Deck 7: Life History

Question 1

Which statement about clownfish is true?

A) Most clownfish that live in the same anemone are related to one another.
B) Most clownfish spend considerable portions of their adult lives outside of an anemone.
C) Clownfish may help the anemone by eating its parasites.
D) Clownfish cannot live outside of an anemone.

Answer 1

C

Question 2

Four clownfish individuals of the species Premnas biaculeatus live in a single anemone. Albert measures 15 cm, Barry is 12 cm, Cindy is 8 cm, and Diane is 6 cm. Based on what you know about clownfish biology, which statement is most likely true?

A) Albert is the only female.
B) Barry is the only female.
C) Diane is the only female.
D) Cindy and Diane are both females.

Answer 2

A

Question 3

Four clownfish individuals of the species Premnas biaculeatus live in a single anemone. Albert measures 15 cm, Barry is 12 cm, Cindy is 8 cm, and Diane is 6 cm. Based on what you know about clownfish biology, which statement is most likely true?

A) Albert is the only breeding male.
B) Barry is the only breeding male.
C) Albert and Barry are both breeding males.
D) Cindy and Diane are both breeding females.

Answer 3

B

Question 4

Four clownfish individuals of the species Premnas biaculeatus live in a single anemone. Albert measures 15 cm, Barry is 12 cm, Cindy is 8 cm, and Diane is 6 cm. If Barry died, which of the following would most likely happen?

A) Albert would become a breeding male.
B) Albert would change from male to female.
C) Cindy would become a breeding male.
D) Cindy would become a female.

Question 5

Which statement about life histories is false?

A) For most organisms, some life history variation within the species is determined genetically.
B) The life history strategy of a species consists of the nature and timing of life history events averaged across all individuals in the species.
C) The variation in life history within the species Homo sapiens makes it impossible to make generalizations about the life history of the species as a whole.
D) Heritable variation in life history is the raw material on which natural selection can act.

Question 6

Refer to the table.
Three different genotypes of garter snakes (A, B, and C) were reared at different temperatures. Four individuals were in each trial. The table presents their weights (in grams). Based on these data, which genotype appears to show phenotypic plasticity?

A) Genotype A only
B) Genotype B only
C) Genotype C only
D) None of the genotypes

Question 7

Which of the following is a specialized form of phenotypic plasticity?

A) Anisogamy
B) Morphs
C) Isogamy
D) Direct development

Question 8

Refer to the figure.


- The figure shows the relationship between the trunk diameter and the leaf mass of ponderosa pine trees from both moist and desert climates. According to the figure, a tree in a desert climate with a trunk diameter of about 40 cm would have about the same leaf mass as a tree in a cool, moist climate whose trunk diameter is about _______ cm.

A) 10
B) 20
C) 30
D) 40

Question 9

Refer to the figure.


- The figure shows the relationship between the trunk diameter and the leaf mass of ponderosa pine trees from both moist and desert climates. According to the figure, a tree in a desert climate with a trunk diameter of 30 cm would have about _______ leaf mass of a tree with a trunk diameter of 10 cm. (Note the log-log scale.)

A) 2 times less
B) 4 times less
C) 8 times more
D) 20 times more

Question 10

Refer to the figure.


-The figure shows the relationship between the trunk diameter and the leaf mass of ponderosa pine trees from both moist and desert climates. Which statement comparing ponderosa pines grown in desert environments to those grown in cooler, moister climates is false?

A) Desert ponderosa pines have lower photosynthetic rates.
B) Desert ponderosa pines allocate less biomass to leaf production.
C) For a given height, desert ponderosa pines have thinner trunks.
D) Desert ponderosa pines have fewer branches.

Question 11

If tadpoles of spadefoot toads are fed shrimp and other tadpoles, they will most likely develop into the _______ morph and thus will likely have an advantage in _______ pools.

A) carnivore; ephemeral
B) carnivore; long-lasting
C) omnivore; ephemeral
D) omnivore; all

Question 12

In many species of Drosophila, flies of any genotype that are reared in a cold environment tend to be larger than flies of the same genotype raised in a warm environment. Is this an adaptation?

