The time zone during which the Dinosaurs lived on the earth is referred to as the Mesozoic Era and that time had begun roughly 245 million years ago from the point of time we stand at now. Dinosaurs lasted on this planet for a time period of 180 million years and this extensive time period is divided by scientists into three primary phases during which the species went through evolution and extinction. The three ages are called the Triassic Age, the Jurassic Age and the Cretaceous Age and each of these ages had difference in terms of geography, climate as well as evolution.
The Triassic Age lasted roughly for 37 million years before some sort of a mass destruction eliminated almost every living being on the planet. This was the age of the Pangaea, the one super continent which was the only mass of land, yet to be divided. The Triassic Age had dinosaurs that were not as big as the ones in the Jurassic or the Cretaceous Age, but mammal evolution began during this Age. Some of the Dinosaurs of the Triassic Age are Coelophysis, Eoraptor, Ichthyosaurs, Iguanadon and Desmatosuchus.
The Jurassic Age Lasted for 62 million years approximately and at this point of time, the dinosaurs were really getting bigger and bigger. Also, the Pangaea was forming and reforming continuously at this time. The first of the dinosaurs that resembled birds, were found during this period of time. Some of the dinosaurs that dominated the planet at the time were Allosaurus, Apatosaurus, Diplodocus, Stegosaurus and Compsognathus. Another disaster followed and marked the end of the Jurassic Age, but it was not as devastating as the previous one.
The Cretaceous Age lasted for about 81 million years, which is the largest within the Mesozoic Era. The largest of all the dinosaurs appeared during this time with the likes of the Giganotosaurus carolinii, which was the biggest carnivorious dinosaur that ever lived, even bigger than the legendary Tyrannosaurus rex. As its name suggests, when the Seismosaurus walked, it probably made the ground shake with every step that it took; it was the largest dinosaur that ever lived. As the Cretaceous Age came to an end, the entire population of the dinosaurs were wiped clean off the face of the earth and thus came the “Age of the Reptiles” to an end, 65 million years ago.