1. Education

Invertebrates

There are thousands of invertebrates in the oceans. Invertebrates are commonly defined as an animal without a spine. Here you can learn more about invertebrates, and read facts and view images of many kinds of marine invertebrates.
  1. Arthropods - Crabs, Lobsters and More (10)
  2. Cnidarians - Corals, Jellyfish, Anemones (7)
  3. Echinoderms - Sea Stars, Urchins and More (3)
  4. Mollusks - Phylum Mollusca (13)

What Is An Invertebrate?
A common definition of invertebrate is "an animal without a backbone, or spine." But the more correct definition is an animal without a notochord. A notochord is a rigid rod made of cartilage that is present in all chordates. Here you can learn what invertebrates look like, where they are found, and more.

Sea Mouse
Learn about the sea mouse, a type of worm.

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