"BIRD SQUAWKS" "60 million years ago, on the shores of this tropical island, an extraordinary story began." "The waves brought ashore an odd band of survivors... a few ancient creatures that had been accidentally swept across hundreds of miles of ocean from a distant land." "They found themselves here, in a place unlike any other." "Totally cut off from the rest of the world, these castaways made this island their own, gradually evolving into a collection of wildlife that's strange, rare and utterly unique." "So rare that more than 80% of the species are found nowhere else on earth." "The island was Madagascar." "This is the story of what happens when a set of animals and plants are cast away on an island for millions of years." "This is how this curious wonderland came into being." "It had all begun millions of years earlier when a great slab of land broke apart to form the continents as we know them today." "Africa went one way, and India went the other, and an orphaned chip of land was cast adrift, and ended up hundreds of miles from the nearest land." "Its unusual geological history, its isolation, and its resting place in the tropics, were to shape Madagascar's fortunes." "It's the world's oldest island, and it's had time to develop an astonishing range of landscapes." "It's split in two by a spine of mountains that runs its entire length, and each side has its own character." "On the western side lie huge forests populated with strange, bulging trees." "Further south, an alien world..." "a parched and sandy wilderness, with an immense lake of salt, and gnarled and twisted spiny woodlands." "And on the eastern side, lush jungle drenched in rain." "It's this combination of long isolation and varied landscapes that's created the eccentric diversity of wildlife which makes this island so special." "These rainforests are unlike any other rainforest on earth, and they are home to Madagascar's most successful inhabitants." "They are lemurs." "There are 80 different types, from nocturnal, mouse-sized creatures to this, the biggest, the size of a child." "It's an indri." "They are direct descendents of those first primitive mammals that had washed in from Africa by chance, and now they live nowhere else." "PIERCING SQUEAL" "CALL IS ANSWERED BY OTHERS" "They have almost dog-like faces." "But they are primates, related to us." "And when you watch them, you can see it." "They are highly social." "At two years old this young male is an adolescent, but he's still close to his mother." "His little sister is just six months old." "This family group will stay together for several more years." "Lemurs also have the grasping hands and feet of all primates." "It's fundamental for a life in the trees... as well as an effective way to put a stranglehold on an older brother." "For an indri, childhood is long." "It's nine years before they are fully adult." "There's plenty of time for play, and perfecting their impressive jumping skills." "And perhaps even a spot of showing off." "Everywhere you look, Madagascar has echoes of elsewhere... at first glance similar, but with different origins." "On the rainforest floor, an animal emerges that might be mistaken for a hedgehog." "But she's only the most distant relation." "She's a tenrec, another of Madagascar's own inventions." "And these are her youngsters." "Dozens of them." "Tenrecs have the distinction of giving birth to more babies than any other mammal on earth - as many as 32." "Her babies are stripy, the better to hide in the shadows of the rainforest floor." "Their ancestors too had washed in from Africa and, like the lemurs, they have diversified into many different species." "As well as being Madagascar's equivalent of hedgehogs, tenrecs also take the place that moles and shrews would occupy anywhere else in the world." "Madagascar's rich forests have been isolated from outside influence for so long, they have become an evolutionary cauldron, producing increasingly extreme forms of life." "And none are stranger than this." "It's a giraffe-necked weevil, and this is a male." "And this is the reason for his extra long neck." "He uses it for fighting." "Meanwhile a female weevil, who's not quite as long-necked, is beginning an ambitious construction project." "She's snipping through the leaf's veins, and making little creases in it." "She also appears to referee the fight." "She finally mates with the winner." "Then, using her powerful legs, the female starts to fold the leaf in half." "She then curls up the end," "and inside the curl, she lays a single egg." "All around the rainforest edge, females are busy rolling and curling their leaf nests." "Each seems to have her own design." "Only in these particular rainforests, and only on this one particular type of soft leaf, are conditions right for her to make her nest." "It's an astonishingly specific behaviour." "The expectant fathers are apparently just getting in the way." "But they may be guarding against tiny insects that would parasitise the newly laid