Name: 
 

Unit 11 Ecology


Multiple Choice
Identify the choice that best completes the statement or answers the question.
 

 1. 
"How does the foraging of animals on tree seeds affect the distribution and abundance of the trees?" This question
a.
is a valid ecological question.
b.
is difficult to answer because a large experimental area would be required.
c.
is difficult to answer because a long-term experiment would be required.
d.
A and B only
e.
A, B, and C are correct.
 

 2. 
Which of the following levels of organization is arranged in the correct sequence from most to least inclusive?
a.
community, ecosystem, individual, population
b.
ecosystem, community, population, individual
c.
population, ecosystem, individual, community
d.
individual, population, community, ecosystem
e.
individual, community, population, ecosystem
 

 3. 
Ecology as a discipline directly deals with all of the following levels of biological organization except
a.
population.
b.
cellular.
c.
organismal.
d.
ecosystem.
e.
community.
 

 4. 
You are working for the Environmental Protection Agency and researching the effect of a potentially toxic chemical in drinking water. There is no documented scientific evidence showing that the chemical is toxic, but many suspect it to be a health hazard. Using the precautionary principle, what would be a reasonable environmental policy?
a.
Establish no regulations until there are conclusive scientific studies.
b.
Set the acceptable levels of the chemical conservatively low, and keep them there unless future studies show that they can be safely raised.
c.
Set the acceptable levels at the highest levels encountered, and keep them there unless future studies demonstrate negative health effects.
d.
Caution individuals to use their own judgment in deciding whether to drink water from a potentially contaminated area.
e.
Establish a contingency fund to handle insurance claims in the event that the chemical turns out to produce negative health effects.
 

 5. 
Species transplants are one direct way of
a.
determining the abundance of a species in a specified area.
b.
determining the distribution of a species in a specified area.
c.
developing mathematical models for distribution and abundance of organisms.
d.
determining if dispersal is a key factor in limiting distribution of organisms.
e.
consolidating a landscape into a single ecosystem.
 

 6. 
Introduced species
a.
often fail to colonize the new area.
b.
may become common enough to become pests.
c.
can disrupt the balance of the natural species with which they become associated.
d.
B and C only
e.
A, B, and C are all correct.
 

 7. 
Which of the following abiotic factors has the greatest influence on the metabolic rates of plants and animals?
a.
water
b.
wind
c.
temperature
d.
rocks and soil
e.
disturbances
 

 8. 
Which of the following statements about light in aquatic environments is (are) correct?
a.
Water selectively reflects and absorbs certain wavelengths of light.
b.
Photosynthetic organisms that live in deep water probably use red light.
c.
Light intensity is an important abiotic factor in limiting the distribution of photosynthetic organisms.
d.
A and C only
e.
A, B, and C are correct.
 

 9. 
Westerly winds in temperate zones are the result of
a.
descending air masses flowing toward the poles.
b.
the rotation of Earth.
c.
the unequal speed of land moving through space at the equator and the poles.
d.
A and B only
e.
A, B, and C
 

 10. 
In mountainous areas of western North America, north-facing slopes (compared with south-facing slopes) would be expected to
a.
receive more sunlight.
b.
be warmer and drier.
c.
support biological communities similar to those found at lower elevations and higher latitudes.
d.
support biological communities similar to those found at higher elevations and higher latitudes.
e.
B and C only
 

 11. 
Coral reefs can be found on the southern east coast of the United States but not at similar latitudes on the southern west coast. Differences in which of the following most likely account for this?
a.
sunlight
b.
precipitation
c.
day length
d.
ocean currents
e.
salinity
 

 12. 
Deserts typically occur in a band at 30 degrees north and south latitude or at different latitudes in the interior of continents. This supports the idea that
a.
descending air masses tend to be dry.
b.
trade winds have a little moisture.
c.
water is heavier than air and is not carried far over land.
d.
ascending air tends to be moist.
e.
these locations get more than their share of sunlight.
 

 13. 
In an altitudinal gradient, all of the following would change in the same way as in a latitudinal gradient except
a.
temperature.
b.
humidity.
c.
vegetation.
d.
day length.
e.
communities.
 

 14. 
Thorough mixing of water in temperate lakes during the spring and fall turnovers is made possible by which of the following?
a.
warm water layered at the top
b.
cold water layered at the bottom
c.
a pronounced thermocline under the surface
d.
changing water temperature profiles
e.
currents generated by nektonic animals
 

 15. 
Which of the following is responsible for the summer and winter stratification of lakes?
a.
Water is densest at 4°C.
b.
Oxygen is most abundant in deeper waters.
c.
Winter ice sinks in the summer.
d.
Stratification is caused by a thermocline.
e.
Stratification always follows the fall and spring turnovers.
 

 16. 
Generally speaking, deserts are located in places where air masses are usually
a.
cold.
b.
humid.
c.
rising.
d.
falling.
e.
expanding.
 

 17. 
Which of the following causes Earth's seasons?
a.
global air circulation
b.
global wind patterns
c.
ocean currents
d.
changes in Earth's distance from the sun
e.
the tilt of Earth's axis
 

 18. 
Which of the following events might you predict to occur if the tilt of Earth's axis relative to its plane of orbit was increased beyond 23.5 degrees?
a.
Summers in the United States might become warmer.
b.
Winters in Australia might become more severe.
c.
Seasonal variation at the equator might decrease.
d.
Only A and B are correct.
e.
A, B, and C are correct.
 

 19. 
Imagine some cosmic catastrophe jolts Earth so that its axis is perpendicular to the orbital plane between Earth and the sun. The most obvious effect of this change would be
a.
the elimination of tides.
b.
an increase in the length of night.
c.
an increase in the length of a year.
d.
the elimination of the greenhouse effect and a cooling of the equator.
e.
the elimination of seasonal variation.
 

 20. 
The success with which plants extend their range northward following glacial retreat is best determined by
a.
whether there is simultaneous migration of herbivores.
b.
their tolerance to shade.
c.
their seed dispersal rate.
d.
their size.
e.
their growth rate.
 

 21. 
As climate changes because of global warming, species' ranges in the northern hemisphere may move northward. The trees that are most likely to avoid extinction in such an environment are those that
a.
have wind-dispersed seeds.
b.
have animal-dispersed seeds.
c.
produce well-provisioned seeds.
d.
A and B only
e.
A, B, and C
 

 22. 
Which marine zone would have the lowest rates of primary productivity (photosynthesis)?
a.
pelagic
b.
abyssal
c.
neritic
d.
continental shelf
e.
intertidal
 

 23. 
The benthic zone in an aquatic biome
a.
often supports communities of organisms that feed largely on detritus.
b.
is the site of most photosynthesis within the biome.
c.
is where one would most expect to find a thermocline.
d.
B and C only
e.
A, B, and C
 

 24. 
Phytoplankton is most frequently found in which of the following zones?
a.
oligotrophic
b.
photic
c.
benthic
d.
abyssal
e.
aphotic
 

 25. 
You are planning a dive in a lake, and are eager to watch underwater organisms both close up and far away. You would do well to choose
a.
a nutrient-poor lake.
b.
a nutrient-rich lake.
c.
a relatively deep lake.
d.
A and C only
e.
B and C only
 

 26. 
You are interested in studying how organisms react to a gradient of abiotic conditions and how they coexist in this gradient. The best biome in which to conduct such a study is
a.
mountains.
b.
an intertidal zone.
c.
a river.
d.
tropical forest.
e.
an eutrophic lake.
 

 27. 
Which of the following statements about the ocean pelagic biome is true?
a.
The ocean is a vast, deep storehouse that always provides sustenance; it is the next "frontier" for feeding humanity.
b.
Because it is so immense, the ocean is a uniform environment.
c.
More photosynthesis occurs in the ocean than in any other biome.
d.
Pelagic ocean photosynthetic activity is disproportionately low in relation to the size of the biome.
e.
The most abundant animals are unicellular zooplankton.
 

 28. 
If a meteor impact or volcanic eruption injected a lot of dust into the atmosphere and reduced the sunlight reaching Earth's surface by 70% for one year, all of the following marine communities most likely would be greatly affected except
a.
deep-sea vent communities.
b.
coral reef communities.
c.
benthic communities.
d.
pelagic communities.
e.
estuary communities.
 

 29. 
Which of the following is not true about estuaries?
a.
Estuaries are often bordered by mudflats and salt marshes.
b.
Estuaries contain waters of varying salinity.
c.
Estuaries support a variety of animal life that humans consume.
d.
Estuaries usually contain no or few producers.
e.
Estuaries support many semiaquatic species.
 

 30. 
Which of the following statements best describes the effect of climate on biome distribution?
a.
Knowledge of annual temperature and precipitation is sufficient to predict which biome will be found in an area.
b.
Fluctuation of environmental variables is not important if areas have the same annual temperature and precipitation means.
c.
It is not only the average climate that is important in determining biome distribution, but also the pattern of climatic variation.
d.
Temperate forests, coniferous forests, and grasslands all have the same mean annual temperatures and precipitation.
e.
Correlation of climate with biome distribution is sufficient to determine the cause of biome patterns.
 

