Thanks to unexplained drowning deaths in Oklahoma lakes over the past few years, a strange theory has begun spreading its tentacles. According to some, what's to blame is... a killer freshwater octopus. It's true the octopus is an adaptive wonder, capable of living just about anywhere in the world's oceans, but Scientific American pokes a couple of holes in the "Oklahoma Octopus" theory. For one, adapting to freshwater would be a major feat, even for an octopus, since it would take some extreme changes on a cellular level.
Not only would an octopus have had to adapt to freshwater, but it would have needed to make "its way up the Mississippi and subsequent smaller rivers, swimming upstream—and navigating numerous dams," SA explains, since the majority of Oklahoma lakes were man-made by damming rivers. And then there's the fact that, unlike, say, Bigfoot, there isn't even "improbable" photo evidence of the creature. And so, the "Oklahoma Octopus" lives on as legend and the drowning deaths remain unexplained—"except by a few folks who proffer that giant catfish are to blame," SA quips. (Read more octopus stories.)