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The famous stone figures of Easter Island
BBC Two, Thursday 9 January 2003, 9pm
The Mystery of Easter Island
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The Mystery of Easter Island - transcript

NARRATOR (JOHN SHRAPNEL): To the people who live there it is Rapa Nui. To the rest of us it is Easter Island, one of the strangest and most haunting places on earth. Hundreds of giant, stone statues are a lasting testament to one of the most extraordinary civilisations the world has ever seen.

DR JO ANNE VAN TILBURG (University of California, Los Angeles): They have left an indelible mark not only on this island, but on our consciousness.

NARRATOR: But for years Easter Island baffled everyone who went there. Nobody could work out who had created this civilisation, how they came to build these remarkable statues and ultimately, what was their fate? Now at last modern science is beginning to solve the mystery of Easter Island. On 5 April, 1722 in the middle of the Pacific Ocean two worlds collided.

JO ANNE VAN TILBURG: It must have been to them a bolt out of the blue, it must have been to them like a spaceship landing in your backyard. I mean it was an incredible experience to stand, as they did, down there along the coast and see those three ships.

NARRATOR: A people who'd been cut off from the rest of the world for more than a millennium came face-to-face with the most advanced society of the age. It was Easter Day and so the visitors, who were Dutch explorers, named their new discovery Easter Island. But when the Dutch came ashore they got a shock. An island they thought was populated by just Stone Age people contained something else - hundreds of giant stone statues.

DR PAUL RAINBIRD (University of Wales, Lampeter): One of the first things they noticed was these large statues standing on platforms. They wondered how on earth these people had manufactured these, how they'd, they'd set these statues up. They, they hadn't encountered anything like this before and I suppose this was really the beginning of the European fascination with Easter Island and, and its mystery.

NARRATOR: The Dutch were dumbfounded. They couldn't see how the primitive islanders had made such huge statues. And there was more. The islanders had also created spectacular stone engravings of a strange creature, half-man/half-bird, and grotesque wooden carvings of people apparently starving. It was an encounter that would reverberate for hundreds of years and begin a mystery that has endured to this day. Because the great puzzle for anyone trying to find out what happened here is: there's no one to tell them about it.

Today about four thousand people live on Easter Island, but most have come recently from Chile and from the other islands of the Pacific, so they have no memory of the island's past. Only a few fragmentary legends survive from the time of the great statues. Which means the questions the Dutch asked all those years ago are still the same unanswered questions today.

PROF CHARLIE LOVE (Anthropologist): Who are the people who came to Easter Island?

PROF JOHN FLENLEY (Massey University, New Zealand): And how did they get there?

CHARLIE LOVE: Why did they carve big statues?

JO ANNE VAN TILBURG: What did the statues mean?

NARRATOR: And there was one other question, the question that was the most mysterious of all.

JOHN FLENLEY: Why did it all come to an end? What happened to destroy that civilisation?

NARRATOR: These then are the questions that have obsessed scientists for years. And now at last they're beginning to find the answers. The first, and most obvious, mystery is who were the original islanders? Where had the statue-makers come from?

PROF ERIKA HAGELBERG (University of Oslo): I think there's a genuine mystery on Easter Island. There's a, it's a tiny, tiny island in the middle of the Pacific Ocean. If you look at the map people could have come from either direction.

NARRATOR: Easter Island is the most remote inhabited island in the world. The nearest land is thousands of kilometres away - South America to the east and the scattered islands of Polynesia to the west. In the 1950s the famous explorer Thor Heyerdhal came up with his theory that the Easter Islanders had come from South America, the nearest large landmass. His kon-Tiki expedition showed how it was possible to sail a primitive raft across the Pacific from South America to Easter Island. But it was only a theory. Others thought the Easter Islanders had come from the opposite direction, from Polynesia. For years there was no way of telling which theory was right. And then along came Erika Hagelberg. She's a geneticist and it was genetics that held the key to the mystery.

ERIKA HAGELBERG: Essentially nobody had looked with modern genetic techniques and the ideas to be able to find out and to look directly at the genetic material of prehistoric people is terribly exciting prospect.