 31. 
Probably the most important factor(s) affecting the distribution of biomes is (are)
a.
wind and water current patterns.
b.
species diversity.
c.
community succession.
d.
climate.
e.
day length and rainfall.
 

 32. 
In the development of terrestrial biomes, which factor is most dependent on all the others?
a.
the species of colonizing animals
b.
prevailing temperature
c.
prevailing rainfall
d.
mineral nutrient availability
e.
soil structure
 

 33. 
An area in which different terrestrial biomes grade into each other is known as a(n)
a.
littoral zone.
b.
vertically stratified canopy.
c.
ecotone.
d.
abyssal zone.
e.
cline.
 

 34. 
Which of the following statements about biomes is incorrect?
a.
Biomes are major terrestrial communities.
b.
Within biomes there may be extensive patchiness.
c.
Climographs are often used to demonstrate climatic differences among biomes.
d.
Temperature and precipitation account for most of the variation between biomes.
e.
Biomes can be recognized as separate entities because they have sharp, well-defined boundaries.
 

 35. 
Two plant species live in the same biome but on different continents. Although the two species are not at all closely related, they may appear quite similar as a result of
a.
parallel evolution.
b.
convergent evolution.
c.
allopatric speciation.
d.
introgression.
e.
gene flow.
 

 36. 
Fire suppression by humans
a.
will always result in an increase in the number of species in a given biome.
b.
can change the species composition within biological communities.
c.
will result ultimately in sustainable production of increased amounts of wood for human use.
d.
is necessary for the protection of threatened and endangered forest species.
e.
both C and D
 

 37. 
Which of the following statements best describes the interaction between fire and ecosystems?
a.
The chance of fire in a given ecosystem is highly predictable over the short term.
b.
Many kinds of plants and plant communities have adapted to frequent fires.
c.
The prevention of forest fires has allowed more productive and stable plant communities to develop.
d.
Chaparral communities have evolved to the extent that they rarely burn.
e.
Fire is unnatural in ecosystems and should be prevented.
 

 38. 
Which biome is able to support many large animals despite receiving moderate amounts of rainfall?
a.
tropical rain forest
b.
temperate forest
c.
chaparral
d.
taiga
e.
savanna
 

 39. 
In which community would organisms most likely have adaptations enabling them to respond to different photoperiods?
a.
tropical forest
b.
coral reef
c.
savanna
d.
temperate forest
e.
abyssal
 

 40. 
The growing season would generally be shortest in which of the following biomes?
a.
savanna
b.
temperate broadleaf forest
c.
temperate grassland
d.
tropical rain forest
e.
taiga
 

 41. 
During a field trip, an instructor touched the body of a moth resting on a tree trunk. The moth raised its forewings to reveal large eye-spots on its hind wings. The instructor asked the class why the moth lifted its wings. One student answered that certain sensory receptors had fired and triggered a neuronal reflex culminating in the contraction of certain muscles. A second student responded that the behavior might frighten predators. Which statement best describes the students' explanations?
a.
The first response is correct, but the second is incorrect.
b.
The first response answers a proximate question, whereas the second answers an ultimate question.
c.
The first response is biological, whereas the second is philosophical.
d.
The first explanation is testable as a scientific hypothesis, whereas the second is not.
e.
Both explanations are reasonable and simply represent a difference of opinion.
 
 
Use the information below to answer the following questions.

When a female cat comes into heat, she urinates more frequently and in a large number of places. Male cats from the neighborhood congregate near urine deposits and fight with each other.
 

 42. 
Which of the following would be an ultimate cause of the male cats' response to the female's urinating behavior?
a.
The males have learned to recognize the specific odor of the urine of a female in heat.
b.
By smelling the odor, various neurons in the males' brains were stimulated.
c.
Male cats respond to the odor because it is a means of locating females in heat.
d.
Male cats' hormones are triggered by the odor released by the female.
e.
The odor serves as a releaser for the instinctive behavior of the males.
 

 43. 
Which of the following is a behavioral pattern that results from a proximate cause?
a.
A cat kills a mouse to obtain food.
b.
A male sheep fights with another male because it helps it to improve its social position and find a mate.
c.
A female bird lays its eggs because the amount of daylight is decreasing slightly each day.
d.
A goose squats and freezes motionless because that helps it to escape a predator.
e.
A cockroach runs into a crack in the wall and avoids being stepped on.
 

 44. 
Which of the following is a behavioral pattern resulting from an ultimate cause?
a.
A male robin attacks a red tennis ball because it resembles the breast of another male.
b.
A male robin attacks a red tennis ball because it is spring and hormonal changes increase its aggression.
c.
A male robin attacks a red tennis ball because a part of its brain is stimulated by objects that are red.
d.
A male robin attacks a red tennis ball because several times in the past red tennis balls have been thrown at it, and it has learned that they are dangerous.
e.
A male robin attacks a red tennis ball because it confuses it with an encroaching male who will steal his territory.
 

 45. 
The proximate causes of behavior are interactions with the environment, but behavior is ultimately shaped by
a.
hormones.
b.
evolution.
c.
sexuality.
d.
pheromones.
e.
the nervous system.
 

 46. 
Which of the following groups of scientists is closely associated with ethology?
a.
Watson, Crick, and Franklin
b.
McClintock, Goodall, and Lyon
c.
Fossey, Hershey, and Chase
d.
von Frisch, Lorenz, and Tinbergen
e.
Hardy, Weinberg, and Castle
 

 47. 
Which of the following statements is (are) true of fixed action patterns?
a.
They are highly stereotyped, instinctive behaviors.
b.
They are triggered by sign stimuli in the environment and, once begun, are continued to completion.
c.
An inappropriate stimulus can sometimes trigger them.
d.
A and B only
e.
A, B, and C
 

 48. 
What types of questions did Tinbergen study?
a.
genetics, biochemistry, development, behavior
b.
mechanism, development, evolution, fitness
c.
communication, genetics, behavior
d.
sexual selection, genetics, development, neurobiology
e.
evolution, behavior, sexual selection, development
 

 49. 
The time during imprinting when specific behaviors can be learned is called the
a.
window of imprinting.
b.
major period.
c.
sensitive period.
d.
timing imprint.
e.
significant window.
 

 50. 
Which of the following is least related to the others?
a.
fixed action pattern
b.
pheromones
c.
sign stimulus
d.
hormones
e.
optimal foraging
 

 51. 
Sow bugs become more active in dry areas and less active in humid areas. This is an example of
a.
taxis.
b.
tropism.
c.
kinesis.
d.
cognition.
e.
net reflex.
 

 52. 
You turn on a light and observe cockroaches scurrying to dark hiding places. What have you observed?
a.
taxis
b.
learned behavior
c.
migration
d.
visual communication
e.
operant conditioning
 

 53. 
Imagine that you are designing an experiment aimed at determining whether the initiation of migratory behavior is largely under genetic control. Of the following options, the best way to proceed is to
a.
observe different genetically distinct populations in the field and see if they have different migratory habits.
b.
perform within-population matings with birds from different populations that have different migratory habits. Do this in the laboratory and see if offspring display parental migratory behavior.
c.
bring animals into the laboratory and determine the conditions under which they become restless and attempt to migrate.
d.
perform within-population matings with birds from different populations that have different migratory habits. Rear the offspring in the absence of their parents and observe offspring migratory behavior.
e.
All of the above are equally productive ways to approach the question.
 

 54. 
Animal communication involves what type of sensory information?
a.
visual
b.
auditory
c.
chemical
d.
A and C only
e.
A, B, and C
 
 
Below is a list of signal types that animals use for communication. Choose the one that best fits the criteria in the following questions.

A)olfactory
B)visual
C)auditory
D)tactile
E)electrical
 

 55. 
A long-lasting signal that works at night.
a.
A
b.
B
c.
C
d.
D
e.
E
 

 56. 
A fast signal that requires daylight and no obstructions.
a.
A
b.
B
c.
C
d.
D
e.
E
 

 57. 
Loss of responsiveness to stimuli that convey little or not information is called
a.
adapting.
b.
spacing.
c.
conditioning.
d.
imprinting.
e.
habituation.
 

 58. 
Which of the following would you classify as habituation?
a.
You enter a room and hear a fan motor. After a period of time, you are no longer aware of the sound of the fan motor.
b.
You are driving your car and you hear a horn. You step on the brakes, but notice the sound came from a car on a side street. You resume your previous speed.
c.
One morning you are awoken to a beep-beep-beep from a garbage truck working on a new early morning schedule. The next week the garbage truck arrives at the same time and makes the same noise, but does not wake you up.
d.
A and C only
e.
A, B, and C
 

 59. 
Learning in which an associated stimulus may be used to elicit the same behavioral response as the original sign stimulus is called
a.
concept formation.
b.
trial-and-error.
c.
classical conditioning.
d.
operant conditioning.
e.
habituation.
 

 60. 
Which of the following statements about learning and behavior is incorrect?
a.
Operant conditioning involves associating a behavior with a reward or punishment.
b.
Associative learning involves linking one stimulus with another.
c.
Classical conditioning involves trial-and-error learning.
d.
Behavior can be modified by learning, but some apparent learning is due to maturation.
e.
Imprinting is a learned behavior with an innate component acquired during a sensitive period.
 
