Chapter 52-54

The symbols +, -, and 0 are to be used to show the results of interactions between individuals and groups of individuals. The symbol + denotes a positive interaction, - denotes a negative interaction, and 0 denotes where individuals are not affected by interacting. The first symbol refers to the first organism mentioned. What interactions exist between cellulose-digesting organisms in the gut of a termite and the termite? A) +/+ B) +/0 C) +/- D) 0/0

A) +/+

The symbols +, -, and 0 are to be used to show the results of interactions between individuals and groups of individuals. The symbol + denotes a positive interaction, - denotes a negative interaction, and 0 denotes where individuals are not affected by interacting. The first symbol refers to the first organism mentioned. What interactions exist between mycorrhizae and evergreen tree roots? A) +/+ B) +/0 C) +/- D) 0/0

A) +/+

magine five forest communities, each with one hundred 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

A) 25W, 25X, 25Y, 25Z

Which of the following statements about human populations in industrialized countries is incorrect? A) Birth rates and death rates are high. B) Average family size is relatively small. C) The population has undergone the demographic transition. D) The survivorship curve is Type I.

A) Birth rates and death rates are high.

Elephants are not the most abundant 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 are converted to forests or to shrublands. The newly growing forests support fewer species than the previous grasslands. Which of the following statements describes why elephants are the keystone species in this scenario? A) Elephants exhibit a disproportionate influence on the structure of the community relative to their abundance. B) Grazing animals depend upon the elephants to convert forests to grassland C) Elephants are the biggest herbivore in this community D) Elephants help other populations survive by keeping out many of the large African predators.

A) Elephants exhibit a disproportionate influence on the structure of the community relative to their abundance.

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 resulting uniform habitat supports stability, which in turn supports diversity. D) Less-competitive species evolve strategies to compete with dominant species.

A) Habitats are opened up for less competitive species.

Which of the following statements regarding turnover in a lake is correct? A) In fall turnover, dense water at 4°C sinks and disturbs sediments in the benthic zone. B) In fall turnover, dense water at 4°C rises and disturbs sediments in the benthic zone. C) The surface water gets to 4°C only by cooling. D) Fall turnovers and spring turnovers are exactly the same.

A) In fall turnover, dense water at 4°C sinks and disturbs sediments in the benthic zone.

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 its prey (P) population, but not vice versa? The arrows between species indicate a negative impact toward the population at the arrowhead. A) P ← C B) P → C C) C ↔ P D) P ← C → P

A) P ← C

Which of the following studies would shed light on the mechanism of spread of H5N1 virus from Asia to North America? 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.

A) Perform cloacal or saliva smears of migrating waterfowl to monitor whether any infected birds show up in Alaska.

Which of the following is responsible for the differences in summer and winter temperature stratification of deep temperate zone lakes? A) Water is most dense 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.

A) Water is most dense at 4°C.

In which of the following situations would you expect to find the largest number of r- selected individuals? A) a recently abandoned agricultural field in Colorado B) a sand dune community south of Lake Michigan C) an old-growth forest with large, mature trees D) a coral reef community off the coast of Mexico

A) a recently abandoned agricultural field in Colorado

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

A) an oligotrophic lake

Which of the following types of organisms is likely to have the widest geographic distribution? A) bacteria B) songbirds C) bears D) lizards

A) bacteria

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) convergent evolution B) allopatric speciation C) introgression D) gene flow

A) convergent evolution

An ecologist recorded 12 white-tailed deer, Odocoileus virginianus, per square kilometer (km2) in one woodlot and 20 km2 in another woodlot. What was the ecologist comparing? A) density B) dispersion C) carrying capacity D) range

A) density

During exponential growth, a population always ________. A) grows at its maximum per capita rate B) quickly reaches its carrying capacity C) adds more new individuals when the population is small than when it is large D) loses some individuals to emigration

A) grows at its maximum per capita rate

During exponential growth, a population always A) has a constant per capita population growth rate. B) quickly reaches its carrying capacity. C) cycles through time. D) loses some individuals to emigration.

A) has a constant per capita population growth rate.

As climate changes because of global warming, plant species' ranges in the northern hemisphere may move northward. The trees that are most likely to avoid extinction in such an environment are those that ________. A) have larger, more contiguous established populations to begin with B) produce well-provisioned seeds C) have seeds that become viable only after a forest fire D) disperse many seeds in close proximity to the parent tree

A) have larger, more contiguous established populations to begin with

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

A) in biomes at different latitudes

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

A) in biomes at different latitudes.

If an ecologist were studying the regional interactions among multiple populations of different species and how they influence the exchange of materials between their various environments, then this would be an example of which kind of research? A) landscape ecology B) population ecology C) global ecology D) ecosystem ecology

A) landscape ecology

A population's carrying capacity A) may change as environmental conditions change. B) can be accurately calculated using the logistic growth model. C) increases as the per capita population growth rate decreases. D) can never be exceeded.

A) may change as environmental conditions change.