NARRATOR: Hagelberg set out to look for something called a genetic marker. People from different parts of the world have different genetic signatures that can help identify their origins. So she extracted DNA from the skeletons of early Easter Islanders, searching for the genetic marker that would finally identify who they were and where they'd come from. And at last she found the answer: a genetic marker called the Polynesian motif. It's unique to Polynesians.

ERIKA HAGELBERG: And that was an exhilarating finding. It was marvellous because it's, it's unambiguous, it shows that these people had to have been descendants of Polynesians.

NARRATOR: Finding the Polynesian motif proved that the Easter Islanders had come from Polynesia, not from South America. Hagelberg's discovery makes Easter Island the furthest outpost of the Polynesian people, perhaps the greatest seafarers the world has ever seen.

JO ANNE VAN TILBURG: Over 350 islands were discovered, colonised, settled by Polynesian people. It was a massive amount of watery miles that travelled under their hulls as they went from island to island. This is a remarkable achievement, this is an achievement that stands alone really, to my knowledge, in the history of the world.

NARRATOR: Carbon dating suggests the Polynesians reached Easter Island around AD700. But that was it. For the next one thousand years it seems that no more people came to Easter Island. They were on their own. Archaeologists have now built up a detailed picture of how this tiny settlement took off. They've discovered the islanders were soon thriving. There were the ruins of hundreds of houses. Farming flourished and so did fishing. The population may have reached more than 12,000, three times more than the island supports today.

And their success showed itself in the one thing that Easter Island would become famous for: the carving of giant stone statues. These statues have puzzled everyone who's seen them for the last three hundred years. How did a Stone Age people make them? How did they manage to move them across the island. And above all else, why were they carved? What did the statues mean? The first answers came at a place called Rano Raraku. It's the quarry where the statues were carved. There are more than three hundred statues still there in every stage of construction. And there are huge coffin-shaped holes high up in the cliffs where hundreds more have been removed. Armed with only stone chisels carving them must have taken years. And that was just the easy bit. Next, they had to be moved. And no one has spent more time trying to solve this problem that Charlie Love. First, they had to be lowered from the top of the quarry.

CHARLIE LOVE: This was intended to have a segment of a very large tree inserted into it with enough strength so passing a rope around the outside you could control the descent of a statue freed from the bedrock somewhere farther down in the quarry. This smooth place right here is probably where one of the ropes passed out and went down towards where the statues are.

NARRATOR: Once they were lowered down, the next stage was transporting them across the island.

CHARLIE LOVE: The amount of work necessary to carve one, the amount of work necessary to build a ceremonial platform is nothing compared to the amount of work to construct the roads and to move these colossal statues along them.

NARRATOR: And there's been no more fiery debate between archaeologists over the years than the question of how they did it.

JO ANNE VAN TILBURG: Logic dictates that they were moved in a horizontal position. That's the easiest, the safest way.

CHARLIE LOVE: I think they moved these colossal statues upright.

JO ANNE VAN TILBURG: The best way to move a figure is the way we did it.

CHARLIE LOVE: Legends say that they walked.

JO ANNE VAN TILBURG: I don't see anything within a Polynesian tradition that would have suggested large, heavy objects moving upright.

CHARLIE LOVE: Moving them upright I think was the answer.

NARRATOR: Whatever the truth, hundreds of statues were somehow moved around the island, up hills, down valleys, distances of up to ten miles. Some weighed more than 80 tons, twice as big as the biggest stones at Stonehenge. But the bigger mystery is what were the statues for? What did they represent? Theories abounded. They were gods. They were the last vestiges of a long-lost civilisation that had once ruled the Pacific. Some even thought they were inspired by aliens. It was an Easter Islander who made a breakthrough, because for years one of the few clues anyone had to go on was something from the local Rapa Nui language.

SERGIO RAPU (Archaeologist): The statues, or moai, we also call arena ora ata tepuna - the living face of our ancestors.

NARRATOR: For years the traditional name didn't make sense. Whoever these ancestors were they looked dead, not alive. But then Sergio found some strange fragments of coral.

