Invertebrates are animal species that do not develop a vertebral column. This in effect includes all animals apart from the subphylum Vertebrata.
Familiar examples of invertebrates include insects, worms, clams, crabs, octopus, snails and starfish. Taxonomically speaking, "invertebrate" is no more than a term of convenience. The vast majority of animal species are invertebrates, because only about 3% of animal species include a vertebral column in their anatomy.
Marine invertebrates are multicellular animals that inhabit a marine environment and are invertebrates, lacking a vertebral column. In order to protect themselves, they may have evolved a shell or a hard exoskeleton, but this is not always the case.
As on land and in the air, invertebrates make up a great majority of all macroscopic life in the sea.
Click on any of the images below to view our Invertebrates gallery.