egg." "The female has bitten tiny notches along the leaf's ribs, to form a kind of Velcro strip to help all it stick together." "A few final folds, and the nest is complete." "When she finally snips the leaf roll off, it falls to the forest floor to hatch." "All that effort for just one egg." "Madagascar has had a turbulent past." "At its birth it was ripped from India and Africa, and the geological upheavals have continued since." "The north of the island is speckled with slumbering volcanoes." "On the forested slopes lives another Madagascar speciality." "A chameleon!" "Chameleons weren't amongst those pioneering castaways." "Theirs is a different story." "It's thought that they evolved here in Madagascar itself." "They are wonderfully adapted to a life in the trees." "Their toes are fused, so their feet grip like tongs, and the arrangement of their legs is unusual for a reptile... they're beneath their body." "This allows them to walk on branches thinner than their body." "A male panther chameleon, one of the biggest." "A second male is in his tree." "He won't like that." "If the intruder doesn't back down, there will be trouble." "They are evenly matched - it's neck and neck." "HISSING" "The territory holder wins, and the loser takes the quickest way out." "In these isolated forests, chameleons have taken a variety of paths, and have diversified to an astonishing degree." "Some are miniatures, and have the rich forest floors to themselves." "A pygmy chameleon, the world's tiniest reptile, tiptoes through the leaf litter on the steep volcanic slopes." "She's so tiny, she's scarcely bigger than an ant." "And over here, in a forest of toadstools, a male." "He's looking for her." "He's even smaller than she is." "Finding a mate in a giant world is challenging." "And it's somewhat hazardous, when you could get run over by a millipede." "It takes a while, but when he finally reaches her, he has a special tactic." "He's not going to let go." "They're not mating, simply riding around until the time is right." "He barely touches her... just an occasional gentle little sway." "They can go round like this for days." "But at least they won't lose each other in their big volcanic forest." "The heart of Madagascar still rumbles with geological activity." "The centre of the island is a wide plateau of uplifted rock." "Here there are still thousands of earthquakes every year." "Over aeons of time, millions of these tiny earthquakes have torn a vast hole right in these central uplands, forming this, Madagascar's biggest lake..." "Lac Alaotra." "Around the edges of this massive body of water, there are reed beds." "But the vegetation is not fixed." "It floats in great mats in water three metres deep." "It's tricky and inaccessible to most." "But one creature has adapted to live here, and only here." "This is the Lac Alaotra reed lemur." "Not only is it small enough to climb the thinnest reeds, it can also survive on a diet of tough grass." "Unusually for a primate, it lives its whole life over water." "And it only lives on this one lake." "This family group has a patch of reeds to themselves." "But they have a problem - to find enough to eat, you have to move from reed bed to reed bed, and that takes skill and practice." "These lemurs can swim, but they prefer not to." "So they have developed a special technique for crossing the reed beds without ending up in the water below." "Their mother is an old hand." "Even with a baby on her back, she is surefooted, and her older children are getting the hang of it." "These lemurs are so specialised that they would struggle to live anywhere else." "While Madagascar's centre was shaped by volcanic fire, the western side of the island has an entirely different story." "For millions of years, this landscape was drowned, and layers of limestone formed underwater." "When the ocean finally retreated, this is what was left." "It's a gigantic, ancient reef." "The seabed was pushed up, creating a great block of limestone." "Over time, it's been carved by water into forests of giant pinnacles." "This is the Tsingy - one of Madagascar's strangest landscapes." "Underneath, it's riddled with caves, dissolved away by underground rivers." "In places the limestone has collapsed, creating deep canyons, and in among them have grown little oases of forest, filled with oddities." "The isolated forests are rich sources of food, but not easy for outsiders to reach." "The great walls of rock make moving between them, across razor sharp blades of stone, seem impossible." "Not so." "This too is the haunt of lemurs." "This most diverse group of primates has adapted to thrive all over the island, even here." "These are crowned lemurs." "They don't live up here, but they must cross the peaks to find fruiting trees in the forest pockets." "Exposed to the tropical sun, it's devilishly hot." "The group seeks shelter and a brief respite." "The lemurs are vulnerable here, and need to get a move on." "There's still a way to go before they reach the forest." "They