TEST BANK
How Humans Evolved
ROBERT BOYD, JOAN B. SILK
Seventh Edition
, Test Bank for How Humans Evolved 7e
by Robert Boyd, Joan Silk
CHAPTER 1: Adaptation by Natural Selection
MULTIPLE CHOICE
1. Adaptations are defined as the components of an organism that
a. allow it to survive and reproduce. c. occur by random chance alone.
b. allow it to evolve more rapidly. d. absolutely never change.
ANS: A DIF: Medium REF: Explaining Adaptation Before Darwin
OBJ: Describe why our modern understanding of the diversity of life is based on the
ideas of Charles Darwin. MSC: Remembering
2. Which of the following is an adaptation?
a. The human eye.
b. Design by a divine creator.
c. Both the human and the fish eye, but humans are better adapted to their
environments than fish are to theirs.
d. The Grand Canyon.
ANS: A DIF: Easy REF: Explaining Adaptation Before Darwin
OBJ: Explain how natural selection can produce very complex adaptations like the
human eye. MSC: Applying
3. Influential nineteenth-century scientists like Charles Darwin concluded that the complex
adaptations we see in plants and animals are problematic and require a special
explanation because
a. a divine creator designed them.
b. it is very unlikely that they arose by random chance alone.
c. they occur in most plants and animals.
d. they have no real function.
ANS: B DIF: Easy REF: Explaining Adaptation Before Darwin
OBJ: Describe why our modern understanding of the diversity of life is based on the
ideas of Charles Darwin. MSC: Understanding
4. Before Charles Darwin proposed his theory of natural selection by adaptation, many
scholars argued that adaptations are proof that
a. evolution is a process based on random chance alone.
b. because of their ability to adapt quickly, humans are better than all other species.
c. God exists and designs all things to fit a specific purpose.
d. there is no way that God can exist.
ANS: C DIF: Easy REF: Explaining Adaptation Before Darwin
OBJ: Describe why our modern understanding of the diversity of life is based on the
ideas of Charles Darwin. MSC: Remembering
5. Charles Darwin is known for his revolutionary argument that
a. plants and animals are not designed by God and do not change over time.
b. plants and animals change slowly over time.
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, c. fossil plants and animals changed, but existing plants and animals do not.
d. plants and animals are created by chance and then evolve through divine intervention.
ANS: B DIF: Easy REF: Darwin’s Theory of Adaptation
OBJ: Describe why our modern understanding of the diversity of life is based on the
ideas of Charles Darwin. MSC: Remembering
6. The postulates that make up Darwin’s theory of adaptation include all of the following
EXCEPT
a. any given environment can support only a certain number of individuals.
b. variation affects the ability of individuals to survive and reproduce.
c. individuals always compete with each other physically.
d. variation is passed from parents to offspring.
ANS: C DIF: Easy REF: Darwin’s Theory of Adaptation
OBJ: Describe why our modern understanding of the diversity of life is based on the
ideas of Charles Darwin. MSC: Remembering
7. For natural selection to occur, variation must exist. This is true because without variation
a. there is no way for change to occur between generations.
b. the one trait that exists is always advantageous, and change is not necessary.
c. there is no competition among individuals.
d. traits are never inherited by offspring.
ANS: A DIF: Hard REF: Darwin’s Theory of Adaptation
OBJ: Explain how competition, variation, and heritability lead to evolution by natural
selection. MSC: Understanding
8. Even though natural selection was named after the artificial selection that plant and
animal breeders use, it really refers to
a. the survival of the physically fit.
b. the reproduction of traits from generation to generation.
c. the selective retention of variation in a population.
d. the variable ability of species to survive and reproduce.
ANS: C DIF: Hard REF: Darwin’s Theory of Adaptation
OBJ: Explain how competition, variation, and heritability lead to evolution by natural
selection. MSC: Understanding
9. During 1976 on the Galápagos Island of Daphne Major, Peter and Rosemary Grant found
evidence of natural selection by adaptation when they observed that
a. finches with shallow beaks were less likely to survive and reproduce than
finches with deep beaks.
b. finch beak size had no effect on survival rates.
c. many more small seeds were available for the finches to eat.
d. more finches with deep beaks died than finches with shallow beaks.
ANS: A DIF: Medium REF: Darwin’s Theory of Adaptation
OBJ: See why natural selection sometimes causes species to become better
adapted to their environments. MSC: Applying
10. Natural selection acted on the medium ground finch on Daphne Major because
a. birds with medium beak sizes experienced higher mortality.
b. a drought changed the environment where the finches lived.
c. offspring of finches with small beaks did not survive the juvenile period.
d. the population reached equilibrium.
