We classify animals into two main groups. Invertebrates are animals without backbones, such as spiders, insects, and clams. Vertebrates are animals with backbones. In this movie, you’ll explore different groups of vertebrates such as mammals, birds, fish, amphibians, and reptiles. You'll find out about different warm-blooded and cold-blooded animals. Which animals lay eggs? Which animals get milk from their mothers? Watch the movie to find out!