Era: Jurassic - Cretaceous
Geographic Age: 150 mya
Description: Bivalves have no head, and they also lack a radula. They include clams, oysters, cockles, mussels, scallops, and numerous others that live in saltwater, as well as some families that live in freshwater. The majority are filter feeders. The gills have evolved into ctenidia, specialized organs for feeding and breathing. Most bivalves bury themselves in sediment, where they are relatively safe from being attacked. Others lie on the sea floor or attach themselves to hard surfaces like rocks. Some bore into stone, clay or even wood and live inside. A few types of bivalves, like scallops, can swim.
The shell of a bivalve is made of calcium carbonate, and consists of two, usually similar, parts called valves. These are bound together along one edge (hinge line) by a flexible ligament, usually with interlocking “teeth” on each of the valves, forms the hinge. This arrangement allows the shell to be opened and closed without the two halves detaching.
Size approximately: 70mm x 50mm x 30mm
Quantity: 1 piece