Biology Chapter 44 (Ecological Communities), CH37-COMMUNITY AND ECOSYSTEM ECOLOGY, test 5, BSC2011 Exam 3, Learning Catalytic's Ecology Section, Chapter 38, Exam 3 Multiple Choice, Chapter 54 Community Ecology, Chapter 37, Bio HW 6 (Ch. 38), Ch 54, C...

Ace your homework & exams now with Quizwiz!

About how much of the energy in the producers of an ecosystem will be available to secondary consumers in this ecosystem?

about 1%

Which marine zone is expected to have the lowest rates of primary productivity (photosynthesis)?

abyssal

Which marine zone would have the lowest rates of primary productivity (photosynthesis)?

abyssal

One reason it is important to understand community ecology is to

aid in conservation of endangered species.

The principle of _______ states that once an organism has acquired a unit of some resource, that bit of resource cannot be used for multiple functions at once.

allocation

Intraspecific competition refers to competition

among individuals of the same species

Habitats with many edges a. result in a significant increase in diversity. b. often result from human activities. c. are the result of natural disasters. d. favor animals that prefer large, open ranges.

Rachel Carson would most likely have endorsed which of the following statements? A) Conserving wildness will lead to the preservation of the Earth. B) The greatest liberty humans have taken is with nature. C) Humans have dominion over the Earth and all of its inhabitants. D) All pesticides are unsafe and must be banned. E) The environment can repair damage created by human activity.

Small areas that are home to a large number of threatened species and an exceptional concentration of species found nowhere else on Earth are called a. biologically magnified. b. biodiversity hot spots. c. endemic environments. d. exotic hot spots.

The main reason polar regions are cooler than the equator is because A) there is more ice at the poles. B) sunlight strikes the poles at an lower angle. C) the poles are farther from the sun. D) the poles have a thicker atmosphere. E) the poles are permanently tilted away from the sun.

Which of the following levels of organization is arranged in the correct sequence from most to least inclusive? A) community, ecosystem, individual, population B) ecosystem, community, population, individual C) population, ecosystem, individual, community D) individual, population, community, ecosystem E) individual, community, population, ecosystem

Which of the following is the equation for zero population growth (ZPG)?dN/dt = rN

b = m or r = 0

At Glacier Bay, Alaska, the gravel deposits left behind by a retreating glacier were colonized first by which of the following organisms? a. Mosses b. Microorganisms c. Trees d. Shallow-rooted herbs

b. Microorganisms

Productivity in a community _______ with increasing species number and _______ with an increase in the number of functional groups. a. increases; increases b. increases; decreases c. decreases; increases d. decreases; remains unchanged e. decreases; decreases

b. increases; decreases

The relatively thin layer on the earth's surface where life is possible is known as the

biosphere

All of Earth that is inhabited by life is called the

biosphere.

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

Captive breeding a. has advanced to the point where biologists believe it can be used to save most endangered species. b. is the main conservation technique used to try to save endangered species from extinction. c. has allowed for the re-introduction of many species to areas from which they had disappeared. d. can work for animals, but is generally not used for endangered plants.

Most biodiversity hot spots are found in ________ regions. a. temperate b. tundra c. tropical d. western

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

If N = 1000 in a population, and there are 40 births that year, and 60 deaths, what is the "r" for the population? (Hint: first calculate the per capita birth and death rates, then subtract b - d to get "r".) a. -0.2 b. 0.02 c. -0.02 d. 1.2

c. -0.02

The theory of island biogeography can be applied to oceanic islands as well as to other types of habitat islands. For which of these habitats, however, would it be least relevant? a. A coral reef split in half by dredging b. A national park surrounded by cities and suburbs c. A coastal area being recolonized after a hurricane d. A large nature preserve surrounded by farmland e. A tropical forest fragmented by deforestation to make farms

c. A coastal area being recolonized after a hurricane

Based on the theory of island biogeography, fragmentation should have the least effect when a. the total amount of habitat is much reduced. b. the size of patches is small. c. patches are close to one another. d. patches are far from one another. e. habitat area shrinks.

c. patches are close to one another.

What type of dispersion pattern is this? a. Clumped b. Random c. Uniform

c. uniform

An island is at equilibrium in terms of species richness when the a.extinction rate is zero regardless of the immigration rate. b.immigration rate is zero regardless of the extinction rate. c.immigration rate is equal to the extinction rate. d.immigration rate is greater than the extinction rate. e.extinction rate is slightly higher than the immigration rate.

c.immigration rate is equal to the extinction rate.

Carbon mainly cycles between the biotic and abiotic worlds through the processes of

cellular respiration and photosynthesis.

Ecology as a discipline directly deals with all of the following levels of biological organization except

cellular.

Mild, rainy winters and hot, dry summers are typical of which type of biome?

chaparral

One mechanism that prey populations evolve to avoid predation is

chemical defenses.

Which of the following is an invasive species? a. carrier pigeon in the continental United States b. mallard duck in the western United States c. elephant in India d. brown tree snake in Guam

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

Which type of biome would most likely occur in a climate with mild, rainy winters and hot, dry summers? A) desert B) taiga C) temperate grassland D) chaparral E) savanna

20) Starting from a single individual, what is the size of a population of bacteria that reproduce by binary fission every 20 minutes at the end of a 2-hour time period? (Assume unlimited resources and no mortality.) A) 6 B) 8 C)128 D) 512 E) 1,024

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

Which factor is NOT required in the definition of migration? A. Traveling long distances B. Returning to the starting point C. Traveling seasonally or annually D. Day-to-day movements to forage for food E. Remaining at a destination for a considerable time

D. Day-to-day movements to forage for food

The following question refers to the figure, which depicts the age structure of three populations. Which population(s) appear(s) to be stable?

III

A population with rapidly expanding exponential growth would be best represented by a graph with a(n) ______-shaped curve.

In general, the biomass in an ecosystem will be greatest at the trophic level comprising _____.

producers

Mutualism could be expressed by _____.

+/+

The per capita growth rate of a population of guppies is 0.07 per month. If the per capita birth rate is 0.12 per month, the per capita death rate is _______ per month.

0.05

In a population of 10000 organisms over a one year period there are 750 births and 130 deaths. Calculate the growth rate for that year.

0.062

Using the Levins model, what is the equilibrium proportion of patches occupied in a metapopulation with an extinction probability of 0.2 and a colonization probability of 0.5?

0.6

order the following greenhouse effect steps

1. Sun's energy hits the earth 2. energy is reflected back to the atmosphere 3. energy is absorbed by greenhouse gases 4. energy is redirected back to the Earth's surface 5. Earth's surface temperature heats up

rank the following reservoirs by the amount of nitrogen they store, starting with the largest reservoir

1. atmosphere 2. rock 3. ocean 4. soils 5. plant biomass 6. marine biomass

put the following events that create dead zones in the order in which the occur

1. increased runoff of nitrogen from the land to the ocean 2. increased phytoplankton growth 3. phytoplankton die and sink to the bottom of ocean 4. microbes breakdown dead phytoplankton 5. microbes absorb oxygen and release carbon dioxide 6. oxygen in the water is depleted 7. aquatic animals die

the percent of energy that is transferred from one trophic level to another is about

10%

A population of fungi in a yard produces 10 mushrooms in year 1, 20 in year 2, and 40 in year 3. If this trend continues, by year 5 there will be ________ mushrooms.

160

how many years does she have if it is growing multiplicatively with constant r?

2 years

In the population growth curve shown in the graph, the rate of growth is greatest at which point?

You are studying a population of chimps. There are a total of 23 individuals old enough to breed, 10 females and 13 males. Two dominant males, Ed and Bob, are bullies, and are the only breeding males. All females breed. What is the "effective population size" (Ne). 23 individuals 6.66 individuals 3.33 individuals You cannot tell from this information

6.66 individuals

1) A community is composed of A) potentially interacting populations of different kinds of organisms. B) one species of organism living in a specific environment on Earth. C) living organisms and their nonliving environment. D) the factors that constitute an organism's niche.

10) Camouflage typically evolves as a result of A) predation. B) interspecific competition. C) mutualism. D) herbivory.

11) One predator avoidance mechanism that has evolved in prey is A) chemical defenses. B) secretion of digestive enzymes that hydrolyze glucose. C) secretion of enzymes that break down toxic plant compounds. D) development of a short gestation period.

13) Most plants have a variety of chemicals, spines, and thorns because the plants A) cannot run away from herbivores. B) feed on the organisms that try to eat them. C) are camouflaged into their surroundings. D) must rely on photosynthesis for food.

14) In addition to abiotic factors, community composition of plants can be severely compromised by A) parasites and pathogens. B) introduction of chestnut trees. C) non-native birds. D) rapid coevolution.

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

23) A keystone species that is a predator will A) maintain the species diversity in a community. B) harvest prey species down to extinction. C) help many of its prey reproduce. D) reduce the diversity of the community.

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

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

29) One simple thing that you can do to help safeguard the environment is to eat a diet consisting only of organisms that are A) producers. B) primary consumers. C) secondary consumers. D) a mix of producers and consumers.

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

37) Which variables define the ecological life history of a species? A) the age at which reproduction begins, frequency of reproduction, and the number of offspring for each reproductive episode B) the ratio of females to males, the length of the breeding season, and the number of offspring for each reproductive episode C) the number of offspring produced over a lifetime by a breeding pair and the survivability of the offspring D) timing breeding sessions with optimal environmental conditions and the number of offspring produced during each breeding session E) the amount of parental care given after birth, the number of reproductive episodes per year, and the number of years females are capable of producing viable offspring

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

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

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

9) Dinoflagellates are important to coral and coral-dwelling animals because they A) produce energy that is used by coral animals through photosynthesis. B) provide shelter for the fast-growing seaweeds associated with coral. C) produce CO2 and nitrogen for coral. D) are toxic to species that prey on reef-dwelling fish.

A community is composed of A) potentially interacting populations of different kinds of organisms. B) one species of organism living in a specific environment on Earth. C) living organisms and their nonliving environment. D) the factors that constitute an organism's niche.

Based on the following graph, what is the most likely relationship between Paramecium and Didinium? a) Didinium prey on Paramecium b) Paramecium prey on Didinium c) Didinium and Paramecium have a mutualistic relationship d) Paramecium is a parasite that feeds on Didinium e) Paramecium have a commensal relationship with Didinium

Brown-headed cowbirds utilize fragmented forests effectively by a) parasitizing the nests of forest birds and feeding on open-field insects b) feeding on the fruits of shrubs that tend to grow at the forest/open-field interface c) outcompeting other songbird species in fragmented communities d) using forest cover to escape from predators in their normal grassland habitat e) roosting in forest trees and nesting in grassy fields

Conservation of critical parts of food webs is important because A. of the potential for trophic cascades. B. they increase ecological efficiency. C. they promote ecological transitions. D. of their role in succession. E. None of the above

Dinoflagellates are important to coral and coral-dwelling animals because they A) produce energy that is used by coral animals through photosynthesis. B) provide shelter for the fast-growing seaweeds associated with coral. C) produce CO2 and nitrogen for coral. D) are toxic to species that prey on reef-dwelling fish.

From the list below, select all the choices that are acceptable definitions of secondary production. a) chemical energy in food that is converted to new biomass by consumers b) energy converted by secondary consumers from primary consumers c) energy that is not used by consumers for growth and reproduction d) solar energy that is converted to chemical energy by photosynthesis e) growth that takes place during the second year of life in consumers

Given that CO2 is produced by respiration, why does the amount of CO2 in the atmosphere remain relatively constant? (When answering this question, exclude the impact of human activities on atmospheric CO2 .) A) CO2 is converted in photosynthesis to carbohydrates. B) CO2 is split apart during photosynthesis. C) CO2 mostly forms carbonate rocks. D) CO2 is trapped in dead organisms' bodies. E) CO2 is a buffer.

How are movement corridors potentially harmful to certain species? a) They spread disease and parasites. b) They increase inbreeding. c) They increase genetic diversity. d) They promote dispersion. e) They allow seasonal migration.

Many human activities reduce biodiversity. Which of the following examples poses the greatest potential threat to biodiversity? a) constructing oil and gas pipelines through old growth forest b) allowing previously used farmland to go fallow and begin to fill in with weeds and then shrubs and saplings c) replanting, after a clear cut, a monoculture of Douglas fir trees on land that consisted of old-growth Douglas fir, western cedar, and western hemlock d) lack of regulations to limit the harvest of the medicinal plant ginseng

Most plants have a variety of chemicals, spines, and thorns because the plants A) cannot run away from herbivores. B) feed on the organisms that try to eat them. C) are camouflaged into their surroundings. D) are adapted to attract herbivores. E) are relying upon Batesian mimicry.

Relatively small geographic areas with high concentrations of endemic species and a large number of endangered and threatened species are known as a) biodiversity hot spots b) movement corridors c) extinction vortices d) nature reserves

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

Skill: Knowledge/Comprehension 3) An ecologist recorded 2 white-tailed deer, Odocoileus virginianus, per square mile in one woodlot and 20 per square mile in another woodlot. What was the ecologist comparing? A) density B) dispersion C) carrying capacity D) cohorts E) range

The differentiation of niches that enables similar species to coexist in a community is called A) resource partitioning. B) the competitive exclusion principle. C) interspecific competition. D) niche competition. E) resource reduction.

The oak tree pathogen Phytophthora ramorum has migrated 800 km 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 mobility of their hosts. b) the fact that viruses are very small. c) dormancy viability. d) innate resistance. e) the lethality of each pathogen.

Which curve best describes survivorship in humans who live in developed nations?

Which of the following is most responsible for the biochemical diversity of plants, including those that produce compounds that humans use for spices? A. Evolutionary arms races with herbivores B. Adaptations to different soils C. Adaptations to different levels of moisture D. Evolutionary arms races with commensals E. Adaptations to different temperature regimes

Which of the following statements about habitat fragmentation is false? A. Human-dominated habitat surrounding patches increases the colonization rate of patches. B. Small isolated patches lose species more rapidly than larger isolated patches. C. Habitat fragmentation results in lower species richness in the fragments than in the original habitat. D. Isolated patches lose species more rapidly than patches of similar size that are near other patches. E. Connecting fragments with dispersal corridors enhances colonization.

