1) Which of the following statements is consistent with the principle of competitive exclusion?
D) Even a slight reproductive advantage will eventually lead to the elimination of the less well adapted of two competing species.
2) According to the competitive exclusion principle, two species cannot continue to occupy the same
B) niche.
3) Which of the following best describes resource partitioning?
B) slight variations in niche that allow similar species to coexist
4) 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. However, where their ranges overlap, the two-spot avenger beetle hunts at night and the three-spot hunts in the morning. When you bring them into the laboratory and isolate the two different species, you discover that the offspring of both species are found to be nocturnal. You have discovered an example of
E) resource partitioning.
5) Resource partitioning would be most likely to occur between
B) sympatric populations of species with similar ecological niches.
6) Which of the following is an example of cryptic coloration?
E) a "walking stick" insect that resembles a twig
7) Which of the following is an example of Müllerian mimicry?
A) two species of unpalatable butterfly that have the same color pattern
8) Which of the following is an example of Batesian mimicry?
C) a nonvenomous snake that looks like a venomous snake
9) Which of the following is an example of aposematic coloration?
A) stripes of a skunk
10) Dwarf mistletoes are flowering plants that grow on certain forest trees. They obtain nutrients and water from the vascular tissues of the trees. The trees derive no known benefits from the dwarf mistletoes. Which of the following best describes the interactions between dwarf mistletoes and trees?
B) parasitism
11) Evidence shows that some grasses benefit from being grazed. Which of the following terms would best describe this plant-herbivore interaction?
A) mutualism
12) Which of the following would be most significant in understanding the structure of an ecological community?
E) determining how many species are present overall, which particular species are present, the kinds of interactions that occur among organisms of different species, and the relative abundance of species
13) Which of the following studies would a community ecologist undertake to learn about competitive interactions?
E) selectivity of nest sites among cavity-nesting songbirds, the grass species preferred by grazing pronghorn antelope and bison, nitrate and phosphate uptake by various hardwood forest tree species, and stomach analysis of brown trout and brook trout in streams where they coexist
14) White-breasted nuthatches and Downy woodpeckers both eat insects that hide in the furrows of bark in hardwood trees. The Downy woodpecker searches for insects by hunting from the bottom of the tree trunk to the top, whereas the white-breasted nuthatch searches from the top of the trunk down. These hunting behaviors best illustrate which of the following ecological concepts?
B) resource partitioning
15) Monarch butterflies are protected from birds and other predators because of cardiac glycosides they incorporate into their tissues from eating milkweed when they were in their caterpillar stage. The wings of a different species of butterfly, the Viceroy, look nearly identical to the Monarch so predators that have learned not to eat the bad-tasting Monarch avoid Viceroys as well. This example best describes
C) Batesian mimicry.
16) Prairie dogs once covered the expanses of the Great Plains. Their grazing made the grass more nutritious for the huge herds of bison, and they were preyed upon by a variety of snakes, raptors, and mammals. In fact, the black-footed ferret (now endangered) specialized in prairie dog predation. Today, increases in housing and agricultural developments have eradicated many prairie dog towns. Which of the following statements about prairie dogs is true?
E) Their fundamental niche has expanded.
17) Which statement best describes the evolutionary significance of mutualism?
C) Interaction increases the survival and reproductive rates of mutualistic species.
18) How might an ecologist test whether a species is occupying its realized or its fundamental niche?
E) Remove a competitor species to see if the species expands its range.
19) What percent of all species on Earth are parasites?
D) 33 1/3%
20) Which of the following terms is used by ecologists to describe the community interaction where one organism makes the environment more suitable for another organism?
D) facilitation
21) How did Eugene Odum describe an ecological niche?
C) an organism's "profession" in the community
22) Approximately how many kg of carnivore biomass can be supported by a field plot containing 1,000 kg of plant material?
D) 10
23) The energetic hypothesis and dynamic stability hypothesis are ideas that attempt to explain
B) the length of food chains.
24) In a tide pool, 15 species of invertebrates were reduced to eight after one species was removed. The species removed was likely a(n)
B) keystone species.
25) Elephants are not the most dominant species in African grasslands, yet they influence community structure. 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. Which of the following describes why elephants are the keystone species in this scenario?
