The process of change from larva to adult is called metamorphosis. Spiders are keen predators that trap insects in their webs produced as silk strands from the abdomen. These are important components of food webs and serve as human food also. The crustacean body is divided into about twenty segments, each of which bears paired specialized appendages including antennae, mandibles, maxillae, grasping claws, and legs. Insects and Their Relatives Millipedes and Centipedes Both bear numerous paired legs along the elongated trunk.
Millipedes are cylindrical, slow-moving vegetarians.
Centipedes have a more flattened body, move rapidly, and prey on small invertebrates using their fangs and venom glands.