Lesson Plans

Biology 5th Edition ©1999

by Campbell, Reece, Mitchell

Week 18: Evolution of Populations and Modes of Speciation

Chapter 22: Descent with Modification: A Darwinian View of Life
Chapter 23: The Evolution of Populations
Chapter 24: The Origin of Species

College Board Performance Objectives:

• Explain the role of natural selection in the process of evolution.
• Explain how heredity and natural selection are involved in the process of evolution.
• Explain the mechanisms that account for speciation and macroevolution.
• Explain the different patterns of evolution that have been identified and what mechanisms are responsible for each of these patterns.

College Board Lab Objectives:

• Explain how natural selection can alter allelic frequencies in a population.
• Explain the Hardy-Weinberg equation and its use in determining the frequency of alleles in a population.
• Explain the effects on the allelic frequencies of selection against the homozygous recessive or other genotypes.
• Calculate the frequencies of alleles and genotypes in the gene pool of a population using the Hardy-Weinberg formula.
• Discuss natural selection and other causes of microevolution as deviations from the conditions required to maintain Hardy-Weinberg equilibrium.

Suggested Laboratory Experiments:

Resources:

• Chapter 22: Descent with Modification: A Darwinian View of Life, pp. 414–427
• Chapter 23: The Evolution of Populations, pp. 428–444
• Chapter 24: The Origin of Species, pp. 445–463
• Instructor's Guide, pp. 339–376
• Student Study Guide, pp. 171–186
• Test Bank, pp. 269–298
• Lab Manual:
• CD-ROM: Chapters 22, 23, and 24 include narrated presentations, activities, and links to the Internet.

Pacing Guide:

• Chapter 22: Descent with Modification: A Darwinian View of Life—1 day
  Review the song Rudolph the Red Nose Reindeer. Analyze the part when Rudolph begins to have his red nose. The questions are: "Did Rudolph have a red nose before the foggy night? Did the foggy night cause his red nose?" Discussion of these questions will help students understand that the adaptation is present before the environmental stress occurs. Then have them apply this logic to:
• Chapter 23: The Evolution of Populations—1 day
  The bottleneck effect on p. 433 is a good exercise to help students visualize the gene pool.
• Chapter 24: The Origin of Species—1 day
  Discussion of the Grand Canyon and Island Speciation are good tools to help students understand speciation.
• Biology AP* Lab 8: Population Genetics and Evolution—2 days
  Lab Topic 11, Population Genetics: The Hardy-Weinberg Theorem is a good supplement to the AP* Lab and Lab Topic 12, Population Genetics: Determining Genetic Variation, is good if there is enough time. If time is limited, then a discussion of it would be helpful.
• Block Scheduling
  The flow of the following can be accomplished in three-fourths of a block each: Descent with Modification: A Darwinian View of Life, The Evolution of Populations, The Origin of Species, and AP* Lab 8: Population Genetics and Evolution.

Key Words:

Suggested Exercises:
Critical thinking questions and end-of-chapter activities are included in these exercises.

1. Challenge Questions, p. 427 #1, p. 444 #1, and p. 463 #1
2. Science, Technology, and Society, p. 427 #1, p. 444 #1, and p. 463 #1
3. Have students think of songs and stories that support Darwin's theory of evolution.
4. Divide the class into groups. Distribute pictures of organisms of the same species in their natural environments. Have students list traits and adaptations that might help each species survive in its environment.

Troubleshooting Tips/Error Traps:

• Emphasize that various traits occur as a result of recombination of DNA, and that some traits help organisms to survive environmental change. The trait is there before the environmental stress. Did antibiotics cause bacteria to become resistant? No, antibiotics did not cause bacteria to become resistant. Some bacteria had resistance to bacteria before the use of antibiotics. When antibiotics were introduced, the weak died and the resistant ones survived. The survivors had more space and food since the others were dead. There was natural selection and survival of the fittest. It is good to relate evolution to students' daily life, and to the quick reproductive cycle of bacteria and insects.
• Lab 8: Population Genetics and Evolution requires a large group. Small classes make the results of the lab difficult to interpret. Use this situation to explain how a large population is needed in order to study population genetics. You could also explain to the class that you could have invited other students in order to increase the population size.