Chapter 54 Review Questions
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) energy availability. E) plant biomass and plant water content.
A
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
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 bottom-up model for ecosystem restoration. D) adjusting the population numbers of each of the trophic levels back to the numbers that they were before man started disturbing ecosystems. E) monitoring and adjusting the nutrient and energy flow through a community with new technologies.
A
Ecologists are particularly concerned about pathogens because A) human activities are transporting pathogens around the world at alarming rates. B) pathogens are evolving faster than ever before. C) host organisms are not coming up with defenses against pathogens. D) new technologies have allowed microbiologists to classify more new pathogens. E) pathogens that infect organisms at the community level will eventually infect human beings.
A
Elephants are not the most common species in African grasslands. The grasslands contain scattered woody plants, but they are kept in check by the uprooting activities of the elephants. Take away the elephants, and the grasslands convert to forests or to shrublands. The newly growing forests support fewer species than the previous grasslands. 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
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
How are matter and energy used in ecosystems? A) Matter is cycled through ecosystems; energy is not. B) Energy is cycled through ecosystems; matter is not. C) Energy can be converted into matter; matter cannot be converted into energy. D) Matter can be converted into energy; energy cannot be converted into matter. E) Matter is used in ecosystems; energy is not
A
Two barnacles, Balanus and Chthamalus, can both survive on the lower rocks just above the low-tide line on the Scottish coast, but only Balanus actually does so, with Chthamalus adopting a higher zone. Which of the following best accounts for this niche separation? A) competitive exclusion B) predation of Chthamalus by Balanus C) cooperative displacement D) primary succession E) mutualism
A
Which island would likely have the greatest species diversity?
A
Which island would likely have the lowest extinction rate?
A
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
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
Which of the following is considered by ecologists a measure of the ability of a community either to resist change or to recover to its original state after change? A) stability B) succession C) partitioning D) productivity E) competitive exclusion
A
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. C) Test domestic chickens and ducks worldwide after they have been slaughtered for human consumption for the presence of H5N1. 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
The species richness of a community refers to the A) complexity of the food web. B) number of different species. C) the bottom-heavy shape of the energy pyramid. D) relative numbers of individuals in each species. E) total number of all organisms.
B
There are more species in tropical areas than in places farther from the equator. This is probably a result of A) fewer predators. B) more intense annual isolation. C) more frequent ecological disturbances. D) fewer agents of disease. E) all of the above
B
Which letter represents an organism that could be a producer? A) A B) B C) C D) D E) E
B
Which of the following best describes resource partitioning? A) Competitive exclusion results in the success of the superior species. B) Slight variations in niche allow similar species to coexist. C) Two species can coevolve to share the same niche. D) Differential resource utilization results in the decrease in species diversity E) A climax community is reached when no new niches are available.
B
Which of the following describes the relationship between ants and acacia trees? A) parasitism B) mutualism C) inhibition D) facilitation E) commensalism
B
Which of the following describes the relationship between legumes and nitrogen-fixing bacteria? A) parasitism B) mutualism C) inhibition D) facilitation E) commensalism
B
Which of the following examples best describes an ecological community? A) The intraspecific competition of members of a brook trout population inhabiting a stream during a given year. B) The interactions of all the plant and animal species inhabiting a 2 hectare forest. C) The material cycling and energy transformations between the biotic and abiotic components of an open meadow. D) The various species of barnacles competing for resources in an intertidal zone. E) The interactions of the various plant and animal species of park, excepting the decomposers.
B
With a few exceptions, most of the food chains studied by ecologists have a maximum of how many links? A) 2 B) 3 C) 5 D) 10 E) 15
C
A species of fish is found to require a certain water temperature, a particular oxygen content of the water, a particular depth, a rocky substrate on the bottom, and a variety of nutrients in the form of microscopic plants and animals to thrive. These requirements describe its A) dimensional profile. B) ecological niche. C) prime habitat. D) resource partition. E) home base.