 
Use the terms below to answer the following questions. Match the term that best fits each of the following descriptions of behavior. Each term may be used once, more than once, or not at all.

A.sign stimulus
B.habituation
C.imprinting
D.classical conditioning
E.operant conditioning
 

 61. 
A stickleback fish will attack a fish model as long as the model has red coloring.
a.
A
b.
B
c.
C
d.
D
e.
E
 

 62. 
Parental protective behavior in turkeys is triggered by the cheeping sound of young chicks.
a.
A
b.
B
c.
C
d.
D
e.
E
 

 63. 
Classical conditioning and operant conditioning are two forms of associative learning. They differ in that
a.
classical conditioning takes longer.
b.
operant conditioning usually involves more intelligence.
c.
operant conditioning involves consequences for the animal's behavior.
d.
classical conditioning is restricted to mammals and birds.
e.
classical conditioning is much more useful for training domestic animals.
 

 64. 
Among song birds, a "crystallized" song is one that
a.
is high pitched.
b.
is aimed at attracting mates.
c.
extremely young chicks sing.
d.
is the final song that some species produce.
e.
warns of predators.
 

 65. 
Stevan Arnold discovered that coastal and inland garter snakes reacted differently to banana slug prey. What probably accounts for such a difference?
a.
Ancestors of coastal snakes that were able to eat the abundant slugs had increased fitness. No such selection occurred inland, where slugs were absent.
b.
Slugs are difficult to see, and inland snakes, which have poor vision compared with coastal snakes, are less able to see them.
c.
Garter snakes learn about prey from other garter snakes. Inland snakes are less social, and this lowers prey diversity.
d.
Inland snakes overlap with distasteful slugs, and thus learn to avoid them. Coastal slugs are not distasteful.
e.
Garter snakes are conditioned to eat what their mother eats. The mothers of Arnold's coastal snakes happened to prefer slugs.
 

 66. 
Animals tend to maximize their energy intake-to-expenditure ratio. What is this behavior called?
a.
agonistic behavior
b.
optimal foraging
c.
dominance hierarchies
d.
animal cognition
e.
territoriality
 

 67. 
Feeding behavior that has a high energy intake-to-expenditure ratio is called
a.
herbivory.
b.
autotrophy.
c.
heterotrophy.
d.
search scavenging.
e.
optimal foraging.
 

 68. 
Which of the following is not a concept associated with sociobiology?
a.
parental investment
b.
inclusive fitness
c.
associative learning
d.
reciprocal altruism
e.
kin selection
 

 69. 
Optimal foraging involves all of the following except
a.
maximizing energy gained by the forager.
b.
minimizing energy expended by the forager.
c.
securing essential nutrients for the forager.
d.
minimizing the risk of predation on the forager.
e.
maximizing the population size of the forager.
 

 70. 
In the evolution of whelk-eating behavior in the crows studied by Reto Zach, which of the following was being minimized by natural selection?
a.
the average number of drops required to break the shell
b.
the average height a bird flew to drop a shell
c.
the average total energy used to break shells
d.
the average size of the shells dropped by the birds
e.
the average thickness of the shells dropped by the birds
 

 71. 
Which of the following might affect the foraging behavior of an animal in the context of optimal foraging?
a.
risk of predation
b.
prey size
c.
prey defenses
d.
A and B only
e.
A, B, and C
 

 72. 
The evolution of mating systems is most likely affected by
a.
population size.
b.
care required by young.
c.
certainty of paternity.
d.
B and C only
e.
A, B , and C
 

 73. 
Fred and Joe, two unrelated, mature male gorillas, encounter one another. Fred is courting a female. Fred grunts as Joe comes near. As Joe continues to advance, Fred begins drumming (pounding his chest) and bares his teeth. At this, Joe rolls on the ground on his back, then gets up and quickly leaves. This behavioral pattern is repeated several times during the mating season. Choose the most specific behavior described by this example.
a.
agonistic behavior
b.
territorial behavior
c.
learned behavior
d.
social behavior
e.
fixed action pattern
 

 74. 
Which of the following is least related to the others?
a.
altruism
b.
polygamy
c.
monogamy
d.
polygyny
e.
polyandry
 

 75. 
Which of the following does not have a coefficient of relatedness of 0.5?
a.
a father to his daughter
b.
a mother to her son
c.
an uncle to his nephew
d.
a brother to his brother
e.
a sister to her brother
 
 
Match each phrase to a scientist from the list below.

A)Karl von Frisch
B)Niko Tinbergen
C)Konrad Lorenz
D)William Hamilton
E)Ivan Pavlov
 

 76. 
devised a rule that predicts when natural selection should favor altruism
a.
A
b.
B
c.
C
d.
D
e.
E
 

 77. 
studied imprinting of graylag geese
a.
A
b.
B
c.
C
d.
D
e.
E
 

 78. 
The central concept of sociobiology is that
a.
human behavior is rigidly predetermined.
b.
the behavior of an individual cannot be modified.
c.
our behavior consists mainly of fixed action patterns.
d.
most aspects of our social behavior have an evolutionary basis.
e.
the social behavior of humans is homologous to the social behavior of honeybees.
 
 
Match each of the phrases to a scientist from the list below.

A)E. O. Wilson
B)Jane Goodall
C)B. S. Haldane
D)Niko Tinbergen
E)William Hamilton
 

 79. 
formulated four questions that motivate modern behavioral biology
a.
A
b.
B
c.
C
d.
D
e.
E
 

 80. 
suggested that human social behavior may have a genetic basis
a.
A
b.
B
c.
C
d.
D
e.
E
 

 81. 
developed the concept of inclusive fitness
a.
A
b.
B
c.
C
d.
D
e.
E
 

 82. 
A biologist reported that a sample of ocean water had 5 million diatoms of the species Coscinodiscus centralis per cubic meter. What was the biologist measuring?
a.
density
b.
dispersion
c.
carrying capacity
d.
quadrats
e.
range
 

 83. 
All of the following phrases could characterize a population except
a.
interacting individuals.
b.
dispersion.
c.
density.
d.
several species.
e.
boundaries.
 

 84. 
To measure the population density of monarch butterflies occupying a particular park, 100 butterflies are captured, marked with a small dot on a wing, and then released. The next day, another 100 butterflies are captured, including the recapture of 20 marked butterflies. One would estimate the population to be
a.
200.
b.
500.
c.
1,000.
d.
10,000.
e.
900,000.
 

 85. 
You are studying the mice that live in a pasture near your home. There are lots of mice in this pasture, but you realize that you rarely observe any reproductive females. This most likely indicates
a.
that there is selective predation on female mice.
b.
that female mice die before reproducing.
c.
that this habitat is not a good place for mice to reproduce.
d.
that you are observing immigrant mice.
e.
both C and D
 

 86. 
You are observing a population of lizards when you notice that the number of adults has increased and is higher than previously observed. One explanation for such an observation would include
a.
reduction in death rate.
b.
increased immigration.
c.
increased emigration.
d.
decreased emigration.
e.
both B and D
 

 87. 
The most common kind of dispersion in nature is
a.
clumped.
b.
random.
c.
uniform.
d.
indeterminate.
e.
dispersive.
 

 88. 
The pattern of dispersion for a certain species of kelp is clumped. The pattern of dispersion for a certain species of snail that lives only on this kelp would likely be
a.
absolute.
b.
clumped.
c.
demographic.
d.
random.
e.
uniform.
 

 89. 
Uniform spacing patterns in plants such as the creosote bush are most often associated with
a.
chance.
b.
patterns of high humidity.
c.
the random distribution of seeds.
d.
antagonistic interactions among individuals in the population.
e.
the concentration of resources within the population's range.
 

 90. 
Which of the following would be most likely to exhibit uniform dispersion?
a.
red squirrels, which hide food and actively defend territories
b.
cattails, which grow primarily at edges of lakes and streams
c.
dwarf mistletoes, which parasitize particular species of forest trees
d.
tassel-eared squirrels, which are nonterritorial
e.
lake trout, which seek out deep water
 

 91. 
Life tables are useful in determining which of the following?

I.carrying capacity
II.mortality rates
III.the fate of a cohort of newborn organisms throughout their lives
a.
I only
b.
II only
c.
III only
d.
I and III only
e.
II and III only
 
 
Use the survivorship curves in the figure below to answer the following questions.

nar006-1.jpg
 

 92. 
Which curve best describes survivorship in elephants?
a.
A
b.
B
c.
C
d.
D
e.
E
 

 93. 
Which curve best describes survivorship in a marine crustacean that molts?
a.
A
b.
B
c.
C
d.
D
e.
E
 

 94. 
Which curve best describes survivorship in humans who live in developed nations?
a.
A
b.
B
c.
C
d.
D
e.
E
 

 95. 
Which curve best describes survivorship in squirrels?
a.
A
b.
B
c.
C
d.
D
e.
E
 

 96. 
In order to construct a reproductive table for a sexual species, you need to
a.
assess sperm viability.
b.
keep track of all of the offspring of a cohort.
c.
keep track of the females in a cohort.
d.
keep track of all of the offspring of the females in a cohort.
e.
keep track of the ratio of deaths to births in a cohort.
 