Which of the following statements is accurate according to the nonequilibrium model? a) communities are constantly changing after being influenced by disturbances b) communities are assemblages of closely linked species that are irreparably changed by disturbance c) community structure remains stable in the absence of interspecific competition d) communities are less important than the individuals that compose them e) interspecific interactions induce changes in community composition over time

Which of these processes does not release carbon dioxide into the atmosphere? A) cellular respiration B) decomposition C) photosynthesis D) burning

Which one of the following statements about the phosphorus cycle is false? A) Consumers obtain phosphorus in organic form from plants. B) Phosphorus has its main abiotic reservoir in water. C) Plants absorb dissolved phosphorus ions in the soil. D) Phosphorus that drains from soils into the sea becomes part of new rock and will not cycle back into living organisms until geologic processes lift the rock up and expose it to weathering. E) Phosphates are a major component of sewage.

Which participant would receive an increase in its population growth rate from a given interspecific interaction? A resource in a consumer-resource interaction A consumer in a consumer-resource interaction A competitor in a competition interaction A participant in an amensal relationship None of the above

A consumer in a consumer-resource interaction

Which of the following examples of an ecological effect leading to an evolutionary effect is most correct?

A few individuals with denser fur survive the coldest days of an ice age, and the reproducing survivors of the ice age all have long fur.

What is likely to be the greatest challenge facing the zoned reserve systems of Costa Rica?

A growing human population

Based on the principle of allocation, which population of organisms would spend the highest percentage of its available energy on growth and reproduction (that is, would grow largest and have the most offspring)?

A population in normal climatic conditions with abundant resources

B) I and II only

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

Consider a population whose growth over a given time period can be described by the exponential model: dN/dt = rN. Select the correct statement about this population.

A population with a positive value of r will grow exponentially.

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

A) large and close to a mainland.

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) mutualism

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

How do seed-eating animals affect the distribution and abundance of the trees?

All options are correct.

A) density

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

Which of the following is NOT true?

As the human population increases in size, less energy but more material will be consumed.

Which of the following statements is false?

Asexually reproducing species tend to have higher rates of local extinction.

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

12) Some herbivore-plant interactions evolved through a series of reciprocal evolutionary adaptations in both species. This process is called A) herbivory. B) coevolution. C) selection. D) tropism.

16) In a hypothetical food chain consisting of grass, grasshoppers, sparrows, and hawks, the grasshoppers are A) primary consumers. B) primary producers. C) secondary consumers. D) secondary producers.

17) In a food chain consisting of phytoplankton → zooplankton → fish → fishermen, the fishermen are A) secondary consumers. B) tertiary consumers. C) quaternary consumers. D) secondary producers.

18) Organisms that digest molecules in organic material and convert them into inorganic forms are A) primary consumers. B) decomposers. C) primary producers. D) detritivores.

19) Which of the following accurately represents a food chain in the grasslands of Africa? A) grass, giraffes, lions, vultures, fungi B) grass, fungi, giraffes, vultures, lions C) grass, lions, giraffes, fungi, vultures D) grass, fungi, lions, vultures, giraffes

21) The number of species in a community is called the A) species diversity. B) species richness. C) species population. D) species index.

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

6) Which of the following is an example of predation? A) a lizard's camouflage B) a hawk swooping down quickly to capture, kill, and eat a prairie king snake C) a goldfinch feeding on the seeds of a thistle plant D) the vivid colors of the poison-arrow frog in Costa Rica

70) Population ecologists follow the fate of same-age cohorts to A) determine a population's carrying capacity. B) determine the birth rate and death rate of each group in a population. C) determine if a population is regulated by density-dependent processes. D) determine the factors that regulate the size of a population. E) determine if a population's growth is cyclic.

Elephants are not the most dominant species in African grasslands, yet they influence community structure. The grasslands contain scattered woody plants, but they are kept in check by the uprooting activities of the elephants. If the elephants are taken away, 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) Elephants prevent drought in African grasslands. b) Elephants exhibit a disproportionate influence on the structure of the community relative to their abundance. c) Grazing animals depend upon the elephants to convert forests to grassland. d) Elephants help other populations survive by keeping out many of the large African predators. e) Elephants are the biggest herbivore in this community.

If you mapped the pattern of spacing of humans in the Marquette Campus Ecosystem, you would most likely observe a) uniform spacing. b) clumped spacing. c) random spacing. d) staggered spacing. e) inverted spacing.

Per capita means A. per population. B. per individual. C. per community. D. per cohort. E. per family.

Question 4 1 / 1 point Of the choices listed below, select the one that causes all of the others in creating global terrestrial climates? a) the movement of land masses b) differential heating of Earth's surface c) global wind patterns d) evaporation of water from ocean surfaces e) ocean currents

Skill: Application/Analysis 8) A population of ground squirrels has an annual per capita birth rate of 0.06 and an annual per capita death rate of 0.02. Calculate an estimate of the number of individuals added to (or lost from) a population of 1,000 individuals in one year. A) 20 individuals added B) 40 individuals added C) 20 individuals added D) 400 individuals added E) 20 individuals lost

Some herbivore-plant interactions evolved through a series of reciprocal evolutionary adaptations in both species. The process is called A) herbivory. B) coevolution. C) selection. D) trophism.

To selectively remove soil toxins from regions affected by Hurricane Katrina, some residents are growing sunflowers and other plants in their yards. Once mature, the plants are pulled and safely stored with other contaminated wastes. This is an example of a) biological augmentation. b) bioremediation. c) arresting nutrient cycling. d) lowering production efficiency. e) hippies making problems worse.

Which of the following interspecific interactions has negative effects for both species involved? a) Parasitism b) Competition c) Amensalism d) Herbivory e) None of the above

8) Which of the following best describes resource partitioning?

B) Slight variations in niche allow similar species to coexist.

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) Slight variations in niche allow similar species to coexist.

10) Resource partitioning would be most likely to occur between

B) sympatric populations of species with similar ecological niches.

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

5) When a crocodile eats a fish, the interspecific interaction between the two could be expressed as ________ for the crocodile and ________ for the fish. A) -; - B) +; + C) +; - D) -; +

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

76) According to the logistic growth equation dN/dt = rmaxN (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. E) the birth rate (b) approaches zero as N approaches K.

A BIDE model of population growth is more applicable than a BD model for a population A. that follows logistic growth. B. that is shrinking. C. that is part of a metapopulation. D. in which reproduction occurs at regular intervals. E. None of the above

If left under otherwise natural conditions, which of the following ecosystems would quickly change into a different type if fire was suppressed? A) deciduous forest B) desert C) tallgrass prairie D) freshwater marsh E) None of the choices would change significantly.

In a certain ecosystem, field mice are preyed on by snakes and hawks. The entry of wild dogs into the system adds another predator of the mice. Of the following, the most likely short-term result of this addition is A) an increase in snake population. B) a tendency for hawks to prey on the dogs. C) a reduction in numbers of mice. D) migration of the hawks to another ecosystem.

In a food chain consisting of phytoplankton → zooplankton → fish → fishermen, the fishermen are A) primary consumers. B) secondary consumers. C) tertiary consumers. D) primary producers. E) secondary producers.

Jenny Jone's breast milk tested at 5 part per million DDT. Her two-year-old son Johnny Jones is still consuming breast milk. Which one of the following statements is TRUE? A) Johnny Jones had no DDT in his body because his little body was a metabolic dynamo for breaking down DDT. B) Johnny had about the same DDT concentration in his fat as his mother had in her milk. C) Johnny Jone's body at had a much higher concentration of DDT than did Jenny Jone's breast milk. D) Johnny Jones had a far lower concentration of DDT in his body fat than his mommy had in her breast milk.

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

Skill: Application/Analysis 7) To construct a reproductive table for a sexual species, one needs to A) assess sperm viability for the males in the population. B) keep track of all of the offspring of a cohort. C) keep track of the females in a cohort. D) keep track of all of the offspring of the females in a cohort. E) analyze the ratio of deaths to births in a cohort.

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

Which of the following is a primary producer? a) Spider b) Earthworm c) Oak tree d) Human e) None of the answers are correct

Which of the following types of species interaction is correctly paired with its effects on the density of the two interacting populations?

C) commensalism: as one increases the other stays the same

1) The feeding relationships among the species in a community determine the community's

C) trophic structure.

Artificially constructed movement corridors

Can be harmful because they allow for the spread of disease

Plants absorb most of the nutrients they need for growth and reproduction as ions dissolved in water. Which element do they obtain from air?

Carbon

According to this graph of changes in Earth's atmosphere, which change took place between the years 1800 and 2000?

Carbon dioxide (CO2) levels increased from 290 ppm to 380 ppm.

Which of the following statements about climate change and environmental cues is false?

Climate influences day length

The fecal matter from giraffes helps fertilize a particular species of plant, thus increasing the plant's ability to grow in a particular area. The plant has no effect on giraffes. The relationship between the giraffes and the plants is best described as

Commensalism

A study of metabolic rates in a terrestrial community showed that the energy released by respiration exceeded the energy captured in photosynthesis. Which of the following situations is most likely?

Community biomass is decreasing.

Which sequence represents the correct ranking, from smallest (least encompassing) to largest (most encompassing)?

Community, ecosystem, biosphere

In which relationship is the fitness of both participants negatively affected?

Competition

If the niches of two species are very similar, which of the following is true?

Competition between the two species will be severe.

An organism living in the climate depicted in the below Walter Climate diagram would most likely have the following adaptation(s) EXCEPT:

Concentrated urine

Which statement about coniferous forests is true?

Coniferous forests experience precipitation that is mainly in the form of snow.

Which of the following statements about coniferous forests is true?

Coniferous forests may experience considerable precipitation, but usually in the form of snow.

The Yellowstone to Yukon Conservation Initiative is a plan to

Connect parks in the United States and Canada with protected corridors where wildlife can travel safely

If an overlap develops between the ranges of two closely related species, and if the species occupy the same niche in the zone of overlap, what will probably happen in the zone of overlap? A) A new species will arise by hybridization. B) Both species will coexist, provided the environment in the zone of overlap is different from that in either individual range. C) Both species will coexist, provided the environment in the zone of overlap is similar to that of one of the individual ranges. D) One species will take over most or all of the zone of overlap

Skill: Application/Analysis 5) Uniform spacing patterns in plants such as the creosote bush are most often associated with A) chance. B) patterns of high humidity. C) the random distribution of seeds. D) competitive interaction between individuals of the same population. E) the concentration of nutrients within the population's range.

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) effect of grazing intensity by bison on plant species diversity

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) facilitation

28) All of the following have been used by plants to avoid being eaten except

D) producing tissues that have unappealing colors.

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) producing tissues that have unappealing colors.

50) You are most likely to observe primary succession in a terrestrial community when you visit a(n)

D) recently created volcanic island.

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) recently created volcanic island.

35) The dominant species in a community is

D) the species that contributes the most biomass to the community.

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 species that contributes the most biomass to the community.

2) The principle of competitive exclusion states that

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

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

Which statement about human population growth is true?

Demographic transition is a transition from high birth rates and high death rates to low birth rates and low death rates.

Permafrost is characteristic of the ________

Desert Tundra X Temperate forest Taiga

the immediate resuts of the widepreaduse of pesticides and fertilizers included ______, but long-term esults included _____.

Dramatic increases in crop yields... the evolution of pest resistance.

A) grows at its maximum per capita rate

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

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

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

Aquatic biomes are distinguished primarily by a) their temperatures. b) their turbidity. c) the speeds of their current. d) their pH. e) their salinity.

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

Essentially all of the other species depend on the presence of the elephants to maintain the community

Fresh water and seawater mix in a(n) _______.

Estuary

1) Which of the following statements is consistent with the principle of competitive exclusion?

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

Some populations, especially those with high genetic variability and short life spans, may avoid extinction as the climate changes through

Evolutionary adaptation

Which of the following pairs of reproductive strategies is consistent with energetic trade-off and reproductive success?

Female rabbits that suffer high predation rates may produce several litters per breeding season, and coconuts produce few fruits, but most survive when they encounter proper growing conditions.

Which example best describes both an elemental pool where an element accumulates and an elemental sink where it is removed from circulation and locked up for long periods?

Fossil fuel deposits in which carbon is stored for hundreds of millions of years

___________of the landscape can transform once-continuous populations into metapopulations.

Fragmentation

Consider the following prairie food chain. Tall grass is consumed by grasshoppers that, in turn, are eaten by mice, and the mice are eaten by prairie kingsnakes. Red-tailed hawks prey on mice and prairie kingsnakes. When a red-tailed hawk dies, bacteria, beetles, fungi, and many types of worms help break down the body. Which of the following correctly identifies a trophic level in this ecosystem?

Grasshoppers are primary consumers.

Which of the following would be considered a biotic factor in the environment of an aquatic animal?

Gut flora

Which of the following would be considered a biotic factor in the environment of an aquatic mammal?

Gut flora

Which of the following species has te highest assimilation efficiency?

Herbivorous insect

What item does not constitute a resource for a rodent?

High temperature experienced in the desert

Why is a pathogen generally more virulent in a new habitat?

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

A population is correctly defined as having which of the following characteristics? I.inhabiting the same general area II.belonging to the same species III.possessing a constant and uniform density and dispersion

I and II only

The following question refers to the figure, which depicts the age structure of three populations.Which population(s) is (are) in the process of decreasing?

Which statement about subpopulations within metapopulations is false?

If the patch habitat is favorable, extinction of a small subpopulation is highly unlikely. True: Compared to larger subpopulations, smaller subpopulations have a greater risk of going extinct due to environmental disturbances. Compared to larger subpopulations, smaller subpopulations have a greater risk of going extinct because of chance factors. Dispersal between subpopulations can increase the length of time during which a metapopulation can persist. A subpopulation that exchanges migrants is an open system.

Which statement about carrying capacity (K) is true?

In a population at its K, the birth rate equals the death rate

Which statement best describes an important distinction between the BD model and the BIDE model?

In the BD model, once the density equals zero, it remains at zero. In the BIDE model, density can go from zero to non-zero.

