Deck 22: Evolution by Natural Selection

Question 1

A farmer uses triazine herbicide to control pigweed in his field. For the first few years, the triazine works well and almost all the pigweed dies; but after several years, the farmer sees more and more pigweed, no matter how often he applies triazine. Which of these actions is most likely to solve the farmer's problem?

A) adding triazine more often to his fields
B) trying a different herbicide
C) applying the triazine to the soil and roots instead of spraying it over the leaves
D) increasing the amount of triazine he puts on his fields

Answer 1

B

Question 2

Which of the following statements describes a vestigial trait?

A) Whales and dolphins must breathe air even though they spend their entire lives in the water.
B) Penguins are flightless birds with wings that are specialized for swimming.
C) Humans still have eyebrows, even though we have much less body hair than chimps.
D) Kiwis are flightless birds with reduced, nonfunctional wings.
E) Snakes have hinged jaws to help them swallow large meals.

Answer 2

D

Question 3

After the drought of 1977, researchers hypothesized that on Daphne Major, medium ground finches with large, deep beaks survived better than those with smaller beaks because they could more easily crack and eat the tough Tribulus cistoides fruits. If this hypothesis is true, what would you expect to observe if a population of these medium ground finches colonizes a nearby island where T. cistoides is the primary available food in all yea
Assume that 1) even the survivors of the 1977 drought sometimes had difficulty cracking the tough T. cistoides fr and would eat other seeds when offered a choice, and 2) food availability is the primary limit on finch fitness on this new island.

A) evolution of smaller, pointier beaks over time
B) random fluctuations in beak size and shape
C) evolution of yet larger, deeper beaks over time
D) no change in beak size and shape

Answer 3

C

Question 4

Radiometric dating is a technique used to determine the age of rocks. Geologists have used this technique to determine that

A) Earth is about 4.6 billion years old, and life appeared on Earth about 3.8 billion years ago.
B) Earth is about 3.4- 3.8 billion years old, and life appeared on Earth about 460 million years ago.
C) Earth is about 34- 38 billion years old, and life appeared on Earth about 4.6 billion years ago.
D) Earth is about 46 billion years old, and life appeared on Earth about 34- 38 billion years ago.

Question 5

Why was Darwin and Wallace's theory of evolution by natural selection revolutionary?

A) It proposed that humans were descended from chimpanzees.
B) It was the first time a biologist had proposed that species changed through time.
C) It dismissed the idea that species are constant and emphasized the importance of variation and change in populations.
D) It proved that individuals acclimated to their environment over time.

Question 6

Your text discusses the evolution of antibiotic- resistant M. tuberculosis bacteria in a patient. Researchers discovered that the strain of M. tuberculosis taken from the dead patient has a point mutation in the rpoB gene that codes for part of the RNA polymerase enzyme. This mutant form of RNA polymerase does not normally function as well as the more common form, but a commonly used antibiotic called rifampin does not affect the mutant rpoB. A researcher places M. tuberculosis isolated from the patient a year before death no rpoB mutation) in cell cultures with M. tuberculosis isolated from the dead patient with rpoB mutation). Half the cell cultures contain just standard nutrients, and the other cell cultures contain rifampin in addition to the standard nutrients. After many cell generations, the researcher finds that

A) almost all M. tuberculosis in the standard nutrient cell cultures carry the rpoB gene mutation, but very few of the M. tuberculosis in the cell cultures with rifampin carry the rpoB mutation.
B) a mix of both M. tuberculosis strains thrive in the standard cell cultures, but no living bacteria can be found in the cell cultures that contain rifampin.
C) very few M. tuberculosis in any of the cell cultures carry the rpoB gene mutation.
D) very few M. tuberculosis in the standard nutrient cell cultures carry the rpoB gene mutation, but almost all of the M. tuberculosis in the cell cultures with rifampin carry the rpoB mutation.
E) almost all of the M. tuberculosis in both types of cell cultures carry the rpoB mutation.

Question 7

The same basic internal organs kidneys, stomach, heart, lungs) are found in frogs, birds, snakes. and rodents. This is primarily an example of

A) transitional features.
B) genetic correlation.
C) developmental homology.
D) structural homology.

Question 8

Which of the following statements is an example of typological thinking?

