invertebrate is an animal lacking a backbone, such as an arthropod, mollusk,
annelid, coelenterate, etc. The invertebrates constitute an artificial
division of the animal kingdom, comprising 95 percent of animal species
and about 30 different phyla. Insects, crabs, lobsters and their kin, snails, clams, octopuses and their kin, starfish, sea-urchins and their kin, ants, bess, and worms and centipedes.