In some circumstances, grasses that initially lose tissues from being consumed by animals such as elk or cattle regrow more than they would have otherwise, and benefit from the moderate levels of grazing. Which of the following terms would best describe such a plant-herbivore interaction? A) mutualism B) commensalism C) parasitism D) predation

A) mutualism

Which of the following traits 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

A) offspring with good chances of survival

Which of the following measurements would be most helpful in understanding the structure of an ecological community? I) determining how many species are present overall II) determining which particular species are present III) determining the kinds of interactions that occur among individuals of the same species IV) determining the abundance of resources available for one species A) only I and II B) only II and IV C) only I, II, and III D) I, II, III, and IV

A) only I and II

The ocean ecosystems affect the biosphere by ________. I) producing a substantial amount of the biosphere's oxygen II) adding carbon dioxide to the atmosphere III) being the source of most of Earth's rainfall IV) regulating the pH of freshwater biomes and terrestrial groundwater A) only I and III B) only II and IV C) only I, II, and IV D) only I, II, and III

A) only I and III

Which statements about dispersal are accurate? I) Dispersal is a common component of the life cycles of plants and animals. II) Colonization of devastated areas after floods or volcanic eruptions primarily depends upon climate. III) Seeds are important dispersal stages in the life cycles of most flowering plants. IV) Dispersal occurs only on an evolutionary time scale. A) only I and III B) only II and IV C) only I, II, and IV D) only II, III, and IV

A) only I and III

Scientific study of the population cycles of the snowshoe hare and its predator, the lynx, has revealed that A) predation is the dominant factor affecting prey population cycling. B) hares and lynx are so mutually dependent that each species cannot survive without the other. C) both hare and lynx population sizes are affected mainly by abiotic factors. D) the hare population is r-selected and the lynx population is K-selected.

A) predation is the dominant factor affecting prey population cycling.

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) lake trout, which seek out cold, deep water high in dissolved oxygen

A) red squirrels, who actively defend territories

The main reason polar regions are cooler than the equator is that ________. A) solar radiation strikes the poles at a lower angle and travels through more atmosphere B) the poles are farther from the sun than is the equator C) the polar atmosphere is thinner and contains fewer greenhouse gases D) the poles are permanently tilted away from the sun

A) solar radiation strikes the poles at a lower angle and travels through more atmosphere

Generalized global air circulation and precipitation patterns are caused by ________. A) solar radiation that warms moist air masses near the equator, which then cool and release precipitation as they rise, and then, at high altitude, move north or south of the tropics and sink back to the surface as dry air masses B) air masses that are dried and heated over continental areas, which then 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) solar radiation that warms dry air masses at the poles, causing them to sink toward the tropics, gain moisture, and then release it as precipitation.

A) solar radiation that warms moist air masses near the equator, which then cool and release precipitation as they rise, and then, at high altitude, move north or south of the tropics and sink back to the surface as dry air masses

Resource partitioning would be most likely to occur between ________. A) sympatric populations of species with similar ecological niches B) sympatric populations of a flowering plant and its specialized insect pollinator C) allopatric populations of the same animal species D) allopatric populations of species with similar ecological niches

A) sympatric populations of species with similar ecological niches

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

A) temperate broadleaf forest and grassland

Scientists interested in how populations interact within communities are attempting to determine the species diversity of an island under study. What kind of data would be most helpful to the scientists in determining diversity? A) the number of different species on the island and the size of the population of each species B) the number of species on the island that are consumers, producers, and decomposers C) the relative biomass of each species on the island separated by trophic level D) the number of trophic levels on the island and the niche of each species

A) the number of different species on the island and the size of the population of each species

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

A) tropical rain forest

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) one species of a non-venomous snake which rattles its tail to mimic a venomous rattlesnake

A) two species of unpalatable butterfly that have the same color pattern

The symbols +, -, and 0 are used to show the results of interactions between individuals and groups of individuals. The symbol + denotes a positive interaction, - denotes a negative interaction, and 0 denotes interactions in which individuals are not affected. The first symbol refers to the first organism mentioned. What interactions exist between a lion pride and African wild dogs, if the dogs are found to typically avoid areas with lions? A) +/+ B) +/- C) 0/0 D) -/-

B) +/-

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) 567,760,000 B) 304,657,600 C) 304,000,000 D) 2,657,600

B) 304,657,600

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. Using these birth and death rates, calculate an estimate of the total 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

B) 40 individuals added

The symbols +, -, and 0 are used to show the results of interactions between individuals and groups of individuals. The symbol + denotes a positive interaction, - denotes a negative interaction, and 0 denotes interactions in which individuals are not affected. The first symbol refers to the first organism mentioned. Which fact is correct when describing species interactions? A) +/0 will always remain such. B) A +/- interaction could shift to +/0 or +/+ over time, depending on other factors such as competition, population density, or environmental changes. C) Species interactions occur in isolation and cannot affect the structure of ecological communities. D) A -/- interaction benefits both of the species in the relationship.

B) A +/- interaction could shift to +/0 or +/+ over time, depending on other factors such as competition, population density, or environmental changes.

