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231 Cards in this Set
- Front
- Back
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1. Every four years, lemmings make a suicidal rush to the sea in an altruistic behavior that reduces
population density. A) True B) False |
False
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2. Who first drew the attention of the scientific community to the regularity of some population
cycles? |
B) Charles Elton
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3. Sheep and algae differ markedly in volatility of population size in the face of environmental
fluctuations. Why? |
A) Sheep are larger and thus have greater homeostatic resistance to physiological effects of
environmental change. B) Sheep are longer�]lived, and their populations consist of individuals born over a long period. This evens out effects on population size of short�]term fluctuations in birth rate. C) Both A and B contribute to this difference.���� |
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4. Long term data from trapping records or censuses of various large animals from gyrfalcons to
grouse have revealed:D |
C) pronounced and regular population cycles.
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5. Studies of the 1947-1949 commercial whitefish catch in Lake Erie revealed that:
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C) each year�s catch was dominated by individuals recruited in a single previous year (1944).r��
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6. Research in a virgin forest stand near Hearts Content, Pennsylvania, revealed irregular patterns
of recruitment of trees into the current stand. Which of the following species showed the most uniform pattern of establishment over the nearly 400-year record? |
C) shade�]tolerant beech
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7. Natural populations fluctuate through time. One of the forces causing variation in population
size is variation in the physical environment, which can have both direct and indirect effects on populations. Variation in population size linked to environmental fluctuation (aside from daily, lunar, and seasonal cycles) is likely to be:fference.���� |
A) irregularlton
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8. Natural populations fluctuate through time. Inherent dynamic properties can cause variations
in population size. Variation in population size linked to such properties is likely to be: |
B) periodic.lton
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9. An intrinsic population attribute that may be responsible for regular cycling of natural
populations is: |
D) a time delay in the response of birth and death rates to changes in the environment.
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10. In a discrete�]time population model with an intrinsic rate of natural increase (R) less than 1, the
population size: |
A) returns without fluctuation to carrying capacity.
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11. In a discrete�]time population model with an intrinsic rate of natural increase (R) between 1 and
2, the population size: |
B) exhibits damped oscillations around carrying capacity.
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12. In a discrete�]time population model with an intrinsic rate of natural increase (R) much greater
than 2, the population size:��� |
D) exhibits chaotic behavior.�w
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13. Stable oscillations of a population about its long�]term carrying capacity are called:4).r��
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C) limit cycles.
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14. Several moth populations have dynamics described best by a continuous�]time logistic model
with a time delay. The populations have values for the product of r (intrinsic rate of natural increase) and �� (time delay) shown below. In which of these populations would one expect increase or decrease to the carrying capacity (K) without overshooting it? |
A) moth A: r� = 0.2beech
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15. Several fish populations have dynamics described best by a continuous�]time logistic model with
a time delay. The populations have values for the product of r (intrinsic rate of natural increase) and �� (time delay) shown below. In which of these populations would one expect damped oscillations? |
B) fish B: r� = 1.0beech
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16. A population has dynamics best described by a continuous�]time logistic model with a time
delay. If this population is exhibiting limit cycles, the periods (measured from population peak to population peak) should be anywhere from 4 to about 5 . If this population cycles with a period of 10 years, what would be the approximate time delay, to the nearest year? |
C) 2 yearsycles.
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17. In Nicholson's experiments with sheep blowflies, stable limit cycles were observed for adults
when: |
B) larvae were provided a limited food supply while adults were provided unlimited food.
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18. What was the intrinsic time delay in Nicholson�s experiment with sheep blowflies?od.
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B) the larval development period
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19. Nicholson was able to eliminate population fluctuations in sheep blowflies by changing his
experimental conditions such that:��� |
D) both larvae and adults were provided a limited food supply.
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20. Which of the following processes contributes to the dynamics of metapopulations??od.
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A) growth and regulation of subpopulations within patches
B) colonization of empty patches to form new subpopulations Chapter 12: Temporal and Spatial Dynamics of Populations 5 C) extinction of established subpopulations D) all of the above 40 |
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21. What happens to a metapopulation when there is a high rate of migration between its
subpopulations? |
D) It behaves like a single large population.
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22. A metapopulation has an extinction rate, e, of 0.2 and a colonization rate, c, of 0.2. What is the
ultimate fate of this metapopulation, according to the basic model of metapopulation dynamics, p = 1 e/c?�/�N |
C) The entire metapopulation will go extinct.
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23. A metapopulation has an extinction rate, e, of 0.0 and a colonization rate, c, of 0.2. What is the
ultimate fate of this metapopulation, according to the basic model of metapopulation dynamics, p = 1 e/c?�/�N |
A) All patches will be occupied.
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24. A metapopulation has an extinction rate, e, of 0.1 and a colonization rate, c, of 0.2. What is the
ultimate fate of this metapopulation, according to the basic model of metapopulation dynamics, p = 1 e/c?�/�N |
B) There will be a shifting mosaic of occupied and unoccupied patches.l
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25. In a study of the butterfly Hesperia comma on patches of calcareous grassland in England, the
probability of patch occupancy was determined by: |
C) both patch area and patch isolation.�
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26. The rescue effect can:
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A) keep declining subpopulations from dwindling to small numbers and eventual extinction.
B) only work if there is some migration between subpopulations. C) increase the survival of subpopulations in the presence of large, productive neighboring subpopulations. D) all of the aboveped |
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27. How does a metapopulation model incorporating a rescue effect differ from a model without
one? |
A) The rate of extinction, e, decreases as the proportion of patches occupied increases.
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28. The 20 female adults in a small population each has a probability of 0.5 of producing a single
female offspring each year and a probability of 0.5 of producing no offspring. How many female offspring will be produced this year? |
B) any number of offspring from 0 to 20�
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29. In a simple case, one in which birth and death rates (b and d) are equal and the average change
in population size is zero, the probability of population extinction decreases with:be: |
A) increasing population sizeed.
