ALLOSAURUS
"Different Lizard"
Allosaurus was a powerful predator that walked on two powerful legs, had a strong, S-shaped neck, and had vertebrae that were different from those of other dinosaurs (hence its name, the "different lizard"). It had a massive tail, a bulky body, and heavy bones. Its arms were short and had three-fingered hands with sharp claws that were up to 6 inches (15 cm) long. Allosaurus was up to 38 feet long (12 m) and 16.5 feet tall (5 m). It weighed about 1400 kg. It had a 3 feet long (90 cm) skull with two short brow-horns and bony knobs and ridges above its eyes and on the top of the head. It had large, powerful jaws with long, sharp, serrated teeth 2 to 4 inches (5 to 10 cm) long.
Allosaurus may have hunted in groups. In groups, Allosaurus could ambush even the very large sauropods (like Diplodocus and Camarasaurus). It probably also preyed upon stegosaurs and iguanodonts. Allosaurus was the most abundant predator in late Jurassic North America. Allosaurus may have faced competition from the meat-eating Ceratosaurus.
Allosaurus was a carnosaur, whose intelligence (as measured by its relative brain to body weight, or EQ) was high among the dinosaurs.
Allosaurus walked on two muscular legs. Allosaurus' leg length was about 1.38 m; its stride length (distance between footprints) was about 2.72 m. Allosaurus' femur (thigh bone) was about 30 inches (77 cm) long.
There has been some discussion on whether or not the massive, short-armed theropods (like T. rex, Giganotosaurus, Albertosaurus, and Allosaurus) could run very fast because if they fell, their short arms would not break their fall and they would be badly injured (James Farlow, 1995). This meant that these large theropods were slow, lumbering animals.
Dr. Bruce Rothschild, of the Arthritis Center of Northeast Ohio, has found evidence of 14 fractured ribs in an Allosaurus that reflect healed injuries that were probably received in falls. These were most likely bellyflops that happened while running (as reported in the April 16, 1998, New Scientist).
An X-ray analysis of the Allosaurus fossil indicated that the Allosaurus ribs near the scapula (the shoulder bone) were cracked and had healed. The Allosaurus was capable of recovering after many severe forward tumbles that probably occurred while it was running. So the suggestion that perhaps the large short-armed theropods were not capable of running because they couldn't recover after a fall apparently wasn't so, at least for Allosaurus - this Allosaurus did recover many times after bad tumbles.
In 1995 James Farlow of Indiana's Purdue University argued that a large T. rex could run no faster than 20 mph (32 kph), because if it did, a fall would probably be so severe as to kill it. T. rex weighed about 6 tons and was up to 20 feet (6 m) tall but Allosaurus was slightly smaller, about 3 tons and 16.5 feet (5 m) long. Farlow says that Rothschild's analysis is consistent with his theory since Allosaurus was smaller and lighter than T. rex (its smaller mass would make the impact much less powerful so the animal may have been able to recover after a running fall).
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In Mayfield Village, the Greenway Corridor will provide a safe walking and biking route from Center School on Wilson Mills Road to Parkview Pool, playgrounds, baseball and soccer fields, the Cuyahoga County Library’s new Mayfield Branch, and ultimately the North Chagrin Reservation of the Metroparks. More info: https://www.mayfieldvillage.com/recreation/greenway-trail.