Which of the following examples demonstrate an ecological effect leading to an evolutionary effect? A) When seeds are not plentiful, trees produce more seeds. B) A few individuals with denser fur survive the coldest years of an ice age, and the offspring of the reproducing survivors of the ice age will likely have more dense fur. C) Fish that swim the fastest in running water catch the most prey and more easily escape predation. D) The insects that spend the most time exposed to sunlight have the most mutations from UV light, and thus evolve the fastest

B) A few individuals with denser fur survive the coldest years of an ice age, and the offspring of the reproducing survivors of the ice age will likely have more dense fur.

Which of the following scenarios would provide the most accurate 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-meter-square plots and extrapolate this number to the fraction of the study area these plots represent. C) Use the mark-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.

B) Count the number of pine trees in several randomly selected 10-meter-square plots and extrapolate this number to the fraction of the study area these plots represent.

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 cause 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.

B) Females undergo hormonal changes that delay sexual maturation, and many individuals suffer depressed immune systems and die due to the stress of overpopulation.

Which of the following statements is a likely explanation for why invasive species take over communities into which they have been introduced? A) Invasive species are less efficient 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 native species. C) Invasive species have a higher reproductive potential than native species. D) Invasive species come from geographically isolated regions, so when they are introduced to regions where there is more competition, they thrive.

B) Invasive species are not held in check by the predators and agents of disease that have always been in place for native species.

Which of the following investigations would shed the most light on the future 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 at the climatic changes that occurred since the last 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.

B) Look at the climatic changes that occurred since the last ice age and how species redistributed as glaciers melted, then make predictions on future distribution in species based on past trends.

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 humans has prevented certain communities, such as grasslands, from reaching their climax stage. D) Chaparral communities have evolved to the extent that they rarely burn.

B) Many kinds of plants and plant communities have adapted to frequent fires.

How might an ecologist test whether a species is occupying all of its fundamental niche or only a portion of it? A) Study the temperature range and humidity requirements of the species. B) Observe if the species expands its range after the removal of a competitor. C) Measure the change in reproductive success when the species is subjected to environmental stress. D) Observe if the niche size changes after the introduction of a similar non-native species.

B) Observe if the species expands its range after the removal of a competitor.

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 often "lean over" (that is, they are displaced from their normal vertical alignment). What is the most likely explanation for the unusual growth of these forests in this marginal habitat? A) Branches are adapted to absorb more carbon dioxide with this displaced alignment. B) Taproot formation is impossible, so trees developed shallow root beds. C) Trees are tilted so snow prevents them from breaking or tipping over. D) Trees tip so that they do not compete with each other for sunlight.

B) Taproot formation is impossible, so trees developed shallow root beds.

You observe two breeding female fish of the same species. One female lays 100 eggs and the other female lays 1,000 eggs. Which one of the following outcomes is most likely, given the limits of fitness trade-offs? A) The female laying 1,000 eggs breeds more often than the female laying 100 eggs. B) The female laying 100 eggs lives longer than the female laying 1,000 eggs. C) The eggs from the female laying 1,000 eggs have larger yolks than the yolks of the eggs from the female laying 100 eggs. D) The female laying 100 eggs is larger than the female laying 1,000 eggs.

B) The female laying 100 eggs lives longer than the female laying 1,000 eggs.

As N approaches K for a certain population, which of the following outcomes is predicted by the logistic equation? A) The population growth rate will not change. B) The population growth rate will approach zero. C) The population size will increase exponentially. D) The carrying capacity of the environment will increase.

B) The population growth rate will approach zero.

At 15-30°N, air masses formed over the Pacific Ocean are moved by prevailing westerlies, where they encounter extensive north-south mountain ranges. Which statement best describes the outcome of this encounter between a landform and an air mass? A) The cool, moist Pacific air heats as it rises, releasing its precipitation as it passes the tops of the mountains. This now warm and 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. This now cool and 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.

B) The warm, moist Pacific air rises and cools, releasing precipitation as it moves up the windward side of the range. This now cool and dry air mass heats up as it descends on the leeward side of the range.

What is the primary limiting factor that determines why no female animal can produce a very large number of very large eggs? A) Time is limited. B) There are energy constraints. C) Temperature constraints will prevent females from carrying too many eggs. D) There will be an increase in predation pressure if the females carry too many large eggs

B) There are energy constraints.

Long-term studies of Belding's ground squirrels show that immigrants move nearly 2 kilometers 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) These immigrants provide a source of genetic diversity for the other populations. C) Those individuals that emigrate to these new populations are looking for less crowded conditions with more resources. D) Gradually, the populations of ground squirrels will move from a clumped to a uniform population pattern of dispersion.

B) These immigrants provide a source of genetic diversity for the other populations.

Subtropical plants are commonplace in Land's End, England, whose latitude is the equivalent of Labrador in coastal Canada, where the local flora is instead subarctic. Which statement best explains why this apparent anomaly exists between North America and Europe? A) Labrador does not get enough rainfall to support the subtropical flora found in Land's End. B) Warm ocean currents interact with England, whereas cold ocean currents interact with Labrador. C) Rainfall fluctuates greatly in England; rainfall is consistently high in Labrador. D) Labrador receives sunlight of lower duration and intensity than does Land's End.

