Both lobsters and cockroaches are arthropods, making them distant relatives. An arthropod is a member of the phylum Arthropoda, which includes insects, crustaceans and arachnids. Arthropods are characterized by a jointed exoskeleton composed of chitin, a segmented body and jointed appendages.
Lobsters live in all oceans of the world. Their habitats include shorelines and the continental shelf. As omnivores, lobsters eat fish, mollusks and worms in addition to plant life. Scavenging also occurs, and cannibalism may happen in captivity. Lobsters can reach lengths of 20 inches or more, as they grow continuously throughout life. Although lobsters walk slowly on the sea floor, they are capable of quick bursts of speed by swimming backwards.