This lifeform is found widely in Eurasia. This lifeform is widespread in North America. This lifeform has been extinct for over 20,000 years.

Armored Dinosaurs (Sub-Order Ankylosauria) contains species that could be loosely described as flat-footed reptiles. Some of the species remind one of hunchbacked hoof-like crocodiles. Others had armor covering their backs.

Bird Hipped Dinosaurs (Order Ornithischia) contain several unusual small dinosaurs plus several large dinosaurs that are familiar to the general public. These are usually divided into four different Sub-orders: Ornithopodia, Stegosauria, and Ankylosauria, and Ceratopsia.

(Some scientists would place the living birds in some close relationship to this group.)

Reptiles (Class Reptilia) are an ancient group of scaled  chordates. These scales may be permanently joined, as in the  turtles, or flexible, as in the snakes. Reptiles are land-based. Their eggs are laid on land and the young are air breathing.

Backboned Animals (Phylum Chordata) are the most advanced group of animals on earth. These animals are characterized by having a spinal cord or backbone. Most members have a clearly defined brain that controls the organism through a spinal cord. Fish, amphibians, reptiles, birds, and mammals are in this phylum.

Currently, some taxonomists believe that the fish should be divided into two groups (sharks and regular fishes) and that there are some other primitive groups in the phylum such as hagfish or lampreys.

Animal Kingdom contains numerous organisms that feed on other animals or plants. Included in the animal kingdom are the lower marine invertebrates such as sponges and corals, the jointed legged animals such as insects and spiders, and the backboned animals such as fish, amphibians, reptiles, birds, and mammals.