Everything scientists believed about the T-Rex could be wrong after a study proved the existence of its smaller cousin.

For many years, paleontologists have debated about whether there was a smaller relative of the Tyrannosaurus rex, or if those smaller fossils were really just awkward teenage versions of the king of ...

At the twilight of the age of dinosaurs, an agile and vicious predator named Nanotyrannus prowled western North America, ...

Researchers say they have uncovered a case of mistaken identity and found evidence of a species called Nanotyrannus lancensis.

A new look at the "Dueling Dinosaurs" fossil reveals that Tyrannosaurus rex was not the only tyrannosaur roaming the land.

Scientists have long puzzled over the origins of a mysterious dinosaur excavated in the 1940s: Was it a young T. rex or ...

Paleontologists have long debated whether Tyrannosaurus rex was a predator or a scavenger. In most previous analyses, scientists have scrutinized the creature’s teeth and jaws. Now, Graeme D. Ruxton ...