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30. Are density�]independent stochastic models relevant to natural populations, given that birth and
death rates in these models do not change with respect to population density? �t� |
A) Yes
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1. A small population of wolves founded by a single breeding pair on the Scandinavian peninsula
in 1983 showed little vitality until 1991, when the population began to grow exponentially. What event in 1991 led to the increased vitality of the population?��Hw |
B) infusion of new genes into the pack by a single immigrant male
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2. Genetic analyses are finding new applications in ecology, leading to the understanding of the
geographic structure of natural populations, mating relationships, movements of individuals within populations, and histories of change in population size.on?��Hw |
A) True
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3. A given amino acid is encoded by only a single, unique base sequence in DNA.
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B) False
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4. A point mutation (substitution of a single nucleotide in a DNA codon) in a gene for a particular
protein always results in a change in the amino acid sequence in the corresponding protein. |
B) False
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5. Although there may be many different alleles of a particular gene in the gene pool for a
population, each diploid individual can only carry a small portion of that genetic variation.otein. |
A) True
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6. Microsatellites are tandem repeats of sequences of two, three, or four nucleotides in an
individual�s DNA. Although noncoding, these microsatellites are useful as |
C) genetic markers0beech
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7. Natural selection generally tends to reduce genetic variation. Which of the following can
maintain or even enhance the level of genetic variation present in a population? |
E) all of the abovebeech
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8. The probability that an individual complex organism (such as a vertebrate) is likely to sustain
one or more mutations in some part of its genome during its lifetime is:n? |
D) high.
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9. Although the human sickle�]cell gene causes debilitating anemia when expressed in homozygous
form, it persists at relatively high frequency in some African populations, because in heterozygous condition, the sickle�]cell allele confers an advantage. What is that advantage? |
A) protection against malariaed.
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10. The advantage to heterozygotes described in the previous question is an example ofs.
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E) frequency�]dependent selection to 20�
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11. The Hardy�]Weinberg law states that the frequencies of alleles and genotypes remain constant
from generation to generation in a population with |
A) a large (infinite) number of individuals
B) random mating C) no natural selection D) no mutation E) no migration between populations F) All of the above conditions must be met. |
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12. In a particular population, gene A has only two alleles, A1 and A2. The frequencies of these two
alleles are known and designated p and q, respectively. What would the equilibrium frequency of the genotype A1A2 be |
D) 2pq
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13. In a particular population, gene A has only two alleles, A1 and A2. The frequencies of these two
alleles are known and you calculate the Hardy�]Weinberg equilibrium frequencies of the three possible genotypes, A1A1, A1A2, and A2A2. The actual frequencies of these genotypes in the population depart substantially from the equilibrium frequencies. Which of the following processes is responsible for this departure from equilibrium frequencies?@� |
A) genetic drift D) natural selection
B) assortative mating E) any of the above, or some combination C) migrationled:D |
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14. Of the following, the Hardy�]Weinberg equilibrium is much more sensitive to departures from
one. Which is it?nled:D |
E) random mating
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15. Of the two kinds of assortative mating, one leads to a reduction in the proportion of
heterozygotes in a population. Which is it? |
A) positiveating
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16. Which of the following results in inbreeding?
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B) positive assortative matingd.
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17. You maintain two monkeyflower (Mimulus guttatus) populations, one with enforced selfing, the
other (control) where outcrossing is permitted. Which of the two populations exhibits consistently high ovule number and number of viable pollen grains per flower, generation after generation?$I |
B) outcrosseding
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18. When all alleles of a gene except one are lost from a population, we say that the remaining
allele is fixed. When fixation occurs, what is the value of the inbreeding coefficient (F)?ein. |
E) 1.0
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19. In studies of both song sparrows and wolves, researchers found the following relationship
between the survival of offspring and the inbreeding coefficient (F).as |
B) Survival decreased with increasing values of inbreeding coefficient.
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20. In experiments with the plant Banksia spinulosa, researchers in Australia showed that individual
plants: |
A) can make distinctions among developing embryos on the basis of their genotypes.e ofs.
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21. Genetic drift results from stochastic variation in birth and death rates, and it is thus most
important in __________ populations. |
A) small
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22. A small population of a sexually reproducing lizard has dwindled to two individuals, one male
and one female. Both are heterozygous (B1B2) for the gene B. These individuals mate and produce three offspring. The adults are then eaten by a bird. What is the probability that allele B2 has become fixed in the population, which now consists of the three offspring? |
A) 1/64
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23. A large "raft" of floating vegetation breaks loose from a tropical mainland area during a violent
hurricane. After days adrift, the raft reaches a small island. Among the animals on this raft are eight lizards belonging to a species not previously found on the island. Several years later, the population established by these individuals is studied carefully and found to have a __________ level of genetic variation compared to the parent (mainland) population from which the original eight colonists came.0�r |
C) substantially reduced
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24. Loss of genetic variability in a population following colonization or any other form of population
decline is referred to as aons.! |
D) population bottleneck
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25. Which of the following species of East African carnivores has been monitored closely by
conservationists after the discovery that this animal has practically no genetic variation? |
D) cheetah
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26. A population of an endangered plant is monitored over a period of 5 years. The following
population sizes are recorded: 30, 50, 30, 20, and 70. What is the effective population size (Ne)? |
C) less than 40
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27. Imbalance in the number of males and females contributing to future generations, as occurs in
many promiscuous mating systems, has which of the following effects on effective population size? |
B) no effect 40
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28. The example of the Galapagos tortoises presented in the text contrasted two medium�]sized
populations (100.600 tortoises) with a third, much larger, population (3,000.5,000 tortoises), all found on Isabela Island. The largest population has considerably lower variation in its mitochondrial haplotype, with most individuals representing a single haplotype. What did researchers conclude about this largest population? |
A) It was founded by one or a small number of individuals and recently grew to its present
large size.? |
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29. All the copies of a single gene in a population will have descended from a single copy that
existed at some time in the past. We refer to the elapsed time as the __________ time.? |
D) coalescence0
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30. The fact that within�]island genetic similarity among Galapagos hawks declines with increasing
island area is indicative of lower values of the equilibrium fixation index on larger islands, a reflection of:�/�N |
A) equilibria established between processes of genetic drift and mutation. DNA.
