Dinosauria
Dinosauria is a clade consisting of all descendants of the last common ancestor of the Saurischia and Ornithischia, two major groups of dinosaurs. This group encompasses a diverse array of species that inhabited the Earth during the Mesozoic Era, ranging from large herbivores to agile carnivores. As a part of Fossil Vertebrates and Reptiles, Dinosauria represents some of the most advanced and specialized forms of these ancient creatures. Within the broader category of Dinosaurs, Dinosauria specifically refers to those species that are characterized by their distinct skeletal structures, which include features such as the presence of a pubis that points backwards and an elongated tail for balance. This clade is crucial for understanding the evolutionary history of not only dinosaurs, but also birds, as many avian characteristics can be traced back to this group.