 97. 
Life history strategies usually result from
a.
environmental pressures.
b.
natural selection.
c.
conscious choice.
d.
A and B only
e.
A, B, and C
 

 98. 
Natural selection has led to the evolution of diverse natural history strategies, which have in common
a.
many offspring per reproductive episode.
b.
limitation by density-dependent limiting factors.
c.
adaptation to stable environments.
d.
maximum lifetime reproductive success.
e.
relatively large offspring.
 

 99. 
Natural selection involves energetic trade-offs between or among life history traits such as
a.
number of offspring per reproductive episode.
b.
number of reproductive episodes per lifetime.
c.
age at first reproduction.
d.
A and C only
e.
A, B, and C
 

 100. 
Which of the following aspects of an organism's life is least relevant to its life history?
a.
number of offspring per reproductive bout
b.
age at which it first reproduces
c.
frequency of reproduction
d.
frequency of dispersal
e.
all of the above
 

 101. 
A population of ground squirrels has an annual per capita birth rate of 0.06 and an annual per capita death rate of 0.02. Estimate the number of individuals added to (or lost from) a population of 1,000 individuals in one year.
a.
120 individuals added
b.
40 individuals added
c.
20 individuals added
d.
400 individuals added
e.
20 individuals lost
 

 102. 
A small population of white-footed mice has the same intrinsic rate of increase (r) as a large population. If everything else is equal,
a.
the large population will add more individuals per unit time.
b.
the small population will add more individuals per unit time.
c.
the two populations will add equal numbers of individuals per unit time.
d.
the J-shaped growth curves will look identical.
e.
the growth trajectories of the two populations will proceed in opposite directions.
 

 103. 
Imagine that you are managing a large ranch. You know from historical accounts that wild sheep used to live there, but they have been exterminated. You decide to reintroduce them. After doing some research to determine what might be an appropriate founding population, you do so. You then watch the population increase, and graph the number of individuals (vertical axis) against the number of generations (horizontal axis). The graph will
a.
be a diagonal line, getting higher with each generation.
b.
look like an "S," increasing with each generation.
c.
look like an upside-down "U."
d.
look like a "J," increasing with each generation.
e.
look like none of the above.
 
 
Use the following choices to answer the question below. Each choice may be used once, more than once,or not at all.

A.nar007-1.jpg
B.nar007-2.jpg
C.nar007-3.jpg
D.nar007-4.jpg
E.nar007-5.jpg
 

 104. 
Exponential growth of a population is represented by dN/dt =
a.
A
b.
B
c.
C
d.
D
e.
E
 

 105. 
As N approaches K for a certain population, which of the following is predicted by the logistic equation?
a.
The growth rate will not change.
b.
The growth rate will approach zero.
c.
The population will show an Allee effect.
d.
The population will increase exponentially.
e.
The carrying capacity of the environment will increase.
 

 106. 
In models of sigmoidal (logistic) population growth,
a.
population growth rate slows dramatically as N approaches K.
b.
new individuals are added to the population most rapidly at intermediate population sizes.
c.
density-dependent factors affect the rate of population growth.
d.
All of the above are true.
e.
Only A and C are true.
 

 107. 
The Allee effect is a phenomenon that occurs when population size
a.
becomes too small.
b.
becomes too large.
c.
approaches carrying capacity.
d.
exceeds carrying capacity.
e.
more than one of the above
 
 
Refer to the terms below to answer the following questions. Each term may be used once, more than once, or not at all.

Acohort
B.dispersion
C.Allee effect
D.iteroparous
E.semelparous
 

 108. 
Pacific salmon or annual plants
a.
A
b.
B
c.
C
d.
D
e.
E
 

 109. 
reproduce more than once in a lifetime
a.
A
b.
B
c.
C
d.
D
e.
E
 

 110. 
A predator might be more likely to be spotted if a large number of prey are all together than it would be by a single prey animal.
a.
A
b.
B
c.
C
d.
D
e.
E
 

 111. 
Which of the following statements about the logistic model of population growth is incorrect?
a.
It fits an S-shaped curve.
b.
It incorporates the concept of carrying capacity.
c.
It describes population density shifts over time.
d.
It accurately predicts the growth of most populations.
e.
It predicts an eventual state in which birth rate equals death rate.
 

 112. 
Which of the following is true?
a.
K-selection can be density-independent.
b.
r-selection occurs in crowded environments.
c.
Different populations of the same species will be consistently r- or K-selected.
d.
r- and K-selection are two extremes of a range of life history strategies.
e.
r-selection tends to maximize population size, not the rate of increase in population size.
 

 113. 
The life history traits favored by selection are most likely to vary with
a.
fluctuations in K.
b.
the shape of the J curve.
c.
the maximum size of a population.
d.
population density.
e.
the terms used in the logistic equation.
 

 114. 
All of the following characteristics are typical of an r-selected population except
a.
occurrence in variable environments.
b.
high intrinsic rate of growth.
c.
onset of reproduction at an early age.
d.
extensive parental care of offspring.
e.
occurrence in open habitats.
 

 115. 
Which of the following statements about the evolution of life histories is correct?
a.
Stable environments with limited resources favor r-selected populations.
b.
K-selected populations are most often found in environments where density-independent factors are important regulators of population size.
c.
Most populations have both r- and K-selected characteristics that vary under different environmental conditions.
d.
The reproductive efforts of r-selected populations are directed at producing just a few offspring with good competitive abilities.
e.
K-selected populations rarely approach carrying capacity.
 

 116. 
Your friend comes to you with a problem. It seems his shrimp boats aren't catching nearly as much shrimp as they used to. He can't understand it because originally he caught all the shrimp he could handle. Each year he added a new boat, and for a long time each boat caught tons of shrimp. As he added more boats, there came a time when each boat caught a little less shrimp, and now, each boat is catching a lot less shrimp. Which of the following topics might help your friend understand the source of his problem?
a.
density-dependent population regulation
b.
logistic growth and intrinsic characteristics of population growth
c.
density-independent population regulation
d.
A and B only
e.
A, B, and C
 

 117. 
Which of the following is an incorrect statement about the regulation of populations?
a.
The logistic equation reflects the effect of density-dependent factors, which can ultimately stabilize populations around the carrying capacity.
b.
Density-independent factors have an increasingly greater effect as a population's density increases.
c.
High densities in a population may cause physiological changes that inhibit reproduction.
d.
Because of the overlapping nature of population-regulating factors, it is often difficult to precisely determine their cause-and-effect relationships.
e.
The occurrence of population cycles in some populations may be the result of crowding or lag times in the response to density-dependent factors.
 

 118. 
In a mature forest of oak, maple, and hickory trees, a disease causes a reduction in the number of acorns produced by oak trees. Which of the following would least likely be a direct result of this?
a.
There might be fewer squirrels because they feed on acorns.
b.
There might be fewer mice and seed-eating birds because squirrels would eat more seeds and compete with the mice and birds.
c.
There might be an increase in the number of hickory trees because the competition between hickory nuts and acorns for germination sites would be reduced or eliminated.
d.
There might be fewer owls because they feed on baby squirrels, mice, and young seed-eating birds, whose populations would be reduced.
e.
There might be a decrease in the number of maple seeds as the disease spreads to other trees in the forest.
 

 119. 
You are studying a population of finches on one island in an archipelago. You find that your population is much larger than you would predict from your careful recording of hatching, fledgling, and death rates. The likely explanation for this observation is
a.
you are dealing with a metapopulation.
b.
your island is the source of emigration.
c.
your island is the target of immigration.
d.
A and C only
e.
A, B, and C
 

 120. 
Consider several human populations of equal size and net reproductive rate, but different in age structure. The population that is likely to grow the most during the next 30 years is the one with the greatest fraction of people in which age range?
a.
50 to 60 years
b.
40 to 50 years
c.
30 to 40 years
d.
20 to 30 years
e.
10 to 20 years
 
 
The following questions refer to the figure below, which depicts the age structure of three populations.

nar009-1.jpg
 

 121. 
Which population is in the process of decreasing?
a.
I
b.
II
c.
III
d.
I and II
e.
II and III
 

 122. 
Which of the following is not used in calculating an ecological footprint?
a.
arable land
b.
pasture and forest lands
c.
fossil energy land
d.
demographically transitional land
e.
built-up land
 

 123. 
The unit(s) of measurement for an ecological footprint is (are)
a.
weight of biomass per year.
b.
number of species per ecosystem.
c.
number of individuals per population.
d.
number of people per continent.
e.
area of land per person.
 

 124. 
All of the following have contributed to the growth of the human population except
a.
environmental degradation.
b.
improved nutrition.
c.
vaccines.
d.
pesticides.
e.
improved sanitation.
 

