55, 54, 56, 52, 53

19) Exponential growth of a population is represented by dN/dt = A) B) rN C) rN (K + N) D) rN E) rN

B

45) Which of the following could be a density-independent factor limiting human population growth? A) social pressure for birth control B) earthquakes C) plagues D) famines E) pollution

B

49) Why does the 2009 U.S. population continue to grow even though the United States has essentially established a ZPG? A) emigration B) immigration C) better sanitation D) baby boomer reproduction E) the 2007-2009 economic recession

B

12) We should care about loss in biodiversity in the populations of other species because of A) biophilia. B) potential loss of medicines and other products yet undiscovered from threatened species. C) potential loss of genes, some of which may code for proteins useful to humans. D) the risk to global ecological stability. E) All of the options are correct.

E

74) A recent study of ecological footprints concluded that A) Earth's carrying capacity for humans is about 10 billion. B) Earth's carrying capacity would increase if per capita meat consumption increased. C) current demand by industrialized countries for resources is much smaller than the ecological footprint of those countries. D) it is not possible for technological improvements to increase Earth's carrying capacity for humans. E) the ecological footprint of the United States is large because per capita resource use is high.

E

8) Which of the following examples would most accurately measure the density of the population being studied? A) counting the number of prairie dog burrows per hectare B) counting the number of times a 1 kilometer transect is intersected by tracks of red squirrels after a snowfall C) counting the number of coyote droppings per hectare D) multiplying the number of moss plants counted in 10 quadrats of 1m2 each by 100 to determine the density per kilometer2. E) counting the number of zebras from airplane census observations.

E

Figure 54.4 55) Which island would likely have the greatest species diversity? A) A B) B C) C D) D E) E

: A

25) Logistic growth of a population is represented by dN/dt = A) B) rN C) rN (K + N) D) rN E) rN

D

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. B) large and remote. C) small and remote. D) small and close to a mainland. E) environmentally homogeneous.

: A

11) 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

: A

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. B) Grazing animals depend upon the elephants to convert forests to grassland. C) Elephants prevent drought in African grasslands. D) Elephants are the biggest herbivore in this community. E) Elephants help other populations survive by keeping out many of the large African predators.

: A

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 B) P → C C) C ↔ P D) P ← C → P E) C ← P →

: A

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. B) a means of reversing the effects of pollution by applying antidote chemicals that have a neutralizing effect on the community. C) an example of how one would use the bottom-up model for community restoration. D) adjusting the numbers of each of the trophic levels back to the numbers that they were before human disturbance. E) monitoring and adjusting the nutrient and energy flow through a community with new technologies.

: A

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 B) 40W, 30X, 20Y, 10Z C) 50W, 25X, 15Y, 10Z D) 70W, 10X, 10Y, 10Z E) 100W, 0X, 0Y, 0Z

: A

38) A community's actual evapotranspiration is a reflection of A) solar radiation, temperature, and water availability. B) the number of plants and how much moisture they lose. C) the depth of the water table. D) wind speed and the frequency of wind gusts. E) plant biomass and plant water content.

: A

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. B) Test fecal samples for H5N1 in Asian waterfowl that live near domestic poultry farms in Asia. C) Test for the presence of H5N1 in poultry used for human consumption worldwide. D) Locate and destroy birds infected with H5N1 in Asian open-air poultry markets. E) Keep domestic and wild fowl from interacting with each other to minimize the probability that wild fowl could get infected and migrate out of Asia.

: A

57) Which island would likely have the lowest extinction rate? A) A B) B C) C D) D E) E

: A

59) Which of the following would be considered a keystone species in McDonaldland? A) Big Mac B) Large French Fries C) Premium Caesar Salad with Crispy Chicken D) Filet-O-Fish E) Chicken McNuggets

: A

66) What interactions exist between a bee and a flower? A) +/+ B) +/o C) +/- D) o/o E) -/-

: A

68) What interactions exist between cellulose-digesting organisms in the gut of a termite and the termite? A) +/+ B) +/o C) +/- D) o/o E) -/-

: A

69) What interactions exist between mycorrhizae and evergreen tree roots? A) +/+ B) +/o C) +/- D) o/o E) -/-

: A

7) 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 chameleon that changes its color to look like a dead leaf D) two species of rattlesnakes that both rattle their tails E) two species of moths with wing spots that look like owl's eyes

: A

9) 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

: A

The symbols +, -, and o are to be used to show the results of interactions between individuals and groups of individuals in the examples that follow. The symbol + denotes a positive interaction, - denotes a negative interaction, and o denotes where individuals are not affected by interacting. The first symbol refers to the first organism mentioned. 63) What interactions exist between a "carrier crab" and "sea urchin hitch-hiker"? A) +/+ B) +/o C) +/- D) o/o E) -/-

: A

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 B) succession C) partitioning D) productivity E) competitive exclusion

: A Topic: Concept 54.3 32) According to the nonequilibrium model, A) communities will remain in a climax state if there are no human disturbances. B) community structure remains stable in the absence of interspecific competition. C) communities are assemblages of closely linked species that are irreparably changed by disturbance. D) interspecific interactions induce changes in community composition over time. E) communities are constantly changing after being influenced by disturbances. Answer: E Topic: Concept 54.3 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 A) equilibrium. B) facilitation. C) immigration. D) inhibition. E) parasitism. Answer: D Topic: Concept 54.3 34) The 1988 Yellowstone National Park lodgepole pine forest fires were likely the result of A) overgrazing by elk. B) infrequent rain episodes. C) years of fire suppression by humans. D) unextinguished campfires. E) geysers. Answer: C Topic: Concept 54.3 35) Why do moderate levels of disturbance result in an increase in community diversity? A) Habitats are opened up for less competitive species. B) Competitively dominant species infrequently exclude less competitive species after a moderate disturbance. C) The environmental conditions become optimal. D) The resulting uniform habitat supports stability, which in turn supports diversity. E) Less-competitive species evolve strategies to compete with dominant species. Answer: A Topic: Concept 54.3 36) Species richness increases A) as we increase in altitude in equatorial mountains. B) as we travel southward from the North Pole. C) on islands as distance from the mainland increases. D) as depth increases in aquatic communities. E) as community size decreases. Answer: B

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) A) pathogen. B) keystone species. C) herbivore. D) resource partitioner. E) mutualistic organism.

: B

27) Which of the following is the most accepted hypothesis as to why invasive species take over communities into which they have been introduced? A) Invasive species are more aggressive than native species in competing for the limited resources of the environment. 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. C) Humans carefully select which species will outcompete nuisance native species. D) Invasive species have a higher reproductive potential than native species. E) Invasive species come from geographically isolated regions, so when they are introduced to regions where there is more competition, they thrive.

: B

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 A) the lethality of each pathogen. B) the mobility of their hosts. C) the fact that viruses are very small. D) innate resistance. E) dormancy viability.

: B

53) Which letter represents an organism that could be a producer? A) A B) B C) C D) D E) E

: B

64) What interactions exist between the cattle egret and grazing cattle? A) +/+ B) +/o C) +/- D) o/o E) -/-

: B

77) The most plausible hypothesis to explain why species richness is higher in tropical than in temperate regions is that A) tropical communities are younger. B) tropical regions generally have more available water and higher levels of solar radiation. C) higher temperatures cause more rapid speciation. D) diversity increases as evapotranspiration decreases. E) tropical regions have very high rates of immigration and very low rates of extinction.

: B

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? A) mutualism B) parasitism C) commensalism D) facilitation E) competition

: B

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? A) competitive exclusion B) resource partitioning C) character displacement D) keystone species E) bottom-up and top-down hypotheses

: B

2) According to the competitive exclusion principle, two species cannot continue to occupy the same A) habitat. B) niche. C) territory. D) range. E) biome.

: B

23) The energetic hypothesis and dynamic stability hypothesis are ideas that attempt to explain A) plant defenses against herbivores. B) the length of food chains. C) the evolution of mutualism. D) resource partitioning. E) competitive exclusion.

: B

3) Which of the following best describes resource partitioning? A) competitive exclusion that results in the success of the superior species B) slight variations in niche that allow similar species to coexist C) two species that can coevolve to share identical niches D) differential resource utilization that results in a decrease in community species diversity E) a climax community that is reached when no new niches are available

: B

37) There are more species in tropical areas than in places more distant from the equator. This is probably a result of A) fewer predators. B) more intense annual solar radiation. C) more frequent ecological disturbances. D) fewer agents of disease. E) fewer predators, more intense annual solar radiation, more frequent ecological disturbances, and fewer agents of disease.

: B

42) Zoonotic disease A) is caused by suborganismal pathogens such as viruses, viroids, and prions only. B) is caused by pathogens that are transferred from other animals to humans by direct contact or by means of a vector. C) can only be spread from animals to humans through direct contact. D) can only be transferred from animals to humans by means of an intermediate host. E) is too specific to study at the community level, and studies of zoonotic pathogens are relegated to organismal biology.

: B

30) In temperate lakes, the surface water is replenished with nutrients during turnovers that occur in the A) autumn and spring. B) autumn and winter. C) spring and summer. D) summer and winter. E) summer and autumn.

A

5) 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.

: B

61) According to the McDonaldland scenario, which of the following would best define an ecological community? A) all of the sandwiches sold at McDonaldland B) the entire menu at McDonaldland C) all of the fast-food restaurants in the United States D) the condiments served at McDonaldland E) the breakfast menu at McDonaldland

: B

74) Keystone predators can maintain species diversity in a community if they A) competitively exclude other predators. B) prey on the community's dominant species. C) allow immigration of other predators. D) reduce the number of disruptions in the community. E) prey only on the least abundant species in the community.

