Deck 22: Descent With Modification: a Darwinian View of Life

Question 1

As a young biologist, Charles Darwin had expected the living plants of temperate South America would resemble those of temperate Europe, but he was surprised to find that they more closely resembled the plants of tropical South America. The biological explanation for this observation is most properly associated with the field of

A)meteorology.
B)embryology.
C)vertebrate anatomy.
D)bioengineering.
E)biogeography.

Answer 1

E

Question 2

Darwin's mechanism of natural selection required long time spans in order to modify species. From whom did Darwin get the concept of Earth's ancient age?

A)Georges Cuvier
B)Charles Lyell
C)Alfred Wallace
D)Thomas Malthus
E)John Henslow

Answer 2

B

Question 3

Natural selection is based on all of the following except

A)genetic variation exists within populations.
B)the best-adapted individuals tend to leave the most offspring.
C)individuals who survive longer tend to leave more offspring than those who die young.
D)populations tend to produce more individuals than the environment can support.
E)individuals adapt to their environments and, thereby, evolve.

Answer 3

E

Question 4

The following questions refer to Figure 22.1, which shows an outcrop of sedimentary rock whose strata are labeled A-D.

Figure 22.1
If "x" indicates the location of fossils of two closely related species, then fossils of their most-recent common ancestor are most likely to occur in which stratum?

Question 5

What was the prevailing notion prior to the time of Lyell and Darwin?

A)Earth is a few thousand years old, and populations are unchanging.
B)Earth is a few thousand years old, and populations gradually change.
C)Earth is millions of years old, and populations rapidly change.
D)Earth is millions of years old, and populations are unchanging.
E)Earth is millions of years old, and populations gradually change.

Question 6

Which of these naturalists synthesized a concept of natural selection independently of Darwin?

A)Charles Lyell
B)Gregor Mendel
C)Alfred Wallace
D)John Henslow
E)Thomas Malthus

Question 7

Which pair would have been likely to agree that strata such as those depicted here were deposited gradually over long periods of time by subtle mechanisms that are still at work?

A)Cuvier and Aristotle
B)Cuvier and Lamarck
C)Lyell and Linnaeus
D)Aristotle and Hutton
E)Hutton and Lyell

Question 8

Which of the events described below agrees with the idea of catastrophism?

A)The gradual uplift of the Himalayas by the collision of the Australian crustal plate with the Eurasian crustal plate
B)The formation of the Grand Canyon by the Colorado River over millions of years
C)The gradual deposition of sediments many kilometers thick on the floors of seas and oceans
D)The sudden demise of the dinosaurs, and various other groups, by the impact of a large extraterrestrial body with Earth
E)The development of the Galapagos Islands from underwater seamounts over millions of years

Question 9

During a study session about evolution, one of your fellow students remarks, "The giraffe stretched its neck while reaching for higher leaves; its offspring inherited longer necks as a result." Which statement is most likely to be helpful in correcting this student's misconception?

A)Characteristics acquired during an organism's life are generally not passed on through genes.
B)Spontaneous mutations can result in the appearance of new traits.
C)Only favorable adaptations have survival value.
D)Disuse of an organ may lead to its eventual disappearance.
E)Overproduction of offspring leads to a struggle for survival.

Question 10

Which of these conditions should completely prevent the occurrence of natural selection in a population over time?

A)All variation between individuals is due only to environmental factors.
B)The environment is changing at a relatively slow rate.
C)The population size is large.
D)The population lives in a habitat where there are no competing species present.

Question 11

Which of the following represents an idea that Darwin learned from the writings of Thomas Malthus?

A)All species are fixed in the form in which they are created.
B)Populations tend to increase at a faster rate than their food supply normally allows.
C)Earth changed over the years through a series of catastrophic upheavals.
D)The environment is responsible for natural selection.
E)Earth is more than 10,000 years old.

Question 12

Which statement about natural selection is most correct?

A)Adaptations beneficial in one habitat should generally be beneficial in all other habitats as well.
B)Different species that occupy the same habitat will adapt to that habitat by undergoing the same genetic changes.
C)Adaptations beneficial at one time should generally be beneficial during all other times as well.
D)Well-adapted individuals leave more offspring, and thus contribute more to the next generation's gene pool, than do poorly adapted individuals.
E)Natural selection is the sole means by which populations can evolve.

Question 13

Who would have proposed that the boundaries between each stratum mark the occurrence of different localized floods?