B) Warm ocean currents interact with England, whereas cold ocean currents interact with Labrador.

What would happen to the seasons if Earth were tilted 35 degrees off its orbital plane instead of the usual 23.5 degrees? A) The seasons would disappear. B) Winters and summers would be more severe. C) Winters and summers would be less severe. D) The seasons would be shorter.

B) Winters and summers would be more severe.

Which of the following is an example of Batesian mimicry? A) a butterfly that resembles a leaf B) a nonvenomous larva of a moth that moves like a venomous snake C) a fawn with fur coloring that camouflages it in the forest environment D) a snapping turtle that uses its tongue to mimic a worm, thus attracting fish

B) a nonvenomous larva of a moth that moves like a venomous snake

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

B) aphotic zone

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, nor are they negatively affected by this interaction. Which of the following best describes the interactions between dwarf mistletoes and trees? A) mutualism B) commensalism C) competition D) facilitation

B) commensalism

Based on current growth rates, Earth's human population in 2019 will be closest to A) 2.5 million. B) 4.5 billion. C) 7.5 billion. D) 10.5 billion.

C) 7.5 billion.

Some birds follow moving swarms of army ants in the tropics. As the ants march along the forest floor hunting insects and small vertebrates, birds follow and pick off any insects or small vertebrates that fly or jump out of the way of the ants. This situation is an example of what kind of species interaction between the birds and the ants? A) consumption B) commensalism C) parasitism D) mutualism

B) commensalism

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 affect the size of a population.

B) determine the birth rate and death rate of each group in a population.

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

B) immigration

A certain species of pine tree survives only in scattered locations at elevations above 2,800 meters in the western United States. To understand why this tree grows only in these specific places, an ecologist should ________. A) study the anatomy and physiology of this species B) investigate the various biotic and abiotic factors that are unique to high altitude C) analyze the soils found in the vicinity of these trees, looking for unique chemicals that may support their growth D) collect data on temperature, wind, and precipitation at several of these locations for a year

B) investigate the various biotic and abiotic factors that are unique to high altitude

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

B) is caused by pathogens that are transferred from other animals to humans by direct contact or by means of a vector

Character displacement differs from resource partitioning because character displacement ________. A) is a fundamental difference in feeding behaviors of individuals B) is directly linked to the evolution of genotypes that have allowed alternate resource use C) is a difference in the niche within a habitat that is preferred to be used by a species D) is not the result of competition

B) is directly linked to the evolution of genotypes that have allowed alternate resource use

Which of the following areas of study focuses on the exchange of energy, organisms, and materials between ecosystems? A) organismal ecology B) landscape ecology C) ecosystem ecology D) community ecology

B) landscape ecology

In deep water, which of the following abiotic factors would most limit primary productivity? A) temperature B) light availability C) solute concentration D) chemical composition of the sea floor

B) light availability

Which of the following statements about human population in industrialized countries are correct? I) Life history is r-selected. II) The population has undergone the demographic transition. III) The survivorship curve is Type III IV) Age distribution is relatively uniform. A) only I and III B) only II and Iv C) only I, II, and IV D) only II, III, and IV

B) only II and Iv

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) prey only on the least abundant species in the community

B) prey on the community's dominant species

Predators that are keystone species can maintain species diversity in a community if they A) competitively exclude other predators. B) prey on the community's dominant species. C) reduce the number of disruptions in the community. D) prey only on the least abundant species in the community.

B) prey on the community's dominant species.

Which of the following is an example of aposematic coloration? A) a non-poisonous snake mimics the color of a poisonous one B) the brightly colored patterns of monarch butterfly caterpillars C) green color of a plant D) a katydid whose wings look like a dead leaf

B) the brightly colored patterns of monarch butterfly caterpillars

Which of the following causes seasons on Earth? A) the variation in proximity of the Earth to the sun at different times of the year B) the constant tilt of the Earth, combined with its orbit around the sun C) the distance between the Earth and the sun in winter versus in the summer D) the variation or wobble of Earth's tilt during the year

B) the constant tilt of the Earth, combined with its orbit around the sun

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

B) the members of the population are competing for access to a resource.

The oak tree fungal pathogen, Phytophthora ramorum, has migrated 800 kilometers in 15 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

B) the mobility of their hosts

One 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) tropical regions have very high rates of immigration and very low rates of extinction

B) tropical regions generally have more available water and higher levels of solar radiation

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.

B) tropical regions generally have more available water and higher levels of solar radiation.

If the direction of Earth's rotation reversed, the most predictable effect would be ________. A) an elimination of deserts and increase in tropics B) winds blowing from west to east along the equator C) a loss of seasonal variation at high latitudes D) the elimination of ocean currents

B) winds blowing from west to east along the equator

If the direction of Earth's rotation reversed, the most predictable effect would be A) a big change in the length of the year. B) winds blowing from west to east along the equator. C) a loss of seasonal variation at high latitudes. D) the elimination of ocean currents.

