Eras of Life
 Dinosaur Evolution
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  Bonitasaura salgadoi
  Carnotaurus sastrei
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  Ceratosaurus nasicornisi
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  Dilophosaurus wertherelli
  Euoplocephalus tutus
  Giraffatitan brancai
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  Masiakasaurus knofleri
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  Parasaurolophus walkeri
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 Prehistoric Sea Monsters

Dilophosaurus wertherelli (Samuel P. Wells, 1954, 1984)

Dilophosaurus wertherelli dinosaur
Name Means: "Double Crested Lizard" Length: Length:22 feet (7 m)
Pronounced: die-Loaf-o-Saw-rus Weight: Weight:1,000 pounds (450 kilos)
When it lived: Early Jurassic - 190 MYA    
Where found: Arizona, USA.    
Dilophosaurus was the largest meat-eater of the early Jurassic. It was made famous by the movie Jurassic Park, but the movie did not present an accurate picture of this dinosaur. The movie version (1) sported a retractable frill around its neck, much like the famous Australian frilled lizard (2) was much smaller than the real thing, had forward facing eyes to give it stereo vision and (4) spat poison, aimed at eyes of its prey, to blind and paralyze it. None of these characterized the real Dilophosaurus
    But he was a very powerful animal that stood about eight feet high.  He weighed as much as a small horse had had long, strong hind legs; forelimbs with hand that were flexible, with an opposable thumb, so he could grasp a prey.  His hind legs, his feet, were armed with very powerful claws and were probably used as weapons as well as for locomotion. He bipedal and probably a very rapid runner.  He had long and slender, rear-curving teeth in long jaws. Dilophosaurus was carnivore, but had loosely attached jaws which would have made killing animals with its teeth difficult. It must have killed with its clawed arms and legs then used his teeth to pluck meat from the carcass.  In any event, he was the most capable killing machine of his time so he certainly didn't to use poison.
   The first fossil Dilophosaurus skeletons came from the Navajo Indian Reservation, just west of Tuba City, Arizona. were found in Arizona, USA, in the 1940's.  A local Navajo guided Bill Rush, Ed Kott and Samuel P. Welles of the University of California at Berkeley to them. Wells said,  "There were three dinosaurs in a triangle about twenty feet apart and one was almost worthless having been completely eroded. The second was a good skeleton showing everything except the front part of the skull."  "The third gave us the front part of the skull and much of the front part of the skeleton. These we collected in a ten day rush job, loaded them into the car, and brought them back to Berkeley."  Since three specimens were found together, Dilophosaurus may have roved in packs.
   The fossils of Dilophosaurus were found near large footprints of carnivorous dinosaurs and they may belong to Dilophosaurus
   The original description was published in 1954 by Welles.  At that time, it was thought to be another genus of theropod (Megalosaurus). In 1970, it was recognized to be distinct and given its own generic name Dilophosaurus (meaning "two-crested lizard"). Welles later redescribed the entire taxon in 1984 in a much more complete paper. Dilophosaurus may be a primitive member of the clade containing both ceratosaurian and tetanuran theropods. Alternatively, some paleontologists classify this genus as a large coelophysoid.
    There is another species of Dilophosaurus (D. sinensis) which may or may not belong to this genus. It is possibly closer to the bizarre Antarctic theropod Cryolophosaurus, based on fact that the anterior end of the jugal does not participate in the internal antorbital fenestra and that the maxillary tooth row is completely in front of the orbit and ends anterior to the vertical strut of the lacrimal. This species was recovered from the Yunnan Province of China in 1987 with the prosauropod Yunnanosaurus, and later described and named in 1993 by Shaojin Hu.


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