A)Lyell
B)Cuvier
C)Hutton
D)Darwin
E)Lamarck

Question 14

Which group is composed entirely of individuals who maintained that species are fixed (i.e., unchanging)?

A)Aristotle, Cuvier, and Lamarck
B)Linnaeus, Cuvier, and Lamarck
C)Lyell, Linnaeus, and Lamarck
D)Aristotle, Linnaeus, and Cuvier
E)Hutton, Lyell, and Darwin

Question 15

Given a population that contains genetic variation, what is the correct sequence of the following events, under the influence of natural selection?
1) Well-adapted individuals leave more offspring than do poorly adapted individuals.
2) A change occurs in the environment.
3) Genetic frequencies within the population change.
4) Poorly adapted individuals have decreased survivorship.

A)2 → 4 → 1 → 3
B)4 → 2 → 1 → 3
C)4 → 1 → 2 → 3
D)4 → 2 → 3 → 1
E)2 → 4 → 3 → 1

Question 16

Catastrophism, meaning the regular occurrence of geological or meteorological disturbances (catastrophes), was Cuvier's attempt to explain the existence of

A)evolution.
B)the fossil record.
C)uniformitarianism.
D)the origin of new species.
E)natural selection.

Question 17

The following questions refer to Figure 22.1, which shows an outcrop of sedimentary rock whose strata are labeled A-D.

Figure 22.1
Which stratum should contain the greatest proportion of extinct organisms?

Question 18

In the mid-1900s, the Soviet geneticist Lysenko believed that his winter wheat plants, exposed to ever-colder temperatures, would eventually give rise to ever more cold-tolerant winter wheat. Lysenko's attempts in this regard were most in agreement with the ideas of

A)Cuvier.
B)Hutton.
C)Lamarck.
D)Darwin.
E)Plato.

Question 19

Charles Darwin was the first person to propose

A)that evolution occurs.
B)a mechanism for how evolution occurs.
C)that the Earth is older than a few thousand years.
D)a mechanism for evolution that was supported by evidence.
E)a way to use artificial selection as a means of domesticating plants and animals.

Question 20

In Darwin's thinking, the more closely related two different organisms are, the

A)more similar their habitats are.
B)less similar their DNA sequences are.
C)more recently they shared a common ancestor.
D)less likely they are to have the same genes in common.
E)more similar they are in size.

Question 21

The following questions refer to the evolutionary tree in Figure 22.2.
The tree's horizontal axis is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. The labeled branch points on the tree (V-Z) represent various common ancestors. Let's say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species.

Figure 22.2
DDT was once considered a "silver bullet" that would permanently eradicate insect pests. Today, instead, DDT is largely useless against many insects. Which of these would have been required for this pest eradication effort to be successful in the long run?

A)Larger doses of DDT should have been applied.
B)All habitats should have received applications of DDT at about the same time.
C)The frequency of DDT application should have been higher.
D)None of the individual insects should have possessed genomes that made them resistant to DDT.
E)DDT application should have been continual.

Question 22

The following questions refer to the evolutionary tree in Figure 22.2.
The tree's horizontal axis is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. The labeled branch points on the tree (V-Z) represent various common ancestors. Let's say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species.

Figure 22.2
Which of the five common ancestors, labeled V-Z, has been most successful in terms of the percent of its derived species that are extant?

A)V
B)W
C)X
D)Y
E)Z

Question 23

If the HMS Beagle had completely bypassed the Galapagos Islands, Darwin would have had a much poorer understanding of the

A)relative stability of a well-adapted population's numbers over many generations.
B)ability of populations to undergo modification as they adapt to a particular environment.
C)tendency of organisms to produce the exact number of offspring that the environment can support.
D)unlimited resources that support population growth in most natural environments.
E)lack of genetic variation among all members of a population.

Question 24

The following questions refer to the evolutionary tree in Figure 22.2.
The tree's horizontal axis is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. The labeled branch points on the tree (V-Z) represent various common ancestors. Let's say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species.

Figure 22.2
Which of the five common ancestors, labeled V-Z, has given rise to the greatest number of species, both extant and extinct?

A)V
B)W
C)X
D)Y
E)Z

Question 25

Which of the following statements is an inference of natural selection?

A)Subsequent generations of a population should have greater proportions of individuals that possess traits better suited for success in unchanging environments.
B)An individual organism undergoes evolution over the course of its lifetime.
C)Habitats do not generally have unlimited resources.
D)Natural populations tend to reproduce to their full biological potential.
E)Some of the variation that exists among individuals in a population is genetic.

