Horizon 39

Helike - The Real Atlantis (2002)

On a winter night in 373 BC, the classical Greek city of Helike was destroyed by a massive earthquake and tidal wave. The entire city and all its inhabitants were lost beneath the sea. What has bewitched archaeologists about Helike is that it was engulfed just when ancient Greece was reaching its height; when the philosophy and art that inspired the western world for thousands of years were invented. Its destruction was one of the most appalling tragedies of the classical world and most probably the reality behind the myth of Atlantis. But now, unlike Atlantis, a team of archaeologists may have found Helike - a lost city from the heyday of Greek civilisation. If it is as well preserved as everyone hopes, Helike could be a time capsule from this crucial time in human development. For centuries there had been just no sign of it. All archaeologists had to guide them were obscure and often contradictory ancient texts. So, despite numerous expeditions trawling the waters off the coast of Greece and vast amounts of money and technology thrown at the problem, no one could find anything except two small coins, unearthed over a hundred years ago. Then, in 1988 Dora Katsonopoulou and Steven Soter took up the challenge. Dora had grown up with the legend from childhood and was determined to find the archaeological treasure on her doorstep. Together they went back to basics and re-examined the ancient texts. These said that Helike had sunk into a poros, which everyone had taken to mean Gulf of Corinthe. But Dora thought that a poros could also be an inland lagoon. If she was right, the lost city which had inspired Atlantis might not be under the sea, as everyone thought, but somewhere inland. Studying the geology of the region, earthquake expert Iain Stewart argues that a large earthquake could well cause an inland lagoon. Small recent earthquakes in the region have caused ground liquefaction - a terrifying phenomenon where the ground literally turns to water beneath your feet. If the same had happened on a much larger scale then the whole city could have been plunged downwards, taking much of the city below sea level. But the earthquake in 373 BC could also have had a second more devastating effect. As well as liquifaction recent earthquakes have caused chunks of coastline to fall into the sea. If this happened on a large scale underwater landslides could cause a large wave, or tsunami. This would race across the Gulf of Corinthe, ricochet off the opposite bank and come charging back again, to crash over the sunken plain and fill in the lagoon. Dora's theory makes sense, except for one thing. There is no lagoon in the region today. There is, though, a trail of clues that explains what could have happened. An ancient bridge that is strangely nowhere near water shows how river sediment coming down from the mountains changes the shape of the plain - over hundreds of years the lagoon would have silted up, hiding the lost city beneath solid ground. A host of boreholes drilled into the plain and a remote cave with the legend attached to it have helped pinpoint where the now underground city might lie. Slowly Dora and Steven have pieced it all together, but there have been several false starts along the way. The first lot of ruins they found were Roman - a settlement built hundreds of years after Helike's disappearance to honour the famous lost city. Next they found ruins that turned out to be prehistoric - an early bronze age settlement built 2,500 years before Helike. It wasn't until 2001 that Dora and Steven at last got their breakthrough. Whilst Horizon was filming, the team uncovered ruins from classical Greece. Securely dated by coins and pottery, the team are convinced they have at last found the city they've been looking for. It will take years to uncover Helike's riches, but for the first time in thousands of years, we have glimpses of the lost city that inspired Atlantis.

Volcano Hell (2002)

It began with a ghastly tragedy. In 1985 the massive Colombian volcano Nevado del Ruiz erupted, melting a glacier and sending a vast landslide of mud down on the people asleep in the town of Armero below. Twenty thousand died. In the aftermath science was set a challenge: to make sure such a catastrophe never happened again, by finding a way of accurately predicting when a volcano will erupt. Now, at last, it seems that one scientist may have met that challenge. Anyone can tell when a volcano becomes active. You can see it and you can smell it. But a volcano can be active for years without erupting. For those living nearby, there is no way they will abandon their homes and livelihoods just because of a few rumblings. The only way to persuade them to seek safety is to predict an eruption almost to the day, leaving just enough time for an evacuation. Scientists threw themselves at the problem, but there just seemed to be no way to make sense of the violent forces at work inside a volcano. Then along came Bernard Chouet. He is different from other volcanologists. His training lay in the complex equations and theories of physics, and he believed the answer had to lie in analysing the mysterious patterns drawn by seismographs. These measure the tremors caused by active volcanoes. Previous attempts to use these tremors to predict eruptions had proved fruitless. No one could find any correlation between the squiggles on the graph paper and the timing of eruptions. So Chouet locked himself away for five years and then emerged claiming he had found the answer. The key, he said, were seismic signals called long period events. These strange shapes had baffled volcanologists for years. Chouet said they were made by molten magma resonating - that is coming under pressure - inside the volcano. The more long period events there were, then the nearer the volcano was to exploding. Chouet could use the long period events to predict an eruption to within days. But another scientist was working on a completely different method. Stanley Williams could not be more different from Chouet. Where Chouet crunched numbers and looked at graphs, Williams climbed into craters and got up close; because he believed the best clue to when a volcano would erupt was to measure how much gas it was belching out. In 1993 the two methods came head to head. A conference was held at the foot of another Colombian volcano, Galeras. The highlight was to be a trip into the crater. Williams's gas readings indicated the volcano was safe. Chouet's long period events suggested the volcano might blow. After some debate, Williams led a team of volcanologists up the mountain. Suddenly Galeras exploded, killing six scientists and three tourists. Williams himself survived but was maimed for life. Since that day on Galeras, Chouet's methods have commanded wide respect and have been increasingly used around the world. In a dramatic demonstration last year Mexican scientists used Chouet's method to predict an eruption of the mighty volcano Popocatepetl. Tens of thousands of people were safely evacuated just before the biggest eruption of the volcano for a thousand years. No one was hurt.