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, ANS: B DIF: Medium REF: Darwin’s Theory of Adaptation
OBJ: See why natural selection sometimes causes species to become better
adapted to their environments. MSC: Applying
11. Which of the following is an example of directional selection?
a. Both small and large individuals survive.
b. Only large individuals survive.
c. The proportion of small and large individuals remains the same.
d. Neither small nor large individuals survive.
ANS: B DIF: Easy REF: Darwin’s Theory of Adaptation
OBJ: Understand why natural selection can produce change or cause species to remain
the same over time. MSC: Applying
12. Which of the following is an example of stabilizing selection?
a. Both small and large individuals survive, but medium individuals die off.
b. Only large individuals survive.
c. The proportion of small and large individuals remains the same.
d. Neither small nor large individuals survive.
ANS: D DIF: Easy REF: Darwin’s Theory of Adaptation
OBJ: Understand why natural selection can produce change or cause species to remain
the same over time. MSC: Applying
13. When the Daphne Major finches reach a point where the costs of a having beak larger
than average size outweigh the benefits, beak size will begin to stay the same, and the
population will achieve a(n)
state.
a. direction c. equilibrium
b. trend d. drift
ANS: C DIF: Easy REF: Darwin’s Theory of Adaptation
OBJ: Understand why natural selection can produce change or cause species to remain
the same over time. MSC: Remembering
14. If a population is in stasis (an unchanging state), then
a. the population is in its natural state.
b. natural selection is not acting on the population.
c. the most common type of individual is consistently favored by stabilizing selection.
d. the most common type of individual is consistently favored by disruptive selection.
ANS: C DIF: Medium REF: Darwin’s Theory of Adaptation
OBJ: Understand why natural selection can produce change or cause species to remain
the same over time. MSC: Understanding
15. After a drought, a scientist collects dead birds and finds that most of the individuals
that did not survive to adulthood have either small or large beaks. Given this
pattern, how would you expect selection to act on the population?
a. Selection will not change the mean beak size.
b. Selection will make the mean beak size in the population smaller.
c. Selection will make the mean beak size in the population larger.
d. The entire population will die out.
ANS: A DIF: Medium REF: Darwin’s Theory of Adaptation
OBJ: Understand why natural selection can produce change or cause species to remain
the same over time. MSC: Analyzing
3|Page
How Humans Evolved
ROBERT BOYD, JOAN B. SILK
Seventh Edition
, Test Bank for How Humans Evolved 7e
by Robert Boyd, Joan Silk
CHAPTER 1: Adaptation by Natural Selection
MULTIPLE CHOICE
1. Adaptations are defined as the components of an organism that
a. allow it to survive and reproduce. c. occur by random chance alone.
b. allow it to evolve more rapidly. d. absolutely never change.
ANS: A DIF: Medium REF: Explaining Adaptation Before Darwin
OBJ: Describe why our modern understanding of the diversity of life is based on the
ideas of Charles Darwin. MSC: Remembering
2. Which of the following is an adaptation?
a. The human eye.
b. Design by a divine creator.
c. Both the human and the fish eye, but humans are better adapted to their
environments than fish are to theirs.
d. The Grand Canyon.
ANS: A DIF: Easy REF: Explaining Adaptation Before Darwin
OBJ: Explain how natural selection can produce very complex adaptations like the
human eye. MSC: Applying
3. Influential nineteenth-century scientists like Charles Darwin concluded that the complex
adaptations we see in plants and animals are problematic and require a special
explanation because
a. a divine creator designed them.
b. it is very unlikely that they arose by random chance alone.
c. they occur in most plants and animals.
d. they have no real function.
ANS: B DIF: Easy REF: Explaining Adaptation Before Darwin
OBJ: Describe why our modern understanding of the diversity of life is based on the
ideas of Charles Darwin. MSC: Understanding
4. Before Charles Darwin proposed his theory of natural selection by adaptation, many
scholars argued that adaptations are proof that
a. evolution is a process based on random chance alone.
b. because of their ability to adapt quickly, humans are better than all other species.
c. God exists and designs all things to fit a specific purpose.
d. there is no way that God can exist.
ANS: C DIF: Easy REF: Explaining Adaptation Before Darwin
OBJ: Describe why our modern understanding of the diversity of life is based on the
ideas of Charles Darwin. MSC: Remembering
5. Charles Darwin is known for his revolutionary argument that
a. plants and animals are not designed by God and do not change over time.
b. plants and animals change slowly over time.
1|Page
, c. fossil plants and animals changed, but existing plants and animals do not.
d. plants and animals are created by chance and then evolve through divine intervention.
