* * speciation & patterns of evolution. * explain how the isolation (physical or genetic) of...
TRANSCRIPT
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•Explain how the isolation (physical or genetic) of populations can lead to speciation.
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Objectives
Vocabualry
•Species•Speciation•Geographic isolation•Allopatric Speciation•Reproductive Isolation
•Sympatric Speciation•Gradualism•Punctuated equilibrium•Adaptive Radiation/Divergent Evolution•Convergent Evolution
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•Species: a group of organisms that look alike and can interbreed to produce fertile offspring in nature.
•SPECIATION: when members of Similar populations can no longer interbreed to produce fertile offspring.
What is speciation?
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What can cause speciation?
1. GEOGRAPHIC ISOLATION•Physical barrier separates a population
•Allopatric Speciation: New species arise as a result of geographic isolation
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What can cause speciation?2. REPRODUCTIVE ISOLATION•Organisms can no longer mate to produce offspring•Timing•Behavior•Habitat•Infertile Hybrid offspring
•Sympatric Speciation•New species arise as a result of reproductive isolation
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•Gradualism•species originate through a gradual change of adaptations
•Punctuated equilibrium•speciation occurs relatively quickly, in rapid bursts, with long periods of genetic equilibrium in between.
How fast does speciation occur?
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How does environment affect speciation?
•Divergent evolution/Adaptive Radiation:•when populations change as they adapt to different environmental conditions, eventually resulting in new species.
•Convergent evolution:•distantly related organisms evolve similar traits•occurs when unrelated species occupy similar environments in different parts of the world
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Natural processes such as speciation and gradualism provide the genetic basis for _____.
A.evolutionB.biogenesisC.spontaneous generationD.sexual reproduction
Question #1
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Natural processes such as speciation and gradualism provide the genetic basis for _____.
A.evolutionB.biogenesisC. spontaneous generationD.sexual reproduction
Question #1
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A pattern of evolution that results when two unrelated species begin to appear similar because of environmental conditions is _____.
A.disruptive selectionB.directional selectionC.convergent evolutionD.divergent evolution
Question #2