T. rex ancestors crossed from Asia to North America via land bridge 70 million years ago, says study

A new study based on mathematical modeling weighs in on the fierce debate among paleontologists over the origins of the king of the dinosaurs, Tyrannosaurus rex.

​ A new study based on mathematical modeling weighs in on the fierce debate among paleontologists over the origins of the king of the dinosaurs, Tyrannosaurus rex. Read More Breaking News, Latest News and Videos | CNN