The largest-ever study of how Tyrannosaurus rex grew shows a much longer, slower path to adulthood than scientists previously thought. For decades, scientists have been counting annual growth ...

Tyrannosaurus rex may have taken far longer to grow up than scientists once thought. By analyzing growth rings in fossilized leg bones from 17 tyrannosaur specimens and using new statistical methods, ...

For decades, scientists have been counting annual growth rings—similar to tree rings—inside fossilized leg bones of Tyrannosaurus rex to estimate how old the giant carnivores were when they died and ...