Mount Shasta, California, 1963: A man falls off a bluff near Mount Shasta while deer hunting and is badly hurt. Authorities said the man claimed a nine-foot Bigfoot carried him two or three miles to safety.

Inyo National Forest, California, 1996: Early in the morning, women campers on East Lake report a dark, large, bipedal creature, eight to nine feet tall, moving swiftly on an upper ridge.

South shore of Loch Ness, Scotland, 1999: A group of six or seven people near Urquhart Castle claim to witness a head and neck rise from the water 200 yards from the south shore of the loch. They watch the black shape rise and disappear, only to reappear a few minutes later. One witness describes the head as being about 18 inches in height.

While most dismiss notions of a Bigfoot or Loch Ness monster as tall tales or hoaxes, there are those willing to examine such claims. A small but dedicated group, they seek the truth about these mysterious creatures and dozens of others. Some call them scientists, others call them obsessed, but these seekers believe in the virtue of the scientific method, even if their chosen field has a name that sounds like something from a comic book: cryptozoology.

Cryptozoology means, literally, the study of hidden animals. For many, this conjures up notions of eccentric old explorers in pith helmets spending their lives in remote jungles, camera in hand, desperately searching for traces of a beast from local folklore that's scaring away the natives. Yet there is a certain legitimacy to the field.

Although no universities grant degrees in cryptozoology, there are credentialed researchers who have hopes of tagging a cryptid, as cryptozoological specimens are known. The International Society of Cryptozoology (ISC) has more than 800 members, with a peer-reviewed research journal and a board of directors that includes tenured professors from universities around the world. The society was founded by Bernard Heuvelmans, a French zoologist who began the field of study in the 1950s and coined the term cryptozoology. ISC board member and journal editor Richard Greenwell has been on expeditions seeking cryptic animals on three continents. True cryptozoology, he insists, "does not violate any theory or principle of zoology or anthropology. We're not an advocacy organization. We have no agenda or axe to grind and make no claims that any of these animals exist at all."

Practitioners with backgrounds in paleontology, ecology, physical anthropology, and other fields have partially or completely turned from their original, mainstream scientific efforts to pursue dreams of discovering the one elusive creature that will turn biology on its ear. Many suffer ridicule and scorn from their colleagues, risking their credibility, careers, and livelihood by choosing a line of work considered by many to be scientifically unsound. "There tends to be an individual bias against what we do," says Greenwell, "but their attacks aren't scientific. A scientist should never say anything is impossible."

The Menagerie

Ellen Marsden, an aquatic ecologist at the University of Vermont, has experienced more than her share of local monster folklore. The bulk of her research takes place on Lake Champlain, where, legend has it, resides "Champ," a large reptilian creature similar to the Loch Ness monster. Lake biologists don't take these stories, or anyone who investigates them, very seriously, and often joke of making "Champ sightings" on hazy days when the lake is flat and the silent wakes of boats produce serpentine, humplike forms in the water. Yet Marsden says, "Lake Champlain was once connected to the ocean, and there is the possibility for large fish like sturgeon to be in the lake. The cool thing about fish is that they never stop growing; if one lived long enough it could reach a size of three meters. I'd have the willies looking at one of those things late at night."

Perhaps the most famous of all mysterious animals is the Loch Ness monster, or "Nessie." A local legend since the 6th century, the creature is supposedly very large and is often described as having a long neck and humped or ridged back. Many who follow Nessie speculate that it is a kind of plesiosaur, a marine reptile species from the age of dinosaurs, that somehow survived in the lake for millions of years. Although several photographs have been offered as proof of its existence, most have proved fraudulent, and little in the way of reliable evidence has been produced.

Thousands of miles away, in a remote swampy region of the Republic of Congo, native people speak of the monstrous "Mokele-mbembe." Reportedly the size of an elephant, it has a long neck and tail, with reddish-brown reptilian skin, and spends most of its time eating plants and living underwater. Some cryptozoologists have speculated that it may also be a prehistoric throwback, a kind of sauropod dinosaur like the famous brontosaurus.

In North America, tales have persisted for generations of Bigfoot, or Sasquatch as it is called by Native Americans. Reportedly a large, hairy, upright hominid, it is said to live in the remote woods of the Pacific Northwest. Tales exist of a similar beast, the yeren, that lives in the wilds of China. Cryptozoologists believe these may belong to a hominid species, Gigantopithecus, thought to be long extinct.


The Evidence

Why is it that despite the concentrated efforts of thousands to document the existence of these beings and many others, no solid evidence has been found? Although Loch Ness is relatively large in size, it has little flora or fauna, nowhere near enough to support a population of 30-foot aquatic reptiles. Furthermore, it seems unlikely that such a large reptile, which would have to regularly come to the surface to breathe, could go undocumented with so many eyes watching and cameras rolling. Meanwhile, the presence of ape-men, at least in North America, would defy the fossil record, which indicates that early humans, and all related hominid species, were confined to Africa, Europe, and Asia. In fact, there is no fossil evidence that higher primates existed at all in North America until the arrival of the first humans.

The theories put forward by some supporters for the existence of the creatures hardly represent legitimate scientific explanation. Suggestions that these creatures are inter-dimensional life forms, time travelers, guardian spirits, or similar beings help to drive any serious attempt to identify and document them into the fringe. Further undermining the search for substantive evidence are the many frauds and hoaxes that have been uncovered. Dozens of websites, magazines, and television programs are ready to lend fame to anyone who comes forward with a compelling story. Perhaps the most famous photo of Nessie, an early black-and-white image of a serpentine head emerging from the water, was later proven to be staged, as was some well-known film footage of a black Bigfoot-type creature walking though the woods. Other fraudulent photos, tracks, and testimonials lead the public to lump the entire topic of cryptozoology into the realm of the unbelievable, along with ghosts, UFOs, crop circles, and story lines straight out of The X-Files.

