 00:39:56,349
evolutionary pressure cookers.
380
00:39:57,392 --> 00:40:00,187
From the youngest islands like Fernandina,
381
00:40:00,222 --> 00:40:02,571
the middle-aged ones like Santa Cruz,
382
00:40:02,606 --> 00:40:05,817
and the old islands like Espaņola,
383
00:40:08,195 --> 00:40:12,699
they're extremely varied,
with contrasted conditions.
384
00:40:18,246 --> 00:40:24,711
Deserts, rainforests, and polar waters,
crowded together in a very small area.
385
00:40:52,656 --> 00:40:59,121
These huge variations have created
a wide range of opportunities for the few animals
386
00:40:59,156 --> 00:41:01,206
that have managed to reach here.
387
00:41:11,174 --> 00:41:14,094
As they colonized...
388
00:41:17,013 --> 00:41:19,433
so they adapted.
389
00:41:20,475 --> 00:41:22,769
And consequently, flourished.
390
00:41:30,610 --> 00:41:35,782
That explains many of the oddities
of the inhabitants of these islands.
391
00:41:44,458 --> 00:41:48,503
Including that most fundamental phenomenon of all,
392
00:41:48,538 --> 00:41:52,883
the appearance of new species.
393
00:41:56,470 --> 00:42:00,307
The giant tortoise is
the very emblem of the Galapagos,
394
00:42:00,342 --> 00:42:04,144
and in their hayday, there were
hundreds of thousands of them.
395
00:42:04,179 --> 00:42:07,272
Not only that, there were
15 different species
396
00:42:07,307 --> 00:42:09,775
each in its own locality.
397
00:42:10,233 --> 00:42:15,113
But why should there be so many species
within such a compositively restricted area?
398
00:42:15,614 --> 00:42:19,785
In the next program, we'll look
at the deep geological forces,
399
00:42:19,820 --> 00:42:22,913
that can make a single species
produce many
400
00:42:22,948 --> 00:42:26,875
and turn the Galapagos
into this wonderland.