B) winds blowing from west to east along the equator.

Suppose researchers marked 800 turtles and later were able to trap a total of 300 individuals in that population, of which 150 were marked. What is the estimate for total population size? A) 200 B) 1,050 C) 1,600 D) 2,100

C) 1,600

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 mark-recapture estimate, the lake trout population size could be closest to which of the following? A) 200 B) 400 C) 1,600 D) 80,000

C) 1,600

Approximately how many kilograms (kg) of carnivore (secondary consumer) biomass can be supported by a field plot containing 1000 kg of plant material? A) 1000 B) 100 C) 10 D) 1

C) 10

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) 59,850 D) 140,000

C) 59,850

Starting from a single individual, what is the size of a population of bacteria at the end of a 2-hour time period if they reproduce by binary fission every 20 minutes? (Assume unlimited resources and no mortality.) A) 16 B) 32 C) 64 D) 128

C) 64

Which of the following best describes the consequences of white-band disease in Caribbean coral reefs? A) Staghorn coral is decimated by the pathogen, and Elkhorn coral takes its place. B) Key habitat for lobsters, snappers, and other reef fishes improves. 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.

C) Algal species take the place of the dead coral, and the fish community is dominated by herbivores.

Recall that Clements's view of biological communities is that of a highly predictable and interrelated structure, while Gleason's view of biological communities is that individual species operate independently. If we set up many identical sterilized ponds in the same area and allowed them to be colonized, what result should we expect Gleason had a more accurate view of communities than did Clement's hypothesis? A) Identical plankton communities will develop in all ponds. B) Similar plankton communities will develop in all ponds. C) Different plankton communities will develop in all ponds. D) Limited plankton communities will develop in all ponds.

C) Different plankton communities will develop in all ponds.

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) The ability to disperse can expand the geographic distribution of a species.

C) Dispersal occurs only on an evolutionary time scale.

Which of the following statements is consistent with the principle of competitive exclusion? A) The random distribution of one competing species will have a positive impact on the population growth of the other competing species. B) If two species have the same fundamental niche, one will exclude the other competing species. C) Even a slight reproductive advantage will eventually lead to the elimination of the less well adapted of two competing species. D) Natural selection tends to increase competition between related species.

C) Even a slight reproductive advantage will eventually lead to the elimination of the less well adapted of two competing species.

Bouchard and Brooks studied the effect of insect flight on dispersal and speciation in rain forest insects. They sampled all of the insects in the study area and found that 60 insect species are flightless and 19 are able to fly. What can you conclude so far about this study?(P. Bouchard and D. R. Brooks. 2004. Effect of vagility potential on dispersal and speciation in rainforest insects. Journal of Evolutionary Biology 17:994-1006.) A) Flightless insects have a greater dispersal potential from this study area. B) Flightless insects are more numerous in the study area. C) Flightless insects have a higher species richness in the study area. D) Flightless insects are better suited for the tropics.

C) Flightless insects have a higher species richness in the study area.

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

C) Hosts in new environments have not had a chance to become resistant to the pathogen through natural selection.

In terms of community ecology, why are pathogens often more virulent now than in the past? 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 into new habitats (or communities) at an unprecedented rate. D) Medicines for treating pathogenic disease are in short supply.

C) Human activities are transporting pathogens into new habitats (or communities) at an unprecedented rate.

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 fail to freeze over in winter. B) An algal bloom of algae would result every spring. C) Lakes would suffer a nutrient depletion in surface layers. D) The pH of the lake would become increasingly alkaline.

C) Lakes would suffer a nutrient depletion in surface layers.

Which of the following statements can be accurately made about light in aquatic environments? A) Water equally reflects and absorbs all wavelengths of light. B) Longer wavelengths penetrate to greater depths. C) Light penetration largely limits the distribution of photosynthetic species. D) Most photosynthetic organisms avoid the surface where the light is too intense.

C) Light penetration largely limits the distribution of photosynthetic species.

Treehoppers (a type of insect) produce honeydew, which ants use for food. Treehoppers have a major predator, the jumping spider. Researchers hypothesized that the ants would protect the treehoppers from the spiders. During a one-year study, researchers found no difference in treehopper populations in any of their control and experimental groups. What could they measure during the second year to gain information about why this might have occurred? A) Measure the number of ant females. B) Measure the relative sizes of the treehoppers. C) Measure the relative abundance of jumping spiders. D) Measure the relative sizes of different ant species.

C) Measure the relative abundance of jumping spiders.

For mountain ranges that are subjected to prevailing winds, why is the climate drier on the leeward (downwind) side? A) Deserts create dry conditions 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 drier 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.

C) Pushed by the prevailing winds on the windward side, air is forced to rise, cool, condense, and drop its precipitation, leaving drier air to descend the leeward side.

