First of all it is not group, it is order. It is the Suarischia and the Ornithischia.
The two major groups of dinosaurs are the Saurischia (lizard-hipped dinosaurs) and the Ornithischia (bird-hipped dinosaurs). These groups are distinguished by differences in their pelvic bone structure.
TWO
Dinosaurs are classified as Animalia, Reptilia.
the two original groups were Animal and Plant signed, Kaguya Kaze
The two orders of the Superorder Dinosauria are Saurischia and Ornithischia, meaning the lizard-like pelvic girdle and the bird-like pelvic girdle. The classification is a little strange in that the birds are almost certainly descended from the Saurischia.
Archeobactetia
Yes There is the bird-hipped dinosaurs and the reptile or lizard-hipped dinosaurs. These were further subdivided into smaller groups.
No. Dinosaurs and alligators (crocodilians) are two separate groups of archosaurs. They are related but dinosaurs are not "advanced" alligators. And evolutionarily it makes no sense to say an animal "just developed."
The classification of organisms is a system of arranging the organisms into groups or sets on the basis of similarities and differences. The two types of classification are:- (i) plant kingdom (ii) animal kingdom
The philosopher Aristotle's system of classification had two main groups: animals and plants. He further divided these into smaller categories based on shared characteristics and traits.
Carolus Linnaeus developed the first widely accepted system of biological classification. He classified organisms into two groups - plants and animals - based on their physical characteristics.
Two organisms of a family also belong to the same order, class, phylum, and kingdom in the taxonomic classification system.