This 3-page paper discusses the phylogeny of the animal kingdom showing how major groups are related including a detailed representation of the deuterostomes (echinoderms, urochordates, cephalochordates, agnathans and gnathostomes). It also examines how early zoolologists classified the echinoderms and the enidarians together in one Phylum, the Radiata, because of their radial symmetry and explain why ...