Vertebrate Characteristics
Taxonomy Review!
Taxonomy- classifying organisms based on common characteristics and
assigning each organism a universally accepted name.!
Kingdom, Phylum, Class, Order, Family, Genus, Species – In order from most
general to most specific!
Phylum = Chordata; Sub-phylum = Vertebrata!
Classes = Agnatha (jawless fish); Osteictheyes (bony fish); Chondrictheyes
(cartilage fish); Amphibia (amphibians); Reptilia (reptiles); Aves (birds);
Mammalia (mammals)!
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Carolus Linnaeus!
Classification of Vertebrates!
Phylum: Chordata !
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!Common Characteristics: "
!notochord, pharyngeal gill slits, hollow dorsal nerve cord!
Sub-phylum: Vertebrata!
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!Common Characteristics: "
!backbone that supports and protects spinal cord, endoskeleton, distinct
!head with skull and brain!
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Lancelet
Tunicate
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Overview of Vertebrate Classes!
Total Animal Species: 1,367,555!
Total Vertebrate Species: 62,305 (4.5%)!
Overview of Vertebrate Classes!
Jawless Fishes – !
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u  aquatic animals with pharyngeal gills !
u  retain larval notochord into adulthood !
u  skeleton is made of cartilage !
Examples – lamprey, hagfish."
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Overview of Vertebrate Classes!
Cartilage Fishes – !
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Ø  aquatic vertebrates!
Ø  pharyngeal gills!
Ø  skeleton made of cartilage !
Examples - sharks, rays, skates!
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Overview of Vertebrate Classes!
Boney Fish/Ray-Finned Fish – !
v  aquatic vertebrates with pharyngeal gills!
v  skeleton composed of bone and covered by scales!
v  fins for movement!
!Examples: salmon, angel fish, trout, perch!
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Overview of Vertebrate Classes!
Amphibians – !
q  vertebrates that are aquatic as larvae and
terrestrial as adults !
q  breathe with lungs as adults !
q  have four legs !
q  have moist skin and lack scales !
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!Examples – frog, salamander, axolotl."
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Overview of Vertebrate Classes!
Reptiles – !
ü  Vertebrates with scaly skin !
ü  have lungs and live entirely on land!
ü  shelled egg with specialized (amniotic) membranes !
Example – snake, Komodo dragon, turtle.!
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Overview of Vertebrate Classes!
Birds – !
²  endothermic vertebrates with feathers, !
²  two legs used for walking and perching!
²  two wings that lack claws !
!Example – pigeon, hawk, eagle; bird of paradise.!
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Overview of Vertebrate Classes!
Mammals – !
o  endothermic animals with fur or hair !
o  mammary glands produce milk to nourish young!
o  most have placenta to nourish fetus!
!Example – human, whale, pig, bat, anteater!
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Great Transformations: Important Evolutionary Advances!
Jaws- Fish!
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The first fishes to be found in abundance in the fossil record were
jawless. These are limited to eating small particles of food by filterfeeding and vacuum suction.!
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Jaws in fishes made it possible for them to eat plants and other
animals and defend themselves by biting. !
Quadrapedal Skeleton/Strong Bones - Amphibian Adults!
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Development of 4 limbs from existing fins.!
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The first amphibians had strong limb bones and girdles for
movement unsupported by water.!
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The ribs formed a cage that supports and protects the internal
organs. !
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Adult amphibians have more mobility and habitat availability!
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Eggs- Reptiles!
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Reptiles evolved from amphibians when climatic changes caused
loss of amphibian habitat. !
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Reptilian eggs are surrounded by a shell and several membranes that
create a protected environment for the embryo. !
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These amniotic eggs contain nutrient-rich yolk used by the
embryo for food.!
!Internal Temperature Control- Birds and Mammals!
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Fish, amphibians and reptiles are ectothermic. The have an internal
body temperature that varies with external (environmental
conditions) due to a slow metabolism.!
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Birds and mammals are endothermic. They maintain a relatively
high and constant internal body temperature that is regulated
internally due to a fast metabolism.!
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This adaptation is very important for animals living in habitats
where temperatures and seasons are variable.!
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Requires significantly more energy/food.!
Iguana
Polar Bear
Penguin
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