Question 26

A biologist studied a population of squirrels for 15 years. During that time, the population was never fewer than 30 squirrels and never more than 45. Her data showed that over half of the squirrels born did not survive to reproduce, because of competition for food and predation. In a single generation, 90% of the squirrels that were born lived to reproduce, and the population increased to 80. Which inference(s)about this population might be True?

A)The amount of available food may have increased.
B)The number of predators may have decreased.
C)The squirrels of subsequent generations should show greater levels of genetic variation than previous generations, because squirrels that would not have survived in the past will now survive.
D) A and B only
E)A, B, and C

Question 27

The following questions refer to the evolutionary tree in Figure 22.2.
The tree's horizontal axis is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. The labeled branch points on the tree (V-Z) represent various common ancestors. Let's say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species.

Figure 22.2
Which statement best describes the evolution of pesticide resistance in a population of insects?

A)Individual members of the population slowly adapt to the presence of the chemical by striving to meet the new challenge.
B)All insects exposed to the insecticide begin to use a formerly silent gene to make a new enzyme that breaks down the insecticide molecules.
C)Insects observe the behavior of other insects that survive pesticide application, and adjust their own behaviors to copy those of the survivors.
D)Offspring of insects that are genetically resistant to the pesticide become more abundant as the susceptible insects die off.

Question 28

The following questions refer to the evolutionary tree in Figure 22.2.
The tree's horizontal axis is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. The labeled branch points on the tree (V-Z) represent various common ancestors. Let's say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species.

Figure 22.2
According to this tree, what percent of the species seem to be extant (i.e., not extinct)?

A)25%
B)33%
C)50%
D)66%
E)75%

Question 29

Which of Darwin's ideas had the strongest connection to Darwin having read Malthus's essay on human population growth?

A)Descent with modification
B)Variation among individuals in a population
C)Struggle for existence
D)The ability of related species to be conceptualized in "tree thinking"
E)That the ancestors of the Galapagos finches had come from the South American mainland

Question 30

Which of the following must exist in a population before natural selection can act upon that population?

A)Genetic variation among individuals
B)Variation among individuals caused by environmental factors
C)Sexual reproduction
D)B and C only
E)A, B, and C

Question 31

The following questions refer to the evolutionary tree in Figure 22.2.
The tree's horizontal axis is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. The labeled branch points on the tree (V-Z) represent various common ancestors. Let's say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species.

Figure 22.2
Which pair would probably have agreed with the process that is depicted by this tree?

A)Cuvier and Lamarck
B)Lamarck and Wallace
C)Aristotle and Lyell
D)Wallace and Linnaeus
E)Linnaeus and Lamarck

Question 32

The following questions refer to the evolutionary tree in Figure 22.2.
The tree's horizontal axis is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. The labeled branch points on the tree (V-Z) represent various common ancestors. Let's say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species.

Figure 22.2
Evolutionary trees such as this are properly understood by scientists to be

A)theories.
B)hypotheses.
C)laws.
D)dogmas.
E)facts.

Question 33

During drought years on the Galapagos, small, easily eaten seeds become rare, leaving mostly large, hard-cased seeds that only birds with large beaks can eat. If a drought persists for several years, what should one expect to result from natural selection?

A)Small birds gaining larger beaks by exercising their mouth parts.
B)Small birds mutating their beak genes with the result that later-generation offspring have larger beaks.
C)Small birds anticipating the long drought and eating more to gain weight and, consequently, growing larger beaks.
D)
More small-beaked birds dying than larger-beaked birds. The offspring produced in subsequent generations have a higher percentage of birds with large beaks.
E)Larger birds eating less so smaller birds can survive.

Question 34

The following questions refer to the evolutionary tree in Figure 22.2.
The tree's horizontal axis is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. The labeled branch points on the tree (V-Z) represent various common ancestors. Let's say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species.

Figure 22.2
How many separate species, both extant and extinct, are depicted in this tree?

A)2
B)3
C)4
D)5
E)6

Question 35

The following questions refer to the evolutionary tree in Figure 22.2.
The tree's horizontal axis is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. The labeled branch points on the tree (V-Z) represent various common ancestors. Let's say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species.

Figure 22.2
Which of the five common ancestors, labeled V-Z, has been least successful in terms of the percent of its derived species that are extant?

A)V
B)W
C)X
D)Y
E)Z

Question 36

To observe natural selection's effects on a population, which of these must be True?

