1. Causes of Diversity and Evolution of Life on Earth Charles Darwin Alfred Russell Wallace

2. Causes for Diversity of Life 1. All populations have the potential to increase in size 2. Many populations retain a constant size Many individuals die young 3. Individuals in a population differ in their abilities Some of these abilities affect survival 4. Best adapted individuals are most likely to survive and produce offspring (Natural Selection) “Abilities” are passed on to offspring (Genetics) 5. Over time the “abilities” of the population shift to include advantageous traits (Evolution) 1. All populations have the potential to increase in size 2. Many populations retain a constant size Many individuals die young 3. Individuals in a population differ in their abilities Some of these abilities affect survival 4. Best adapted individuals are most likely to survive and produce offspring (Natural Selection) “Abilities” are passed on to offspring (Genetics) 5. Over time the “abilities” of the population shift to include advantageous traits (Evolution)

3. Note: Natural Selection Affects Individuals Evolution Affects Populations

4. Net Result: Populations change with time to become better adapted to their environment (Evolution)

5. Example: Microbe Resistance Apply Antibiotic Survivor’s with Resistance Reproduce

6. Why is there Genetic Variation? (How do will fill the Gene Pool?)

7. How does it Work? Variation is a result of (1) Mutations and (2) Sex Errors occur in DNA Replication On average 1:10,000-100,000 genes per individual per generation Errors increased by exposure to radiation, etc. Most Mutations are bad or at least neutral What is “good” depends on environmental conditions

8. Evidence for Evolution

9. Evidence for Evolution: Fossils

10. Evidence for Evolution: Analogous Structures

11. Evidence for Evolution: Homologous Structures

13. Evidence for Evolution: Embryology

14. Evidence for Evolution: Biochemistry of Life

15. Evidence for Evolution: Gene Sequencing

16. Evidence for Evolution: Artificial Selection

18. Evidence for Evolution: Modern Examples

19. Some Interesting Effects of Evolution

20. Evolution & Psuedoextinction Species A Species B Through time Species A evolves into Species B In effect, Species A goes extinct

21. Extinction Species A Sometimes a species cannot adapt fast enough to environmental change or competition

22. “Background Extinction”: Species Lifespan

23. Mass Extinction

24. Evolution & Speciation Species A Species B Species C Species A is separated into 2 isolated populations, each affected by different environmental conditions In effect, Species A goes Extinct

25. Speciation of Kaibab & Abert Squirrels

26. Speciation of Hawaiian Honeycreepers

27. Diversity Increases

28. Classification: Based on Evolutionary Relationships Species Genus Family

29. Convergent Evolution

30. Coevolution: Plants and Pollinators

31. Coevolution: Predator/Prey

32. Conclusions: Biodiversity, genetic diversity, and community complexity are all the result of 100’s million of years of evolution