A) Yes, because phenotypic plasticity is always adaptive.
B) Yes, but only if there is evidence of allometry.
C) Maybe, but confirming this would require further experiments examining survival and reproduction of different sized flies.
D) Maybe, but confirming this would require further experiments examining whether the differences in size are genetic.

Question 13

A unicellular sexual ciliate has seven different mating types that produce gametes of roughly the same size. Any gamete from any given mating type can fuse with any other gamete, except for one of its own mating type. These ciliates are exhibiting

A) anisogamy.
B) isogamy.
C) monogamy.
D) phenotypic plasticity.

Question 14

Refer to the figure.
A major reason evolutionary biologists have puzzled over the ubiquity of sexual reproduction is often referred to as "the cost of males," which refers to the simple argument that the offspring of asexual females can produce offspring themselves, whereas only half of the offspring of sexual females can do so. Based on the model in the figure, what proportion of individuals in the 4^th generation will be asexual?

A) 70%
B) 75%
C) 80%
D) 99%

Question 15

Refer to the figure.
This figure presents data from a laboratory experiment using the nematode worm Caenorhabditis elegans and its lethal bacterial pathogen Serratia marcescens. Which of the following is not a reasonable inference from this figure?

A) When the pathogen is present in the environment, selection favors the production of more genetically variable offspring.
B) Selection for resistance to pathogens may counterbalance the cost of males in explaining why sexual reproduction is so widespread among organisms.
C) There is genetically based variation in C. elegans populations for outcrossing frequency.
D) In wild populations of C. elegans, outcrossing rates likely tend to be between around 70-90%.

Question 16

Refer to the figure. The figure shows the results of an experiment where wild type and obligate selfing (i.e. self-fertilizing) C. elegans nematode worms were reared across many generations, with and without their lethal bacterial pathogen, Serratia marcescens. Which of the following is not a reasonable inference from this figure?

A) C. elegans populations with very limited genetic variation are more vulnerable to pathogens.
B) Outcrossing may be advantageous only under particular conditions.
C) After 30 generations, mortality rate from S. marcescens for a treatment "Wild type (no bacteria)" would probably be around 0%.
D) After 30 generations, mortality rate from S. marcescens for a treatment "Wild type (no bacteria)" would probably be around 100%.

Question 17

All plants and some algae have a complicated life cycle that includes both a multicellular diploid _______ stage and a multicellular haploid _______ stage. This type of life cycle is called _______.

A) sporophyte; gametophyte; metamorphosis
B) sporophyte; gametophyte; alternation of generations
C) gametophyte; sporophyte; alternation of generations
D) gametophyte; sporophyte; metamorphosis

Question 18

In most plants, the mature sporophyte is _______ and is _______ the mature gametophyte.

A) haploid; much larger than
B) diploid; much smaller than
C) haploid; about the same size as
D) diploid; much larger than

Question 19

Which statement about the impacts of climate change on the snowshoe hare is true?

A) Hare fall coat color change has kept pace with the delay in snowfall.
B) The number of days of camouflage mismatch has increased.
C) Camouflage mismatch makes the hares harder for predators to see.
D) Camouflage mismatch is a problem for hares in the winter, but not in the summer.

Question 20

Which statement about David Lack's study on geographic variation in clutch size in birds is true?

A) Lack's analysis led to experiments supporting the hypothesis that there is a trade-off between egg number and offspring survivorship.
B) Lack's results stimulated the development of Charnov's dimensionless ratio c for comparing maturation rates of different species.
C) Lack found that clutch size for birds tends to be higher closer to the equator, where more food is available.
D) On a global scale, Lack found a strong longitudinal trend in clutch size.

Question 21

Refer to the figure.


- Seedlings of an annual plant were split into two equal treatment groups; in one group, extra fertilizer was added, and in the other group (the control group), no additional fertilizer was added. The numbers of seeds and the average weight of the seeds from each individual plant were monitored, and these data were plotted (each point represents an individual plant). According to the figure, it appears that fertilizer treatment _______ seed size and _______ seed number.

