By identifying characteristics of each animal group, students will make connections about what the groups have in common and what distinguishes them from each other. Background This activity centers on the five major vertebrate classes: fish, amphibian, reptile, bird, and mammal. These classes have things in common, but also have features that separate them into the different groups. This activity encourages students to think of the similarities and differences between the groups, as well as considering how these characteristics contribute to the animals’ survival within a particular environme Duration: 60 Minutes.