SERGIO RAPU: We were not sure what they were. In fact we find a different form, different shapes. They were well preserved because it was covered with sand and when we put them together it shaped like this, so on the site none of us really know what it was.

NARRATOR: It was then that Sergio remembered something. The strange, concave holes in the eye sockets of the statues, or moai.

SERGIO RAPU: I remember the concavity and the very nice concavity of one moai that we have erected on the platform already. Then a simple association in a matter of a second led me to the conclusion at that very moment that these was the inlaid eyes of moai.

NARRATOR: Gone was the dead look. The eyes made the statues come alive.

SERGIO RAPU: When I look at these stone statues I get the image of somebody that is full of pride. They have the mouth firm, they have the nose elevated and when they look at you, the statues, they're not looking at your face, they're looking over your head, so it's the image of leaders. These statues became alive, living face of our ancestors.

NARRATOR: Scientists now believe the statues were part of the Polynesian tradition of ancestor worship, but on a scale far beyond anything that had been seen before. Each statue was different, raised up to immortalise a dead chief. High on their platforms they were halfway between the living and the gods. With their backs to the sea their task was to look out over the people to inspire and protect them. But then something went very wrong. The statues were pulled down.

CHARLIE LOVE: At some point in the history of Easter Island culture these statues that are on the platforms came tumbling down and when they did so it was terribly destructive. This one as you can see broke the neck, but they also destroyed other parts of the ceremonial platform, pulling it apart with a vengeance. This statue right here has its head completed snapped off and it's now missing, or this statue whose nose is down in the dirt. It didn't break when it fell, but it tells you that there had to have been some kind of violence involved. On this ceremonial platform alone there are 17 that have been turned over.

NARRATOR: The quarry where the statues were carved was also abandoned. Carbon dates suggest it had happened by the 1600s, a century before contact with the West. For some strange reason it seemed the people of Easter Island had turned on their gods. When scientists went in search of reasons all today's Easter Islanders could give them was a series of incoherent legends, of a time of terror, hardship, even cannibalism. But no one could tell them what had actually happened.

Then they discovered a new kind of stone implement: spear tips. These suddenly appeared in the 1600s, the same time the quarry was apparently abandoned. For some reason the Easter islanders were making weapons. Then scientists found out what those weapons were being used for. Doug Owsley studied the remains of more than six hundred Easter Island skeletons from the same period. What he found was shocking.

DR DOUG OWSLEY (Smithsonian Institution): This is an older female and she has in her frontal and adjacent parietal evidence of extensive injury. Would have died either from the problems that were caused with a brain injury, or very small blow that hit right here on the right parietal and so this is a person that's received a very serious blow to the right side of the head. The entire left side has been fractured.

NARRATOR: Owsley realised he was looking at the evidence of people at war with themselves.

DOUG OWSLEY: When I compare the frequency of injuries that I've observed in the Easter Island population with other collections that I've worked with it certainly shows the high end. It's the extreme. It was a period of disintegration, social disintegration and turmoil. You've got endemic warfare, it's chronic and they're slugging it out, there's no doubt about it.

NARRATOR: But why? What had caused this catastrophe? What had driven the islanders into civil war? It was Dave Steadman who found the first clue. He's an expert on the Easter Islanders' diet. After studying the leftover bones from their meals he noticed a puzzling change. To begin with there were thousands of bird bones.

DR DAVID STEADMAN (Florida Museum of Natural History): The bones we found ranged from things like this, this is a, a petrel that no longer occurs on the island. Here's a shearwater called a Christmas shearwater that no longer lives on Easter Island. Then this tiny bone, might be a little bit deceptive, but it's actually from a very large bird. This is a little skull fragment from an albatross and you can see here that albatross is quite a giant bird.

NARRATOR: It seems that when the Easter Islanders first arrived their new home was the biggest bird colony in the world and that meant the islanders had an abundant source of food. But it didn't stay that way. By the 1600s, when the statue quarry was abandoned, all those birds had disappeared.

DAVID STEADMAN: Almost all of these species of sea birds, these 25 or 30 species of sea birds that I've identified in the early sites, almost all those species are gone, so this big variety of sea birds that Easter Islanders could have plucked from burrows and all that, that food source is, is gone.