A) Essentially all of the other species depend on the presence of the elephants to maintain the community.
26) According to bottom-up and top-down control models of community organization, which of the following expressions would imply that an increase in the size of a carnivore (C) population would negatively impact on its prey (P) population, but not vice versa?
A) P ← C
27) Which of the following is the most accepted hypothesis as to why invasive species take over communities into which they have been introduced?
B) Invasive species are not held in check by the predators and agents of disease that have always been in place for the native species.
28) Biomanipulation can best be described as
A) removing many of the next higher trophic level organisms so that the struggling trophic level below can recover.
29) Imagine five forest communities, each with 100 individuals distributed among four different tree species (W, X, Y, and Z). Which forest community would be most diverse?
A) 25W, 25X, 25Y, 25Z
30) Why are food chains relatively short?
C) Longer chains are less stable and energy transfer between levels is inefficient.
31) Which term do ecologists use to describe the ability of a community either to resist change or to recover to its original state after change?
A) stability
32) According to the nonequilibrium model,
E) communities are constantly changing after being influenced by disturbances.
33) 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
D) inhibition.
34) The 1988 Yellowstone National Park lodgepole pine forest fires were likely the result of
C) years of fire suppression by humans.
35) Why do moderate levels of disturbance result in an increase in community diversity?
A) Habitats are opened up for less competitive species.
36) Species richness increases
B) as we travel southward from the North Pole.
37) There are more species in tropical areas than in places more distant from the equator. This is probably a result of
B) more intense annual solar radiation.
38) A community's actual evapotranspiration is a reflection of
A) solar radiation, temperature, and water availability.
39) Why do tropical communities tend to have greater species diversity than temperate or polar communities?
D) Tropical communities are generally older than temperate and polar communities.
40) Which of the following is a correct statement about the McArthur/Wilson Island Equilibrium Model?
D) Small islands receive few new immigrant species.
41) Which of the following best describes the consequences of white-band disease in Caribbean coral reefs?
C) Algal species take the place of the dead coral, and the fish community is dominated by herbivores.
42) Zoonotic disease
B) is caused by pathogens that are transferred from other animals to humans by direct contact or by means of a vector.
43) Of the following zoonotic diseases, which is most likely to be studied by a community ecologist?
D) avian flu
44) Which of the following studies would shed light on the mechanism of spread of H5N1 from Asia?
A) Perform cloacal or saliva smears of migrating waterfowl to monitor whether any infected birds show up in Alaska.
45) Why is a pathogen generally more virulent in a new habitat?
D) Hosts in new environments have not had a chance to become resistant to the pathogen through natural selection.
46) In terms of community ecology, why are pathogens more virulent now than ever before?
C) Human activities are transporting pathogens globally at an unprecedented rate.
47) The oak tree pathogen, Phytophthora ramorum, has migrated 650 km in 10 years. West Nile virus spread from New York State to 46 other states in 5 years. The difference in the rate of spread is probably related to
B) the mobility of their hosts.
48) During the course of the formation of a parasite/host relationship, a critical first step in this evolution would be
C) deriving nourishment without killing the host.
49) Which of the following statements is a valid conclusion of this experiment?
D) When Balanus is removed, it can be observed that the realized niche of Chthamalus is smaller than its fundamental niche.
50) Connell conducted this experiment to learn more about
E) competitive exclusion and distribution of barnacle species.
51) According to the Shannon Diversity Index, which block would show the greatest diversity?
E) 5
52) Which letter represents an organism that could be a carnivore?
E) E
53) Which letter represents an organism that could be a producer?
B) B
54) Which letter represents an organism that could be a primary consumer?
C) C
55) Which island would likely have the greatest species diversity?
A) A
56) Which island would likely exhibit the most impoverished species diversity?
C) C
57) Which island would likely have the lowest extinction rate?
A) A
58) In McDonaldland, which of the following would be an example of an introduced species?
C) BK Whopper
59) Which of the following would be considered a keystone species in McDonaldland?
A) Big Mac
60) Which two "species" are likely to compete for the same ecological niche?
E) No two species can ever occupy the same ecological niche.
61) According to the McDonaldland scenario, which of the following would best define an ecological community?
B) the entire menu at McDonaldland
62) In a two-week marketing analysis, McDonald's was interested in finding out the popularity of the Big Mac. Using the realized/fundamental niche concept of community ecology, what should the marketing researchers do?
