Subphylum Invertebratae

A colorful sea anemone

When you think about animals, do you picture sponges, worms, corals, clams, spiders, or starfish? All of these animals have one thing in common: they lack a backbone, or spine. The subphylum invertebratae includes many animals that are incredibly important in the world around us. You will learn about this subphylum, including sponges, cnidarians, worms, mollusks, arthropods, and echinoderms in this topic.

Essential Questions

  • What are the common characteristics of animals?
  • What are the different phyla of invertebrate animals?