The dominant herbivores in savannas are ________.

Insects

The human growth curve is best described as being

J-shaped

What kind of curve represents exponential growth?

J-shaped

A regional assemblage of interacting ecosystems is a

Landscape

Which of the following statements about deserts and the organisms that live there is true?

Many desert animals are nocturnal.

Which statement about deserts and the organisms that live there is true?

Many desert animals are nocturnal.

Habitats with many edges

Often result from human activities

Sparrows eat both insects and seeds. To which trophic level do they belong?

Omnivore

Ecology is the study of environmental interactions at the following levels, from least inclusive to most inclusive:

Organism, population, community, ecosystem

Which statement regarding logistic growth is true?

Population growth is zero when (K − N)/K is equal to zero.

The pool of a substance in a compartment is 45 kilograms for one month. In the previous month, the pool was 40 kilograms. What is net flux into the compartment?

Positive 5 kilograms/month

Which of the following statements is false?

Regional stochasticity reduces the importance of refuge habitats or dormant life stages.

The flux that is responsible for transferring carbon from the land to the atmosphere is called:

Respiration

The aspect of conservation ecology concerned with returning degraded ecosystems (as nearly as possible) to their natural state is

Restoration ecology

In terms of global air circulation, the tropics are a region where air _______.

Rises and Cools, dropping rain

Global warming is the result of

Rising concentrations of greenhouse gases

A photograph of a Victorian trophy room shows the heads of 15 species of hoofed mammals, all shot within a day's walk of a single hunting camp in Africa. This camp was probably located in ________.

Savanna

Many of the world's most spectacular animals- including giraffes, zebras, lions, and cheetahs- are all found in which biome?

Savanna

The ______ is a showcase of large herbivores and their predators

Savanna

Which of the following is an example of predation?

Sea anemones coating the shallow-water coral reefs in Australia feed on fish and shrimp that wander too close to their tentacles.

Which statement regarding food webs is true?

Several species of primary consumers may feed on the same species of producer.

Which of the following statements about population dynamics in source-sink populations is true?

Sink populations may persist even if r < 0.

According to the island biogeography model, which two factors primarily determine the number of species on an island?

Size of island and distance from the mainland

Which of the following is an example of mutualism?

Some biologists have observed Egyptian plover birds land on the open mouth of a Nile crocodile without being eaten and remove leeches stuck firmly to the crocodile's gums.

Which result is an observed effect of global warming on organisms?

Some species of birds and frogs now begin their breeding seasons earlier in the year

Why is territoriality an adaptive behavior for songbirds maintaining populations at or near their carrying capacity?

Songbird males defend territories commensurate with the size from which they can derive adequate resources for themselves, their mate, and their chicks.

Development of which of the following technological advances most likely did not cause a jump in the human growth rate?

Space flight

Which of the following is an example of herbivory?

Squirrels in the forests of Wisconsin hide away hickory nuts and acorns, which they will eat during the long, cold winter.

_____ is the goal of developing, managing, and conserving Earth's resources in ways that meet the needs of people today without compromising the ability of future generations to meet theirs.

Sustainability

The ________ biome contains land that can be used for highly productive agriculture

Temperate grassland

In any food chain, the top level of consumers is quaternary (fourth). Why are there almost never any fifth-level consumers?

There is not enough available energy to sustain a fifth level.

How do human activities such as deforestation and cattle grazing affect Earth's water cycle?

They decrease precipitation and increase runoff.

Biotic factors

______ include all of the organisms in the area. They are the living component of the environment.

The current rate of extinction may be as much as ________ times higher than at any other time in the past 100,000 years. a. 1,000 b. 100 c. 10 d. 10,000

Which of the following is responsible for the summer and winter stratification of deep temperate lakes? A) Water is densest at 4°C. B) Oxygen is most abundant in deeper waters. C) Winter ice sinks in the summer. D) Stratification is caused by a thermocline. E) Stratification always follows the fall and spring turnovers.

A number of populations of different species interacting with one another in a natural environment, such as a rotten log, is called

a community

The death by bubonic plague of about one-third of Europe's population during the 14th century is a good example of

a density-dependent effect

All of the following could reasonably lead to the extinction of small subpopulations of a native plant except

a large immigration rate.

Which of the following represents a community with the greatest species richness?

a plant community with 12 different species, in which each species consists of only about 100 plants

Which of the following organisms best illustrates K-selection?

a polar bear producing one or two cubs every three years

In terms of population dynamics, "boom-and-bust" cycling is a situation in which

a population moves back and forth between rapid growth and decline.

The introduction of a large predatory fish species into a lake will lead to declines in populations of smaller fish, which in turn cause an increase in plankton. This series of events is one example of (SG q 07, 08)

a trophic cascade

GPP and NPP are most closely associated with a. community function. b. community structure. c. species composition. d. species richness. e. island biogeography.

a. community function.

A demographic tool used to predict a population's future growth is a(n)

age structure diagram

The three basic variables that make up the life history of an organism are

age when reproduction begins, how often reproduction occurs, and how many offspring are produced per reproductive episode.

Which of the following is an example of a population?

all of the redwood trees that live in a forest

Which of the following is an example of a population?

all of the students in your classroom

Photosynthetic organisms are called _____.

autotrophs

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

Phytoplankton is most frequently found in which of the following zones? A) oligotrophic B) photic C) benthic D) abyssal E) aphotic

All of these factors reduce the efficiency of energy transfer between trophic levels except

biomass stored as fat or starch

Because the environment is complex, organisms can potentially be affected by many different variables. Ecologists group these variables into two major types: ______ and ________ factors.

biotic factors abiotic factors

An area in which different terrestrial biomes grade into each other is known as a(n) A) littoral zone. B) vertically stratified canopy. C) ecotone. D) abyssal zone. E) cline.

Species found in only one place on Earth are called ________ species. a. exotic b. keystone c. endemic d. hot spot

Examine Figure 37.9 in your textbook, which shows a food web. If the snake population were suddenly reduced because of a virus that kills only snakes, we would expect that the population of _____.

cacti would suffer from increased herbivory

Which type of biome would most likely occur in a climate with mild, rainy winters and hot, dry summers?

chaparral

In which of the following terrestrial biome pairs are both parts dependent upon periodic burning?

chaparral and savanna

Probably the most important factor(s) affecting the distribution of biomes is (are)

climate.

Earth acts as a(n) _______ system in terms of materials and a(n) ________ system in terms of energy.

closed; open

In wild populations, individuals most often show a _____ pattern of dispersion.

clumped

The pattern of distribution for a certain species of kelp is clumped. The pattern of distribution for a population of snails that live on the kelp would be

clumped

The pattern of distribution for a certain species of kelp is clumped. The pattern of distribution for a population of snails that live on the kelp would be

clumped.

Interaction between two species as both attempt to use the same environmental resources is

competition

What type of population interaction benefits neither population?

competition

Similar species occupying slightly different niches in the same community is shown by

competition between two species of barnacles in Scotland resulting in one living in the intertidal zone and the other living below this species.

Which term describes the concept that no two species can have the same "job" in the community at the same time?

competitive exclusion

A Daphnia population in a pond has more resources than it needs until its population reaches 50% of its carrying capacity. At that point, the population begins to experience a food shortage. The population will

continue growing but at a lower growth rate

Species in widely separated but similar biomes often appear to display similar characteristics because of

convergent evolution

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

convergent evolution

A regional assemblage of interacting ecosystems is a a. biome. b. PVA. c. hot spot. d. landscape.

About one-third of all animal and plant species are concentrated on ________ of Earth's land. a. 10% b. 5% c. 20% d. 1.5%

According to this graph of changes in Earth's atmosphere, which of the following took place between 1800 and 2000? a. Nitrous oxide levels increased from 270 ppb to 390 ppb. b. Carbon dioxide levels increased from 950 ppb to 1,800 ppb. c. Methane levels increased from 270 ppm to almost 2,000 ppm. d. Carbon dioxide levels increased from 290 ppm to 380 ppm.

Approximately ________ living species have been named and described. a. 750,000 b. 30 million c. 10 million d. 1.8 million

Based on the characteristics of the snakehead described, which of the following is most likely to be a productive strategy to reduce the spread of this species? a. introducing a fungus that prevents fish eggs from hatching b. extending the fishing season for prey fishes c. introducing algae and photosynthetic bacteria to reduce nutrient levels in the water d. introducing a natural predator to feed on juvenile snakeheads

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

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

If Earthʹs axis of rotation suddenly became perpendicular to the plane of its orbit, the most predictable effect would be A) no more night and day. B) a big change in the length of the year. C) a cooling of the equator. D) a loss of seasonal variation at high latitudes. E) the elimination of ocean currents

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

Which of the following is not true about estuaries? A) Estuaries are often bordered by mudflats and salt marshes. B) Estuaries contain waters of varying salinity. C) Estuaries support a variety of animal life that humans consume. D) Estuaries usually contain no or few producers. E) Estuaries support many semiaquatic species.

Which of the following statements about the ocean pelagic biome is true? A) The ocean is a vast, deep storehouse that always provides sustenance; it is the next ʺfrontierʺ for feeding humanity. B) Because it is so immense, the ocean is a uniform environment. C) More photosynthesis occurs in the ocean than in any other biome. D) Pelagic ocean photosynthetic activity is disproportionately low in relation to the size of the biome. E) The most abundant animals are unicellular zooplankton.

The doubling time of a population of annual plants is 10 years. Assuming that the initial population size is 500 and that the rate of increase remains constant, how large will the population be after 30 years? a. 1,000 b. 1,500 c. 2,000 d. 4,000 e. 8,000

d. 4,000

The mammalian fauna of an island is behaving in accordance with the MacArthur and Wilson theory of island biogeography. If the food supply on the island is permanently reduced, you would expect the number of mammalian species to _______, because _______ will _______. a. increase; immigration; increase b. increase; extinction; increase c. decrease; immigration; decrease d. decrease; extinction; increase e. decrease; extinction; decrease

d. decrease; extinction; increase

In an altitudinal gradient, all of the following would change in the same way as in a latitudinal gradient except

day length.

Suppose you are in an area where Lyme disease is prevalent. There is a decrease in the size of the acorn crop. This change will most likely lead to a(n) _______ in the incidence of Lyme disease because there is a decrease in the size of _______ populations.

decrease; rodent

suppose you are in an area where Lyme disease is prevalent. there is a decrease in the size of the acorn crop. this change will most likely lead to a(n) _______ in the incidence of Lyme disease because there is a decrease in the size of _______ populations.

decrease; rodent

Which of the following will likely decrease a population's size?

decreasing the food supply available to the population

At the local or within-patch scale, population growth and regulation is determined by

demographic processes.

Which of the following choices causes all of the others in creating global terrestrial climates?

differential heating of Earth's surface

Which of the following choices includes all of the others in creating global terrestrial climates?

differential heating of Earth's surface

Gopher tortoises feed on grasses such as wire grass. The tortoise creates burrows in the ground that can also be used by other species such as burrowing owls, rabbits, and indigo snakes with no negative effect on the tortoise. The species interaction between gopher tortoises and wire grass can best be described as a ___________ relationship and an example of __________. The interaction between the tortoise and the indigo snake would best be described as a ________ relationship an and an example of ______________ . direct, commensalism; direct, herbivory direct, herbivory; indirect, commensalism direct, ammensalism; direct, mutualism direct, parasitism; indirect, commensalism

direct, herbivory; indirect, commensalism

At the regional, or metapopulation, scale, population growth and regulation is determined by

dispersal, extinction, and colonization.

which adaptation helps an organism get rid of excess water?

drip tips on leaves

The growing season would generally be shortest in which of the following biomes? A) savanna B) temperate broadleaf forest C) temperate grassland D) tropical rain forest E) coniferous forest

Which biome is able to support many large animals despite receiving moderate amounts of rainfall? A) tropical rain forest B) temperate forest C) chaparral D) taiga E) savanna

Which of the following could be a density-independent factor limiting human population growth?

earthquakes

The conditions under which an organism survives and exists in the community is called its

ecological niche

The sum total of an organism's interaction with the biotic and abiotic resources of its environment is called its

ecological niche

The study of the interrelationships of plants and animals with each other and with their environment is known as

ecology

What generally flows in one direction through an ecosystem, from producers up through each level of consumers, and is not recycled?

energy

The flow of ________ into ecosystems occurs in one direction only, while ________ are recycled within the ecosystem itself.

energy . . . chemicals

which statement best describes the interaction of energy and materials, or process of ecosystem function, within an ecosystem?

energy and materials enter biotic components through primary producers, energy flows one way and materials cycle.

In the ocean, the biomass of large predators (e.g., sharks and tuna) is much smaller than that of herbivorous animals (e.g., small fish and phytoplankton). This is because

energy transfer between trophic levels is inefficient

The flow of ________ into ecosystems occurs in one direction only, while ________ are recycled within the ecosystem itself.

energy; chemicals

The area where fresh water and seawater mix is called a(n)

estuary

according to Figure 1 from Erisman et al. 2008:

fertilizer use has increased since 1950; meat production has increased since 1950; nitrogen inputs from the Haber-Bosch process aid in sustaining a higher human population

Much of the chaparral vegetation requires ________ for increasing nutrient availability and reproduction.

fire

Factors that help to limit growth of woody plants in temperate grasslands include:

fires and grazing by large mammals

Factors that help to limit the growth of woody plants in temperate grasslands include

fires and grazing by large mammals.

match the following term to the definition

fixation: conversion of dinitrogen gas to ammonium decomposition: breakdown of organic nitrogen to dissolved organic nitrogen mineralization: conversion of dissolved organic nitrogen into ammonium denitrification: conversion of organic nitrogen to dinitrogen gas nitrification: conversion of ammonium to nitrate

an organism living on the leeward side of a mountain would most likely have which adaptation?

fleshy, water-storing leaves or stems

Which of the following is regarded as a density-independent factor in the growth of natural populations?

flooding

A survivorship curve is a

graph that plots an individual's likelihood of being alive as a function of age

A major reason why populations in larger patches have a lower extinction probability is

greater habitat heterogeneity

A broad-based pyramid-shaped age structure is characteristic of a population that is _____.

growing rapidly

While on a walk through a forest, you notice birds in trees, earthworms in the soil, and fungi on plant litter on the forest floor. Based on your observations, you conclude that each of these organisms occupies a different

habitat.

