After the "serpent" of Eden smooth-talked humanity's mother, resulting in a whole chain of events leading up to Pat Robertson and popes explaining the story thousands of years later, he was supposedly punished:
Because thou hast done this, thou art cursed above all cattle, and above every beast of the field; upon thy belly shalt thou go, and dust shalt thou eat all the days of thy life...
My observation is this: if the serpent was made to crawl on its belly after this event, what kind of "serpent" was it pre-punishment? A snake with legs? If so, that would be pretty close to a lizard, right? Why didn't the bible writers notice this distinction and call it a lizard (or equivalent) and note its transformation to a new life form post-punishment? Bad editing? Lack of reason? Foreshadowing of the anti-evolution position that would be taken up by Kirk Cameron?
Also, if it was the talking that was the sin, why didn't the serpent's ability to talk get taken away instead, eliminating the ability to do it again? We don't have talking snakes/lizards (while sober, anyway), so using this story to explain their silence would have made more sense, I think. Maybe various animals still spoke to humans for a while afterwards but no one bothered to write down a conversation or two after "the incident."
Now, this is in all likelihood not an original thought. I just haven't really seen it anywhere.