A)One must observe more than one generation of the population.
B)The population must contain genetic variation.
C)Members of the population must increase or decrease the use of some portion of their anatomy.
D)A and C only
E)A and B only

Question 37

The graph in Figure 22.3 depicts four possible patterns for the abundance of 3TC-resistant HIV within an infected human over time.

Figure 22.3
If 3TC resistance is costly for HIV, then which plot (I-IV)best represents the response of a strain of 3TC-resistant HIV over time, if 3TC administration begins at the time indicated by the arrow?

A)I
B)II
C)III
D)IV

Question 38

The following questions refer to the evolutionary tree in Figure 22.2.
The tree's horizontal axis is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. The labeled branch points on the tree (V-Z) represent various common ancestors. Let's say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species.

Figure 22.2
Some members of a photosynthetic plant species are genetically resistant to an herbicide, while other members of the same species are not resistant to the herbicide. Which combination of events should cause the most effective replacement of the non-herbicide-resistant strain of plants by the resistant strain?
1) The presence of the herbicide in the environment
2) The absence of the herbicide from the environment
3) The maintenance of the proper conditions for one generation
4) The maintenance of the proper conditions for many generations

A)1 and 3
B)1 and 4
C)2 and 3
D)2 and 4

Question 39

Of the following anatomical structures, which is homologous to the wing of a bird?

A)Dorsal fin of a shark
B)Hindlimb of a kangaroo
C)Wing of a butterfly
D)Tail fin of a flying fish
E)Flipper of a cetacean

Question 40

The following questions refer to the evolutionary tree in Figure 22.2.
The tree's horizontal axis is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. The labeled branch points on the tree (V-Z) represent various common ancestors. Let's say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species.

Figure 22.2
In a hypothetical environment, fishes called pike-cichlids are visual predators of algae-eating fish (i.e., they locate their prey by sight). If a population of algae-eaters experiences predation pressure from pike-cichlids, which of the following should least likely be observed in the algae-eater population over the course of many generations?

A)Selection for drab coloration of the algae-eaters
B)Selection for nocturnal algae-eaters (active only at night)
C)Selection for larger female algae-eaters, bearing broods composed of more, and larger, young
D)Selection for algae-eaters that become sexually mature at smaller overall body sizes
E)Selection for algae-eaters that are faster swimmers

Question 41

The upper forelimbs of humans and bats have fairly similar skeletal structures, whereas the corresponding bones in whales have very different shapes and proportions. However, genetic data suggest that all three kinds of organisms diverged from a common ancestor at about the same time. Which of the following is the most likely explanation for these data?

A)Humans and bats evolved by natural selection, and whales evolved by Lamarckian mechanisms.
B)Forelimb evolution was adaptive in people and bats, but not in whales.
C)Natural selection in an aquatic environment resulted in significant changes to whale forelimb anatomy.
D)Genes mutate faster in whales than in humans or bats.
E)Whales are not properly classified as mammals.

Question 42

Structures as different as human arms, bat wings, and dolphin flippers contain many of the same bones, these bones having developed from very similar embryonic tissues. How do biologists interpret these similarities?

A)By identifying the bones as being homologous
B)By the principle of convergent evolution
C)By proposing that humans, bats, and dolphins share a common ancestor
D)A and C only
E)A, B, and C

Question 43

Which of the following pairs of structures is least likely to represent homology?

A)The wings of a bat and the arms of a human
B)The hemoglobin of a baboon and that of a gorilla
C)The mitochondria of a plant and those of an animal
D)The wings of a bird and those of an insect
E)The brain of a cat and that of a dog

Question 44

The theory of evolution is most accurately described as

A)an educated guess about how species originate.
B)one possible explanation, among several scientific alternatives, about how species have come into existence.
C)an opinion that some scientists hold about how living things change over time.
D)an overarching explanation, supported by much evidence, for how populations change over time.
E)an idea about how acquired characteristics are passed on to subsequent generations.

Question 45

Logically, which of these should cast the most doubt on the relationships depicted by an evolutionary tree?

A)None of the organisms depicted by the tree ate the same foods.
B)Some of the organisms depicted by the tree had lived in different habitats.
C)The skeletal remains of the organisms depicted by the tree were incomplete (i.e., some bones were missing).
D)Transitional fossils had not been found.
E)Relationships between DNA sequences among the species did not match relationships between skeletal patterns.

Question 46

Which of the following pieces of evidence most strongly supports the common origin of all life on Earth?

A)All organisms require energy.
B)All organisms use essentially the same genetic code.
C)All organisms reproduce.
D)All organisms show heritable variation.
E)All organisms have undergone evolution.