B
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
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, their offspring behave in the same manner. You have discovered an example of A) mutualism. B) character displacement. C) Batesian mimicry. D) facultative commensalism. E) resource partitioning
B
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
Historically, most ecological research on the community has focused on which of the following? A) mutualistic relationships and other positive interactions B) competition or predation between two different species C) parasite-host relationships D) commensalistic relationships E) herbivory interactions
B
In a tide pool, 15 species of invertebrates were reduced to eight after one species was removed. The species removed was likely a(n) A) community facilitator. B) keystone species. C) herbivore. D) resource partitioner. E) mutualistic organism.
B
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
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
Species richness increases A) as we increase in altitude in equatorial mountains. B) as we travel north from the South Pole. C) on islands as distance from the mainland increases. D) as depth increases in aquatic communities. E) as community size decreases.
B
The energetic hypothesis and dynamic stability hypothesis are explanations to account for A) plant defenses against herbivores. B) the length of food chains. C) the evolution of mutualism. D) resource partitioning. E) the competitive exclusion principle.
B
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) biodiversity increases as evapotranspiration decreases. E) tropical regions have very high rates of immigration and very low rates of extinction.
B
The oak tree pathogen Phytophthora ramorum has migrated 650 km in ten years. West Nile virus spread from New York State to 46 others states in five years. The difference in the rate of spread is probably related to A) how lethal each pathogen is. B) the mobility of their hosts. C) the fact that viruses are very small. D) innate resistance. E) dormancy viability.
B
Which of the following interactions can correctly be labeled coevolution? A) the tendency of coyotes to respond to human habitat encroachment by including pet dogs and cats in their diets B) a genetic change in a virus that allows it to exploit a new host, which responds to virus-imposed selection by changing its genetically controlled habitat preferences C) a genetic change in foxes that allows them to tolerate human presence (and food) D) the adaptation of cockroaches to human habitation E) the ability of rats to survive in a variety of novel environments
B
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 natives 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 natives. C) Humans always select which species will outcompete the 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
Which of the following is the most logical conclusion about the distribution of the two species of barnacle, Chthamalus and Balanus? A) Chthamalus and Balanus compete for the same types of food. B) Balanus is less able to resist desiccation than Chthamalus. C) Chthamalus prefers higher temperatures than Balanus. D) Balanus is a better osmoregulator that Chthamalus. E) Chthamalus is preyed upon more than Balanus by birds because of its size.
B
Which of the following members of a marine food chain occupies a similar tropic level to a grasshopper in a terrestrial food chain? A) phytoplankton B) zooplankton C) lobster D) sea lion E) shark
B
Which of the following terms best describes the interaction between termites and the protozoans that feed in their gut? A) commensalism B) mutualism C) competitive exclusion D) ectoparasitism E) endoparasitism
B
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, while 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) individualistic hypothesis
B
Zoonotic disease A) describes sub-organismal pathogens such as viruses, viroids, and prions. 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
According to the equilibrium model of island biogeography, species richness would be greatest on an island that is A) small and remote. B) large and remote. C) large and close to a mainland. D) small and close to a mainland. E) environmentally homogeneous.
C
Based on the intermediate disturbance hypothesis, a community's species diversity is A) increased by frequent massive disturbance. B) increased by stable conditions with no disturbance. C) increased by moderate levels of disturbance. D) increased when humans intervene to eliminate disturbance. E) increased by intensive disturbance by humans.
C
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 both heterotropic and autotrophic nutrition during dormancy.
C
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
Monarch butterflies are protected from birds and other predators but the cardiac glycosides they incorporate into their tissues are from eating milkweed when they were in their caterpillar stage of development. 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
The feeding relationships among the species in a community determine the community's A) secondary succession. B) ecological niche. C) trophic structure. D) species-area curve. E) species richness.
C
When lichens grow on bare rock, they may eventually accumulate enough organic material around them to supply the foothold for later rooted vegetation. These early pioneering lichens can be said to do what to the later arrivals? A) tolerate B) inhibit C) facilitate D) exclude E) concentrate
C
Which island would likely exhibit the most impoverished species diversity?
C
Which island would likely have the lowest immigration rate?
