Note: Science writer Brian Switek is the author of the critically acclaimed “Written in Stone: Evolution, the Fossil Record, and Our Place in Nature.” His new book, “My Beloved Brontosaurus: On the Road with Old Bones, New Science, and Our Favorite Dinosaurs,” will be published by Scientific American/Farrar, Straus and Giroux in April.

Jeff Meldrum wants to search for Bigfoot by using a remote-controlled blimp. Because when you’re looking for a mythical creature famous for eluding all who search for it, a giant, buzzing, looming balloon is clearly the way to go.

Meldrum, a tenured Idaho State University anthropologist who established his career studying primate foot anatomy before shifting his focus to monsters, expects he’ll have to raise $300,000 to get the project airborne. He’s trying (and so far failing) to get funding from private sources.

That’s a lot of money and effort for what will undoubtedly turn out to be a collection of blurry photographs that look like Instagram snapshots from a visit to the Pacific Northwest woods.

The picture historians and sociologists have pieced together is that Bigfoot and other shaggy humanoids are cultural inventions that we have repeatedly conjured so that there’s always something wild and mysterious in the woods.

No fossil record

The cryptozoological faithful are convinced that monstrous beings must be out there, just out of reach.

If you browse the Bigfoot Field Researchers Organization website, for example, you’ll find more excuses than hard evidence. Despite the ubiquity of smartphone cameras and the accessibility of camera traps, there are no clear photographs of the mythical ape.

The site asserts that sightings are fleeting because Sasquatches are smart enough to avoid unwanted pictures. As for the lack of a body or bones: “No serious work has ever been done to look for remains of surviving wood apes in areas where they are rumored to reside,” the BFRO website says.

If Bigfoot – also called Sasquatch – were real, there would be ways to detect the creature’s existence. For one thing, there would be a fossil record of large apes moving into North America, probably from Pleistocene Asia. But fossil nonhuman apes have never been found in North America.

Field biologists study elusive living species by using camera traps, analyzing genetic data from scat, and following footprints. There should be a wealth of compelling evidence from such sources – but all we have is an abundance of purported sightings.

Given the number that Sasquatch clubs busy themselves with, I should be able to look out my window each morning and see Sasquatch families raiding my trash cans for leftovers. Bigfoot aficionados protest that they have found tracks, hair and other evidence. But photos show nothing more than a lack of rational skepticism.

Other discoveries

There almost certainly are large, yet-unknown marine animals awaiting discovery. They just aren’t sea serpents.

Zoologists Michael Woodley, Darren Naish and Cameron McCormick pointed out that several charismatic aquatic animals were described relatively recently, including the megamouth shark (Megachasma pelagios) in 1983 and the lesser beaked whale (Mesoplodon peruvianus) in 1991.

In 2012, zoologist Kirsten Thompson and colleagues reported on two carcasses of the spade-toothed beaked whale (Mesoplodon traversii), a species named in 1872 but known only from skeletal fragments until now.

Using such recent finds and a statistical analysis of the record of discovery, Woodley, Naish and Hugh Shanahan argued that there may even be some unknown seal or sea lion species out there.

At least the sea allows large creatures ample room to hide. Terrestrial habitats are becoming more closed-in each day. There is no country for Bigfoot.

In 2010, University of Queensland scientists Diana Fisher and Simon Blomberg suggested that extinction is not as easy to detect as zoologists had thought. In a data set of 187 mammals once presumed to be extinct, about a third were rediscovered later.

The amount of time researchers spent looking for missing species made a big difference. One or two searches aren’t likely to find a rare species that still persists, the researchers found, but three to six searches tend to suffice.

Beyond 11 searches, the likelihood that a mammal species exists drops off dramatically.

Zoologists have repeatedly searched for the Yangtze River dolphin and the Tasmanian tiger without success, and given the trends Fisher and Blomberg described, we can be sadly confident that these mammals are extinct.

Likelihood defies odds

Now consider the number of expeditions – by amateurs and professionals alike – for Bigfoot. With so many people carrying out so many searches across the country, someone would have found definitive evidence by now.

Entomologist Jeff Lozier and colleagues went one better with a 2009 study that used Sasquatches to critique a kind of ecological analysis called niche modeling. Its premise is that observations of organisms in particular environments can predict other habitats where that same organism will be found or might move to in the face of human-driven climate change.

Lozier and co-authors took details of 551 supposed Bigfoot sightings recorded by the BFRO and, based on where the events occurred, predicted that Sasquatches should be a common presence from southern California through most of Washington state.

Perhaps unsurprisingly, “observed” and potential Sasquatch haunts were all in black bear habitat, the bears likely accounting for many sightings of something shaggy tromping through the forest.

There has never been a better time for biological explorers. In 2011, biologist Camilo Mora and co-authors estimated that there may be as many as 8.7 million eukaryotic species on the planet, and the vast majority of those – 86 percent of species on land and 91 percent of species in the seas – have not yet been described.

There are discoveries to be made and mysteries to be solved, but not of lake serpents and preternaturally hard-to-photograph ape-men. Every time a Sasquatch fanatic or cryptozoologically minded creationist wanders into the forest, they are only confirming the nonexistence of their quarry.