A) increased; had no effect on
B) increased; increased
C) had no effect on; decreased
D) decreased; increased

Question 22

Refer to the figure.


- Seedlings of an annual plant were split into two equal treatment groups; in one group, extra fertilizer was provided, and in the other group (the control group), no additional fertilizer was added. The numbers of seeds and the average weight of the seeds from each individual plant were monitored, and these data were plotted (each point represents an individual plant). Which statement best describes the results of this study?

A) Trade-offs between seed size and seed number exist in both the control and the fertilizer groups, and these trade-offs are of roughly equal magnitude.
B) Trade-offs between seed size and seed number exist in both the control and the fertilizer groups, but these trade-offs are much larger in the fertilizer group.
C) A trade-off between seed size and seed number exists in the control group but not in the fertilizer group.
D) A trade-off between seed size and seed number exists in the fertilizer group but not in the control group.

Question 23

Which statement about size-number trade-offs is true?

A) Size-number trade-offs are rarely, if ever, seen in organisms that lack parental care.
B) Size-number trade-offs are seen in animals, but rarely in plants.
C) Size-number trade-offs are rarely observed when comparing different animal species that have parental care.
D) Size-number trade-offs can result in different average egg or offspring sizes for different populations of a species evolving under different predation or climatic regimes.

Question 24

Based on the results of Sinervo's experiments with western fence lizards, what would be the most likely evolutionary consequence if levels of predation were reduced in a population that had previously experienced much predation?

A) Sprint speed would increase.
B) Egg size would increase.
C) The number of eggs per clutch would increase.
D) Average development time would slow down.

Question 25

In Sinervo's experiments with western fence lizards, why did he insert a syringe into some of the eggs but not remove any of the yolk?

A) To improve the survival rate
B) To induce development
C) To retard development
D) As a control

Question 26

Refer to the figure.
Based on the figure, bird species with annual fecundity around 3 have an annual survival rate that is around

A) 45-65% of the annual survival rate for bird species with annual fecundity of just 1.
B) 65-85% of the annual survival rate for bird species with annual fecundity of just 1.
C) twice the annual survival rate for bird species with annual fecundity between 6 and 7.
D) half the annual survival rate for bird species with annual fecundity between 6 and 7.

Question 27

Parental care is an important form of reproductive investment in some species, such as birds. Which of the following is not likely to be associated with a higher level of parental care?

A) Increased offspring weight
B) Increased offspring survival
C) Increased parental mortality
D) Increased parental weight

Question 28

In cod fishing, older and larger fish are more likely to be retained in nets than younger and smaller fish. Despite the removal of these large breeders, the population is still reproducing. How do you think cod characteristics have changed due to the selection pressure from over-fishing?

A) Selection has led to increased growth rates.
B) Selection has led to decreased growth rates.
C) Selection has led to decreases in the size of fish at the age of maturity.
D) Selection has led to increases in the age of fish at the age of maturity.

Question 29

Suppose a fish has just reached sexual maturity and is able to produce 10 eggs per month. It can either reproduce immediately or it can continue to grow. If it continues to grow, it can increase the number of eggs it can produce by 5 per month for every month it delays reproduction. If it delays reproduction for another 6 months, it can lay _______ eggs each month. It could have produced _______ eggs if it had started reproducing immediately and produced eggs for all of those six months.

A) 30; 30
B) 30; 60
C) 40; 30
D) 40; 60

Question 30

For which organism would it be advantageous to allocate more resources to reproduction than to growth?

A) One with a long life span
B) One in which fecundity increases with increased body size
C) One with low adult survival rates
D) One in which offspring survival is very low

Question 31

Refer to the figure.
Male fruit flies spend more time courting virgin females than recently mated females. Based on this fact and the accompanying figure, which of the following is not a reasonable inference?

A) There is a positive correlation between male body size and male lifespan.
B) Increased sexual activity may shorten the lifespan of small males.
C) Increased sexual activity may shorten the lifespan of large males.
D) Virgin females are smaller than mated females.

Question 32

Endosperm in plants serves a function much like _______ in animals.