NARRATOR: It was the same story with fish. Once the islanders' diet was full of tuna, mackerel and also porpoises, but by the 1600s they'd gone too. The consequences appear to have been terrible. These carvings show emaciated figures, their ribs exposed. It seems starvation swept across Easter Island. And starvation may have led to something even worse.

SERGIO RAPU: Any little incident like stealing the food because the people was hungry will lead to revenge, war, destructions and ultimately cannibalism grow out of that context of conflict and scarcity as the ultimate need for food.

NARRATOR: It looked as if the collapse of the statue cult and the outbreak of war were caused by starvation. But now there was a new mystery. How had Easter Island gone from a land of plenty to an island so desperately short of food? At first scientists thought it may just have been the result of the population rising inexorably. They'd simply over-exploited resources, like the seas birds. But then they found evidence that there'd been something else, something so devastating that it would change Easter Island for ever, trapping the population in a terrible cycle of starvation and warfare.

When Westerners first arrived on Easter Island they noticed that there were no trees, yet almost every other island in the Pacific was covered in forest. An island without trees didn't make sense. How had the islanders moved their statues, how had they made canoes to catch fish? The solution to this riddle came from the bottom of a lake. For thousands of years layers of mud had been building up. Mixed up in the mud was pollen from the island's plants. It was this pollen that held the secret of Easter Island's past vegetation. The man who dug it up was John Flenley. To begin with he examined pollen from the most recent layers of mud.

JOHN FLENLEY: So we started analysing samples from the top downwards and the uppermost ones had just grass pollen, exactly what we'd expect because that's what dominates the island today.

NARRATOR: Grass pollen is very distinctive. It's round with a pore at one end surrounded by a ring.

JOHN FLENLEY: But then a little way down we started to find another kind of pollen grain, quite different in appearance.

NARRATOR: This pollen was elongated with a slit running all down its side. It was the pollen of a palm tree and there was so much of it Flenley realised that the island must once have been completely covered in palm trees. So what had happened to them? Again the clue was in the timing. The trees had disappeared at the very time the statues had been abandoned and warfare had begun. It was then that scientists began to put together an extraordinary theory. The cause of this great disaster had been the statues themselves.

JOHN FLENLEY: Imagine you're trying to move a statue weighting perhaps 50 tons or more. Now every time you move one like that you are going to cut down palm trees. It's absolutely inevitable.

NARRATOR: Archaeologists realised that over the years the statues became more elaborate and also bigger and bigger; so big that one unfinished statue is more than 60ft tall and weighs about 400 tons.

JOHN FLENLEY: The statues were getting bigger through time, the palm forest was getting successively depleted.

NARRATOR: It was as if statue building had become a competitive obsession with each tribe trying to outdo the others with ever more magnificent carvings.

JOHN FLENLEY: The impact on the palm forest must have been progressively more and more disastrous.

NARRATOR: Obsession became mania, a craving that required more and more trees to satisfy it.

DAVID STEADMAN: By the time palm trees got scarce on Easter Island everybody on the island knew that they were in trouble. They loved palm trees, that's what, how they made their good canoes, that's how they rolled their statues. No palm trees equals we can't move our statues anymore.

NARRATOR: But by now nothing could stop the frenzy of destruction.

JOHN FLENLEY: In the case of Easter Island it's a fairly small island. You could stand on the summit of Easter Island and see the whole place. The person who cut down the last tree must have known that it was the last tree, but they still cut it down. This is the most amazing example in the world of total deforestation by people.

NARRATOR: The effect was devastating. Without trees the rains would have washed away their precious soil. Crops would have failed. There was no wood for canoes, so no more fish. And no canoes also meant no escape. The Easter Islanders were trapped in a hell of their own making. So they turned on each other and the gods who'd failed them.

DAVID STEADMAN: Finally they just boxed themselves into a real corner where there wasn't much left to do except fight over what little, what little was left.

JOHN FLENLEY: My explanation for the collapse of the Easter Island civilisation is ecological disaster. That's to say everything went wrong with the ecology of the island and the reason for that was people. It was a man-made ecological disaster.