: B

56) Which island would likely exhibit the most impoverished species diversity? A) A B) B C) C D) D E) E

: C

8) 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

: C

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 A) aposmatic coloration. B) cryptic coloration. C) Batesian mimicry. D) Müllerian mimicry. E) mutualism.

: C

17) Which statement best describes the evolutionary significance of mutualism? A) Mutualism offers more biodiversity to a community. B) Individuals partaking in a mutualistic relationship are more resistant to parasites. C) Interaction increases the survival and reproductive rates of mutualistic species. D) Mutualistic interaction lessens competition in communities where it is present. E) Mutualistic relationships allow organisms to synthesize and use energy more efficiently.

: C

21) How did Eugene Odum describe an ecological niche? A) the "address" of an organism B) an entity that is synonymous with an organism's specific trophic level C) an organism's "profession" in the community D) the organism's role in recycling nutrients in its habitat E) the interactions of the organism with other members of the community

: C

30) Why are food chains relatively short? A) Top-level feeders tend to be more numerous than lower-trophic-level species. B) Top-level feeders tend to be small but are capable of conserving more energy. C) Longer chains are less stable and energy transfer between levels is inefficient. D) There are only so many organisms that are adapted to feed on other types of organisms. E) Food chain length is ultimately determined by the photosynthetic efficiency of producers.

: C

41) Which of the following best describes the consequences of white-band disease in Caribbean coral reefs? A) Staghorn coral has been decimated by the pathogen, and Elkhorn coral has taken its place. B) Key habitat for lobsters, snappers, and other reef fishes has improved. C) Algal species take the place of the dead coral, and the fish community is dominated by herbivores. D) Algal species take over and the overall reef diversity increases due to increases in primary productivity. E) Other coral species take the place of the affected Staghorn and Elkhorn species.

: C

46) In terms of community ecology, why are pathogens more virulent now than ever before? A) More new pathogens have recently evolved. B) Host organisms have become more susceptible because of weakened immune systems. C) Human activities are transporting pathogens globally at an unprecedented rate. D) Medicines for treating pathogenic disease are in short supply. E) Sequencing of genes in pathogenic organisms is particularly difficult.

: C

48) During the course of the formation of a parasite/host relationship, a critical first step in this evolution would be A) changing the behavior of the host or intermediate host. B) developing asexual reproduction. C) deriving nourishment without killing the host. D) starting as an ectoparasite and then later becoming an endoparasite. E) utilizing heterotropic nutrition during infection and autotrophic nutrition during dormancy.

: C

54) Which letter represents an organism that could be a primary consumer? A) A B) B C) C D) D E) E

: C

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? A) Study the sales of McDonald's restaurants that are in close proximity to other fast-food restaurants. B) Serve only Big Macs at McDonald's and analyze the sales. C) Remove the Quarter Pounder from the menu and see if Big Mac sales increase. D) Serve Big Macs without the special sauce to see if sales go down. E) Serve Big Macs during breakfast hours.

: C

67) What interactions exist between a tick on a dog and the dog? A) +/+ B) +/o C) +/- D) o/o E) -/-

: C

72) Based on the intermediate disturbance hypothesis, a community's species diversity is increased by A) frequent massive disturbance. B) stable conditions with no disturbance. C) moderate levels of disturbance. D) human intervention to eliminate disturbance. E) intensive disturbance by humans.

: C

75) Food chains are sometimes short because A) only a single species of herbivore feeds on each plant species. B) local extinction of a species causes extinction of the other species in its food chain. C) most of the energy in a trophic level is lost as it passes to the next higher level. D) predator species tend to be less diverse and less abundant than prey species. E) most producers are inedible.

: C

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. 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.

A

Scenario Questions The next series of questions presumes that you have at least once visited and have some knowledge of the fast-food restaurant McDonald's. Use your knowledge of McDonald's and your understanding of community ecology to answer the following questions about an ecological community, McDonaldland. 58) In McDonaldland, which of the following would be an example of an introduced species? A) Big Mac B) Quarter Pounder C) BK Whopper D) Filet-O-Fish E) Double Cheeseburger

: C

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? A) parasitism B) mutualism C) inhibition D) facilitation E) commensalism

: D

39) Why do tropical communities tend to have greater species diversity than temperate or polar communities? A) They are less likely to be affected by human disturbance. B) There are fewer parasites to negatively affect the health of tropical communities. C) Tropical communities are low in altitude, whereas temperate and polar communities are high in altitude. D) Tropical communities are generally older than temperate and polar communities. E) More competitive dominant species have evolved in temperate and polar communities.

: D

43) Of the following zoonotic diseases, which is most likely to be studied by a community ecologist? A) mad cow disease B) hantavirus C) AIDS D) avian flu E) trichinosis

: D

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? A) Their realized niche has expanded. B) They have a competitive relationship with bison. C) They are probably a poor candidate for keystone species. D) Their fundamental niche has been compromised. E) Their fundamental niche has expanded.

: D

19) What percent of all species on Earth are parasites? A) 1% B) 5% C) 25% D) 33 1/3% E) 50%

: D

22) Approximately how many kg of carnivore biomass can be supported by a field plot containing 1,000 kg of plant material? A) 10,000 B) 1,000 C) 100 D) 10 E) 1

: D

40) Which of the following is a correct statement about the McArthur/Wilson Island Equilibrium Model? A) The more species that inhabit an island, the lower the extinction rate. B) As the number of species on an island increases, the emigration rate decreases. C) Competitive exclusion is less likely on an island that has large numbers of species. D) Small islands receive few new immigrant species. E) Islands closer to the mainland have higher extinction rates.

: D

45) Why is a pathogen generally more virulent in a new habitat? A) More pathogens tend to immigrate into newer habitats. B) Intermediate host species are more motile and transport pathogens to new areas. C) Pathogens evolve more efficient forms of reproduction in new environments. D) Hosts in new environments have not had a chance to become resistant to the pathogen through natural selection. E) New environments are almost always smaller in area so that transmission of pathogens is easily accomplished between hosts.

: D

49) Which of the following statements is a valid conclusion of this experiment? A) Balanus can only survive in the lower intertidal zone, because it is unable to resist desiccation. B) Balanus is inferior to Chthamalus in competing for space on intertidal zone rocks. C) The two species of barnacles do not compete with each other because they feed at different times of day. D) When Balanus is removed, it can be observed that the realized niche of Chthamalus is smaller than its fundamental niche. E) These two species of barnacle do not show competitive exclusion. F) If Chthamalus were removed, Balanus's fundamental niche would become larger.

: D

71) The principle of competitive exclusion states that A) two species cannot coexist in the same habitat. B) competition between two species always causes extinction or emigration of one species. C) competition in a population promotes survival of the best-adapted individuals. D) two species that have exactly the same niche cannot coexist in a community. E) two species will stop reproducing until one species leaves the habitat.

: D

76) Which of the following could qualify as a top-down control on a grassland community? A) limitation of plant biomass by rainfall amount B) influence of temperature on competition among plants C) influence of soil nutrients on the abundance of grasses versus wildflowers D) effect of grazing intensity by bison on plant species diversity E) effect of humidity on plant growth rates

: D

Campbell's Biology, 9e (Reece et al.) Chapter 54 Community Ecology The organization of this chapter has remained the same as in previous editions, but questions have been upgraded and revised to reflect the material covered in the 9th edition. More art and scenario question sets have been included for variety. There is an even balance of question skill level from fundamental knowledge to those requiring synthesis and evaluation of material learned. Multiple-Choice Questions 1) Which of the following statements is consistent with the principle of competitive exclusion? A) Bird species generally do not compete for nesting sites. B) The random distribution 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 the less well adapted of two competing species. E) Natural selection tends to increase competition between related species.

: D

12) Which of the following would be most significant in understanding the structure of an ecological community? A) determining how many species are present overall B) determining which particular species are present C) determining the kinds of interactions that occur among organisms of different species D) determining the relative abundance of species 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

: E

71) A population's carrying capacity A) may change as environmental conditions change. B) can be accurately calculated using the logistic growth model. C) generally remains constant over time. D) increases as the per capita growth rate (r) decreases. E) can never be exceeded.

A

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 A) mutualism. B) character displacement. C) Batesian mimicry. D) facultative commensalism. E) resource partitioning.

: E

60) Which two "species" are likely to compete for the same ecological niche? A) Big Mac and Quarter Pounder B) French Fries and Hash Browns C) Premium Caesar Salad with Crispy Chicken and Premium Crispy Chicken Classic Sandwich D) Filet-O-Fish and Double Cheeseburger E) No two species can ever occupy the same ecological niche.

: E

13) Which of the following studies would a community ecologist undertake to learn about competitive interactions? A) selectivity of nest sites among cavity-nesting songbirds B) the grass species preferred by grazing pronghorn antelope and bison C) nitrate and phosphate uptake by various hardwood forest tree species D) stomach analysis of brown trout and brook trout in streams where they coexist 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

: E

18) How might an ecologist test whether a species is occupying its realized or its fundamental niche? A) Study the temperature range and humidity requirements of the species. B) Observe if the niche size changes after the addition of nutritional resources to the habitat. C) Observe if the niche size changes after the introduction of a similar non-native species. D) Measure the change in reproductive success when the species is subjected to environmental stress. E) Remove a competitor species to see if the species expands its range.

