Favorite Oldies

One of my favorite theropod dinosaurs is the medium sized so-called "horned lizard" Ceratosaurus. A genus consisting of three recognized species (C. nasicornis Marsh, 1884 (type), C. dentisulcatus Madsen and Welles, 2000, C. magnicornis Madsen and Welles, 2000) and one junior synonym that has been applied to the type species, Ceratosaurus was a Jurassic carnivore sharing the landscape with large sauropods, stegosaurs, and allosaurs. Known from North America, Europe and Africa, Ceratosaurus was a widely distributed and successful predator eclipsed during its existence only by the larger and equally successful Allosaurus. Though we consider Ceratosaurus to be a medium sized predator in the context of all theropods, at 5.69 m (18.7 ft) long; C. nasicornis is fairly large; the largest species C. dentisulcatus is estimated at 7 m (23 ft) long. The feature responsible for the name of this dinosaur is a large rugosity on the dorsal surface of the muzzle that appears to some to look like a horn; the type material was more horn-like than some of the later discoveries, but for the most part these rugosities are variable and can look like anything from horns to small ridges. Because we have so many remains of these animals, their ecosystems, and their contemporaries we know a lot about their life history, ecology, and the world that was around them. We also know enough about their feeding ecology that we can build awesome museum displays like this one at theNatural History Museum of Utah.