 125. 
Which of the following variables is (are) important in contributing to the rapid growth of human populations?
a.
the high percentage of young people relative to the whole population
b.
the average age to first give birth
c.
the carrying capacity of the environment
d.
A and B only
e.
A, B, and C
 

 126. 
Communities can be linked by which of the following?

I.predation
II.systematics
III.competition
a.
I only
b.
III only
c.
I and II only
d.
I and III only
e.
I, II, and III
 

 127. 
Which of the following statements is consistent with the competitive exclusion principle?
a.
Bird species generally do not compete for nesting sites.
b.
The density of one competing species will have a positive impact on the population growth of the other competing species.
c.
Two species with the same fundamental niche will exclude other competing species.
d.
Even a slight reproductive advantage will eventually lead to the elimination of inferior species.
e.
Evolution tends to increase competition between related species.
 

 128. 
The presence of all of the following tend to increase species diversity except
a.
competitive exclusion.
b.
keystone predators.
c.
patchy environments.
d.
moderate disturbances.
e.
migration of populations.
 

 129. 
According to the competitive exclusion principle, two species cannot continue to occupy the same
a.
habitat.
b.
niche.
c.
territory.
d.
range.
e.
biome.
 

 130. 
The entire box shown in the figure below represents the niche of species A. Species A is biologically constrained from the striped area of its niche by species B. This is an example of

mc130-1.jpg
a.
dynamic stability.
b.
facilitation.
c.
commensalism.
d.
competitive exclusion.
e.
secondary succession.
 

 131. 
The sum total of an organism's interaction with the biotic and abiotic resources of its environment is called its
a.
habitat.
b.
logistic growth.
c.
biotic potential.
d.
microclimax.
e.
ecological niche.
 

 132. 
Two barnacles, Balanus and Chthamalus, can both survive on the lower rocks just above the low-tide line on the Scottish coast, but only Balanus actually does so, with Chthamalus adopting a higher zone. Which of the following best accounts for this niche separation?
a.
competitive exclusion
b.
predation of Chthamalus by Balanus
c.
cooperative displacement
d.
primary succession
e.
mutualism
 

 133. 
All of the following describe possible results of competition between two species except
a.
competitive exclusion.
b.
aposematic coloration.
c.
resource partitioning.
d.
reduction in the population of one species.
e.
reduction in the populations of both species.
 

 134. 
Resource partitioning is best described by which of the following statements?
a.
Competitive exclusion results in the success of the superior species.
b.
Slight variations in niche allow similar species to coexist.
c.
Two species can coevolve and share the same niche.
d.
Species diversity is maintained by switching between prey species.
e.
A climax community is reached when no new niches are available.
 

 135. 
As you study two closely related predatory insect species, the two-spot and the three-spot avenger beetles, you notice that each species seeks prey at dawn in areas without the other species. Where their ranges overlap, however, the two-spot avenger beetle hunts at night and the three-spot hunts in the morning. When you bring them into the laboratory, their offspring behave in the same manner. You have discovered an example of
a.
mutualism.
b.
character displacement.
c.
Batesian mimicry.
d.
facultative commensalism.
e.
none of the above
 

 136. 
Resource partitioning would be most likely to occur between
a.
sympatric populations of a predator and its prey.
b.
sympatric populations of species with similar ecological niches.
c.
sympatric populations of a flowering plant and its specialized insect pollinator.
d.
allopatric populations of the same animal species.
e.
allopatric populations of species with similar ecological niches.
 

 137. 
An insect that has evolved to resemble a plant twig will probably be able to avoid
a.
parasitism.
b.
symbiosis.
c.
predation.
d.
competition.
e.
commensalism.
 

 138. 
Which of the following is an example of cryptic coloration?
a.
bands on a coral snake
b.
brown color of tree bark
c.
markings of a viceroy butterfly
d.
colors of an insect-pollinated flower
e.
a "walking stick" insect that resembles a twig
 

 139. 
Batesian mimicry systems involve all of the following except
a.
the models being noxious or disagreeable.
b.
the mimics having no defense mechanism.
c.
the ability of predators to "learn" characteristics of their prey.
d.
the models being cryptically colored.
e.
the models being easily recognized.
 

 140. 
Which of the following is an example of Müllerian mimicry?
a.
two species of unpalatable butterfly that have the same color pattern
b.
a day-flying hawkmoth that looks like a wasp
c.
a katydid whose wings look like a dead leaf
d.
two species of rattlesnake that both rattle their tails
e.
two species of moths that with wing spots that look like owl's eyes
 

 141. 
Which of the following is an example of Batesian mimicry?
a.
an insect that resembles a twig
b.
a butterfly that resembles a leaf
c.
a nonvenomous snake that looks like a venomous snake
d.
a fawn with fur coloring that camouflages it in the forest environment
e.
a snapping turtle that uses its tongue to mimic a worm, thus attracting fish
 

 142. 
Which of the following is an example of aposematic coloration?
a.
stripes of a skunk
b.
eye color in humans
c.
green color of a plant
d.
colors of an insect-pollinated flower
e.
a katydid whose wings look like a dead leaf
 

 143. 
Two species of insects from different geographic areas display characteristic black and red stripes. Which of the following is unlikely to be related to this phenomenon?
a.
aposematic coloration
b.
convergent evolution
c.
common ancestry
d.
mimicry
e.
defense against a predator
 

 144. 
Which of the following is not an example of a plant defense against herbivory?
a.
nicotine
b.
cryptic coloration
c.
spines
d.
thorns
e.
strychnine
 

 145. 
Evidence shows that some grasses benefit from being grazed. Which of the following terms would best describe this plant-herbivore interaction?
a.
mutualism
b.
commensalism
c.
parasitism
d.
competition
e.
predation
 

 146. 
Which of the following interactions can correctly be labeled coevolution?
a.
the tendency of coyotes to respond to human habitat encroachment by including pet dogs and cats in their diets
b.
a genetic change in a virus that allows it to exploit a new host, which responds to virus-imposed selection by changing its genetically controlled habitat preferences
c.
a genetic change in foxes that allows them to tolerate human presence (and food)
d.
the adaptation of cockroaches to human habitation
e.
the ability of rats to survive in a variety of novel environments
 

 147. 
Which of the following types of species interaction is incorrectly paired to its effects on the density of the two interacting populations?
a.
predation-one increases, one decreases
b.
parasitism-one increases, one decreases
c.
commensalism-both increase
d.
mutualism-both increase
e.
competition-both decrease
 

 148. 
The species richness of a community refers to the
a.
number of food chains.
b.
number of different species.
c.
energy content of all species.
d.
relative numbers of individuals in each species.
e.
total number of all organisms.
 

 149. 
Which of the following statements about communities is not correct?
a.
Many plant species in communities seem to be independently distributed.
b.
Some animal species distributions within a community are linked to other species.
c.
The distribution of almost all organisms is probably affected, to some extent, by both abiotic gradients and interactions with other species.
d.
Ecologists refer to species richness as the number of species within a community.
e.
The trophic structure of a community describes abiotic factors such as rainfall and temperature affecting members of the community.
 

 150. 
With a few exceptions, most of the food chains studied by ecologists have a maximum of how many links?
a.
2
b.
3
c.
5
d.
10
e.
15
 

 151. 
Prairie dogs once covered the expanses of the Great Plains. Their grazing made the grass more nutritious for the huge herds of bison, and a variety of snakes, raptors, and mammals preyed on the rodents. In fact, the black-footed ferret (now endangered) specialized in prairie dog predation. Today, growing neighborhoods have covered many prairie dog towns. Which of the following statements about prairie dogs is not true?
a.
Their realized niche has diminished.
b.
They are commensals with bison.
c.
They are reasonably considered a keystone species.
d.
Their fundamental niche remains unaltered.
e.
Their fundamental niche has diminished.
 

 152. 
Which of the following members of a marine food chain is most analogous to a grasshopper in a terrestrial food chain?
a.
phytoplankton
b.
zooplankton
c.
detritivore
d.
fish
e.
shark
 

 153. 
The energetic hypothesis and dynamic stability hypothesis are explanations to account for
a.
plant defenses against herbivores.
b.
the length of food chains.
c.
the evolution of mutualism.
d.
resource partitioning.
e.
the competitive exclusion principle.
 

 154. 
The dominant species in a community is
a.
characterized by very large individuals with long lives.
b.
the best competitor in the community.
c.
the best predator in the community.
d.
the population with the most biomass.
e.
the most energetically efficient species in the community.
 

 155. 
In a tide pool, 15 species of invertebrates were reduced to eight after one species was removed. The species removed was likely a(n)
a.
community facilitator.
b.
keystone species.
c.
herbivore.
d.
resource partitioner.
e.
mutualistic organism.
 

 156. 
Which of the following statements about community interactions is not correct?
a.
Closely related species may be able to coexist if there is at least one significant difference in their niches.
b.
Plants can defend themselves against herbivores by the production of compounds that are irritating or toxic.
c.
Keystone predators reduce diversity in a community by holding down or wiping out prey populations.
d.
Mutualism is an important biotic interaction that occurs in communities.
e.
Some predators use mimicry to attract prey.
 

