Researchers have controversially argued there is enough variation in samples to point towards three species of Tyrannosaur, not one.
T. rex grew beefier than museum fossils suggest
How did T. rex get such keen, predatory senses? New tyrannosaur offers hints.
New dinosaur was more dangerous than Tyrannosaurus Rex - Deseret News
13 Things Paleontologists Got Wrong About Tyrannosaurus Rex
Splitting T. Rex Into 3 Species Becomes a Dinosaur Royal Rumble - The New York Times
Tyrannosaurus Skeletal Remains Reveal T. rex May Have Been 3 Distinct Species
Tyrannosaurus rex may have been three separate species, say scientists, rex
Was there more than one species of Tyrannosaurus? Charleston professor thinks there may have been.
Newly discovered, primitive cousins of T. rex shed light on the end of the age of dinosaurs in Africa
Mistaken identity? Scientists say this dinosaur isn't T-rex