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31. As a rule of thumb, how many immigrants per generation would be sufficient to prevent genetic differentiation in a subpopulation with respect to genes that have no (neutral) effect on
fitness? |
B) 1
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32. Plants of yarrow, Achillea millefolium, grown from seed collected from various habitats ranging
from sea level to more than 3,000 meters in elevation, retained distinctive differences in plant size and other traits when grown in a common garden at sea level, indicating the existence of __________ variation. |
C) ecotypicnce0
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33. As illustrated in the research conducted by Price and Wasser on Delphinium nelsoni,
outbreeding is always desirable, even if matings occur between individuals separated by great distance. |
B) False
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34. Antonovics and Bradshaw discovered that plants of sweet vernal grass growing on mine tailings
in North Wales exhibited high zinc tolerance, despite the existence nearby of plants with relatively low zinc tolerance. They proposed that __________ for zinc tolerance on the mine tailings was sufficiently high to overcome gene flow from adjacent intolerant plants. |
B) selection pressure
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35. In the zinc�]tolerant subpopulation of sweet vernal grass discussed in the preceding question,
what was happening that would limit the flow of intolerant genes from the adjacent subpopulation on uncontaminated soils?) |
D) increased self�]compatibility
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1. Among the possible interactions between species, commensalism and amensalism are not
often considered in experimental and theoretical studies. Why? |
C) Such interactions lack a mutual dynamic between the two participants.
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2. Which of the following statements about parasites is incorrect?pants.
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A) A parasite may kill its host.
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3. Parasitoids resemble:
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A) parasites, in that they reside within and eat the tissues of a living host.
B) predators, in that they inevitably kill their hosts. C) both A) and B). |
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4. Which of the following does not directly affect the abundance of its food supply?ofs.
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E) detritivore0
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5. For which of the types of consumer listed below would we be least likely to refer to its food
source as a "host"?d:D |
E) detritivore0
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6. Which of the following feeds on living woody vegetation?ly.
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B) browser
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7. Of the following kinds of consumers, which is involved in a close association with its resource
and is highly likely to cause its death? |
D) parasitoids0
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8. Of the following kinds of consumers, which is involved in a casual association with its resource
and is unlikely to cause its death? |
A) grazers and browsers:
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9. In experiments with bullfrog tadpoles, Relyea and Werner showed that, in comparison to
predator�]free controls, tadpoles exposed to caged predators: |
D) were less active and grew more slowly.nct.
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10. The symbiotic bacterium, Wolbachia, infects a variety of different insect hosts. Which of the
following is true of Wolbachia?death? |
C) Its most significant effects result from modification of sexual function.NA.
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11. Some mutualistic relationships may have evolved from host�]parasite interactions.fs.
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A) True
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12. The malarial parasite, Plasmodium, undergoes a complex life cycle in which asexual
reproduction occurs in ___________ and dispersal and sexual reproduction occur in __________..? |
A) a vertebrate host; a mosquito
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13. A vertebrate host infected with the malarial parasite, Plasmodium, typically reacts with an
inflammation (high fever) when: |
D) merozoites are released into the bloodstream.
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14. Which of the following is utilized by parasites to circumvent the host�s immune system?).r��
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A) production of chemical factors that suppress the immune system
B) production of surface proteins that mimic the host�s own proteins C) continuous production of novel surface proteins D) coating themselves with the host�s proteins E) all of the above?��Hw |
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15. Which of the following is utilized by schistosome species to circumvent the host�s immune
system?.? |
D) coating themselves with the host�s proteinsm.
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16. When a vertebrate host mounts an immune response to a parasite closely related to another
parasite that previously infected the same host, we refer to this phenomenon as __________.tionn. |
B) cross�]resistanceers:
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17. Compounds produced by plants for purposes other than metabolism, chiefly defense, are
referred to as __________ compounds.: |
B) secondaryds0
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18. Plants produce tannins as defensive compounds that deter herbivory. Tannins reduce the
digestibility of plant material in a:?death? |
B) reaction binding proteins of all types.einsm.
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19. Tannins (previous question) are produced at relatively high levels in leaves of oaks and other
plants, whether or not the plants have been browsed by herbivores. This is an example of a(n) __________ defense.�N |
A) constitutive
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20. Essential oils, latex, and resins fall into the broad group of plant antiherbivore defenses known
as:?s: |
B) terpenoidsve
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21. Alkaloids, which include morphine, atropine, and nicotine, are plant antiherbivore defenses
having well�]known effects on the central nervous system of vertebrates, including humans. To which of the three broad groups of plant antiherbivore defenses do alkaloids belong?e? |
A) nitrogen compoundsrs:
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22. When shoots of aspen, poplar, birch, and alder are heavily browsed by snowshoe hares, shoots
produced during the following growing season have exceptionally high concentrations of terpenes and phenolic resins, which are extremely unpalatable to hares. This is an example of a(n) __________ defense. |
B) induced
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23. Two predators consume the same prey species. Because each predator reduces the availability
of this prey organism for the other, we can refer to the interaction between the two predators as one involving __________.?) |
A) competitione
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24. A seedling of a saguaro cactus benefits from shade against the sun and protection from
herbivores afforded by small trees (such as ironwood and palo verde) that serve as nurse plants. When the saguaro is small the relationship between the saguaro and its nurse plants is an example of __________. |
E) commensalism
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25. A seedling of a saguaro cactus benefits from shade against the sun and protection from
herbivores afforded by small trees (such as ironwood and palo verde) that serve as nurse plants. When the saguaro grows to maturity the relationship between the saguaro and its nurse plants is an example of __________. |
A) competitionm
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26. The early relationship between pioneer plants and the later successional plants that replace
them is often an example of facilitation. However, once the later successional plants become well established, the relationship between pioneers and these later successional species is an example of __________._. |
A) competitionm
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27. Rhizobium bacteria and roots of legumes form mutualistic partnerships that would be classified
as __________.t"?d:D |
A) trophictionm
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28. The kind of mutualism studied by Daniel Janzen between Acacia plants and Pseudomyrmex ants
would be classified as __________.death? |
B) defensiveonm
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29. Based on your knowledge of the three general categories of mutualism, choose from the
following list the order that ranks these from less restrictive to more restrictive. (Hint: By restrictive, we mean a relationship that involves specialization on the parts of the participants.)le |
C) dispersive, defensive, trophic to 20�
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30. Among dispersive mutualisms, which of the following tends to be more restrictive?fs.