 157. 
Elephants are not the most common species in African grasslands. The grasslands contain scattered woody plants, but they are kept in check by the uprooting activities of the elephants. Take away the elephants, and the grasslands convert to forests or to shrublands. The newly growing forests support fewer species than the previous grasslands. Elephants can be defined as what type of species in this community?
a.
redundant
b.
dominant
c.
keystone
d.
dominant and keystone
e.
none of the above
 

 158. 
When lichens grow on bare rock, they may eventually accumulate enough organic material around them to supply the foothold for later rooted vegetation. These early pioneering lichens can be said to do what to the later arrivals?
a.
tolerate
b.
inhibit
c.
facilitate
d.
exclude
e.
concentrate
 

 159. 
Which of the following statements concerning the control of community structure is false?
a.
A bottom-up community is controlled by nutrients.
b.
A top-down community is controlled by predators.
c.
Increasing the biomass of vegetation in a bottom-up community will increase herbivores.
d.
Increasing the biomass of vegetation in a bottom-up community will increase predators.
e.
Increasing the number of predators in a top-down community will decrease the biomass of vegetation.
 

 160. 
Which of the following is considered by ecologists a measure of the ability of a community either to resist change or to recover to its original state after change?
a.
stability
b.
succession
c.
partitioning
d.
productivity
e.
competitive exclusion
 

 161. 
According to the nonequilibrium model,
a.
communities will remain in a state of equilibrium in the absence of human activities.
b.
community structure remains constant in the absence of interspecific competition.
c.
communities are assemblages of closely linked species that function as tightly integrated units.
d.
interspecific interactions induce changes in community composition over time.
e.
communities are constantly changing because of disturbances.
 

 162. 
Disturbances to ecological communities
a.
are frequently related to human activities.
b.
can remove organisms and alter resource availability.
c.
can create vacated ecological niches that other species can colonize.
d.
All of the above are true.
e.
Only A and B are true.
 

 163. 
In a particular case of secondary succession, three species of wild grass all invaded a field. By the second season, a single species dominated the field. A possible factor in this secondary succession was
a.
equilibrium.
b.
facilitation.
c.
immigration.
d.
inhibition.
e.
mutualism.
 

 164. 
You are most likely to observe primary succession when you visit a(n)
a.
tropical rain forest.
b.
abandoned field.
c.
old riverbed.
d.
fairly recent volcanic island.
e.
deep sea vent.
 
 
Refer to the list of terms below to answer the following questions. Each term may be used once, more than once, or not at all.

A.parasitism
B.mutualism
C.inhibition
D.facilitation
E.commensalism
 

 165. 
the relationship between legumes and nitrogen-fixing bacteria
a.
A
b.
B
c.
C
d.
D
e.
E
 

 166. 
successional event in which one organism makes the environment more suitable for another organism
a.
A
b.
B
c.
C
d.
D
e.
E
 

 167. 
the relationship between the larvae of small wasps and caterpillars
a.
A
b.
B
c.
C
d.
D
e.
E
 

 168. 
Species richness increases
a.
as one travels north from the equator.
b.
as one travels north from the South Pole.
c.
on islands as distance from the mainland increases.
d.
as rates of evapotranspiration decrease.
e.
as community size decreases.
 

 169. 
There are more species in tropical areas than in places farther from the equator. This is probably a result of
a.
fewer predators.
b.
a longer growing season.
c.
fewer major disturbances.
d.
B and C only
e.
all of the above
 

 170. 
In conservation biology, species-area curves for key taxa make it possible to predict
a.
the size of an area that needs to be sampled.
b.
the area that a keystone species will occupy.
c.
whether or not a redundancy model will apply to a given area.
d.
how the loss of a certain habitat area is likely to affect biodiversity.
e.
whether or not an area will reach equilibrium.
 
 
Refer to the diagram below of five islands formed at about the same time near a particular mainland to answer the following questions.

nar011-1.jpg
 

 171. 
island with the greatest number of species
a.
A
b.
B
c.
C
d.
D
e.
E
 

 172. 
Which of the following statements about the biogeographical aspects of diversity is not correct?
a.
The patterns of continental drift are important considerations in the study of the past and present distributions of species.
b.
The magnitude of photosynthesis is the factor that accounts for the major variations in species diversity over large areas of Earth.
c.
Species richness on an island reaches an equilibrium point when immigration equals extinction.
d.
A species may be limited to a particular range because it never dispersed beyond that range, or it dispersed but failed to survive in other locations.
e.
Island equilibrium theory applies to the relatively short period of time when colonization is the important process determining species composition; over a longer time, actual speciation affects the composition.
 

 173. 
Which of the following traits does not characterize an individualistic community?
a.
discrete geographic boundaries
b.
strong abiotic influences on species distributions
c.
community composition changes along a gradient
d.
strong biotic influences on species distribution
e.
bottom-up organization
 

 174. 
The rivet model of community structure suggests that
a.
damaged communities can be repaired if species are added.
b.
communities are tightly integrated units that may be seriously affected by changes in the abundance of only one species.
c.
most communities are robust in the face of disturbance.
d.
top-down regulation of communities is most important.
e.
if one species disappears, another will probably take its place.
 

 175. 
A biologist measures predation rates by crab spiders on flower-visiting insects in a particular field community. Then the biologist experimentally removes as many of the spiders as she can. She discovers that predation rates remain the same but that the major predators shift from spiders to ambush bugs. Which of the following community structure models is most consistent with her findings?
a.
individualistic
b.
integrated
c.
rivet
d.
redundancy
e.
manipulative
 

 176. 
A cow's herbivorous diet indicates that it is a(n)
a.
primary consumer.
b.
secondary consumer.
c.
decomposer.
d.
autotroph.
e.
producer.
 

 177. 
To recycle nutrients, the minimum an ecosystem must have is
a.
producers.
b.
producers and decomposers.
c.
producers, primary consumers, and decomposers.
d.
producers, primary consumers, secondary consumers, and decomposers.
e.
producers, primary consumers, secondary consumers, top carnivores, and decomposers.
 

 178. 
Production, consumption, and decomposition are important ecosystem processes. Which of the following could be decomposers?
a.
bacteria
b.
vertebrates
c.
invertebrates
d.
A and C only
e.
A, B, and C
 

 179. 
Many homeowners mow their lawns during the summer and collect the clippings, which are then hauled to the local landfill. Which of the following alternatives would cause the least disturbance to local ecosystems?
a.
Don't mow the lawn-have sheep graze it and put the sheep's feces into the landfill.
b.
Collect the clippings and burn them.
c.
Either collect the clippings and add them to a compost pile, or don't collect the clippings and let them decompose on the lawn.
d.
Collect the clippings and wash them into the nearest storm sewer that feeds into the local lake.
e.
Dig up the lawn and cover the yard with asphalt.
 

 180. 
The producers in ecosystems include organisms in which of the following groups?
a.
prokaryotes
b.
algae
c.
plants
d.
B and C only
e.
A, B, and C
 

 181. 
How is it that the open ocean produces the highest net primary productivity of Earth's ecosystems, yet net primary productivity per square meter is relatively low?
a.
It contains greater concentrations of nutrients.
b.
It receives a greater amount of solar energy per unit area.
c.
It has the greatest total area.
d.
It contains more species of organisms.
e.
Its producers are generally much smaller than its consumers.
 

 182. 
Which of the following organisms fix nitrogen in aquatic ecosystems?
a.
cyanobacteria
b.
chemoautotrophs
c.
phytoplankton
d.
legumes
e.
fungi
 

 183. 
As big as it is, the ocean is nutrient-limited. If you wanted to investigate this, one reasonable avenue would be to
a.
follow whale migrations in order to determine where most nutrients are.
b.
observe Antarctic Ocean productivity and compare that to other areas.
c.
experimentally enrich some areas of the ocean and compare them to unmanipulated areas.
d.
B and C only
e.
A, B, and C
 

 184. 
Which of the following pyramids cannot be inverted?
a.
production
b.
biomass
c.
numbers
d.
A and B only
e.
A, B, and C
 

 185. 
If you wanted to convert excess grain into the greatest amount of animal biomass, to which animal would you feed the grain?
a.
chickens
b.
mice
c.
cattle
d.
carp (a type of fish)
e.
mealworms (larval insects)
 

 186. 
Organisms in which of the following groups can be primary producers?
a.
cyanobacteria
b.
zooplankton
c.
flowering plants
d.
A and C only
e.
A, B, and C
 

 187. 
In general, the total biomass in a terrestrial ecosystem will be greatest for which trophic level?
a.
producers
b.
herbivores
c.
primary consumers
d.
tertiary consumers
e.
secondary consumers
 

 188. 
Some aquatic ecosystems can have inverted biomass pyramids because
a.
phytoplankton are much larger than zooplankton.
b.
phytoplankton have a relatively short life cycle.
c.
consumption of phytoplankton by zooplankton is so rapid that the standing crop of phytoplankton remains relatively low.
d.
B and C only
e.
A, B, and C
 
 
Refer to the figure below, a diagram of a food web, for the following questions. (Arrows represent energy flow and letters represent species.)

nar012-1.jpg
 

 189. 
If this were a terrestrial food web, the combined biomass of C + D would probably be
a.
greater than the biomass of A.
b.
less than the biomass of H.
c.
greater than the biomass of B.
d.
less than the biomass of A + B.
e.
less than the biomass of E.
 

