rex

Could everything we thought we knew about T. rex growth be wrong?

A remarkably complete tyrannosaur skeleton has brought new clarity to one of paleontology's longest debates: whether Nanotyrannus was its own species or merely a young Tyrannosaurus rex.

After extensive analysis, scientists have confirmed that the smaller predator was not a juvenile T. rex, but an adult Nanotyrannus lancensis.

"This fossil doesn't just settle the debate. It flips decades of T. rex research on its head," says Lindsay Zanno, associate research professor at North Carolina State University and head of paleontology at the North Carolina Museum of Natural Sciences.

Distinct traits, including longer arms, a greater number of teeth, fewer tail vertebrae, and unique skull nerve structures, all appeared early in development and are biologically inconsistent with T. rex.