[ad_1] There are two groups of bilaterally symmetrical animals: protostomes and deuterostomes. Protostomes contain arthropods, molluscs, and more, while deuterostomes include echinoderms and vertebrates. Protostomes are divided into three superphyla: Lophotrochozoa, Edcysozoa, and Platyzoa. Lophotrochozoans have a lophophore and include marine animals, while platyzoans are flat animals with a diminished coelom. Ecdysozoans molt their exoskeletons […]