part a: classification and evolutionary relationships vertebrate classification:
TRANSCRIPT
Part A: Classification and Evolutionary RelationshipsPart A: Classification and
Evolutionary Relationships
Vertebrate Classification:Vertebrate Classification:
1. Taxonomy - categorizing organisms into groups (taxa) 1. Taxonomy - categorizing organisms into groups (taxa)
1. Organisms are grouped together based on similarities and differences amongst their:
a. Physical traits - structure (anatomy) and function (physiology)
b. Biochemical composition - DNA (genes) and proteins
2. The taxa (groups) used to categorize organisms from general characteristics to more specific are:
KingdomKingdomPhylumPhylum
ClassClassOrderOrder
FamilyFamilyGenusGenus
SpeciesSpecies3. An organism’s scientific name includes its Genus and Species names.
This illustration shows the classification of the grizzly bear from kingdom to species.
Note: as the groups go from more general to more specific, the number of organisms in each group decreases. Figure 15-5, Miller-Levine, Biology
2. Kingdom and 3. Phylum2. Kingdom and 3. Phylum
Vertebrates belong to Kingdom Animalia: multicellular, eukaryotic (cells with organelles), consumers.
Vertebrates belong to Phylum Chordata: have nerve chord.
There are 5 groups of Vertebrates we will study, including Mammalia (shown here)
Taxonomy and the Evolution of Vertebrates
This phylogenetic tree shows one hypothesis of the evolutionary relationships among vertebrates & approximately when important traits appeared.
Each organism’s taxonomic classification reflects these relationships.
Note important evolutionary advancemnets (circled).
Figure 36-2, Miller-Levine, Biology
Part B: Comparing Form & Function Among Vertebrate Classes
Part B: Comparing Form & Function Among Vertebrate Classes
Amphibians
BirdsReptilesFish
Mammals
1. Body Temperature Control (Metabolism)1. Body Temperature Control (Metabolism)
1. Fish, Amphibians, Reptiles
2. Move less and move slower
Endotherms (“warm”-blooded): Produce heat metabolically
1. Birds, Mammals
2. Move more, move faster3. More need for insulation (feathers, fur)
Ectotherms (“cold” blooded): Get heat from environment
3. Less need for insulation
QuickTime™ and aTIFF (Uncompressed) decompressor
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Important Evolutionary Advancement: Endothermy (in Birds and Mammals): Allowed for survival in a greater variety of environments.
2. Movement (Muscles, Skeleton)2. Movement (Muscles, Skeleton)
Side to side movement. Fish, Amphibians, Reptiles
Up and down movement. Birds, Mammals
Limbs:Stick out sideways. Fish, Amphibians
Point more directly down - hold more weight. Reptiles
Point straight down. Birds, Mammals
Vertebral column:QuickTime™ and a
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Important Evolutionary Advancement: Strong skeleton and 4 limbs (first evolved in Amphibians) allowed for better movement on land.
3. Feeding and Digestion3. Feeding and Digestion
Important Evolutionary Advancement: Jaws (first evolved in Fishes). Allowed for greater food variety and size. Digestive system and other structures adapted to feeding habit of organism. Mammalian skullsMammalian skulls
4. Respiration4. Respiration
Anomaly: High complexity, air sacs
Fish: Gills (in most cases)
Low efficiencyHigh efficiency
Important Evolutionary Advancement: Lungs (first evolved in Fishes, further developed in other vertebrates): Led to movement on to land.
5. Internal Transport (Circulation)5. Internal Transport (Circulation)
Fish and Amphibians
Replies, Birds, Mammals
2 chambers3 chambers 4 heart chambers
Heart
Circulation
Important Evolutionary Advancements: Double-Loop circulation and additional heart chambers allow for more efficient circulation of oxygen-rich blood.
6. Excretion6. Excretion
Some anomalies!
Fish
Amphibs.
Birds
MammalsReptiles
Important Evolutionary Advancements: Urea and uric acid are less toxic to the body and can be held internally on land. Pure ammonia waste requires organisms to stay in water to “flush”.
7. Response (Nervous System)7. Response (Nervous System)
Brains
Important Evolutionary Advancements: Folds and size of cerebrum allows for increased intelligence.
8. Reproduction8. Reproduction
Fish, Amphibian--> Reptiles, Birds --> MammalsExternal fertilization Internal Fertilization
Ovoparous --> Ovoviviparous --> Viviparous(Eggs) (developed eggs with amnion) (amnion, live birth)
Lots of anomalies: some fish give live birth, some mammals have eggs, etc.
Fish, Amphibians Reptiles, Birds Mammals
Male and female organs (penis, vagina)
Important Evolutionary Advancement: Amniotic Eggs (first evolved in Reptiles): Eggs with yolk allowed for permanent movement on to land. Internal fertilization allowed for reproduction on land.
8. Reproduction (Development)8. Reproduction (Development)
Early embryonic
development
(all vertebrates
very similar)
Later embryonic
development
(more complex
organisms gain
complexity)