I have what I think is a pretty logical and reasonable theory about Sasquatch sightings.  The thing about my theory is that it's plausible enough that any Sasquatch evidence is going to have to be able to definitely rule it out before it can be considered worthwhile.

In a nutshell my theory is: Crazy guy.

Crazy guys have been taking to the woods since time immemorial.  The tradition of the hermit is simply a crazy guy made canonical.  In modern times, crazy guys such as Ted Kaczynski have given the theory new life.

Picture a crazy guy.  He's wearing several layers of filthy clothing and animal skins.  He himself is filthy.  His hair hasn't been cut in years; it hangs in his face and drapes down his shoulders.  His beard is likewise voluminous and tatty.  He is barefoot, because his shoes rotted off years ago.  He smells very bad.  He - being crazy - wants you to get the hell out of his woods, so he throws rocks at your tent.  Maybe he leverages your Sasquatch fear by making loud hooting noises and screams.  Or maybe he's just talking Crazy Talk.  

Compare/contrast with Sasquatch sightings.  It's all there!  It all fits.

There are a lot of reasons why people ditch everything and take to the woods.  There are the Thoreau wannabes, like Christopher McCandless who famously starved to death in the Alaska bush country.  These eco-warriors develop a powerful relationship to the land, and can be very motivated to trick and scare "interlopers" like campers and hikers.

Another branch of Crazy Guys is your survivalist types.  These are guys who are borderline clinical paranoia cases.  They see ATF raids and black helicopters everywhere.  The gubbmint is out to get them, which leaves them no chance but to go on the run.  Live by their wits in the woods.  I imagine they spend a lot of time sharpening sticks and contemplating satellite imaging networks.

And finally, you have your genuinely crazy Crazy Guys.  Ever since Reagan emptied out our country's network of mental institutions, and the insurance companies effed over our coverage, it's become almost impossible for "edge cases" to get the mental health treatment that they desperately need.  If you are living in poverty without health insurance and you develop a severe case of psychosis or your schizophrenia runs out of control, then you my friend are out of luck.

Where religious hermits fall on this continuum, I leave as an exercise to the reader.  

Whatever the proximate cause, these hard-core mountain men have been tramping the woods since time immemorial.  Many researchers consider hermits to be the root source of many myths about trolls and other shaggy bogeymen.  And I strongly suspect that they continue to play that role, except that now we call them "Sasquatch" instead of "Green Man."

Given the distribution of Sasquatch sightings around the world, it seems unlikely that a species of very shy cryptid ape could account for all of them.  A breeding population that geographically diverse would surely be noticed.  However, individual Crazy Men could easily account for the distribution, and - sad to say - much more sensibly.

Creative Commons-licensed image courtesy of Flickr user treehouse1977