Ceratosaurus facts for kids
Quick facts for kids CeratosaurusTemporal range: Upper Jurassic
|
|
|---|---|
 |
|
| Scientific classification | |
| Kingdom: | |
| Phylum: | |
| Class: | |
| Superorder: | |
| Order: | |
| Suborder: | |
| Infraorder: | |
| Family: |
†Ceratosauridae
|
| Genus: |
†Ceratosaurus
|
Ceratosaurus was a predatory dinosaur from the Upper Jurassic period, 156 to 145 million years ago. It had a large horn on its nose, and a pair of smaller horns in front of its eyes. Uniquely among theropods, Ceratosaurus had armor, in the form of small osteoderms running down the middle of its back.
Contents
Paleobiology
Feeding
Ceratosaurus lived alongside dinosaurs such as Allosaurus, Torvosaurus, Apatosaurus, Diplodocus, Stegosaurus and Camarasaurus. Ceratosaurus reached lengths of 6.7 m (22 ft), and weighed up to 980 kilograms (2,160 lb). It was smaller than the other large carnivores of its time (allosaurs and Torvosaurus) and likely occupied a distinctly separate niche from them. Ceratosaurus fossils are noticeably less common than those of Allosaurus, but whether this implies Ceratosaurus being rarer is uncertain (animals with certain lifestyles are more biased toward fossilization than others). Ceratosaurus had a longer, more flexible body, with a deep tail shaped like that of a crocodilian. This suggests that it was a better swimmer than the stiffer Allosaurus. A recent study by Robert Bakker suggested that Ceratosaurus generally hunted aquatic prey, such as fish and crocodiles, although it had potential for feeding on large dinosaurs. The study also suggests that sometimes adults and juveniles ate together. This evidence is debatable, and Ceratosaurus tooth marks are very common on large, terrestrial dinosaur prey fossils. Scavenging from corpses, smaller predators, and after larger ones also likely accounted for some of its diet.
Ceratosaurus, Allosaurus and Torvosaurus appear to have had different ecological niches, based on anatomy and the location of fossils. Ceratosaurus and Torvosaurus may have preferred to be active around waterways, and had lower, thinner bodies that would have given them an advantage in forest and underbrush terrains, whereas Allosaurus were more compact, with longer legs, faster but less maneuverable, and seem to have preferred dry floodplains. Ceratosaurus, better known than Torvosaurus, differed noticeably from Allosaurus in functional anatomy by having a taller, narrower skull with large, broad teeth. Allosaurus was itself a potential food item to other carnivores, as illustrated by an Allosaurus pubic foot marked by the teeth of another theropod, probably Ceratosaurus or Torvosaurus. The location of the bone in the body (along the bottom margin of the torso and partially shielded by the legs), and the fact that it was among the most massive in the skeleton, indicates that the Allosaurus was being scavenged.
Nasal horn
_-_AMNH_-_DSC06292.JPG)
Marsh (1884) considered the nasal horn of Ceratosaurus to be a "most powerful weapon" for both offensive and defensive purposes, and Gilmore (1920) concurred with this analysis. However, this interpretation is now generally considered unlikely. Norman (1985) believed that the horn was "probably not for protection against other predators," but might instead have been used for intraspecific combat among male ceratosaurs contending for breeding rights. Paul (1988) suggested a similar function, and illustrated two Ceratosaurus engaged in a non-lethal butting contest. Rowe and Gauthier (1990) went further, suggesting that the nasal horn of Ceratosaurus was "probably used for display purposes alone" and played no role in physical confrontations. If used for display, it is likely that the horn would have been brightly colored.
Images for kids
-
C. nasicornis skeleton restoration by Othniel Charles Marsh from 1896, depicted in an erroneous upright position and with excess vertebrae in the spine resulting in an overly elongated trunk
-
Reconstruction of the holotype specimen of C. nasicornis by Charles W. Gilmore, 1920, showing known elements
-
Probably the first life restoration of Ceratosaurus, drawn in 1899 by Frank Bond under the guidance of Charles R. Knight, but not published until 1920
-
Restoration of C. nasicornis by Joseph M. Gleeson from 1901, made under supervision of Charles R. Knight.
-
Diagram of the Ceratosaurus nasicornis holotype skull in top and side view by Charles Gilmore, 1920: This reconstruction is now thought to be too wide in top view.
-
Artist's impression of C. nasicornis
-
Distinguishing skull features of Ceratosaurus: The fused left and right nasal bones form a prominent nasal horn (top), and the teeth of the upper jaw are exceptionally long (bottom). These fossils are part of specimen MWC 1 from Fruita, Colorado, and are on display at the local Dinosaur Journey Museum.
-
C. nasicornis holotype, as mounted by Charles Gilmore in 1910 and 1911, National Museum of Natural History
-
Mounted cast of a juvenile skeleton, Dinosaur Discovery Museum
-
Dry season at the Mygatt-Moore Quarry showing Ceratosaurus (center) and Allosaurus fighting over the desiccated carcass of another theropod
-
Reconstructed skeletons of Allosaurus and C. nasicornis in fighting postures, at Dinoworld Expo, Yokohama
-
Restoration of a feeding C. nasicornis
-
Juvenile skull in multiple views
-
Ceratosaurus in its environment.
.jpg)
See also
In Spanish: Ceratosaurus para niños
