1. HOW DOES EVOLUTION BY NATURAL SELECTION WORK? Can you see me? If not, Blame Darwin

2. DAY 2 Topic 17 – Theory of Evolution

3. 1. Read quietly instructions to complete Adaptations of Galapagos Tortoises worksheet 2. Choose the best answer for each question. 3. Be prepared to share your answers. DO NOW

4. Modeling Natural Selection THEORY OF EVOLUTION

5. WHAT ARE WE LEARNING TODAY? Benchmarks SC.912.L.15.13 – Describe the conditions required for natural selection, including: overproduction of offspring, inherited variation, and the struggle to survive, which result in differential reproductive success. Learning Objectives I will analyze the reasoning in Darwin’s theory of evolution by natural selection. I will relate the concepts of adaptation and differential reproductive success to the theory of natural selection.

6. “It is not the strongest of the species that survives, nor the most intelligent that survives. It is the one that is most adaptable to change.” Charles Darwin How might natural selection change the frequency of traits in a population in only a few generations? WHAT IS THE ESSENTIAL QUESTION?

7. EVOLUTION OF MEDIUM GROUND FINCHES  There are 13 types of Galapagos finches  They share the same characteristics except for one: all 13 have different beaks.  Their beaks are adapted to the food they eat.  One particular species, the medium ground finches, typically feed on small, soft fruit and seeds because they are easier to crack.  However, during periods of drought, food becomes scarce and the birds are forced to eat more hard seeds that are difficult to break open.  Scientists Peter and Rosemary Grant and their team studied the island’s population of medium ground finches and discovered that there are significant variations in the beak depths of individual birds.  Birds with deeper beaks are better able to crack open hard seeds than birds with shallower beaks. These variations in beak depth made it possible for some of the medium ground finches to get enough food to survive and reproduce during long droughts.

8. CONFERENCE ON EVOLUTION OF FINCHES

9. LAB – MODELING NATURAL SELECTION  Problem Statement:  Problem Statement: Can natural selection change the frequency of traits in a population in only a few generations?  Vocabulary:  Vocabulary: natural selection, adaptation, survival of fittest, differential reproductive success,, struggle for existence  Safety: Take care that you do not injure yourselves or others while moving around or using your utensil “beak”. Consume no food items being used in the activity.

10. LAB – MODELING NATURAL SELECTION Simulation Rules: 1. You may use your hands to hold the plastic utensil (your “beak”) and open the plastic bag (the “nest”). 2. You must respect other “birds,” the other “birds’ beaks,” and the food in the other “birds’ beaks and nests.” 3. You must put your nest in the same general area as the other birds’ nests. 4. When I say that time is up, stop where you are. If you have food held securely in your beak, you may bring it to your nest. 5. Consume none of the food.

11. Data Table 1 Round 1Round 2Round 3 Beak variation Pop. Size % Frequency Pop. Size % Frequency Pop. Size % Frequency Fork (Full) Fork (Inside) Fork (Outside) Total Data Table 2 Beak Variation % Frequency in Round 3 (A) % Frequency in Round 1 (B) Change in % Frequency (A – B) Fork (Full) Fork (Inside) Fork (Outside)

12. Data Table 3 Round 4Round 5Round 6 Beak variation Pop. Size % Frequency Pop. Size % Frequency Pop. Size % Frequency Fork (Full) Fork (Inside) Fork (Outside) Total Data Table 4 Beak Variation % Frequency in Round 6 (A) % Frequency in Round 4 (B) Change in % Frequency (A – B) Fork (Full) Fork (Inside) Fork (Outside)

14. ANALYZE AND DISCUSS 1. Was there one beak phenotype that was more successful than another in round 1-3? If so, which one? 2. Was there one beak phenotype that was more successful than another in round 4-6? If so, which one? 3. Did the frequency of the different beak variations change when the food supply changed? Relate this to what you learned about the finches on Daphne Major. 4. How do you think the results of the Grants’ research might have been different if the beak-depth variations were not passed on from generation to generation, OR inherited? 5. Can natural selection change the frequency of traits in a population in only a few generations? Explain.

15. “It is not the strongest of the species that survives, nor the most intelligent that survives. It is the one that is most adaptable to change.” Charles Darwin How might natural selection change the frequency of traits in a population in only a few generations? WHAT IS THE ESSENTIAL QUESTION?