NARRATOR: Easter Island society, it seemed, had self-destructed. For many scientists the story of Easter Island's collapse was nothing less than a parable for the whole world.

JOHN FLENLEY: Easter Island is isolated in the Pacific, just as the Earth is isolated in space. They over-used what might have been renewable resources and the result was an ecological disaster which brought about the collapse of their civilisation. Is there not here a lesson for Planet Earth?

NARRATOR: Easter Island's fall came to be seen as a terrible ecological warning from history. But there was one nagging problem with the self-destruction theory, something that just didn't fit. Paul Rainbird has studied the journals kept by the Dutch sailors who arrived on Easter Island in 1722. This was one hundred years after the island had apparently descended into starvation and conflict, and yet there was absolutely no sign of crisis.

PAUL RAINBIRD: In Roggeveen's journals we find that this, this place isn't an impoverished place at all. He talks about fields of sweet potatoes, he talks about yams, he talks about field full of sugar-cane and he also talks of the people themselves. They were healthy, they were fit, there is no sign at all of the collapse we're supposed to have regarded to have happened and indeed if that collapse was through warfare there was also no sign whatsoever of war-like behaviour. Indeed he noted that there were no weapons to be seen.

NARRATOR: If Easter Island had completely self-destructed the Dutch should have encountered islanders who were desperate and starving. But they weren't. They were fit and healthy with food to spare. So by the time the Dutch appeared the crisis was over. Something must have pulled Easter Island society back from disaster. The key to the recovery lies at Orongo, a place poised between an extinct volcano on one side and the crashing sea on the other.

JO ANN VAN TILBURG: If we presume that the fallen statues are emblematic of some sort of a failure then this place has to speak to an attempt to try to find a new way out of a crisis situation.

NARRATOR: Here archaeologists found mysterious carvings dating from just after the ecological catastrophe: a strange figure, half bird/half human.

JO ANNE VAN TILBURG: One example of such a carving is this one. You can see the open, curved beak, a round eye, very prominent, head, here's the body, muscular legs, human-like feet, a muscular arm and a human-like hand.

NARRATOR: It was the Birdman, a representation of everything an island people trapped in their own hell could desire.

JO ANNE VAN TILBURG: Birds have freedom don't they, birds come and go, birds bring with them fish which provide food. I think the birds are significant on Easter Island for sacred reasons, for spiritual reasons, but also for very purely economic reasons.

NARRATOR: In fact The Birdman was based on one particular bird: the frigate bird. It's one of the great predators of the Pacific, capable of flying huge distances, an understandable totem for a people confined on a tiny island. Early records told how the cult of The Birdman had worked to save the islanders. At its heart was an annual ritual, a competition involving every tribe on the island. Its aim: to crown a new Birdman. Opposite the cliffs at Orongo is a cluster of rocks, home of some of the last surviving birds nesting at Easter Island. Every year each clan chief nominated a young champion.

JO ANNE VAN TILBURG: Those young men would descend this cliff, plunge into that water down there, swim for their lives approximately a mile out, the largest of those three small islets, and there await the coming of the birds.

NARRATOR: The champion's mission was to grab the first egg to be laid.

JO ANNE VAN TILBURG: When the first egg was found by one of those individuals he placed it in some sort of a woven basket that he could wear on his head for its protection and he would then plunge into the waters, which by the way are full of sharks most of the time, and swim back, ascend the cliff and present the egg to the person who had sponsored him.

NARRATOR: Whichever tribe won the race then its chief was crowned ~The Birdman. That tribe then won the first call on the island's diminishing resources for a year. It was an ingenious solution. The aggression that had once led to fighting had been turned into a harmless competition that led to an orderly parcelling out of food.

JO ANNE VAN TILBURG: Whatever resources there were here had to be controlled and had to be dis, dis, dispensed, if you will, among the population in an organised way, or people were going to start getting hurt and so I think this place represents an incredible societal effort to channel the aggression, control the competition and keep the society working.