Which of the following is a correct statement about MacArthur and Wilson's island equilibrium model? A) As the number of species on an island increases, the emigration rate decreases. B) Competitive exclusion is less likely on an island that has large numbers of species. C) Small islands receive few new immigrant species. D) Islands closer to the mainland have higher extinction rates.

C) Small islands receive few new immigrant species.

Use the diagram showing the spread of the cattle egret, Bubulcus ibis, since its arrival in the New World, to answer the question. The range of cattle egrets has expanded between 1937 and today. How would an ecologist likely best explain the expansion of the cattle egret? A) Climatic factors, such as sunlight, temperature, and precipitation, provide a suitable habitat for cattle egrets. B) There are no predators for cattle egrets in the New World, so they continue to expand their range. C) The abundant area and little competition with other birds occupying similar habitats met the biotic and abiotic requirements of the cattle egret expansion. D) The first egrets to colonize South America evolved into a new species capable of competing with the native species of herons and egrets.

C) The abundant area and little competition with other birds occupying similar habitats met the biotic and abiotic requirements of the cattle egret expansion.

Which of the following is a widely supported explanation for the tendency of tropical communities to have greater species diversity than temperate or polar communities? A) There are fewer parasites to negatively affect the health of tropical communities. B) Tropical communities are low in altitude, whereas temperate and polar communities are high in altitude. C) Tropical communities have higher sunlight and precipitation, and are generally older than temperate or polar communities. D) More competitive dominant species have evolved in temperate and polar communities.

C) Tropical communities have higher sunlight and precipitation, and are generally older than temperate or polar communities.

Uniform spacing patterns in plants such as the creosote bush are most often associated with ________. A) patterns of high humidity B) the random distribution of seeds C) competitive interaction between individuals of the same population D) the concentration of nutrients within the population's range

C) competitive interaction between individuals of the same population

Which of the following biomes spans the largest annual mean temperature range, but the narrowest mean precipitation range? A) tropical forest B) temperate forest C) desert D) taiga

C) desert

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

C) determine if dispersal is a key factor in limiting distribution of organisms

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 and the other two species had a lower relative abundance. A possible factor contributing to the abundances of these species in this example of secondary succession is ________. A) equilibrium B) immigration C) inhibition D) parasitism

C) inhibition

According to the island equilibrium model, species richness would be greatest on an island that is A) large and remote. B) small and remote. C) large and close to a mainland. D) small and close to a mainland.

C) large and close to a mainland.

Consider two old-growth forests: One is undisturbed while the other is being logged. In which region 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

C) logged, because the disturbed forest affords more resources for increased specific populations to grow

Which of the following examples would most accurately measure the dispersion of a population being studied? A) counting the number of times a one-kilometer transect is intersected by tracks of red squirrels after a snowfall B) measuring the distance between several burrows within a large prairie dog colony in a grassland C) measuring the average distance between individuals and their nearest neighbor, and then analyzing the variation and comparing those measurements at larger scales D) counting the number of zebras from airplane census observations

C) measuring the average distance between individuals and their nearest neighbor, and then analyzing the variation and comparing those measurements at larger scales

Based on the intermediate disturbance hypothesis, a community's species diversity is increased by ________. A) frequent immigrations of new species B) stable conditions with no disturbance C) moderate levels of disturbance D) intensive disturbance by humans

C) moderate levels of disturbance

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.

C) moderate levels of disturbance.

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 energy passes to the next higher level. D) most producers are inedible.

C) most of the energy in a trophic level is lost as energy passes to the next higher level.

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

C) most of the energy in a trophic level is lost as it passes to the next higher level

Which statements about K are correct? I) K varies among populations. II) K varies in space. III) K varies in time. IV) K is constant for any given species. A) only I and III B) only II and IV C) only I, II, and III D) only II, III, and IV

C) only I, II, and III

Which of the following statements regarding the future of populations in developing, less industrialized countries are correct? I) The reproductive rates are predicted to remain below replacement level. II) Survivorship will increase. III) Overall population size will increase dramatically. IV) The fertility rate is predicted to remain high, especially in some regions. A) only I and III B) only II and IV C) only II, III, and IV D) only I, II, and III

C) only II, III, and IV

Which of these environmental factor(s) is/are the key determining factor(s) that control(s) the biotic structure of aquatic biomes? A) average annual air temperature and precipitation B) seasonal fluctuation of water temperature C) oxygen concentrations and nutrient levels D) salinity

C) oxygen concentrations and nutrient levels

According to the logistic growth equation, dN/dt= rN(K-N)/K , ________. 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

C) population growth is zero when N equals K

According to the logistic growth equation below, dN/dt = rN (K-N)/K A) the number of individuals added per unit time is greatest when N is close to zero. B) the per capita population growth rate increases as N approaches K. C) population growth is zero when N equals K. D) the population grows exponentially when K is small.

C) population growth is zero when N equals K.