: E

50) Connell conducted this experiment to learn more about A) character displacement in the color of barnacles. B) habitat preference in two different species of barnacles. C) desiccation resistance and barnacle species. D) how sea-level changes affect barnacle distribution. E) competitive exclusion and distribution of barnacle species.

: E

51) According to the Shannon Diversity Index, which block would show the greatest diversity? A) 1 B) 2 C) 3 D) 4 E) 5

: E

52) Which letter represents an organism that could be a carnivore? A) A B) B C) C D) D E) E

: E

6) Which of the following is an example of cryptic coloration? A) bands on a coral snake B) brown or gray color of tree bark C) markings of a viceroy butterfly's wings D) colors of an insect-pollinated flower's petals E) a "walking stick" insect that resembles a twig

: E

65) What interactions exist between a lion pride and a hyena pack? A) +/+ B) +/o C) +/- D) o/o E) -/-

: E

70) The feeding relationships among the species in a community determine the community's A) secondary succession. B) ecological niche. C) species richness. D) species-area curve. E) trophic structure.

: E

 60) 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 estimate and people take them for granted. B) They are not worth much and are usually not considered. C) There are no laws that require investigation of ecosystem services in environmental planning. D) There are too many variables to ecosystem services, making their calculation impossible. E) Ecosystem services only take into account abiotic factors that affect local environments.

A

11) Which of the following sets of measurements is the most useful when studying populations? A) density, dispersion, and demographics of a population B) gene frequency over time and the ratio of reproductive to nonreproductive individuals C) annual precipitation averages and mean annual temperatures D) minimum and maximum amounts of precipitation and annual temperature extremes E) ratio of predators and the number of immigrants and emigrants

A

27) In models of logistic population growth, A) the population growth rate slows dramatically as N approaches K. B) new individuals are added to the population most rapidly at the beginning of the population's growth. C) new individuals are added to the population as N approaches K. D) only density-dependent factors affect the rate of population growth. E) carrying capacity is never reached.

A

42) Why do populations grow more slowly as they approach their carrying capacity? A) Density-dependent factors lead to fewer births and increased mortality. B) Density-independent factors lead to fewer births and increased mortality. C) Hormonal changes promote higher death rates in crowded populations. D) Individuals voluntarily stop mating so that overcrowding does not occur. E) The incoming energy decreases in populations experiencing a high rate of increase.

A

46) The use of DDT as an insecticide in the United States has been outlawed since 1971, yet is still a problem for certain top-level carnivores in the United States. Which of the following choices best explains this apparent incongruity? A) DDT is still used for mosquito control in tropical countries, and certain migratory predators can be affected by a seasonal biomagnification. B) DDT is persistent in the environment and all of the pre-1971 DDT is still available in toxic form to poison top-level carnivores. C) Pre-1971 DDT has been deposited in certain habitats, particularly wetlands and estuaries, so predators in these ecosystems are vulnerable to biomagnifications of DDT. D) Whereas most DDT-susceptible species have become resistant to persistent DDT, others are still vulnerable. E) All of the options are correct.

A

52) Which curve best describes survivorship in elephants? A) A B) B C) C D) D E) E

A

53) The biggest challenge that Costa Rica will likely face in its dedication to conservation and restoration in the future is A) the pressures of its growing population. B) its small size (as a country), which may not be able to maintain large enough reserves. C) the potential for disturbance of sensitive species in reserves by ecotourists. D) spread of disease and parasites via corridors from neighboring countries. E) the large number of Costa Rican species already in the extinction vortex.

A

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) B) C) D) E)

A

67) Of the following statements about protected areas that have been established to preserve biodiversity, which one is not correct? A) About 25% of Earth's land area is now protected. B) National parks are one of many types of protected areas. C) Most protected areas are too small to protect species. D) Management of a protected area should be coordinated with management of the land surrounding the area. E) It is especially important to protect biodiversity hot spots.

A

8) According to the U.S. Endangered Species Act (ESA), the difference between an endangered species and a threatened one is that A) an endangered species is closer to extinction. B) a threatened species is closer to extinction. C) threatened species are endangered species outside the U.S. borders. D) endangered species are mainly tropical. E) only endangered species are vertebrates.

A

Art Questions 55) Based on what you know about ecosystem stability and the information provided in the graph, which community (A-E) would likely support the most biodiversity? A) A B) B C) C D) D E) E

A

For the following questions, match the statement with the appropriate term/phrase. 49) This causes an increase in the intensity of UV radiation reaching Earth. A) depletion of ozone layer B) acid precipitation C) biological magnification D) greenhouse effect E) eutrophication

A

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. B) trade winds have a little moisture. C) moisture-laden air is heavier than dry air and is not carried to these latitudes. D) ascending air tends to be moist. E) these locations get the most intense solar radiation of any location on Earth.

A

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. B) Winters and summers in Australia would likely become less distinct seasons. C) Seasonal variation at the equator might decrease. D) Both northern and southern hemispheres would experience summer and winter at the same time. E) Both poles would experience massive ice melts.

A

16) What is the biological significance of genetic diversity between populations? A) Genes for adaptive traits to local conditions make microevolution possible. B) The population that is most fit would survive by competitive exclusion. C) Genetic diversity allows for species stability by preventing speciation. D) Isolated populations become more fit. E) Diseases and parasites are not spread between separated populations.

A

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. B) have thin seed coats. C) produce well-provisioned seeds. D) have seeds that become viable only after a forest fire. E) disperse many seeds in close proximity to the parent tree.

A

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. B) air masses that are dried and heated over continental areas that rise, cool aloft, and descend over oceanic areas followed by a return flow of moist air from ocean to land, delivering high amounts of precipitation to coastal areas. C) polar, cool, moist high-pressure air masses from the poles that move along the surface, releasing precipitation along the way to the equator where they are heated and dried. D) the revolution of Earth around the sun. E) mountain ranges that deflect air masses containing variable amounts of moisture.

A

21) Of the following ecosystem types, which have been impacted the most by humans? A) wetland and riparian B) open and benthic ocean C) desert and high alpine D) taiga and second-growth forests E) tundra and arctic

A

21) Which of the following is the equation for zero population growth (ZPG)? A) R = b - m B) dN/dt = rN C) dN/dt =rmax N (K -N)/K D) dN/dt =rmax N E) dN/dt = 1.0N

A

23) Which of the following can be said about light in aquatic environments? A) Water selectively reflects and absorbs certain wavelengths of light. B) Photosynthetic organisms that live in deep water probably use red light. C) Longer wavelengths penetrate to greater depths. D) Light penetration seldom limits the distribution of photosynthetic species. E) Most photosynthetic organisms avoid the surface where the light is too intense.

A

24) Which of the following is a type of research in which a conservation biologist would be involved? A) reestablishing whooping cranes in their former breeding grounds in North Dakota B) studying species diversity and interaction in the Florida Everglades, past and present C) studying population ecology of grizzly bears in Yellowstone National Park D) determining the effects of hunting white-tailed deer in Vermont E) determining the effect of protection programs on the recovery of the North Atlantic cod fishery

A

28) The Allee effect is used to describe a population that A) has become so small that it will have difficulty surviving and reproducing. B) has become so large that it will have difficulty surviving and reproducing. C) is viable and stable at its carrying capacity. D) has exceeded its carrying capacity. E) is in crash decline.

A

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 B) dispersion C) carrying capacity D) cohorts E) range

A

33) The primary difference between the small-population approach (S-PA) and the declining-population approach (D-PA) to biodiversity recovery is A) S-PA is interested in bolstering the genetic diversity of a threatened population rather than the environmental factors that caused the population's decline. B) S-PA kicks in for conservation biologists when population numbers fall below 500. C) D-PA would likely involve bringing together individuals from scattered small populations to interbreed in order to promote genetic diversity. D) S-PA would investigate and eliminate all of the human impacts on the habitat of the species being studied for recovery. E) D-PA would use recently collected population data to calculate an extinction vortex.

A

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. B) a eutrophic lake. C) a relatively shallow lake. D) a nutrient-rich lake. E) a lake with consistently warm temperatures.

A

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 B) coral reef C) intertidal D) pelagic E) estuary

A

36) Which of the following is characteristic of K-selected populations? A) offspring with good chances of survival B) many offspring per reproductive episode C) small offspring D) a high intrinsic rate of increase E) early parental reproduction

A

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 B) the ratio of females to males, the length of the breeding season, and the number of offspring for each reproductive episode C) the number of offspring produced over a lifetime by a breeding pair and the survivability of the offspring D) timing breeding sessions with optimal environmental conditions and the number of offspring produced during each breeding session E) the amount of parental care given after birth, the number of reproductive episodes per year, and the number of years females are capable of producing viable offspring

A

41) 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

A

44) Which of the following is true about "hot spots"? A) One-third of all species on Earth occupy less than 1.5% of Earth's land area (hot spots). B) All of the plants and animals containing genes that may be useful to humankind are located in Earth's hot spots. C) Around 75% of all of the undiscovered species of organisms live in ecological hot spots. D) As conservation measures improve over the next ten years, hot spots will likely disappear. E) The hot spots that are in most dire need of remediation are located in the tundra.

A

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. B) for a person living in a developing country to see how much of the world's resources are left for him/her. C) in converting human foods' meat biomass to plant biomass. D) in making predictions about the global carrying capacity of humans. E) in determining which nations produce the least amount of carbon dioxide from the burning of fossil fuels.

