The Rare Creatures Committee hopes to change all that - with a little help from satellite orientation systems, night-scopes and luminous compasses. The group's headquarters is tucked away in a Beijing back alley, its entrance guarded by two crumbling dragons. Inside is a storeroom packed with lanterns, batteries and US-made oxygen masks. Amid another room's clutter sits Wang Fangchen, the committee's secretary general.

Mr Wang is a bit of a strange creature himself, a dishevelled academic type with eyebrows arched in a permanent quizzical expression. He once drove a homemade solar-powered car to work until the Beijing police forced him to dismantle it. Although his name-card lists him as a member of the Chinese UFO Committee, his current obsession is with close encounters of a hairier kind. For Mr Wang, wild man hunting is a serious scientific pursuit.

'We understand animals very well but ourselves very poorly,' he says, the bust of a wild man glaring over his shoulder. 'Finding the yeren will allow us to better understand man's evolution.' He believes the wild man is a direct descendant of gigantopithecus, an enormous primate that existed between 10 million and 600,000 years ago, and whose cousins include the American big foot, the Himalayan yeti, and other upright-walking monsters reportedly spotted in Russia, India, Mongolia and Australia.

The wild man is notoriously shy. He has never been photographed or filmed, and past hunts have turned up only inconclusive evidence of his existence: clumps of unidentifiable red hair, curious dung samples and footprints averaging 40 centimetres in length. The current yeren hunt - the biggest ever - will send 20-man teams into Shennongjia over the next year. Others will travel through the region's towns and villages to record eyewitness reports.

One of the first tasks is to decide what to call the yeren, which isn't as straightforward as it sounds. China's peasants have more than a hundred names for the beast in their midst, including 'man bear', 'savage animal', 'hairy thing', 'mighty man', 'monkey man' and 'mountain monster'.

Mr Wang prefers the more scientifically non-committal term qiyi dongwu - 'strange unknown creature'. He feels it's premature to ascribe human qualities to the animal. 'Before you can call the wild man human, you have to find evidence that he uses tools and language, and forms societies,' he said. 'At present, all we can say is that he's just a creature that walks upright.' If he's not extinct already. Mr Wang doesn't rule out this possibility. In recent decades the wild man's habitat has been squeezed by dam and factory construction, furious logging and by China's inexorable population growth. Ironically, though, this makes it easier for the yeren-hunters: they have fewer places to look. The creature is also thought unlikely to live at high altitudes, where there is little to eat.

Indeed, the way to a wild man is through his stomach. His diet, says Mr Wang, consists of berries, pine cones, honey, frogs, insects and rodents, although he has been known to steal rice from peasants in winter. 'His digestive system is poor,' says Mr Wang. 'He eats 40 kilograms of food daily, and 70 per cent is undigested. This means he doesn't travel very fast - he's too busy eating and excreting.' Even so, Mr Wang's hunt is no picnic. It is hampered by rough terrain, woefully inaccurate tranquiliser guns and an inadequate annual budget of $180,000. It also faces a rush of potential bounty hunters. Shennongjia's tourist officials have offered to pay $480,000 to anyone who brings them a live wild man, and $48,000 for a dead one.

Talk of bounty hunters is the only time Mr Wang's mask of scientific dispassion slips. 'The world has committed great sins against the air and the land and the sea,' he said. 'I don't want to commit any more. If we find a wild man, we won't hurt him or put him on display.' His arching eyebrows dip momentarily. 'And we'll shoot anyone who shoots him.' The history of the Chinese yeren stretches back for millennia. According to A Chronicle of Numerous Strange Things, written during the Tang dynasty (618-907), a wife who was abducted and raped by a wild man gave birth to two furry babies. Another ancient text relates how an emperor during the Song dynasty (960-1279) granted his pet yeren the title 'heavenly teacher and imperial protector' - an honour revoked when the beast snuck into the palace and 'violated the highest-ranking imperial concubine'.

