Invertebrates
Invertebrates are a diverse group of animals that includes over 30 phyla. Invertebrates do not have a backbone, nor a bony skeleton. This large group of animals includes sponges, cnidarians, flatworms, roundworms, segmented worms, molluscs, echinoderms, and arthropods. About 97 percent of all known species are invertebrates. The articles listed below provide information about the characteristics, classification and evolution of invertebrates.
What Are Invertebrates?
Invertebrates are animals that lack a backbone. In this article, we'll explore basic facts about invertebrates including how they are classified, what they eat, where they live and the characteristics that make them different from other animal groups.
Facts About Invertebrates
Learn interesting facts about invertebrates and find out about the characteristics make them different from other animal groups, their life cycle and their evolutionary history.
A Guide to Vertebrates and Invertebrates
Among the most basic criteria by which animals are sorted is whether or not they possess a backbone. This single trait places an animal into one of just two groups: the vertebrates or the invertebrates.
Invertebrate Pictures
Pictures of invertebrates, including invertebrate photos such as jellyfish, ladybugs, snails, spiders, octopus, chambered nautiluses, mantis and more.