Velociraptor

In 1923, the crushed skull and sickle-shaped second toe of a small, turkey-sized dinosaur was found in the Late Cretaceous sandstones of the Djadokhta Formation in the Gobi Desert of Mongolia. Henry Fairfield Osborn, president of the American Museum of Natural History and leader of the expedition, designated the skull and claw as the type specimen of a new genus, Velociraptor, from the Greek velox (‘swift’ or ‘speedy’) and raptor (‘robber’ or ‘plunderer’). With over a dozen recovered skeletons, Velociraptor remains well-known to paleontologists and the public alike.

Physical Characteristics

Velociraptor is a genus of dromaeosaurid theropod dinosaurs that existed during the Late Cretaceous around 85 to 70 million years ago. It consists of two recognized species, V. mongoliensis and V. osmolskae. At a length of around 6 ft or 2 meters and weighing up to 33 lbs or 15 kg, Velociraptor was smaller than its dromaeosaurid cousins Deinonychus and Achillobator. Despite its length, Velociraptor probably only stood about as tall as a large dog.

Velociraptors were bipedal, and carried an enlarged sickle-shaped claw on their second toe. Like the birds of today, Velociraptors also had hollow bones which made them quite light. Most of their length comes from a long tail that was held erect by ossified (bone-like) tendons. They are also easily recognized by their low, tapered head which is usually around 9.8 in or 25 cm in length. Velociraptor’s snout was elongated and turned upward slightly, a feature not shared with other dromaeosaurids. Designed to slice through flesh, its jaws were full of serrated teeth.

Other dromaeosaurids have long been known to have had fully-feathered bodies and fully-developed feathered wings. Until 2007, however, no evidence could support the theory that Velociraptor also had feathers. In September 2007, researchers found quill knobs on the forearm of a Velociraptor found in Mongolia. Quill knobs are the bumps on the bone where feathers anchor to the bone and are a sure indicator that Velociraptor indeed had feathers. To a modern human, Velociraptor probably would have looked like a strange bird. Although it sported strong arms and chest muscles, its forelimbs were too short to provide enough lift for flight.

Diet and Behavior

According to a 2010 article by Hone and colleagues, Velociraptor was probably both a hunter and a scavenger. Its long, stiff tail would have stabilized the dinosaur at high speeds, and its warm-blooded nature would have provided the energy required for such speed. Fossil evidence indicates that while its relative Deinonychus might have hunted in packs, Velociraptor did not. When hunting, the dinosaur could use its wicked sickle claw to slash the vital organs of the throat, such as the carotid artery, jugular vein, and trachea. The claw, while impressive and lethal, probably was insufficient to disembowel prey. When scavenging, the raptor’s deft jaws would enable the animal to rip out parts of the carcass left behind by larger carnivores.

The famous “Fighting Dinosaurs” fossil, which preserves a single Velociraptor locked in combat with a Protoceratops, indicates that Velociraptor most likely preyed upon Protoceratops and other herbivores, as well as smaller animals such as lizards.

Popular Culture

In Steven Spielburg’s “Jurassic Park,” the Velociraptors were in fact modeled after their larger relative, Deinonychus, for dramatic effect. The human characters excavate a “Velociraptor” skeleton in Montana, far from the range of the Asian range of the true Velociraptor and well within the range of Deinonychus. Another obvious difference is that the movie Velociraptors had few, if any, feathers, unlike the full plumage a Velociraptor would have had.

Source:

Dinosaurs: A Textbook