C) Remove the Quarter Pounder from the menu and see if Big Mac sales increase.
63) What interactions exist between a "carrier crab" and "sea urchin hitch-hiker"?
A) +/+
64) What interactions exist between the cattle egret and grazing cattle?
B) +/o
65) What interactions exist between a lion pride and a hyena pack?
E) -/-
66) What interactions exist between a bee and a flower?
A) +/+
67) What interactions exist between a tick on a dog and the dog?
C) +/-
68) What interactions exist between cellulose-digesting organisms in the gut of a termite and the termite?
A) +/+
69) What interactions exist between mycorrhizae and evergreen tree roots?
A) +/+
70) The feeding relationships among the species in a community determine the community's
E) trophic structure.
71) The principle of competitive exclusion states that
D) two species that have exactly the same niche cannot coexist in a community.
72) Based on the intermediate disturbance hypothesis, a community's species diversity is increased by
C) moderate levels of disturbance.
73) According to the equilibrium model of island biogeography, species richness would be greatest on an island that is
A) large and close to a mainland.
74) Keystone predators can maintain species diversity in a community if they
B) prey on the community's dominant species.
75) Food chains are sometimes short because
C) most of the energy in a trophic level is lost as it passes to the next higher level.
76) Which of the following could qualify as a top-down control on a grassland community?
D) effect of grazing intensity by bison on plant species diversity
77) The most plausible hypothesis to explain why species richness is higher in tropical than in temperate regions is that
B) tropical regions generally have more available water and higher levels of solar radiation.
1) "How do seed-eating animals affect the distribution and abundance of the trees?" This question
E) All options are correct.
2) Which of the following levels of ecological organization is arranged in the correct sequence from most to least inclusive?
B) ecosystem, community, population, individual
3) Which of the following examples of an ecological effect leading to an evolutionary effect is most correct?
C) A few individuals with denser fur survive the coldest days of an ice age, and the reproducing survivors of the ice age all have long fur.
4) Which of the following might be an investigation of microclimate?
D) the effect of sunlight intensity on species composition in a decaying rat carcass
5) Which of the following choices includes all of the others in creating global terrestrial climates?
A) differential heating of Earth's surface
6) Why is the climate drier on the leeward side of mountain ranges that are subjected to prevailing winds?
C) Pushed by the prevailing winds on the windward side, air is forced to rise, cool, condense, and drop its precipitation, leaving only dry air to descend the leeward side.
7) What would be the effect on climate in the temperature latitudes if Earth were to slow its rate of rotation from a 24-hour period of rotation to a 48-hour period of rotation?
E) The climate would stay the same. The only change would be longer days and nights.
8) Palm trees and subtropical plants are commonplace in Land's End, England, whose latitude is the equivalent of Labrador in coastal Canada where the local flora is subarctic. Which statement best explains why this apparent anomaly exists between North America and Europe?
B) Warm ocean currents interact with England, whereas cold ocean currents interact with Labrador.
9) Which statement describes how climate might change if Earth was 75% land and 25% water?
B) Earth's daytime temperatures would be higher and nighttime temperatures lower.
10) Which of the following abiotic factors has the greatest influence on the metabolic rates of plants and animals?
C) temperature
11) In mountainous areas of western North America, north-facing slopes would be expected to
E) support biological communities similar to those found at higher elevations on similar south-facing slopes.
12) Deserts typically occur in a band at 20 degrees north and south latitude because
A) descending air masses tend to be cool and dry.
13) 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 to 33 1/2 degrees?
A) Summers and winters in the United States would likely become warmer and colder, respectively.
14) 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
E) the elimination of seasonal variation.
15) The main reason polar regions are cooler than the equator is that
B) sunlight strikes the poles at a lower angle.
16) Which of the following environmental features might influence microclimates?
E) All of the options are correct.
17) The success with which plants extend their range northward following glacial retreat is best determined by
C) their seed dispersal rate.
18) As climate changes because of global warming, species' ranges in the northern hemisphere may move northward, using effective reproductive adaptations to disperse their seeds. The trees that are most likely to avoid extinction in such an environment are those that
A) have seeds that are easily dispersed by wind or animals.
