There are several different phyla of the kingdom Animalia, the most well known are the chordates, cnidarians, arthropods, echinoderms, mollusks, round worms, and flat worms. The phyla re generally differentiated by body plans. Of these are the chordates. Animals from the phylum Chordata have had notochords, pharyngeal slits, and post-anal tails at some point in their life cycle. All chordates are eukaryotic, heterotrophic, multicellular and bilaterally symmetric organisms. Some examples of chordates are humans, lizards (shown in the picture above), and fish.