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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 !! !Common Characteristics: "
!notochord, pharyngeal gill slits, hollow dorsal nerve cord!Sub-phylum: Vertebrata!! !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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Total Animal Species: 1,367,555!
Total Vertebrate Species: 62,305 (4.5%)!
Overview of Vertebrate Classes!
!Jawless Fishes – !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 – !Ø aquatic vertebrates!
Ø pharyngeal gills!
Ø skeleton made of cartilage !
Examples - sharks, rays, skates!
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Overview of Vertebrate Classes!
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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 !! !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!
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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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Overview of Vertebrate Classes!
Great Transformations: Important Evolutionary Advances!
Jaws- Fish!• The first fishes to be found in abundance in the fossil record were
jawless. These are limited to eating small particles of food by filter-feeding and vacuum suction.!
• 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!
• Development of 4 limbs from existing fins.!
• The first amphibians had strong limb bones and girdles for movement unsupported by water.!
• The ribs formed a cage that supports and protects the internal organs. !
• Adult amphibians have more mobility and habitat availability!
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Eggs- Reptiles!• Reptiles evolved from amphibians when climatic changes caused
loss of amphibian habitat. !• Reptilian eggs are surrounded by a shell and several membranes that
create a protected environment for the embryo. !
• These “amniotic eggs” contain nutrient-rich yolk used by the embryo for food.!
!Internal Temperature Control- Birds and Mammals!• Fish, amphibians and reptiles are ectothermic. The have an internal
body temperature that varies with external (environmental conditions) due to a slow metabolism.!
• Birds and mammals are endothermic. They maintain a relatively high and constant internal body temperature that is regulated internally due to a fast metabolism.!
• This adaptation is very important for animals living in habitats where temperatures and seasons are variable.!
• Requires significantly more energy/food.!
Iguana Polar Bear
Penguin