get to what looks like the most daunting part of the journey - a 30-metre drop where the limestone has fallen away to create sheer cliffs." "But crowned lemurs are as good at rock climbing as they are at tree climbing." "Once down, they'll find shelter from the heat and plenty to eat." "But they must be on their guard." "There is one danger that every lemur on the island fears, a hunter that climbs as well as they can - the fossa!" "No big African predators made it to Madagascar." "There are no lions, no leopards, no wild dogs." "Instead the island's top predator is a giant mongoose." "And it eats lemurs." "But it has more curious habits." "It's the mating season, and this female has stationed herself 15 metres up a tree." "She's chosen a branch that will just support her own weight, plus that of a male." "A male approaches." "If she approves of him, she'll allow him to mate." "If she doesn't, she'll back away to a thinner branch, and he won't be able to get to her." "She's only fertile for a few days a year, so setting herself up in this tall tree is a good way of advertising her availability to suitors." "And it seems to work." "This is the sixth male she's entertained today." "The great diversity of Madagascar's wildlife is driven not only by the variation in landscape but also by the climate." "The spine of mountains running the length of the island blocks the rain blowing in from the east." "While the east coast is drenched year-round, the west lies in a rain shadow." "The plants that have evolved here have had to adapt to an arid world." "Some places get less than a tenth of the rain that falls in the rainforests of the east." "This is the land of the baobab." "These bizarrely shaped trees evolved to store water in their trunks." "They are tough and can live to a great age." "This baobab may be over 1,000 years old." "In these desiccated landscapes, many plants have evolved these bloated trunks to store water for the driest times." "The west of the island is dotted with these fat oddities." "Many survive by just clinging with long roots to cracks on bare rock." "Like most plants here, this uncarina stores water in its stem." "And it is also economical with its flowers, putting out a few a day, over several months." "This gives maximum opportunity for pollinators to visit." "But this is not what the uncarina needs, a sunbird has become a nectar thief." "Piercing the base of the flower it by-passes the pollen entirely." "But the sunbird is not alone." "Unfortunately for the shrub, it's another flower bandit." "In a place as tough as this, a flower is well worth the effort." "Madagascar is 1,000 miles from end to end." "The variation from north to south is extreme, and the further south you go, the drier it gets." "Most of the time, the rivers here are barely ankle deep." "But there's just enough water and nutrients for a fringe of forest to take hold." "And in Madagascar, where there's forest, there are lemurs." "These are sifakas." "They are superb acrobats, adapted to leaping from trunk to trunk." "But where the gap is too great or in more open stretches of river bank, they abandon the trees and do something extraordinary." "Their hind legs are too long to walk on all fours, so they stay upright, and gallop." "These river forests are an oasis in this dry landscape." "That can lead to some spectacular competition for territory." "A female paradise flycatcher is busy building a nest." "Both male and female have red feathers, but the males are particularly striking, with long tail plumes and bright blue rings round their eyes." "Curiously, although all males start out with red feathers, some males turn completely white." "No-one knows why, but it's something that's exceedingly rare in birds." "Another Madagascar oddity." "The red female and her white partner construct the nest between them." "It's a delicate affair, built of leaves and grasses woven together with cobwebs, and it takes days of careful work." "A red male watches nearby, breeding territory is particularly jealously guarded." "The white male must see him off." "Danger averted, the couple return to work." "But there's worse to come..." "..a drongo!" "For some reason it sets about destroying the carefully-made nest." "There is nothing the flycatcher couple can do about it." "SQUAWKING" "The drongo isn't even stealing the material, just chasing the flycatchers from their territory." "Competition for space is that fierce." "The female gives up and leaves." "Maybe she'll look for a more assertive male." "Go far enough south and the island changes once more, into a landscape of scrub and spines." "This place may go years without rain." "Strangely, there is water here." "This vast lake is ten-miles long, and just two-metres deep." "But it's not what it seems." "Greater flamingos fly 250 miles from Africa to breed here." "But they pretty much have it to themselves, because this is not fresh water, it's a salt lake, gradually evaporating in the heat and drought, and it's hostile to