An r-selected species typically

has an advantage in habitats that experience unpredictable disturbances

The Allee effect is used to describe a population that

has become so small that it will have difficulty surviving and reproducing.

Which statement about the phosphorus cycle is false?

he main abiotic reservoir for phosphorus is in the water.

Which ecological problem might result from fertilizing a golf course with phosphorus-rich fertilizer?

heavy growth of algae and cyanobacteria in lakes and rivers caused by phosphorus runoff

A primary consumer

herbivore

Which of the following statements accurately describes the less developed countries?

high birthrate, large pre-reproductive portion of the population

Which of the following choices would most likely promote random distribution?

homogeneous chemical and physical factors in the environment

Which of the following would most likely promote random distribution?

homogeneous chemical and physical factors in the environment

Biotic potential depends on all of the following EXCEPT

how many different mates each individual has.

the study of ecology includes understanding all of the following EXCEPT

how to change environmental policy

Which of the following has the greatest impact on the global water cycle?

human destruction of forests

The difference between the BD growth model and the BIDE model is the inclusion of _______ in the BIDE model.

immigration and emigration

To best manage wildlife populations, wildlife managers must identify the life history stages that are

important in determining survival and growth rate

Parasites are found

in all kingdoms and sometimes one parasite uses more than one host to disperse.

When climbing a mountain, we can observe transitions in biological communities that are analogous to the changes

in biomes at different latitudes

which statement best describes an important distinction between the BD model and the BIDE model?

in the BD model, once the density equals zero, it remains at zero. In the BIDE model, density can go from zero to non-zero

A scientist observes a population of grasshoppers in a farmer's field several times over the summer. She notices that after each application of an insecticide the grasshopper population increases to its pre-pesticide levels very rapidly and that the population never goes near zero at any time. The scientist's results indicate the grasshopper population is probably

in the exponential growth phase.

The BIDE model of population growth differs from the BD model in that it

includes both immigration and emigration

If most of the individuals of a human population are in their pre-reproductive years, you would expect the population size to ________ after 20 years.

increase

You are a species of squirrel that is preyed upon by foxes, which are preyed upon by mountain lions. A new species of squirrel is introduced to your ecosystem. This squirrel eats entirely different plants than you do, but it shares the same fox predator. What do you predict the population of the fox will do over time, in response to this change in the biotic environment? (hint: foxes in this system are food limited). increase decrease stay the same

increase

When resources such as food and roost sites are available at normal levels but environmental temperatures drop to stressful levels, a crow would likely

increase allocation of resources to body maintenance

In Pacific kelp forests, sea otters feed on sea urchins, which in turn feed on kelp. In some areas, sea otter populations are locally extinct due to hunting. In the absence of sea otters, populations of sea urchins would be expected to _______ and populations of kelp would be expected to _______.

increase; decrease

In metapopulations, the rate of local population extinction ________ as the proportion of patches occupied increases.

increases

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

a cow ingests 100 kilojoules of energy from eating grass of which 60 kilojoules are egested. an additional 30 kilojoules of energy are lost through respiration. the assimilation of efficiency of the grass the cow ate:

is 40%; can be calculated by dividing the assimilated energy the the ingested energy

An ecological footprint

is a means of understanding resource availability and usage

which of the following is NOT true about production efficiency?

is lowest in poikilotherms

Which of the following is NOT true about production efficiency?

is lowest in poikilotherms True: decreases at higher trophic levels is the percent of assimilated energy that goes into producing new biomass can be calculated as the growth plus energy in offspring divided by the assimilated energy

To construct a life table for a sexual species, one needs to

keep track of the females in a cohort.

To construct a reproductive table for a sexual species, one needs to

keep track of the females in a cohort.

In a tide pool, 15 species of invertebrates were reduced to 8 after one species was removed. The species removed was likely a(n)

keystone species.

Ecological systems are _______ over space and time.

known to vary

Metapopulations with _________ patches that are relatively _________ each other will have the highest proportion of patches occupied.

large, close to

Based on the theory of island biogeography, we would expect _______ islands to have greater biodiversity than ______ islands.

large; small

an organism adapted to a dry climate would most likely live on the ______ side of a mountain

leeward

Hanski found that vertebrates have generally ____ variability in population size and a ___ degree of density dependence than do the invertebrate populations examined.

less, greater

as compared with low latitudes, high latitudes receive ______ energy from sunlight over the year because the sun's rays are at _____ angle

less; a more shallow

NPP in aquatic ecosystems is most often limited by

light and nutrient availability.

rooted aquatic plants would most likely be found in which zone?

littoral zone

Consider two forests: one is an undisturbed old-growth forest and the other has recently been logged. In which forest are species likely to experience exponential growth, and why?

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

A newly mated queen ant establishes an ant nest in an unoccupied patch of suitable habitat. The population of the nest grows quickly at first, then levels off at carrying capacity. Which of the following models best describes its population growth?

logistic

A population's carrying capacity

may change as environmental conditions change.

Living things that live in the polar ice biome include

mosses, lichens, seals, and polar bears

a moth and a beetle both lay eggs on the same species of plant and the larvae of both develop on the plant. removal experiments show that the moth and the beetle each perform less well on the plant when the other species is removed. the relationship between the moth and the beetle is best described as

mutalism

51) Which of the following describes the relationship between ants and acacia trees?

mutualism

A bird eats the fruit of a plant species. The seeds are not digested and germinate in the bird's excrement at some distance from the parent plant. This is an example of

mutualism

Evidence shows that some grasses benefit from being grazed. Which of the following terms would best describe this plant-herbivore interaction?

mutualism

Evidence shows that some grasses benefit from being grazed. Which of the following terms would best describe this plant-herbivore interaction?

mutualism

When two different populations in a community benefit from their relationship with each other, the result is called

mutualism

Which of the following describes the relationship between legumes and nitrogen-fixing bacteria?

mutualism

Which of the following terms best describes the interaction between termites and the protozoans that feed in their gut?

mutualism

In tropical forests, there are plants known as ant-plants. These plants host ant colonies. When the ant colony is the species Petalomyrmex phylax, the presence of the ants protects the ant-plants from predation by herbivores. However, the ant species Cataulacus mckeyi takes advantage of the nesting place and nectar the plants provide without affording any protection to the plant. The interspecies interaction between the ant-plants and P. phylax is an example of _____ whereas the interaction between the ant-plants and C. mckeyi is an example of _____.

mutualism ... parasitism

Species in a(n) _______ interaction increase each other's per capita growth rate.

mutualistic

Resource competition, territoriality, disease, and toxic wastes are some of the factors that provide _____ and help regulate population.

negative feedback

The sum total of a population's use of the biotic and abiotic resources of its habitat constitutes its

niche

According to the competitive exclusion principle, two species cannot continue to occupy the same

niche.

According to the competitive exclusion principle, two species cannot continue to occupy the same

niche.

Bacteria are especially important in making _____ available to plants.

nitrogen

Based on our knowledge of the factors influencing primary productivity, the lowest level of net primary production would most likely be found in forests located in

northern Canada.

The growing season would generally be shortest in which of the following biomes?

northern coniferous forest

Which of the following is NOT a form of environmental resistance?

number of offspring produced per litter

Commensalism is the type of interaction in which

one participant benefits and the other is unaffected

There are several species of grain beetles that can live on dry meal obtaining water mostly as metabolic water. Many of these beetle species are grain pests that do considerable damage to stored grain. You set up a dozen jars of dry meal and introduce fifty individuals of each species to each jar, being careful to have half of each species from each sex. The food supply is sufficient to last for a year and the size is adequate so that wastes do not become toxic. Most likely, examination of the jars in six months will find

only one species per jar, similar to the classic experiment with paramecia.

Except near hydrothermal vents, the communities of the oceanic aphotic zone get their energy mainly from

organic matter sinking from the photic zone.

"How do individuals survive extreme cold environments?" is a question that could be addressed by studying which scale of ecological organization?

organism

Ecology is the study of environmental interactions at the following levels, from least inclusive to most inclusive: __________

organism, population, community, ecosystem

the study of ecology is organized into different disciplines that are studied at different scales. Select the answer that correctly orders the disciplines of ecology from the smallest to largest scale

organism; population; community; ecosystem; biosphere

In ecosystems, organisms at the highest trophic levels usually contain less collective biomass than the organisms at lower trophic levels because _____.

organisms are inefficient at converting the energy they consume to biomass

Ecology is best defined as the study of

organisms as they interact with other organisms and with their physical surroundings.

an organism living in an estuarine biome would most likely be an

osmoregulator

The precipitation flux exceeds evaporation over land over the oceans over neither

over land

In addition to abiotic factors, the community composition of plants can be severely compromised by

parasites and pathogens.

parasitism

The freshwater leech is an organism that feeds off of the blood of other organisms such as frogs and turtles. Which interaction describes the relationship between freshwater leeches and frogs or turtles?

parasitism

A Type I survivorship curve is associated with which of the following life history traits?

parents providing extended care for their young

The chaparral biome is maintained by _____.

periodic fires

A group of individuals of a single species that occupy the same general area defines a

population

All the members of the same species that inhabit a particular area are termed a(n)

population

When the number of births exceeds the number of deaths, this results in

population growth.

In an ecosystem, you would expect to find interspecific competition between

populations of two species that occupy the same niche.

What is a metapopulation?

populations that are linked by immigration and emigration

The current human population per capita growth rate is

positive, but lower than it was in 1963.

When you eat an apple, you are serving as a _____.

primary consumer

Herbivores are _____.

primary consumers

In a hypothetical food chain consisting of grass, grasshoppers, sparrows, and hawks, the grasshoppers are

primary consumers.

For a given area and time period, the amount of solar energy converted to chemical energy in organic compounds is called

primary production

For a given area and time period, the amount of solar energy converted to chemical energy in organic compounds is called

primary production.

The relationship between biomass and primary productivity is that _____.

primary productivity is the rate at which biomass is produced

Within an ecosystem, a tree is a

producer.

Our current ability to feed the people of the world would improve if people ate a diet that only consisted of _____.

producers

which statement are TRUE about the Haber-Bosch process?

provides a source of synthetic fertilizer that can be used for crops; synthesizes ammonia by reacting N2 with hydrogen in the presence of iron at high pressure and temperature; produces more ammonium annually than what is fixed by biological organisms; provides the raw materials for explosives

A population age structure in which the birthrate is high and the population is mainly young would be best represented by a graph with a(n)

pyramid shape.

In terrestrial systems, the two major climatic factors affecting the distribution of organisms are __________.

rainfall and temperature

In ocean environments, the highest net primary productivity tends to be in coastal zones and upwelling zones, because they receive the most rainfall. receive constant inputs of nutrients. are all in temperate or tropical zones. are shallow and therefore receive the most sunlight. are close to hydrothermal vents, which provide nutrients.

receive constant inputs of nutrients.

Which of the following groups would be most likely to exhibit uniform dispersion?

red squirrels, who actively defend territories

which change is most likely to increase r?

reproduction switching to younger individuals

The _________ describes situations where the risk of local extinction decreases because of high rates of immigration from a large population

rescue effect

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 toward the top, whereas the white-breasted nuthatch searches from the top of the trunk down. These hunting behaviors best illustrate which of the following ecological concepts?

resource partitioning

what is the fundamental distinction between resources and physical conditions?

resources can be used up, but conditions cannot

the flux that is responsible for transferring carbon from the land to the atmosphere is called

respiration

Global warming is the result of

rising concentrations of greenhouse gases.

to reduce the incidence of Lyme disease, the most important factor is to control the population size of _______, because this in turn reduces the number of larval ticks that _______.

rodents; find blood meals

Many of the world's most spectacular animals — including giraffes, zebras, lions, and cheetahs — are all found in which biome

savanna

Which biome is able to support many large animals despite receiving moderate amounts of rainfall?

savanna

Tropical grasslands with scattered trees are also known as

savannas.

what is a direct consequence of the 23-degree tilt of Earth's axis?

seasonality

community establishment immediately following the eruption of Mt. St. Helen can be best described as

secondary succession

When a New England farm is abandoned, its formerly plowed fields first become weedy meadows, then shrubby areas, and finally forest. This sequence of plant communities is an example of

secondary succession.

Female rabbits that suffer high predation rates may produce several litters per breeding season, and coconuts produce few fruits, but most survive when they encounter proper growing conditions.

semelparous reproduction.

The shortgrass prairie is found in relatively _______ regions, while tallgrass prairie forms in _______ areas.

shortgrass prairie = dry regionstall grass prairie = wetter areas

Many marine phytoplankton construct shells from calcium carbonate (CaCO3). In the carbon cycle, the shells

sink to ocean sediments when the organisms die, and form limestone, locking up the carbon.

If an ecosystem has a carrying capacity of 1,000 individuals for a given species and 2,000 individuals of that species are present, we can predict that the population

size will decrease

Which of the following graphs illustrates the population growth curve of single bacterium growing in a flask of ideal medium at optimum temperature over a 24-hour period?

slow positive curve

In a natural metapopulation of lizards having various subpopulations, a subpopulation that is _______ is most likely to result in the extinction of that individual subpopulation.

small with no immigration

Which of the following is an abiotic reservoir?

soil

Which of the following is a physical factor that can limit the geographic distribution of species?

soil structure

Temperate grassland is characterized by _________ made rich in nutrients by glacial deposits, and ______ from decaying plant material.

soils,mulch

Which of the following factors would have the LEAST impact on a deep-sea hydrothermal vent community?

solar energy

Species richness and relative abundance define the _____ of a community.

species diversity

The relative abundance of any one species within a community of many species is known as

species evenness.

The number of species in a community is called the

species richness.

