Gastropods are snail-like and slug-like invertebrate (lacking a backbone) animals, and are types of mollusks. Snails have hard mineral shells; slugs lack shells. Because fossils mostly represent the hard parts of organisms, snails are the most common types of gastropod fossils. Slugs are not preserved as fossils. Snails have a single, coiled shell. Modern snails include some of the most common seashells on beaches today, including conch, cowrie, limpet, olive, murex, turban, turret, and whelk shells. Some snails are carnivorous predators, some are herbivores, some are detritus feeders, and others are scavengers. Different species live in fresh, brackish, and marine water. Modern gastropods mostly live on a substrate (sediment or other objects) or burrow in the substrate.
Content and graphics by Stephen Greb, Kentucky Geological Survey