19) Generalized global air circulation and precipitation patterns are caused by
A) rising, warm, moist air masses that cool and release precipitation as they rise and then, at high altitude, cool and sink back to the surface as dry air masses after moving north or south of the tropics.
20) Air masses formed over the Pacific Ocean are moved by prevailing westerlies where they encounter extensive north-south mountain ranges, such as the Sierra Nevada and the Cascades. Which statement best describes the outcome of this encounter between a landform and an air mass?
B) The warm, moist Pacific air rises and cools, releasing precipitation as it moves up the windward side of the range, and this cool, now dry air mass heats up as it descends on the leeward side of the range.
21) If global warming continues at its present rate, which biomes will likely take the place of the coniferous forest (taiga)?
B) temperate broadleaf forest and grassland
22) Which of the following are important biotic factors that can affect the structure and organization of biological communities?
C) predation, competition
23) Which of the following can be said about light in aquatic environments?
A) Water selectively reflects and absorbs certain wavelengths of light.
24) 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?
D) ocean currents
25) Which of the following investigations would shed the most light on the distribution of organisms in temperate regions that are faced with climate change?
B) Look back at the changes that occurred since the Ice Age and how species redistributed as glaciers melted, then make predictions on future distribution in species based on past trends.
26) Which series is correctly layered from top to bottom in a tropical rain forest?
D) emergent layer, canopy, under story, shrub/immature layer, ground layer
27) What is the limiting factor for the growth of trees in the tundra?
E) permafrost
28) Generally speaking, deserts are located in places where air masses are usually
D) descending.
29) Turnover of water in temperate lakes during the spring and fall is made possible by which of the following?
D) the changes in the density of water as seasonal temperatures change
30) In temperate lakes, the surface water is replenished with nutrients during turnovers that occur in the
A) autumn and spring.
31) Which of the following is responsible for the differences in summer and winter temperature stratification of deep temperate zone lakes?
A) Water is densest at 4°C.
32) Imagine that a deep temperate zone lake did not "turn over" during the spring and fall seasons. Based on the physical and biological properties of limnetic ecosystems, what would be the difference from normal seasonal turnover?
D) Lakes would suffer a nutrient depletion in surface layers.
33) Which marine zone would have the lowest rates of primary productivity (photosynthesis)?
B) abyssal
34) If you are interested in observing a relatively simple community structure in a clear water lake, you would do well to choose diving into
A) an oligotrophic lake.
35) Which of the following statements about the ocean pelagic biome is true?
D) Pelagic ocean photosynthetic activity is disproportionately low in relation to the size of the biome.
36) 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, which of the following marine communities most likely would be least affected?
A) deep-sea vent
37) Which of the examples below provides appropriate abiotic and biotic factors that might determine the distribution of the species in question?
B) the number of frost-free days, and competition between species of introduced grasses and native alpine grasses
38) A certain species of pine tree survives only in scattered locations at elevations above 2,800 m in the western United States. To understand why this tree grows only in these specific places, an ecologist should
C) investigate the various biotic and abiotic factors that are unique to high altitude.
39) Species introduced by humans to new geographic locations
D) can outcompete and displace native species for biotic and abiotic resources.
40) Which of the following statements best describes the effect of climate on biome distribution?
C) Not only is the average climate important in determining biome distribution but so is the pattern of climatic variation.
41) In the development of terrestrial biomes, which factor is most dependent on all the others?
A) the species of colonizing animals
42) 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
B) convergent evolution.
43) In which of the following terrestrial biome pairs are both parts dependent upon periodic burning?
B) chaparral and savanna
44) Fire suppression by humans
B) can change the species composition within biological communities.
45) Which of the following statements best describes the interaction between fire and ecosystems?
B) Many kinds of plants and plant communities have adapted to frequent fires.
46) In which community would organisms most likely have adaptations enabling them to respond to different photoperiods?
D) temperate forest
47) The growing season would generally be shortest in which of the following biomes?
E) coniferous forest
48) Trees are not usually found in the tundra biome because of
E) permafrost.
49) Studying species transplants is a way that ecologists
D) determine if dispersal is a key factor in limiting distribution of organisms.
50) Which climograph shows the climate for location 1?
A) A
51) Which climograph shows the climate for location 2?
