Alternative Heads

Display at the University of Michigan

The Diplocaulus magnicornis on display at the Natural History Museum at the University of Michigan is a special duck, as my mother sometimes says. The fossil is as about as normal as any other Diplocaulus fossil that has ever been found. The head and vertebral column were well preserved while the shoulder girdle, pelvic girdle, ribs, and all limb elements have been lost in this specimen. The most interesting thing about the specimen is actually the hypothetical reconstruction that accompanies it within its display. The flattened head, in this hypothetical recreation, supports a petagium that extends back over the body, attaching to the caudal portion of the pelvic girdle. This petagium makes the robust little salamander look much more like a squid than an amphibian. If this morphology was even a partial reality, a muscular portion of the attachment might have made Diplocaulus almost part skate or ray in the way in which it swam. A salamander-like animal undulating through the water would be interesting, but it probably was not very likely.