ANS: B DIF: Easy REF: Darwin’s Theory of Adaptation
OBJ: Describe why our modern understanding of the diversity of life is based on the
ideas of Charles Darwin. MSC: Remembering
6. The postulates that make up Darwin’s theory of adaptation include all of the following
EXCEPT
a. any given environment can support only a certain number of individuals.
b. variation affects the ability of individuals to survive and reproduce.
c. individuals always compete with each other physically.
d. variation is passed from parents to offspring.
ANS: C DIF: Easy REF: Darwin’s Theory of Adaptation
OBJ: Describe why our modern understanding of the diversity of life is based on the
ideas of Charles Darwin. MSC: Remembering
7. For natural selection to occur, variation must exist. This is true because without variation
a. there is no way for change to occur between generations.
b. the one trait that exists is always advantageous, and change is not necessary.
c. there is no competition among individuals.
d. traits are never inherited by offspring.
ANS: A DIF: Hard REF: Darwin’s Theory of Adaptation
OBJ: Explain how competition, variation, and heritability lead to evolution by natural
selection. MSC: Understanding
8. Even though natural selection was named after the artificial selection that plant and
animal breeders use, it really refers to
a. the survival of the physically fit.
b. the reproduction of traits from generation to generation.
c. the selective retention of variation in a population.
d. the variable ability of species to survive and reproduce.
ANS: C DIF: Hard REF: Darwin’s Theory of Adaptation
OBJ: Explain how competition, variation, and heritability lead to evolution by natural
selection. MSC: Understanding
9. During 1976 on the Galápagos Island of Daphne Major, Peter and Rosemary Grant found
evidence of natural selection by adaptation when they observed that
a. finches with shallow beaks were less likely to survive and reproduce than
finches with deep beaks.
b. finch beak size had no effect on survival rates.
c. many more small seeds were available for the finches to eat.
d. more finches with deep beaks died than finches with shallow beaks.
ANS: A DIF: Medium REF: Darwin’s Theory of Adaptation
OBJ: See why natural selection sometimes causes species to become better
adapted to their environments. MSC: Applying
10. Natural selection acted on the medium ground finch on Daphne Major because
a. birds with medium beak sizes experienced higher mortality.
b. a drought changed the environment where the finches lived.
c. offspring of finches with small beaks did not survive the juvenile period.
d. the population reached equilibrium.
2|Page
, ANS: B DIF: Medium REF: Darwin’s Theory of Adaptation
OBJ: See why natural selection sometimes causes species to become better
adapted to their environments. MSC: Applying
11. Which of the following is an example of directional selection?
a. Both small and large individuals survive.
b. Only large individuals survive.
c. The proportion of small and large individuals remains the same.
d. Neither small nor large individuals survive.
ANS: B DIF: Easy REF: Darwin’s Theory of Adaptation
OBJ: Understand why natural selection can produce change or cause species to remain
the same over time. MSC: Applying
12. Which of the following is an example of stabilizing selection?
a. Both small and large individuals survive, but medium individuals die off.
b. Only large individuals survive.
c. The proportion of small and large individuals remains the same.
d. Neither small nor large individuals survive.
ANS: D DIF: Easy REF: Darwin’s Theory of Adaptation
OBJ: Understand why natural selection can produce change or cause species to remain
the same over time. MSC: Applying
13. When the Daphne Major finches reach a point where the costs of a having beak larger
than average size outweigh the benefits, beak size will begin to stay the same, and the
population will achieve a(n)
state.
a. direction c. equilibrium
b. trend d. drift
ANS: C DIF: Easy REF: Darwin’s Theory of Adaptation
OBJ: Understand why natural selection can produce change or cause species to remain
the same over time. MSC: Remembering
14. If a population is in stasis (an unchanging state), then
a. the population is in its natural state.
b. natural selection is not acting on the population.
c. the most common type of individual is consistently favored by stabilizing selection.
d. the most common type of individual is consistently favored by disruptive selection.
ANS: C DIF: Medium REF: Darwin’s Theory of Adaptation
OBJ: Understand why natural selection can produce change or cause species to remain
the same over time. MSC: Understanding
15. After a drought, a scientist collects dead birds and finds that most of the individuals
that did not survive to adulthood have either small or large beaks. Given this
pattern, how would you expect selection to act on the population?
a. Selection will not change the mean beak size.
b. Selection will make the mean beak size in the population smaller.
c. Selection will make the mean beak size in the population larger.
d. The entire population will die out.
ANS: A DIF: Medium REF: Darwin’s Theory of Adaptation
OBJ: Understand why natural selection can produce change or cause species to remain
the same over time. MSC: Analyzing
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