A) metamorphosis
B) the egg yolk
C) isogamy
D) dormancy

Question 33

In comparison to that of other apes, the face of an adult human retains a juvenile appearance. We can thus say that the human face

A) is sequentially hermaphroditic.
B) is paedomorphic.
C) displays a niche shift.
D) is isomorphic.

Question 34

A species of turtle grows for several years before becoming sexually mature. It mates, reproduces, and dies soon afterward. This species of turtle would best be described as

A) sporophytic.
B) gametophytic.
C) iteroparous.
D) semelparous.

Question 35

The term "r-selection" refers to selection

A) that increases age at sexual maturity.
B) under crowded conditions.
C) for high population growth rates.
D) for iteroparity.

Question 36

Which organisms would be most likely to be K-selected?

A) Mice
B) Weedy plants
C) Mayflies
D) Lions

Question 37

Which statement about the r-K continuum is true?

A) Most species are at one extreme or the other.
B) Most species are intermediate between the two extremes.
C) The distinction between r- and K-selection is more useful for comparisons of distantly related species than of closely related species.
D) The r- and K-selection classification system makes sense for thinking about plant life histories, but not for mobile animals.

Question 38

According to Grime's classification scheme, processes that destroy plant biomass are called

A) semelparous factors.
B) stresses.
C) disturbances.
D) competitive factors.

Question 39

Evergreen foliage would most likely be found in which of Grime's categories of plants?

A) Stress-tolerant
B) Ruderal
C) Ontogenetic
D) Competitive

Question 40

According to Grime, under conditions of low stress and low disturbance _______ plants should predominate.

A) ruderal
B) ontogenetic
C) stress-tolerant
D) competitive

Question 41

Which classification scheme or metric is generally most helpful for comparing life histories across broad ranges of size or taxonomy?

A) Charnov's dimensionless ratio (c)
B) Grime's triangular model
C) The alternation of generations model
D) The r-K continuum

Question 42

Suppose that the average adult life span of a gorilla is 25 years and that these animals reach sexual maturity at 5 years of age. Which organism would have a similar value of c (Charnov's dimensionless ratio) to that of a gorilla?

A) A fish species that reaches sexual maturity at 6 months and has an average adult life span of 6 months
B) A bird that reaches sexual maturity at 2 years and has an average adult life span of 10 years
C) A turtle that reaches sexual maturity at 10 years and has an average adult life span of 20 years
D) None of the above as the dimensionless ratio cannot be used to compare such diverse organisms.

Question 43

Sequential hermaphroditism and paedomorphic development are both adaptations that allow individuals to take advantage of

A) the lack of females in the population.
B) conditions that are most favorable for reproduction.
C) opportunities to avoid predators.
D) dispersal abilities.

Question 44

Which statement about clownfish is false?

A) Clownfish are exceptional, since sequential hermaphroditism is extremely rare among fish.
B) If two individual clownfish in the same anemone are very similar in size, they will typically fight until one or the other is killed or driven away from the anemone.
C) If the breeding male clownfish is removed, the next largest individual will grow just enough to take the place of the breeding male.
D) The number of eggs a clownfish can produce is proportional to its size.

Question 45

Refer to the figure.
This figure is based on data from a study of how ambient temperature during development affects adult body size. The figure shows data for individuals of a single genotype in a single species. A total of 20 individuals were raised under different temperature treatments.

-The blue bars show the average body size of individuals for each temperature treatment, and the black bars provide a measure of the variation in body size recorded for each treatment. Which developmental temperature led to the highest variability in offspring size? Which temperature led to the lowest variability in offspring size? How did you assess the effect of temperature on body size variation? What is the term that best describes this pattern?

Question 46

Refer to the figure.
This figure is based on data from a study of how ambient temperature during development affects adult body size. The figure shows data for individuals of a single genotype in a single species. A total of 20 individuals were raised under different temperature treatments.