life." "This whole area has been getting drier for the last 40,000 years." "But the plants and animals here are uniquely adapted to extreme aridity." "Mornings are surprisingly chilly." "A rare Verreaux's coua, found only round this lake, puffs itself up until it's almost spherical." "Ring-tailed lemurs sunbathe too." "The most adaptable of all the lemurs, they can cope with the dryness, but they can't go without water entirely." "RUSTLING AND CHIRPING" "A giant fig, surprisingly and persistently green, wafts its thirsty roots across the ground." "There's water here somewhere, but it's hidden." "It's part of a southern river system that flows underground here, carving holes into the limestone like a Swiss cheese." "But it can only be reached in a few places." "For the ringtails, it's a life-line, and they visit every day." "In the water, too, there are curiosities... strange white fish, found only in these caverns." "They have been trapped in these underground rivers for millennia, and they too have gone their own way." "They have not only lost all their pigment, they've lost their eyes too." "They also swim upside down." "This may be to help them feed on the surface, but in a dark world, it barely matters which way is up." "Here in the far south of the island, the extreme conditions make this a land of rare specialists." "There is wildlife that's found nowhere else in Madagascar." "A little nocturnal mammal, whistling in the dark." "It's Grandidier's vontsira, one of the world's rarest carnivores." "They survive on a diet of almost nothing but insects." "As the climate here dried, only the toughest and most adaptable stayed on." "Grandidier's vontsira, able to survive on such a diet, was able to hang on." "THEY SQUEAL" "They're sociable, and playful." "But their lives remain largely a mystery." "The intense dryness of this end of the island has demanded some ingenious behaviour." "In this desert scrubland, desiccation is just as problematic for a spider as for a mammal." "An empty snail shell would make a perfect refuge from the heat." "But it's not safe lying on sand." "So this spider begins an astonishing process." "It attaches silk to the shell, and starts to haul it into a bush." "This is the first time this has been filmed, and may be the first time it's even been observed in the wild." "Each new strand is shorter than the last, so the shell gradually gets pulled up." "Technique is key." "It's important that the shell is secured from several angles, for maximum stability." "This spider has got it wrong." "And when the wind springs up, it totally loses control." "This one shows how it should be done." "This is the farthest southerly point of Madagascar." "Beyond this is nothing until you reach Antarctica." "This is the oldest, most arid and most remote landscape of all." "The spiny trees are dwarves, bent by the wind." "And on these windswept cliffs there are radiated tortoises, one of the world's most beautiful species." "They're only found in these southern scrublands." "A male sets off in pursuit of a female." "He'd be able to mate with her if only he can get her to stand still." "He uses the front of his shell to lift her back legs off the ground." "She seems less than willing." "It's a slow process, but radiated tortoises don't do anything very quickly." "They don't become parents until the age of 20, and they may live to be 130." "One legendary individual was claimed to be 188, which would make him the longest-living animal on earth." "It's also one of the most endangered." "It's hunted, and its unique spiny habitat is being destroyed, bit by bit, cut down for firewood." "It was once abundant on Madagascar." "Now it could well be extinct in the wild within the next 20 years." "On this same windswept beach lie thousands of fragments of egg shells." "These are the ancient nest sites of an astonishing creature... the biggest bird that ever lived." "The elephant bird stood more than three meters tall, and a thousand years ago it would have roamed these spiny scrublands." "In the warm sand it laid its huge eggs... bigger than dinosaur eggs." "This astonishing bird only lived in Madagascar, and it was extraordinarily successful." "But then, it totally disappeared." "These egg fragments and bits of bone are all that remains to show it was here at all." "Two thousand years ago, humans first came to Madagascar, and it seems the elephant bird started to vanish soon after." "It's a story that's continued." "Many of Madagascar's wild landscapes and species are under threat of disappearing forever, just as we are beginning to discover and understand the extraordinary diversity of life here." "It's only during the last few decades that we've really started to appreciate this curious land." "Let's hope it's not too late." "Much of Madagascar's wildlife is secretive, and a challenge to find, let alone film." "The team were keen to tell the story of a little lemur that only lives on this one remote lake." "There are very few of them left, because they've