I couldn't help it. When I read this passage from The New Book of Lists, I immediately thought of the vertical foreplay in American discos circa 1978:
Hippos have their own form of aromatherapy. They attract mates by marking territory, urinating and defecating at the same time. Then, an enamored hippo will twirl its tail like a propeller to spread this slop in every direction. This attracts lovers . . ."
