KINGDOM ANIMAL• PHYLUM: CHORDATA–SUBPHYLUM: VERTEBRATA

VERTEBRATES

ANIMALS WITH:Dorsal nerve cordHollow backbone

Ventral heart

5 major classes• Classified by:– Skin covering– Heart chambers– Reproduction– Type of limbs– How they maintain body temperature

HOMOLOGOUS STRUCTURESshow relationships

ChondrichthyesSharks, rays

• Skin covering: teeth• Two chambered heart• External or internal fertilization• Limbs – fins• Cold blooded, aquatic

Skate egg capsule

For a bowl of soup, we alter the ecosystem

OstheicthyesBony fish

• ectothermic (cold blooded), aquatic vertebrates.

• skin is covered with scales.• limbs - fins for swimming.• breathe with gills.• External fertilization - lay eggs that

must be in water.

AMPHIBIANSFROGS, TOADS, NEWTS, SALAMANDERS• ectothermic vertebrates.• skin is either smooth (like a frog) or rough (like a

toad).• dependent upon moisture and subject to

desiccation; their skin must remain moist to aid in breathing

• lay eggs in water, which hatch into an intermediate life form (tadpole or larva) that usually breathes with gills, and change into the adult form that breathes air and can live outside water.

• three-chambered hearts.• lack claws on their toes.

frog

Cane toad

NEWT

RED SPOTTED NEWT

SALAMANDER

REPTILESSnakes, lizards, turtles, gators

• ectothermic vertebrates.• skin has scales, but no hair or feathers.• three-chambered hearts (except for

alligators and crocodiles, which have four-chambered hearts).

• claws on their toes • first animals, in evolution, to develop the

amniotic egg. This allows reptiles to lay eggs on land.

Amnionic Egg (shelled egg)

copperhead

rattlesnakes

Pygmy rattlesnake

BIRDS• endothermic vertebrates.• skin is covered with feathers.• four-chambered hearts.• bones are lightweight and usually

hollow.• forelimbs are modified as wings.• lay eggs.

MAMMALS• endothermic vertebrates.• Body covered with hair, which varies

greatly among species.• Most have sudoriferus (sweat) glands.• have mammary (milk-secreting) glands.• sebaceous (fat-secreting) glands.• have heterodont dentition (different types

of teeth).

Egg laying mammals

Pouched Mammals