There are hundreds of cryptids (or unconfirmed species) out there, but is there any evidence that these mysterious beasts could actually be lurking in the shadows of the world's forests and oceans, instead of just our minds?
While a lot of 'monsters' are the result of just a few freak sightings, some of them have a much richer mythology that has prompted many people to believe that there has to be something behind the numerous sightings.
But, what will you choose to believe? Let's examine some of the three best known cryptids and see whether you believe they are more monster than myth.
Tales of the secretive Chupacabra originated in Puerto Rico after a spate of livestock killings left handfuls of unfortunate sheep and goat left bled dry with mysterious circular 'bite marks.'
Although this beast was initially described as a reptilian creature the size of a small bear that had plumes of spikes along its back, it began to experience somewhat of an identity crisis when it was spotted in mainland America.
People on the mainland who who claim to have spotted the goat-sucking beast describe it as a hairless, wolf-like beast that shares the Puerto Rican incarnation's love of slaughtering sheep and goats.
A five-year investigation by Benjamin Radford claimed to prove that the woman who initially reported the Chupacabra in Puerto Rico borrowed her description from Sil in the movie Species, which she had seen before the sighting.
Radford believes continental American sightings may be coyotes, wolves, and stray dogs suffering from an extreme case of mange and are forced to attack defenceless farm animals due to their weakened state.
A claim that was inadvertently backed up by a woman in Texas who thought she had captured an infant Chupacabra that turned out to be a raccoon suffering from a skin disease that causes hair loss.
Despite the evidence proving the Chupacabra is probably nothing more than a case of mistaken identity and folklore, there is no ignoring the fact that there was a spate of livestock killings in Puerto Rico that displayed strange wounds and an apparent draining of blood.
In 1975 hundreds of animals in the small town of Moca were discovered with small circular holes all over their bodies, and while a Satanic cult was blamed for the killings, there has never been an adequate explanation of the spate of livestock deaths.
Do you believe in the Chupacabra?
Loch Ness Monster
The Scottish Loch Ness Monster is a cryptid with a long and elusive past. The first recorded sighting of a sea monster in the rivers surrounding the Loch (or lake, if you're not Scottish) occurred in the sixth century.
The creature was well and truly thrust into the public eye and imagination when a British surgeon named Dr. Wilson claimed he had snapped a photograph of the beast while he was overlooking the otherwise tranquil lake.
The iconic image of the head and neck of 'Nessie' emerging from the watery depths has been much disputed, with the Discovery channel claiming it was a small model being towed through the water in 1993.
Other Loch Ness Monster enthusiasts are adamant that the image cannot be a fake, with Tim Dinsdale, who wrote an entire book on the subject, citing the ripples as proof it really could have been a huge monster.
Popular myth claims that the Loch Less Monster is part of a breeding line of the last surviving Plesiosaurs that somehow found sanctuary in the lake, while all others of their kind perished.
Whether this beast is a myth or a monster is yet to be proven, but one thing's for sure, people just don't stop looking for Nessie.
In 2011 a fisherman named George Edwards came forward as one of the long line of Nessie spotters who claimed to have captured photographic evidence of the secretive underwater giant.
Despite the photographic evidence coming forward to this day, the BBC claims to have essentially disproven the myth with a sonar study in 2003. The extensive survey of the lake used 600 separate sonar beams and satellite tracking that could identify objects as small as a buoy, but no large creatures were found.
That didn't stop the Loch Ness Monster making a surprise appearance on Apple Maps on the 19th of April this year. This incarnation looks more like something akin to Whale Shark, so maybe there really is something out there after all...
Do you believe in the Loch Ness Monster?
Big Foot is probably the most well known cryptid, along with it's Himalayan cousin, the Yeti. The creature is described as a giant bipedal ape man who stands between 6.6 and 9.8 foot tall and weighs around 500 pounds. Witnesses also claim Big Foot has dark brown hair, a pronounced brow ridge and a deeply unpleasant stench.
Stories of Big Foot-like creatures have been circulating around indigenous populations on every continent around the world (except Antartica) for centuries, with one of the most famous stories being circulated by Reverend Elkanah Walker in 1840.
The Reverend recorded tales from the indigenous population around Washington that told of giants who skulked around the mountain stealing salmon from unsuspecting fisherman's nets.
Big Foot sightings really accelerated in earnest after unexplained footprints were discovered on two separate occasions in 1951 and 1958, but the most famous 'proof' of all could just be a hoax playing on public interest.
In 1967 Roger Patterson and Robert Gimlin claimed to have captured Bigfoot on camera while the beast was roaming through the forest in Bluff Creek in Oklahoma.
There has been much argument about whether the footage in genuine. Bernard Heuvelmans, the so-called 'father of cryptozoology,' claimed the creature's movements suggest it is a human in a suit, but other Anthropologists, such as Grover Krantz, are convinced the footage is real due to the 'realistic musculature.'
Patterson and Bluff were adamant that the Big Foot in the footage is real, despite others coming forward claiming to have made the suit and been the actor who played the gigantic ape.
Big Foot is very much still alive and well in the public imagination, and there have been plenty of alleged sightings in recent times. One of the most famous of the bunch is a 2007 shot of a 'juvenile Big Foot' from a trip activated camera belonging to a hunter named Rick Jacobs.
One of the most notorious cases in recent times was by the serial hoaxer, Rick Dyer, who claims to have obtained an authentic Big Foot carcass twice.
The first 'Big Foot' was taken on tour as a curiosity, but when it was examined it was revealed that the so called corpse was an Amalgamation of fake hair and rubber.
The second Big Foot, that Dyer claims to have shot himself in January 2014, hasn't been seen by the public yet, although Dyer claims that he has conducted scientific investigations:
From DNA tests to 3D optical scans to body scans. It is the real deal. It's Bigfoot and Bigfoot's here, and I shot it and now I'm proving it to the world
So far, none of the promised information has been released.