A new analysis of fossils believed to be juveniles of T. rex now shows they were adults of a small tyrannosaur, with narrower jaws, longer legs, and bigger arms than T. rex. The species, Nanotyrannus ...

Tyrannosaurus rex might have been the “tyrant lizard king,” but before the mighty T. rex stomped across what is now North America, it ancestors weren't exactly living like royalty: They were tiny, ...