Allosaurus was a dinosaur that roamed the Earth about 154 to 144 million years ago, during the late Jurassic period.
It was known to be at the top of the food chain, preying on herbivorous dinosaurs and other animals. AnimalSake will throw light upon some interesting facts about Allosaurus.
Did You Know?
Allosaurus was the first dinosaur species to be depicted in a full-length movie―The Lost World―which was produced in 1925. I am sure he would have loved to see himself on the silver screen.
Allosaurus evolved during the late Jurassic period (about 150 million years ago), it is believed that they coexisted with large Theropods Ceratosaurus, and, Torvosaurus in present-day United States and Portugal.
The genus name, Allosaurus, is derived from the Greek word allos sauros, which means 'different lizard'. And the reason for this name was because of its unusual vertebrae as compared to other dinosaurs. It had 9 vertebrae in its neck, 5 supporting its hips, and 14 in the back.
Large-scale fossil findings have enabled paleontologists to establish that the Allosaurus were known to be the biggest meat-eaters in North America. They are members of the Theropoda group which include all carnivorous bipedal dinosaurs, including the popular T.rex.
Discovery
● The first ever remains of Allosaurus were discovered during the bone wars in 1869, in Middle Park, near Granby, Colorado by Ferdinand Vandeveer Hayden.
● Othniel Charles Marsh coined the name Allosaurus in 1877.
● In 1991, a Swiss team discovered Big Al, which was 95% complete, and in 1996, the same team discovered Big Al 2, known to be the best preserved skeleton.
Range and Habitat
● Paleontologists claim that Allosaurus lived in habitats with open plains, also they were fond of wetlands. Though difficult to prove, paleontologist also believe that Allosaurus were solitary hunters and much like tigers, covered vast tracts of land.
● They most likely lived in Europe and North America, as fossil remains have been discovered in the United States and Portugal.
● Paleontologists also discovered Allosaurus remains in Colorado, Montana, New Mexico, Oklahoma, South Dakota, Utah, and, Wyoming or what is called the Morrison Formation.
Size
● An average Allosaurus weighed no less than 4 tons, measured almost 40 feet (approximately 12 meters) in length, and were at least 17 feet (approximately 5 meters) tall.
● This means that they were as tall as 3 people standing head-to-toe over each other. We would look like babies in front of such giants.
● Allosaurus's skull was not that huge as compared to the other dinosaurs, it was modestly proportioned. The size of the skull was about 845 mm in length.
● The head had a pair of horns which were located right on top and in front of the eyes.
● It was a strong meat-eater with a strong S-shaped neck, walked on two powerful legs,built of massive tail, a heavy body, and, strong bones.
● Allosaurus had short arms with three-fingered hands, sharp claws which were 6 inches (15 cm) long, enough to rip an animal apart.
● It had large powerful jaws with long, sharp teeth 2 to 4 inches (5 to 10 cm) long. Each maxilla (main tooth bearing bones in the upper jaw) had between 14 and 17 teeth.
The teeth were more curved towards the back of the skull, bearing saw like edges, no wonder they were crazy about meat!! Their teeth used to shed easily, and were replaced on a continuous basis which made their teeth common fossil.
● The ribs were attached to the skin in the stomach area. Evidence of an Allosaurus attack was discovered on an Apatosaurus vertebra, with Allosaurus tooth marks on its body.
Diet
● It was believed to be an active predator of large animals, and the biggest meat-eater in its habitat. They had a well-developed sense of smell, which was very helpful to sniff their prey.
● Allosaurus is believed to have mostly hunted alone, and preyed on large dinosaurs like the long-necked Diplodocus and the Stegosaurus.
● Both the Tyrannosaurus rex and Allosaurus were carnivores and though Allosaurus lived in the late Jurassic period and T.rex during the upper Cretaceous period, more Allosaurus specimen have been found.
Lifespan
● Many factors are considered while estimating the lifespan of an animal, especially one which has been extinct for thousands of years now.
● The average lifespan of an Allosaurus was estimated to have been approximately 25 years, they reached adulthood at the age of 15.
Reproduction
● Paleontologist are not sure about the reproductive methods of Allosaurus, they had discovered many fossilized eggs of this species and have reached a conclusion that they laid eggs and young ones hatched from these. But the size and appearance of these eggs still remains a mystery.
Social Behavior
● Some paleontologist believe that Allosaurus had good relation with the members of their species, hunting in packs.
● While some believed they were aggressive towards each other, particularly when it came to sharing prey.
They were one of a kind dinosaurs. Their fossils are on display in many museums around the world for people to marvel at. Before we sign off, here's one more piece of interesting information, paleontologists have discovered Allosaurus droppings that are about 5 feet long and around 4 inches thick!
Now, that's what I would call a pile of dung. Newer finds and research are revealing stranger and interesting facts about these giants that once called Earth their home.