Tales of abductions continue right up to modern times. In 1976, a woman vanished in Shennongjia's forests; she later reappeared, went mad, mumbled constantly about 'a very tall red man', then hanged herself.

A Shennongjia ranger's 1967 brush with a wild woman was less traumatic, at least for the ranger. One winter's day, he came across a red-haired animal with 'breasts the size of rice bowls and nipples the width of thumbs'. The creature embraced him and began rubbing herself amorously against his side. When he pulled away, she walked off, head hung and weeping. Or so the ranger says.

The first full-scale yeren hunt began in 1977. But the 140-day mission, with manpower supplied by the People's Liberation Army, only turned up more footprints and fur. Samples of wild man hair - which locals believe can staunch bleeding wounds - were sent to China's top institutions for DNA testing. Conclusion? 'The hair's elementary makeup resembles neither that of normal man, nor that of normal animal,' said one analyst. Other scientists claim that the samples were dyed red or plucked from the shoulder of a golden-haired monkey.

The launching off point for Shennongjia National Park is the city of Yichang, also the construction base for the colossal Three Gorges Dam. The dam's reservoir will eventually displace millions of people - including, fear Mr Wang and others, an unknown number of wild men.

From Yichang, the park is an eight-hour bus ride through a landscape of serried tea plantations and electric-green rice paddies. Much of Shennongjia is a closed area, as indicated by large, unfriendly roadside signs reading: 'Foreigners are forbidden to pass.' Shennongjia means 'Shennong's bridge'. Shennong is the founder of Chinese agriculture and medicine, who saved lives by making a bridge out of a tree to reach inaccessible herbs. Two-thirds of Shennongjia's tourists come to see the region's diverse wild life, the other third to meet the wild man. 'He's very friendly,' explained one local tour guide. 'He'll come up and grab your hand. Then he'll laugh and fall into a kind of faint. If you want to catch him, then that's your chance.' Outside Songbai, Shennongjia's biggest town, a sign marks the site of the 1993 'three wild men sighting'. This famous incident helps explain why China's scientific elite is now searching for a legendary ape-man. But first we need to go back to 1984, to a now infamous article in Beijing's Nature magazine entitled: 'Do wild men exist? I say no!' In it, a scientist called Tan Bangjie angrily wrote that the wild man issue 'sets my whole body aflame'. He declared that future missions should set out to disprove the wild man's existence, rather than prove it, since all scientists had to go on were testimonies from uneducated 'country bumpkins'. Fair point, many thought.

Then, in September 1993, 10 men in a minibus were trundling down a Shennongjia hill with the engine off to save petrol. Turning a corner, they saw three yeren walking up the hill on two legs - a large one with two offspring. The bus got within 20 metres before the driver shouted, 'look, wild men', and the startled creatures disappeared into the woods. The incident was important because the bus did not contain 'country bumpkins' or locals who might have something to gain from keeping the monkey man myth alive. These were educated men, mainly engineers, from another province, so their testimonies were widely believed. By helping to convert former yeren doubters into enthusiasts, the sighting was a significant factor in launching the current mission.

Zhang Jinxing is more than a convert. He's a fanatical yeren-hunter. When he's not hacking through Shennongjia's wilderness, he lives in a damp, unadorned room in a remote cluster of cottages - the base camp for the yeren hunt.

Apart from some road builders, two goats and a caged rat, 41-year-old Mr Zhang was alone. The first week-long expedition had already returned to Beijing - empty-handed - and another team had been dispatched. But Mr Zhang likes the solitary life. His slight frame is topped by immense shoulders, the result of lugging a 50-kilo backpack on solitary yeren forays. He carries no gun, just a small knife and a point-and-shoot camera.

'There's no danger, and I wouldn't care if there was,' he said, his nicotine-stained smile lost beneath a great hedge of beard. 'Anyway, we have nothing to fear. We're out there to protect the wild man.' The yeren couldn't wish for a more dedicated guardian. Mr Zhang has given up everything to join the mission, including his wife and family in distant Guangxi province. 'I won't return to them until I find the wild man,' he vows. And what if he never finds one? 'Then I'll never go back. You Westerners have all these luxuries, but I could give them all up for achieving this one goal. Finding a wild man is the only thing that matters.' It seems extraordinary that despite hundreds of alleged sightings of yeren in Shennongjia, nobody has ever caught one - dead or alive.