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B) plant�]pollinator mutualismso
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1. If you were searching for a predator ideally suited to controlling a particular insect species that
damages crops (such as cyclamen mites on strawberries), which of the following predator attributes would you seek? (Assume that the predator does, in fact, eat the insect species in question.) |
A) high reproductive capacity compared to that of the prey
B) strong dispersal powers C) ability to switch to alternative food resources when the primary prey are unavailable D) all of the above |
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2. When the predator of the cyclamen mite was controlled through application of the insecticide
parathion to strawberry plants in the greenhouse, what happened to the population of the cyclamen mite? |
A) The population of the cyclamen mite grew rapidly to a damaging level.
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3. The effort to control the Klamath weed by introduced beetles in the genus Chrysolina illustrates
which of the following?ds.: |
A) Herbivores can have substantial effects on the performance of plant populations.e?fs.
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4. In Canada, most large herbivorous prey (snowshoe hares, muskrat, ruffed grouse, and
ptarmigan) have population cycles with periods of:h? |
A) 9�]10 yearsm
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5. In which of the following habitats in Canada are predator�]prey population cycles observed to
have longer periods?:D |
B) forestyearsm
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6. In Canada, most predators have population cycles that:n?ly.
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B) have the same periodicity as those of their prey species.y.
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7. In general, population models predict that the period of a population cycle will be about how
many times as long as the lag in response to a change in the environment?:n? |
B) 4�]5
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8. Pathogens infect individuals more readily in crowded than in sparse populations because the
chances of contacting a new host are greater in a crowded population.s |
A) True
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9. Nuclear polyhedrosis virus, which causes high mortality in the forest tent caterpillar, was found
to exert less influence on caterpillars in fragmented forests because:n? |
C) more intense sunlight inactivates the virus..
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10. When G. F. Gause placed Paramecium, a prey species, and Didinium, a predator species,
together in plain test tubes with a nutritive medium: |
A) the prey were driven to extinction by the predator, which then starved.n.NA.
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11. When G. F. Gause placed Paramecium, a prey species, and Didinium, a predator species,
together in test tubes with a nutritive medium and a glass wool refugium for the prey:____..? |
B) the predator went extinct after consuming some prey, leaving the remaining prey to
flourish. |
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12. G. F. Gause was able to maintain oscillating populations of Paramecium, a prey species, and
Didinium, a predator species, together in test tubes by:). |
D) periodically adding small numbers of predators.y.
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13. One of the most elaborate laboratory experiments devoted to coexistence of predator and prey
was conducted by C. B. Huffaker. His experiments focused on __________.se:n? |
D) six�]spotted mites and their predator, Typhlodromus
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14. What was a key finding emerging from the laboratory studies conducted by C. B. Huffaker?ish.
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D) Predator and prey coexist only within a spatial mosaic of suitable habitats.
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15. In Huffaker�s experiments with coexistence of predator and prey, a tenuous coexistence was
achieved only when the following condition was met:tors: |
A) time delay resulting from slow dispersal of predators
B) time delay resulting from slow predator response to increased prey abundance C) presence of suitable refuges for prey D) all of the above |
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16. In the Lotka�]Volterra population model for a prey population, dV/dt = rV �] cVP, which of the
terms on the right�]hand side of the equation incorporates dependence on predator abundance?e above |
B) cVPw
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17. In the Lotka�]Volterra population model for a prey population, dV/dt = rV �] cVP, which of the
terms on the right�]hand side of the equation reflects exponential growth of the prey population in the absence of predators?� |
A) rVHw
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18. In the Lotka�]Volterra population model for a prey population, which of the following processes
is affected by predators?.: |
B) deaths
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19. In the Lotka�]Volterra population model for a predator population, dP/dt = acVP �] dP, which of
the terms on the right�]hand side of the equation incorporates dependence on prey abundance?e above |
A) acVP
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20. In the Lotka�]Volterra population model for a predator population, dP/dt = acVP �] dP, which of
the terms on the right�]hand side of the equation reflects the probability of predator death regardless of the size of the prey population?ll of t |
B) dPHw
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21. In the Lotka�]Volterra population model for a predator population, which of the following
processes is affected by prey??.: |
A) birthsyearsm
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22. How would you characterize the Lotka�]Volterra predator�]prey model of population dynamics?.
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B) continuous�]timedsrs:
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23. In the Lotka�]Volterra population model for predator and prey populations, what happens when
a system with populations at the joint equilibrium is moved away from this equilibrium?.tionn. |
C) The system begins cyclic oscillations.virus..
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24. Given the behavior addressed in the previous question, what property would you ascribe to the
Lotka�]Volterra model?rey??.: |
B) neutral stabilitysrs:
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25. Brendan Bohannon and Richard Lenski tested the predictions of the Lotka�]Volterra predatorprey
model in a simple microcosm experiment. What was their general conclusion? |
B) The Lotka�]Volterra model captures the essence of predator�]prey interactions.s.e?fs.
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26. In the Bohannon/Lenski microcosm experiment (previous question), the prey item was a
bacterium, Escherichia coli. What was the predator?um: |
D) the bacteriophage, T4
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27. In the S�]I�]R model of disease transmission, what value of R0 will result in a disease epidemic
when a small number of infectious individuals are introduced into the population?? |
D) R0 > 1yearsm
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28. In the S�]I�]R model of disease transmission, what is the eventual outcome when an epidemic
spreads through a host population?eath? |
D) The epidemic runs its course.
