Allosaurus has a big skull with a big hole in it, which can reduce weight. There is a horn crown above the eyes. Their skulls are composed of several independent bones with movable joints between them. When eating, their jaws can open up and down first, then open left and right to swallow food. Their jaws can also slide back and forth. There are dozens of big, sharp and curved teeth in the lower jaw. [1] Compared with the big and strong hind limbs, their forelimbs are smaller, with three fingers in their hands and big and curved fingers, which are 25 cm long. A long and heavy tail can balance the body and head. The bones of Allosaurus, like other theropods, are light and hollow like birds.
Allosaurus was the most common large predator of Morrison Formation in North America during this period, and it was at the top of the food chain. They may have eaten other large herbivorous dinosaurs, such as ornithopoda, stegosaurus and sauropoda. Allosaurus is usually considered to attack sauropods in a cooperative way, but there is little evidence that Allosaurus has a social behavior of * * * attacking together. They may attack large prey by ambush and hit them with their jaws.
The first fossil that can be clearly classified as Allosaurus was discovered by othniel charles marsh in 1877. Allosaurus has a complicated taxonomic history. Many species were originally classified as Allosaurus, but now they are classified as individual genera. The most famous species is the model species Allosaurus fragilis (Allosaurus fragilis). Allosaurus was called a body cavity motor for a long time in the 20th century. It was not until a large number of fossils were found in Lloyd's quarry in Cleveland that Allosaurus became a common name and became one of the most widely studied dinosaurs.
The fossils of Allosaurus mainly come from Morrison Formation in North America, and possible fossils have also been found in Portugal and Tanzania. Allosaurus fossil is a state fossil in Utah, USA. Because Allosaurus is one of the earliest discovered theropods, it has attracted the attention of the general public for a long time and appeared in many movies and TV programs.