WASHINGTON (Reuters) — Large meat-eating dinosaurs attained their great size through very different growth strategies, with some taking a slow and steady path and others experiencing an adolescent growth spurt, according to scientists who analyzed slices of fossilized bones.
The researchers examined the annual growth rings — akin to those in tree trunks — in bones from 11 species of theropods, a broad group spanning all the big carnivorous dinosaurs including Tyrannosaurus rex and even birds.
Sue inhabited South Dakota about a million years before dinosaurs and many other species were wiped out by an asteroid impact 66 million years ago.
"Theropod dinosaurs represent the largest bipedal animals to have ever lived and were also the dominant predators in terrestrial ecosystems for over 150 million years — more than twice as long as mammals have been dominant," added University of Minnesota paleontologist and study coauthor Peter Makovicky
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