Wildest Islands (2012–…): Season 1, Episode 3 - Galapagos: Darwin's Eden - full transcript
The Galapagos archipelago, way off Chile's coast, is named after the saddle shape of it iconic, century-living giant turtle species. Considered hellish by its Spanish discovers, it became a paradisaic nature reserve. Its uniquely odd land - and aquatic wildlife, evolving at record speed due to the fast emergence and transformation of volcanic islands at a tectonic crack where three major ocean currents meet, greatly inspired Charles Darwin's evolutionary theories.
Flowing lava.
Sun scarred landscapes.
And few signs of life
that early explorers
to name the Galapagos Islands
hell on earth.
But beyond these parched beginnings,
this volcanic archipelago
is now our planet's greatest Eden.
A wilderness so pristine and rich in life
it allowed one man's studies to alter
our entire view of the natural world.
Older islands fade away
while new ones emerge
from beneath the sea.
The Galapagos continue to evolve
and continues to be
nature's greatest evolutionary arboratory.
The Galapagos Islands rank among
the most spectacular
scientific discoveries in history.
Situated 1,000 km west of Ecuador
in South America,
the archipelago contains 13 main islands
and a hundred or so
smaller rocks and reefs.
Some are so desolate and barren,
they reveal few signs of life.
Others are rich haven providing a home
to bizarre and unique creatures.
Human influence has been so limited
across the islands,
it allowed one man to study and rethink
the laws of nature.
In 1835, 26 year old Charles Darwin
sailed to the Galapagos Islands
in HMS Beagle.
The ship's mission was
to survey the coast of South America.
Darwin was the ship's botanist.
Thirty years later,
Darwin published his theory of evolution,
one of the most revolutionary ideas
science has ever known.
It was the islands' small land birds
like finches and mockingbirds
that proved key to Charles Darwin's theory.
Each of the 13 species of finch
has a different beak
for a different purpose.
Some are thick and heavy
for crushing seeds.
Others long and pointed
for accessing pollen in flowers.
They all descended from a common ancestor
that arrived on the islands
millions of years ago.
The finches established themselves
and began to determine territories.
With no competition from other birds,
they diversified.
They developed unique adaptations
for each type of habitat.
New species were born.
Darwin explained that natural selection
was the driving force
behind this rapid evolution.
Following the publication of his theory,
these ordinary looking small birds
have been given a new collective name,
Darwin's finches.
The Galapagos Islands
were named after their giant tortoises.
The old Spanish word, galapago,
meant saddle.
A term early explorers
used for the tortoises
due to the shape of their shells.
The Galapagos tortoise
is the largest in the world.
Some reach a meter and a half in length
and can weigh 250 kg.
These slow moving reptiles
lead an uncomplicated life.
Most days are spent
grazing on grass and leaves
in between basking in the sun.
Like all reptiles,
giant tortoises rely on the sun
to warm their bodies
and become active.
However, the midday sun
can be too much to bear
even for cold blooded creatures.
Fortunately, the islands' lakes don't just
provide a valuable source of drinking water.
Bathing in the muddy shallows
is the perfect way to cool down.
A slow metabolism
and large internal stores of water
allow the tortoises to survive
for up to a year
without eating or drinking.
Inactivity also helps.
They sleep for around 16 hours a day.
These giants can live for over 150 years.
Darwin noted a variation
in the shape of the shell
of tortoises from different islands.
This became additional evidence
for developing his theory of evolution.
Galapagos creatures evolve
and adapt to their habitat.
And their island homes
are ever changing too.
The youngest islands furthest west
are still forming.
A static volcanic hot spot
1,000 km beneath the sea
continually forces lava to the surface.
These newly formed masses eventually cool
and then drag southeast
at a rate of 5 cm a year
from shifting oceanic plates.
On their 200 km journey east,
they witness many changes.
Ultimately all Galapagos islands
face the same fate.
Disappearing beneath the ocean
without a trace.
Darwin described how eager he was
to witness an active volcano.
Although there were no eruptions
during his visit,
his geological observations
altered many volcanic theories.
The newest and most westernly
Galapagos island is Fernandina.
Still situated
directly over the oceanic hot spot,
this volcanic mass has erupted 24 times
in the past 200 years.
It's one of the youngest
and most active volcanoes on earth.
Fernandina's peak
stretches 1,500 meters high
and its crater spans 6-1/2 km.
The island's lava clad rocky shores
and black sand beaches
seem the most forbidding
of all the Galapagos Islands.
Yet life has started to take hold.
Pioneer plants such as these lava cactus
are often first to take root.