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29. Recent experience with the chytrid fungus and global decline of amphibians is that a multi�]host
pathogen has the ability to persist and spread even after driving one of its hosts extinct.e above |
A) True
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30. The ultimate fate of predators and prey that conform to the Lotka�]Volterra model is that
random perturbations will eventually increase oscillations in population size to the point where one or both of the populations will die out.ion |
A) True
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31. Individual Zyngis, insatiable predators, consume prey in direct proportion to their abundance or
density at rate c. What kind of functional response do Zyngis have (using the categories devised by C. S. Holling)?__.?) |
A) type Iyearsm
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32. Is the functional response of Zyngis (previous question) consistent with the basic model of
predator�]prey population dynamics developed by Lotka and Volterra?.s |
A) Yesw
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33. Holling type II and type III functional responses differ little at high prey densities. Both exhibit::?s:
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A) a leveling�]off in consumption rates of individual predators at high prey densities..
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34. What separates the Holling type II and III functional responses?vel.
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A) In the type III response, the proportion of prey consumed per predator is decreased at
lower prey densities. |
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35. A Holling type III functional response might be the result of which of the following?amics?.
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A) heterogeneous habitat
B) lack of reinforcement of learned searching behavior C) ability of the predator to switch to alternative prey D) all of the aboveD |
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36. Many species of predator exhibit relatively slow population growth, yet in some cases their
numerical response to increased prey density can be relatively rapid. What process could contribute to this rapid numerical response? |
A) immigration of individuals from surrounding areasus
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37. When predators and their prey exhibit cyclic population oscillations, the typical pattern is for:?.?
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A) numerical response of the predator to lag behind that of the prey.el.
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38. Only one of the following factors tends to destabilize a predator�]prey relationship, leading to
greater amplitude of cyclic population fluctuations. Which is it? |
D) time delays in the responses of populations to changes in their food supplies
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39. Which of the following factors can balance destabilizing forces and constrain the amplitude of
predator�]prey cycles?ey??.: |
A) predator inefficiency
B) density�]dependent limitation of predator or prey by external factors C) alternative food sources for the predator D) safe refuges from predation at low prey densities E) reduced time delays in predator responses to prey abundance F) all of the above in |
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40. The lesson for biological control of pest populations from modeling efforts is as follows: When a
prey species escapes from control by its predator, it can be readily brought back to a low equilibrium density by renewed attention from its predator. |
B) False
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1. Tansley's early research on competition was groundbreaking because:l.
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D) he was the first to test experimentally the idea that competition could determine the
distribution of species.ods?:D |
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2. Which of the following did Tansley determine from his research on species in the plant genus
Galium? |
A) The presence or absence of a species could be determined by competition with other
species. B) The conditions of the environment affect the outcome of competition. C) The present ecological segregation of species may reflect past competition. D) all of the abovebelong?e? |
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3. Individuals belonging to the same species cannot compete because cooperative and altruistic
relationships among the individuals promote the betterment of the species.ion? |
B) False
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4. The resource requirements of two plant species, A and B, have been carefully studied.
Researchers have determined the levels of a particular resource required by both species that will support equilibrium levels of each species. The level of this resource required to maintain the equilibrium level of species A is higher than that required to maintain the equilibrium level of species B. When these two species are placed in competition (under conditions in which this resource is limiting), which of the two species is likely to displace the other? |
B) species Brsm
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5. Which of the following does ecologist David Tilman consider the attribute(s) of a resource??.
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A) A resource is consumed, and its amount or availability is thereby reduced.
B) A resource is used by a consumer for its maintenance and growth C) Reduction of a resource's availability leads to reduced population growth of a consumer. D) all of the above |
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6. Which of the following is not a resource for terrestrial plants?se:l.
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D) temperaturem
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7. Which of the following is not a renewable resource for a species of predatory bird?..
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D) nest sitesem
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8. Ecologists recognize three types of renewable resources, listed below. Consider the process
whereby nitrogen taken up by plants is recycled (through decomposition of plant remains) and made available for subsequent consumption by other plants. In this context, which of the three resource types is soil available nitrogen (as nitrate, for example)?it? |
C) a resource whose abundance is indirectly linked to uptake by consumersupplies
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9. The competitive exclusion principle was based on which of the following research findings???.
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A) Competing species do not coexist indefinitely when sharing the same limiting resource in
laboratory experiments.s?:D |
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10. The mathematical models for competition between species are based on which of the
following?Galium? |
C) logistic population growth equation0�
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11. In the competition equations developed by Lotka and others, what does the term a1,2N2ngs???. represent
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D) reduction of species 1's carrying capacity by individuals of species 2upplies
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12. Which of the following make(s) coexistence of species 1 and 2 more likely?es
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D) lower values of both a1,2 and a2,1n0�
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13. Which of the following statements best expresses the condition for coexistence of two species,
according to the competition models developed by Lotka and others?? |
A) To coexist, species must limit themselves more than they limit each other.?es
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14. When David Tilman grew diatoms in the genera Cyclotella and Asterionella at Si/P ratios
between 6 and 90, the two species coexisted. Why?m: |
D) One species was limited by phosphorus, and the other was limited by silicon.s
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15. In David Tilman�s experiments with diatoms in the genera Cyclotella and Asterionella, he found
that Cyclotella was equally limited by silicon and phosphorus at a ratio of Si/P = 6, and that Asterionella was equally limited by the two elements at a ratio of Si/P = 90. When he grew the two species at a Si/P ratio exceeding 90 (455 in his experiment), which species excluded the other? |
B) Asterionella
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16. In David Tilman�s experiments with diatoms in the genera Cyclotella and Asterionella, he found
that Cyclotella was equally limited by silicon and phosphorus at a ratio of Si/P = 6, and that Asterionella was equally limited by the two elements at a ratio of Si/P = 90. When he grew the two species at a Si/P ratio below 6 (0.6 in his experiment), which species excluded the other?other? |
A) Cyclotellala
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17. Which of the following is a limiting resource for barnacles growing on rocky intertidal areas?alium?
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D) space
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18. Which of the following experimental approaches did Joseph Connell use to determine the
cause(s) of vertical zonation in two species of barnacles along the Scottish coast? |
D) removal of one or the other of the species of barnacless.y.
