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00:0090 degrees west.
00:2410 degrees south.
00:34A world lost in the vastness of the Pacific.
00:50Home to the strangest life imaginable.
00:56Governed by nature's brutal forces.
01:16Islands which have transformed our understanding of life on Earth.
01:40Galapagos lies remote, 600 miles off the coast of South America, astride the equator.
02:07A scattering of 13 main islands, with more than a hundred islets, rocks and reefs.
02:26Each island has its own character.
02:32Some are cloaked in forest, concealing life.
02:46Others smouldering giants, rugged and austere.
02:53Haunt of pirates.
03:00Lair of dragons.
03:12All are the creation of one of the strangest features found anywhere on our planet.
03:42Galapagos are no ordinary islands.
03:48A mysterious prehistoric world.
04:06A landscape that profoundly influences life.
04:28These islands are plumbed directly into the heart of the Earth.
04:37An archery of superheated rock rises to the surface from hundreds of miles beneath the
04:42crust.
04:50It's a volcanic hotspot.
05:05Galapagos constantly simmers, even beneath the waves.
05:20These tiny bubbles of gas give a vital clue to the genesis of the islands.
05:34Sea vents are like pressure valves, releasing growing tension from chambers of molten rock
05:40beneath the crust.
05:48And if the pressure gets too much, this magma reaches bursting point.
06:08The largest of all the Galapagos volcanoes, Sierra Negra, recently blew smoke and ash
06:15seven miles into the sky.
06:45The only rivers here are rivers of red-hot rock, at a scorching 1,100 degrees Celsius.
07:11Galapagos is one of the most volcanic places on Earth.
07:28The hotspot has been active for millions of years, building island after island.
07:42But it's not just how these islands are born, but where they're born that makes Galapagos
07:47so special.
07:53They've emerged at the crossroads of four major ocean currents, sweeping in from all
07:58corners of the Pacific.
08:05This interplay of warm and cold currents generates an extraordinary diversity of marine life.
08:21Over 500 species of fish make the most of these plankton-rich waters, among them residents
08:29like these barnacle blennies and strange garden eels.
08:47Even ocean travelers like scalloped hammerheads gather in huge numbers.
08:57The converging currents that envelop Galapagos have also brought creatures to these shores
09:02from opposite ends of the Pacific.
09:18Galapagos sea lions are related to Californian sea lions that came here from the north.
09:28And from as far south as the sub-Antarctic swam the ancestors of these birds, Galapagos
09:35penguins.
09:46The cold waters here allow them to survive on the equator.
09:57Fish shells like these seek refuge from open ocean predators by keeping near the shoreline.
10:06But in Galapagos, this strategy can be risky.
10:12The coastal margins are the feeding grounds for the most aerobatic hunters.
10:20Blue-footed boobies.
10:25When the fishing's good, they gather in their thousands.
10:35Fishing calls synchronize an assault.
10:50Plunging in unison overwhelms their prey.
11:17Blue-footed boobies can dive in waters just three feet deep.
11:39But as they chase the shoals further inshore, they risk treacherous undercurrents and hidden rocks.
12:03The biggest hazard is the battering surf.
12:32A wing smashed by the breakers means slow and certain death.
12:43Ghost crabs normally sift the sand for food, but they've always got an eye out for something meatier.
13:10For creatures of the sea and air, Galapagos is a welcome sanctuary.
13:19But these islands are not a choice destination for land animals.
13:27Those that came here were probably victims of flash floods swept out from the mainland on rafts of floating trees.
13:38Crossing 600 miles of ocean with no food and no fresh water.
13:51For any survivor, landing in a place like this would be a daunting prospect.
14:01Fernandina is the harshest, most volcanically active of all the Galapagos Islands.
14:08A lava-scarred giant.
14:14This is a single monumental volcano with a caldera half a mile deep and nearly four miles wide.
14:36Where the volcano meets the sea, dragons stir.
14:52It's hard to tell a reptile from rock.
15:08These creatures are found nowhere else on Earth.
15:19At dawn, the cold-blooded iguanas thaw from the night's chill, absorbing the heat of the equatorial sun.
15:29When they've warmed, the coastline of Fernandina comes alive.
15:38On this island, food is scarce.
15:45And the only way to find it involves a mission that seems suicidal.
16:07Only the larger adults dare to take the plunge.
16:23Marine iguanas are strong swimmers.
16:27With a single breath, they can comfortably dive to 30 feet.
16:43And all this effort for red and green algae, which thrive in the cold water.
16:54Marine iguanas are the world's only sea lizards.
16:57But when their distant ancestors were washed ashore in Galapagos, they were land animals.
17:05To survive, they were forced to tackle the ocean.
17:17This male must graze as quickly as he can.
17:20In these chilling waters, his body temperature falls fast.
17:25A 10-minute dive is about the most he can manage before his muscles seize up.
17:47Fighting the surge back to the shore is a Herculean task.
18:05And to make matters worse, he must now run the gauntlet of sea lions.
18:16They are the last thing the iguana needs.
18:25No harm is meant.
18:27There's nothing more than a rather one-sided game of cat and mouse.
