Nanotyrannus lancensis fossil confirms distinct species, challenging T. rex research

A fossil of a Nanotyrannus lancensis, found in the "Dueling Dinosaurs" specimen, has been confirmed as a distinct, mature species, ending a long debate. Researchers used growth ring analysis and skeletal features to prove the tyrannosaur was a 20-year-old adult, not a juvenile T. rex, overturning decades of prior research. This finding suggests greater predator diversity in the late Cretaceous period and implies other small dinosaur species may have been misidentified.