Add Yahoo as a preferred source to see more of our stories on Google. A handout illustration shows a pack of the dinosaur Nanotyrannus attacking a juvenile Tyrannosaurus in what is now Montana 67 ...

For decades, a small tyrannosaur skull has divided paleontologists over whether it belonged to a separate species or a teenage Tyrannosaurus rex. New research anchored in the spectacular “Dueling ...

What if everything we know about T. rex growth is wrong? A complete tyrannosaur skeleton has just ended one of paleontology's longest-running debates—whether Nanotyrannus is a distinct species, or ...

For decades, paleontologists argued over the lone skull used to establish the distinct species Nanotyrannus. Was it truly a separate species or simply a juvenile Tyrannosaurus rex? A new paper ...

At the twilight of the age of dinosaurs, an agile and vicious predator named Nanotyrannus prowled western North America, resembling a smaller version of Tyrannosaurus – about a tenth the body mass – ...

Add Yahoo as a preferred source to see more of our stories on Google. The skeleton of a Nanotyrannus lancensis is displayed as part of the "Montana Dueling Dinosaurs & Distinguished Fossils" ...