Both cephalopods and banana slugs are molluscs. Albacore are pelagic predators that eat a variety of foods, including fish, crustaceans, and cephalopods. The Humboldt squid's diet consists mainly of small fish, crustaceans, cephalopods, and copepods. Bony fish and fish eggs, cephalopods, and crustaceans are taken as food. Gastropod fossils may sometimes be confused with ammonites or other shelled cephalopods. It also consumes cephalopods and crustaceans, including decapods and isopods. They include fish, crustaceans, and cephalopods. Nacre is found in some of the most ancient lineages of bivalves, gastropods, and cephalopods. They eat an array of fish, bottom-feeding prawns, cephalopods and crustaceans. An endoskeleton derived from the mesoderm is present in echinoderms, sponges and some cephalopods. Common zooplankton include copepods, krill, jellyfish, siphonophores, larvaceans, cephalopods, and pteropods. This species preys on cephalopods, bony fishes, and smaller sharks. Killer whales hunt varied prey including fish, cephalopods, mammals, sea birds, and sea turtles. Cuttlefish, like other cephalopods, have sophisticated eyes. Natural predators include sharks and predatory cephalopods.