An argument over whether fossils from several small dinosaurs represent a juvenile Tyrannosaurus rex or smaller adults of a ...

After decades of fierce debate, researchers say fossils once thought to be juvenile T. rex actually belong to a separate, ...

Specifically, whether or not certain fossils found in Montana belonged to a young Tyrannosaurus rex or a completely separate, ...

Paleontologists have long debated whether small tyrannosaurs were their own species or simply teenage T. rexes. This debate ...

For more than three decades, paleontologists have argued over whether a lithe predatory dinosaur called Nanotyrannus ever ...

For decades, paleontologists debated whether fossils were of a young T. rex or a species called nanotyrannus. A new study ...

By Will Dunham WASHINGTON (Reuters) -At the twilight of the age of dinosaurs, an agile and vicious predator named Nanotyrannus prowled western North America, resembling a smaller version of ...

A long-standing dinosaur mystery has finally been solved, revealing surprising details about a small predator that once lived in the shadow of the mighty Tyrannosaurus rex.

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

The new species is called Nanotyrannus. Compared to the well known tyrannosaurus rex, a nanotyrannus was more speedy and ...

A new specimen of one of the most controversial species of dinosaur has the potential to overturn decades of research on the ...