A

5) Which of the following choices includes all of the others in creating global terrestrial climates? A) differential heating of Earth's surface B) ocean currents C) global wind patterns D) evaporation of water from ocean surfaces E) Earth's rotation on its axis

A

54) Which curve best describes survivorship in humans who live in undeveloped nations? A) A B) B C) C D) D E) E

A

54) Which of the following nations has become a world leader in the establishment of zoned reserves? A) Costa Rica B) Canada C) China D) United States E) Mexico

A

6) Which of the following groups would be most likely to exhibit uniform dispersion? A) red squirrels, who actively defend territories B) cattails, which grow primarily at edges of lakes and streams C) dwarf mistletoes, which parasitize particular species of forest tree D) moths, in a city at night E) lake trout, which seek out cold, deep water high in dissolved oxygen

A

60) Which zone experiences the most abiotic change over a 24-hour period? A) A B) B C) C D) D E) E

A

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 B) II C) III D) No differences in the magnitude of future unemployment would be expected among these populations. E) It is not possible to infer anything about future social conditions from age-structure diagrams.

A

65) Which of the following is a consequence of biological magnification? A) Toxic chemicals in the environment pose greater risk to top-level predators than to primary consumers. B) Populations of top-level predators are generally smaller than populations of primary consumers. C) The biomass of producers in an ecosystem is generally higher than the biomass of primary consumers. D) Only a small portion of the energy captured by producers is transferred to consumers. E) The amount of biomass in the producer level of an ecosystem decreases if the producer turnover time increases.

A

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 B) exponential growth curves and unlimited environmental resources C) density-independent population regulation and chance occurrence D) pollution effects of a natural environment and learned shrimp behavior E) a K-selected population switching to an r-selected population

A

71) When climbing a mountain, we can observe transitions in biological communities that are analogous to the changes A) in biomes at different latitudes. B) at different depths in the ocean. C) in a community through different seasons. D) in an ecosystem as it evolves over time. E) across the United States from east to west.

A

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 B) savanna C) desert D) temperate broadleaf forest E) temperate grassland

A

79) Which of the following statements about human population in industrialized countries is incorrect? A) Life history is r-selected. B) Average family size is relatively small. C) The population has undergone the demographic transition. D) The survivorship curve is Type I. E) Age distribution is relatively uniform.

A

The eight climographs below show yearly temperature (line graph and left vertical axis) and precipitation (bar graph and right vertical axis) averages for each month for some locations on Earth. Choose the climograph that best answers the question or completes the statement. Climographs may be used once, more than once, or not at all. 50) Which climograph shows the climate for location 1? A) A B) C C) E D) G E) H

A

34) Which of the following pairs of reproductive strategies is consistent with energetic trade-off and reproductive success? A) Pioneer species of plants produce many very small, highly airborne seeds, whereas large elephants that are very good parents produce many offspring. 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. C) Species that have to broadcast to distant habitats tend to produce seeds with heavy protective seed coats, and animals that are caring parents produce fewer offspring with lower infant mortality. D) Free-living insects lay thousands of eggs and provide no parental care, whereas flowers take good care of their seeds until they are ready to germinate. E) Some mammals will not reproduce when environmental resources are low so they can survive until conditions get better, and plants that produce many small seeds are likely found in stable environments.

B

78) During exponential growth, a population always A) grows by thousands of individuals. B) grows at its maximum per capita rate. C) quickly reaches its carrying capacity. D) cycles through time. E) loses some individuals to emigration.

B

End-of-Chapter Questions The following questions are from the end-of-chapter "Test Your Understanding" section in Chapter 53 of the textbook. 70) Population ecologists follow the fate of same-age cohorts to A) determine a population's carrying capacity. B) determine the birth rate and death rate of each group in a population. C) determine if a population is regulated by density-dependent processes. D) determine the factors that regulate the size of a population. E) determine if a population's growth is cyclic.

B

1) Population ecologists are primarily interested in A) studying interactions among populations of organisms that inhabit the same area. B) understanding how biotic and abiotic factors influence the density, distribution, size, and age structure of populations. C) how humans affect the size of wild populations of organisms. D) how populations evolve as natural selection acts on heritable variations among individuals and changes in gene frequency. E) the overall vitality of a population of organisms.

B

12) Which of the following scenarios would provide the most legitimate data on population density? A) Count the number of nests of a particular species of songbird and multiply this by a factor that extrapolates these data to actual animals. 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. C) Use the mark-and-recapture method to estimate the size of the population. D) Calculate the difference between all of the immigrants and emigrants to see if the population is growing or shrinking. E) Add the number of births and subtract the individuals that die to see if the population's density is increasing or decreasing.

B

13) The most serious consequence of a decrease in global biodiversity would be the A) increase in global warming and thinning of the ozone layer. B) potential loss of ecosystem services on which people depend. C) increase in the abundance and diversity of edge-adapted species. D) loss of source of genetic diversity to preserve endangered species. E) loss of species for "bioprospecting."

B

15) The main reason polar regions are cooler than the equator is that A) there is more ice at the poles. B) sunlight strikes the poles at a lower angle. C) the poles are farther from the sun. D) the polar atmosphere is thinner and contains fewer greenhouse gases. E) the poles are permanently tilted away from the sun.

B

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. A) 120 individuals added B) 40 individuals added C) 20 individuals added D) 400 individuals added E) 20 individuals lost

B

18) Overexploitation encourages extinction and is most likely to affect A) animals that occupy a broad ecological niche. B) large animals with low intrinsic reproductive rates. C) most organisms that live in the oceans. D) terrestrial organisms more than aquatic organisms. E) edge-adapted species.

B

2) Which of the following levels of ecological 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

B

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? A) The cool, moist Pacific air heats up as it rises, releasing its precipitation as it passes the tops of the mountains, and this warm, now dry air cools as it descends on the leeward side of the range. 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. C) The cool, dry Pacific air heats up and picks up moisture from evaporation of the snowcapped peaks of the mountain range, releasing this moisture as precipitation when the air cools while descending on the leeward side of the range. D) These air masses are blocked by the mountain ranges, producing high annual amounts of precipitation on the windward sides of these mountain ranges. E) These air masses remain essentially unchanged in moisture content and temperature as they pass over these mountain ranges.

B

21) If global warming continues at its present rate, which biomes will likely take the place of the coniferous forest (taiga)? A) tundra and polar ice B) temperate broadleaf forest and grassland C) desert and chaparral D) tropical forest and savanna E) chaparral and temperate broadleaf forest

B

22) The introduction of the brown tree snake in the 1940s to the island of Guam has resulted in A) eradication of non-native rats and other undesirable/pest species. B) the extirpation of many of the island's bird and reptile species. C) a good lesson in biological control. D) a new species of hybrids from crossbreeding with a native snake species. E) its failure to compete with native species and its quick elimination from the island.

B

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? A) Remove, to the mineral soil, all of the organisms from an experimental plot and monitor the colonization of the area over time in terms of both species diversity and abundance. 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. C) Compare and contrast the flora and fauna of warm/cold/dry/wet climates to shed light on how they evolved to be suited to their present-day environment. D) Quantify the impact of man's activities on present-day populations of threatened and endangered species to assess the rate of extirpation and extinction. E) There is no scientific investigation that can help make predictions on the future distribution of organisms.

B

26) 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.

B

31) The word triage originated during World War I and was first used by French doctors in prioritizing patients based on the severity of their wounds, because there were more wounded soldiers in need of urgent care than there were resources to treat them. Conservation biologists have to make similar determinations with degraded ecosystems. Which of the following is the most important consideration when it comes to managing for maintenance of biodiversity? A) identifying large, high-profile vertebrates first, because steps to saving them would be most recognized by the public B) determining which species is most important for conserving biodiversity as a whole C) replanting suitable habitat for fauna D) assessing the economic costs and the gains for society E) maintaining optimum size of all populations in the ecosystem

B

32) Which of the following species was driven to extinction by overexploitation by hunters/fishermen? A) African elephant B) the great auk C) North American bluefin tuna D) flying foxes E) American bison

B

33) Which marine zone would have the lowest rates of primary productivity (photosynthesis)? A) pelagic B) abyssal C) neritic D) continental shelf E) intertidal

B

35) Managing southwestern forests specifically for the red-cockaded woodpecker A) was wholeheartedly supported by the timber extraction industry. B) contributed to greater abundance and diversity of other forest bird species. C) caused other species of songbird to decline. D) involved strict fire suppression measures. E) involved the creation of fragmented forest habitat.

B

36) Which of the following is true about the current research regarding forest fragmentation? A) Fragmented forests support a greater biodiversity because they result in the combination of forest-edge species and forest-interior species. B) Fragmented forests support a lesser biodiversity because the forested-adapted species leave, and only the edge and open-field species can occupy fragmented forests. C) Fragmented forests are the goal of conservation biologists who design wildlife preserves. D) Harvesting timber that results in forest fragmentation results in less soil erosion. E) The disturbance of timber extraction causes the species diversity to increase because of the new habitats created.

B

37) Which of the examples below provides appropriate abiotic and biotic factors that might determine the distribution of the species in question? A) the amount of nitrate and phosphate in the soil, and wildflower abundance and diversity B) the number of frost-free days, and competition between species of introduced grasses and native alpine grasses C) increased predation and decreased food availability, and a prairie dog population after a prairie fire D) available sunlight and increased salinity in the top few meters of the ocean, and the abundance and diversity of phytoplankton communities E) the pH and dissolved oxygen concentration, and the streams in which brook trout can live

B

38) Which pattern of reproduction is correctly paired with a species? A) iteroparityPacific salmon B) iteroparityelephant C) semelparityoak tree D) semelparityrabbit E) semelparity-polar bear

B

39) Cowbirds utilize fragmented forests effectively by A) feeding on the fruits of shrubs that tend to grow at the forest/open-field interface. B) parasitizing the nests of forest birds, and feeding on open-field insects. C) roosting in forest trees, and nesting in grassy fields. D) outcompeting other songbird species in fragmented communities. E) using forest cover to escape from predators in their normal grassland habitat.

