Iguana family is primarily found in the New World with several  species being found in the United States. Madagascar, Fiji, and  the Friendly Islands also have representatives. The American  Chameleon, not related to the Old World Chameleon, is a small,  but typical, example of this family.

Lizards and Snakes (Squamata Order) share many common characteristics and consequently they are grouped in a single order. There are greater differences between some groups of lizards than there are between other groups of lizards and snakes. The same is true of snakes. Lizards and snakes share a common skull shape.

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.