TWENTY-ONE
Emergent Reptiles
their divergence and the appearance of
mammals
adapted from Biology, 2015, 10th Edition, pp. 688-697.
(subphylum) VERTEBRATES
(class) jawed fishes
(class) cartilagenous fishes
(class) bony fishes
lobe-finned fishes
(superclass) tetrapods
(class) reptiles
tiktaalik - transitional - 375 mya
(class) amphibians
(clade) amniotes
(subclass)
DIAPSIDS
(subclass)
SYNAPSIDS
skull temporal bone openings
double pair
single pair
ANAPSIDS
(order) testudines:
turtles, tortoises
temporal bone openings
lost
(superorder) lepidosaurs
(order) squamates:
snakes, lizards
(superorder) ichthyosaurs:
mesozoic marine reptiles
(superorder) archosaurs
(order) crocodilia
pterosauria (extinct):
mesozoic flying reptiles
saurischia (extinct)
mesozoic dinosaurs:
tyrannosaurus rex
ornithischia (extinct)
mesozoic dinosaurs:
triceratops
BIRDS
THERAPSIDS:
e.g., lycaenops,
a small predator during the late Permian period
(extinct)
MAMMALS
hair, mammary glands, endothermy
monotremes
(prototheria)
egg-laying.
platypus
marsupials
(metatheria)
pouch.
kangaroo
eutheria
well-developed placenta
vivipary

(class) jawless fishes