Yeti, Bigfoot, Sasquatch and Yowie - names that conjure up images of giant reclusive creatures that never quite stay still long enough for the photographer to focus their camera.

Over the years, hundreds of sightings of these supposedly mythical beasts have been recorded around the world by the public and so-called cryptozoologists, who scour the world in search of evidence for their existence. “Proof” comes in many forms, from fuzzy photographs and shaky videos to plaster casts of footprints and tufts of hair. But, as yet, none of these encounters has provided any conclusive evidence and cryptozoology remains a field largely disregarded by science. Instead, with a knowing look and a snigger, “sightings” of “cryptids” are explained away as hoaxes, existing species or the products of over excited imaginations.

So it makes it all the more extraordinary that established scientists would become involved in a search that, on the face of it, looks like it could help to prove whether or not these undocumented creatures exist. But, in May of this year, researchers from Switzerland and the UK did just that when they launched the Oxford-Lausanne Collateral Hominid Project.

“It’s one of the claims by cryptozoologists that science does not take them seriously. Well, this is their chance. We are calling for people to send us their evidence, and we will test it through DNA analysis,” says Bryan Sykes, a professor of human genetics at the University of Oxford in the UK.

It is likely that the project is the biggest and most comprehensive attempt yet to probe suspected “remains”. “Nothing like this, on this level, has been done before,” says Richard Freeman from the Centre for Fortean Zoology in the UK. But therein lies the rub. For people like Freeman who devote their lives to looking for these creatures, it is the biggest signal yet that after years out in the cold mainstream science is finally taking the seriously. But for some scientists, the whole venture is an embarrassing curiosity to be held at arm’s length.

Sykes is no stranger to media storms. As well as his work retrieving ancient DNA samples and mapping human migration through DNA analysis, he is also the founder of a business called Oxford Ancestors, which helps people trace their relatives through DNA for a fee. In 2003, the company claimed that an accountant from South Florida was a direct descendent of the Mongolian warlord Genghis Khan – something that sparked headlines around the world. Later analysis – and headlines –suggested that his company’s interpretation was incorrect.

Hair today...

If the episode scarred Sykes, it does not show. His new project was similarly announced to much fanfare, again sending headline writers into overdrive. “Scientists seek big genes of bigfoot”, read one. But the professor says that the response was to be expected. Myths and legends about these creatures loom large in every culture and the idea of finally finding solid evidence for their existence is appealing, no matter who you are. “It’s a story that just does not go away. We are so intrigued by these quests for the unknown, even doubters want to hear about developments,” he says.

For his own part, he says that he sees “no reason why there cannot be species not yet known to science”, but adds the caveat that he would “need to see the evidence”. He is also keen to point out that he is not – nor intends to become – a cryptozoologist. “I don’t not want to become completely eccentric,” he adds.

The idea for the project came about in 2011 when Sykes visited Dr Michel Sartori, the Director of the Museum of Zoology in Lausanne in Switzerland. Out of sheer curiosity, Sykes had gone to view the museum’s extensive library of books on cryptozoology, including over 40,000 documents and photos from a collection donated by the late Belgian-French scientist Bernard Heuvelmans. He was a trained zoologist, who also spent much of his life looking for cryptids. The museum holds many of his books, such as In the Wake of the Sea-Serpents, which records “sightings” of giant squids and whale-like animals.

During the visit, the pair began to wonder if they could build on Huevelmans’s work and expand the museum’s display. “We started to think it would really enhance the collection if we also had specimens of ‘cryptids’ on show,” says Sartori.

And so the Hominid project was born. The team has put a call out for people around the world to submit samples before September, along with theories about what they could be. They then plan to use DNA barcoding to test each specimen. It is a technique that is widely used in biology. For example it is used by food inspectors to check what is served up on a plate is what a restaurant says it is. Customs officials also use it to stop trafficking of illegal animal parts, whilst field biologists use it to identify organisms. In all cases the technique is largely the same. A sequence of DNA is extracted from an organism or sample of interest and then compared against a DNA bank.

In the case of the Collateral Hominid Project, the team will largely focus on hair samples – the most commonly presented physical evidence to back up claims of sightings.

“Up until the last couple of years, you needed quite a lot of biological material … and often the results were inconclusive,” said Sykes. “Now, all we need is a small amount of hair.”

Hair is useful because the keratin – a kind of biological plastic that encases the hair shaft - protects the DNA that it contains from the contamination and degradation that can affect DNA from other parts of the body, such as teeth and bone. Once they have extracted a sample, the will compare it to the billions of sequences published online, such as at Genbank (managed by the National Institutes of Health in the US). If the sequence is different to those known from existing species it may be a new species. The more DNA that is used, the more reliable the comparison.