B

41) Which of the following is most likely to contribute to density-dependent regulation of populations? A) the removal of toxic waste by decomposers B) intraspecific competition for nutrients C) earthquakes D) floods E) fires

B

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 A) parallel evolution. B) convergent evolution. C) allopatric speciation. D) introgression. E) gene flow.

B

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? A) Owl populations frequent the area more often because of increased hunting success. B) Females undergo hormonal changes that delay sexual maturation and many individuals suffer depressed immune systems and die due to the stress of overpopulation. C) Clumped dispersion of the population leads to increased spread of disease and parasites, resulting in a population crash. D) All of the resources (food and shelter) are used up by overpopulation and much of the population dies of exposure and/or starvation. E) Because the individuals are vulnerable they are more likely to die off if a drought or flood were to occur.

B

43) In which of the following terrestrial biome pairs are both parts dependent upon periodic burning? A) tundra and coniferous forest B) chaparral and savanna C) desert and savanna D) tropical forest and temperate broadleaf forest E) grassland and tundra

B

43) What is the biggest problem with selecting a site for a preserve? A) There is always a conflict about use of land set aside for preservation. B) Making a proper selection is difficult because currently the environmental conditions of almost any site change so quickly. C) Keystone species are difficult to identify in potential preserve sites. D) Only lands that are not useful to human activities are available for preserves. E) Most of the best sites are inaccessible by land transportation, so making roads to them is often prohibitively expensive.

B

44) Fire suppression by humans A) will always result in an increase in species diversity in a given biome. B) can change the species composition within biological communities. C) will result ultimately in sustainable production of increased amounts of forest products for human use. D) is necessary for the protection of threatened and endangered forest species. E) is a management goal of conservation biologists to maintain the healthy condition of forest communities.

B

45) Which of the following statements best describes the interaction between fire and ecosystems? A) The likelihood of a wildfire occurring 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 suppression of forest fires by man has prevented certain communities, such as grasslands, from reaching their climax stage. D) Chaparral communities have evolved to the extent that they rarely burn. E) Fire is unnatural in ecosystems and should be prevented.

B

47) Agricultural lands frequently require nutrient augmentation because A) nitrogen-fixing bacteria are not as plentiful in agricultural soils because of the use of pesticides. B) the nutrients that become the biomass of plants are not cycled back to the soil on lands where they are harvested. C) land that is available for agriculture tends to be nutrient-poor. D) grains raised for feeding livestock must be fortified, and thus require additional nutrients. E) cultivation of agricultural land inhibits the decomposition of organic matter.

B

54) Which climograph shows the climate for location 5? A) A B) C C) D D) E E) H

B

57) Which zone produces the most global oxygen gas? A) A B) B C) C D) D E) E

B

65) Which lake zone would be absent in a very shallow lake? A) benthic zone B) aphotic zone C) pelagic zone D) littoral zone E) limnetic zone

B

7) Which of the following terms includes all of the others? A) species diversity B) biodiversity C) genetic diversity D) ecosystem diversity E) species richness

B

9) Which statement describes how climate might change if Earth was 75% land and 25% water? A) Terrestrial ecosystems would likely experience more precipitation. B) Earth's daytime temperatures would be higher and nighttime temperatures lower. C) Summers would be longer and winters shorter at midlatitude locations. D) Earth would experience an unprecedented global warming. E) More terrestrial microclimates would be created because of daily fluctuations in climate.

B

The following questions refer to Figure 53.3, which depicts the age structure of three populations. Figure 53.3 61) Which population(s) is (are) in the process of decreasing? A) I B) II C) III D) I and II E) II and III

B

rainfall is consistently high in Labrador. D) Labrador is too windy to support tall plants, such as palm trees. E) Labrador receives sunlight of lower duration and intensity than does Land's End.

B

29) Carrying capacity is A) seldom reached by marine producers and consumers because of the vast resources of the ocean. B) the maximum population size that a particular environment can support. C) fixed for most species over most of their range most of the time. D) determined by density and dispersion data. E) the term used to describe the stress a population undergoes due to limited resources.

B Topic: Concept 53. 3 30) Which of the following causes populations to shift most quickly from an exponential to a logistic population growth? A) increased birth rate B) removal of predators C) decreased death rate D) competition for resources E) favorable climatic conditions Answer: D

 56) Study the information above about quail habitats. Which of these represents the best quail habitat in terms of fragmentation and edge? A) A B) B C) C D) D E) E

C

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? A) 6,000 B) 42,275 C) 60,000 D) 140,000 E) 600,000

C

26) 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

C

30) Modern conservation biology 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 genetic diversity in all species. E) saving as much habitat as possible from development and exploitation.

C

31) 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.

C

38) How is habitat fragmentation related to biodiversity loss? A) Less carbon dioxide is absorbed by plants in fragmented habitats. B) In fragmented habitats, more soil erosion takes place. C) Populations of organisms in fragments are smaller and, thus, more susceptible to extinction. D) Animals are forced out of smaller habitat fragments. E) Fragments generate silt that negatively affects sensitive river and stream organisms.

C

4) 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 experiencing an extinction (loss of 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 high and human activities threaten biodiversity at all levels. 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.

C

42) Biodiversity hot spots are not necessarily the best choice for nature preserves because A) hot spots are situated in remote areas not accessible to wildlife viewers. B) their ecological importance makes land purchase very expensive. C) a hot spot for one group of organisms may not be a hot spot for another group. D) hot spots are designated by abiotic factors present, not biotic factors. E) designated hot spots change on a daily basis.

C

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? A) B) C) D) E)

C

Refer to Figure 53.4 and then answer the following questions. 65) What is a logical conclusion that can be drawn from the graphs above? A) Developed countries have lower infant mortality rates and lower life expectancy than developing countries. B) Developed countries have higher infant mortality rates and lower life expectancy than developing countries. C) Developed countries have lower infant mortality rates and higher life expectancy than developing countries. D) Developed countries have higher infant mortality rates and higher life expectancy than developing countries. E) Developed countries have a life expectancy that is about 42 years more than life expectancy in developing countries.

C

1) Which of the following ecological locations has the greatest species diversity? A) tundra B) deciduous forests C) tropics D) grasslands E) islands

C

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? A) These immigrants make up for the deaths of individuals, keeping the other populations' size stable. B) Young reproductive males tend to stay in their home population and are not driven out by other territorial males. C) These immigrants provide a source of genetic diversity for the other populations. D) Those individuals that emigrate to these new populations are looking for less crowded conditions with more resources. E) Gradually, the populations of ground squirrels will move from a clumped to a uniform population pattern of dispersion.

C

10) 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

C

11) What term did E. O. Wilson coin for our innate appreciation of wild environments and living organisms? A) bioremediation B) bioethics C) biophilia D) biophobia E) landscape ecology

C

13) Which of the following is the best example of uniform distribution? A) bees collecting pollen in a wildflower meadow B) snails in an intertidal zone at low tide C) territorial songbirds in a mature forest during mating season D) mushrooms growing on the floor of an old growth forest E) a cultivated cornfield in the Midwest

C

16) Why do some invertebrates, such as lobsters, show a "stair-step" survivorship curve? A) Many invertebrates mate and produce offspring on multiyear cycles. B) Within a species of invertebrates, younger individuals have a higher survivorship than older individuals. C) Many invertebrates molt in order to grow, and they are vulnerable to predation during their "soft shell" stage. D) Many invertebrate species have population cycles that go up and down according to the frequency of sunspots. E) The number of fertilized eggs that mature to become females in many species of invertebrates is based on ambient temperature.

C

17) 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.

C

2) A population is correctly defined as having which of the following characteristics? I. inhabiting the same general area II. belonging to the same species III. possessing a constant and uniform density and dispersion A) I only B) III only C) I and II only D) II and III only E) I, II, and III

C

22) Which of the following are important biotic factors that can affect the structure and organization of biological communities? A) precipitation, wind B) nutrient availability, soil pH C) predation, competition D) temperature, water E) light intensity, seasonality

C

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? A) Old growth, because of stable conditions that would favor exponential growth of all species in the forest. B) Old growth, because each of the species is well established and can produce many offspring. C) Logged, because the disturbed forest affords more resources for increased specific populations to grow. D) Logged, because the various populations are stimulated to a higher reproductive potential. E) Exponential growth is equally probable in old-growth and logged forests.

C

27) 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

C

3) Estimates of current rates of extinction A) indicate that we have reached a state of stable equilibrium in which speciation rates equal extinction rates. B) suggest that one-half of all animal and plant species may be gone by the year 2100. C) indicate that rates may be greater than the mass extinctions at the close of the Cretaceous period. D) indicate that only 1% of all of the species that have ever lived on Earth are still alive. E) suggest that rates of extinction have decreased globally.

C

3) Which of the following examples of an ecological effect leading to an evolutionary effect is most correct? A) When seeds are not plentiful, trees produce more seeds. B) A few organisms of a larger population survive a drought and then these survivors emigrate to less arid environments. 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. D) Fish that swim the fastest in running water catch the most prey and more easily escape predation. E) The insects that spend the most time exposed to sunlight have the most mutations.