Fatbusters (2002)

There is a new epidemic sweeping the world. It's been silently growing over the last few decades - only now is it reaching dramatic proportions. If current trends continue, more than one quarter of British adults will have this disease by the year 2010. This new epidemic is obesity. Scientists have recently made significant discoveries, which could lead to a drug treatment for obesity. In the meantime, until the drugs are developed, what should we do to keep off the pounds? One thing is certain. Willpower alone won't stop the epidemic of obesity; however, new research suggests there may be an easier way to fight the flab than joining the gym. Meet the Padded Lilies, a troupe of obese water ballet dancers who insist it is impossible to change our natural weight. They say they are born with a slow metabolic rate that has made them fat. But scientists now know that fat people actually have a faster metabolic rate. The Padded Lilies' suspicion that there is something wrong with their biology may well be true... but not in the way they thought. In 1994, research into a fat mouse was the starting point for a revolution in the science of obesity. The obese mouse was missing a hormone called leptin, which turns off the feelings of hunger. Wall Street went mad and the patent for leptin was purchased by a biotechnology company for millions of dollars. It seemed that at last a quick fix for obesity had been found. However, researchers quickly discovered that fat people had lots of leptin. There seemed to be no connection between the fat mice and obesity in humans. Then four years ago at Cambridge University, a young researcher, examined the blood of two young children who were so obese they could hardly walk and were confined to wheelchairs. She discovered these children, just like the mouse, didn't have the genetic information to make leptin and so could not suppress their appetites. She had for the first time ever identified human beings who were obese because of a genetic error and not because they didn't have the willpower to control their desire for food. In the last few years, research into obesity has snowballed and scientists around the world have begun to explore the area of genetic human obesity. Dr John Clapham is tackling the problem of obesity from another angle, by speeding up metabolism. Based in a top secret lab he has genetically manipulated a mouse that we all want to be. It can eat huge amounts of food yet, because it has an unnaturally high metabolism, it can't put on weight. This cutting edge science could lead to another target for the battle against obesity. However, we don't yet have this miracle treatment, so what can we do in the meantime? Dr James Levine has come up with an extraordinary idea. His study suggests there may be a way to shed those pounds without taking drugs or even joining a gym. He has found that people who fidget find it very difficult to put on weight. So we don't necessarily need exercise, we simply need to up the pace of our lives; walk rather than drive, climb the stairs rather than take the lift, don't sit still: fidget. All this should help us keep the calories at bay.

The Lost Pyramids of Caral (2002)

The magnificent ancient city of pyramids at Caral in Peru hit the headlines in 2001. The site is a thousand years older than the earliest known civilisation in the Americas and, at 2,627 BC, is as old as the pyramids of Egypt. Many now believe it is the fabled missing link of archaeology - a 'mother city'. If so, then these extraordinary findings could finally answer one of the great questions of archaeology: why did humans become civilised? For over a century, archaeologists have been searching for what they call a mother city. Civilisation began in only six areas of the world: Egypt, Mesopotamia, India, China, Peru and Central America. In each of these regions people moved from small family units to build cities of thousands of people. They crossed the historic divide, one of the great moments in human history. Why? To find the answer archaeologists needed to find a mother city - the first stage of city-building. They couldn't find one anywhere. Everywhere this first stage seemed destroyed or built over. And so, instead, scientists developed a number of theories. Some said it was because of the development of trade, others that it was irrigation. Some even today believe it was all because of aliens. Gradually an uneasy consensus emerged. The key force common to all civilisations was warfare. The theory was that only the fear of war could motivate people to give up the simple life and form complex societies. To prove it, archaeologists still had to find a city from that very first stage of civilisation. If it showed signs of warfare, then the theory had to be true. When archaeologist Ruth Shady discovered her 5,000 year old city of pyramids in the Peruvian desert, all eyes were on the New World. Ruth's extraordinary city, known as Caral, is so much older than anything else in South America that it is a clear candidate to be the mother city. It also is in pristine condition. Nothing has been built on it at all. Instead laid out before the world is an elaborate complex of pyramids, temples, an amphitheatre and ordinary houses. Crucially, there is not the faintest trace of warfare at Caral; no battlements, no weapons, no mutilated bodies. Instead, Ruth's findings suggest it was a gentle society, built on commerce and pleasure. In one of the pyramids they uncovered beautiful flutes made from condor and pelican bones. They have also found evidence of a culture that took drugs and perhaps aphrodisiacs. Most stunning of all, they have found the remains of a baby, lovingly wrapped and buried with a precious necklace made of stone beads.