A) Women are shorter than men, have longer hair, and like to shop.
B) The variety of dog shape and size is truly amazing.
C) The type of beak that is most advantageous varies depending on how much rain falls in a given year.
D) It is best to choose the seeds from the plants with the largest fruits to set aside for next year's plantings.

Question 9

Gill pouches in chick, human, and house- cat embryos are an example of

A) the inheritance of acquired characters.
B) structural homology.
C) developmental homology.
D) genetic homology.

Question 10

Researchers have found fossils of Eocene horse species in Colorado. Deeper deposits contain smaller species, and more recent deposits contain larger species. How does this observation support the theory of evolution?

A) It proves that environments have changed over time.
B) It suggests that species are unchanging and of recent origin.
C) It does not support the theory of evolution.
D) It shows that all species are related to each other.
E) It provides evidence that species change over time.

Question 11

Explain how one of the following supports the idea that species change through time: artificial selection, extinction, transitional forms, vestigial traits, or antibiotic resistance.

Question 12

Which of these conditions are always true of populations evolving due to natural selection?
Condition 1: The population must vary in traits that are heritable. Condition 2: Some heritable traits must increase reproductive success. Condition 3: Individuals pass on all traits they acquire during their lifetime.

A) Condition 1 only
B) Condition 2 only
C) Conditions 1 and 2
D) Conditions 2 and 3
E) Conditions 1, 2, and 3

Question 13

Why did Darwin argue that evidence of extinction supports the theory of evolution?

A) It shows that lower organisms have died to make way for humans.
B) It shows that nothing lasts forever.
C) It shows that reproduction is more important than survival of the fittest.
D) It shows that the number and types of species have changed over time.

Question 14

You sequence the genes that code for an important glycolytic enzyme in a moth, a mushroom, a worm, and an alga, and find a high degree of sequence similarity among these distantly related species. This is an example of

A) analogy/convergent evolution.
B) structural homology.
C) genetic homology.
D) developmental homology.

Question 15

A farmer uses triazine herbicide to control pigweed in his field. For the first few years, the triazine works well and almost all the pigweed dies; but after several years, the farmer sees more and more pigweed. Which of these explanations best describes this observation?

A) Triazine- resistant pigweed has less- efficient photosynthesis metabolism.
B) Increased rainfall due to climate change washes away the herbicide more often, so the pigweed has reduced exposure to the triazine.
C) The pigweed mutated in response to the herbicide, creating a new triazine- resistant species.
D) Only triazine- resistant weeds survived and reproduced, so each year more pigweed was triazine- resistant.

Question 16

If you say that Squirrel A has greater biological fitness than Squirrel B, you mean that the animal

A) is able to mate more frequently than Squirrel B.
B) has a longer lifespan.
C) has more offspring that survive to reproductive age than Squirrel B.
D) is able to access more food than Squirrel B.
E) is bigger and stronger than Squirrel B.

Question 17

Who proposed that organisms could be organized into a great chain of being?

A) Lamarck
B) Wallace
C) Aristotle
D) Darwin
E) Linnaeus

Question 18

Which of the following is the best modern definition of evolution?

A) change in allele frequencies in a population over time
B) inheritance of acquired characters
C) survival of the fittest
D) descent without modification

Question 19

Evolutionary theory predicts that species are related, not independent. Four of the following examples provide support for this prediction, but one is irrelevant. Which one of these examples does not support the claim that species are related?

A) The endostyle of lancelets invertebrate chordates) and the thyroid gland of vertebrates develop similarly, and both produce iodinated proteins.
B) Many dinosaurs and other organisms went extinct following a huge asteroid impact at the end of the Cretaceous.
C) Ground squirrel species found on the north and south sides of the Grand Canyon are very similar to each other.
D) All prokaryotes and eukaryotes use DNA to carry their genetic information.
E) Before synthetic insulin was available, diabetics used injections of purified pig insulin to manage their disease.

Question 20

Which of the following scientists argued that variation among individuals allows evolution to occur?

A) Lamarck
B) Aristotle
C) Wallace
D) Linnaeus

Question 21

Vestigial traits and neutral changes in DNA sequences are good examples of

A) convergent traits.
B) nonadaptive traits.
C) adaptation.
D) acclimation.
E) developmental homology.