Wetlands are standing bodies of freshwater, just like lakes and ponds. However, wetlands are different from lakes and ponds because wetlands have ________. A) emergent vegetation B) oxygen-poor water C) shallow water and emergent vegetation D) emergent vegetation and oxygen-poor water

C) shallow water and emergent vegetation

According to the island equilibrium model, species richness would be lowest 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

C) small and remote

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) tundra B) savanna C) temperate broadleaf forest D) temperate grassland

C) temperate broadleaf forest

The success of plants extending their range northward following glacial retreat is primarily determined by ________. A) whether there is simultaneous migration of herbivores B) their tolerance to shade C) their seed dispersal rate D) their tolerance to cooler temperatures

C) their seed dispersal rate

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) two species that have exactly the same niche cannot coexist in a community. D) two species will stop reproducing until one species leaves the habitat.

C) two species that have exactly the same niche cannot coexist in a community.

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

C) vegetation demonstrating vertical layering

Coral reefs occur on the southeast coast of the United States but not at similar latitudes on the southwest coast. Differences in which of the following most likely account for this? A) air temperatures driven by precipitation B) day length C) water temperatures driven by ocean currents D) salinity differences

C) water temperatures driven by ocean currents

Which aquatic biome listed here is one of the most productive on Earth, and why? A) deep-sea vent, warm water temperatures B) coral reef, diversity of organisms C) wetlands, nutrient rich high-moisture soils D) oligotrophic lake, clear water for light penetration

C) wetlands, nutrient rich high-moisture soils

In the accompanying life table of a hypothetical population, what are the missing values for lx (y and z)? lx = the proportion alive at the start of year (age specific survivorship rate). A) y = 0.5, z = 0.5 B) y = 1.0, z = 0.5 C) y = 0.5, z = 0.1 D) y = 1.0, z = 0.2

C) y = 0.5, z = 0.1

Organisms evolve over generations to become adapted to the environmental conditions to which they are exposed. The diversity of organisms that occurs in any particular area thus may be largely determined by the abiotic factors limiting survivorship and reproduction of organisms in a region. Which of the following limit the range of Saguaro cactus in North America? I) pollinators II) sunlight III) precipitation IV) temperature A) only I and III B) only II, III, and IV C) only I, III, and IV D) I, II, III and IV

D) I, II, III and IV

Which of the following assumptions must be made regarding the mark-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) I, II, and III

D) I, II, and III

Which of the following studies would a community ecologist undertake to learn about competitive interactions? I) selectivity of nest sites among cavity-nesting songbirds II) the grass species preferred by grazing pronghorn antelope and bison III) stomach analysis of brown trout and brook trout in streams where they coexist A) only I and II B) only I and III C) only II and III D) I, II, and III

D) I, II, and III

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(K-N)/K which of the factors accounts for the effect of the moose population? A) r B) N C) rN D) K

D) K

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

D) Marked individuals have the same probability of being recaptured as unmarked individuals during the recapture phase.

A fish swimming into an estuary from a river would have which of the following as its greatest physiological challenge? A) The high water flow would make the fish expend more energy. B) The low oxygen content would give the fish difficulty in swimming aerobically. C) The temperature change would stress the fish by denaturing its proteins. D) The change in water solute content would challenge the osmotic balance of the fish.

D) The change in water solute content would challenge the osmotic balance of the fish.

In the hypothesis that Chthamalus stellatus (a species of barnacle) is competitively excluded from the lower intertidal zone by Balanus balanoides (another species of barnacle), what could be concluded about the two species? A) The fundamental and realized niches of B. balanoides and C. stellatus are identical. B) The fundamental and realized niches of B. balanoides and C. stellatus are different. C) The fundamental and realized niches of B. balanoides are different, but the fundamental and realized niches of C. stellatus are identical. D) The fundamental and realized niches of B. balanoides are identical, but the fundamental and realized niches of C. stellatus are different.

D) The fundamental and realized niches of B. balanoides are identical, but the fundamental and realized niches of C. stellatus are different.

Red-cheeked salamanders are partially protected from predators because of cardiac glycosides they produce from glands on their back. When ingested, cardiac glycosides disrupt normal heart rhythms. A different salamander species, the imitator salamander, also has red cheek patches, but does not produce cardiac glycosides. It does gain protection from predators that have learned to avoid red-cheeked salamanders. How does this relationship affect the population dynamics of both species? A) Both species are negatively affected. B) Both species are positively affected. C) The red-cheeked salamander is positively affected; the imitator is negatively affected. D) The red-cheeked salamander is not affected; the imitator is positively affected.

D) The red-cheeked salamander is not affected; the imitator is positively affected.

What would be the effect on climate in the temperate 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) Large-scale weather events such as tornadoes and hurricanes would no longer be a part of regional climates. C) Winter seasons in both the northern and southern hemispheres would have more abundant and frequent precipitation events. D) There often would be a larger range between daytime high and nighttime low temperatures.

D) There often would be a larger range between daytime high and nighttime low temperatures.