 190. 
If this were a marine food web, the smallest organism might be
a.
A.
b.
F.
c.
C.
d.
I.
e.
E.
 

 191. 
For most terrestrial ecosystems, pyramids of numbers, biomass, and energy are essentially the same-they have a broad base and a narrow top. The primary reason for this pattern is that
a.
secondary consumers and top carnivores require less energy than producers.
b.
at each step, energy is lost from the system as a result of keeping the organisms alive.
c.
as matter passes through ecosystems, some of it is lost to the environment.
d.
biomagnification of toxic materials limits the secondary consumers and top carnivores.
e.
top carnivores and secondary consumers have a more general diet than primary producers.
 

 192. 
Which of the following is primarily responsible for limiting the number of trophic levels in most ecosystems?
a.
Many primary and higher-order consumers are opportunistic feeders.
b.
Most predators require large home ranges.
c.
Nutrient cycles involve both abiotic and biotic components of ecosystems.
d.
Nutrient cycling rates tend to be limited by decomposition.
e.
Each energy transfer is less than 100% efficient.
 

 193. 
Which of the following situations is consistent with the green world hypothesis?
a.
Milkweed plants are eaten by monarch caterpillars.
b.
Some gypsy moths cannot feed and thus die because others moths have defoliated the trees in the area.
c.
Webworms cooperate with each other to build a protective silken structure around themselves.
d.
A mild winter improves the survival rate of overwintering cutworms.
e.
Grasshoppers in a corn field are killed by a viral infection.
 

 194. 
Nitrogen is available to plants only in the form of
a.
ammonium.
b.
nitrite.
c.
nitrate.
d.
A and C only
e.
A, B, and C
 

 195. 
In the nitrogen cycle, the bacteria that replenish the atmosphere with N2 are
a.
Rhizobium bacteria.
b.
nitrifying bacteria.
c.
denitrifying bacteria.
d.
methanogenic protozoans.
e.
nitrogen-fixing bacteria.
 

 196. 
How does phosphorus normally enter the atmosphere?
a.
respiration
b.
photosynthesis
c.
rock weathering
d.
geological uplifting (subduction and vulcanism)
e.
It does not enter the atmosphere in biologically significant amounts.
 

 197. 
Which of the following statements is correct about biogeochemical cycling?
a.
The phosphorus cycle involves the rapid recycling of atmospheric phosphorus.
b.
The phosphorus cycle is a sedimentary cycle that involves the weathering of rocks.
c.
The carbon cycle is a localized cycle that primarily reflects the burning of fossil fuels.
d.
The carbon cycle has maintained a constant atmospheric concentration of CO2 for the past million years.
e.
The nitrogen cycle involves movement of nitrogen very little of which is chemically altered by either the biotic or abiotic components of the ecosystem.
 

 198. 
Long-term ecological research at the Hubbard Brook Experimental Forest indicates that
a.
intensive logging can dramatically increase levels of nitrate and calcium ions retained in the soil.
b.
the amount of nutrients leaving an intact forest ecosystem is controlled by the plants themselves.
c.
selective logging can actually increase species richness in temperate forests.
d.
A and C only
e.
A, B, and C
 

 199. 
If you were tracking a nutrient molecule through an ecosystem, which of the following statements would you expect to verify?
a.
Molecules move through all ecosystems at the same constant rate, as the laws of physics would predict.
b.
Because of the liquid nature of the aquatic ecosystem, nutrient molecules move through it rapidly compared with forest ecosystems.
c.
Vertical mixing is essential for high productivity in aquatic ecosystems.
d.
A and B only
e.
A, B, and C
 

 200. 
Which of the following statements is (are) true?
a.
An ecosystem's trophic structure determines the rate at which energy cycles within the system.
b.
At any point in time, it is impossible for consumers to outnumber producers in an ecosystem.
c.
Chemoautotrophic prokaryotes near deep-sea vents are primary producers.
d.
There has been a well-documented increase in atmospheric carbon dioxide over the past several decades.
e.
both C and D
 

 201. 
Human-induced modifications of the nitrogen cycle can result in
a.
eutrophication of freshwater ecosystems.
b.
increased availability of fixed nitrogen to primary producers.
c.
accumulation of toxic levels of nitrates in groundwater.
d.
A and C only
e.
A, B, and C
 

 202. 
The high levels of pesticides found in birds of prey is an example of
a.
eutrophication.
b.
predation.
c.
biological magnification.
d.
the green world hypothesis.
e.
chemical cycling through an ecosystem.
 

 203. 
If the flow of energy in an arctic ecosystem goes through a simple food chain from seaweeds to fish to seals to polar bears, then which of the following is true?
a.
Polar bears can provide more food for people than seals can.
b.
The total energy content of the seaweeds is lower than that of the seals.
c.
Polar bear meat probably contains the highest concentrations of fat-soluble toxins.
d.
Seals are more numerous than fish.
e.
The carnivores can provide more food for people than the herbivores can.
 
 
Use the figure below to answer the following questions. Examine this food web for a particular terrestrial ecosystem. Each letter is a species. The arrows represent energy flow.

nar013-1.jpg
 

 204. 
Which species is autotrophic?
a.
A
b.
B
c.
C
d.
D
e.
E
 

 205. 
A toxic pollutant would probably reach its highest concentration in which species?
a.
A
b.
B
c.
C
d.
D
e.
E
 

 206. 
Excluding the decomposer, biomass would probably be smallest for which species?
a.
A
b.
B
c.
C
d.
D
e.
E
 
 
The following questions refer to the organisms in a grassland ecosystem listed below. Each term may be used once, more than once, or not at all.

A.hawks
B.snakes
C.shrews
D.grasshoppers
E.grass
 

 207. 
an autotroph
a.
A
b.
B
c.
C
d.
D
e.
E
 

 208. 
smallest biomass
a.
A
b.
B
c.
C
d.
D
e.
E
 

 209. 
When levels of CO2 are experimentally increased, C3 plants generally respond with a greater increase in productivity than C4 plants. This is because
a.
C3 plants are more efficient in their use of CO2.
b.
C3 plants are able to obtain the same amount of CO2 by keeping their stomata open for shorter periods of time.
c.
C4 plants don't use CO2 as their source of carbon.
d.
C3 plants are more limited than C3 plants by CO2 availability.
e.
B and D only.
 
 
The following questions refer to the terms below. Each term may be used once, more than once, or not at all.

A.green world hypothesis
B.turnover
C.biological magnification
D.greenhouse effect
E.cultural eutrophication
 

 210. 
CO2 and water vapor re-reflect infrared radiation back toward Earth
a.
A
b.
B
c.
C
d.
D
e.
E
 

 211. 
caused excessively high levels of DDT in fish-eating birds
a.
A
b.
B
c.
C
d.
D
e.
E
 

 212. 
occurs at a high rate for nutrients in tropical rain forests
a.
A
b.
B
c.
C
d.
D
e.
E
 

 213. 
All of the following are likely results of land-clearing operations such as deforestation and agricultural activity except
a.
destruction of plant and animal habitats.
b.
erosion of soil due to increased water runoff.
c.
leaching of minerals from the soil.
d.
rapid eutrophication of streams and lakes.
e.
decreased carbon dioxide in the atmosphere.
 

 214. 
Agricultural lands frequently require nutritional supplementation because
a.
genetically engineered crops require more nutrients.
b.
the nutrients that enter the plants grown on those lands do not return to that soil.
c.
the prairies that comprise good agricultural land tend to be nutrient-poor.
d.
grains raised for feed must be fortified, and thus require additional nutrients.
e.
both A and B
 

 215. 
Estimates of current rates of extinction
a.
indicate that we have reached a state of unstable equilibrium in which speciation and extinction rates are approximately equal.
b.
suggest that one-half of all animal and plant species may be gone by the year 2100.
c.
indicate that rates may be 1,000 times higher than at any other time in the last 100,000 years.
d.
B and C only
e.
A, B, and C
 

 216. 
Extinction is a natural phenomenon. It is estimated that 99% of all species that ever lived are now extinct. Why then do we say that we are now in a biodiversity crisis?
a.
Humans are ethically responsible for protecting endangered species.
b.
Scientists have finally identified most of the species on Earth and are thus able to quantify the number of species becoming extinct.
c.
The current rate of extinction is as much as 1,000 times higher than at any other time in the last 100,000 years.
d.
Humans have greater medical needs than at any other time in history, and many potential medicinal compounds are being lost as plant species become extinct.
e.
Most biodiversity hot spots have been destroyed by recent ecological disasters.
 

 217. 
Which of the following terms includes all of the others?
a.
species diversity
b.
biodiversity
c.
genetic diversity
d.
ecosystem diversity
e.
species richness
 

 218. 
The Nile perch (Lates niloticus) is a good example of a(n)
a.
introduced predator.
b.
endangered endemic.
c.
population sink.
d.
threatened migratory species.
e.
primary consumer.
 

 219. 
In order to better understand the extent of current extinctions, it will be necessary to
a.
monitor atmospheric carbon dioxide levels.
b.
differentiate between plant extinction and animal extinction.
c.
focus on identifying more species of mammals and birds.
d.
identify more of the yet unknown species of organisms on Earth.
e.
use the average extinction rates of vertebrates as a baseline.
 