In a patchy habitat, a group of smaller, isolated _______ form a single large _______.

subpopulations; metapopulation

The _______ spatial unit represents a collection of metapopulations that have diverged from other groups of metapopulations.

subspecies

You decide to follow the development of the human gut microbiota over time by isolating the bacteria expelled in the solid waste of infants from birth to 24 weeks old. Your lab can process the poop of three infants a week, so you study three babies. All three infants display the same data. You find that the population of bacteria in the gut is dominated by one species for the first four weeks of an infant's life, and then three species dominate for the next six weeks. Then two of those species are replaced by four new species. Reference: Diaper ecology The data suggests the gut bacterial community is undergoing

succession because a predictable turnover in species is occurring, transitioning the barren newborn gut into a healthy microbiome.

What is the ultimate source of energy for nearly all surface terrestrial and shallow water ecosystems?

sunlight

The main reason that polar regions are cooler than the equator is that

sunlight strikes polar regions at a lower angle.

In which community would organisms most likely have adaptations enabling them to respond to different photoperiods?

temperate forest

In which of the following biomes would you expect to find the highest abundance of large, grazing mammals?

temperate grassland

Most of the best agricultural soils in the United States are found in areas that were formerly

temperate grasslands

Which of the following abiotic factors has the greatest influence on the metabolic rates of plants and animals?

temperature

Important abiotic factors in ecosystems include which of the following?

temperature water wind

The kind of terrestrial biome that exists in a particular region depends largely on __________ and __________

temperature; precipitation

In an average ecosystem, about how much energy is present in the organisms at a given trophic level compared to the organisms at the next higher trophic level?

ten times as much

Which of the following is the best example of uniform distribution?

territorial songbirds in a mature forest during mating season

In a food chain consisting of phytoplankton → zooplankton → fish → humans, the humans are

tertiary

For conservation purposes, a continuous corridor of habitat would be least needed for a species

that can fly.

A BIDE model of population growth is more applicable than a BD model for a population

that is part of a metapopulation.

During the spring, you are studying the mice that live in a field near your home. The population density is high, but you realize that you rarely observe any reproductive female mice. This most likely indicates

that you are observing immigrant mice.

Which variables define the ecological life history of a species?

the age at which reproduction begins, frequency of reproduction, and the number of offspring for each reproductive episode

The main cause of the increase in the amount of carbon dioxide in Earth's atmosphere over the past 150 years is

the burning of larger amounts of wood and fossil fuels

Biodiversity considers

the genetic diversity within and between populations of a species.

All parts of the biosphere are linked by

the global water cycle and nutrient cycles.

Which could be a topic for a community-level study of a hydrothermal vent ecosystem?

the interactions between crabs and other species near hydrothermal vents

The carrying capacity of the environment for a species is determined by

the limited productivity of the environment and the environmental resistance to the biotic potential of the organism.

Carrying capacity is

the maximum population size that a particular environment can support.

The observation that members of a population are uniformly distributed suggests that

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

the following are reasons why plant growth is limited by nitrogen even though nitrogen is in large supply in the atmosphere EXCEPT

the nitrogen in the soil gets leached away to the groundwater

researchers manipulated moss patches to test whether sub-populations are more likely to persist if there are no barriers to dispersal. which statement is NOT true about their study?

the number of arthropod species was greater in the patches connected to the corridor than the number on the mainland

In models of logistic population growth,

the population growth rate slows dramatically as N approaches K.

Age structure diagrams with a broad base suggest that

the population will continue to grow for some time.

What is the age structure of a population?

the proportion of individuals alive in different age-groups

Which of the following does not impact an organism's biotic potential?

the rate of immigration into an area

Defensive strategies are most likely to evolve in

the resource of a consumer-resource relationship

The demographic transition, where population growth slows in developed countries, may be attributed at least in part to

the rise of medicine.

Farmers sprayed leechi trees to suppress populations of scale insects. This also killed the populations of a predatory lacewing that controlled the numbers of scales. Soon the spraying did no good, and the damage to the leechi from the scales was greater than before spraying had occurred. Few predatory lacewings existed in the trees now because

the scale insect was an opportunistic species and the high number of young included a resistant strain; the predator was an equilibrium species and will take longer to produce a resistant variety.

Ecology

the scientific study of the interactions between organisms and the environment.

To determine the density of a rabbit population, you would need to know the number of rabbits and _____.

the size of the area in which they live

Examine the age structure of Germany in the figure below. Which of the following statements is not supported by the age structure?

there will be a large positive population growth in the near future

how do human activities such as deforestation and cattle grazing affect Earth's water cycle?

they decrease precipitation and increase runoff

If secondary consumers are the highest trophic level in a community, how many trophic levels does that community have (not counting decomposers)? Two Three Four Three if it is an aquatic community, four if it is a terrestrial community Three if it is a terrestrial community, four if it is an aquatic community

three

Conservation of critical parts of food webs is important because removal of these critical species may

trigger trophic cascades

When wolves were eliminated from Yellowstone National Park in 1926, elk populations ballooned, followed by changes in populations of aspen trees, streamside willows, and beavers. This removal of a single species resulted in a series of ecosystem changes known as a

trophic cascade

Which trophic level in this food chain represents the secondary consumer?

trophic level C

The feeding relationship between species in a community is called

trophic structure.

Which of the following biomes is correctly paired with the description of its climate?

tropical forests-nearly constant day length and temperature

The greatest annual input and least seasonal variation in solar radiation occurs in the

tropics

results from Simberloff and Wilson's study in 1969 investigating arthropod recolonization after fumigation in islands that vary in distance to the mainland support the Theory of Island Biogeography.

true

smaller fragments have a greater proportion of their area influenced by edge effects than larger fragments

true

Which of the following options correctly pairs a biome and its characteristics?

tundra=very cold winters; only the upper layer of the soil thaws during summer

Consider the life of the praying mantis. The large predatory female lays several hundred eggs in a foam mass in the fall. The young are most vulnerable when they emerge in the spring, but the few that survive spread out over the countryside and, if they find a mate, lay eggs the following fall. Which type of survivorship curve does this represent?

type III

You drive through Iowa in the spring and notice that along a stretch of several kilometers, every third fence post has a male redwing blackbird perched on it defending its nesting territory. This is an example of

uniform dispersion

which statement about air temperature is true?

warm air is lighter than cold air, and thus will rise

Two competing species usually can coexist when interspecific competition is _______ intraspecific competition weaker than stronger than equal to

weaker than

If an ecologist wants to study a system with the least ecological complexity, she should examine one

with an individual organism interacting with two other organisms of the same species in an isolated community.

Approximately how many kg of carnivore production can be supported by a field plot containing 2000 kg of plant material?

Assume that a population of marmots fits the BD model, with no movement into or out of the population. If 245 individuals are in the population at the start of the month, 43 die during the month, and 37 are born during the month, what is the population size of the marmots at the end of the month?

239

assume that a population of marmots fits the BD model, with no movement into or out of the population. if 245 individuals are in the population at the start of the month, 43 die during the month, and 37 are born during the month, what is the population size of the marmots at the end of the month?

239

The pool of a phosphorus compartment is 645 units. Two fluxes enter the pool: one is 13 units per day; the other is 34 units per day. Two fluxes leave: one is 22 units per day; the other rate is unknown. If the pool of phosphorus is balanced, the size of the second outgoing flux is _______ units per day.

At the beginning of May, 259 butterflies are found in a certain locality. During the month, 45 butterflies emigrate, 10 die, and 67 immigrate into the area. There are no butterfly births. What is the population size at the end of the month?

271

at the beginning of May, 259 butterflies are found in a certain locality. during the month, 45 butterflies emigrate, 10 die, and 67 immigrate into the area. there are no butterfly births. what is the population size at the end of the month?

271

based on the information given, how many hectares do you predict the star-thistle population will cover in 1, 2, and 3 more years if the population is growing additively by a constant number?

3, 4, and 5 hectares

ice cores can be used to reconstruct past climates as far back as

400,000 years

44) According to the Shannon Diversity Index, which block would show the greatest diversity?

Examine Figure 41.2. According to the Shannon diversity index, which block shows the greatest diversity?

In the figure above, which number would designate the artic tundra biome?

With a few exceptions, most of the food chains studied by ecologists have a maximum of how many links

In an ecosystem, GPP was measured as 75 units of carbon per year and NPP was measured as 25 units per year. How many units of carbon per year was used for respiration?

in an ecosystem, GPP was measured as 75 units of carbon per year and NPP was measured as 25 units per year. how many units of carbon per year was used for respiration?

In an ecosystem where 500,000 kcal of sunlight is available for producers, approximately how much chemical energy will be contained in secondary consumers?

50 kcal

Grain is eaten by cows, and cows are eaten by humans. If the ecological transfer efficiency between each trophic level is 10 percent, how much grain is required to produce 70 kg of human biomass? 7 kg 70 kg 700 kg 7,000 kg 70,000 kg

7,000 kg

If humans eat the grain directly instead of eating the cows, how much grain is required to produce 70 kg of human biomass (assuming ecological transfer efficiency is 10%)? 7 kg 70 kg 700 kg 7,000 kg 70,000 kg

700 kg

Eighty-one pocket gophers were present in Maddox Field at the start of 2006. During that year, 24 individuals were born and 19 died. Twelve individuals immigrated and 10 emigrated. How many pocket gophers were present in Maddox Field at the start of 2007?

eighty-one pocket gophers were present in Maddox Field at the start of 2006. During that year, 24 individuals were born and 19 died. twelve individuals immigrated and 10 emigrated. how many pocket gophers were present in Maddox Field at the start of 2007?

Suppose the population density of a sample of a bagworm population is 45 per square meter. Assuming that the population is uniformly distributed, what would be the population size if the bagworms encompassed an area that was 1 km × 200 m?

9 million

If gross primary productivity (GPP) is 120 units per day, and the respiration rate (R) of primary producers is 30 units per day, net primary productivity (NPP) is _______ units per day. [Note: Use the formula NPP = GPP - R.]

46) An ecological footprint is a construct that is useful A) for a person living in a developed nation to consider to make better choices when using global food and energy resources. B) for a person living in a developing country to see how much of the world's resources are left for him/her. C) in converting human foods' meat biomass to plant biomass. D) in making predictions about the global carrying capacity of humans. E) in determining which nations produce the least amount of carbon dioxide from the burning of fossil fuels.

68) Your friend comes to you with a problem. It seems his shrimp boats aren't catching nearly as much shrimp as they used to. He can't understand why because he used to catch all the shrimp he could handle. Each year he added a new boat, and for a long time each boat caught tons of shrimp. As he added more boats, there came a time when each boat caught somewhat fewer shrimp, and now, each boat is catching a lot less shrimp. Which of the following topics might help your friend understand the source of his problem? A) density-dependent population regulation and intrinsic characteristics of population growth B) exponential growth curves and unlimited environmental resources C) density-independent population regulation and chance occurrence D) pollution effects of a natural environment and learned shrimp behavior E) a K-selected population switching to an r-selected population

A hypothetical grassland community has the following five trophic levels: (1) grasses and other plants; (2) herbivores, such as aphids, rodents, and antelope; (3) carnivores, such as ladybugs and weasels, that feed mainly on herbivores; (4) carnivores, such as wolves and hawks, that feed on level (3) carnivores as well as on herbivores; and (5) detritivores, such as vultures, fungi, and bacteria. If a drought occurred, which of the consumer levels would most likely be affected first? (Assume that adequate drinking water remains available.) A) 2 B) 3 C) 4 D) 5 E) 3 and 4

In a hypothetical food chain consisting of grass, grasshoppers, sparrows, and hawks, the grasshoppers are A) primary consumers. B) primary producers. C) secondary consumers. D) secondary producers. E) detritivores.

Select all of the following that accurately explain why populations grow more slowly as they approach their carrying capacity. a) Density-dependent factors lead to fewer births and increased mortality. b) Hormonal changes promote higher death rates in crowded populations. c) Individuals voluntarily stop mating so that overcrowding does not occur. d) The incoming energy decreases in populations experiencing a high rate of increase. e) Density-independent factors lead to fewer births and increased mortality.

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

We expect that a keystone species that is a predator will A) maintain the species diversity in a community. B) harvest prey species down to extinction. C) help many of its prey reproduce. D) be a parasite. E) More than one of the choices is correct

When potassium is in high supply, two species of algae have higher growth rates in the presence of each other than they do alone. When potassium is in short supply, species A still performs better in the presence of species B, but species B is not affected by the presence of species A. The increase in potassium thus changes a relationship of _______ to one of _______. A. commensalism; mutualism B. commensalism; consumer-resource C. amensalism; mutualism D. amensalism; commensalism E. commensalism; amensalism

Which of the following is false? Natural selection A) results from an organism's needs. B) and evolutionary change can occur in a short time. C) depends on the time and place. D) can be seen working on organism alive today.

Which one of the following statements is false? A) Small-scale disturbances rarely have positive effects. B) Storms, fire, freezing, glacial advance and retreat, and volcanic eruptions are types of disturbances. C) Primary succession occurs when a community arises in a virtually lifeless area with no soil. D) Secondary succession occurs where a disturbance has destroyed an existing community but left the soil intact. E) The transition in species composition in a community is called ecological succession.

You want to do all that you can to safeguard the environment by preserving energy. One simple thing that you can do is to eat a diet consisting only of organisms that are A) producers. B) primary consumers. C) secondary consumers. D) a mix of producers and consumers.

In the nineteenth century, a few dozen European starlings were deliberately introduced to New York City's Central Park in an effort to reconstruct familiar surroundings from Western Europe. The descendants of the initial introduction now number in the millions, and have spread widely across North America. The starlings found in North America today are thus _______. a) invasive b) native c) accidental d) non-invasive non-natives e) None of the answers are correct

A The introduced European starlings are invasive because they have dramatically increased in numbers and spread widely. The introduction was deliberate

Which of the following is a correct statement about The MacArthur/Wilson Island Equilibrium Model is a bad model because the name tells us very little about the model. Nevertheless, it is important. From the choices below, select all the FALSE statements about The MacArthur/Wilson Island Equilibrium Model. a) As the number of species on an island increases, the emigration rate decreases. b) Typically, as island size increases the number of plant species increases. c) Islands closer to the mainland have higher extinction rates. d) Competitive exclusion is less likely on an island that has large numbers of species. e) Small islands receive few new immigrant species. f) The more species that inhabit an island, the lower the extinction rate.

