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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

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