A photograph of the Dunkleosteus terrelli fossil skull. This ancient fish had a bite that exerted 11,000 pounds of force, the strongest bite of any fish ever, and one of the strongest bites of any animal. The bladed dentition focused the bite force into a small area, the fang tip, at an incredible force of 80,000 pounds per square inch. Credit: Photograph by Michael LaBarbera, courtesy of The Field Museum