Class
Cephalochordata
Agnatha
Chondricthyes
Osteichthyes
Examples
Amphioxus (lancelet)
Jawless fish (Hagfish, Lamprey)
Cartilagenous fish (shark, rays,
skates)
Bony fish (perch, clownfish)
Vertebrates; Endoskeleton made
Fish-like invertebrates; no internal Vertebrates; cartilagenous skull; 2Characteristics
of cartilage; 2-chambered heart;
skeleton; no heart; ectothermic
chambered heart; ectothermic
ectothermic; fins
Class
Examples
Amphibia
Frogs, salamanders, toads
Land/water vertebrates;
ectothermic; 3-chambered heart;
Characteristics cutaneous respiration; "soft" eggs;
larva/adult stages
(metamorphosis)
Reptilia
Vertebrates; Endoskeleton made
of bone; swim bladder; moveable
fins; 2-chambered heart;
ectothermic
Aves
Mammalia
Snakes, turtles, alligators,
crocodiles
Birds (chicken, eagle)
Monotremes (duck-billed platypus
& spiny anteater), Marsupials
(kangaroo, koala, etc.), and
Eutherians (dogs, cows, humans)
Mostly land vertebrates; 3chambered heart (except
crocodiles); internal fertilization;
amniotic eggs
Land vertebrates; endothermic;
feathers; hollow bones; amniotic
egg; four-chambered heart
Vertebrates; endothermic;
mammary glands; hair/fur; 4chambered heart