long been hunted, and the reed beds where they live are being cut down." "But in one village on Lac Alaotra, the local people have made strenuous efforts to save the reed lemurs, and they knew where they might be found." "Field assistant Jonathan Fiely and cameraman Gavin Thurston set out with local fisherman and wildlife guide Ndrina Rajohonson, who has spent many months following the lemurs." "The team wanted to film its specialised way of moving through these floating beds of reeds." "Easy for the lemurs... not so easy for a film crew." "In fact, in the tangled reed beds, it seemed almost impossible even to see them at all." "They are so nimble, they simply melt away into the reeds." "The team negotiated the channels in an attempt to track them down." "The trouble was, there's no dry land here." "Gavin would have to try and film them from a canoe." "Following a cyclone, the lake was deep and the water particularly choppy." "We're going to need a bigger boat!" "It's way too rocky, and the boat's going all over the shop." "We've got a few toys up our sleeves... we've got a big stick, to help stabilise the canoe." "This must look like sort of Amateurville, and it is quite precarious... you know, we've got sort of ã40,000-worth of camera balanced in a rocky canoe, which looks like we've just hired it from the local boating lake." "But I'm feeling positive." "It was back to base for Plan B." "Gavin and Ndrina decided to build a platform." "But it would have to be very carefully designed." "It turned into quite an undertaking." "We're trying to adapt this construction, so that when we get out to the reeds we don't need to use any nails at all." "I'm just worried that if they start banging the nails it's going to drive these animals even deeper into the reeds, so we're making this precarious 4-metre high platform above the water without any nails." "At dawn the next day, the platforms were loaded up to be taken out to the reed beds." "Getting the canoes through the tangled vegetation was hard enough." "Moving through with the platforms was a different matter." "And the whole operation had to be completed as quietly as possible, for fear of scaring the lemurs." "One false move and the whole team would end up in the water." "At last, a clear and stable view through the reed bed." "Gavin got himself settled and started filming." "But it wasn't easy." "The very thing he wanted to film, the lemurs on the move, was limited by the fact that when they moved off, Gavin could only wait for them to return." "It is quite frustrating really... because it doesn't matter how much experience you've got, with something like this... filming from the boat was too wobbly, and working off the platform you're literally stuck in one place in the hope that they'll come within sight." "I think we'll get it, in-between that and this sort of cyclonic weather." "THUNDERCLAP" "Just as they'd got set up, a storm was rolling in." "The last place you want to be is on a lake, in a canoe, in a thunderstorm, so they paddled back as quickly as they could, and then could only wait for the storm to pass." "That took three days." "Finally, it dawned clear and calm." "Things were looking more promising." "(Gavin's just inside the reed-bed right over there." "(We set him up about 5.20 this morning.)" "The team were in luck." "The lemurs were feeding right next to where Gavin was stationed." "With Ndrina's careful guidance, they were in the right place at the right time." "It might look a bit Heath-Robinson, but at last Gavin was getting shots of one of the world's rarest lemurs, moving and feeding in the reeds, and for the first time, a mother and her baby." "But even after ten days, they were still unpredictable." "(It's 7 o'clock in the morning... (and they've gone to sleep!" "(They're just tucked down in here asleep.)" "I've really quite grown to like them... it's just quite sad that they are critically endangered." "They only live in the reeds around this one lake, and there's very few small areas of reeds left, and if those reeds do disappear, then the lemurs are going to disappear with them." "And I think it would be really sad to lose such a cute cuddly little lemur like that." "These little lemurs have been pushed to the brink of extinction by hunting, and the gradual destruction of their reed beds." "But the quiet determination of people like Ndrina mean that local attitudes are beginning to change." "Madagascar is one of the poorest countries in the world." "It's as much as most people can do to earn a basic living from the land." "And yet it may be the passion and involvement of local people that is key to preserving its unique, and increasingly fragile, wild treasures." "In the next episode we travel into Madagascar's most luxuriant landscape." "Between the wild peaks of the eastern mountains and the tropical shore lies a magical world of rainforest where nature has run riot." "It's the jewel in Madagascar's crown." "Subtitles by Red Bee Media Ltd" "E-mail subtitling@bbc.co.uk"