Abundant and easily harvested in large numbers in inter-tidal zones, bivalves (clams, oysters, mussels, scallops, and many other species with paired, hinged shells filled with a meaty body) are a reliable, nutritious and extremely important food source for many coastal cultures.
Bivalves are marine mollusks and include species of cockles, mussels, oysters, scallops, clams. They all have a soft body, with no paired or jointed limb, that is contained within a two-valve shell, which is articulated by a hinge plate and adductor muscles. The body is attached inside each valve along a visible line, but a siphon and foot can extend outside the shell and the body cavity is filled by large gills.