Christopher L. Murphy has written several books on the subject of Big Foot's existence.
He says sightings go back hundreds of years and thousands of reports have been logged. And although there are 'mountains of evidence' they're not yet enough to convince scientists.
He says a one-minute 16mm film taken in 1967 at Bluff Creek, California, (see above) provides some strong evidence.
The film (commonly known as the Patterson/Gimlin film) has been professionally analysed by a forensic examiner and could not be found to be a fake.
It was determined that the length of the creature's arms would be present in only one in 52.5 million people and the length of its legs in only one out of a 1,000 people.
Large human-like hand and footprints have also been found in remote wilderness. With the footprints an average of 15.6 inches long they are significantly different to a bear's paws. Characterisitcs suggest a primate of some sort, but the size and excessive weight to make them (depth of impressions) rule out humans.
What appear to be dermal ridges (like fingerprints) in the foot do not correspond to those of humans.
Preliminary DNA analysis from a blood sample - found on a trap set by hunters trying to catch the animal that was trashing their cabin - does not match neither human nor chimpanzee.