Deck 3: Natural Selection

Question 1

According to the figure above,which of the following statements is true?

A)The percentage of fish found in larger groups increases as predation pressure increases.
B)The percentage of fish found in larger groups increases as predation pressure decreases.
C)The percentage of fish found in larger groups is not affected by changes in predation pressure.
D)None of the above

Answer 1

A

Question 2

Researchers studying variations in oldfield mouse coat color found that the light coat color of many beach populations was due to a

A)mutation in the Mc1R protein, which reduces the ability of a-MSH to bind.
B)mutation in the regulatory region of the Agouti gene, which increases ASP expression.
C)reduction in eumelanin production.
D)All of the above

Answer 2

D

Question 3

According to the figure above,plants with genotype 1

A)grow tall at high and low elevations but are short at medium elevations.
B)respond the same to each elevation.
C)grow tallest at medium elevations and shorter at high and low elevations.
D)B and C

Answer 3

A

Question 4

The experiment shown above demonstrates

A)the inheritance of acquired characteristics.
B)a selective disadvantage to mice with coats that match the color of their environment.
C)a selective advantage to mice with coats that match the color of their environment.
D)A and B
E)A and C

Question 5

The 2000-2004 drought in California

A)shortened the growing season of the mustard plant.
B)led to earlier flowering in the mustard plant.
C)created selective forces that changed the characteristics of the mustard plant.
D)A and C
E)All of the above

Question 6

Natural selection is a process by which

A)the characteristics of individuals change over time.
B)the characteristics of populations change over time.
C)Both of the above
D)None of the above

Question 7

A species' life history strategy refers to

A)the traits of an individual organism over its lifetime.
B)a schedule and manner of investment in survivorship over the lifetime of an individual.
C)a schedule and manner of investment in reproduction over the lifetime of an individual.
D)A and B
E)B and C

Question 8

Natural selection is the consequence of

A)variation.
C)differential reproductive success.
B)inheritance.
D)All of the above

Question 9

When evolutionary biologists study the process of natural selection,they focus on

A)what drives mutations.
B)how a trait of interest changes over time.
C)how a trait of interest remains constant over time.
D)A and B
E)B and C

Question 10

According to the figure above,which of the following statements is true?

A)Group size increases as predation pressure decreases.
B)Group size increases as predation pressure increases.
C)Group size is not affected by changes in predation pressure.
D)None of the above

Question 11

According to the figure above,which of the following statements is true?

A)Genotypes do not code for a fixed leaf size.
B)Genotypes do not code for a fixed leaf area.
C)Genotypes code for a number and area of leaves that depends on the intensity of light to which the plant is exposed.
D)All of the above

Question 12

The formal definition of "fitness" in evolutionary biology

A)pertains to relative reproductive success.
B)implies something is well matched or fit.
C)Both of the above
D)None of the above

Question 13

A trait that serves one purpose today but evolved under different selective conditions is

A)called an exaptation.
B)called an adaptation.
C)not favored by natural selection
D)A and C
E)B and C

Question 14

According to the figure above,which of the following statements is true?

A)Hybrids flowered later in the season than those from predrought populations.
B)Hybrids flowered earlier in the season than those from postdrought populations.
C)Hybrids flowered at intermediate times.
D)None of the above

Question 15

Genes affect traits

A)in only one environment.
C)by coding for them.
B)by producing a norm of reaction.
D)All of the above

Question 16

The guppy behavior studies presented in your text,including the experiments on transfering guppies between high predation and low predation sites,illustrate the

A)rapidity with which natural selection can operate.
B)significant differences in behavior that have evolved between populations over 10,000 years.
C)significant differences in behavior that have evolved within populations due to predation stress.
D)All of the above
E)None of the above

Question 17

In principle,the variations in oldfield mouse coat color illustrated in the figure above could result from

A)genetic differences.
B)environmental differences.
C)differences in diet.
D)exposure to sunlight.
E)All of the above

Question 18

Natural selection sorts on

A)phenotypic, not genotypic, differences in a population.
B)genotypic, not phenotypic, differences in a population.
C)both genotypic and phenotypic differences in a population.
D)None of the above

Question 19

Lenski and Travisano compared what happened to the size of cells in 12 replicate lines of E.coli.According to the graphs above,which of the following statements is (are)true?

A)There is competition for limited resources in nature.
B)Average cell volume decreased substantially over the first 2000 to 3000 generations.
C)Average cell volume increased substantially over the first 2000 to 3000 generations.
D)A and B
E)A and C

Question 20

According to the figure above,which of the following statements is true?

A)Descendant populations of the mustard plant growing after the severe 2000-2004 drought flowered earlier in the season than those from predrought populations.
B)Descendant populations of the mustard plant growing after the severe 2000-2004 drought flowered later in the season than those from predrought populations.
C)Hybrids flowered later in the season than those from predrought populations.
D)B and C
E)None of the above

Question 21

Why aren't organisms perfectly adapted to their environments?

A)There are physical constraints that cannot be overcome.
B)An organism's surroundings do not present a stationary target to which natural selection can optimize its phenotype.
C)The process of natural selection lacks foresight.
D)All of the above
E)None of the above; some organisms are perfectly adapted to their environments.