Death of the Iceman (2002)

In September 1991 two hikers made a sensational discovery - a frozen body high in the mountains, near the border between Austria and Italy. It turned out to be 5,300 years old, the oldest frozen mummy ever found. Named Ötzi the Iceman after the Ötztal area where he was found, he became a worldwide sensation. The body was taken to Austria where scientists soon got to work on him. They analysed his bone density to find out how old he was (in his 40s, an advanced age for the time) and examined his wonderfully preserved belongings. The cause of his death remained a mystery. Now archaeologists are being joined by forensic scientists to investigate this unique case and new research has revealed a shocking answer. The investigation into Ötzi's death started at the scene of discovery. By examining photos which had been taken at the site, Austrian archaeologist Konrad Spindler worked out the layout. He was particularly intrigued by the position of the Iceman's copper axe, which was found propped up against a rock. He believed that this must have been placed in that position by Ötzi himself which meant that everything at the site had been preserved in the position it was when Ötzi died. His body was slumped face down on the ground, his cap lay nearby just as if it had fallen from his head. Scientists also wanted to know when he died so they examined the ice in which he'd been found. This contained pollen that they could identify as coming from autumn-flowering plants, so they concluded that Ötzi had died in the autumn. Together, this evidence implied that the Iceman might have got caught in a storm and died of hypothermia. Then the scientists looked inside the iceman using X-rays and CAT (Computer Assisted Tomography) scans. They saw what looked like unhealed rib fractures. So Spindler came up with what he called his disaster theory. He believed Ötzi was a shepherd who, one autumn, was returning to his home village with his animals. When he got there he became involved in some kind of argument or battle. He suffered a severe injury to his chest, fracturing his ribs, but managed to escape. He fled into the mountains and made it to the top, but by then he was exhausted from his injuries. He lay down to rest in a sheltered gully where he died of hypothermia and was buried in ice. The theory seemed to make sense, but it would not go unchallenged for long. In 1998, Ötzi was transferred to Italy since the body had actually been found just inside the Italian border. There the iceman was placed on display in a specially built museum in the town of Bolzano. To put the finishing touch to their display, the museum contacted forensic pathologist Peter Vanezis to reconstruct Ötzi's face, based on the shape of the skull. Vanezis normally works from the skull itself, but in this case, of course, that was impossible. So using the 3D CAT scan data and a rapid prototyping machine, the Austrian team created a detailed life-size replica of the Iceman's skull and gave this to Vanezis. He then used a laser to scan the skull into his facial reconstruction system. This measures the proportions of the skull and shapes a generic face to match. This allowed him to recreate Ötzi's face at last. Vanezis also wanted to look again at the theory of Ötzi's death, to question assumptions that the archaeologists had made. More and more evidence was questioning the disaster theory. An examination of the contents of Ötzi's intestine found hop hornbeam pollen. This pollen was incredibly well preserved - the cell contents still intact. This could only mean that it had been consumed very soon after the flowering of the plant just before the Iceman died. And since the hop hornbeam only flowers between March and June he must have actually died in spring. Also, evidence from the body and objects showed that the site had melted at least once and so things weren't necessarily in the same position. And finally, new examinations of the ribs showed that they hadn't been fractured before death - but been bent out of shape after death. Scientists seemed to be back to square one. IIt seemed his death might be shrouded in mystery forever. Then in June 2001, his new custodians, the Italians, decided to X-ray the body again. A local hospital radiologist noticed what looked like a foreign object near the shoulder, a shadow in the shape of an arrow. When they looked at its density they found it was denser than bone, it was the same density as flint. They'd discovered a stone arrowhead embedded in Ötzi's shoulder, which had been missed despite 10 years of intensive study. Now scientists can tell a new story of the Iceman's death. Ötzi was attacked and managed to flee. As he ran he was shot in the back with an arrow. He pulled out the arrow shaft but the head remained stuck in his shoulder. He reached the top of the mountains but was now exhausted and weakened from bleeding. He could go no further, lay down and died. Although this story fits the latest results, there are still many unanswered questions. Scientists hope soon to conduct an autopsy to remove the arrowhead and only then will we be able to say for certain what killed Ötzi. The Iceman may still be hiding more secrets.