19:27Marine iguanas take in too much salt with their food.
19:42But with the help of special glands, they sneeze it out.
19:57They also welcome these resourceful visitors.
20:19Sally Lightfoot crabs like to groom them for algae, parasites and dead skin.
20:35Larvae lizards, far smaller reptilian relatives, have found their own ingenious ways to get
20:41by on this fierce shoreline.
20:51They enjoy a special relationship with the sea lions.
20:57The lizards rid them of flies, which can be a ticklish nuisance.
21:21This sea lion accepts these predatory lizards.
21:29Both benefit.
21:40Survival depends on seizing every opportunity in this volcanic wasteland.
21:50Fernandina is the youngest of all the main Galapagos Islands.
21:56It may have raised its head above the waves as recently as 30,000 years ago.
22:05It sits right above the volcanic hotspot in the far west of the archipelago.
22:12But how is it that the other islands, created at this same hotspot, are now scattered over
22:18hundreds of miles of ocean to the east?
22:29All the islands are moving.
22:36They are traveling southeast at an inch or two a year on a massive tectonic plate, which
22:42continually slides over the hotspot.
22:52Their journey begins as soon as they are born.
22:58And in their wake, new islands emerge.
23:08It's like a geological conveyor belt.
23:21So the archipelago we see today is just a snapshot in time.
23:26The oldest islands are in the east, the youngest in the west.
23:34And as Fernandina ages, it will be carried on this conveyor belt to where the biggest
23:39of all the Galapagos Islands currently resides.
23:45Isabela.
23:48It's shaped like a giant seahorse, almost a hundred miles long, with a backbone of volcanoes.
24:00Isabela is a teenage Galapagos island, nearing a million years old.
24:06Time enough for life to settle.
24:14Its giant calderas still tower more than a mile above sea level, and are draped in vegetation.
24:32Although Isabela is softening with age, it's still close enough to the hotspot to remain
24:38active.
24:48On its summits, like here on Alcedo volcano, live the most iconic of all Galapagos animals.
24:57Their ancient trails, carved over tens of thousands of years, scar the landscape.
25:09Giant tortoises.
25:14They are the largest of their kind in the world, weighing up to 550 pounds.
25:26Water is a scarce resource on this island, and giant tortoises can survive months without it.
25:38But during the wetter season, they gather to quench their thirst among a scattering
25:42of freshwater pools.
25:47A tortoise oasis.
25:53Around 5,000 live here on Alcedo.
25:56It's the greatest concentration found anywhere in Galapagos.
26:13Despite their extensive body armor, tortoises are vulnerable to skin parasites, which they
26:19are unable to remove themselves.
26:22So they've developed a remarkable relationship with finches.
26:31When they need a service, it's a sort of slow-motion pit stop.
26:55A finch-feeding frenzy.
27:05This giant tortoise could live to be 150 years old.
27:13During his lifetime, the island he roams, Isabela, will be transported about 20 feet
27:19southeast on the Galapagos conveyor belt.
27:23But a million years from now, that's about 6,000 tortoise lifetimes, Isabela will be
27:31carried right to the heart of the Galapagos archipelago, to where these mature, middle-aged
27:38islands now lie.
27:45Santa Cruz has been pulled so far from the hotspot that its volcanoes are now ancient
27:51ruins, worn by the passage of time and swallowed by forest.
28:00Plants and soils now cover this aging island, teeming with life.
28:22Its peaks are still high enough to generate clouds and receive regular rainfall.
28:29It's one of the few places in Galapagos where there are magical freshwater pools.
28:39After a morning spent foraging at sea, frigatebirds come here to bathe their feathers and to sip
28:47on the wing.
28:58These forest basins are created by layer on layer of rich volcanic soil, packed over porous
29:05lava.
29:07Elsewhere, the water filters its way through to re-emerge near the coast in brackish lagoons.
29:15They're home to the most unlikely Galapagos residents.
29:22Greater flamingos chance immigrants from the Caribbean.
29:44There are only about 500 flamingos in Galapagos, limited to this rare habitat.
30:15Along the margins of these mature islands, where it's drier and hotter, the landscape
30:32is dominated by giant cactus forests, offering a perfect watchtower for the island's top
30:40land predator, the Galapagos hawk.
30:47Something on the shoreline catches its attention.
31:00Small lizards, birds and insects are the normal quarry, but for a few weeks a year there's
31:08much more on offer.
31:14Marine iguanas prefer to keep to the water's edge, but during the nesting season, females
31:19must brave it inland to find soft soil in which to lay their eggs.
31:27But she must go carefully.
31:38The hawk patiently waits to see if she drops her guard.
31:46She's reasonably safe close to her nest burrow, but stray too far from cover and she's caught
31:58in trouble.
33:16The family has timed its breeding to coincide with this plentiful supply of food.
33:27Both parents take turns to hunt for and feed their growing chick.
33:36He's only a few weeks old, but he's got a healthy appetite.
33:43He can comfortably eat half an iguana a day.
34:06As the Galapagos Islands are carried further and further away from their place of birth,
34:11the volcanic hotspot, there's a remarkable progression.
