Molluscs, which include snails, mussels, octopuses, and slugs (just to name a few), dominate the marine world with their successful ability to adapt and diversify. With an estimated 85,000 living species, nearly 25 percent of all marine organisms are molluscs. Sea snails, nudibranchs, and squid are all part of this animal classification, the only phylum to inhabit nearly every ecosystem, from shallow reefs to the deep sea, freshwater, and even land.

Learn how each class of mollusc has evolved adaptations, defense mechanisms, and behaviors in order to live and thrive.