Cockles are the family Cardiidae of bivalve molluscs.
The rounded shells are symmetrical, heart-shaped and feature strongly pronounced ribs. The mantles has three apertures (inhalant, exhalant, and pedal) for siphoning water and for the foot to protrude. Cockles typically burrow using the foot and feed by siphoning water in and out, sifting plankton from it. They are also capable of 'jumping' by bending and straightening the foot. Unlike most bivalves, cockles are hermaphroditic and reproduce quickly.