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. After doing some research to determine what might be an appropriately sized founding population, you reintroduce them. You then watch the population increase for several generations, and graph the number of individuals (vertical axis) against the number of generations (horizontal axis). With no natural predators impacting the population, the graph will likely appear as ________. A) a diagonal line, getting higher with each generation B) an "S" that ends with a vertical line C) an upside-down "U" D) a "J," increasing with each generation

D) a "J," increasing with each generation

There are more species in tropical areas than in places more distant from the equator. This is probably a result of ________. A) fewer predators and parasites B) more dispersed annual solar radiation compared to the poles C) more frequent ecological disturbances over a longer time span D) a longer time frame without disturbances for evolution and speciation

D) a longer time frame without disturbances for evolution and speciation

Which of the following is an example of a commensalism? A) fungi residing in plant roots, such as endomycorrhizae B) bacteria fixing nitrogen on the roots of some plants C) rancher ants that protect aphids in exchange for sugar-rich honeydew D) cattle egrets eating insects stirred up by grazing bison

D) cattle egrets eating insects stirred up by grazing bison

According to the nonequilibrium model of community diversity, ________. A) community structure remains stable in the absence of interspecific competition B) communities are assemblages of closely linked species that are permanently changed by disturbance C) interspecific interactions induce changes in community composition over time D) communities are constantly changing after being influenced by disturbances

D) communities are constantly changing after being influenced by disturbances

Which of the following causes populations to shift most quickly from an exponential to a logistic population growth? A) favorable climatic conditions B) removal of predators C) decreased death rate D) competition for resources

D) competition for resources

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) how sea-level changes affect barnacle distribution D) competitive exclusion and distribution of barnacle species

D) competitive exclusion and distribution of barnacle species

Generally speaking, deserts are located in places where air masses are usually ________. A) tropical B) ascending C) at the start of trade winds D) descending

D) descending

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

D) effect of grazing intensity by bison on plant species diversity

If two species are close competitors, and one species is experimentally removed from the community, the remaining species would be expected to ________. A) change its fundamental niche B) decline in abundance C) become the target of specialized parasites D) expand its realized niche

D) expand its realized niche

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) increasing the number of individuals produced during each reproductive episode and a corresponding decrease in parental care D) high survival rates of offspring and the cost of parental care

D) high survival rates of offspring and the cost of parental care

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 among various species of songbirds during spring migration D) how sunlight intensity affects plant community composition in the zone where a forest transitions into a meadow

D) how sunlight intensity affects plant community composition in the zone where a forest transitions into a meadow

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

D) iteroparous; K-selected

Which of the following is the best natural example of a uniform pattern of dispersion? A) bees collecting pollen in a wildflower meadow B) moss spores floating in the wind to new locations of a forest C) territorial songbirds in a mature forest during mating season D) mushrooms growing on the floor of an old growth forest

D) mushrooms growing on the floor of an old growth forest

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.

D) regulating the pH of freshwater biomes and terrestrial groundwater.

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) resource partitioning

D) resource partitioning

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) support biological communities similar to those found at lower elevations on similar south- facing slopes D) support biological communities similar to those found at higher elevations on similar south- facing slopes

D) support biological communities similar to those found at higher elevations on similar south- facing slopes

In the region of the Rocky Mountains, imagine that one local variety of Ponderosa pine (Pinus ponderosa) predominantly occurs between 5,000-8,500 feet in elevation, where it can best tolerate temperatures and precipitation. If future climate change in this region causes the temperature to increase and rainfall to decrease, then which of the following changes might an ecologist predict about the variety's range? A) that variety will occur at lower elevations B) that variety will occur at higher elevations C) that variety will occur at lower elevations and/or lower latitudes D) that variety will occur at higher elevations and/or higher latitudes

D) that variety will occur at higher elevations and/or higher latitudes

Turnover of water in temperate lakes during the spring and fall is caused 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

D) the changes in the density of water as seasonal temperatures change

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

D) the ecological footprint of the United States is large because per capita resource use is high

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

D) the ecological footprint of the United States is large because per capita resource use is high.

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 a year C) a decrease in temperature at the equator D) the elimination of seasonal variation

D) the elimination of seasonal variation

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

D) trophic structure.

In creating global climate patterns, which of the following factors is the primary cause of all of the other factors that are listed? A) precipitation differences between tropical and polar regions B) global ocean currents C) global wind patterns D) variation in the heating of Earth's surface

D) variation in the heating of Earth's surface

Which of the following is an important feature of most terrestrial biomes? A) annual average rainfall in excess of 250 centimeters B) a distribution predicted almost entirely by rock and soil patterns C) clear boundaries between adjacent biomes D) vegetation demonstrating vertical layering

D) vegetation demonstrating vertical layering

If you conclude that vegetation at every point on Earth exactly resembles the predicted biome distribution in a climograph, then ________. A) you are ignoring human land use changes or impacts, which have highly altered many regions within biomes B) the biome spanning the smallest combined ranges in precipitation and temperature is the tundra C) the biome most sensitive (in danger) from global warming is the desert D) you are ignoring the fact that local differences in soil, elevation, or topography can result in considerably different plant communities that are embedded within named biomes

D) you are ignoring the fact that local differences in soil, elevation, or topography can result in considerably different plant communities that are embedded within named biomes