Growth rings in fossilized bones suggest the diminutive dinosaur, Nanotyrannus, would never grow up to become a T. rex — plus ...

For years, paleontologists have debated whether the T. rex-like dinosaur in the fossilized tableau and others are indeed ...

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

Nanotyrannus lethaeus was a fast, agile predator distinct from T. rex, with longer legs, stronger arms and a body built for ...

Debate kicked off in 1988 when a single small tyrannosaur skull discovered four decades earlier was given its own species ...

A new analysis of a controversial tyrannosaur fossil reveals the dinosaur wasn't a teenage version of T. rex as once thought, but instead a distinct miniature dinosaur.