Question 22

Figure 22.2
The distribution of pocket- mouse coat colours in several Arizona populations is associated with substrate colour Some populations live on light- coloured granite substrate, and others live on dark volcanic rock. In Figure 22.2, chart A shows the frequency of the melanic dark) coat phenotype across six populations. Populations C, D, and E live on dark volcanic rock; populations A, B, and F live on light- coloured granite. Chart B shows the
Frequency of the Melanocortin- 1 receptor Mc1r) allele across these populations. The Mc1r alleles, D and d, differ by four amino acids; mice with DD and Dd genotypes have dark coats, whereas mice with dd genotype are light coloured. Which of the following statements best interprets the results shown in charts A and B?

A) Frequency of the D allele is closely associated with both the melanic phenotype and the presence of dark substrate colour.
B) Frequency of the D allele is closely associated with the melanic phenotype, but is unrelated to the presence of dark substrate colour.
C) Frequency of the D allele is not associated with the melanic phenotype, but is associated with the presence of dark substrate colour.
D) Frequency of the D allele is associated neither with the melanic phenotype nor with the presence of dark substrate colour.
E) Frequency of the D allele does not vary.

Question 23

Which of the following is an example of acclimation?

A) Some animals grow thicker coats when exposed to low temperatures.
B) Some bacteria can use the energy from sunlight to make sugars.
C) Some fungi are larger than others are.
D) Some hemoglobins have a higher affinity for oxygen than others.
E) Some plant species can absorb nitrogen better than others can.

Question 24

This scenario is for the next questions).
You have a mixed population of bacteria S. aureus) in the lab. Approximately half of them WT) are susceptible to the antibiot rifampin. The other half are not, due to a mutation in the rpoB gene. The rpoB mutation results in an RNA polymerase that doesn't work as well as in the WT, hence transcription is not as rapid, and these bacteria grow much more slowly than those with the WT enzyme.
If the population is maintained on media that contains rifampin, what is expected to occur over a period of time?

A) The rifampin susceptible bacteria and the rifampin resistant bacteria will remain in approximately equal proportions.
B) The rifampin susceptible bacteria will increase in proportion to the rifampin resistant bacteria.
C) The rifampin resistant bacteria will increase in proportion compared to the rifampin susceptible bacteria.

Question 25

The following questions) are based on information in Hopi E. Hoekstra, Kristen E. Drumm, and Michael W. Nachman, "Ecological Genetics of Adaptive Color Polymorphism in Pocket Mice: Geographic Variation in Selected and Neutral Genes," Evolution 586), 2004: 1329- 41.
Figure 22.1

-Refer to Figure 22.1. In their investigation of natural selection on Mc1r alleles the gene that determines coat colour) in Arizona pocket mice, Hoekstra et al. determined the frequency of the D and d alleles in each population. They also determined the frequency of alleles for two neutral mitochondrial DNA genes genes that do not affect and are not linked to coat colour). Why did the researchers include the mitochondrial DNA genes as part of their experimental design?

A) Allele change for the neutral mitochondrial genes serves as an experimental group and gives information on any general background genetic difference among these populations.
B) Allele change for the neutral mitochondrial genes serves as an experimental group and gives information on coat- colour differences among these populations.
C) Allele change for the neutral mitochondrial genes serves as a control and determines coat- colour differences among these populations.
D) Allele change for the neutral mitochondrial genes serves as a control and gives information on any general background genetic difference among these populations.
E) None of the above answers apply.

Question 26

The following questions) are based on information in Hopi E. Hoekstra, Kristen E. Drumm, and Michael W. Nachman, "Ecological Genetics of Adaptive Color Polymorphism in Pocket Mice: Geographic Variation in Selected and Neutral Genes," Evolution 586), 2004: 1329- 41.
Figure 22.1

-The figure above shows the distribution of pocket- mouse coat colours in several Arizona populations found either on light- coloured granite substrate or on dark volcanic rock dark substrate). The Melanocortin- 1 receptor Mc1r) alleles, D and d, differ by four amino acids. Mice with DD and Dd genotypes have dark coats, whereas mice with the dd genotype are light coloured. What sort of genotype frequencies might you expect to find in the Xmas, Mid, and O'Neill populations?

