Dinosaurs thrived on the Earth for 180 million years. Since their extinction mammals have ruled the world for just 65 million years. Together with other reptiles, dinosaurs lived in almost every available habitat and evolved into thousands of different forms. For these reasons they must be considered an extremely successful biological experiment. The experiment eventually failed only because these animals could not adapt quickly enough when conditions on Earth suddenly changed. It is interesting to speculate on how dinosaur might have developed if these mass extinctions had not taken place. Possibly they could have evolved to parallel the ways that modern mammals have developed.
Picture credit: google
