Pteropods: Swimming snails of the sea

The pteropods are a fascinating group of snails that spend their entire lives swimming or drifting in the ocean and never touching the bottom. Pteropoda means wing-foot referring to their muscular foot that has evolved into a pair of wings allowing them to take advantage of the Earth’s largest habitat, the open ocean. There are two distinct types of pteropods – those with shells and those without. The shelled pteropods produce a net of sticky mucous to passively collect and eat marine snow. The pteropods w