A) Xmas-high DD frequency; Mid-high Dd frequency, O'Neill-high dd frequency
B) Xmas-high dd frequency; Mid-high Dd frequency, O'Neill-high DD frequency
C) Xmas-high Dd frequency; Mid-high DD frequency, O'Neill-high dd frequency
D) Xmas-high Dd frequency; Mid-high dd frequency, O'Neill-high DD frequency
E) Xmas-high dd frequency; Mid-high DD frequency, O'Neill-high Dd frequency

Question 27

A population of beetles lives on a forest floor, which is covered in dark leaf litter. Dark beetles have the genotype A₂A₂, while lighter beetles have an A₁A₁ genotype; heterozygotes have a phenotype that is closer to that of the A₁A₁ homozygotes. The oppresso bird preys on these beetles. What outcome do you predict?

A) Behaviours learned from the beetles will be passed onto their offspring.
B) Beetles will have darker- shelled offspring to protect them from predation.
C) The proportions of beetles in the population with different traits change over time.
D) The colour of each beetle within the population will gradually change over time.
E) A mutation will arise that will result in a darker shell colour and protect the beetles from predation.

Question 28

Read the scenario above. If the population is maintained on media that lacks rifampin, what is expected to occur over a period of time?

A) The rifampin resistant bacteria will increase in proportion compared to the rifampin susceptible bacteria.
B) The rifampin susceptible bacteria and the rifampin resistant bacteria will remain in approximately equal proportions.
C) The rifampin susceptible bacteria will increase in proportion to the rifampin resistant bacteria.

Question 29

Which of the following is an example of an environmental constraint on evolution by natural selection?

A) The availabilities of different types of food are inconsistent from year to year on Daphne Major, so finches with the "perfect" bill size in one year may be at a disadvantage in another year.
B) Dolphin embryos grow hindlimb buds during development, even though they do not have or need hindlimbs as adults.
C) Female humans have nipples with mammary glands; males have nipples too but are unable to produce milk.
D) Certain proteins in humans have similar amino acid sequences to those found in yeast because we have been unable to evolve more sophisticated sequences.
E) Hox genes are found in both Drosophila and humans and are important in the development of body parts.

Question 30

Tourist companies start visiting Island X, where the new colony of medium ground finches see previous question) feeds on the tough- fruited Tribulus cistoides. The tourist companies set up reliable feeding stations with a variety of bird seeds different types and sizes), so that tourists can get a better look at the finches. Which of these events is now most likely to occur to finch beaks on Island X?

A) evolution of smaller, pointier beaks over time, until all birds have relatively small, pointy beaks
B) no change in beak size and shape over time
C) increased variation in beak size and shape over time
D) evolution of yet larger, deeper beaks over time, until all birds have relatively large, deep beaks

Question 31

Which of the following is a fitness trade- off?

A) The largest male elephant seals are able to mate with many females, but smaller males rarely have the opportunity to mate.
B) Algal genotypes that can grow fast in nitrogen- limited environments are easier for predators to digest.
C) In some hornbill species, the male helps seal the female in a tree with her nest until the young are ready to fledge.
D) Moths are the best pollinators for datura flowers, but bees are the best pollinators for orchids.

Question 32

Evolution of antibiotic resistant bacteria represents which of the following?

A) naturalselection
B) genetic drift
C) reproductive selection
D) artificial selection

Question 33

Parasitic species tend to have simple morphologies. Which of the following statements best explains this observation?

A) Parasites are lower organisms, and this is why they have simple morphologies.
B) Simple morphologies have been naturally selected for in most parasites.
C) Parasites have not yet had time to progress, because they are young evolutionarily.
D) Parasites do not live long enough to inherit acquired characteristics.

Question 34

A patient has finished his treatment for a bacterial infection with an antibiotic and feels better. However, four days later the same bacterial infection returns. The doctor prescribes the same course of antibiotics, but this time these antibiotics do not cure the patient. What would be the most likely reason for this?

A) The patient was not treated in time and so the infection became too severe.
B) The non- resistant bacteria evolved within these four days so that the drug became ineffective.
C) The drug killed most of the bacteria in the population, but a few individuals with genetic resistance to the drug survived and passed the resistant gene on to their offspring.
D) The antibiotic was quickly metabolized by the patient and did not have time to work.

Question 35

Evolution by natural selection changes the population but not the individual.

Question 36

Use the following information when answering the corresponding questions).
The following questions) are based on information from Frank M. Frey, "Opposing Natural Selection from Herbivores and Pa May Maintain Floral- Color Variation in Claytonia virginica Portulacaceae)," Evolution 5811), 2004: 2426- 37.
Claytonia virginica is a woodland spring herb with flowers that vary from white to pale pink to bright pink. This plant is primarily pollinated by a bee that prefers pink flowers to white flowers. Claytonia with pink flowers have a greater relative fruit set than Claytonia with white flowers. Nevertheless, the percentage of different flower colours remains stable in the study population from year to year. Which of these statements might explain this observation?