 220. 
What is the term for a top predator that contributes to the maintenance of species diversity among its animal prey?
a.
keystone species
b.
keystone mutualist
c.
landscape species
d.
primary consumer
e.
tertiary consumer
 

 221. 
E.O. Wilson coined the term ____ for our innate appreciation of wild environments and living organisms.
a.
bioremediation
b.
bioethics
c.
biophilia
d.
biophobia
e.
landscape ecology
 

 222. 
In which ocean would you find the island of Madagascar?
a.
North Atlantic
b.
South Atlantic
c.
Indian
d.
North Pacific
e.
South Pacific
 

 223. 
Suppose you attend a town meeting at which some experts tell the audience that they have performed a cost-benefit analysis of a proposed transit system that would probably reduce overall air pollution and fossil fuel consumption. The analysis, however, reveals that ticket prices will not cover the cost of operating the system when fuel, wages, and equipment are taken into account. As a biologist, you know that if ecosystem services had been included in the analysis the experts might have arrived at a different answer. Why are ecosystem services rarely included in economic analyses?
a.
Their cost is difficult to quantify.
b.
They are not worth much.
c.
People take them for granted.
d.
A and C only
e.
A, B and C
 

 224. 
One level of the biodiversity crisis is the potential loss of ecosystems. The most serious consequence of a likely loss in ecosystem diversity would be the
a.
increase in global warming and thinning of the ozone layer.
b.
loss of ecosystem services on which people depend.
c.
increase in the dominance of edge-adapted species.
d.
loss of source of genetic diversity to preserve endangered species.
e.
loss of species for "bioprospecting."
 

 225. 
Which of the following most directly relates to the current biodiversity crisis?
a.
increased atmospheric carbon dioxide
b.
ozone depletion
c.
overexploitation of species
d.
habitat destruction
e.
zoned reserves
 

 226. 
According to most conservation biologists, the single greatest threat to global biodiversity is
a.
chemical pollution of water and air.
b.
stratospheric ozone depletion.
c.
insufficient recycling programs for nonrenewable resources.
d.
alteration or destruction of the physical habitat.
e.
global climate change resulting from a variety of human activities.
 

 227. 
Which of the following statements is false?
a.
Within the contiguous United States, more than 50% of wetlands have been drained since the arrival of the first European settlers.
b.
In Central America and Mexico, approximately 98% of tropical dry forests have been cleared.
c.
Given current trends, we can expect at least 20% of the biosphere eventually to be protected in nature reserves.
d.
Of the southern Wisconsin prairie that greeted early settlers, less than 0.1% remains.
e.
The United States contains over 50,000 introduced species.
 

 228. 
How is habitat fragmentation related to extinction?
a.
Less carbon dioxide is absorbed by plants.
b.
More soil is subject to erosion.
c.
Populations of organisms in fragments are smaller and, thus, more susceptible to extinction.
d.
Animals are forced out of habitat fragments.
e.
Fragments generate silt that negatively affects drainages.
 

 229. 
Which of the following is not an example of an introduced species?
a.
brown tree snakes in Guam
b.
timber wolves in Minnesota
c.
zebra mussels in the Great Lakes
d.
kudzu plants in the southern United States
e.
starlings in New York
 

 230. 
Introduced species
a.
are a problem because they can prey on or outcompete native species.
b.
are sometimes present as a result of attempts at biological control.
c.
are sometimes accidentally transported to new environments.
d.
A and B only
e.
A, B, and C
 

 231. 
How might the extinction of some Pacific island bats called "flying foxes" threaten survival of over 75% of the tree species in those islands?
a.
The bats eat the insects that harm competitor plants.
b.
The bats eat fruit that is part of the trees' reproductive cycles.
c.
The bats roost in the trees and fertilize soil around the trees.
d.
The bats pollinate the trees and disperse seeds.
e.
The bats pierce the fruit, which allows the seeds to germinate.
 

 232. 
Which of the following does not represent a potential threat to biodiversity?
a.
importing a European insect into the United States to control an undesirable weed
b.
building a new mall on a previously unoccupied piece of midwestern prairie
c.
letting previously used farmland go fallow and begin to fill with weeds and shrubs
d.
harvesting all of the oysters from an oyster bed off the Atlantic coast
e.
shooting wolves because they pose a threat to ranch cattle
 

 233. 
According to the small-population approach, what would be the best strategy for saving a population that is in an extinction vortex?
a.
determining the minimum viable population size by taking into account the effective population size
b.
establishing a nature reserve to protect its habitat
c.
introducing individuals from other populations to increase genetic variation
d.
determining and remedying the cause of its decline
e.
reducing the population size of its predators and competitors
 

 234. 
One chief area of concern among biologists who use the small-population approach is
a.
intraspecific competition.
b.
sexual selection.
c.
genetic diversity.
d.
runaway selection.
e.
both A and D
 

 235. 
Which of the following is a method of predicting the likelihood that a species will persist in a particular environment?
a.
source-sink analysis
b.
population viability analysis
c.
minimum viable population size
d.
A and C only
e.
A, B, and C
 

 236. 
Review the formula for effective population size. Imagine a population of 1,000 small rodents. Of these, 300 are breeding females, 300 are breeding males, and 400 are nonbreeding juveniles. What is the effective population size?
a.
1,000
b.
1,200
c.
600
d.
400
e.
300
 

 237. 
Which of the following statements related to genetic variation is true?
a.
Genetic variation does not contribute to biodiversity.
b.
Population size is always positively correlated with genetic variation.
c.
Populations with low Ne are relatively susceptible to effects of bottlenecking and genetic drift.
d.
Recent increases in population size of the northern sea elephant are probably related to high levels of genetic variation.
e.
Cord grass populations that live in salt marshes require great genetic variation to thrive.
 

 238. 
Which of the following life history traits can potentially influence effective population size (Ne)?
a.
maturation age
b.
genetic relatedness among individuals in a population
c.
family size
d.
A and B only
e.
A, B, and C
 

 239. 
Modern conservation science increasingly aims at
a.
protecting federally listed endangered species.
b.
lobbying for strict enforcement of the U.S. Endangered Species Act.
c.
sustaining biodiversity of entire ecosystems and communities.
d.
maintaining all genetic diversity within all species.
e.
both A and B
 

 240. 
Which of the following statements is correct about landscape ecology?
a.
It is the application of ecological principles to the design and construction of sustainable lawns and gardens.
b.
It is the application of ecological principles to land-use planning.
c.
It focuses primarily on human-altered ecological systems.
d.
It deals primarily with ecosystems in urban settings.
e.
It deals with the study of the home ranges of various animals.
 

 241. 
Which of the following statements is false?
a.
Edges become more extensive with increased forest fragmentation.
b.
Edges are features of human-altered habitats only.
c.
Edges frequently have their own biological communities.
d.
The proliferation of edge species can have a positive or negative effect on biodiversity.
e.
The interface between a forest and an adjoining field would be considered an edge.
 

 242. 
Which of the following statements about movement corridors is true?
a.
Corridors can be either strips or a series of clumps of quality habitat.
b.
Corridors can be natural or constructed by humans.
c.
Riparian habitats frequently serve as effective corridors.
d.
A and C only
e.
A, B, and C
 

 243. 
Wildlife movement corridors can
a.
promote gene flow.
b.
promote disease transmission.
c.
assist migratory species.
d.
A and C only
e.
A, B, and C
 

 244. 
Relatively small geographic areas with high concentrations of endemic species are known as
a.
endemic sinks.
b.
critical communities.
c.
biodiversity hot spots.
d.
endemic metapopulations.
e.
bottlenecks.
 

 245. 
Which of the following is (are) true? Biodiversity hot spots for plants
a.
have high concentrations of endemic species.
b.
have large numbers of endangered and threatened species.
c.
can be underwater.
d.
make up a total of only 1.5% of the global land surface.
e.
All of the above are true.
 

 246. 
Biodiversity hot spots are recognized on the basis of
a.
their proximity to national parks and reserves.
b.
the number of endemic species they contain
c.
the degree to which the included species are threatened with extinction.
d.
B and C only
e.
A, B, and C
 

 247. 
The term "biotic boundary" refers to the
a.
area that an animal defends as its territory.
b.
area needed to sustain a population.
c.
home range of an animal.
d.
distribution of an organism.
e.
area where a species evolved.
 

 248. 
Which of the following statements about protected areas is not correct?
a.
Despite repeated efforts, zoned reserves are usually a failure.
b.
National parks are only one type of protected area.
c.
Most protected areas are small in size.
d.
Protected area management must be coordinated with management of lands outside the protected zone.
e.
Biodiversity hot spots are important areas to protect.
 

 249. 
Human use of prokaryotic organisms to help detoxify a polluted wetland would be an example of
a.
ecosystem augmentation.
b.
keystone species introduction.
c.
biological control.
d.
bioremediation.
e.
population viability analysis.
 

 250. 
Which of the following is (are) related to the agenda of the Sustainable Biosphere Initiative?
a.
defining what ecological studies are needed for conserving Earth's resources
b.
maintaining productivity of human-made as well as natural ecosystems
c.
understanding interactions between climate and ecological dynamics
d.
resource management and development
e.
all of the above
 



 
Check Your Work     Start Over