Their seeds carry from older islands
by bird droppings
or directly by the wind.
But there is one creature
that has colonized the entire archipelago
and its mode of travel relies on the sea.
Marine iguanas are excellent swimmers.
They can reach over a meter in length
and weigh as much as 9 kg.
Over 250,000 of these swimming dragons
inhabit the Galapagos.
They are the world's only species
that marine lizard.
It's thought that millions of years ago,
land dwelling iguanas from South America
drifted out to sea on floating debris.
They eventually landed on the islands.
Isolated from the main land,
a new iguana evolved
and adapted to life at sea.
Like all iguanas,
this species is vegetarian.
Yet Fernandina offers very little
in the way of visible food.
But this species rarely goes hungry.
Being cold blooded, iguanas need to raise
their body temperatures
to approximately 36° C
in order to function.
After an hour or so
basking in the equatorial sun,
this iguana launches its feeding mission.
A flattened tail allows it to dive down
to depths of 12 meters
to access tufts of red and green algae
on the submerged rocks.
A shortened blunt snout allows it
to crop the plant close to its face.
This algae is the marine iguana's
exclusive diet.
Fernandina's currents
are surprisingly cold.
The iguana's body temperature
can plummet 10° on an extended dive.
After just 10 minutes,
its muscles begin seizing up.
Getting back to dry land in time
is critical to survival.
Long, sharp, recurved claws
enable the lizard
to hold fast to the lava in heavy seas
or when submerged.
Along with the algae, marine iguanas ingest
a great deal of salt.
Specially adapted glands above each eye
are connected by ducts to each nostril.
The excess salt is sneezed out.
Only the larger marine iguanas
risk running
the gauntlet of the islands' chilling seas.
Smaller individuals choose a safer option
and graze only at low tide on dry land.
Fernandina is less than
half a million years old
and offers little sanctuary
to land living creatures.
But drifting 75 km further east
are islands more than twice its age
and different worlds entirely.
Isabella is the largest
of all the Galapagos Islands.
Consisting of six overlapping volcanoes,
its over 100 km long.
It makes up half of the total land area
of the Galapagos.
The volcanic hot spot
still simmers beneath Isabella's seas.
While above the surface, a creature
key to Darwin's evolutionary theory
prepares to dive the deep.
This cormorant is unique to the Galapagos.
Its wings are disproportionately small
to the size of its body.
They're about one third the size required
for it to take to the air.
This species has evolved to be flightless.
Its legs are much stronger
than those of other cormorants.
Enlarged feet propel
its stream lined meter long body
in search of octopus and small fish.
Darwin noted that the flightless cormorant
could not have swum
from the mainland to the islands.
It never ventures
further than 100 meters from the shore.
It diverged from its flighted cousins
and eventually became marooned
on the islands.
An abundance of food
and an absence of predators
has allowed this mutant bird to flourish.
Its the largest of all cormorant species.
Seaweed makes the perfect nest material
on top of jagged lava rock.
Both parents play a part
in raising their young.
Although it can no longer fly,
the bird still holds its wings up to dry.
It's a memory left over
from ancestral habits.
Further inland, saltwater lagoons
provide the perfect refuge
to one of the world's most iconic birds.
Greater flamingos
usually live in large colonies
of up to 10,000.
The Galapagos plays home
to the world's smallest population
numbering less than 600.
Most of their day is spent feeding.
The shallow water enables them
to turn their heads upside down
and sweep from side to side.
They filter up to 20 mouthfuls a second,
separating brine shrimp
and small crustaceans
from the mud and silt.
The consumption of shrimp provides
the pink pigment of their feathers.
The small population size of the Galapagos
has resulted in changes
to their breeding behavior.
Flamingo populations elsewhere
rely on very large groups of birds
for breeding to occur.
Galapagos flamingos can breed
with just a few pairs present.
It's the start of the nesting season,
and their unique courtship ritual begins.
Males and females mate for life.
These coordinated displays
are key to reaffirming their bonds.
Wing salutes,
turning their heads in unison,
and twist preening
are important courtship signals.
The Galapagos flamingos
originally flew in from the Caribbean.
Whereas one mammal swam over 5,000 km
to set up home here.
Galapagos sea lions
arrived from California.
They're slightly smaller
than their North American relatives.
But at over 2 meters in length
and weighing as much as 250 kg,
they are by far the largest mammals
of the entire Galapagos Islands.
They're most likely
one of the first animals Darwin encountered
when he came ashore around 180 years ago.
Sea lions are well adapted
to a semi-aquatic lifestyle.
Along with a streamlined body,
they can control their hind flippers
independently.
