DALLAS — Scientists once thought of dinosaurs as sluggish, cold-blooded creatures. Now, a new study estimates that the first warm-blooded dinosaurs may have roamed the Earth about 180 million years ago, about halfway through the creatures’ time on the planet. Warm-blooded creatures — including birds, who are descended from dinosaurs, and humans — keep their body temperature constant whether the …
One Tyrannosaurus rex seems scary enough. Using calculations based on body size, sexual maturity and the creatures' energy needs, a team at the University of California, Berkeley figured out just how many T. rex lived over 127,000 generations, according to a study in Thursday's journal Science. The species roamed North America for about 1.2 million to 3.6 million years, meaning …
One Tyrannosaurus rex seems scary enough. That’s how many of the fierce dinosaur king probably roamed Earth over the course of a couple million years, a new study finds. Using calculations based on body size, sexual maturity and the creatures’ energy needs, a team at the University of California, Berkeley figured out just how many T. rex lived over 127,000 …