C

33) The three basic variables that make up the life history of an organism are A) life expectancy, birth rate, and death rate. B) number of reproductive females in the population, age structure of the population, and life expectancy. C) age when reproduction begins, how often reproduction occurs, and how many offspring are produced per reproductive episode. D) how often reproduction occurs, life expectancy of females in the population, and number of offspring per reproductive episode. E) the number of reproductive females in the population, how often reproduction occurs, and death rate.

C

37) Relatively small geographic areas with high concentrations of endemic species and a large number of endangered and threatened species are known as A) endemic sinks. B) critical communities. C) biodiversity hot spots. D) endemic metapopulations. E) bottlenecks.

C

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 A) conclude that lower elevations are limiting to the survival of this species. B) study the anatomy and physiology of this species. C) investigate the various biotic and abiotic factors that are unique to high altitude. D) analyze the soils found in the vicinity of these trees, looking for unique chemicals that may support their growth. E) collect data on temperature, wind, and precipitation at several of these locations for a year.

C

40) In which of the following situations would you expect to find the largest number of K-selected individuals? A) a recently abandoned agricultural field in Ohio B) the sand dune communities of south Lake Michigan C) the flora and fauna of a coral reef in the Caribbean D) South Florida after a hurricane E) a newly emergent volcanic island

C

40) Which of the following is consistent with forest fragmentation research? A) Productivity is the same in both fragmented forests and forest interiors. B) Edge communities consistently have low species diversity. C) Forest-interior species show declines in small patch communities. D) New-edge species that migrate in do not seem to compete with forest species and often increase biodiversity in fragmented forests. E) Species diversity is always lower in fragmented forests when compared to forest interiors in the same region.

C

40) Which of the following statements best describes the effect of climate on biome distribution? A) Average annual temperature and precipitation are sufficient to predict which biome will be found in an area. B) Seasonal fluctuation of temperature is not a limiting factor in biome distribution if areas have the same annual temperature and precipitation means. C) Not only is the average climate important in determining biome distribution but so is the pattern of climatic variation. D) Temperate forests and grasslands are different biomes because they receive a different quality and quantity of sunlight, even though they have essentially the same annual temperature and precipitation. E) Correlation of climate with biome distribution is sufficient to determine the cause of biome patterns.

C

41) How are movement corridors potentially harmful to certain species? A) They increase inbreeding. B) They promote dispersion. C) They spread disease and parasites. D) They increase genetic diversity. E) They allow seasonal migration.

C

44) Why is territoriality an adaptive behavior for songbirds maintaining populations at or near their carrying capacity? A) Songbirds expend a tremendous amount of energy defending territories so that they spend less time feeding their young and fledgling mortality increases. B) Only the fittest males defend territories and they attract the fittest females so the best genes are conveyed to the next generation. C) Songbird males defend territories commensurate with the size from which they can derive adequate resources for themselves, their mate, and their chicks. D) Many individuals are killed in the agonistic behaviors that go along with territorial defense. E) Adult songbirds make improvements to the territories they inhabit so that they can produce successfully fledged chicks.

C

48) Which of the following is most key to understanding the demographic transition in human population growth? A) education of global famine B) improved worldwide health care C) voluntary reduction of family size D) improved sanitary conditions in the world's hospitals E) reduction of casualties of war

C

50) Which statement is true with regard to human population growth? A) It is at a zero reproduction rate. B) Its rate of increase continues to grow at an exponential rate. C) Its rate of growth is slowing. D) Its rate of growth is increasing. E) There is no scientific prediction that can be made about human population growth.

C

52) This causes extremely high levels of toxic chemicals in fish-eating birds. A) depletion of ozone layer B) acid precipitation C) biological magnification D) greenhouse effect E) eutrophication

C

52) Which climograph shows the climate for location 3? A) B B) C C) D D) E E) F

C

55) Which of the following best substantiates why location 3 is an equatorial (tropical) climate? A) It has a monsoon season during the winter months. B) It has consistent monthly averages for rainfall. C) The temperature is high for each monthly average. D) The temperatures reach 100°F during some months. E) The temperatures are lower in June, July, and August.

C

58) Which zone is comprised largely of detritus-feeding organisms? A) A B) B C) C D) D E) E

C

59) Why were ecologists concerned about the shift in the peak caterpillar season from June 3, 1980, to May 15, 2000? A) The caterpillars would have eaten much of the foliage of the trees where flycatchers would have nested, rendering their nests more open to predation. B) The earlier hatching of caterpillars would compete with other insect larval forms which the flycatchers would also use to feed their young. C) The 2000 flycatcher nestlings would miss the peak caterpillar season and might not be as well fed. D) The flycatchers would have to migrate sooner to match their brood-rearing to the time of peak caterpillar season. E) Pesticides, which have a negative effect on the ecosystem, would have to be used to control the earlier outbreak of caterpillar hatching.

C

6) Although extinction is a natural process, current extinctions are of concern to environmentalists because A) more animals than ever before are going extinct. B) most current extinctions are caused by introduced species. C) the rate of extinction is unusually high. D) current extinction is primarily affecting plant diversity. E) None of the options are correct.

C

6) Why is the climate drier on the leeward side of mountain ranges that are subjected to prevailing winds? A) Deserts usually are found on the leeward side of mountain ranges. B) The sun illuminates the leeward side of mountain ranges at a more direct angle, converting to heat energy, which evaporates most of the water present. 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. D) Air masses pushed by the prevailing winds are stopped by mountain ranges and the moisture is used up in the stagnant air masses on the leeward side. E) More organisms live on the sheltered, leeward side of mountain ranges where their utilization of water lowers the amount available when compared to the windward side.

C

62) Which population(s) appear(s) to be stable? A) I B) II C) III D) I and II E) II and III

C

64) Assuming these age-structure diagrams describe human populations, which population(s) is (are) likely to experience zero population growth (ZPG)? A) I B) II C) III D) I and II E) II and III

C

66) Which of the following strategies would most rapidly increase the genetic diversity of a population in an extinction vortex? A) Capture all remaining individuals in the population for captive breeding followed by reintroduction to the wild. B) Establish a reserve that protects the population's habitat. C) Introduce new individuals transported from other populations of the same species. D) Sterilize the least fit individuals in the population. E) Control populations of the endangered population's predators and competitors.

C

7) To construct a reproductive table for a sexual species, one needs to A) assess sperm viability for the males in the population. 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) analyze the ratio of deaths to births in a cohort.

C

70) Which statement about dispersal is false? A) Dispersal is a common component of the life cycles of plants and animals. B) Colonization of devastated areas after floods or volcanic eruptions depends on dispersal. C) Dispersal occurs only on an evolutionary time scale. D) Seeds are important dispersal stages in the life cycles of most flowering plants. E) The ability to disperse can expand the geographic distribution of a species.

C

72) Scientific study of the population cycles of the snowshoe hare and its predator, the lynx, has revealed that A) the prey population is controlled by predators alone. B) hares and lynx are so mutually dependent that each species cannot survive without the other. C) multiple biotic and abiotic factors contribute to the cycling of the hare and lynx populations. D) both hare and lynx populations are regulated mainly by abiotic factors. E) the hare population is r-selected and the lynx population is K-selected.

C

73) If the direction of Earth's rotation reversed, the most predictable effect would be A) no more night and day. B) a big change in the length of the year. C) winds blowing from west to east along the equator. D) a loss of seasonal variation at high latitudes. E) the elimination of ocean currents.

C

75) The observation that members of a population are uniformly distributed suggests that A) the size of the area occupied by the population is increasing. B) resources are distributed unevenly. C) the members of the population are competing for access to a resource. D) the members of the population are neither attracted to nor repelled by one another. E) the density of the population is low.

C

76) According to the logistic growth equation = rmaxN A) the number of individuals added per unit time is greatest when N is close to zero. B) the per capita growth rate (r) increases as N approaches K. C) population growth is zero when N equals K. D) the population grows exponentially when K is small. E) the birth rate (b) approaches zero as N approaches K.

C

Experts in white-tailed deer ecology generally agree that population sizes of deer that live in temperate climates are limited by winter snow. The deer congregate in "yarding" areas under evergreen trees because venturing out to feed in winter is energetically too expensive when snowfall depths accumulate to above 40 cm. Deer often stay yarded until the spring thaw. Snow depth over 40 inches for more than 60 days results in high mortality due to starvation. 62) This observation best illustrates which of the following principles about factors that limit distribution of organisms? A) Abiotic factors, such as weather extremes, ultimately limit distribution. B) Organisms will face extinction unless they adapt to conditions or evolve new mechanisms for survival. C) Environmental factors are limiting not only in amount but also in longevity. D) Daily accumulations in snow depth gradually add up to cause increased deer mortality. E) Temporary extremes in weather conditions usually result in high mortality in the deer population.

C

The diagram shows a generalized cross section of the marine environment with various zones labeled with letters. Choose the letter that best answers the question. Letters may be used once, more than once, or not at all. 56) Which zone has a condition of constant temperature? A) A B) B C) C D) D E) E

C

The following questions are from the end-of-chapter "Test Your Understanding" section in Chapter 52 of the textbook. 64) Which of the following areas of study focuses on the exchange of energy, organisms, and materials between ecosystems? A) population ecology B) organismal ecology C) landscape ecology D) ecosystem ecology E) community ecology

C

Use this description to answer the following question. In areas of permafrost, stands of black spruce are frequently observed in the landscape, while other tree species are noticeably absent. Often these stands are referred to as "drunken forests" because many of the black spruce are displaced from their normal vertical alignment. 63) What might be the adaptive significance of these unusual forests growing the way they do in this marginal habitat? A) Needles are adapted to withstand cold arctic temperatures. B) Branches are adapted to absorb more CO2 with this displaced alignment. C) Taproot formation is impossible, so trees developed shallow root beds. D) Trees are tilted so snow prevents them from breaking or tipping over. E) Trees tip so that they do not compete with each other for sunlight.

