Overview: A program that introduces students to some of the major differences between fish, amphibians, reptiles, birds and mammals. Students will understand the differences between vertebrates and invertebrates, and how humans fit into the environment.he level of differentiation we are going to examine in this program is the broad taxonomic classification class.. The phylum chordata (animals with backbones) is divided into five common classes: fish, amphibians, reptiles, mammals and birds.