This makes them far more agile
than true seals.
Females give birth to just one pup
and remain with them on shore
for the first week.
After this, they go off on foraging trips
that can last up to three days.
Pups left behind gather in nurseries
where they socialize and play.
One female remains behind to keep watch.
When returning from a trip,
females alert their pups
with distinctive calls.
These reunions initially
rely on the mothers.
But once they're older,
the youngsters call out too.
Pups are suckled for up to 12 months,
three times longer
than many other seal species.
Adult male sea lions
play no role in raising their young.
A dominant bull
also known as a beach master
spends the majority of his day patrolling
the territory occupied by his harem.
This particular male
has some unwanted company.
The intruder is defeated
for now at least.
Keeping other males at bay
is exhausting work.
Some beach masters succeed
for just a few days.
Even the toughest only manage to protect
their patch for a maximum of three months.
With the storm over, everyone can relax.
However, another predator
prepares to move in.
It's been patiently waiting
for the sea lions to drop their guard.
Lava lizards are carnivores.
This one has singled out its prey.
Flies are a constant irritation
to the sea lions
so they welcome
this free grooming service.
These Galapagos reptiles play an important
role in controlling insect populations.
Male lava lizards can live up to 10 years
and may have three or more mates
in their harem.
This male approaches one of his conquests.
He bobs his head up and down
to signal his intentions.
This female isn't ready or willing to mate.
Turning her back and raising her tail
lets the male know
he's been rejected.
The Galapagos Islands sit on the equator
except the climate here
isn't typically tropical.
The reason lies
within the surrounding seas.
Three major ocean currents
collide at the very point
where the Galapagos Islands lie.
The warm Panama Current from the north
supports the island's
more tropical marine life.
The icy Humboldt Current from the south
brings nutrient rich
waters from Antarctica.
And from the west,
the deep water Cromwell Current
rises to the surface
upon hitting the Galapagos shelf.
Elsewhere, the temperature at sea level
is usually warmer than at higher altitudes.
But here, the opposite is true.
The cold waters from the south and west
cool the air above them.
Colder waters are rich in green algae,
which supports
a diverse and vibrant food chain.
Over 500 species of fish
rely on these plankton rich seas.
Large schools of hammerhead sharks
patrol the islands' waters all year round.
This unusual looking predator
can reach over 4 meters in length.
Its eyes are a meter apart.
Darwin found the Galapagos
to be home to many unusual creatures.
But none more unexpected than this.
Galapagos penguins
descended from ancestors in the Antarctic,
10,000 km further south.
They are the only kind
living in the northern hemisphere.
It's thought they arrived
during the last Ice Age
after being swept north
by the Humboldt Current.
They later became stranded here
after the earth warmed.
The islands furthest west
still suffer the effects
of the Pacific Ocean hot spot.
But drifting further east
is a volcanic island
that last erupted over a million years ago.
Santa Cruz is situated
in the middle of the Galapagos chain.
It's thought to be
around 2 million years old.
Here the terrain is mixed.
Ranging from arid low land
to humid high altitudes.
Ancient volcanoes
have been swallowed by forest,
and the islands' peaks are high enough
to form rain clouds.
Cactus forests line the lower plains.
These succulent green plants store water
in their stems and leaves.
They thrive in hostile climates
during times of drought.
Most cactus species have spines
to guard against grazing animals.
But this isn't enough
to deter one Galapagos resident.
Cactus finches not only feed
on the plant's flowers.
They also nest among its leaf-like pads.
This particular bird may look ordinary,
but it became one of the most important
species in the entire archipelago
after Darwin put all Galapagos finches
on the map forever.
The Galapagos Islands
are home to another bird,
who's awkwardness on land
but precision out at sea
also helped influence
Darwin's theory of evolution.
Blue footed boobies use a unique method
to capture their prey.
They plunge dive in unison
from heights of around 30 meters.
They hit the water at just under 100 km/h,
reaching depths of 25 meters.
Meals are usually consumed
while still under water.
On North Seymour Island
just off Santa Cruz,
it's breeding season.
Over 20,000 pairs of blue footed boobies
live on the Galapagos Islands
around three-quarters
of the world's population.
This male attempts to woo a mate.
Blue footed boobies
take great pride in their feet.
This male shows them off
with a high stepping strut.
Females prefer partners with bluer feet.
And this girl seems impressed.
He hunches and crosses his wings
before sky pointing his bill.
The female mimics the male's behavior
indicating her acceptance.
Another ritual can now begin.
The male picks up a twig
and gently places it
at the female's feet.
This symbolic act of nest building
seals their relationship.
However, this couple
has some unwanted company.
