Paleontologists have discovered Allosaurus fragilis’ older cousin Allosaurus jimmadseni in Utah, believed to have existed around 157 million years ago during the late Jurassic period. By Tanvi Jain
In a recent discovery in the world of science, paleontologists have found Allosaurus jimmadseni in Utah, a meat-eating dinosaur, oldest of its kind, believed to have existed some 157-152 million years ago. The fossils of this newly discovered dinosaur species was unveiled at the Natural History Museum of Utah.
These carnivorous dinosaurs belonging to the group called Allosauroids, are believed to have inhabited the semi-arid Morrison Formation floodplains of the interior of western North America, during the Jurassic and Cretaceous periods. Allosaurus jimmadseni is even older than Allosaurus fragilis, which was once made the state’s official fossil. The two can be distinguished by their skull, as the former had a lightly built skull, thereby possessing a different feeding behaviour as well.
Based on the remains, the researchers have figured out the dinosaur’s height to be around 26 to 29 feet and weight to be around 4,000 pounds. The initial skeleton was discovered by George Engelmann of the University of Nebraska, Omaha, within Dinosaur National Monument. Later in 1996, the radioactive skull of the headless skeleton was discovered by Ramal Jones of the University of Utah, with the help of a radiation detector.
This time it was the radioactive skull that was located at first, which is not uncommon as surrounding sediments result in radioactive elements leaching in the bones with time. After recognising the skull, the team of Dinosaur National Monument, managed to identify the remaining body of the newfound species as well.
Utah is the hub of fossilised dinosaur remains. The Dinosaur National Monument grabbed attention back in 1909, when Earl Douglass, a Paleontologist Carnegie Museum of Pittsburgh found eight dinosaur tailbones protruding from a sandstone hill. Later in 1915, the site was declared as a national monument.
Today, tourists visit the monument’s Quarry Exhibit Hall to gaze at a rock wall of approximately 1,500 fossilised dinosaur bones, or to take a rafting trip down the Yampa or Green rivers that course through the monument.