Question 22

In the situation above,what could you do in addition to hypothesizing that particular reproductive strategies would occur? If they did occur,how would you determine that those reproductive behaviors are the result of adaptation to specific predation pressures?

Question 23

Compare the placement of eyes in an ostrich to that in an owl.What are the trade-offs in physical constraint that each faces?

Question 24

The text presents the experiments of Richard Lenski and his colleagues,who set up long-range experiments on E.coli.In the experiment illustrated in the figure above,12 parallel E.coli lineages were created and maintained,cells from each line were periodically frozen,and the team followed the lineages for more than 50,000 generations.Why were these experiments groundbreaking? How have these experiments revolutionized the sorts of questions evolutionary biologists can ask?

Question 25

An exaptation is a

A)trait originally selected for one function but later co-opted for another.
B)trait of seemingly little importance.
C)gene that codes for beneficial effects in one environment and deleterious effects in other environments.
D)All of the above
E)None of the above

Question 26

How can we explain the exquisite complexity of some complex traits,such as the vertebrate eye?

A)Each intermediate step toward the evolution of complex traits was itself adaptive.
B)Intermediate stages of complex traits were functional and selected for in the past but were selected for a function other than that observed today.
C)A and B
D)None of the above

Question 27

Explain the figure above,including how the study graphed here illustrates the concept of "norm of reaction."

Question 28

Considering the phylogenetic evidence that feathers evolved prior to flight,what might have been the original function of feathers?

A)Heat retention
B)Facilitating tactile sensation
C)Waterproofing
D)Shielding from sunlight
E)All of the above

Question 29

What are the three conditions that must be met in order for natural selection to occur? Briefly describe why these conditions are necessary components of natural selection.

Question 30

The figure above illustrates the findings of an observation study examining the selection pressure of predation on group size and behavior in guppies.Interpret the graphs,and explain the results.

Question 31

Imagine you are an evolutionary biologist studying reproductive trade-offs in populations of guppies that have been separated by the formation of barrier waterfalls.The upstream population faces lower predation than the downstream population,and the predators on the downstream side are larger and can eat any guppy offspring,no matter the size.Make a prediction about the reproductive strategies you might find and explain the trade-offs faced by the reproducing female guppies on each side of the barrier.

Question 32

Explain how natural selection has played an essential role in driving the modifications that have lead to the incredible biodiversity of life on Earth.

Question 33

Lenski and Travisano compared what happened to the fitness of cells in 12 replicate lines of E.coli.According to the graphs above,which of the following statements is (are)true?

A)After only 500 generations, natural selection had already increased fitness in the evolving strains.
B)Average fitness decreased substantially over the first 2000 to 3000 generations.
C)Average fitness increased substantially over the first 2000 to 3000 generations.
D)A and B
E)A and C

Question 34

The antagonistic pleiotropy hypothesis proposes that

A)separate genes code for beneficial effects in one environment and deleterious effects in other contexts.
B)the same gene(s) that code for beneficial effects also code for deleterious effects in other contexts.
C)mutational accumulation explains fitness declines over generations within a constant environment.
D)None of the above

Question 35

The term for a simultaneous action of natural selection on each side of the host-pathogen interaction is known as a(n)

A)evolutionary arms race.
C)antagonistic pleiotropy.
B)mutualism.
D)trade-off.

Question 36

Gene sharing is

A)one way that a new molecular function can arise.
B)another form of gene duplication.
C)is a form of molecular exaptation.
D)A and B
E)A and C

Question 37

The results of the Lenski and Travisano experiment on cells in 12 replicate lines of E.coli illustrate the fact that

A)evolution by natural selection is sometimes significantly affected by chance events, such as random mutations, and the order in which they happen.
B)evolution by natural selection is often a predictable, repeatable process.
C)A and B
D)None of the above

Question 38

Why do exaptations provide challenges to evolutionary biologists' attempts to generate testable hypotheses about how natural selection produces adaptations?

Question 39

Evolutionary change in one species that affects the selective conditions for a second species is known as

A)an evolutionary arms race.
C)antagonistic pleiotropy.
B)coevolution.
D)a trade-off.

Question 40

Geological evidence reveals that the barrier islands where the populations of oldfield mice shown in the figure above occur formed only 6000 years ago.Presumably,divergence in coat color occurred after the islands' formation (Hoekstra et al.2006).Explain how these dramatic variations in coat color between populations could have evolved over such a short period relative to the scale of evolutionary time.

Question 41

What is meant by the statement "Natural selection lacks foresight"?

Question 42

Describe some ways in which,at the molecular level,the process of evolution tinkers with existing structures to produce novel functions.

Question 43

In the figure above,you can see that if we compare leg diameter to body mass in mammals,from the shrew to the elephant,all conform to a tightly defined relationship,even across a million-fold difference in body mass.Why is this so?

Question 44

Based on the figure above,use phylogenetic reasoning to explain whether feathers evolved for flight,and why.What other possible advantages could feathers provide? Is there a way to determine which was the original selective function? Explain your answer.

Question 45

Darwin proposed that the sutures in the skulls of young mammals were wonderfully adapted to aid in the passage through the birth canal,but he also argued that they could not have been originally adapted for that purpose.Studying the figure above,explain what evidence allowed Darwin to make that argument?