Another male approaches.
Fencing with their long beaks
is how booby conflicts are resolved.
Eventually the intruder gives up.
The bachelor leaves
to try his luck elsewhere.
Brightly colored body parts play a vital role
in the courtship of another island resident.
Frigate birds
are the real masters of the skies.
Strong breast muscles
work together with their wings,
enabling them to fly fast and soar high.
Forked tails help them steer.
They have the largest wing span
to body weight ratio of any bird.
Males tip the scales at just over a kilo,
but their wings can stretch
to nearly 2-1/2 meters.
Frigate birds can stay aloft
for more than a week,
landing only to roost or breed.
This female is preparing to land,
but she's facing a tough choice.
The males below
have chosen potential nest sites.
They advertise their positions
in a most colorful, eye catching way.
With wings outstretched,
they inflate their enormous throat pouches
and call to the passing females.
The biggest and brightest air sacs
have the most appeal.
The female makes her choice.
And the male shields her
from the nearby competition.
After pairing, the male saws material
to construct their nest.
Frigate birds have such short legs,
they're unable to walk on land
or swim in water.
They can not take off from flat surfaces so
collecting twigs requires enormous skill.
Most of their food is obtained on the wing.
Robbing other sea birds in flight
can account for nearly half their diet.
Internal pilfering also plays a part
during nest building.
Parental care in frigate birds lasts longer
than that of any other bird species.
Both parents take turns
to feed their young
for the first three months.
After this,
the mother takes sole responsibility
for up to a year and a half.
Many creatures have evolved
in order to survive on the Galapagos.
However on South Plaza Island,
a plant has also been forced to change.
Unlike many cactus species, these plants
have grown extra long trunks.
Their fleshy pads and flowers
are the favorite meal
of a creature that roams this tiny island
in large numbers.
The beast, that Darwin referred to,
is hideous.
Land iguanas are large stocky lizards.
They can be over a meter long
and weigh up to 13 kilos.
They feed mainly
on low growing plants and shrubs,
which also provides them with moisture
during the islands' long dry periods.
Younger prickly pear
cacti have sharp spines
that grow on their fleshy trunks, pads,
and flavorful fruits.
The spines do little to deter the iguanas.
Rolling the fruit in soil
removes most of the spines.
Now it's ready to eat.
In time, the cacti grow taller,
and the spines on the trunk
are replaced by a thick, scaly bark.
These older plants
become too tall for the iguanas to reach.
However, the lizards still value
these tall structures.
Each iguana claims a tree.
They sit patiently in the plant's shade
for up to a month,
waiting for the right fruit to drop.
Feeding territories overlap due to the
large number of iguanas living here.
Claiming fallen fruit
isn't that straight forward.
This iguana bobs its head
towards the intruder.
It's a sign of aggression
meaning stay away.
Undeterred, the trespasser
steals his neighbor's bounty.
The central Galapagos Islands
are incredibly fertile,
playing home to a rich array of wildlife.
But far to the east lies an island
that's a shadow of its fruitful past.
Espanola is the oldest
of all the Galapagos Islands.
It's traveled approximately nine
meters east since Darwin's visit,
and over 160 km since its creation
around 4 million years ago.
This arid and relatively
flat island is dying.
The further it drifts
from the region's volcanic hot spot,
the more it cools, contracts and sinks.
Espanola's remote location
may be hostile to many creatures,
but the island's steep cliffs
serve as perfect runways
for one of the largest flying birds
in the world.
The waved albatross
stands over a meter tall
and has a wing span
approaching 2-1/2 meters.
Espanola is this bird's only nesting place.
The entire world population
relies on this island.
Each April, 12,000 breeding pairs
return to Espanola's shores.
Males are the first to arrive
followed shortly by their partners.
Waved albatross mate for life,
and the male begins
his annual courtship dance.
This performance of strutting, honking,
and beak clicking can last up to five days.
Once reacquainted,
the female lays a single egg.
Both birds
share the responsibility of incubation.
Feeding newly hatched chicks
also requires joint effort.
Both parents can make round trips
of over 3,000 km while out fishing.
The colony remains on Espanola
until December
when the chick is fully grown.
In January, most of the colony
leaves the island
to fish on the nutrient rich
Humboldt Current.
Young albatross won't return
for five or six years.
Only then will they be
ready to seek a mate.
Espanola is eroding away.
Waves crash into lava fissures
creating blow holes
that spray water
nearly 30 meters into the air.
The powerful Humboldt Current
will eventually swallow Espanola
and every other Galapagos island
heading this way.
The Galapagos Islands
are a wilderness of wonder.
