Download Reading Guide Ch 22-24

CHAPTER 22
DESCENT WITH MODIFICATION: A DARWINIAN VIEW OF LIFE
22.2 The Darwinian Revolution
1. Describe how Darwin’s observations on the voyage of the HMS Beagle led him to
formulate and support his theory of evolution.
2. Explain what evidence convinced Darwin that species change over time.
3. Explain how Linnaeus’s classification scheme fit Darwin’s theory of evolution by
natural selection.
4. Distinguish between artificial selection and natural selection.
5. Explain why natural selection can act only on heritable traits.
22.3 The Evidence for Evolution
6. Describe the experiments that supported Endler’s hypothesis that differences in
color patterns in male guppies are due to selective pressure based on predation.
7. Explain how the fossil record may be used to test our current understanding of
evolutionary patterns.
8. Explain how the existence of homologous and vestigial structures can be
explained by Darwin’s theory of natural selection.
9. Explain the problem with the statement that Darwinism is “just a theory”.
Distinguish between the scientific and colloquial use of the word “theory”.
CHAPTER 23
THE EVOLUTION OF POPULATIONS
23.1 Genetic Variation, the Substrate for Natural Selection
1. Explain the statement “It is the population, not the individual, that evolves.”
2. Explain how Mendel’s particulate hypothesis of inheritance provided necessary
support for Darwin’s theory of evolution by natural selection.
3. Define a cline.
4. Explain why the majority of point mutations are harmless.
5. Explain how sexual recombination generates genetic variability.
23.2 The Hardy-Weinberg Principle
6. Explain why meiosis and random fertilization alone will not alter the frequency of
alleles or genotypes in a population.
7. List the five conditions that must be met for a population to remain in HardyWeinberg equilibrium.
8. Write the Hardy-Weinberg equation. Use the equation to calculate allele frequencies
when the frequency of homozygous recessive individuals in a population is 25%.
23.3 Natural Selection, Genetic Drift, and Gene Flow
9. Explain the following statement: “Only natural selection leads to the adaptation of
organisms to their environment.”
10. Distinguish between the bottleneck effect and the founder effect.
Learning Objectives for Campbell/Reece Biology, 8th Edition, © Pearson Education, Inc.
1 of 2
11. Describe how gene flow can act to reduce genetic differences between adjacent
populations.
23.4 Natural Selection and Relative Fitness
12. Define relative fitness.
13. Distinguish between intrasexual selection and intersexual selection.
14. Explain how female preferences for showy male traits may benefit the female.
15. Explain how diploidy can protect a rare recessive allele from elimination by natural
selection.
16. Define neutral variations. Explain why natural selection does not act on these alleles.
17. List four reasons why natural selection cannot produce perfect organisms.
CHAPTER 24
THE ORIGIN OF SPECIES
24.1 What Is a Species?
1. Define Ernst Mayr’s biological species concept.
2. Describe five prezygotic reproductive barriers and give an example of each.
3. Explain a possible cause for hybrid breakdown.
4. Explain how hybrid breakdown maintains separate species even if fertilization occurs.
5. Define and distinguish among the following: ecological species concept, phylogenetic
species concept, and morphological species concept.
24.2 Modes of Speciation
6. Define allopatric speciation. Describe the mechanisms that may lead to genetic
divergence of isolated gene pools.
7. Explain how reproductive barriers evolve. Describe an example of the evolution of a
prezygotic barrier and the evolution of a postzygotic barrier.
8. Define sympatric speciation and explain how polyploidy can cause reproductive
isolation.
9. Explain how habitat differentiation has led to sympatric speciation in North American
maggot flies.
10. Explain how sexual selection has led to sympatric adaptive radiation in the cichlids of
Lake Victoria. Explain how the process of speciation may be reversing, due to pollution
in this lake.
24.3 Hybrid Zones
11. Describe examples that illustrate rapid and gradual speciation events.
12. Explain how a small number of genetic changes may lead to speciation in plants and
animals.
Learning Objectives for Campbell/Reece Biology, 8th Edition, © Pearson Education, Inc.
2 of 2