ClamClams are invertebrates, with a two piece shell that is joined together to form a hinge. They burrow into the sand, and can extrude a foot to enable them to move. They use a tube-like siphon to draw in water, which they extract oxygen from and filter for the plankton that is their food source. Humans are not the only ones to find them tasty; birds, eels, and other sea life are predators. There are over 15,000 different species of clams.This image is copyright and may not be used without specific authorization. Permission is explicitly denied for Pinterest.