How old were the Dinosaurs? Of course this question is related to most of the other mysteries about Dinos; how they procured food, how fast they grew and that thorny question of how many of the Dinosaur names actually indicate different Dinos and not just older or younger members of the same species. I assumed until recently that Dinosaurs grew so big because they lived a long time. I knew that some reptiles still with us today grow larger the longer they live. I’ve heard of crocodiles that are thought to be at least a hundred years old and turtles that are 200+ years old. I even wondered that perhaps in an ideal environment (as Dinosaurs appear to have lived in) they might have lived even longer. However, it seems that many Dino species can no longer be thought of as “cold blooded”, which makes them a little more different than some living reptiles.. I heard about a study of Dino growth patterns conducted by Gregory Erickson (of FSU, I think he is on a lot of TV shows) showing that Dinos had a “sigmoidal” pattern of growth, meaning that it looks s-shaped on a chart. This is like many other animals, including humans. A “teenage growth spurt” is not what I expected in Dinosaurs. According to the study, T-Rex grew about 5 pounds a day during the “spurt” but reached full height by the early 20s. Even Sue, the biggest Tyrannosaurid (and also the oldest), is supposed to only be about 30 years old. Erickson likened T-Rex to James Dean, “He lived fast and died young”. Other Dinos show the same sigmoidal pattern, including Apatosaurus (the most extreme), Maiasaura and even the small Psittacosaurus. Any thoughts?