Not being familiar with the term, the doctor asked him what a fencepost turtle was.

The old farmer said, "when you're driving along a country road and you come across a fence post with a turtle balanced on top, that's called a fencepost turtle."

The old farmer saw a puzzled look on the doctor's face, so he continued to explain, "You know he didn't get up there by himself, he definitely doesn't belong up there, he doesn't know what to do while he is up there, and you just gotta wonder what kind of dill put him up there in the first place!''