2.5 Billion T. Rex Roamed Earth, but Not All at Once, Study Says
Voice of America
One Tyrannosaurus rex seems scary enough. Now picture 2.5 billion of them. 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 generations, according to a study in Thursday’s journal Science. It’s a first-of-its-kind number, but just an estimate with a margin of error that is the size of a T. rex. “That’s a lot of jaws,” said study lead author Charles Marshall, director of the University of California Museum of Paleontology. “That’s a lot of teeth. That’s a lot of claws.” The species roamed North America for about 1.2 million to 3.6 million years, meaning the T. rex population density was small at any one moment. There would be about two in a place the size of the Washington, D.C., or 3,800 in California, the study said.Hannah Gutierrez-Reed, center, prepares for a sentencing hearing in state district court in Santa Fe, New Mexico, April 15, 2024. (Eddie Moore/The Albuquerque Journal via AP, Pool) FILE - A musician plays a violin behind a photograph of cinematographer Halyna Hutchins during a vigil in her honor in Albuquerque, New Mexico, Oct. 23, 2021.
Performers take part in the final dress rehearsal of the flame lighting ceremony for the Paris Olympics, at the Ancient Olympia site, Greece, April 15, 2024. Actress Mary Mina, playing a priestess, hands an olive branch to the first torch bearer, Greek olympic gold medalist Stefanos Douskos, during the final dress rehearsal of the flame lighting ceremony for the Paris Olympics at the Ancient Olympia site, Greece, April 15, 2024. Actress Mary Mina, playing a priestess, lights the flame during the final dress rehearsal of the flame lighting ceremony for the Paris Olympics, at the Ancient Olympia site, Greece, April 15, 2024. Performers take part in the final dress rehearsal of the flame lighting ceremony for the Paris Olympics, at the Ancient Olympia site, Greece, April 15, 2024.
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