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The Spokesman-Review Newspaper
Spokane, Washington  Est. May 19, 1883

Like James Dean: T. rex lived fast, died young

Malcolm Ritter Associated Press

NEW YORK – Think your teenager is growing fast? A new study says Tyrannosaurus rex launched into an explosive growth spurt in its teen years, packing on an average of nearly five pounds a day.

That spurt, from ages 14 to 18, let T. rex pick up most of its eventual adult weight of around six tons, the research says. It stopped growing at around age 20 and apparently died by age 30.

T. rex was “the James Dean of dinosaurs – it lived fast and died young,” said Gregory Erickson of Florida State University, one of the scientists presenting a study of the reptile’s growth pattern in today’s issue of the journal Nature.

In contrast, he said, while an African elephant’s growth reaches a plateau at around the same age and weight, that animal lives past age 50.

Scientists have long wondered how the huge dinosaurs got so big. Did they grow slowly for a long time or very quickly for a shorter period? Or was it a combination? The question must be studied separately for various kinds of dinosaurs, experts said.

T. rex was one of the largest meat-eaters ever to walk the land when it died out some 65 million years ago. At an elephant-like six tons, it stretched about 40 feet to 45 feet long and measured about 13 feet tall at the hip. The adult skull alone was five feet long, with teeth up to a foot long.

“T. rex is one of the dinosaurs that could eat a human being in probably two bites,” said Thomas Holtz Jr. of the University of Maryland. “One bite would take off the top, and the next bite would take off the hips and legs.”

Holtz, who didn’t participate in the new study, said it could help answer other questions about T. rex. For example, he said, it looks like the creature got so big after age 12 that it might not have been able to run as fast as before. So maybe it stopped running after prey and turned more to scavenging or ambushing its meals, he said.