Post by Barry the Baryonyx on Aug 26, 2007 14:08:46 GMT -5
Cryolophosaurus
copyright 2004-2007, Feenixx Publishing, Inc www.dinosaur-world.com/index.html
Cryolophosaurus (meaning "cold crest lizard") was a large bipedal dinosaur, with a bizarre crest on its head that looked like a Spanish comb. Due to the resemblance to Elvis Presley's pompadour haircut in the 1950s, the dinosaur was at one point informally known as the Elvisaurus.
Cryolophosaurus was discovered in Antarctica's Falla Formation by paleontologist Dr. William Hammer in 1991. It is the first carnivorous dinosaur to be discovered in Antarctica and the first dinosaur of any kind from the continent to be officially named. Dating from the Early Jurassic Period, it is also the earliest tetanuran theropod yet discovered.
Description
Cryolophosaurus was about 6 to 8 meters (20 to 26 feet) long, which is significantly smaller than the largest Allosaurus, which reached up to 12 meters (40 feet) in length.
A high, narrow skull was discovered, 65 centimeters (25 inches) long. The peculiar nasal crest runs just over the eyes, where it rises up, perpendicular to the skull and fans out. It is furrowed, giving it a comb-like appearance. It is an extension of the skull bones, near the tear ducts, fused on either side to horns which rise from the eye sockets (orbital horns). While other theropods like the Monolophosaurus have crests, they usually run along the skull instead of across it.
The crest is too fragile to be used in combat, so it was probably used in mating displays.
Forests of the night
The remains of the Cryolophosaurus were found in the Hanson Formation with the remains of a very large prosauropod (related to plateosaurids like the Plateosaurus and Lufengosaurus), a small pterosaur, a mammal-like reptile (a tritylodont, which is a type of synapsid about the size of a rat), and another unknown theropod. There were also fossilized tree trunks two meters away. The site is about 4,000 meters (13,000 feet) above sea level. During the early Jurassic it was a river bed on the southern coast of the supercontinent of Gondwana.
This supports the idea that, even at high altitudes, early Jurassic Antarctica had forests populated by a diverse range of species, at least along the coast. Even though Antarctica was closer to the equator and the world was considerably warmer than today, the climate was still cool temperate. Recent models of Jurassic air flow indicate that coastal areas probably never dropped much below freezing, although more extreme conditions existed inland. This suggests that dinosaurs could endure relatively cool environments and even possibly survive snow.
Cryolophosaurus was found about 650 kilometers (400 miles) from the South Pole but, at the time it lived, this was about 1000km or so farther north. Cryolophosaurus, therefore, did not have to contend with the polar night.
The specimen was found in conjunction with a platter from the prosauropod which has led to speculation that it may have choked to death, although there is no concrete evidence of this one way or the other.
Copyright © 2007 Answers Corporation