A C D F

Select all the examples of aposematic coloration. a) the brightly colored patterns of poison dart frogs b) a katydid whose wings look like a dead leaf c) colors of an insect-pollinated flower d) larva of the monarch butterfly which are very visible and poisonous e) eye color in humans f) green color of a plant

A D

Which of these research topics would be considered an example of community ecology?

A researcher found that the reproductive success of bumblebees decreased when the population density of honeybees increased. The decline in the number of bumblebees appeared to be a result of competition for nectar.

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) Essentially all of the other species depend on the presence of the elephants to maintain the community.

56) A community's actual evapotranspiration is a reflection of

A) solar radiation, temperature, and water availability.

A community's actual evapotranspiration is a reflection of 10 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) solar radiation, temperature, and water availability.

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) stripes of a skunk

12) Which of the following is an example of Müllerian mimicry?

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

A young hen is removed from a relatively uncrowded cage and placed in a small space with many other hens. Although the amount of resources she receives in the new environment is unchanged, the crowding is stressful. Given this circumstance, this hen will most likely spend more resources on

A. maintaining proper balance of electrolytes and other chemicals.

two species of beetles have partially overlapping distributions, with the range of species A extending farther north and the range of species B extending farther south. the distribution of species B is limited mainly by cold temperatures, while that of species A is limited mainly by competition from species B. given these parameters, the distribution of species _________ would most likely move farther ________ if the other species went extinct.

A; south

Which of the following best describes the consequences of white-band disease in Caribbean coral reefs?

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

Which statement about the human intestine is false?

All of the above are true; none is false It can act as an ecosystem for bacteria. It is densely populated with bacteria. It receives a steady supply of nutrients. Its environment is regulated within narrow physiological limits.

Permafrost, bitterly cold temperatures, and high winds are responsible for the absence of trees and tall plants in the ________ tundra.

Arctic tundra

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

3) An owl and a hawk both eat mice. Which of the following describes the relationship between a hawk and an owl? A) predation B) competition C) mutualism D) parasitism

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

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

4) When two different populations in a community benefit from their relationship with each other, the result is called A) herbivory. B) mutualism. C) parasitism. D) competition.

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

43) A population of white-footed mice becomes severely overpopulated in a habitat that has been disturbed by human activity. Sometimes intrinsic factors cause the population to increase in mortality and lower reproduction rates to occur in reaction to the stress of overpopulation. Which of the following is an example of intrinsic population control? A) Owl populations frequent the area more often because of increased hunting success. B) Females undergo hormonal changes that delay sexual maturation and many individuals suffer depressed immune systems and die due to the stress of overpopulation. C) Clumped dispersion of the population leads to increased spread of disease and parasites, resulting in a population crash. D) All of the resources (food and shelter) are used up by overpopulation and much of the population dies of exposure and/or starvation. E) Because the individuals are vulnerable they are more likely to die off if a drought or flood were to occur.

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

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

A biology teacher takes fish, algae, pond weed, invertebrates, and bottom muck from a local pond and establishes them in an aquarium. When the system is stable, the teacher seals it into a large, airtight glass box and leaves the box in a sunny location. After 3 months, the organisms in the aquarium appear alive and healthy. Which of the following statements about the experiment is false? A) No energy has entered or left the glass box during the 3 months. B) Some of the energy in the system has moved from one organism to another during the 3 months. C) Some atoms from water molecules have become parts of organic molecules. D) The air in the glass box contains carbon dioxide. E) During the 3 months, the biomass of plant life was greater than the biomass of animal life

A hypothetical community on a barren mid-Atlantic island consists of two fish-eating seabirds (the booby and the noddy), fungi and microorganisms that live on the birds' dung, a tick that feeds on these two birds, a cactus, a moth that feeds on cast-off feathers, a beetle that lives on dung organisms, and spiders that eat the other arthropods. There are no plants and no lichens. Which of the following choices incorrectly pairs a member of this assemblage with its position in the trophic structure? A) spiders, secondary consumer B) booby and noddy birds, primary consumers C) fungi, detritivores D) moths, detritivores E) the cactus is a producer

A trophic level consists of the organisms a) that use similar foraging methods to obtain food. b) whose energy has passed through the same number of steps to reach them. c) that compete with one another for food. d) that are eaten by a similar set of predators. e) that eat both plants and other animals.

According to Malthus, the food supply for humans increases _______, but the population grows _______. A. logistically; multiplicatively B. additively; multiplicatively C. logistically; additively D. multiplicatively; logistically E. multiplicatively; additively

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

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

Approximately how many kilograms of secondary consumer biomass can be supported by a field plot containing 1,000 kg of plant material? a) 10,000 b) 10 c) 1,000 d) 100 e) 1

Corridors help mitigate the effect of habitat fragmentation because they a) increase ecological efficiency. b) increase the probability of migration between patches. c) increase NPP. d) lower the likelihood of interspecific competition. e) enhance the quality of habitat.

Denitrifying bacteria convert ________ to ________. A) ammonium . . . nitrates B) nitrates . . . nitrogen gas C) nitrogen gas . . . nitrates D) nitrogen gas . . . nitrites

Managing southeastern forests specifically for the red-cockaded woodpecker a) involved the creation of fragmented forest habitat b) included providing nesting cavities for breeding groups c) required the growth of a dense understory of trees and shrubs d) involved strict fire-suppression measures e) caused other species of songbird to decline

Skill: Knowledge/Comprehension 12) Which of the following scenarios would provide the most legitimate data on population density? A) Count the number of nests of a particular species of songbird and multiply this by a factor that extrapolates these data to actual animals. B) Count the number of pine trees in several randomly selected 0 m x 0 m plots and extrapolate this number to the fraction of the study area these plots represent. C) Use the mark-and-recapture method to estimate the size of the population. D) Calculate the difference between all of the immigrants and emigrants to see if the population is growing or shrinking. E) Add the number of births and subtract the individuals that die to see if the population's density is increasing or decreasing.

The NPP of the Marquette Campus Ecosystem is most likely a __________ and the NEP of the Marquette Campus Ecosystem is most likely a ____________. a) positive number; positive number b) positive number; negative number c) negative number; positive number d) negative number; negative number e) Not enough information to answer this question.

The global hydrologic cycle begins with precipitation falling to earth, and the cycle is completed by _______. A) photosynthesis B) transpiration C) degradation D) Both A and B are correct E) Both A and C are correct

The number of species in a community is called the A) species diversity. B) species richness. C) species population. D) species index.

The primary decomposers of a community are called A) primary consumers. B) detritivores. C) primary producers. D) protozoa. E) herbivores.

The recovery of willows and aspens after their reintroduction into Yellowstone National Park demonstrated the phenomenon of A. succession. B. trophic cascades. C. ecological efficiency. D. transect analysis. E. None of the above

Two days ago, Jimmy the monarch caterpillar ate a milkweed leaf. Jimmy got himself eaten by a goldfinch today. Bummer for Jimmy. What happened to the chemical energy contained in the milkweed leaf that Jimmy ate that was not converted to new biomass in Jimmy's body? a) It is only used by organisms to maintain their life processes through the reactions of cellular respiration. b) It is eliminated as feces or is dissipated into space as heat in accordance with the second law of thermodynamics. c) All of it is undigested and winds up in the feces and was not passed on to the goldfinch. d) Heat produced by cellular respiration is used by heterotrophs to thermoregulate. e) It is recycled by decomposers to a form that is once again usable by primary producers.

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

Which of the following is not true of the nitrogen cycle? A) It requires different types of bacteria. B) Nitrogen gas is converted to nitrates in plant leaves. C) Nitrogen is cycled through living organisms. D) When plants and animals die, their nitrogen is recycled. E) Nitrogen is a component of all proteins.

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

Which of the following participants would receive an increase in its population growth rate from a given interspecific interaction? A. A resource in a consumer-resource interaction B. A consumer in a consumer-resource interaction C. A competitor in a competition interaction D. Both a and b E. None of the above

Which of the following statements about climates is true? a) On average, regions near the equator receive substantially more hours of sun each year than do regions near the 45° latitudes. b) The rate at which solar energy arrives on any surface depends on the angle of the sunlight. c) There is no difference between "weather" and "climate." d) Air temperature usually increases with increasing elevation. e) None of the answers are correct.

Which of the following statements about the phosphorus cycle is true? A) Phosphorus has its main abiotic reservoir in water. B) Plants release dissolved phosphorus ions in the soil. C) Phosphorus that drains from soils into the sea becomes part of new rock and will cycle back into living organisms. D) Guano can be used by farmers to add phosphorus to the soil.

Your evil roommate has a ecological location destroying device. If targeted by this evil decide, which location, if destroyed, would result in the greatest loss of species diversity? a) islands b) tropical rain forest c) grasslands d) deciduous forests e) tundra

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

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

B) character displacement.

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 it

B) ecological niche.

In a tide pool, 15 species of invertebrates were reduced to eight after one species was removed. The species removed was likely a(n)

B) keystone species.

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 species.

Which of the following describes the relationship between ants and acacia trees? A) parasitism B) mutualism C) inhibition D) facilitation E) commensalism

B) mutualism

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) mutualism

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) niche.

29) The species richness of a community refers to the

B) number of different species.

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) number of different species.

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 4 B) parasitism C) commensalism D) facilitation E) competition

B) parasitism

3) Keystone predators can maintain species diversity in a community if they

B) prey on the community's dominant species.

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) prey on the community's dominant species.

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?

B) resource partitioning

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 5 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) resource partitioning

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) sympatric populations of species with similar ecological niches.

) The most plausible hypothesis to explain why species richness is higher in tropical than in temperate regions is that

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

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

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

Which of the following members of a marine food chain occupies a similar tropic level to a grasshopper in a terrestrial food chain?

B) zooplankton

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) zooplankton

The harmless orange-and-black viceroy butterfly closely resembling the toxic orange-and-black monarch butterfly is an example of

Batesian mimicry

Rising concentrations of carbon dioxide (CO2) in the atmosphere result in the oceans

Becoming more acidic

Which of the following terms include all of the others?

Biodiversity

Small areas that are home to a large number of threatened species and an exceptional concentration of species found nowhere else on Earth are called

Biodiversity hot spots

You spray your lawn with a pesticide. The concentration of the pesticide in the tissues of the grass on your lawn is 10−6 parts per million (ppm). Grasshoppers eat the grass and are in turn eaten by rats, which are then eaten by owls. At each successive trophic level, the concentration of pesticides increases. The term for this process is

Biological magnification

Using living organisms to clean up polluted ecosystems is known as

Bioremediation

All of earth is inhabited by life is called the.

Biosphere

2) One reason it is important to understand community ecology is A) to understand the life cycle of fish, such as cichlids. B) for identification of stomach microbes. C) to aid in conservation of endangered species. D) to provide an enriched habitat for humans.

20) Which of the following statements regarding food webs is true? A) A consumer eats only one type of producer. B) Detritivores consume dead organic matter from a specific trophic level. C) Several species of primary consumers may feed on the same species of producer. D) energy transfer moves from producer to consumer and back.

22) In your backyard you overturn a large rock. In the damp soil underneath the rock, you see various insects scurrying for cover: one black spider, five black ants, two brown beetles, and three gray pillbugs. In this community of organisms, species richness is represented by A) the ants, since there are more of them than any other organism. B) eleven total organisms. C) four different species of organisms. D) the ants and the spider equally, since they have the greatest number of organisms of the same color.

23) In 2008, the population of New Zealand was approximately 4,275,000 people. If the birth rate was 4 births for every 1,000 people, approximately how many births occurred in New Zealand in 2008? A) 6,000 B) 42,275 C) 60,000 D) 140,000 E) 600,000

24) Consider two forests: one is an undisturbed old-growth forest, while the other has recently been logged. In which forest are species likely to experience exponential growth, and why? A) Old growth, because of stable conditions that would favor exponential growth of all species in the forest. B) Old growth, because each of the species is well established and can produce many offspring. C) Logged, because the disturbed forest affords more resources for increased specific populations to grow. D) Logged, because the various populations are stimulated to a higher reproductive potential. E) Exponential growth is equally probable in old-growth and logged forests.

24) When a New England farm is abandoned, its formerly plowed fields first become weedy meadows, then shrubby areas, and finally forest. This sequence of plant communities is an example of A) evolution. B) a trophic chain. C) secondary succession. D) primary succession.

27) For a given area and time period, the amount of solar energy converted to chemical energy in organic compounds is called A) primary succession. B) secondary succession. C) primary production. D) secondary production.

30) Which trophic level in this food chain represents the secondary consumer? A) trophic level A B) trophic level B C) trophic level C D) trophic level D

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

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

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

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

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

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

A population is A) a collection of communities. B) a group of individuals of different species living in the same place at the same time. C) the smallest unit that can evolve. D) applicable only to animals that reproduce asexually. E) All of the choices are correct.

A porcupine eats 3,000 J of plant material. Of this, 2,100 J are indigestible and are eliminated as feces, 800 J are used in cellular respiration, and 100 J are used for growth and reproduction. What is the approximate production efficiency of this animal? a) 27% b) 33% c) 3% d) 0.03% e) 11%

Climate has many effects on biome distribution across the planet. Select the statement from the options that describes the major effects of climate on biome distribution? a) Correlation of climate with biome distribution is sufficient to determine the cause of biome patterns. b) Average annual temperature and precipitation are sufficient to predict which biome will be found in an area. c) Not only is the average climate important in determining biome distribution but so is the pattern of climatic variation. d) Seasonal fluctuation of temperature is not a limiting factor in biome distribution if areas have the same annual temperature and precipitation means. e) Temperate forests and grasslands are different biomes because they receive a different quality and quantity of sunlight, even though they have essentially the same annual temperature and precipitation.

During primary succession, select the organisms that are most likely to be the first photosynthetic colonizer? a) shrubs b) flowering plants c) lichens d) trees e) grasses

Eighty-one pocket gophers were present in Maddox Field at the start of 2006. During that year, 24 individuals were born, and 19 died. Twelve individuals immigrated, and 10 emigrated. How many pocket gophers were present in Maddox Field at the start of 2007? a) 81 b) 86 c) 88 d) 146 e) 76

For a given area and time period, the amount of solar energy converted to chemical energy is called A) primary succession. B) secondary succession. C) primary production. D) secondary production. E) primary photosynthesis.