-The blue bars show the average body size of individuals for each temperature treatment, and the black bars provide a measure of the variation in body size recorded for each treatment. Suppose that this species is an animal. In this animal species, larger individuals have a much higher reproductive output, but smaller individuals are better at surviving unpredictable weather (especially colder temperatures). Over a long time scale, how might the average size of individuals of this species be affected by the predictability of average temperatures?

Question 47

Refer to the figure.


-The figure is based on data from a study of the body size and reproductive output of individual females of two different species (species 1 and species 2) over time. Each figure illustrates the growth and reproduction of each individual over its life span. Based on the body size and reproductive output of these two individuals, is there any evidence of a trade-off? Describe evidence that you think supports or does not support the hypothesis that there is a trade-off.

Question 48

Refer to the figure.


- The figure is based on data from a study of the body size and reproductive output of individual females of two different species (species 1 and species 2) over time. Each figure illustrates the growth and reproduction of each individual over its life span. Suppose that body size is positively correlated with egg size. Which species do you predict would produce larger eggs? Why?

Question 49

Refer to the figure.


- The figure is based on data from a study of the body size and reproductive output of individual females of two different species (species 1 and species 2) over time. Each figure illustrates the growth and reproduction of each individual over its life span. Suppose that the patterns in the figures stay as they are, but that the number of eggs are instead the number of seeds of different plant species. If smaller individuals produce smaller seeds, which species would you expect to have higher dispersal capabilities? Explain your reasoning.

Question 50

Refer to the figure.


-The figure is based on data from a study of the body size and reproductive output of individual females of two different species (species 1 and species 2) over time. Each figure illustrates the growth and reproduction of each individual over its life span. Assuming these individuals are representative of their species, compare the life span and lifetime reproduction of these two species. How long did each individual survive? Compare the overall lifetime reproductive output of each individual. Which species has higher overall reproductive output, and how many eggs would the individual produce?

Question 51

Refer to the figure.


- The figure is based on data from a study of the body size and reproductive output of individual females of two different species (species 1 and species 2) over time. Each figure illustrates the growth and reproduction of each individual over its life span. What type of reproductive strategy (semelparous or iteroparous) do these two individuals show? How did you determine this?

Question 52

Refer to the figure.


-The figure is based on data from a study of the body size and reproductive output of individual females of two different species (species 1 and species 2) over time. Each figure illustrates the growth and reproduction of each individual over its life span. Based on growth patterns and the timing of reproduction, which species is closer to the K end of the r-K continuum, and which is closer to the r end of the continuum? Explain.

Question 53

Refer to the figure.


- The figure is based on data from a study of the body size and reproductive output of individual females of two different species (species 1 and species 2) over time. Each figure illustrates the growth and reproduction of each individual over its life span. Based on these data, what appears to be the primary factor influencing when these individuals reach their highest reproductive output? Explain your reasoning.

Question 54

Refer to the figure.


- The figure is based on data from a study of the body size and reproductive output of individual females of two different species (species 1 and species 2) over time. Each figure illustrates the growth and reproduction of each individual over its life span. Suppose that successful reproduction in a given year is dependent on an individual's ability to secure a high-quality territory. In which species is it more important for females to secure a territory at a younger age? Why?

Question 55

Four clownfish individuals of the species Premnas biaculeatus live in a single anemone. Alex measures 12 cm, Blaine is 22 cm, Casey is 18 cm, and DJ is 10 cm. Which one is most likely the breeding male?

A) Casey
B) Blaire
C) Alex
D) DJ

Question 56

A young clownfish is just returning to the reef and is looking for an anemone to live in. He is currently 23 mm long. Which one would provide him with the best chances of survival?

A) A large anemone with five residents that are 60 mm, 54 mm, 42 mm, 33 mm, and 24 mm long
B) A small anemone with three residents that are 41 mm, 31 mm, and 25 mm long
C) A medium anemone with three residents that are 54 mm, 45 mm, and 36 mm long
D) A very small anemone with only one resident that is 27 mm long

Question 57

Which of the following pairs of items does not represent distinct stages of a life cycle?