Uninfluenced by people for so long,
they provided one man
with a unique snapshot of evolution.
Creatures here have adapted
to their ever changing environment
as the land beneath their feet
comes and goes.
Darwin's Eden-like wilderness
continues to be
a vital part of our
natural world's history.
Sun scarred landscapes.
And few signs of life
that early explorers
to name the Galapagos Islands
hell on earth.
But beyond these parched beginnings,
this volcanic archipelago
is now our planet's greatest Eden.
A wilderness so pristine and rich in life
it allowed one man's studies to alter
our entire view of the natural world.
Older islands fade away
while new ones emerge
from beneath the sea.
The Galapagos continue to evolve
and continues to be
nature's greatest evolutionary arboratory.
The Galapagos Islands rank among
the most spectacular
scientific discoveries in history.
Situated 1,000 km west of Ecuador
in South America,
the archipelago contains 13 main islands
and a hundred or so
smaller rocks and reefs.
Some are so desolate and barren,
they reveal few signs of life.
Others are rich haven providing a home
to bizarre and unique creatures.
Human influence has been so limited
across the islands,
it allowed one man to study and rethink
the laws of nature.
In 1835, 26 year old Charles Darwin
sailed to the Galapagos Islands
in HMS Beagle.
The ship's mission was
to survey the coast of South America.
Darwin was the ship's botanist.
Thirty years later,
Darwin published his theory of evolution,
one of the most revolutionary ideas
science has ever known.
It was the islands' small land birds
like finches and mockingbirds
that proved key to Charles Darwin's theory.
Each of the 13 species of finch
has a different beak
for a different purpose.
Some are thick and heavy
for crushing seeds.
Others long and pointed
for accessing pollen in flowers.
They all descended from a common ancestor
that arrived on the islands
millions of years ago.
The finches established themselves
and began to determine territories.
With no competition from other birds,
they diversified.
They developed unique adaptations
for each type of habitat.
New species were born.
Darwin explained that natural selection
was the driving force
behind this rapid evolution.
Following the publication of his theory,
these ordinary looking small birds
have been given a new collective name,
Darwin's finches.
The Galapagos Islands
were named after their giant tortoises.
The old Spanish word, galapago,
meant saddle.
A term early explorers
used for the tortoises
due to the shape of their shells.
The Galapagos tortoise
is the largest in the world.
Some reach a meter and a half in length
and can weigh 250 kg.
These slow moving reptiles
lead an uncomplicated life.
Most days are spent
grazing on grass and leaves
in between basking in the sun.
Like all reptiles,
giant tortoises rely on the sun
to warm their bodies
and become active.
However, the midday sun
can be too much to bear
even for cold blooded creatures.
Fortunately, the islands' lakes don't just
provide a valuable source of drinking water.
Bathing in the muddy shallows
is the perfect way to cool down.
A slow metabolism
and large internal stores of water
allow the tortoises to survive
for up to a year
without eating or drinking.
Inactivity also helps.
They sleep for around 16 hours a day.
These giants can live for over 150 years.
Darwin noted a variation
in the shape of the shell
of tortoises from different islands.
This became additional evidence
for developing his theory of evolution.
Galapagos creatures evolve
and adapt to their habitat.
And their island homes
are ever changing too.
The youngest islands furthest west
are still forming.
A static volcanic hot spot
1,000 km beneath the sea
continually forces lava to the surface.
These newly formed masses eventually cool
and then drag southeast
at a rate of 5 cm a year
from shifting oceanic plates.
On their 200 km journey east,
they witness many changes.
Ultimately all Galapagos islands
face the same fate.
Disappearing beneath the ocean
without a trace.
Darwin described how eager he was
to witness an active volcano.
Although there were no eruptions
during his visit,
his geological observations
altered many volcanic theories.
The newest and most westernly
Galapagos island is Fernandina.
Still situated
directly over the oceanic hot spot,
this volcanic mass has erupted 24 times
in the past 200 years.
It's one of the youngest
and most active volcanoes on earth.
Fernandina's peak
stretches 1,500 meters high
and its crater spans 6-1/2 km.
The island's lava clad rocky shores
and black sand beaches
seem the most forbidding
of all the Galapagos Islands.
Yet life has started to take hold.
Pioneer plants such as these lava cactus
are often first to take root.
Their seeds carry from older islands
by bird droppings
or directly by the wind.
But there is one creature
that has colonized the entire archipelago
and its mode of travel relies on the sea.
Marine iguanas are excellent swimmers.
They can reach over a meter in length
and weigh as much as 9 kg.
