Allosaurus sp. Tooth-Colorado 004

 Taxa: Allosaurus sp.

Geology: Morrison formation

Age: Jurassic

Locality: Moffat County, Colorado

Tooth fragment. No repairs, restorations, or enhancements.

Morrison Formation

The Morrison Formation is a widespread sequence of sedimentary rocks from the Late Jurassic period (about 155–148 million years ago) found across the western United States, from Montana to New Mexico. It is composed mainly of mudstone, sandstone, siltstone, and limestone, and is famous for its rich dinosaur fossil beds. These rocks were deposited in river floodplains, lakes, and swamps, reflecting a variety of ancient environments. The Morrison Formation is the most productive source of Jurassic dinosaur fossils in North America.

Allosaurus sp.

Allosaurus was a large, bipedal, meat-eating dinosaur (theropod) that lived during the Late Jurassic period, around 152–145 million years ago, mainly in what is now North America. It averaged about 8.5–9.7 meters (28–32 feet) in length and weighed up to 2 tons. Allosaurus had a light but robust skull with sharp, serrated teeth, three-fingered hands with large claws, and distinctive bony ridges above its eyes. It was a top predator, likely hunting large herbivorous dinosaurs like Stegosaurus and Diplodocus, either alone or possibly in groups, though evidence for pack hunting is debated. Its name means "different lizard" or "different delicate reptile," referencing its unique vertebrae.