A) A tadpole and a frog
B) A mosquito larva and a blackfly larva
C) A moss gametophyte and a moss sporophyte
D) A maple tree and a maple tree seed

Question 58

Refer to the table.
Three different genotypes of garter snakes (D, E, and F) were reared at different temperatures. Four individuals were in each trial. The table shows their weights (in grams). Based on these data, which genotype(s) appear(s) to show phenotypic plasticity?

A) Genotype D only
B) Genotype E only
C) Genotype F only
D) Genotypes D and E

Question 59

If sexual reproduction is favored in Species X (which can reproduce both sexually and asexually) because it results in greater genetic diversity that facilitates resistance to pathogen Y, then one would predict that

A) in the absence of pathogen Y, outcrossing would not be favored.
B) in the absence of pathogen Y, outcrossing would be favored.
C) in the presence of pathogen Y, self-fertilization would be favored.
D) in the presence of pathogen Y, outcrossing would not be favored.

Question 60

The type of complex life cycle that includes both multicellular haploid (gametophyte) and multicellular diploid (sporophytes) is known as

A) metamorphosis.
B) iteroparous.
C) alternation of generations.
D) sequential hermaphroditism.

Question 61

A particular fish species' larger offspring are less vulnerable to predators. If their offspring are not eaten, then their survival and eventual reproductive success is independent of their size upon emerging from the egg. Based on this scenario, which of the following is not a reasonable prediction?

A) Fish living in lakes with predators produce larger eggs than in lakes without predators.
B) Fish living in lakes with predators produce more eggs than in lakes without predators.
C) Fish living in lakes without predators produce more eggs than in lakes with predators.
D) Fish living in lakes without predators produce smaller eggs than in lakes with predators.

Question 62

Parental care is an important form of reproductive investment for some species. Which of the following is likely to be associated with a higher level of parental care?

A) Decreased parental mortality
B) Increased offspring survival
C) Increased offspring mortality
D) Increased parental weight

Question 63

Suppose a fish has just reached sexual maturity and is able to produce 10 eggs per month. It can either reproduce immediately or it can continue to grow. If it continues to grow, it can increase the number of eggs it can produce by 10 per month for every month it delays reproduction. If it delays reproduction for another 6 months, it can lay _______ eggs each month. It could have produced _______ eggs if it started reproducing immediately and produced eggs for all of those six months.

A) 30; 60
B) 40; 30
C) 70; 30
D) 70; 60

Question 64

Which of the following is not a benefit provided by dispersal?

A) Escape from predators and/or pathogens
B) Reduced competition among close relatives
C) Ability of organisms to move to favorable habitats
D) Opportunity to take advantage of generations of local adaptation

Question 65

Based on the findings of Hansen, which statement about marine gastropods is true?

A) The average geographic range of direct-developing species is larger than that of species with swimming larval stages.
B) The average geographic range of direct-developing species is smaller than that of species with swimming larval stages.
C) According to the fossil record, species with swimming larvae were more prone to extinction than direct-developing species.
D) According to the fossil record, species with swimming larvae had smaller geographic ranges and were therefore less prone to extinction.

Question 66

Perennial plants that live multiple years and reproduce each year are

A) metamorphic.
B) paedomorphic.
C) iteroparous.
D) semelparous.

Question 67

The term "K-selection" refers to selection

A) to increase age at sexual maturity.
B) in populations that tend to be close to the carrying capacity of the environment.
C) for high population growth rates.
D) for semelparity.

Question 68

According to Grime's classification of plants, which category of plants would most likely experience low stress but high disturbance?

A) Ruderal
B) Stress-tolerant
C) Paedomorphic
D) Competitive

Question 69

Suppose the average adult life span of a shorebird is 15 years, and these shorebirds reach sexual maturity at 5 years of age. Which organism would have a value of c (Charnov's dimensionless ratio) most similar to that of these birds?

A) A fish species that reaches sexual maturity at 6 months and has an average adult life span of 6 months
B) A robin that reaches sexual maturity at 2 years and has an average adult life span of 10 years
C) A turtle that reaches sexual maturity at 10 years and has an average adult life span of 30 years
D) A lion that reaches sexual maturity at 3 years and has an average adult life span of 8 years