A Critical Thought: Bigfoot

Riley Sproul A Critical Thought, Ideas Leave a Comment


This week I’m reviewing the claims of/for Bigfoot (or variations there upon). As specific videos, pictures, and theories are in rather large numbers, I’ll mainly be addressing what I’ve found to be the best arguments for and against Bigfoot’s existence. Let’s dive in!


Argument for:

The shear preponderance of sightings, from all over the world, is quite significant. From modern amateur photographs to what is often thought of as the epicenter of Bigfoot evidence, the Patterson-Gimlin (PG) footage. What’s more, the sightings are remarkably consistent with each other. All describing an ape-like creature, walking on two legs, covered in fur/hair. Much of the behavioral patterns are also the same; often territorial, vocal when provoked, and some claim crude tee-pee like structures are commonly built to signify territory boundaries.

There is a cross-cultural concept of Bigfoot-type creatures, from the North American Bigfoot to the Vietnamese Batutut. While some say these are different creatures entirely, the argument could be made that they are the same creature seen through different cultural lenses. This would account for the differences in description, and show just how wide spread Bigfoot-type beings are.

The PG footage, as mentioned above, is very much the core of several Bigfoot theories. It’s been analyzed by video professionals, Bigfoot enthusiasts, and evolutionary biologist alike. It is often considered the go-to resource for Bigfoot morphology and behavior patterns.

Bigfoot even helps fill out a potential “missing link” in the evolutionary chain from apes to homosapiens. Whether it’s a direct descendant or an evolutionary off-shoot, is very much in debate. But, if properly studied, Bigfoot could give us answers to our own history, not unlike the revolutionary find Lucy.

There’re no doubt that not all of the Bigfoot sightings are legitimate, and there are certainly hoaxes out there. But given the shear number of sightings, they can’t all be tricks of the eye or simple lies. Right?

Here are a few pro-Bigfoot sites where you can read more:

Tracking Bigfoot sightings.

Various Bigfoot phenomena.

Explanations of the Bigfoot story.


Argument against:

Starting from a place of no assumptions, let’s ask what we would expect to see if a population of Bigfoot were surviving on their own?

Firstly, there is a major misunderstanding of how big a “viable population” is. In order for a species to keep on keepin’ on, it needs a wide range of genetic diversity; otherwise you’ll eventually only have inbred individuals who accumulate so many DNA mutations, that they can no longer function or reproduce. So what is the smallest a population can be while still remaining viable?

Assuming humans and Bigfoot can be compared in this way, (and given their implied genetic heritage, they most certainly can) we can use human populations as a model. The smallest a human population can be, while maintaining genetic diversity is around 160. And this number is when they mate, not according to animal instincts, but to a strict breeding program (along with possible genetic modifcation). To engineer such a program, one needs significant technological advances. So to allow for the animal instinct of Bigfeet, the lack of a breeding plan, and the primate propensity for monogamy, let’s take that number to 1,900; which is being quite generous. (How’d I get that number?) And that’s the absolute minimum number, that would have to be near enough to mate, not the total world/country-wide.

Next, we would expect to see structures. Foxes and wolves make dens, beavers make quite substantial damns, chimps make nest/bed type shelters, ect. Any large population will leave obvious physical changes to its environment, especially one as evolutionarily developed as Bigfoot. Perhaps not log cabins, lean-tos, or livable tee-pees, but some effect would be left on the environment. And with around 1,900 individuals, it would be quite a substantial effect indeed. There have yet to any proven Bigfoot “nesting sites” ever found. The alleged tee-pee like territory markers, could easily be explained by trees falling in seemingly strange ways. Without a firm belief in Bigfoot, there’s no reason to assume that an apparent oddity to trees falling is anything other than just that… an odd falling of trees.

So where are these major signs of a viable Bigfoot population? While videos and pictures are commonly sighted as evidence, they simply aren’t everything we would expect.

If such a population was nomadic, perhaps minimizing the need for structures, local food supplies (for other native animals) would plummet when they came to town. The carcasses of whatever animals eaten, would hold innumerable tooth marks, possibly left behind hair/fur, or even signs of tool/weapon use. If they’re an omnivorous species, they would either leave dozens of stripped trees/bushes (if nomadic), or need to develop agriculture (if settled), perhaps the most noticeable structure one could make.

What we would expect to see, is something like the case of these animals (Cryptids That Turned Out To Be Real- Skeptoid Podcast #461 (15 minutes) –Read– or –Listen), where creatures once thought to be mythical were shown to be real through rigorous evidence.

In addition, (and this is also true for UFO sightings) as our cameras get more and more numerous, and more and more advanced, pictures and videos of Bigfoot still remain blurry, out of focus, and otherwise limited. Outlines are even drawn on suspected Sasquatches so as to make them visible to the audience.

A phenomenon that can explain a wide number of the picture, videos, and sightings, is called pareidolia. To summarize it, our brains evolved to see faces and familiar things where they don’t actually exist. Here (1, 2, 3) are some excellent examples of pareidolia.

Which leads one to ask, if that’s the reason for some of the videos, pictures, and sightings, what are the reasons for all the others? They can’t all be fake can they?

Well… Yes they can. This is actually a variation of the Argument From Popularity (or Argumentum ad populum). Through a variety of intentional hoaxing, pareidolia, confusion with other animals, and other established phenomenon; anything short of a body examined by numerous reliable medical professionals, can be explained more believably (and simply as per Occam’s razor) than inventing a new species. I say “inventing” because remember, we’re starting from a non-assumptive place.

As this section is getting rather long, I’ll defend against my own Gish Gallop by linking to some explanations of other Bigfoot claims:

What about foot prints? (scroll to the Bigfoot Prints and Casts section)

What about Bigfoot hair samples?

A list of disproven videos/pictures. (including the PG footage)



I came at this topic, expecting to wrap my mind around the ‘Bigfoot claim’ with relative ease. But I was surprised to find much of the Bigfoot believing community is at odds with itself. Many hold the PG footage as a crowing glory; others understand it’s a hoax, but easily accept even less substantial evidence. At this point, it would be amazing if Bigfoot (or some variation there upon) were shown to be real. But as the claim is often Unfalsifiable, and you can never prove a negative, the claim can’t be shown to be untrue beyond a doubt.

Basically; If you already believe, there are dozens of ways to convince yourself. But if you start with no assumptions, treating all things equally skeptically, the evidence simply doesn’t suffice.

After years of self professed Bigfoot experts hunting all across the globe, no one has turned up a body (there was a body hoax however). We’ve actually found more evidence for hundreds of species that went extinct millions of years ago, than has been found for Bigfoot.

At the end of the day; extraordinary claims, require extraordinary evidence. And the evidence to date, just isn’t up to the task.














Riley Sproul has a Bachelors in Biology, with a concentration in PreMed, and a Chemistry Minor, from the University of Toledo. His goal is to obtain a Ph.D. in Neurobiology with in the next 4-5 years. His interests include sci-fi, PC-gaming, playing guitar, and a variety of other hobbies.
A Critical Thought: Bigfoot was last modified: July 2nd, 2015 by Riley Sproul