C

 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? A) 160 B) 200 C) 400 D) 1,600 E) 80,000

D

 Flycatcher birds that migrate from Africa to Europe feed their nestlings a diet that is almost exclusively moth caterpillars. The graph below shows the mean dates of arrival, bird hatching, and peak caterpillar season for the years 1980 and 2000. 58) The shift in the peak of caterpillar season is most likely due to A) pesticide use. B) earlier migration returns of flycatchers. C) an innate change in the biological clock of the caterpillars. D) global warming. E) acid precipitation in Europe.

D

15) Which of the following best defines a cohort? A) a group of individuals that inhabits a small isolated region within the range for the species B) all of the individuals that are annually added to a population by birth and immigration C) the reproductive males and females within the population D) a group of the individuals from the same age group, from birth until they are all dead E) the number of individuals that annually die or emigrate out of a population

D

34) The long-term problem with red-cockaded woodpecker habitat intervention in the southwest United States is A) the only habitat that can support their recovery is large tracts of mature southern pine forest. B) the mature pine forests in which they live cannot ever be subjected to forest fire. C) all of the appropriate red-cockaded woodpecker habitat has already been logged or converted to agricultural land. D) the social organization of the red-cockaded woodpecker precludes the dispersal of reproductive individuals. E) what habitat remains for the red-cockaded woodpecker does not contain trees suitable for nest-cavity construction.

D

63) The main cause of the increase in the amount of CO2 in Earth's atmosphere over the past 150 years is A) increased worldwide primary production. B) increased worldwide standing crop. C) an increase in the amount of infrared radiation absorbed by the atmosphere. D) the burning of larger amounts of wood and fossil fuels. E) additional respiration by the rapidly growing human population.

D

Please read the paragraph below and review Figure 53.2 to answer the following question. Researchers in the Netherlands studied the effects of parental care given in European kestrels over five years. The researchers transferred chicks among nests to produce reduced broods (three or four chicks), normal broods (five or six chicks), and enlarged broods (seven or eight chicks). They then measured the percentage of male and female parent birds that survived the following winter. (Both males and females provide care for chicks.) Figure 53.2: Brood size manipulations in the kestrel: Effects on offspring and parent survival. 58) Which of the following is a conclusion that can be drawn from this graph? A) Female survivability is more negatively affected by larger brood size than is male survivability. B) Male survivability decreased by 50% between reduced and enlarged brood treatments. C) Both males and females had increases in daily hunting with the enlarged brood size. D) There appears to be a negative correlation between brood enlargements and parental survival. E) Chicks in reduced brood treatment received more food, weight gain, and reduced mortality.

D

10) To better comprehend the magnitude of current extinctions, it will be necessary to A) monitor atmospheric carbon dioxide levels more closely. B) differentiate between plant extinction and animal extinction numbers. 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.

D

14) Which of the following is the most direct threat to biodiversity? A) increased levels of atmospheric carbon dioxide B) the depletion of the ozone layer C) overexploitation of selected species D) habitat destruction E) zoned reserves

D

15) 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) overexploitation of certain species. D) alteration or destruction of the physical habitat. E) global climate change resulting from a variety of human activities.

D

19) How might the extinction of some Pacific Island bats called "flying foxes" threaten the survival of over 75% of the tree species in those islands? A) The bats eat the insects that harm competitor plants. B) The bats consume the fruit including the seeds that would disrupt the trees' reproductive cycle. C) The bats roost in the trees and fertilize soil around the trees with their nitrogen-rich droppings. D) The bats pollinate the trees and disperse seeds. E) The bats pierce the fruit, which allows the seeds to germinate.

D

2) What is the estimated number of extant species on Earth? A) 1,000 to 50,000 B) 50,000 to 150,000 C) 500,000 to 1,000,000 D) 10,000,000 to 100,000,000 E) 5 billion to 10 billion

D

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.) A) 6 B) 18 C) 128 D) 512 E) 1,024

D

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%? A) 2,700,000 B) 5,500,000 C) 303,000,000 D) 304,000,000 E) 2,710,800,000

D

23) Which of the following examples poses the greatest potential threat to biodiversity? A) replanting, after a clear cut, a monoculture of Douglas fir trees on land that consisted of old-growth Douglas fir, western cedar, and western hemlock B) allowing previously used farmland to go fallow and begin to fill in with weeds and then shrubs and saplings C) trapping and relocating large predators, such as mountain lions, that pose a threat as they move into areas of relatively dense human populations D) importing an Asian insect into the United States to control a weed that competes with staple crops E) releasing sterilized rainbow trout to boost the sport fishing of a river system that contains native brook trout

D

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? A) sunlight intensity B) precipitation C) day length D) ocean currents E) salinity

D

25) Which of the following conditions is the most likely indicator of a population in an extinction vortex? A) The population is geographically divided into smaller populations. B) The species in question is found only in small pockets of its former range. C) The effective population size of the species falls below 500. D) Genetic measurements indicate a loss of genetic variation over time. E) The population is no longer connected by corridors.

D

26) Which series is correctly layered from top to bottom in a tropical rain forest? A) ground layer, shrub/immature layer, under story, canopy, emergent layer B) canopy, emergent layer, under story, shrub/immature layer, ground layer C) canopy, under story, shrub/immature layer, emergent layer, ground layer D) emergent layer, canopy, under story, shrub/immature layer, ground layer E) emergent layer, under story, canopy, ground layer, shrub/immature layer

D

28) Generally speaking, deserts are located in places where air masses are usually A) tropical. B) humid. C) rising. D) descending. E) expanding.

D

29) Turnover of water in temperate lakes during the spring and fall is made possible by which of the following? A) warm, less dense water layered at the top B) cold, more dense water layered at the bottom C) a distinct thermocline between less dense warm water and cold, dense water D) the changes in the density of water as seasonal temperatures change E) currents generated by nektonic animals

D

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? A) The lake would be uniformly cold during the winter and summer. B) The lake would fail to freeze over in winter. C) An algal bloom of algae would result every spring. D) Lakes would suffer a nutrient depletion in surface layers. E) The pH of the lake would become increasingly alkaline.

D

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, dN/dt = rN , which of the factors accounts for the effect on the moose population? A) r B) N C) rN D) K E) dt

D

39) Species introduced by humans to new geographic locations A) are usually successful in colonizing the area. B) always spread because they encounter none of their natural predators. C) increase the diversity and therefore the stability of the ecosystem. D) can outcompete and displace native species for biotic and abiotic resources. E) are always considered pests by ecologists.

D

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 A) that there is selective predation on female mice. B) that female mice die before reproducing. C) that this habitat is a good place for mice to reproduce. D) that you are observing immigrant mice. E) that the breeding season is over.

D

4) Which of the following might be an investigation of microclimate? A) the effect of ambient temperature on the onset of caribou migration B) the seasonal population fluctuation of nurse sharks in coral reef communities C) competitive interactions between various species of songbirds during spring migration D) the effect of sunlight intensity on species composition in a decaying rat carcass E) the effect of different nitrogen applications on corn productivity

D

45) What is a critical load? A) the amount of nutrient augmentation necessary to bring a depleted habitat back to its former level B) the level of a given toxin in an ecosystem that is lethal to 50% of the species present C) the maximum abundance level of a particular species, beyond which additional numbers will degrade a habitat D) the amount of added nutrient that can be absorbed by plants without damaging ecosystem integrity E) the number of predators an ecosystem can support that effectively culls prey populations to healthy levels

D

46) 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

D

49) Studying species transplants is a way that ecologists A) determine the abundance of a species in a specified area. B) determine the distribution of a species in a specified area. C) develop mathematical models for distribution and abundance of organisms. D) determine if dispersal is a key factor in limiting distribution of organisms. E) consolidate a landscape region into a single ecosystem.

D

5) 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) competitive interaction between individuals of the same population. E) the concentration of nutrients within the population's range.

D

5) Which of the following provides the best evidence of a biodiversity crisis? A) the incursion of a non-native species B) increasing pollution levels C) decrease in regional productivity D) high rate of extinction E) climate change

D

50) This term refers to the reflecting and absorption of infrared radiation by atmospheric methane, carbon dioxide, and water. A) depletion of ozone layer B) acid precipitation C) biological magnification D) greenhouse effect E) eutrophication

D

51) Which climograph shows the climate for location 2? A) B B) C C) D D) F E) H

D

53) Which climograph shows the climate for location 4? A) A B) B C) C D) E E) G

D

53) Which curve best describes survivorship in a marine crustacean that molts? A) A B) B C) C D) D E) E

D

59) Which zone has the lowest biomass per unit of area? A) A B) B C) C D) D E) E

D

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? A) B) C) D) E)

D

62) One characteristic that distinguishes a population in an extinction vortex from most other populations is that A) its habitat is fragmented. B) it is a rare, top-level predator. C) its effective population size is much lower than its total population size. D) its genetic diversity is very low. E) it is not well adapted to edge conditions.

