1. I. I.Evolution A. A.Descent with Modification B. B.Natural Selection Provides mechanism for better-adapted organisms to pass traits to next generation (doesn’t create adaptations) Darwin: Cumulative changes in population over sufficiently long periods of time could produce new species from ancestral ones Descent with Modification accounts for unity of life (common ancestor) Natural Selection over time accounts for diversity of life Fig. 1.19

2. Fig. 1.22

3. II. II.Scientific Method A. A.Process 1. 1.Observation Careful; Include as many parameters as possible Observations  Induction  Hypothesis 2. 2.Question 3. 3.Hypothesis Possible cause Reflect past experience (educated guess) Multiple (consider alternative explanations) Testable Falsifiable 4. 4.Prediction Hypothesis/Principle  Deduction  Prediction 5. 5.Experiment Experimental group, Control group, Replication 6. 6.Results/Interpretation 7. 7.Scientific Theory

4. Fig. 1.24

6. Fig. 1.25

7. Fig. 1.26

8. Fig. 1.27

9. II. II.Scientific Method B. B.Field Observations vs. Controlled Experiments 1. 1.Field Observations (in situ) Natural setting Uncontrolled variables Examples? 2. 2.Controlled Experiment (usually ex situ) Fewer uncontrolled variables Test one or a few variable(s) at a time Artificial setting (especially ex situ)