New DNA research may have finally solved the mystery of the yeti.
Tests on hair samples were found to have a genetic match with an ancient polar bear, with scientists believing there could be a sub species of brown bear in the High Himalayas that has been mistaken for the mythical beast.
Yetis, also known as the "Abominable Snowman" or "Bigfoot", have been recorded for centuries in the Himalayas, with local people and mountaineers claiming to have come face-to-face with hairy, ape-like creatures.
Bryan Sykes, professor of human genetics at the Oxford University, set out to collect and test "yeti" hair samples to find out which species they came from. In particular he analysed hairs from two unknown animals, one found in the Western Himalayan region of Ladakh and the other from Bhutan, 800 miles to the east.
After subjecting the hairs to the most advanced DNA tests available and comparing the results to other animals' genomes stored on the GenBank database, Professor Sykes found that he had a 100% match with a sample from an ancient polar bear jawbone found in Svalbard, Norway, that dates back at least 40,000 years - and probably around 120,000 years - a time when the polar bear and closely related brown bear were separating as different species.
Professor Sykes believes that the most likely explanation is that the animals are hybrids - crosses between polar bears and brown bears. The species are closely related and are known to interbreed where their territories overlap.
The professor said: "This is an exciting and completely unexpected result that gave us all a surprise. There's more work to be done on interpreting the results. I don't think it means there are ancient polar bears wandering around the Himalayas.
"But we can speculate on what the possible explanation might be. It could mean there is a sub species of brown bear in the High Himalayas descended from the bear that was the ancestor of the polar bear. Or it could mean there has been more recent hybridisation between the brown bear and the descendent of the ancient polar bear."
A photograph of a "yeti' footprint, taken by British climber Eric Shipton at the base of Everest, sparked global mania after it was taken in 1951.
Legendary mountaineer Reinhold Messner, who became the first man to climb Everest without oxygen, has studied yetis since he had a terrifying encounter with a mysterious creature in Tibet in 1986.
His own research backs up the Prof Sykes' theory. H e uncovered an image in a 300-year-old Tibetan manuscript of a "Chemo" - another local name for the yeti, with text alongside it which was translated to read: "The yeti is a variety of bear living in inhospitable mountainous areas."
Prof Sykes added: " Bigfootologists and other enthusiasts seem to think that they've been rejected by science. Science doesn't accept or reject anything, all it does is examine the evidence and that is what I'm doing."
His investigations features in a new three-part Channel 4 documentary series, Bigfoot Files, which starts on Sunday.
A book by Prof Sykes about his research, The Yeti Enigma: A DNA Detective Story, is to be published next spring.