D

66) Which of the following is true with respect to oligotrophic lakes and eutrophic lakes? A) Oligotrophic lakes are more subject to oxygen depletion. B) Rates of photosynthesis are lower in eutrophic lakes. C) Eutrophic lake water contains lower concentrations of nutrients. D) Eutrophic lakes are richer in nutrients. E) Sediments in oligotrophic lakes contain larger amounts of decomposable organic matter.

D

68) Which of the following is characteristic of most terrestrial biomes? A) annual average rainfall in excess of 250 cm B) a distribution predicted almost entirely by rock and soil patterns C) clear boundaries between adjacent biomes D) vegetation demonstrating vertical layering E) cold winter months

D

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 A) a diagonal line, getting higher with each generation. B) an "S," increasing with each generation. C) an upside-down "U." D) a "J," increasing with each generation. E) an "S" that ends with a vertical line.

D

69) The oceans affect the biosphere in all of the following ways except A) producing a substantial amount of the biosphere's oxygen. B) removing carbon dioxide from the atmosphere. C) moderating the climate of terrestrial biomes. D) regulating the pH of freshwater biomes and terrestrial groundwater. E) being the source of most of Earth's rainfall.

D

73) Based on current growth rates, Earth's human population in 2012 will be closest to A) 2 million. B) 3 billion. C) 4 billion. D) 7 billion. E) 10 billion.

D

77) Which pair of terms most accurately describes life history traits for a stable population of wolves? A) semelparous, r-selected B) semelparous, K-selected C) iteroparous, r-selected D) iteroparous, K-selected E) iteroparous, N-selected

D

9) Which of the following groups is most threatened by global extinctions? A) mammals B) birds C) fish D) amphibians E) plants

D

Use the following diagram from the text showing the spread of the cattle egret, Bubulcus ibis, since its arrival in the New World, to answer the following question. 61) How would an ecologist likely explain the expansion of the cattle egret? A) The areas to which the cattle egret has expanded have no cattle egret parasites. B) Climatic factors, such as temperature and precipitation, provide a suitable habitat for cattle egrets. C) There are no predators for cattle egrets in the New World, so they continue to expand their range. D) A habitat left unoccupied by native herons and egrets met the biotic and abiotic requirements of the cattle egret transplants and their descendants. E) The first egrets to colonize South America evolved into a new species capable of competing with the native species of herons and egrets.

D

it is the next "frontier" for feeding humanity. B) Because it is so immense, the pelagic ocean biome is globally uniform. C) Globally, more photosynthesis occurs in the ocean neritic biome than in the pelagic biome. D) Pelagic ocean photosynthetic activity is disproportionately low in relation to the size of the biome. E) The most abundant animals are vertebrate fishes.

D

1) "How do seed-eating animals affect the distribution and abundance of the trees?" This question A) would require an elaborate experimental design to answer. B) would be difficult to answer because a large experimental area would be required. C) would be difficult to answer because a long-term experiment would be required. D) is one that a present-day ecologist would be likely to ask. E) All options are correct.

E

11) In mountainous areas of western North America, north-facing slopes would be expected to A) receive more sunlight than similar southern exposures. B) be warmer and drier than comparable southern exposed slopes. C) consistently be steeper than southern exposures. D) support biological communities similar to those found at lower elevations on similar south-facing slopes. E) support biological communities similar to those found at higher elevations on similar south-facing slopes.

E

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 A) the elimination of tides. B) an increase in the length of night. C) an increase in the length of a year. D) a decrease in temperature at the equator. E) the elimination of seasonal variation.

E

14) Which of the following choices would most likely promote random distribution? A) territorial species B) species that secrete chemicals to attract or inhibit other individuals C) flocking and schooling behaviors D) spacing during the breeding season E) homogeneous chemical and physical factors in the environment

E

16) Which of the following environmental features might influence microclimates? A) forest canopy B) freshly plowed field C) log on the forest floor D) large boulder E) All of the options are correct.

E

17) Introduced species can have deleterious effects on biological communities by A) preying on native species. B) competing with native species for food or light. C) displacing native species. D) competing with native species for space or breeding/nesting habitat. E) All of the options are correct.

E

17) Which of the following is the most important assumption for the capture-recapture method to estimate the size of wildlife populations? A) All females in the population have the same litter size. B) More individuals emigrate from, as opposed to immigrate into, a population. C) Over 50% of the marked individuals need to be trapped during the recapture phase. D) There is a 50:50 ratio of males to females in the population before and after trapping and recapture. E) Marked individuals have the same probability of being recaptured as unmarked individuals during the recapture phase.

E

20) The greatest cause of the biodiversity crisis, the one which includes all of the others, is A) pollution. B) global warming. C) habitat destruction. D) introduced species. E) human overpopulation.

E

27) What is the limiting factor for the growth of trees in the tundra? A) low precipitation B) cold temperatures C) insufficient minerals in bedrock D) pH of soils E) permafrost

E

28) If the sex ratio in a population is significantly different from 50:50, then which of the following will always be true? A) The population will enter the extinction vortex. B) The genetic variation in the population will increase over time. C) The genetic variation in the population will decrease over time. D) The effective population size will be greater than the actual population size. E) The effective population size will be less than the actual population size.

E

29) 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 and population size D) gene flow between geographically separated populations E) All of the options are correct.

E

32) Natural selection involves energetic trade-offs between A) choosing how many offspring to produce over the course of a lifetime and how long to live. B) producing large numbers of gametes when employing internal fertilization versus fewer numbers of gametes when employing external fertilization. C) the emigration of individuals when they are no longer reproductively capable or committing suicide. D) increasing the number of individuals produced during each reproductive episode with a corresponding decrease in parental care. E) high survival rates of offspring and the cost of parental care.

E

35) Pacific salmon and annual plants are excellent examples of A) cohort disintegration. B) dispersion. C) Allee effect. D) iteroparous reproduction. E) semelparous reproduction.

E

47) 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) coniferous forest

E

47) Which of the following was the most significant limiting factor in human population growth in the 20th century? A) famine B) non-HIV disease C) HIV D) genocide E) clean water

E

48) Burning fossil fuels releases oxides of sulfur and nitrogen. These air pollutants can be responsible for A) the death of fish in lakes. B) precipitation with a pH as low as 3.0. C) calcium deficiency in soils. D) direct damage to plants by leaching nutrients from the leaves. E) All of the options are correct.

E

48) Trees are not usually found in the tundra biome because of A) insufficient annual precipitation. B) acidic soils. C) extreme winter temperatures. D) overbrowsing by musk ox and caribou. E) permafrost.

E

51) This is caused by excessive nutrient runoff into aquatic ecosystems. A) depletion of ozone layer B) acid precipitation C) biological magnification D) greenhouse effect E) eutrophication

E

57) Study the information above about quail habitats. Assuming that only one quail can occupy a habitat where all cover requirements are met, what is the maximum number of quail that could inhabit any of the hypothetical plots shown? A) 1 B) 2 C) 4 D) 6 E) 9

E

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? A) B) C) D) E)

E

61) Your friend is wary of environmentalists' claims that global warming could lead to major biological change on Earth. Which of the following statements can you use in response to your friend's suspicions? A) We know that atmospheric carbon dioxide has increased over the past 150 years. B) Through measurements and observations, we know that CO2 levels and temperature fluctuations are directly correlated, even in prehistoric times. C) Global warming could have significant effects on agriculture in the United States. D) Sea levels will likely rise, displacing as much as 50% of the world's human population. E) All statements listed could be used.

E

64) What is the single greatest threat to biodiversity? A) overharvesting of commercially important species B) introduced species that compete with native species C) pollution of Earth's air, water, and soil D) disruption of trophic relationships as more and more prey species become extinct E) habitat alteration, fragmentation, and destruction

E

66) In terms of demographics, which country is likely to experience the greatest population growth problem over the next ten years? A) Mexico, because there are fewer pre-reproductive individuals in their population B) China, whose population is more than a billion, but whose expected fertility rate is 1.8 children C) Germany, where the growth rate of the population is 0.1% per year D) United States (2009 population ~ 205,000,000, where 200,000 Americans are added to the population each day) E) Afghanistan, with a 3.85 annual growth rate

E

67) Which of the following biomes is correctly paired with the description of its climate? A) savanna-low temperature, precipitation uniform during the year B) tundra-long summers, mild winters C) temperate broadleaf forest-relatively short growing season, mild winters D) temperate grasslands-relatively warm winters, most rainfall in summer E) tropical forests-nearly constant day length and temperature

E

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? A) Seasons would be longer and more distinct (colder winters and warmer summers). B) There would be a smaller range between daytime high and nighttime low temperatures. C) Large scale weather events such as tornadoes and hurricanes would no longer be a part of regional climates. D) Winter seasons in both the northern and southern hemispheres would have more abundant and frequent precipitation events. E) The climate would stay the same. The only change would be longer days and nights.

E

9) Which of the following assumptions have to be made regarding the capture-recapture estimate of population size? I. Marked and unmarked individuals have the same probability of being trapped. II. The marked individuals have thoroughly mixed with the population after being marked. III. No individuals have entered or left the population by immigration or emigration, and no individuals have been added by birth or eliminated by death during the course of the estimate. A) I only B) II only C) I and II only D) II and III only E) I, II, and III

E

Use the survivorship curves in Figure 53.1 to answer the following questions. Figure 53.1 51) Which curve best describes survivorship in marine molluscs? A) A B) B C) C D) D E) E

E

therefore, this curve could not happen in nature.

E