Ideas, Inventions And Innovations
2.5 Billion Tyrannosaurus Rexes Roamed North America over a Period of 2.5 Million Years Over approximately 2.5 million years, North America likely hosted 2.5 billion Tyrannosaurus rexes, a minuscule proportion of which have been dug up and studied by paleontologists, according to a UC Berkeley study.
Image by Julius Csotonyi, courtesy of Science magazine
How many Tyrannosaurus rexes roamed North America during the Cretaceous period?
That’s a question Charles Marshall pestered his paleontologist colleagues with for years until he finally teamed up with his students to find an answer.
What the team found, to be published this week in the journal Science, is that about 20,000 adult T. rexes probably lived at any one time, give or take a factor of 10, which is in the ballpark of what most of his colleagues guessed.
T. rexes walked the Earth during its existence, reports Karina Shah for
New Scientist. The new study was published this week in the journal
Charles R. Marshall, a University of California, Berkeley paleontologist, was fascinated with the idea of how many of the mega-predators walked the Earth whenever he held a
T. rex fossil, reports the
New York Times.
“Were there are a million, a billion, a trillion
T. rexes? Is this one in a million, one in a billion, one in a trillion? How on earth could we know that number? We all know fossils are rare, but how rare are they? And so it really started with that question,” Marshall tells the