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

Non-native species that are introduced in new environments, spread far beyond the original point of introduction, and cause damage are called A) destructive species. B) enemy species. C) invasive species. D) proprietary species.

One of the most worrisome results of the large-scale clearing and cultivation of land is A) erosion and soil degradation. B) the inability to supply fresh water. C) the inability fo supply enough food for growing populations. D) hurricanes.

One reason it is important to understand community ecology is A) to understand the life cycle of fish, such as cichlids. B) for identification of stomach microbes. C) to aid in conservation of endangered species. D) to provide an enriched habitat for humans.

Over the summer you get a summer intern with a fancy-pants ecologist. All summer you record the number of white-tailed deer, Odocoileus virginianus, in two different locations. You record 12 white-tailed deer, Odocoileus virginianus, per square mile in one woodlot and 20 per square mile in another woodlot. What comparision does your data allow you to make? a) Odocoileus virginianus carrying capacity b) Odocoileus virginianus range c) Odocoileus virginianus density d) Odocoileus virginianus dispersion e) Odocoileus virginianus cohorts

Owls are really awesome. Typically, owls eat rats, mice, shrews, and small birds. Assume that, over a period of time, an owl consumes 5,000 J of animal material. The owl loses 2,300 J in waste (feces and owl pellets) and uses 2,600 J for cellular respiration. What is the production efficiency of this owl? a) 0.02% b) 1% c) 4% d) 10% e) 40%

Skill: Application/Analysis 10) Long-term studies of Belding's ground squirrels show that immigrants move nearly 2 km from where they are born and become %-8% of the males and 0.7%-6% of the females in other populations. On an evolutionary scale, why is this significant? A) These immigrants make up for the deaths of individuals, keeping the other populations' size stable. B) Young reproductive males tend to stay in their home population and are not driven out by other territorial males. C) These immigrants provide a source of genetic diversity for the other populations. D) Those individuals that emigrate to these new populations are looking for less crowded conditions with more resources. E) Gradually, the populations of ground squirrels will move from a clumped to a uniform population pattern of dispersion.

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

The biosphere A. includes land and water, but not the atmosphere. B. is thick relative to Earth's radius. C. is where life exists on Earth. D. includes biotic but not abiotic components. E. None of the above

Two species of beetles are both herbivores on the same host plant, and the presence of either beetle species reduces the population growth of the other. The relationship between these beetles is best described as a) amensalism. b) herbivory. c) competition. d) predation. e) commensalism.

Unfortunately, conservation biologists have to make determinations on which degraded ecosystems to attempt to restore. Which of the following is the most important consideration when it comes to managing ecosystems for maintenance of biodiversity? a) maintaining optimum size of all populations in the ecosystem b) identifying large, high-profile vertebrates first, because steps to saving them would be most recognized by the public c) determining which species is most important for conserving biodiversity as a whole d) altering habitat to be more suitable for a rare bird species

When a crocodile eats a fish, the interspecific interaction between the two could be expressed as ________ for the crocodile and ________ for the fish. A) . . . B) + . . . + C) + . . . D) . . . +

Which of the following can potentially influence effective population size (Ne)? a) body size of individuals b) length of life span after reproduction c) amount of gene flow between geographically separated populations d) number of alleles per trait

Which of the following frequently cycles through the environment, bypassing biotic components and relying completely on geological processes? A) carbon B) nitrogen C) water D) nitrogen and carbon E) carbon and nitrogen

Which of the following is not an example of a rarity advantage? A. A nematode is more likely to parasitize a species of Drosophila when the fly density is high. B. Robins have more difficulty catching earthworms when there are few worms. C. One species of beetles eats leaves in a canopy, while a related species eats leaves that are closer to the ground. D. Each of two competing species of snapdragons has a higher birth rate and lower death rate when it is less common than the other species. E. All of the above are examples of a rarity advantage.

Which of the following represents a step in the nitrogen cycle? A) nitrogen-fixing bacteria convert atmospheric nitrogen to nitrates B) nitrites bind to soil particles C) nitrogen-fixing bacteria convert atmospheric nitrogen to ammonium D) denitrifiers convert ammonium to atmospheric nitrogen

Which of the following will result in an increase of species richness? a) A decrease in evapotranspiration. b) Diving underwater. c) Traveling southward from the North Pole to the equator. d) Communities that experience frequent disturbance events. e) Moving from islands close to the mainland to islands far from the mainland.

The food web has _______ trophic levels. a) six b) three c) four d) two e) five

C Four trophic levels are depicted. The levels are primary producer (1), herbivore (also called primary consumer: 2, 3, 4), primary carnivore (also called secondary consumer: 5, 6), and secondary carnivore (also called tertiary consumer: 7, 8). The omnivore (9) occupies either the herbivore or primary carnivore level, depending on whether it is feeding on a primary producer or on an herbivore.

What is the mathematical representation of the rate of colonization in a metapopulation (C)?

C = [mP(1 − P)]

Select all the choices that are accurate differences between an endangered species and a threatened species. a) only endangered species are vertebrates b) a threatened species is closer to extinction c) an endangered species is closer to extinction d) both species have an increased likelihood of going extinct e) endangered species are mainly tropical

C D

Select all of the terrestrial biome that are dependent upon periodic burning. a) temperate broadleaf forest b) desert c) savanna d) tundra e) chaparral f) tropical

C E

Select all the examples of Batesian mimicry. a) a fawn with fur coloring that camouflages it in the forest environment b) a butterfly that resembles a leaf c) a nonvenomous snake that looks like a venomous snake d) a snapping turtle that uses its tongue to mimic a worm, thus attracting fish e) the larva of the hawkmoth

C E

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) 5

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

C) Batesian mimicry.

13) Which of the following is an example of Batesian mimicry?

C) a non-venomous snake that looks like a venomous snake

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) a non-venomous snake that looks like a venomous snake

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) commensalism: as one increases the other stays the same

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?

C) facilitate

5) Based on the intermediate disturbance hypothesis, a community's species diversity is

C) increased by moderate levels of disturbance.

According to the equilibrium model of island biogeography, species richness would be greatest on an island that is

C) large and close to a mainland.

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

C) moderate levels of disturbance.

4) Food chains are sometimes short because

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

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

Given that CO2 is produced by cellular respiration, why does the amount of CO2 in the atmosphere remain relatively constant? (When answering this question, exclude the impact of human activities on atmospheric CO2.)

CO2 is converted in photosynthesis to carbohydrates.

Protecting the endangered black-footed ferret from extinction involved

Captive breeding and reintroduction

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

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.

The relationship between a zebra and the lion that eats it is an example of what kind of interaction?

Consumer-resource

Which process does not occur in ecosystems?

Consumers directly use the energy source that powers the system.

A semiarid Texas ecosystem is dominated by a mixture of shortgrass prairies and chaparral. Primary producers include grasses and other herbaceous flowering plants (forbs). Chaparral has shrubs, including mesquite and yucca, intermixed with grasses and forbs. Herbivores include jackrabbits and cottontails. They are eaten by badgers, bobcats, skunks, and gray fox. The top-level predator is the coyote. Which level of this ecosystem contains the least energy?

Coyotes

15) Within an ecosystem, a tree is a A) secondary consumer. B) detritivore. C) primary consumer. D) producer

22) In July 2008, the United States had a population of approximately 302,000,000 people. How many Americans were there in July 2009, if the estimated 2008 growth rate was 0.88%? A) 2,700,000 B) 5,500,000 C) 303,000,000 D) 304,000,000 E) 2,70,800,000

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

25) The flow of ________ into ecosystems occurs in one direction only, while ________ are recycled within the ecosystem itself. A) minerals; energy compounds B) genetic information; genotypes C) organic compounds; minerals D) energy; chemicals

26) Which of the following processes does not occur in ecosystems? A) Energy flows through the system. B) Carbon is cycled between biotic and abiotic forms. C) Producers convert light energy to chemical energy. D) The energy source that powers the system is used by consumers to make organic compounds.

28) In an average ecosystem, about how much energy is present in the organisms at a given trophic level compared to the organisms at the next higher trophic level? A) a tenth as much B) half as much C) twice as much D) ten times as much

39) Often the growth cycle of one population has an effect on the cycle of another. As moose populations increase, for example, wolf populations also increase. Thus, if we are considering the logistic equation for the wolf population, dN/dt = rN (K-N)/K which of the factors accounts for the effect on the moose population? A) r B) N C) rN D) K E) dt

67) To measure the population of lake trout in a 250-hectare lake, 400 individual trout were netted and marked with a fin clip, then returned to the lake. The next week, the lake was netted again, and out of the 200 lake trout that were caught, 50 had fin clips. Using the capture-recapture estimate, the lake trout population size could be closest to which of the following? A) 160 B) 200 C) 400 D) 1,600 E) 80,000

69) Imagine that you are managing a large game ranch. You know from historical accounts that a species of deer used to live there, but they have been extirpated. You decide to reintroduce them. After doing some research to determine what might be an appropriately sized founding population, you do so. You then watch the population increase for several generations, and graph the number of individuals (vertical axis) against the number of generations (horizontal axis). The graph will likely appear as A) a diagonal line, getting higher with each generation. B) an "S," increasing with each generation. C) an upside-down "U." D) a "J," increasing with each generation. E) an "S" that ends with a vertical line.

7) The freshwater leech is an organism that feeds off of the blood of other organisms such as frogs and turtles. Which of the following describes the relationship between freshwater leeches and frogs or turtles? A) herbivory B) predation C) mutualism D) parasitism

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

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

8) The sum total of a population's use of the biotic and abiotic resources of its habitat constitutes its A) environment. B) evolution. C) range. D) niche.

A beetle that was introduced to Hawaii some time ago, has rapidly increased in number, and now causes damage to native vegetation would be considered a) endemic. b) commensal. c) amensal. d) invasive. e) evasive.

All of the following are threats to biodiversity, which is the most direct threat to biodiversity? a) increased levels of atmospheric carbon dioxide b) the depletion of the ozone layer c) zoned reserves d) habitat destruction e) overexploitation of selected species

During ecological succession, the species composition of a plant community generally A) changes from a diverse community in which many plants are common to one in which a few species are numerically dominant. B) simplifies until most of the plants originally present have disappeared. C) remains stable as long as major environmental factors (climate, human interference) remain constant. D) changes gradually because each species responds differently to the changing environment. E) changes until climax forest is established and a single species remains.

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 and can be harmed if nutrients and water are scarce in the environment. Which of the following best describes the interactions between dwarf mistletoes and trees? a) commensalism b) facilitation c) competition d) parasitism e) mutualism

If an overlap develops between the ranges of two closely related species, and if both species occupy the same niche in the zone of overlap, what will probably happen in the zone of overlap? A) The two species will interbreed and produce a hybrid species. B) Both species will coexist, provided the environment in the zone of overlap is different from that in either individual range. C) The species will divide up the zone so that half of it is added to the range of the species and there is no overlap. D) One species will exclude the other from most or all of the zone of overlap. E) Both species will coexist, provided the environment in the zone of overlap is similar to that of one of the individual ranges.

If the total amount of energy from light converted into chemical energy in this square meter of tundra is 200 g, what is the amount of autotrophic respiration? a) 85 g b) 0.5 g c) 200 g d) 100 g e) 15 g

In an average ecosystem, about how much energy is present in the organisms at a given trophic level compared to the organisms at the next higher trophic level? A) a tenth as much B) half as much C) twice as much D) ten times as much E) It is impossible to say without knowing which trophic levels are involved.

Overharvesting encourages extinction of many different types of animals. From the list below, select the type of animal that is most likely affected by overharvesting. a) animals that occupy a broad ecological niche b) edge-adapted species c) terrestrial organisms more than aquatic organisms d) large animals with low intrinsic reproductive rates e) most organisms that live in the oceans

Pathogens are generally more virulent in a new habitat. Which of the following best explains this observation? a) Pathogens evolve more efficient forms of reproduction in new environments. b) More pathogens tend to immigrate into newer habitats. c) Intermediate host species are more motile and transport pathogens to new areas. d) Hosts in new environments have not had a chance to become resistant to the pathogen through natural selection. e) New environments are almost always smaller in area, so that transmission of pathogens is easily accomplished between hosts.

Skill: Application/Analysis 4) During the spring, you are studying the mice that live in a field near your home. The population density is high, but you realize that you rarely observe any reproductive female mice. This most likely indicates A) that there is selective predation on female mice. B) that female mice die before reproducing. C) that this habitat is a good place for mice to reproduce. D) that you are observing immigrant mice. E) that the breeding season is over.

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

The flow of ________ into ecosystems occurs in one direction only, while ________ are recycled within the ecosystem itself. A) minerals . . . energy compounds B) genetic information . . . genotypes C) organic compounds . . . minerals D) energy . . . chemicals

The introduction of the brown tree snake In the 1940s the brown tree snake was introduced to the island of Guam. Which of the following is a consequence of this? a) its failure to compete with native species and its quick elimination from the island b) a new species of hybrids from crossbreeding with a native snake species c) a good example of biological control d) the extirpation of many of the island's bird and reptile species e) eradication of non-native rats and other undesirable/pest species

The maximum reproductive potential of a species is its A) inalienable right. B) dominant trait. C) carrying capacity D) biotic potential

The relationship between cattle and the birds that eat insects stirred up by grazing cattle is an example of A) predation. B) parasitism. C) mutualism. D) commensalism. E) interspecific competition.

There are 150 golden shiners living in a pond. Which of the following would you need to know to calculate their population density? A. Their birth rate B. Their growth rate C. Their death rate D. The volume of water in which they live E. All of the above

When a New England farm is abandoned, its formerly plowed fields first become weedy meadows, then shrubby areas, and finally forest. This sequence of plant communities is an example of A) evolution. B) a phylogenetic trend. C) a trophic chain. D) secondary succession. E) genetic drift.