D) F
52) Which climograph shows the climate for location 3?
C) D
53) Which climograph shows the climate for location 4?
D) E
54) Which climograph shows the climate for location 5?
B) C
55) Which of the following best substantiates why location 3 is an equatorial (tropical) climate?
C) The temperature is high for each monthly average.
56) Which zone has a condition of constant temperature?
C) C
57) Which zone produces the most global oxygen gas?
B) B
58) Which zone is comprised largely of detritus-feeding organisms?
C) C
59) Which zone has the lowest biomass per unit of area?
D) D
60) Which zone experiences the most abiotic change over a 24-hour period?
A) A
61) How would an ecologist likely explain the expansion of the cattle egret?
D) A habitat left unoccupied by native herons and egrets met the biotic and abiotic requirements of the cattle egret transplants and their descendants.
62) This observation best illustrates which of the following principles about factors that limit distribution of organisms?
C) Environmental factors are limiting not only in amount but also in longevity.
63) What might be the adaptive significance of these unusual forests growing the way they do in this marginal habitat?
C) Taproot formation is impossible, so trees developed shallow root beds.
64) Which of the following areas of study focuses on the exchange of energy, organisms, and materials between ecosystems?
C) landscape ecology
65) Which lake zone would be absent in a very shallow lake?
B) aphotic zone
66) Which of the following is true with respect to oligotrophic lakes and eutrophic lakes?
D) Eutrophic lakes are richer in nutrients.
67) Which of the following biomes is correctly paired with the description of its climate?
E) tropical forests–nearly constant day length and temperature
68) Which of the following is characteristic of most terrestrial biomes?
D) vegetation demonstrating vertical layering
69) The oceans affect the biosphere in all of the following ways except
D) regulating the pH of freshwater biomes and terrestrial groundwater.
70) Which statement about dispersal is false?
C) Dispersal occurs only on an evolutionary time scale.
71) When climbing a mountain, we can observe transitions in biological communities that are analogous to the changes
A) in biomes at different latitudes.
72) Suppose that the number of bird species is determined mainly by the number of vertical strata found in the environment. If so, in which of the following biomes would you find the greatest number of bird species?
A) tropical rain forest
73) If the direction of Earth's rotation reversed, the most predictable effect would be
C) winds blowing from west to east along the equator.
1) Population ecologists are primarily interested in
B) understanding how biotic and abiotic factors influence the density, distribution, size, and age structure of populations.
2) A population is correctly defined as having which of the following characteristics?
C) I and II only
3) An ecologist recorded 12 white-tailed deer, Odocoileus virginianus, per square mile in one woodlot and 20 per square mile in another woodlot. What was the ecologist comparing?
A) density
4) During the spring, you are studying the mice that live in a field near your home. The population density is high, but you realize that you rarely observe any reproductive female mice. This most likely indicates
D) that you are observing immigrant mice.
5) Uniform spacing patterns in plants such as the creosote bush are most often associated with
D) competitive interaction between individuals of the same population.
6) Which of the following groups would be most likely to exhibit uniform dispersion?
A) red squirrels, who actively defend territories
7) To construct a reproductive table for a sexual species, one needs to
C) keep track of the females in a cohort.
8) Which of the following examples would most accurately measure the density of the population being studied?
E) counting the number of zebras from airplane census observations.
9) Which of the following assumptions have to be made regarding the capture-recapture estimate of population size?
E) I, II, and III
10) Long-term studies of Belding's ground squirrels show that immigrants move nearly 2 km from where they are born and become 1%-8% of the males and 0.7%-6% of the females in other populations. On an evolutionary scale, why is this significant?
C) These immigrants provide a source of genetic diversity for the other populations.
11) Which of the following sets of measurements is the most useful when studying populations?
A) density, dispersion, and demographics of a population
12) Which of the following scenarios would provide the most legitimate data on population density?
B) Count the number of pine trees in several randomly selected 10 m x 10 m plots and extrapolate this number to the fraction of the study area these plots represent.
13) Which of the following is the best example of uniform distribution?
C) territorial songbirds in a mature forest during mating season
14) Which of the following choices would most likely promote random distribution?
E) homogeneous chemical and physical factors in the environment
15) Which of the following best defines a cohort?
