Dinosaurs.

Dinosauria (gr. "terrible lizards") is a dinosaur or superorden of vertebrate animals that dominated ecosystems during the Mesozoic, some 160 million years, reaching a wide variety and huge sizes in general. One of its main features was that possessed distinguishable legs below the body, such as mammals, and not the sides, like most reptiles. During recent years evidence has accumulated to indicate that very small carnivorous dinosaurs gave rise to birds during the Jurassic period. Hence, currently, the birds are classified within Dinosauria. Dinosaurs are often confused with other types of ancient reptiles, such as winged pterosaurios the terápsidos pelicosaurios and aquatic ictiosaurios, plesiosaurios and mosasaurios, although none of these were actually dinosaur.

Dinosauria is a superorden of the class of sauropsids. Are considered as a taxonomic group to present a series of clear synapomorphies that unite them, such as the femur articulated with the pelvis via condyle, in respect of that angle, and hole in the pelvis. This is the same provision is in mammals, and that allows the rear legs supporting the body acting as pillars, which have a critical impact on driving ability. Dinosaurs are traditionally classified according to the structure of your hip.