[Rockhounds] Here's exactly how T. rex grew from a slender tot into a massive carnivore

[Kreigh Tomaszewski]

*Tyrannosaurus rex*
<https://www.livescience.com/23868-tyrannosaurus-rex-facts.html> wasn’t
born the massive beast known for ripping prey to shreds. A paleontologist
has found the beast goes through 21 distinct growth stages as it develops
from a wee, slender tot to a full-grown, massive dinosaur king. And the two
most important stages on its growth chart occurred when *T. rex* became a
teenager and around its 18th birthday.

The study — the most comprehensive to date focused on *T. rex* growth —
also revealed: The male and female skeletons look exactly alike; the
controversial *Nanotyrannus* is not a separate species; and adult *T. rex*'s
size and weight are not predictive of its age.

Paleontologist Thomas Carr spent about three years studying 44 different T.
rex skeletons being stored at natural history museums across North America.
It was a laborious but rewarding scrutiny of the *hypercarnivore*
<https://www.livescience.com/53466-carnivore.html>, which lived from about
67 million to 65 million years ago, at the end of the *Cretaceous period*
<https://www.livescience.com/29231-cretaceous-period.html>, he said.

https://www.livescience.com/tyrannosaurus-rex-size-age.html