Cryptozoology, the study of animals whose existence is unproven, lies just south of the boundary between science and pseudoscience. Unlike most psuedoscientific movements, which require adherents to suspend disbelief and ignore the realities of physics, chemistry, medicine, and, well, reality, the foundational principals of cryptozoology – that there are remnant populations of thought-to-be-extinct species and that there are still large, charismatic animals that have not yet been discovered – are grounded in ecology. In deep-sea biology, we discover new species all of the time, some of which are far more fantastical than humans can imagine. Some times, we even discover once extinct species. So it is not much of a leap to go from exploratory zoology to cryptozoology.

Where cryptozoology breaks down is in the specifics of each cryptid, especially the charismatic cryptids that occupy much of the cryptozoological discussions – stealthy hominids and various lake monsters come to mind. Bigfoot is the classic example of this problem. After 50+ years of bigfoot hunting, without progress, the “bigfoot community” is driven by a desired result, not a hypothesis. In science, you test a hypothesis and collect data that may confirm or reject that hypothesis. In pseudoscience, you begin with a desired result and then cherry-pick only the data that supports that result. Add to that a cottage industry built around manufacturing hoaxes, and you now have something dramatically different from conventional zoology.

While some branches of cryptozoology have drifted further into the realm of psuedoscience, others are just at the cusp of valid science. Perhaps the best recent case of this is the discovery of the giant manta ray. Last year, population geneticists revealed that there is a new, cryptic, species of manta ray that is slightly larger and more migratory than other manta species. Rumors of a giant manta had been told for generations, and the confirmation that there was a second species raises an interesting questions: What is the difference between cryptozoology and local knowledge?

Many, if not most cryptid rumors stem from reports by local residents. At some level, local reports of mysterious animals are simply the stories of people familiar with their home ecosystems. The discovery of dozens of new vertebrate species in Papua New Guinea last year is evidence of that, as is the revived hunt for the Ivory Billed Woodpecker in the southern United States. Are these cases of successful cryptozoological expeditions, or the discoveries of conventional zoology?

It doesn’t really matter. Cryptozoology has the dubious honor of being the one psuedoscience that can be driven by either an honest desire for discovery or by the cherry-picking and myth-mongering of it’s more disreputable ilk.

I love cryptozoology. As a kid, I used to eat up books and stories about mysterious creatures and cryptic rumors. The more detailed and convincing, the better. This, among other influences, is part of the reason I fell in love with deep-sea biology. Whether you’re searching for a Cadborosaurus swimming around Alaska or a bone-eating worm that colonizes the rotting corpse of a dead whale to extract lipids from a calcium matrix while harboring a parasitic dwarf male harem (and really, which one sounds more fantastical?), that drive to discover more about the world than was known before is there.

Can cryptozoologists be misguided? Of course. Is the field plagued by bad science, blurry pictures, and a lack of evidence? Absolutely. But unlike most other pseudosciences which encourage believers to abandon reason and accept irrational and unfounded explanations about how the universe works, cryptozoology encourages believers to keep exploring.

As long as you continue to ask questions and explore the natural world, there’s always a chance to discover truths in the tall grass or the deep sea.