Cryptozoologists counter these arguments with an array of facts to support their cause. It was only quite recently, geologically speaking, that many large animals worthy of legend are thought to have become extinct. Up until the end of the most recent ice age, less than 10,000 years ago, dire wolves, woolly mammoths, and saber-toothed cats roamed the hills of California. It was less than 300 years ago that the 10-foot tall moa, a giant ostrichlike, flightless bird, disappeared from New Zealand. In Australia, the Tasmanian wolf, a large predatory marsupial, survived until the early 20th century. Sporadic findings of enormous fossil shark teeth in the depths of the tropical Pacific Ocean indicate a species of immense length, approaching 80 feet. One proposed source is the megalodon, a presumed-extinct species that would dwarf the largest modern predatory shark, the great white. Although commonly thought to have died out 1.5 million years ago, megalodon may have stuck around until much more recently, or perhaps even still exist. Extremely large cousins of modern crocodiles and pythons may also have lived until quite recently.

More compelling, if less intimidating, are recent well-documented discoveries of previously unknown living animals. The Chacoan peccary, the giant muntjac (barking deer), the megamouth shark, and the African okapi, which looks like an unusual cross between a giraffe and a zebra, are a few examples of large animals that somehow avoided detection until modern times.


The Hunt for the Truth

In truth, discoveries of new species are quite common. Despite some prevailing misconceptions, it is estimated that the majority of this planet's millions of life-forms have yet to be classified. Up until the 20th century, biologists spent much of their time documenting, cataloging, and classifying thousands of species of previously unrecorded plants and animals. The exploration of uncharted lands revealed an incredible array of wildlife unlike any ever known. Early descriptions of the kangaroo, giraffe, and gorilla were met with disbelief and scorn in European society. But as geographic frontiers vanished, the appearance of large new species became increasingly rare. In the early 19th century, no less an esteemed expert than the French zoologist Georges Cuvier determined that there were no new large animals to be found at all; only the small, timid, and remote remained to be discovered. Instead of comprising the bulk of zoological effort, the hunt for new animals became less and less productive.

Greenwell acknowledges that the odds that any directed scientific expedition would produce solid evidence are slim: "Most zoologists don't deal at the species level. Statistically, it just isn't productive." In spite of all their efforts, the members of the ISC have not made any breakthroughs beyond the first description of a previously unknown two-foot-long gecko, and that was found preserved in a museum. What was mainstream zoology now stands as a marginalized, if somewhat misunderstood, practice, considered by most to be unworthy of serious scientific effort. Yet strangely enough, the very thing that makes legendary animals unlikely, their large size, helps maintain public and professional interest in them. "Cyptozoology has the same problem as wildlife biology," says Marsden, "which is the allure of charismatic megafauna. No one cares about discovering a new two inch bat."

When cryptozoologists counter the skeptics with examples of recent discoveries, they also point out that there are still some places on Earth that are poorly understood. Of the world's ecological frontiers, one remains largely unexplored: the abyssal ocean depths. It is not surprising then that the two most celebrated cases of modern animal discoveries occurred in these dark, alien realms. For centuries, the legend of the kraken was only one of many unsubstantiated sailors' tales. Early whalers, finding enormous scars on the bodies of sperm whales, attributed them to a giant tentacled beast that dueled with the whales far below the water's surface. More recent evidence points to a very real culprit, the giant squid. Living at depths of 3,000 feet or deeper, this species is estimated to achieve lengths up to 65 feet. Their eyes alone are almost a foot in diameter, the largest of any known animal. In spite of its massive size, the giant squid's deep habitat makes it extremely difficult to study. Few specimens have been obtained, and no healthy living individual has ever been scientifically observed.

The most unlikely animal discovery of all occurred on the coast of Madagascar in 1938. At a local fish market, Marjorie Courtenay Latimer, a museum curator, noted a peculiar-looking fish nestled within the catch of a local trawler. The 5-foot-long black fish was identified as a coelacanth, a close cousin of the first fish to emerge from the water and evolve into all modern land vertebrates. These fish were thought to have gone extinct along with the dinosaurs, yet more than a dozen specimens have been caught since, and live video footage exists of several in the wild. The more recent discovery of an almost identical species off the coast of Indonesia, more than 6,000 miles away, indicates that coelacanths have a wider range than once believed.

The existence of these creatures provides the impetus for the ongoing efforts of researchers like Greenwell. The discovery of any one would validate the efforts of dozens of dedicated explorers, provide a wealth of scientific knowledge, and spawn a new wave of would-be cryptozoologists, eager to make history with even more amazing finds. Many scientists, even those skeptical of sightings and other claims, believe there is still much to be discovered. Marsden believes that "the chances are not that slim that eventually one of them will stumble across something new." Greenwell is preparing to lead a small group into the most remote parts of the Pacific Northwest in search of evidence of Bigfoot. Chronically short of funding but armed for the first time with state-of-the-art equipment, they remain hopeful a discovery can be made.

But the potential damage that could be done by such a discovery is disturbing. The scarcity of evidence for many of these creatures would indicate that if they exist their populations are quite small. The very drive to document, capture, and understand a Bigfoot or Nessie might threaten species that have clung to existence for millions of years. In fact, after the first coelacanth was discovered, the tremendous pressure to obtain additional specimens led to conservation concerns, and the very real threat of their extinction has spurred a concerted preservation effort. How ironic that a species that could survive through the cataclysmic death of the dinosaurs and 70 million years of environmental change might not be able to survive a single century of human curiosity. Perhaps some things are better left a mystery.

* originally published for Britannica.com in 1999