“I can see the optic nerve that gave vision,” he says, as if the skull’s former occupant still lives. “I can see the abducens nerve, which allowed lateral eye motion, and the trigeminal nerve, which gave sensation to the skin of the face.”

The surgeon has asked not to be identified in this article. Owning a collection of fossil skulls makes him both gleefully happy and nervously discreet, like many collectors in town for the Tucson Gem and Mineral Show. He’s building a “private museum” to house the skulls, and he grins at the thought of displaying them in chronological order: the 36-inch-long Allosaurus skull, the toothy sea monster Elasmosaurus, and the most complete skull of a Pteranodon ever found.

Private fossil