‘Hidden from view’

But even if the team find a sequence of DNA that has no match in the world’s databases, it does not automatically mean that the creature is a mythical beast, says Albert Zink, an anthropologist at the European Academy of Bolzano in Italy, who questions the validity of the whole enterprise. “It could be a sample of an extinct animal that has nothing to do with the Yeti myth,” he explains.

Sykes admits that might be the case but he is unconcerned. Although the search for Yeti DNA grabbed the headlines, it is part of a bigger project charting the relationship between our own species and others. It could even help identify new species of hominid - a general term archaeologists and paleontologists use for humans and our ancestors. The team want to use the samples to narrow down their search for unknown species – alive or dead, mythical or not. If the DNA tests show something of interest, the thinking goes, the team can began to look for other clues – potentially in the area where the sample was found. Cryptids became involved because, along with unstudied primate species and subspecies of bears, some people believe the legends could describe distant relations.

"Theories as to what Yetis are... range from surviving collateral hominid species, such as Homo neanderthalensis or Homo floresiensis, to large primates like Gigantopithecus, which were widely thought to be extinct,” says Sykes.

These theories were given a boost in 2004 when scientists published details of skeletal remains of a species of human (Homo floresiensis) from the Indonesian island of Flores. The adult species, previously unknown to science, was just 1m (3ft) tall and was likely a descendent of Homo Erectus, which arrived on the island 900,000 years ago. As far as scientists can tell, the “hobbit”, as it was nicknamed, survived for thousands of years unnoticed by modern humans and was still alive as recently as 12,000 years.

Finds like this make it more likely that accounts of mythical, human-like creatures could be founded on grains of truth, some say. For example, the Indonesian cryptid Orang Pendek (“short person”) is often described in Indonesian folklore as a small, hairy, manlike creature not dissimilar to Homo floresiensis.

As Henry Gee, an editor at the respected Nature Journal, wrote in 2004 following the discovery: “In the light of the Flores skeleton, a recent initiative to scour central Sumatra for 'Orang Pendek' can be viewed in a more serious light.

He also argued that new species of mammal – including oxen - are still occasionally discovered by scientists. “If animals as large as oxen can remain hidden into an era when we would expect that scientists had rustled every tree and bush in search of new forms of life, there is no reason why the same should not apply to new species of large primate, including members of the human family,” he wrote.

Gee has since stepped away from the debate, but it’s a theory that others buy into. “Given how people are encroaching on wilderness areas, it seems increasingly unlikely that large mammals, and especially human-like species, remain undocumented,” says Dr Murray Cox from the Institute of Molecular BioSciences, Massey University in New Zealand. “However, some parts of the world, including the Himalayas and the arctic forests of North America, still show very limited impact by humans. So perhaps the possibility of new mammal species there cannot be completely discounted.”

‘Proper science’

But, others are less forgiving. According to Prof. Darren Curnoe of the School of Biological, Earth and Environmental Sciences at the University of New South Wales in Australia, the chances of finding a completely new species of hominid are remote. He is also critical of the project efforts, especially linking it to the possibility of finding a Yeti.

“There are far better ways to spend scarce funding for science than chasing mythological creatures and more than enough real and mind-boggling mysteries in nature to keep many generations of scientists busy,” he says.

Sykes has heard that kind of criticism ever since the project started. Although he admits that the project is speculative and unlikely to find a new species of hominid, he argues the search is still valid.

“Science does not accept or reject hypotheses but evaluates them on the basis of evidence,” he says. “This is why I am confident that examining the evidence of alleged Yetis does not fall outside the realm of proper scientific enquiry.”

And, of course, the project has captured the public’s imagination in a way that much of science does not. Put simply, the idea of a Yeti – or some other undocumented mythical beast from folklore – remains a seductive idea for humans. It taps into our desire to explore and understand the world around us, and to believe there are still things left to be discovered. It is part of the reason there was recently a team of 38 people tramping into the remote mountains of the Shennongjia nature reserve in Hubei, China, in search of the yeren. And part of the reason that countless teams over the last 100 years have probed forests, mountains, jungles and islands from the Himalayas to Borneo in search of them.

But the fate of these kind of expeditions – and the entire field of cryptozoology - could soon be decided by Sykes and his team. If the Oxford Lausanne project finds something interesting, it opens up the possibility of further attention from mainstream science. But another possibility is that the team races through all of the samples in the museum and proves that all of them come from species already known to science. Certainly history suggests this outcome is likely.

For example a “Yeti finger” that lay in the Royal College of Surgeons museum in London since the 1950s was tested in 2011, revealing that the remains were in fact human. While in 2008, tests on hairs collected in India showed they came from a species of Himalayan goat. Countless other examples have met with similar results.

If that is the case, the current saviour of cryptozoology could become its own worst enemy. And then, Sartori says, it will be time for believers to put up or shut up.

“We are challenging the people who claim to have seen the Yeti or the Orang Pendek to show us real evidence, or otherwise hold your peace,” he says.

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