Gastropods are a class of animals which have no backbone. In most but not all cases gastropods have a shell, which is created by the mantle. Gastropods are commonly known as snails and slugs. They live in the oceans, on land and in freshwater.
This taxonomic class of invertebrate animals with the scientific name Gastropoda is the largest and most successful class within the mollusks, having 60,000–75,000 named living species, and being second only to the insects in terms of diversity and in terms of the number of named species within one class of animals. Living species of gastropods range in size from adult animals that are less than one millimeter (0.039 in) in length, to a few species that are almost a meter (39.4 in) in length.
Scientists who study gastropods (or other mollusks) are known as malacologists. 2,400 years ago, Aristotle, in his History of Animals, wrote about the sea snails from which the dye Tyrian purple is extracted; the genus Murex still bears the name he used. Many gastropods are important food sources, others have human relevance in other ways, ranging from their shells being used as a source of mother of pearl through to their being vectors for several diseases.
Aquamarine or sea green is used on this portal because gastropods first evolved in the oceans, colonized both land and freshwater habitats, and need the presence of water or water vapor in order to be active. The image which is currently the icon for the gastropod portal shows an individual of Helix pomatia, an air-breathing land snail which is well known to gourmets in the Western world because it is one of the European species that is eaten as escargot.