C
Which letter represents an organism that could be a primary consumer? A) A B) B C) C D) D E) E
C
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
Which of the following is a good description of an ecological niche? A) the "address" of an organism B) synonymous with an organism's specific trophic level C) how an organism uses the biotic and abiotic resources 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
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 non-venomous 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
Which of the following treatments would most likely create a healthy, biodiverse community out of an impoverished community? A) Decrease the number of top level predators. B) Eliminate some of the of pest species of trees and shrubs. C) Add plenty of nutrients to the soil. D) Add more predators. E) Reduce the number of primary producers.
C
Which of the following types of species interaction is correctly paired with its effects on the density of the two interacting populations? A) predation: as one increases, the other increases B) parasitism: both decrease C) commensalism: as one increases the other stays the same D) mutualism: both decrease E) competition: both increase
C
All of the following have been used by plants to avoid being eaten except A) possessing spines and thorns on stems and leaves. B) synthesis of chemical toxins, such as strychnine, nicotine, and tannins. C) producing chemicals that are distasteful to herbivores, such as cinnamon, cloves, and peppermint. D) producing tissues that have unappealing colors. E) synthesizing chemicals that can cause abnormal development in some insects that eat them.
D
Approximately how many kg of carnivore production can be supported by a field plot containing 2000 kg of plant material? A) 20,000 B) 2,000 C) 200 D) 20 E) 2
D
In a particular case of secondary succession, three species of wild grass all invaded a field. By the second season, a single species dominated the field. A possible factor in this secondary succession was A) equilibrium. B) facilitation. C) immigration. D) inhibition. E) mutualism.
D
Of the following zoonotic diseases, which is most applicable to study by a community ecologist? A) mad cow disease B) hantavirus C) AIDS D) avian flu E) trichinosis
D
The dominant species in a community is A) characterized by very large individuals with long lives. B) the best competitor in the community. C) the best predator in the community. D) the species that contributes the most biomass to the community. E) the most energetically efficient species in the community.
D
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
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
Which of the following describes a successional event in which one organism makes the environment more suitable for another organism? A) parasitism B) mutualism C) inhibition D) facilitation E) commensalism
D
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 density of one competing species will have a positive impact on the population growth of the other competing species. C) Two species with the same fundamental niche will exclude other competing species. D) Even a slight reproductive advantage will eventually lead to the elimination of the less well adapted of two competing species. E) Evolution tends to increase competition between related species.
D
You are most likely to observe primary succession in a terrestrial community when you visit a(n) A) tropical rain forest. B) abandoned field. C) recently burned forest. D) recently created volcanic island. E) recently plowed field.
D
According to the Shannon Diversity Index, which block would show the greatest diversity? A) 1 B) 2 C) 3 D) 4 E) 5
E
According to the nonequilibrium model, A) communities will remain in a mature state if there are no human disturbances. B) community structure remains constant 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.
E
Community ecologists would consider which of the following to be most significant in understanding the structure of an ecological community? A) determining how many species are present overall B) which particular species are present C) the kinds of interactions that occur among organisms of different species D) the relative abundance of species E) all of the above
E
Prairie dogs once covered the expanses of the Great Plains. Their grazing made the grass more nutritious for the huge herds of bison, and a variety of snakes, raptors, and mammals preyed on the rodents. In fact, the black-footed ferret (now endangered) specialized in prairie dog predation. Today, growing housing and agricultural developments have covered many prairie dog towns. Which of the following statements about prairie dogs is true? A) Their realized niche has expanded. B) They have a mutualistic relationship with bison. C) They are probably a poor candidate for keystone species. D) Their fundamental niche is changed. E) Their fundamental niche has expanded.
E
The sum total of an organism's interaction with the biotic and abiotic resources of its environment is called its A) habitat. B) logistic growth. C) biotic potential. D) carrying capacity. E) ecological niche.
E
Which letter represents an organism that could be a carnivore? A) A B) B C) C D) D E) E
E
Which of the following is an example of cryptic coloration? A) bands on a coral snake B) brown color of tree bark C) markings of a viceroy butterfly D) colors of an insect-pollinated flower E) a "walking stick" insect that resembles a twig
E
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 species of hardwood forest tree species D) stomach analysis of brown trout and brook trout in streams where they coexist E) All of the above would be appropriate studies of competitive interaction.
E