1. Evidence for Evolution
Chapter 21

2. Darwin’s Finches and Natrual Selection
What are the 3 Requirements for Natural Selection to take place?

3. Industrial Melanism and Peppered Moths
Selection by Predation? New Research
Kettlewell

4. Artificial Selection Fruit Flies Crops
Domesticated Animals ….Pleiotropy???

5. Fossil Evidence of Evolution
Age of Fossils can be determined
Fossils document evolutionary transition

6. Evolution of Horses
Changes in Size
Toe Reduction
Tooth size and Shape

7. Anatomical Evidence For Evolution
Homologous Structures…So what are analogous structures?
Vestigial Structures
Early Embryonic Development

8. Convergent Evolution

9. Darwin’s Critics 1. Evolution is not Solidly Demonstrated
2. The intelligent design argument
3. Evolution violates the 2nd law of thermodynamics
4.Proteins are too improbable
5.Natural Selection does not imply evolution
6. There are no fossil intermediates
7. The irreducible complexity argument

10. The Origin of Species
Chapter 22

11. The Nature of Species
Sympatric Species
Subspecies

12. The Biological Species Concept
“ A species is a group of actually or potentially interbreeding natural population which is reproductively isolated from other such groups”
Does not explain all observations

13. Reproductive Isolation
Geographic Isolation
Ecological Isolation
Behavioral Isolation
Temporal Isolation
Mechanical Isolation
Prevention of Gamete Fusion
Hybrid Inviability or Infertility

14. Evolution of Reproductive Isolation
Selection May reinforce Isolating Mechanisms
Gene Flow Counters Speciation
Reinforcement - initially incomplete isolating mechanisms are reinforced by natural selection until they are completely effective

15. Speciation Genetic Drift Natural Selection Adaptation Allopatric
Sympatric
Polypoidy

16. Adaptive Radiation
Hawaiian Drosophila
Darwins Finches
Chichlids

17. Pace of Evolution
Gradualism vs Punctuated Equilibrium

18. Extinction Through Time
5 Mass Extinctions have Occurred in the Past
Permian, 250 mya
Cretaceous, 65 mya
6th extinction underway

19. Future of Evolution
Thoughts????