1. Chapter 24 The Origin of Species

2. Microevolution (you will remember from chapter 23) is the generation- to-generation change in allele frequencies within a species Chapter 24 The Origin of Species

3. Microevolution (you will remember from chapter 23) is the generation- to-generation change in allele frequencies within a species. Macroevolution (on the other hand) is the origin of new species. Chapter 24 The Origin of Species

4. Macroevolution happens two ways: Chapter 24 The Origin of Species

5. Macroevolution happens two ways: Anagenesis – linear evolution Cladagenesis – branching evolution Chapter 24 The Origin of Species

6. Macroevolution happens two ways: Anagenesis – linear evolution Cladagenesis – branching evolution Chapter 24 The Origin of Species

7. What is a species? Chapter 24 The Origin of Species

8. What is a species? Reproductive isolation based on prezygotic and postzygotic barriers. Chapter 24 The Origin of Species

9. Prezygotic barriers: Chapter 24 The Origin of Species

10. Prezygotic barriers: Habitats Mating behaviors Mating seasons Mechanical incompatibility Gamete incompatibility Chapter 24 The Origin of Species

11. Postzygotic barriers: Chapter 24 The Origin of Species

12. Postzygotic barriers: Embryo is inviable Offspring do not survive to adulthood Offspring are infertile Chapter 24 The Origin of Species

13. Species concept does not apply to: Chapter 24 The Origin of Species

14. Species concept does not apply to: Fossils Asexual reproduction Chapter 24 The Origin of Species

15. Other proposed definitions of species: Chapter 24 The Origin of Species

16. Other proposed definitions of species: Ecological Morphological Pluralistic Genealogical Chapter 24 The Origin of Species

17. Speciation Allopatric – Sympatric – Chapter 24 The Origin of Species

18. Speciation Allopatric – Geographic barriers divide a population Sympatric – new species develop in the midst of parent species Chapter 24 The Origin of Species

19. Causes of sympatric speciation: Chapter 24 The Origin of Species

20. Causes of sympatric speciation: Polypoidy (mostly in plants) Host switching (in parasites) Nonrandom mating (in polymorphic populations) Chapter 24 The Origin of Species

21. Punctuated equilibrium Chapter 24 The Origin of Species

22. Punctuated equilibrium Species change quickly as they bud off from parent species, then change relatively little for the rest of their existence. Chapter 24 The Origin of Species

23. Evolutionary Novelties Chapter 24 The Origin of Species

24. Evolutionary Novelties Modifications of older structures Functions may change or may stay the same Chapter 24 The Origin of Species

25. “Evo-Devo” Chapter 24 The Origin of Species

26. “Evo-Devo” Genes that control development play a major role in evolution. Chapter 24 The Origin of Species

27. “Evo-Devo” Chapter 24 The Origin of Species

28. “Evo-Devo” Chapter 24 The Origin of Species

29. “Evo-Devo” Chapter 24 The Origin of Species

30. A trend is not a goal. Evolution is not goal-oriented. Chapter 24 The Origin of Species