Mechanisms of Change – Naturally It is not the strongest or the most intelligent who will survive but those who can best manage change.” ― Charles Darwin Section 1 – Vocabulary Below is a list of all of the biology vocabulary terms used in the Unit. By the end of the Unit, you will be able to write a working definition of each term and correctly adaptive radiation allele gene equilibrium gene flow natural selection population structure artificial selection biogeography gene pool genetic drift genetic variation punctuated equilibrium reproductive isolation selective mating bottleneck effect isolation speciation gradualism immigration mutation species stabilizing selection survival of the fittest analogous directional selection disruptive selection emigration geographic Section 2 – Mastery Objectives / Critical Thinking Skills 1. Define gene pool and give an example 2. Define five processes that alter the gene pool 3. Define genetic variation and describe how it changes in small and large populations over time 4. Define natural selection and describe three types of natural selection 5. List 2 key mechanisms that drive natural selection 6. Define speciation 7. Distinguish between the concepts of gradualism and punctuated equilibrium. 8. Explain why sex is important in evolution. Section 3A –Suggested Readings Miller and Levine – pp 397 -402; 404-410 Section 3B –Relevant Websites Refer to the class wiki (http://nnhsbiology.pbworks.com) Section 4 –– Outside Class Assignments Thoughtfully answer each of the following questions or comments. Include all your reasoning and show all your work wherever it is appropriate. To receive any credit for a question, your answer must be a correctly numbered restatement of the question or statement followed by a series of complete sentences. No phrases, partial answers or isolated numbers will be given credit! Late work will be discounted 15%. 1. Create a concept map for each of the following groups of terms a. Gene pool. Gene frequency, small gene pool, genetic drift, large gene pool, emigration, immigration, population b. Natural selection, directional selection, stabilizing selection, disruptive selection, speciation, artificial selection c. Gene flow, geographical isolation, reproductive isolation, bottleneck effect d. Speciation, isolation, punctuated equilibrium, gradualism, survival of the fittest 2. What is the theory of natural selection? Give an example of natural selection at work in your backyard. What species is being affected? How is it being affected? What genes are being selected for or against? How will the gene pool be different in 10 years if the selection continues without other changes being introduced? Will the other alleles of that gene disappear from the population? (Hint: Remember the naked bunnies!) 3. We studied the story of the Peppered Moths in England. a. Did peppered moths in England ever evolve into two species? b. Explain how you came to your answer for a. c. What factors are involved for species to arise from a common ancestor? d. How do you know when speciation has happened? 4. Explain the difference between gradualism and punctuated equilibrium in evolution. Give an example of each and explain how it demonstrates the concept. 5. In the evolution of life on earth some big “inventions” have changed the direction of life forms. a. What forces may have selected for multi-cellular organisms? b. What was the advantage to having eyes? c. How did photosynthesis come to dominate the landscape? How did it change the earth? d. Is there a role for death in evolution? e. What is the role of sex in evolution? f. Does altruism have a role in evolution? How would it be beneficial? 6. Identify two major factors that contributed to Darwin’s finches undergoing speciation and then describe how these factors drove speciation. 7. Some folks believe that humans have stopped evolving and claim that humans are in a post evolution phase. a. Do you agree or disagree with this idea? b. What evidence can you offer to support your opinion? 8. Some folks think that humans with certain “expensive” diseases i.e. “bad” genes should not be allowed to procreate. a. What would you define as an “expensive” or “bad” gene? b. Should people with these genes be allowed to procreate? c. Do people with “bad” genes weaken the gene pool?