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19. In the rocky intertidal zone of the Scottish coast, which factors were found to control the
vertical zonation of barnacles? |
A) competition
B) differential tolerance of stressful conditionss?se:l. |
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20. In the lower rocky intertidal zone of the Scottish coast, the barnacle Balanus is a much more
effective competitor than the barnacle Chthamalus. What aspect of competition does this situation illustrate?ense.�N |
B) asymmetryala
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21. According to P. J. Grubb and David Tilman, plants compete __________ intensely when mineral
elements are less abundant in the soil. |
A) more
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22. Based on the results of various competition experiments reviewed in Chapter 16, what can we
conclude about our ability to predict the outcome of competition?ers?? |
B) Competition appears to be pervasive, but how it is manifested depends very much on the
characteristics of the interacting species and their habitats. aboveD |
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23. Anyone watching a hummingbird feeder has observed that individual hummingbirds will chase
away other hummingbirds, as well as insects, that attempt to visit the feeder. Such encounters are examples of: |
A) interference competitionurse.
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24. A group of children at a birthday party sit around a table covered with pieces of candy. Each
child must gather candy, one piece at a time, as fast as possible. No child is permitted to impede the access of another child to the remaining candy on the table. When the table has been cleared, the child with the most pieces of candy is declared the winner. This is an example of:?other? |
B) exploitative competitionurse.
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25. Where shrubs (such as Salvia) and grassland meet in dry areas in southern California, there is
often a few feet of bare ground separating the two. Which of the following mechanisms has been proposed to explain this observation?on from |
B) allelopathic inhibition of grasses by shrubs.
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26. What additional factor (beyond that referenced in the previous question) appears to play a role
in maintaining the bare areas between shrubs and other plants in dry areas in southern California? |
B) selective herbivory by rabbitsa
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27. One of the first scientists to recognize that grazing can maintain a high diversity of potentially
competing species in grasslands was __________.: |
D) Charles Darwin
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28. In his study of invertebrate animal communities on rocky intertidal areas in the state of
Washington, Robert Paine found that removal of a predator (Pisaster, the sea star) led to __________ in community diversity..?) |
C) a decrease
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29. Peter Morin of Rutgers University stocked artificial ponds with tadpoles of toads in the genera
Scaphiopus (spadefoot toad) and Bufo (southern toad) and a frog, Hyla (spring peeper). What was the outcome of competition among these three species in the absence of predation? (Hint: Refer to Figure 16.18.). |
C) spring peepers were nearly eliminated
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30. In Peter Morin's study of coexistence among toad and frog tadpoles, presence in ponds of a
predatory newt at high levels (eight individuals) resulted in: (Hint: Refer to Figure 16.18.)nn. |
B) enhanced survival of the frog (Hyla)d
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31. What was the principal finding from Peter Morin's study of coexistence among toad and frog
tadpoles?e above |
C) Predation can reverse the outcome of competition among prey species..
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32. What causes the negative effect on some species of coral when certain algae are growing in the
vicinity?ove |
C) The algae produce polysaccharides, which stimulate microbial growth, which in turn
consume oxygen, limiting the growth of the corals. Why?m: |
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33. In the coral reef experiment referred to in the previous question, what treatment did
researchers apply to the system?cles? |
C) antibiotic
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34. Two closely related species of fish occupy a 100�]km section of a river. The temperature of this
section of the river increases gradually from 5��C upstream to 10��C downstream. One species (fish A) is found in the cooler, upper 50 km of the stream and the other species (fish B) is found in the warmer, lower 50 km of the stream. There is no overlap in the distributions of fishes A and B. Why do these two species have nonoverlapping distributions? |
C) It is impossible to answer this question without conducting experimental studies of this
system.ium? |
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1. Initially devastating to Australian rabbits, myxoma virus became less lethal within a few years of
its introduction as a biological control agent. Why?boveD |
A) evolution of resistance on the part of rabbits
B) evolution of reduced virulence on the part of the virus C) both of the abovesoil. |
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2. Coevolution, by definition, cannot occur between a biological population and an abiotic factor.m.ium?
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A) True
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3. Which of the following situations is most likely to meet the requirements of a strict definition of
coevolution?s?:D |
D) the ability of an insect herbivore to detoxify antiherbivore substances produced by its host
plantm? |
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4. Which of the following antipredator defenses is more likely to be found in an animal that is
palatable to its predators?les? |
A) crypsistic
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5. Aposematic animals have conspicuous markings and bright colors, which serve as warnings to
would�]be predators. You find a brightlycolored butterfly that is unknown to you. Can you safely conclude that this butterfly is distasteful to predators? |
B) No, some conspicuously marked animals are palatable to predators.es..
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6. Which of the following biologists has been honored by having his name associated with a type
of mimicry in which a palatable model mimics an unpalatable model?rs?? |
D) Henry Bates
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7. When one prey species mimics another unpalatable prey species (the model) to reduce its own
risk of predation, the mimic is always palatable to predators.eD |
B) False
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8. When one prey species mimics another unpalatable prey species (the model) to reduce its own
risk of predation, the mimic is always a close relative of the model.?? |
B) False
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9. The evolutionary biologist Charles Mode proposed a model of host�]pathogen evolution that
predicted cyclic change in frequencies of host resistance and pathogen virulence through time. Which of the following was a key element in Mode's model?r |
A) control of virulence and resistance by single dominant genes
B) costs associated with virulence and resistance, by themselves, to host and pathogen, respectively C) fitness of host or pathogen contingent on the genotype of the other D) all of the aboveX� |
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10. What kind of approach did Ehrlich and Raven take in their research on coevolution, published in
1964?ty?ove |
A) recording repeating patterns in nature and inferring from these coevolutionary
relationships |
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11. David Pimentel established an experimental population of houseflies from stock that had a long
history of prior experience with a parasitoid wasp. He also introduced parasitoid wasps into this population and observed the change in numbers of the two species through time. The flies in this experiment:8.). |
C) exhibited a stable and relatively high constant population level.es..