Over 250,000 of these swimming dragons
inhabit the Galapagos.
They are the world's only species
that marine lizard.
It's thought that millions of years ago,
land dwelling iguanas from South America
drifted out to sea on floating debris.
They eventually landed on the islands.
Isolated from the main land,
a new iguana evolved
and adapted to life at sea.
Like all iguanas,
this species is vegetarian.
Yet Fernandina offers very little
in the way of visible food.
But this species rarely goes hungry.
Being cold blooded, iguanas need to raise
their body temperatures
to approximately 36° C
in order to function.
After an hour or so
basking in the equatorial sun,
this iguana launches its feeding mission.
A flattened tail allows it to dive down
to depths of 12 meters
to access tufts of red and green algae
on the submerged rocks.
A shortened blunt snout allows it
to crop the plant close to its face.
This algae is the marine iguana's
exclusive diet.
Fernandina's currents
are surprisingly cold.
The iguana's body temperature
can plummet 10° on an extended dive.
After just 10 minutes,
its muscles begin seizing up.
Getting back to dry land in time
is critical to survival.
Long, sharp, recurved claws
enable the lizard
to hold fast to the lava in heavy seas
or when submerged.
Along with the algae, marine iguanas ingest
a great deal of salt.
Specially adapted glands above each eye
are connected by ducts to each nostril.
The excess salt is sneezed out.
Only the larger marine iguanas
risk running
the gauntlet of the islands' chilling seas.
Smaller individuals choose a safer option
and graze only at low tide on dry land.
Fernandina is less than
half a million years old
and offers little sanctuary
to land living creatures.
But drifting 75 km further east
are islands more than twice its age
and different worlds entirely.
Isabella is the largest
of all the Galapagos Islands.
Consisting of six overlapping volcanoes,
its over 100 km long.
It makes up half of the total land area
of the Galapagos.
The volcanic hot spot
still simmers beneath Isabella's seas.
While above the surface, a creature
key to Darwin's evolutionary theory
prepares to dive the deep.
This cormorant is unique to the Galapagos.
Its wings are disproportionately small
to the size of its body.
They're about one third the size required
for it to take to the air.
This species has evolved to be flightless.
Its legs are much stronger
than those of other cormorants.
Enlarged feet propel
its stream lined meter long body
in search of octopus and small fish.
Darwin noted that the flightless cormorant
could not have swum
from the mainland to the islands.
It never ventures
further than 100 meters from the shore.
It diverged from its flighted cousins
and eventually became marooned
on the islands.
An abundance of food
and an absence of predators
has allowed this mutant bird to flourish.
Its the largest of all cormorant species.
Seaweed makes the perfect nest material
on top of jagged lava rock.
Both parents play a part
in raising their young.
Although it can no longer fly,
the bird still holds its wings up to dry.
It's a memory left over
from ancestral habits.
Further inland, saltwater lagoons
provide the perfect refuge
to one of the world's most iconic birds.
Greater flamingos
usually live in large colonies
of up to 10,000.
The Galapagos plays home
to the world's smallest population
numbering less than 600.
Most of their day is spent feeding.
The shallow water enables them
to turn their heads upside down
and sweep from side to side.
They filter up to 20 mouthfuls a second,
separating brine shrimp
and small crustaceans
from the mud and silt.
The consumption of shrimp provides
the pink pigment of their feathers.
The small population size of the Galapagos
has resulted in changes
to their breeding behavior.
Flamingo populations elsewhere
rely on very large groups of birds
for breeding to occur.
Galapagos flamingos can breed
with just a few pairs present.
It's the start of the nesting season,
and their unique courtship ritual begins.
Males and females mate for life.
These coordinated displays
are key to reaffirming their bonds.
Wing salutes,
turning their heads in unison,
and twist preening
are important courtship signals.
The Galapagos flamingos
originally flew in from the Caribbean.
Whereas one mammal swam over 5,000 km
to set up home here.
Galapagos sea lions
arrived from California.
They're slightly smaller
than their North American relatives.
But at over 2 meters in length
and weighing as much as 250 kg,
they are by far the largest mammals
of the entire Galapagos Islands.
They're most likely
one of the first animals Darwin encountered
when he came ashore around 180 years ago.
Sea lions are well adapted
to a semi-aquatic lifestyle.
Along with a streamlined body,
they can control their hind flippers
independently.
This makes them far more agile
than true seals.
Females give birth to just one pup
and remain with them on shore
for the first week.
After this, they go off on foraging trips
that can last up to three days.
Pups left behind gather in nurseries
where they socialize and play.
One female remains behind to keep watch.
When returning from a trip,
females alert their pups
with distinctive calls.