Question 47

Which of the following observations helped Darwin shape his concept of descent with modification?

A)Species diversity declines farther from the equator.
B)Fewer species live on islands than on the nearest continents.
C)Birds can be found on islands located farther from the mainland than the birds' maximum nonstop flight distance.
D)South American temperate plants are more similar to the tropical plants of South America than to the temperate plants of Europe.
E)Earthquakes reshape life by causing mass extinctions.

Question 48

Which of the following statements most detracts from the claim that the human appendix is a completely vestigial organ?

A)The appendix can be surgically removed with no immediate ill effects.
B)The appendix might have been larger in fossil hominids.
C)The appendix has a substantial amount of defensive lymphatic tissue.
D)Individuals with a larger-than-average appendix leave fewer offspring than those with a below-average-sized appendix.
E)In a million years, the human species might completely lack an appendix.

Question 49

Members of two different species possess a similar-looking structure that they use in a similar fashion to perform the same function. Which information would best help distinguish between an explanation based on homology versus one based on convergent evolution?

A)The two species live at great distance from each other.
B)The two species share many proteins in common, and the nucleotide sequences that code for these proteins are almost identical.
C)The sizes of the structures in adult members of both species are similar in size.
D)Both species are well adapted to their particular environments.
E)Both species reproduce sexually.

Question 50

DNA sequences in many human genes are very similar to the sequences of corresponding genes in chimpanzees. The most likely explanation for this result is that

A)humans and chimpanzees share a relatively recent common ancestor.
B)humans evolved from chimpanzees.
C)chimpanzees evolved from humans.
D)convergent evolution led to the DNA similarities.
E)humans and chimpanzees are not closely related.

Question 51

Ichthyosaurs were aquatic dinosaurs. Fossils show us that they had dorsal fins and tails, as do fish, even though their closest relatives were terrestrial reptiles that had neither dorsal fins nor aquatic tails. The dorsal fins and tails of ichthyosaurs and fish are

A)homologous.
B)examples of convergent evolution.
C)adaptations to a common environment.
D)A and C only
E)B and C only

Question 52

Monkeys of South and Central America have prehensile tails, meaning that their tails can be used to grasp objects. The tails of African and Asian monkeys are not prehensile. Which discipline is most likely to provide an evolutionary explanation for how this difference in tails came about?

A)Aerodynamics
B)Biogeography
C)Physiology
D)Biochemistry
E)Botany

Question 53

If two modern organisms are distantly related in an evolutionary sense, then one should expect that

A)they live in very different habitats.
B)they should share fewer homologous structures than two more closely related organisms.
C)their chromosomes should be very similar.
D)they shared a common ancestor relatively recently.
E)they should be members of the same genus.

Question 54

It has been observed that organisms on islands are different from, but closely related to, similar forms found on the nearest continent. This is taken as evidence that

A)island forms and mainland forms descended from common ancestors.
B)common environments are inhabited by the same organisms.
C)the islands were originally part of the continent.
D)the island forms and mainland forms are converging.
E)island forms and mainland forms have identical gene pools.

Question 55

Over evolutionary time, many cave-dwelling organisms have lost their eyes. Tapeworms have lost their digestive systems. Whales have lost their hind limbs. How can natural selection account for these losses?

A)Natural selection cannot account for losses, only for innovations.
B)Natural selection accounts for these losses by the principle of use and disuse.
C)Under particular circumstances that persisted for long periods, each of these structures presented greater costs than benefits.
D)The ancestors of these organisms experienced harmful mutations that forced them to find new habitats that these species had not previously used.

Question 56

Within a few weeks of treatment with the drug 3TC, a patient's HIV population consists entirely of 3TC-resistant viruses. How can this result best be explained?

A)HIV can change its surface proteins and resist vaccines.
B)The patient must have become reinfected with 3TC-resistant viruses.
C)HIV began making drug-resistant versions of reverse transcriptase in response to the drug.
D)A few drug-resistant viruses were present at the start of treatment, and natural selection increased their frequency.
E)The drug caused the HIV RNA to change.

Question 57

Which of the following is not an observation or inference on which natural selection is based?

A)There is heritable variation among individuals.
B)Poorly adapted individuals never produce offspring.
C)Species produce more offspring than the environment can support.
D)Individuals whose characteristics are best suited to the environment generally leave more offspring than those whose characteristics are less suited.
E)Only a fraction of the offspring produced by an individual may survive.