Diplodocus

Dinosaurs > Diplodocus

Diplodocus is an extinct genus of diplodocid sauropod dinosaur whose fossils were first discovered in 1877 by S. W. Williston. The generic name, coined by Othniel Charles Marsh in 1878, means “double beam”, in reference to its double-beamed chevron bones located in the underside of the tail. These bones were initially believed to be unique to Diplodocus; however, they have since then been discovered in other members of the diplodocid family and in non-diplodocid sauropods such as Mamenchisaurus.

This genus of dinosaurs lived in what is now western North America at the end of the Jurassic Period. Diplodocus is one of the more common dinosaur fossils found in the Upper Morrison Formation, a sequence of shallow marine and alluvial sediments deposited about 155 to 148 million years ago, in what is now termed the Kimmeridgian and Tithonian stages (Diplodocus itself ranged from about 154 to 150 million years ago). The Morrison Formation records an environment and time dominated by gigantic sauropod dinosaurs such as Camarasaurus, Barosaurus, Apatosaurus and Brachiosaurus.

Diplodocus is among the most easily identifiable dinosaurs, with its classic dinosaur shape, long neck and tail, and four sturdy legs. For many years, it was the longest dinosaur known. Its great size may have been a deterrent to the predators Allosaurus and Ceratosaurus: their remains have been found in the same strata, which suggests they coexisted with Diplodocus.

One of the best-known sauropods, Diplodocus was a very large long-necked quadrupedal animal, with a long, whip-like tail. Its forelimbs were slightly shorter than its hind limbs, resulting in a largely horizontal posture. The long-necked, long-tailed animal with four sturdy legs has been mechanically compared with a suspension bridge. In fact, Diplodocus is the longest dinosaur known from a complete skeleton.

Diplodocus

Clade: Dinosauria
Suborder: Sauropoda
Family: Diplodocidae

Size: 33m (108 feet) long

Weight: 12 metric tons

When: Jurassic Period
154 to 150 million years ago

Where: North America

Diet: Herbivore

The skull of Diplodocus was very small, compared with the size of the animal, which could reach up to 35 m (115 ft), of which over 6 m (20 ft) was neck. Diplodocus had small, ‘peg’-like teeth that pointed forward and were only present in the anterior sections of the jaws. Its braincase was small. The neck was composed of at least fifteen vertebrae and may have been held parallel to the ground and unable to be elevated much past horizontal.

Recent discoveries have suggested that Diplodocus and other diplodocids may have had narrow, pointed keratinous spines lining their back, much like those on an iguana. This radically different look has been incorporated into recent reconstructions, notably Walking with Dinosaurs. It is unknown exactly how many diplodocids had this trait, and whether it was present in other sauropods.

Diplodocus has highly unusual teeth compared to other sauropods. The crowns are long and slender, elliptical in cross-section, while the apex forms a blunt triangular point. The most prominent wear facet is on the apex, though unlike all other wear patterns observed within sauropods, Diplodocus wear patterns are on the labial (cheek) side of both the upper and lower teeth. What this means is Diplodocus and other diplodocids had a radically different feeding mechanism than other sauropods. Unilateral branch stripping is the most likely feeding behavior of Diplodocus, as it explains the unusual wear patterns of the teeth (coming from tooth–food contact). In unilateral branch stripping, one tooth row would have been used to strip foliage from the stem, while the other would act as a guide and stabilizer. With the elongated preorbital (in front of the eyes) region of the skull, longer portions of stems could be stripped in a single action.


Source: Wikipedia