I have heard the following joke from a friend of mine: The zoo keeper was guiding a group of visitors through a zoo. He would stop by every cage and give the zoo guests a brief history of each caged animal. "Here", he said, "is a cross between a Swan and a Goose, which we call a Swoose. Over there is a Dope, which is a cross betwixt a Deer and an Antelope. Now here is a cross between a Fawn and a Duck. So far, we cannot think of a name for it.
(From the "Rest" of RHF)