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How fast did dinosaurs grow, and how long did they live?

Until recently, paleontologists could only guess the maturity rate and lifespan of dinosaurs. Recent research involving microscopic analyses of the cellular structure of dinosaur bone has revolutionized our answers to these mysteries. Dinosaur bones contain growth rings, somewhat like the rings in tree trunks, which reveal yearly periods of rapid and slow growth. These studies, done in conjunction with paleontologists at AMNH, document that that Tyrannosaurus, which attained a weight of more than 10,000 pounds as an adult, reached sexual maturity at about 20 years of age and lived for up to 28 years. Created by American Museum of Natural History.

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Video transcript

Just like groups of mammals, different dinosaurs lived and grew at different rates. All of our knowledge that we have about how fast dinosaurs grew, and how long that they lived, is really group dependent, depending on group of dinosaurs it is. Some of our best evidence comes from Tyrannosaurus, and Tyrannosaurus that we know that they reached adult size in seventeen years or around seventeen years. In the oldest member of Tyrannosaurus Rex that we know, the Sue specimen in Chicago which is just a little bit over twenty five years old. Obviously our sample is very small so it's highly likely that Tyrannosaurus lived longer than that, we just don't have the samples to show it.