34:18From barren rock and ash-covered deserts, life gets a grip, creeping inland to mellow
34:29and diversify.
34:33But the story doesn't end there, for every island is destined for a spectacular final
34:40flourish.
34:44The oldest of them all, almost a hundred times older than Fernandina, lies on the southeastern
34:50perimeter of the archipelago.
35:00Once a much larger volcano, all that remains is a dry, flat scrap of land.
35:07This island is dying, but it's been carried to a place where the nutrient-rich Humboldt
35:14Current gives it a last breath of life.
35:24Its leeward northern shores have softened through time and they're a choice hangout
35:30for Galapagos sea lions.
35:39A male controls a stretch of coastline attracting up to 30 females and their young.
35:46Females give birth to a single pup, nourished on milk rich in protein and fat.
35:54When the pups are about a month old, they join the local creche.
36:05It looks like a baby, but it's not.
36:10It's a baby, but it's not.
36:15It's a baby, but it's not.
36:21It looks an easy life.
36:35But for this 500 pound beach master, there's no time to relax.
36:40Even with every ounce of effort, he'll be lucky to rule this stretch of sand for more than three weeks.
36:50This is why there are constant challengers.
37:20This is why there are constant challengers.
37:25This is why there are constant challengers.
37:30This is why there are constant challengers.
37:48This time the beach master wins, leaving his rival battered and scarred.
38:01When the young sea lions are a year or two old,
38:06the bay becomes a training ground for social and hunting skills.
38:24These waters are so rich and the sea lions such effective predators
38:29that it frees up time to enjoy.
38:59These waters are so rich and the sea lions such effective predators
39:04that it frees up time to enjoy.
39:29These waters are so rich and the sea lions such effective predators
39:34that it frees up time to enjoy.
39:48Few sea creatures are as playful.
39:53Though the northern side of Española is reasonably sheltered from prevailing winds,
39:58Though the northern side of Española is reasonably sheltered from prevailing winds,
40:03the southern side takes the full brunt of everything the ocean throws at it.
40:08the southern side takes the full brunt of everything the ocean throws at it.
40:16Yet these cliffs are a mecca for seafaring iguanas
40:21and a crucial nesting platform for resident seabirds.
40:36The most majestic of all is a visitor,
40:39an ocean wanderer that roams the whole eastern Pacific.
40:44The waved albatross is the largest bird in Galapagos,
40:49The waved albatross is the largest bird in Galapagos,
40:54with a seven-foot wingspan.
41:14After six months in the air, first touchdown is never that simple.
41:34Virtually the entire world population,
41:3912,000 breeding pairs, nest here on Española.
41:46The male waits for days, sometimes weeks, for the arrival of his partner.
41:51Waved albatrosses may live for up to 50 years and pair for life.
42:07Waved albatrosses may live for up to 50 years and pair for life.
42:12They rebond with a mesmerizing courtship dance.
42:22Waved albatrosses may live for up to 50 years and pair for life.
42:36The whole colony comes alive with the clack of beaks.
42:51The whole colony comes alive with the clack of beaks.
42:56For such huge birds, mating is a gentle affair.
43:26For such huge birds, mating is a gentle affair.
43:47The name waved albatross comes from the delicate pattern of their feathers.
43:57Everything is gambled on a single egg,
44:02which is incubated by both parents for two months,
44:07with each sitting for up to two weeks at a time, sometimes longer.
44:13And the result of such careful and diligent nurture is this.
44:26As the chicks age, their parents' foraging missions take them further and further afield,
44:31involving round trips of up to 2,000 miles.
44:41The chicks are fed on predigested squid and fish,
44:46guzzling nearly half a gallon of oil in one big hit.
44:56And then they're off.
45:17Finally, after almost six months,
45:22the chicks begin to take to the air.
45:40The young albatrosses won't be back to breed for another five or six years.
45:46Their journey is just beginning.
45:55But this island's journey is nearing its end.
46:00Life here outlives the land.
46:06During the last three and a half million years,
46:11Antarctica has travelled over 100 miles from its place of birth,
46:16the Galapagos Hotspot.
46:24Through that time, it's been cooling and contracting,
46:29fracturing and sinking.
46:35One day, it will end up beneath the waves.
46:41All the islands will eventually follow,
46:46carried on the conveyor belt to meet the same fate.
46:52Countless Galapagos islands have come and gone.
46:58They always have, and they always will.
47:12Just as the islands mature through time,
47:17so has our understanding of what makes them special.
47:23The first person to set foot on Galapagos
47:28prayed only for deliverance from this wretched place.
47:35In the centuries to follow,
47:40one man from London shared his view.
47:49But in time, one man, inspired by the landscape and wildlife,
47:54would see things differently,
47:58discovering a secret that lay hidden within this island universe.
48:04A secret that would transform not just how we saw these islands,
48:09but our understanding of life on Earth.
48:15His name was Charles Darwin.
48:30In the next programme, we travel deeper into the heart of Galapagos
48:36and find out why these islands, more than anywhere else,
48:41are such a crucible for new life.

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