THAT is, unless you believe this tall tale. In 1942, locals were haunted by an inhuman cry emanating from a nearby mountain. So the county chief set off with 50 militiamen to investigate. In a forest clearing, they found a wild man sitting on a tree stump, bawling his heart out. On closer inspection, the county chief realised the yeren's testicles were wedged painfully into a crack in the wood. Then the chief shot him.

If the party had really found a yeren, you'd think they'd have kept the evidence. But no. They skinned it, cubed it, stewed it and ate it. A shaggy man story, perhaps? Many believe the yeren could be an elaborate hoax. Others argue that 900 million Chinese peasants have better things to do than play practical jokes. But that doesn't mean they're reliable. Mammoth footprints could be made by a bear, for instance. And gibbons, short-tailed macaques and golden-haired monkeys are all found in wild man territory, and could be mistaken for them.

As can man. During a China trip, a tall and hairy American anthropologist called Frank Poirier recalls local children fleeing from him with cries of: 'Wild man, wild man.' But, as the centuries have passed, an unstoppable momentum of yeren 'evidence' has gathered. In an area of Shennongjia called Bambiyan, there is a large sign which reads: 'We urge you to stay on the path and to leave the wild man's comfort and tranquility undisturbed.' It was near here, in the late 70s, that a Chinese journalist came across two curious structures. They consisted of 18, index-finger-thick sticks of bamboo intricately woven by someone (or something) with great dexterity and strength.

The journalist concluded he had found a yeren nest 'as comfortable as a springy deckchair', and many believed him. Others said it was a hoax - not because the yeren doesn't exist, but because everyone knows that he is a cave-dweller, like bears or early man. Everyone except for one Shennongjia Communist Party official, who claims to have seen a wild man sleeping in a tree.

SUCH eyewitness testimony is gathered in the Shennongjia's Wild Man Museum, which opened three years ago. 'Museum' is perhaps too grand a word for a converted cottage nestling in a leafy gully at the end of a dirt road. 'We'll take you into a mysterious world,' promised a sign stencilled on its wall. Unfortunately, someone had gone off with the key, so the mysterious world was closed for the day.

Hu Zhenlin is the museum's curator and a member of the latest wild man mission. Back in 1972, when Mr Hu was a lowly county surveyor, he found giant footprints stretching for 200 metres through the snow. The prints had no instep and were half as big again as his snow-boots. He had no idea what made the tracks until several years later, when he heard about a wild man expedition. He found more footprints in 1981 around his tent. 'I developed a sixth sense that night - the sense of the wild man in our midst,' he told reporters afterwards.

Now 72 years old, Mr Hu is a fully paid-up yeren hunter, as are his wife and son. Mr Hu believes the latest mission will succeed. He points out that the scientific world presumed the giant panda extinct, until they stopped digging up fossils and looked for the real thing.

The same will happen with gigantopithecus, he says, especially as its fossils are found in the same areas as the giant panda's. Many of Hu's more learned colleagues in Beijing share this reasoning.

Then again, many don't. Back at Beijing's Natural History Museum, a respected paleoanthropologist had already given his verdict: the hunt was doomed to fail.

When the Committee for Research of Strange and Rare Creatures launched its mission, it was meant as a sincere attempt to solve one of our planet's most enduring mysteries. But it will probably end up as just another huge, state-sponsored vote of confidence for several thousand years of myth and mouthwash.

One of the mission's avowed aims is to help eliminate false conceptions about the creature. Fat chance. Fact or fiction, the good folk of Shennongjia will always hold the wild man dear. They will keep taking money off tourists who come in search of him. They will always insist that his fur has healing powers. And - depending on who you believe - they will continue to spot him, track him and, on occasion, eat him.