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12. In Pimentel�s experiments with houseflies and their parasitoids (see previous question), he
created two treatments. In one treatment, the host population (houseflies) was not permitted to evolve responses to the parasitoid, whereas evolution of host responses was permitted in the other treatment. What happened to the parasitoid population in the treatment in which host evolution was permitted? |
B) The parasitoid population exhibited reduced fecundity and shorter life span.s
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13. Which of the following statements correctly characterizes the status of pathogen resistance in
cultivated crops, such as wheat?oil. |
A) The system is in constant flux, as new virulent strains of pathogens appear and crop
breeders select resistant strains of the crop.. |
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14. The rust�]wheat system has an essential element of coevolution envisioned by Charles Mode.
What is it?y?ove |
B) There is an interaction between the fitnesses of the genotypes of the host and the
genotypes of the pathogen.on?s?:D |
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15. As illustrated in the simple model of Figure 17.12, the balancing influences of consumer and
resource adaptation can achieve an evolutionary equilibrium. What is happening at this point?. |
B) Both consumer and resource continue to evolve to maintain this equilibrium..s
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16. Which hypothesis, introduced in Chapter 8 as part of the discussion of sexual reproduction,
applies well to the evolutionary equilibrium illustrated in Figure 17.12?oast? |
A) the "Red Queen" hypothesisse.
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17. When consumer and resource populations in evolutionary equilibrium (see Figure 17.12)
experience a sudden environmental change that leads to a much higher rate of exploitation, which population is likely to experience greater selective pressure and thus exhibit the greater rate of evolutionary change?.). |
B) the resource
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18. In studies conducted by David Pimentel and colleagues, houseflies and blowflies were grown
together in an experimental cage that permitted long�]term coexistence of the two species. During one 70�]week study, blowflies remained at low levels throughout most of the experiment, but, at about 50 weeks, they showed a dramatic population increase, at the expense of the houseflies. The evolution of superior competitive ability by a rare competitor is an example of what kind of selection? |
A) frequency�]dependent4
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19. Two species of grain beetles (identified only as 1 and 2) are collected in the field and
maintained under laboratory conditions for 1 year, encompassing many generations. Some of the grain beetles are maintained in pure culture (P1 and P2) and others in mixed culture (M1 and M2), all under conditions of limiting food resources. At the end of the year, grain beetles of species 1 from the mixed culture are tested for their competitive ability against the other species from pure culture (M1 �] P2). A similar test is conducted, pitting grain beetles of species 1 from pure culture against the other species from pure culture (P1 �] P2). In which case would you expect species 1 to show greater competitive ability with species 2?z� |
A) M1 �] P2urce
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20. Character displacement:isse.
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C) can be identified by comparing populations in allopatry and sympatry.
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21. Related species that live together typically differ in the way they use resources. This is evidence
that these differences have evolved as a result of competitive interactions.n?? |
B) False
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22. Species 1 occurs in areas A and B, and its close relative, species 2, occurs in areas B and C.
Areas A, B, and C all have similar environmental conditions and habitats. Which of the following might we reasonably expect?ponse? |
B) The sympatric populations of species 1 and 2 in area B will differ more from each other than
the allopatric populations of these two species in areas A and C.el.?? |
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23. The ground finch genus Geospiza consists of several species distributed haphazardly across the
Galapagos Islands. When two or more Geospiza species occur on the same island, the beak size ranges for these species:..?) |
C) exhibit no overlap.t4
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24. Geospiza fuliginosa occurs in isolation on Daphne Island and G. fortis occurs in isolation on Los
Hermanos Island in the Galapagos. Their bill size ranges overlap considerably (refer to Figure 17.17). In 1925, an overzealous tourist captured several individuals from each population and successfully established these on nearby Cocos Island, where ground finches did not occur. In a recent survey, you measured bill sizes from a large sample of both species on Cocos Island. What did you find? |
B) The two species had diverged somewhat in their bill size ranges.atry.
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25. A well�]studied mutualism involves ants, aphids, and leafhoppers. The ants protect the aphids
and leafhoppers from predators and are rewarded with the nutritious honeydew secreted by these insects. What can we conclude from this mutualism?l o |
A) A mutualism with this degree of specificity appears to represent coevolution.
B) A mutualism with this degree of specificity does not appear to represent coevolution. C) We have insufficient evidence to conclude either A or B. |
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26. The tropical leguminous tree, Dioclea macrocarpa, produces L�]canavanine, an amino acid that is
toxic to most insects. D. macrocarpa lacks close relatives that produce this amino acid. A bruchid beetle, Caryedes brasiliensis, has enzymes that enable it to feed on D. macrocarpa. C. brasiliensis lacks close relatives that produce these enzymes.What can we conclude from this mutualism? |
A) A mutualism with this degree of specificity appears to represent coevolution.
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27. Why do plants having strong chemical defenses against herbivores, such as angular
furanocoumarins (AFCs), sometimes suffer high levels of insect herbivory? |
C) Some insect herbivores can tolerate these defenses and can feed freely on the plants.
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28. In May Berenbaum's studies of the coevolution of plants in the parsley family (Umbelliferae) characterized as:rlap.t4
and their insect herbivores, groups of plant species that evolved more recently were?? |
D) less diverse and having more toxic chemical defenses against herbivores.tion.
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29. Insects feeding on umbelliferous plants containing the highly toxic angular fumarocoumarins
(AFCs): |
A) had close relatives feeding on other umbelliferous plants containing similar but less toxic
chemical defenses.n?s?:D |
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30. The branch of evolutionary biology that uses similarities and differences among species to
determine their evolutionary relationships is known as:: |
D) phylogenetic reconstructione.
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31. In the yucca�]moth mutualism, the moth, Tegeticula, is the sole pollinator of the yucca, and the
yucca is the sole food source for the moth. Because of the tight and obligate relationship between these two species, we would refer to this mutualism as a _________b |
E) symbiosisrce
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32. What adaptations on the part of yucca moths support their tight and obligate mutualistic
association with yuccas?:D |
A) Individuals visit flowers of only a single species of yucca.
