Virtually evolved to rule the ancient landscape, though with pathetically small arms that were able to lift a few hundred pounds. It was the popular perception for them until a paleontologist found small skeletons and assumed it was the 6-foot tall T.Rex skeletons' pygmy species.
As usual, science has its surprises, and these small T.Rexes were not pygmy species as initially assumed. This duo of small carnivores were just teenagers, that have not reached their full growth potential as alpha predators. So, chalk up the pygmy rex as another hypothesis thrown out the window. One reason, this does not work is that evidence has contradicted it.
Dino detectives have found evidence that the 6-feet dinosaurs that were found in Montana, during the early 2000s were just teenagers. Their estimated ages when they perished were between 13-15 years old, and they are not a Nanotyrannus as originally assumed.
The pair of tyrannos was affectionately named "Jane" and "Petey" who never survived into adulthood. Life for young tyrant lizards was hard, and they faced dangers from their kind as well. Bigger older tyrannosaurus rex is likely to kill younglings if there was no readily obtainable food source.
Most T. Rex younglings were always hiding and generally avoiding the bigger plant-eaters, and most especially their bigger counterparts. Reaching teenager status is not easy, "Jane" and "Petey" beat the odds well but not enough. As their skeletons are preserved in the rock for millions of years, give a clue to dino detectives as to what life was 65 MYA a long time ago.
Literally terrible teens
One method by which the age of bones is predicted is by looking at it with a microscope. These leg bones have visible signs that indicate how much weight they carried when the animals were alive. Working out this problem by dino-detectives is like looking at tree rights. These rings in the bone are either thick or thin, as an indication of how much food is available. Compared to the young ones, most adult T. Rex have normal bone tissue.
Examining the leg bones of Jane and Petey, they judged by the rings in the bone their exact ages. These annual rings in the leg bones of Jane, which is almost complete by the way, is about 13-years at the time of death. While Petey was not so complete, found farther away is 15-years when he perished. Another evidence revealed when they died is the remains were all-over and laid out quickly too.
The Tyrant lizard king becomes an adult
One difference of T. Rex adults is they are not as thinner or lightly built, compare to sleeker juvenile tyrant lizards. Another difference that dino-detectives have noticed is younger tyrannos have lateral-compression in their teeth and more jagged like knives too. The monstrous bite of a big T. Rex was reached when they reached adult ages.
If big ones crush with their jaw, smaller and younger animals bit and serrated flesh better from the fossilized evidence. This indicated different prey items as they got bigger and meaner, alpha predators will eat everything is normal. Still, juvenile T.Rexes like jane and Petey hide more secrets, as these 6-foot tall T.Rex skeletons are studies there might be more secrets to learn from them.
Related Article: 6-Foot-Tall T. Rex Skeletons Not a New Pygmy Species, Just Teenagers
