According to scientists, Dunkleosteus terrelli was a giant prehistoric fish belonging to the placoderms. It had the most powerful jaws of any fish. Be it a shark or huge crustacean, this marine beast gutted anything that came its way. Taking its powerful jaws into consideration, Dunkleosteus was believed to be the dominant predator of the Devonian period. Scientists though, are unsure about its level in the food chain. Nevertheless, species like Dunkleosteus terrelli make living fossils the subject of common interest among scientists and eccentric explorers.