NARRATOR: Historical accounts suggest the Birdman cult did bring some stability to the island. That's why when the Dutch arrived there was no sign of warfare and food seemed plentiful. The worst of the crisis was over. But if they recovered then what was it that eventually finished off Easter Island's civilisation? Easter Island's final nemesis came from far over the horizon, from a world that the islanders didn't even know existed. Until Easter Sunday 1722 that is. The collision between the modern world and Easter Island was devastating. The diaries of the Dutch captain showed that disaster struck almost immediately.

PAUL RAINBIRD: This is in minutes after arriving on the shore. There, there's panic. Easter Islanders are running everywhere. He immediately tries to find out what on earth's being going on and as he, when he finds out what's going on he finds 10 or maybe 12 Easter Islanders dead and many more wounded.

NARRATOR: On its own this savage introduction to Western civilisation needn't have been the end of Easter Island's Stone Age society. The trouble was it was only the beginning. Over the next hunded years things got relentlessly worse as more and more ships called in. And they brought with them something much more terrible than weapons: disease. Again and again in the bones he examined Doug Owsley saw the same thing.

DOUG OWSLEY: When we look at this shin bone, for instance, the curvature that occurs and the increased thickness, it's very different from what the normal form of the bone looks like If I compare it with this tibia for instance here which is straight in comparison with the curvature of this, this individual.

NARRATOR: This thickening and curvature of the bones is the mark of a particularly devastating disease, a disease that had never been seen on Easter Island before Western contact: syphilis.

PAUL RAINBIRD: In many ways it's, it's, it's doubly an impact because not only do you get death or infertility through venereal diseases that may be spread of whatever, you also get an impact on the society, a society that doesn't necessarily understand what's happening to them. This really was a germ warfare.

NARRATOR: Faced with disease and the cultural shock of Western contact, Easter Island's fragile recovery began to collapse. The people became weakened and the death toll started to mount. The first signs may have already been there when Captain Cook arrived 50 years after the Dutch.

PAUL RAINBIRD: Things seemed to have changed. He finds people themselves appear to be impoverished. He, he says they're some of the most impoverished people he's found in the Pacific in his travels.

NARRATOR: Weakened by disease, demoralised by contact with outsiders the final blow came in 1862. Slavers from Peru kidnapped 1,500 people, about one third of the population. Their fate was truly terrible. Slavery in South America killed almost all of them within a year. The survivors, just 15 of them, were returned to Easter Island. And they brought with them something truly deadly: smallpox.

PAUL RAINBIRD: The smallpox epidemic that ran through Easter Island after their arrival back was, once again, completely dev, devastating and, and by 1877 the population of Easter Island was down to something like 111 people.

NARRATOR: It became known as the Great Death. Explorers write that at this time the island was littered with bones, so many bodies it was impossible to bury them all. And so in just a few short years a whole civilisation was wiped out and with it went the extraordinary story of its great rise and fall. Against the guns, germs and steel of the modern world what chance did the Birdman stand?

JO ANNE VAN TILBURG: With Western contact came every single problem that was ever inflicted on any island society and it all happened here.

PAUL RAINBIRD: Whatever may have happened in the past on Easter Island, whatever the Islanders did to their island themselves it totally pales into insignificance compared to the impact that was going to come through Western contact.

NARRATOR: So what then can we learn from Easter Island? In part it's the story of a people who destroyed their own environment, a people driven mad by their obsession with statue building.

CHARLIE LOVE: I think Easter Island is a kind of grand experiment. It allowed scientists to ask a question they never thought we should ask and that is: what happens when you put a boatload of people on an island with finite resources? On Easter Island, the most isolated inhabited place on the planet, the end equilibrium was small scale warfare and cannibalism.

NARRATOR: But there is another way of looking at the story of Easter Island.

JO ANNE VAN TILBURG: They achieved enormous success, they faced adversity, they triumphed over adversity and in the end they did the very best they could with the tools at their disposal. It is to many a parable of disaster, but it's a, it's a hymn to the human spirit.

NARRATOR: In a way both versions are true. The rise and fall of one of the most amazing civilisations on Earth is a story of epic human achievement intermixed with terrible folly. It is, in other words, the story of the whole of human history.

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