He is, though, not dumber than rocks, and was thus not the target of my comment.
Interesting story: My former office mate and I were talking with some guys down the hall and he asked if there was anything interesting to do in NE Iowa. I suggested they go "caving" at spook cave and the ice caves up around Decorah.
I've lived here most of my life, so it never occurred to me that an ice cave was an oddity, but for the life of them, they couldn't figure out how it could be iced year-round. My office mate called his wife (PhD in geology), who promptly told us, "The Earth has cold spots in it, it just happens."
Probably just a relict environment surviving from the last glacial event -- that would be the Younger Dryas, which is just younger than what we laughingly call the "Holocene" boundary. (News flash: Earth to People, We're still in the Pleistocene -- get ready for the resumption of continental glaciation in approximately 800-1500 years. Unless we can string things out a bit by burning all the soft coal in China).
Other relict environments are usually floral -- one in the Guadalupe Mountains of Texas, which retain elements of their old floral assemblage, which resembles the average mountainside in southern Colorado. I've been told about a valley in the Alabama Hills that has a northern Appalachian ecology (what, no kudzu?), complete with assorted maples and birch.
Like the PhD said, "it happens".
So much for Iowans.