A small dinosaur skull found in Montana 40 years ago was thought to be a young T. rex. Turns out it was a smaller, faster ...

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

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

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

For many years, paleontologists have debated about whether there was a smaller relative of the Tyrannosaurus rex, or if those ...

What if everything we know about T. rex growth is wrong? A complete tyrannosaur skeleton has just ended one of paleontology's ...

Now, a research team says new evidence resolves the case. The latest clue comes from a complete skeleton — first uncovered in Montana in 2006 — that scientists say identifies the mystery reptile as ...

The fossil skull of a mystery tyrannosaur has been the subject of debate since it was discovered in the 1940s.

A fossil of two dinosaurs locked in battle shows the smaller of the pair wasn’t a young T. rex but a full-grown predator of ...

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

A new tyrannosaur species has just been found in Canada, and paleontologists say that it is the oldest Tyrannosaurus rex ever found in the country. Thanatotheristes degrootorium, who lived nearly 80 ...

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