These reunions initially
rely on the mothers.
But once they're older,
the youngsters call out too.
Pups are suckled for up to 12 months,
three times longer
than many other seal species.
Adult male sea lions
play no role in raising their young.
A dominant bull
also known as a beach master
spends the majority of his day patrolling
the territory occupied by his harem.
This particular male
has some unwanted company.
The intruder is defeated
for now at least.
Keeping other males at bay
is exhausting work.
Some beach masters succeed
for just a few days.
Even the toughest only manage to protect
their patch for a maximum of three months.
With the storm over, everyone can relax.
However, another predator
prepares to move in.
It's been patiently waiting
for the sea lions to drop their guard.
Lava lizards are carnivores.
This one has singled out its prey.
Flies are a constant irritation
to the sea lions
so they welcome
this free grooming service.
These Galapagos reptiles play an important
role in controlling insect populations.
Male lava lizards can live up to 10 years
and may have three or more mates
in their harem.
This male approaches one of his conquests.
He bobs his head up and down
to signal his intentions.
This female isn't ready or willing to mate.
Turning her back and raising her tail
lets the male know
he's been rejected.
The Galapagos Islands sit on the equator
except the climate here
isn't typically tropical.
The reason lies
within the surrounding seas.
Three major ocean currents
collide at the very point
where the Galapagos Islands lie.
The warm Panama Current from the north
supports the island's
more tropical marine life.
The icy Humboldt Current from the south
brings nutrient rich
waters from Antarctica.
And from the west,
the deep water Cromwell Current
rises to the surface
upon hitting the Galapagos shelf.
Elsewhere, the temperature at sea level
is usually warmer than at higher altitudes.
But here, the opposite is true.
The cold waters from the south and west
cool the air above them.
Colder waters are rich in green algae,
which supports
a diverse and vibrant food chain.
Over 500 species of fish
rely on these plankton rich seas.
Large schools of hammerhead sharks
patrol the islands' waters all year round.
This unusual looking predator
can reach over 4 meters in length.
Its eyes are a meter apart.
Darwin found the Galapagos
to be home to many unusual creatures.
But none more unexpected than this.
Galapagos penguins
descended from ancestors in the Antarctic,
10,000 km further south.
They are the only kind
living in the northern hemisphere.
It's thought they arrived
during the last Ice Age
after being swept north
by the Humboldt Current.
They later became stranded here
after the earth warmed.
The islands furthest west
still suffer the effects
of the Pacific Ocean hot spot.
But drifting further east
is a volcanic island
that last erupted over a million years ago.
Santa Cruz is situated
in the middle of the Galapagos chain.
It's thought to be
around 2 million years old.
Here the terrain is mixed.
Ranging from arid low land
to humid high altitudes.
Ancient volcanoes
have been swallowed by forest,
and the islands' peaks are high enough
to form rain clouds.
Cactus forests line the lower plains.
These succulent green plants store water
in their stems and leaves.
They thrive in hostile climates
during times of drought.
Most cactus species have spines
to guard against grazing animals.
But this isn't enough
to deter one Galapagos resident.
Cactus finches not only feed
on the plant's flowers.
They also nest among its leaf-like pads.
This particular bird may look ordinary,
but it became one of the most important
species in the entire archipelago
after Darwin put all Galapagos finches
on the map forever.
The Galapagos Islands
are home to another bird,
who's awkwardness on land
but precision out at sea
also helped influence
Darwin's theory of evolution.
Blue footed boobies use a unique method
to capture their prey.
They plunge dive in unison
from heights of around 30 meters.
They hit the water at just under 100 km/h,
reaching depths of 25 meters.
Meals are usually consumed
while still under water.
On North Seymour Island
just off Santa Cruz,
it's breeding season.
Over 20,000 pairs of blue footed boobies
live on the Galapagos Islands
around three-quarters
of the world's population.
This male attempts to woo a mate.
Blue footed boobies
take great pride in their feet.
This male shows them off
with a high stepping strut.
Females prefer partners with bluer feet.
And this girl seems impressed.
He hunches and crosses his wings
before sky pointing his bill.
The female mimics the male's behavior
indicating her acceptance.
Another ritual can now begin.
The male picks up a twig
and gently places it
at the female's feet.
This symbolic act of nest building
seals their relationship.
However, this couple
has some unwanted company.
Another male approaches.
Fencing with their long beaks
is how booby conflicts are resolved.
Eventually the intruder gives up.
The bachelor leaves
to try his luck elsewhere.
Brightly colored body parts play a vital role
in the courtship of another island resident.