B) Mating occurs within the flowers. C) Females lay their eggs within the ovary of the yucca flower. D) Females have specially modified mouthparts that enable them to gather and transport pollen. E) all of the abovein |
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33. In the yucca�]moth mutualism, female Tegeticula moths exercise restraint, laying so few eggs ina yucca ovary that the resulting larvae will consume no more than about 30% of the seeds in a
developing fruit. Imagine that a "cheater" moth genotype arose, one that laid sufficient eggs to consume all the seeds in a yucca fruit. Why would the fitness of this "cheater" genotype, which could potentially produce more offspring per visit to a yucca flower, be lower than that of the typical genotype? |
B) because yuccas abort developing fruits that contain sufficient larvae to consume the
majority of seeds?y?ove |
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34. Although the yucca�]moth mutualism appears to be highly coevolved, what appear to be
coevolved traits may have been preadaptations that were critical to the establishment of the obligate mutualism in the first place.) |
A) True
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35. Evolutionary biologists have coined the term __________ for situations in which populations
simultaneously respond to an array of complex interactions with many other species.re?? |
C) diffuse coevolutiont4
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36. Interactions among species are major sources of selection and evolutionary response.
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A) True
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1. Which of the following concepts of community organization suggests that a community is much
more than the sum of its individual parts?Why?m: |
A) holistic conceptiont4
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2. Which of the following concepts of community organization suggests that a community is
merely a fortuitous association of species whose adaptations and requirements enable them to live together under the physical and biological conditions of a particular place?__b |
B) individualistic concepttione.
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3. Identify the following statement with one of the following concepts of community organization:
"Each population within a community responds to evolutionary pressures with adaptations that maximize the reproductive success of its individual members, regardless of any benefits to the community as a whole.". |
B) individualistic concepttione.
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4. Many European ecologists use a complex taxonomy of communities, based on a rigidly defined
method of sampling plant species composition, which places each community in a hierarchy of types organized by their similarity. After whom is this system named? |
D) J. Braun�]Blanquetnt4
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5. As discussed in the previous question, much effort has been devoted to classification of natural
communities, and this effort continues today. Which American ecologist would have found the "pigeonholing" of natural communities into discrete classes most satisfying from a philosophical perspective? |
C) F. E. Clementsquetnt4
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6. Which of the following correctly pairs related concepts?.y.
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B) holistic concept, closed community
C) individualistic concept, open communitysponse. |
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7. Which of the following factors exhibits one of the most striking changes as one crosses the
ecotone between communities on serpentine and nonserpentine soils in southwestern Oregon?oint?. |
C) soil chromium
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12. Which of the following factors may be directly responsible for maintaining a sharp edge
between prairies and forests in the midwestern United States?ivory? |
D) fire
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13. The broadleaved deciduous forests of eastern North America contain many species of trees.
Which of the following statements best describes the geographic distributions of these species??. |
C) Each species has a different geographic range, but these ranges overlap to some extent.nships
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14. The tendency of certain forest species to occur in certain habitats (ridge tops or moist river
bottoms, for example) is convincing evidence for the closed community concept.s.re?? |
B) False
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15. An animal ecologist interested in gradient analysis would:
|
A) measure the abundance of animal species and physical conditions at a number of locations
and then plot the abundance of each species as a function of one or more physical conditions.es??. |
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16. Robert H. Whittaker, in a study of plant distributions in Great Smoky Mountains National Park,
provided considerable support for:.. |
A) the concept of open communitiesHyla)d
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17. Under which conditions in Great Smoky Mountains National Park would you seek communities
containing red oak, white oak, and beech? Refer to Figure 18.8.ry? |
D) high elevation, dryt4
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18. Biologists have catalogued all the species on earth, except for a few rare species in remote
tropical areas.ccas?:D |
B) False
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19. You are walking through a forest, and you soon discover that every other individual tree
belongs to a different species. Based on this fact alone, in which of the following countries are you likely to be walking?ace.) |
A) Ecuadorromium
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20. You have been maintaining a list of the bird species that frequent your property. At the end of
the year you have tallied eight seed eaters, one nectar sipper, three woodpeckers, six insectivores, two frugivores, four predators, and one carrion feeder. Which term best describes each of the categories you have used in your tally? |
B) guild
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21. Which of the following food web properties is independent of the species richness of the
community? |
A) number of feeding links per species)d
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22. Robert Paine conducted studies of rocky intertidal communities on the coast of Washington
and in the Gulf of California. Paine showed that removal of __________ consumers could result in reduction of the number of their resource species. syst |
C) both predator and herbivoree.
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23. In the construction of food webs, much information can be obtained through simple
observation of feeding relationships within communities. Which of the following types of food web could you construct from such observations, without further measurement or experimentation? |
A) connectedness webryt4
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24. Constructing which of the following types of food web would require an experimental
approachmunity? |
C) functional webwebryt4
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25. In a microcosm experiment, Chris Steiner and colleagues showed that resilience was positively
related to the number of species present, but only in __________�]productivity microcosmss??. |
A) loww
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26. When Hairston, Smith, and Slobodkin suggested that the earth is green because carnivores
depress the populations of herbivores that would otherwise consume most vegetation, they were focusing on __________ control of community structure. syst |
A) top�]downmium
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27. Hairston, Smith, and Slobodkin suggested that the earth is green because carnivores depress
the populations of herbivores that would otherwise consume most vegetation. Is this the only possible explanation for the "earth is green" phenomenon? |
B) No, perhaps the earth is green because most plants resist consumption through various
deterrents to herbivoryccas?:D |
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28. In a study conducted by Matthew Liebold and colleagues, the abundance of zooplankton was
positively correlated with the abundance of phytoplankton across a large number of natural lakes, indicating __________ control by plant production of the abundance of organisms feeding at higher trophic levels in aquatic systems yo |
B) bottom�]upium
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29. In the study referred to in the previous question, Matthew Leibold and colleagues added
predatory fish to experimental lakes. When fish were added, the abundance of zooplankton decreased, and the abundance of phytoplankton increased, indicating __________ control by predators of the abundance of organisms feeding at lower trophic levels in aquatic systems.ts. |
A) top�]downpium
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30. In a study of ponds and nearby terrestrial ecosystems, Tiffany Knight and colleagues showed
that the presence of fish in ponds had indirect, positive effects on the seed set of terrestrial plants. In particular, fish exerted this influence through their direct, negative effects on which organisms?hole.". |
A) larval dragonfliesyt4
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