A) Reproductive success does not affect evolution in this species.
B) The white flowers have evolved pollinator resistance.
C) Fitness is primarily determined by fruit set in this species.
D) Flower colour is not heritable, but is instead environmentally determined.

Question 37

According to the theory of evolution by natural selection, which of the following is FALSE?

A) The individuals that survive to reproduce are a random sample of the population.
B) Natural selection occurs at the level of the individual, but the changes evolution) are observed at the population level.
C) Individuals with certain heritable traits contribute more reproductively to the next generation than others without those traits.
D) Over- reproduction and limited resources leads to competition.

Question 38

Use the following information when answering the corresponding questions).
The following questions) are based on information from Frank M. Frey, "Opposing Natural Selection from Herbivores and Pa May Maintain Floral- Color Variation in Claytonia virginica Portulacaceae)," Evolution 5811), 2004: 2426- 37.
Claytonia virginica is a woodland spring herb with flowers that vary from white to pale pink to bright pink. Slugs prefer to eat pink- flowering over white- flowering plants due to chemical differences between the two), and plants experiencing severe herbivory are more likely to die. The bees that pollinate this plant also prefer pink to white flowers, so that Claytonia with pink flowers have a greater relative fruit set than Claytonia with white flowers. A researcher observes that the percentage of different flower colours remains stable in the study population from year to year. If the researcher removes all slugs from the study population, what do you expect to happen to the distribution of flower colours in the population over time?

A) The percentage of pink flowers should increase over time.
B) The percentage of white flowers should increase over time.
C) The distribution of flower colours should randomly fluctuate over time.
D) The distribution of flower colours should not change.

Question 39

A population of rabbits grows explosively because resources are high. However, now that numbers have increased substantially, there is not enough food for all individuals and the population is threatened. What will happen under such circumstances?

A) There will be competition for the food and some rabbits will not survive to reproduce.
B) A random group of the rabbits will survive and reproduce to form the next generation.
C) Some rabbits will move away to find another food source so that individuals remaining in the population will survive.
D) The rabbits will share the food with each other; if everyone gets a little bit of food, the population will survive.

Question 40

Figure 22.3
In Figure 22.3, chart X above shows the frequency of the most common neutral mitochondrial DNA allele an all gene that does not affect and is not linked to coat colour) across six pocket- mouse populations. Populations C, D and E live on dark volcanic rock; populations A, B, and F live on light- coloured granite. Compare this figure with chart Y above. What should you conclude after comparing these two figures?

A) The most common neutral mitochondrial DNA allele varies more among populations than the Mc1r D allele.
B) Little to no correlation exists between neutral mitochondrial DNA alleles and habitat colour.
C) The most common neutral mitochondrial DNA allele is strongly associated with the frequency of the Mc1r D allele.
D) The most common neutral mitochondrial DNA allele is strongly associated with substrate colour.

Question 41

Fishers typically target the largest, and thus, oldest fish. Given this fishing strategy, which of the following would be the most likely outcome due to natural selection over time on life history traits. Which of the following best predicts the effect of natural selection due to this fishing strategy on the life history traits of the commercially popular fish?

A) There would be no change in the life histories of these fish populations as a species' age at reproduction cannot change.
B) A greater proportion of the fish population would be made up of individuals that become reproductively mature at a larger size, and, thus, an older age.
C) A greater proportion of the fish population would be made up of individuals that become reproductively mature at a smaller size, and, thus, an earlier age.
D) A greater proportion of the fish population would be made up of individuals that become reproductively mature at a smaller size, and, thus, an older age.

Question 42

Which statement about transitional features is true?

A) Hemoglobin expression transitions from the fetus to newborn due to the requirement of hemoglobin in the fetus to be able to bind oxygen more tightly.
B) Transitional features show that natural selection sometimes plans ahead to achieve evolutionary goals in a species.
C) A bird's wing and a bat's wing are examples of transitional features.
D) Fossil species with transitional features are not necessarily direct ancestors of living species, but they are likely closely related to the ancestor.
E) Scientists have not yet discovered any examples of true transitional features.