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Take Out The Following Labs

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  1. Take Out The Following Labs SPECIATION MICROEVOLUTION & ALLELE FREQUENCY

  2. “When The Student Is Ready, The Master Appears”-Buddhist Proverb

  3. Cladistics Has Shown That Insects Have Evolved Through CONVERGENT evolution SIX DIFFERENT TIMES!

  4. Evolution of Insects • 75% of all animals on earth are insects • Insects were NOT the first animals • Evolved during the Devonian (~400 mya) • The path of insect evolution is very different from all other animals

  5. Gradualism Slow, incremental changes in allele frequency and phenotype over time Punctuated Equilibrium Long periods of no change in allele frequency and/or phenotype interrupted by rapid “bursts” of drastic change Different Models For Rate of Evolutionary Change

  6. Divergent Adaptive Radiation Due to selective pressures, variations are favored and ancestral species become physically and reproductively isolated Convergent Organisms of different ancestry are acted upon by selective pressures that favor similar variations Divergent v. Convergent Evolution

  7. How are these concepts addressed in the evolution of Geospiza?

  8. Mainland Sympatric: Changes In Habitat/Food Source

  9. Windsor Sympatric No Founder’s Effect

  10. Norcross Allopatric

  11. Warwick Allopatric

  12. Which factors were most influential in the evolution of Birguslatro?

  13. Microevolution Lab Results • Which atoll had highest frequency of black carapaces? • Wotho • Why? Founder’s Effect, Outbreeding or Selective Pressures? • Founder’s effect. No outbreeding or selective pressures • What about frequency of four legs? • Same

  14. Microevolution Lab Results • How do frequencies of carapace color correlate with phenotypic frequencies? • Direct relationship. Highest frequency of black correlates with highest frequency of recessive allele • How do frequencies of appendages correlate with allele frequencies? • More direct due to incomplete dominance

  15. Microevolution Results • Similarities with pollenpeeper analysis? • Reproductive isolation amplifies single phenotypes • Is artificial selection influencing any of the atolls? • Lae, human selection against red • Which atoll was most likely to exhibit Hardy-Weinberg equilibrium? • Wotho, due to no selective pressures or outbreeding

  16. What about convergent evolution?

  17. Convergent Evolution & The Eye

  18. The Kung & Steatopygia

  19. Convergent Evolution

  20. How do scientists evaluate the direction and pattern of evolutionary change?

  21. Cladistics • Clade: from Greek word klados (branch) • Group of closely related organisms with shared derived properties

  22. Cladogram • Diagram showing time and direction of divergence (or, occasionally, convergence)

  23. Defining Cladistics By Phenotypic Traits • Plesiomorphy = Ancestral trait shared by members of a clade • Apomorphy = a newly evolved trait that separates taxa from their clade