Frigate birds
are the real masters of the skies.
Strong breast muscles
work together with their wings,
enabling them to fly fast and soar high.
Forked tails help them steer.
They have the largest wing span
to body weight ratio of any bird.
Males tip the scales at just over a kilo,
but their wings can stretch
to nearly 2-1/2 meters.
Frigate birds can stay aloft
for more than a week,
landing only to roost or breed.
This female is preparing to land,
but she's facing a tough choice.
The males below
have chosen potential nest sites.
They advertise their positions
in a most colorful, eye catching way.
With wings outstretched,
they inflate their enormous throat pouches
and call to the passing females.
The biggest and brightest air sacs
have the most appeal.
The female makes her choice.
And the male shields her
from the nearby competition.
After pairing, the male saws material
to construct their nest.
Frigate birds have such short legs,
they're unable to walk on land
or swim in water.
They can not take off from flat surfaces so
collecting twigs requires enormous skill.
Most of their food is obtained on the wing.
Robbing other sea birds in flight
can account for nearly half their diet.
Internal pilfering also plays a part
during nest building.
Parental care in frigate birds lasts longer
than that of any other bird species.
Both parents take turns
to feed their young
for the first three months.
After this,
the mother takes sole responsibility
for up to a year and a half.
Many creatures have evolved
in order to survive on the Galapagos.
However on South Plaza Island,
a plant has also been forced to change.
Unlike many cactus species, these plants
have grown extra long trunks.
Their fleshy pads and flowers
are the favorite meal
of a creature that roams this tiny island
in large numbers.
The beast, that Darwin referred to,
is hideous.
Land iguanas are large stocky lizards.
They can be over a meter long
and weigh up to 13 kilos.
They feed mainly
on low growing plants and shrubs,
which also provides them with moisture
during the islands' long dry periods.
Younger prickly pear
cacti have sharp spines
that grow on their fleshy trunks, pads,
and flavorful fruits.
The spines do little to deter the iguanas.
Rolling the fruit in soil
removes most of the spines.
Now it's ready to eat.
In time, the cacti grow taller,
and the spines on the trunk
are replaced by a thick, scaly bark.
These older plants
become too tall for the iguanas to reach.
However, the lizards still value
these tall structures.
Each iguana claims a tree.
They sit patiently in the plant's shade
for up to a month,
waiting for the right fruit to drop.
Feeding territories overlap due to the
large number of iguanas living here.
Claiming fallen fruit
isn't that straight forward.
This iguana bobs its head
towards the intruder.
It's a sign of aggression
meaning stay away.
Undeterred, the trespasser
steals his neighbor's bounty.
The central Galapagos Islands
are incredibly fertile,
playing home to a rich array of wildlife.
But far to the east lies an island
that's a shadow of its fruitful past.
Espanola is the oldest
of all the Galapagos Islands.
It's traveled approximately nine
meters east since Darwin's visit,
and over 160 km since its creation
around 4 million years ago.
This arid and relatively
flat island is dying.
The further it drifts
from the region's volcanic hot spot,
the more it cools, contracts and sinks.
Espanola's remote location
may be hostile to many creatures,
but the island's steep cliffs
serve as perfect runways
for one of the largest flying birds
in the world.
The waved albatross
stands over a meter tall
and has a wing span
approaching 2-1/2 meters.
Espanola is this bird's only nesting place.
The entire world population
relies on this island.
Each April, 12,000 breeding pairs
return to Espanola's shores.
Males are the first to arrive
followed shortly by their partners.
Waved albatross mate for life,
and the male begins
his annual courtship dance.
This performance of strutting, honking,
and beak clicking can last up to five days.
Once reacquainted,
the female lays a single egg.
Both birds
share the responsibility of incubation.
Feeding newly hatched chicks
also requires joint effort.
Both parents can make round trips
of over 3,000 km while out fishing.
The colony remains on Espanola
until December
when the chick is fully grown.
In January, most of the colony
leaves the island
to fish on the nutrient rich
Humboldt Current.
Young albatross won't return
for five or six years.
Only then will they be
ready to seek a mate.
Espanola is eroding away.
Waves crash into lava fissures
creating blow holes
that spray water
nearly 30 meters into the air.
The powerful Humboldt Current
will eventually swallow Espanola
and every other Galapagos island
heading this way.
The Galapagos Islands
are a wilderness of wonder.
Uninfluenced by people for so long,
they provided one man
with a unique snapshot of evolution.
Creatures here have adapted
to their ever changing environment
as the land beneath their feet
comes and goes.
Darwin's Eden-like wilderness
continues to be
a vital part of our
natural world's history.