Absence of Evidence
Science requires conclusive evidence to separate fact from legend which in this case might be biological evidence, fossilized remains, or even a living specimen. With Bigfoot, eyewitness testimony only provides an interesting viewpoint for a case and not enough for verdict. As Carl Sagan once said, we must concede that: If you never looked for evidence, or if you wouldn't have found it even if you looked, then the absence of evidence isn't evidence of anything. Perhaps the fossil record does not indicate the presence of Homo erectus in the last 300,000 years simply because we haven't found the right places to look. There are a multitude of factors of why archeology continues to find gaps in biological time-lines especially considering the ever-changing dynamic of our world. The fact is: All over the world people are reporting sightings of large human-like creatures dwelling in the backwoods of civilization.
More recently have these sightings been taken to the next level with trained professional field biologists discovering unknown DNA evidence, highly suggesting the existence of a previously undiscovered species. To many scientists the idea of Bigfoot is far-fetched but not completely ruled out, usually met with a skeptic approach saying if they did exist, we would know about it by now. In all honesty, such a statement is closed-minded, lacks imagination, and is very repressive to aspiring scientists.
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