Shellfish is a a broad term for various aquatic mollusks, crustaceans, and echinoderms that are used as food.
Jewish Kosher Law traditions forbid the eating of shellfish.
A practical basis for prohibitions of eating shellfish, or benefits of such a ban, could relate to health issues.
Ecologically, not only are shellfish vital in marine food chains, but some filter-feeding forms are able to purify a great amount of water and thus are crucial to the stability of marine systems.
Some interpretations of Islamic dietary laws forbid eating shellfish.
Archaeological finds have shown that humans have been making use of shellfish as a food item for thousands of years.
The book of Leviticus (11:9-12) prohibits the consumption of shellfish.
Inter-tidal herbivorous shellfish such as mussels and clams can help people reach a healthy balance of omega-3 and omega-6 fats in their diets, instead of the current Western diets (Robson 2006).
Shellfish aquaculture is a rapidly growing enterprise that helps provide a stable source of shellfish while not harming wild populations.
Some shellfish have a tendency to feed on waste or accumulate toxins or heavy metals in their tissues.
Shellfish are aquatic invertebrates that are used for food and typically either have a hard exterior or an exoskeleton, or belong to a group of invertebrates that typically are characterized by such shells.
The two most common groups of invertebrates associated with the term shellfish are mollusks and crustaceans.
Shellfish provide important culinary, economic, and ecological values.
Sushi (vinegared rice, topped with other ingredients, including shellfish, fish, meat, and vegetables), feature both raw and cooked shellfish.
On occasion, the word shellfish is used to refer only to edible marine molluscs, and then shrimp, crab, or lobster are not included in the category (MDOT 2008).
The word "shellfish" is used as singular and plural, but the less common plural "shellfishes" is sometimes used when referring to various "types of shellfish" (Festing 1999).