D) a group of the individuals from the same age group, from birth until they are all dead
16) Why do some invertebrates, such as lobsters, show a "stair-step" survivorship curve?
C) Many invertebrates molt in order to grow, and they are vulnerable to predation during their "soft shell" stage.
17) Which of the following is the most important assumption for the capture-recapture method to estimate the size of wildlife populations?
E) Marked individuals have the same probability of being recaptured as unmarked individuals during the recapture phase.
18) 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. Calculate an estimate of the number of individuals added to (or lost from) a population of 1,000 individuals in one year.
B) 40 individuals added
19) Exponential growth of a population is represented by dN/dt =
B. SEE IMAGE
20) Starting from a single individual, what is the size of a population of bacteria that reproduce by binary fission every 20 minutes at the end of a 2-hour time period? (Assume unlimited resources and no mortality.)
D) 512
21) Which of the following is the equation for zero population growth (ZPG)?
A) R = b - m
22) In July 2008, the United States had a population of approximately 302,000,000 people. How many Americans were there in July 2009, if the estimated 2008 growth rate was 0.88%?
D) 304,000,000
23) In 2008, the population of New Zealand was approximately 4,275,000 people. If the birth rate was 14 births for every 1,000 people, approximately how many births occurred in New Zealand in 2008?
C) 60,000
24) Consider two forests: one is an undisturbed old-growth forest, while the other has recently been logged. In which forest are species likely to experience exponential growth, and why?
C) Logged, because the disturbed forest affords more resources for increased specific populations to grow.
25) Logistic growth of a population is represented by dN/dt =
D. SEE IMAGE
26) As N approaches K for a certain population, which of the following is predicted by the logistic equation?
B) The growth rate will approach zero.
58) Which of the following is a conclusion that can be drawn from this graph?
D) There appears to be a negative correlation between brood enlargements and parental survival.
28) The Allee effect is used to describe a population that
A) has become so small that it will have difficulty surviving and reproducing.
29) Carrying capacity is
B) the maximum population size that a particular environment can support.
30) Which of the following causes populations to shift most quickly from an exponential to a logistic population growth?
D) competition for resources
31) Which of the following statements about the evolution of life histories is correct?
C) Most populations have both r- and K-selected characteristics that vary under different environmental conditions.
32) Natural selection involves energetic trade-offs between
E) high survival rates of offspring and the cost of parental care.
33) The three basic variables that make up the life history of an organism are
C) age when reproduction begins, how often reproduction occurs, and how many offspring are produced per reproductive episode.
34) Which of the following pairs of reproductive strategies is consistent with energetic trade-off and reproductive success?
B) Female rabbits that suffer high predation rates may produce several litters per breeding season, and coconuts produce few fruits, but most survive when they encounter proper growing conditions.
35) Pacific salmon and annual plants are excellent examples of
E) semelparous reproduction.
36) Which of the following is characteristic of K-selected populations?
A) offspring with good chances of survival
37) Which variables define the ecological life history of a species?
A) the age at which reproduction begins, frequency of reproduction, and the number of offspring for each reproductive episode
38) Which pattern of reproduction is correctly paired with a species?
B) iteroparityelephant
39) Often the growth cycle of one population has an effect on the cycle of another. As moose populations increase, for example, wolf populations also increase. Thus, if we are considering the logistic equation for the wolf population,
D) K
40) In which of the following situations would you expect to find the largest number of K-selected individuals?
C) the flora and fauna of a coral reef in the Caribbean
41) Which of the following is most likely to contribute to density-dependent regulation of populations?
B) intraspecific competition for nutrients
42) Why do populations grow more slowly as they approach their carrying capacity?
A) Density-dependent factors lead to fewer births and increased mortality.
43) A population of white-footed mice becomes severely overpopulated in a habitat that has been disturbed by human activity. Sometimes intrinsic factors cause the population to increase in mortality and lower reproduction rates to occur in reaction to the stress of overpopulation. Which of the following is an example of intrinsic population control?
B) Females undergo hormonal changes that delay sexual maturation and many individuals suffer depressed immune systems and die due to the stress of overpopulation.
44) Why is territoriality an adaptive behavior for songbirds maintaining populations at or near their carrying capacity?
C) Songbird males defend territories commensurate with the size from which they can derive adequate resources for themselves, their mate, and their chicks.
