Domain: Eukarya ; Kingdom: Animalia (Vertebrates) Phylum Chordata – Subphylum Urochordata – Subphylum Cephalochordata – Subphylum Vertebrata – Superclass Agnatha – Superclass Gnathostomata I – Class Chondrichthyes – Class Osteichythyes – Superclass Gnathostomata II – Class Amphibia – Order Urodela – Order Anura – Order Apoda – Class Reptilia – Order Chelonia – Order Squamata – Order Crocodilia – Class Aves – notochord; dorsal, hollow nerve cord; pharyngeal slits; muscular post-anal tail chordate without a backbone (tunicate) notochord, dorsal hollow nerve chord, gill slits, and tail in adult stage (4/4 = lancelet) neural crest; pronounced cephalization; vertebral column; closed circulatory system jawless vertebrate lampreys and hagfishes the jawed fishes cartilaginous endoskeleton reinforced by calcified granules sharks and their relatives bony endoskeleton, operculum, swim bladder ray-finned fishes and lobe-finned fishes the jawed tetrapods rudimentary lungs, dependence on water for reproduction frogs, toads, salamanders, caecilians urodeles (salamanders) anurans (frogs and toads) apodans (legless caecilians) amniotic vertebrates paraphyletic clade hardened shell (turtle and tortoise) forked tongue (snaks and lizards) unique jaw (crocodiles and alligators) birds probably began as flying reptiles amniotic eggs and feathers ratites (flightless), carinates (carina), Passeriformes (fly and perch) hair, endothermic metabolism, 4-chambered heart, mammary glands monotreme (egg), marsupial (pouch) eutherian (placenta) elephant platypus, echidna manatee, dugong dog, wolf, bear, cat, weasel, otter, seal bat sheep, pig, cattle, deer, giraffe whale, dolphin, porpoise horse, zebra, tapir, rhinoceros squirrel, beaver, rat, porcupine, mouse some moles, some shrews kangaroo, opossum, koala sloth, anteater, armadillo rabbit, hare, pica
Class Mammalia –
Order Proboscidea – Order Monotremata – Order Sirenia – Order Carnivora – Order Chiroptera – Order Artiodactly – Order Cataceans – Order Perissodoctyla – Order Rodentia – Order Insectovora – Order Marsupialia – Order Edentata – Order Lagomorpha –