45) Which of the following could be a density-independent factor limiting human population growth?
B) earthquakes
46) An ecological footprint is a construct that is useful
A) for a person living in a developed nation to consider to make better choices when using global food and energy resources.
47) Which of the following was the most significant limiting factor in human population growth in the 20th century?
E) clean water
48) Which of the following is most key to understanding the demographic transition in human population growth?
C) voluntary reduction of family size
49) Why does the 2009 U.S. population continue to grow even though the United States has essentially established a ZPG?
B) immigration
50) Which statement is true with regard to human population growth?
C) Its rate of growth is slowing.
51) Which curve best describes survivorship in marine molluscs?
E) E
52) Which curve best describes survivorship in elephants?
A) A
53) Which curve best describes survivorship in a marine crustacean that molts?
D) D
54) Which curve best describes survivorship in humans who live in undeveloped nations?
A) A
55) Which statement best explains survivorship curve B?
E) Survivorship can only decrease; therefore, this curve could not happen in nature.
56) Which of the following graphs illustrates the population growth curve of single bacterium growing in a flask of ideal medium at optimum temperature over a 24-hour period?
C. SEE IMAGE
57) Which of the following graphs illustrates the growth curve of a small population of rodents that has grown to reach a static carrying capacity?
Answer: E
58) Which of the following is a conclusion that can be drawn from this graph?
D) There appears to be a negative correlation between brood enlargements and parental survival.
59) Which of the following is a likely graphic outcome of a population of deer introduced to an island with an adequate herbivory and without natural predators, parasites, or disease?
A. SEE IMAGE
60) Which of the following graphs illustrates the growth over several seasons of a population of snowshoe hares that were introduced to an appropriate habitat also inhabited by predators in northern Canada?
Answer: D
61) Which population(s) is (are) in the process of decreasing?
B) II
62) Which population(s) appear(s) to be stable?
C) III
63) Assuming these age-structure diagrams describe human populations, in which population is unemployment likely to be a societal issue in the future?
A) I
64) Assuming these age-structure diagrams describe human populations, which population(s) is (are) likely to experience zero population growth (ZPG)?
C) III
65) What is a logical conclusion that can be drawn from the graphs above?
C) Developed countries have lower infant mortality rates and higher life expectancy than developing countries.
66) In terms of demographics, which country is likely to experience the greatest population growth problem over the next ten years?
E) Afghanistan, with a 3.85 annual growth rate
67) To measure the population of lake trout in a 250-hectare lake, 400 individual trout were netted and marked with a fin clip, then returned to the lake. The next week, the lake was netted again, and out of the 200 lake trout that were caught, 50 had fin clips. Using the capture-recapture estimate, the lake trout population size could be closest to which of the following?
D) 1,600
68) 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 why because he used to catch 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 somewhat fewer 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 and intrinsic characteristics of population growth
69) Imagine that you are managing a large game ranch. You know from historical accounts that a species of deer used to live there, but they have been extirpated. You decide to reintroduce them. After doing some research to determine what might be an appropriately sized founding population, you do so. You then watch the population increase for several generations, and graph the number of individuals (vertical axis) against the number of generations (horizontal axis). The graph will likely appear as
D) a "J," increasing with each generation.
70) Population ecologists follow the fate of same-age cohorts to
B) determine the birth rate and death rate of each group in a population.
71) A population's carrying capacity
A) may change as environmental conditions change.
72) Scientific study of the population cycles of the snowshoe hare and its predator, the lynx, has revealed that
C) multiple biotic and abiotic factors contribute to the cycling of the hare and lynx populations.
73) Based on current growth rates, Earth's human population in 2012 will be closest to
D) 7 billion.
74) A recent study of ecological footprints concluded that
E) the ecological footprint of the United States is large because per capita resource use is high.
75) The observation that members of a population are uniformly distributed suggests that
C) the members of the population are competing for access to a resource.
76) According to the logistic growth equation
C) population growth is zero when N equals K.
77) Which pair of terms most accurately describes life history traits for a stable population of wolves?
D) iteroparous; K-selected
78) During exponential growth, a population always
B) grows at its maximum per capita rate.
79) Which of the following statements about human population in industrialized countries is incorrect?
A) Life history is r-selected.