When two species are competitors, rarity advantage is likely to lead to a) the extinction of one of the species. b) an evolution of the competitive interaction into a mutualism. c) an evolution of the competitive interaction into a resource-host interaction. d) coexistence of both species. e) None of the answers are correct

Which of the following statements about the theory of island biogeography is false? a) It can be tested in natural communities. b) For communities in which species numbers are above the equilibrium, it predicts that extinction rates will be above the immigration rate. c) For communities in which species numbers are below the equilibrium, it predicts that immigration rates will be above the extinction rate. d) It is particularly concerned with the identity of species found on particular islands. e) All of the above are true; none is false.

Which one of the following is false? A) sign stimulus triggers a fixed action pattern B) Innate behaviors are often crucial to the survival of a species. C) Innate behaviors are under strong genetic control. D) Fixed action patterns are learned behavior sequences.

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) 20

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

6) Which of the following could qualify as a top-down control on a grassland community?

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

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

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

A community ecologist would most likely study A. interactions among individuals of the same species living in a small area. B. the cycling of matter through biotic and abiotic components of a geographical area. C. population growth of a single species. D. energy flow through an ecosystem. E. interactions among individuals of different species living in a small area.

According to the International Union for Conservation of Nature and Natural Resources (IUCN), 73% of species have become extinct, endangered, vulnerable, or rare because of a) overexploitation of certain species b) global climate change resulting from a variety of human activities c) stratospheric ozone depletion d) chemical pollution of water and air e) alteration or destruction of the physical habitat

According to the theory of island biogeography, if the immigration rate is equal to the extinction rate, the species richness is a) low. b) increasing. c) high. d) decreasing. e) at equilibrium.

From the choices below, select the answer that best defines a cohort. a) the number of individuals that annually die or emigrate out of a population b) a group of individuals that inhabits a small isolated region within the range for the species c) all of the individuals that are annually added to a population by birth and immigration d) the reproductive males and females within the population e) a group of individuals from the same age group, from birth until they are all dead

If an overlap develops between the ranges of two closely related species, and if the species occupy the same niche in the zone of overlap, what will probably happen in the zone of overlap? A) A new species will arise by hybridization. B) Both species will coexist, provided the environment in the zone of overlap is different from that in either individual range. C) Both species will coexist, provided the environment in the zone of overlap is similar to that of one of the individual ranges. D) The species will partition the zone so that half of it is added to the range of each species and there is no overlap. E) One species will take over most or all of the zone of overlap.

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

In Japan, seaweed and seagrass bed reconstruction includes constructing suitable seafloor habitat, transplanting seaweeds and seagrasses from natural beds using artificial substrates, and hand seeding. Which of the following correctly classifies the techniques by the major restoration strategies? a) bioremediation-transplanting seaweeds and seagrasses, hand seeding b) bioremediation-constructing seafloor habitat and using artificial substrates c) biological augmentation-hand seeding and constructing seafloor habitat d) Hippies at Grateful Dead shows-Baby hippies, Hippies at Phish shows e) biological augmentation-transplanting seaweeds and seagrasses, hand seeding

Several species of grasses benefit from being grazed by herbivores. See, plants ARE weird. This plant-herbivore interaction can best be described as? a) predation b) sadism c) commensalism d) parasitism e) mutualism f) competition

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

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

Skill: Knowledge/Comprehension 8) Which of the following examples would most accurately measure the density of the population being studied? A) counting the number of prairie dog burrows per hectare B) counting the number of times a kilometer transect is intersected by tracks of red squirrels after a snowfall C) counting the number of coyote droppings per hectare D) multiplying the number of moss plants counted in 0 quadrats of m2 each by 00 to determine the density per kilometer2. E) counting the number of zebras from airplane census observations.

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

The feeding relationships among the species of a community is the community's A) niche. B) diversity. C) density. D) richness. E) trophic structure.

What interactions exist between a lion pride and a hyena pack if they utilize the same food sources? a) -/0 b) +/- c) 0/0 d) -/+ e) -/- f) +/+ g) 0/- h) 0/+ i) +/0

What is the goal of restoration ecology? a) to manage competition between species in human-altered ecosystems b) to completely restore a disturbed ecosystem to its former undisturbed state c) to prevent further degradation by protecting an area with park status d) to replace a ruined ecosystem with a more suitable ecosystem for that area e) to speed up the restoration of a degraded ecosystem

Which curve best describes survivorship in marine molluscs?

Which of the following conditions is the most likely indicator of a population in an extinction vortex? a) The population is geographically divided into many populations. b) The population is connected only by corridors. c) The species in question is found only in small, stable pockets of its former range. d) The effective population size of the species falls below 500. e) Genetic measurements indicate a loss of genetic variation over time.

Which of the following is a possible outcome of competition involving two species? A. Reduced growth and reproductive rates for some individuals of both species B. Exclusion of one species from a habitat it would occupy in the absence of competition from the other species C. Restriction of the geographic range of one species because of competition from the other species D. Evolution of both species, allowing them to divide up the limiting resource and continue to coexist in the same locality E. All of the above

Which of the following substances is not cycled between organic matter and abiotic reservoirs? A) water B) carbon C) nitrogen D) phosphorus E) All of the choices are cycled between biotic and abiotic reservoirs

11) Which of the following is an example of cryptic coloration?

E) a "walking stick" insect that resembles a twig

Which of the following is an example of cryptic coloration? 3 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) a "walking stick" insect that resembles a twig

48) According to the nonequilibrium model,

E) communities are constantly changing after being influenced by disturbances.

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) communities are constantly changing after being influenced by disturbances.

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) ecological niche.

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

E) trophic structure.

the second law of thermodynamics states that in every energy exchange, some energy is lost as heat; that is, it becomes unavailable for further use. which of the following makes it possible for life to continue on Earth?

Earth is an open system and is continually receiving new energy

Which statement describes how climate might change if Earth was 75% land and 25% water?

Earth's daytime temperatures would be higher and nighttime temperatures lower.

The introduction of wolves into Yellowstone National Park in 1991 resulted in

Ecological changes involving numerous plant and animal species

The level of ecologic organization that incorporates abotic factors is the _____.

Ecosystem

The questions of how chemicals flow and energy cycles between organisms and their surroundings are addressed in the study of which level of ecological organization?

Ecosystem

While on a walk through a forest, you notic birds in trees, earthworms in th soil, and fungi on plnt litter on the forest foor. based on your observations, ou conclude that each of these organisms occupies a different

Habitat

Currently, the single greatest threat to biodiversity is

Habitat destruction due to humans

The three greatest current threats to biodiversity, in order starting with the greatest, are

Habitat loss, invasive species, and overharvesting

Why do moderate levels of disturbance result in an increase in community diversity?

Habitats are opened up for less competitive species.

Usually, a river ________ at its source compared to farther downstream.

Has less phytoplankton

Pronghorn antelopes are well adapted for dry conditions with extremes of temperature, especially cold. As global climate change causes the region where the pronghorns live to change, in temperature as well as plant, predator, and prey diversity and abundance, what is likely to happen to the pronghorns?

If the pronghorn population includes a genetic variation that allows survival and reproduction in the new conditions, they will adapt.

If the pronghorn population includes genetic variation that allows survival and reproduction in the new conditions, they will adapt

D) a "J," increasing with each generation

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

The climax pattern model states that the same area will always lead to a specific type of community if it is given a sufficient amount of time. Which of the following statements is true of this model?

In recent time this has been modified to recognize that while the area may return to the same biome it may not have exactly the same species diversity.

C) arrow C

In the figure above, which of the arrows represents the carrying capacity? A) arrow A B) arrow B C) arrow C D) Carrying capacity cannot be found in the figure because species under density-dependent control never reach carrying capacity.

A) curve A

In the figure above, which of the following survivorship curves most applies to humans living in developed countries? A) curve A B) curve B C) curve C D) curve A or curve B

A) line A

In the figure above, which of the lines represents the highest per-capita rate increase (r)? A) line A B) line B C) line C D) line D

Which of the following describes a type II survivorship curve (drawn by plotting the number of individuals in a given population alive at the beginning of each age interval)?

Individuals die at a constant rate throughout time.

Which statement about ecological interactions is false?

Intraspecific competition has no effect on carrying capacity. True: Interspecific competition can lead to evolution. In mutualisms, each species acts in its own self-interest. Resource partitioning can lead to the coexistence of two competing species. Intraspecific competition can lead to evolution.

) Which of the following is the most accepted hypothesis as to why invasive species take over communities into which they have been introduced?

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

Which of the following is a likely explanation for why invasive species take over communities into which they have been introduced?

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 best describes the base of a pyramid of production?

It contains the energy captured by photosynthesis.

What is one application of the metapopulation concept?

It provides a framework for species conservation when those species live in a network of habitat fragments and reserves.

If a population has a birth rate of 40 individuals per 1,000 per year and a death rate of 30 individuals per 1,000 per year, how will the population change each year? (Assume that the population is below carrying capacity and that there is no immigration or emigration.)

It will increase by 1%.

Under the conditions known as El Niño, the inorganic nutrient content of the seawater off the coast of Peru declines to very low levels. What effect will this likely have on marine life in the area?

It will reduce the abundance of phytoplankton and, consequently, the abundance of other organisms.

Lizards and guinea pigs both eat the exact same type of kibble. If you're farming for meat, and you want to maximize the production of your farm, which animal is a better choice? (note for the geeky among you: They are also the same size and same surface area : volume ratio) Lizards Guinea pigs

Lizards

Consider two forests: one is an undisturbed old -growth forest, while the other has recently been logged. In which forest are species likely to experience exponential growth, and why?

Logged, because the disturbed forest affords more resources for increased specific populations to grow.

Consider two forests: one is an undisturbed old-growth forest, while the other has recently been logged. In which forest are species likely to experience exponential growth, and why?

Logged, because the disturbed forest affords more resources for increased specific populations to grow.

Which of the following investigations would shed the most light on the distribution of organisms in temperate regions that are faced with climate change?

Look back at the changes that occurred since the Ice Age and how species redistributed as glaciers melted, then make predictions on future distribution in species based on past trends.

Which of the following describes a type III survivorship curve (drawn by plotting the number of individuals in a given population alive at the beginning of each age interval)?

Many individuals die early in life.

Why do some invertebrates, such as lobsters, show a "stair-step" survivorship curve?

Many invertebrates molt in order to grow, and they are vulnerable to predation during their "soft shell" stage.

Which of the following statements best describes the interaction between fire and ecosystems?

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

Which of the following describes a type I survivorship curve (drawn by plotting the number of individuals in a given population alive at the beginning of each age interval)?

Most individuals die of old age.

Which statement about movement corridors is true?

Movement corridors can connect otherwise isolated habitat patches

Which statement about movement corridors is true?

Movement corridors can connect otherwise isolated habitat patches.

In general, given sufficient precipitation, what relationship does NPP show to latitude?

NPP is highest at low (equatorial) latitudes and decreases at high latitudes.

The African country of Nigeria had a 4.55% population growth rate from 2005 to 2010, the highest in the world. Which statement is consistent with this fact?

Nigeria's age structure likely looks like a pyramid with a broad base.

Which process represents a step in the nitrogen cycle?

Nitrogen-fixing bacteria convert atmospheric nitrogen to ammonia.

Which of the following statements best describes the effect of climate on biome distribution?

Not only is the average climate important in determining biome distribution but so is the pattern of climatic variation.

Which of the following statements about temperate broadleaf forests is true?

Oak, hickory, birch, beech, and maple are common trees in temperate broadleaf forests.

Which statement about temperate broadleaf forests is true?

Oak, hickory, birch, beech, and maple are common trees in temperate broadleaf forests.

How might an ecologist test whether a species is occupying its complete fundamental niche or only a portion of it?

Observe whether the species expands its range after the removal of a competitor.

You are managing a metapopulation of a threatened beetle that lives on a plant that is found in patches. Because of the distribution of its host plant, the beetle is also found in patches, and these patches vary in size. If you are faced with limited resources and cannot attempt to save all of the beetle subpopulations, where should you concentrate your efforts, and why?

On the largest patches, because these have the highest potential to reseed the other patches

On the largest patches, because these have the highest potential to reseed the other patches.

If an overlap develops between the ranges of two closely related species, and if the species occupy the same niche in the zone of overlap, what will probably happen in the zone of overlap?

One species will take over most or all of the zone of overlap.

An organism living in the climate depicted in the below Walter Climate diagram would most likely have the following adaptation(s) EXCEPT:

Outer body covering highly permeable to water True: CAM photosynthetic pathway Concentrated urine Ectothermic

Which statement is NOT true about parasitism?

Parasites are always severe and usually kill a host.

The major cause of tropical deforestation is:

People clearing forests to open up land for agriculture

The chaparral biome is maintained by ________.

Periodic fires

________ is permanently frozen subsoil

Permafrost

Rank the following carbon reservoirs from smallest to largest: Soils Ocean Plant Biomass Atmosphere Fossil Fuels

Plant Biomass < Atmosphere < Soils < Ocean < Fossil Fuels

Why is the climate drier on the leeward side of mountain ranges that are subjected to prevailing winds?

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

The kind of vegetation in a tropical rain forest is generally determined by the amount of

Rainfall

Guppies from Trinidad form two distinct populations that differ in several life history traits. These traits appear to relate to the local predator populations, pike-cichlids or killifish. Which experiments would best test the heritability of these traits?

Raise both populations without predators to see if they maintain their life history traits.

Palm trees and subtropical plants are commonplace in Land's End, England, whose latitude is the equivalent of Labrador in coastal Canada, where the local flora is subarctic. Which statement best explains why this apparent anomaly exists between North America and Europe?

Regions such as Labrador are actually colder than England because colder Arctic water flows down to eastern North America and warm water from the equator flows to England.

Sustainable development will

Require global, multinational cooperation

A species of mouse mainly eats grasses. Individuals of this species are smaller in locations where it co-occurs with a second, larger rodent species that also eats grass than in locations without that larger rodent. What is the most likely cause of this difference? A trophic cascade An evolutionary arms race A mutualism evolving into a consumer-resource relationship A consumer-resource relationship evolving into a mutualism Resource partitioning

Resource partitioning

Some of the energy in the system has moved from one organism to another during the three months.

In a huge (hypothetical) experiment, scientists found that if they watered and fertilized land at 30 degrees north for 50 years, species richness increased dramatically. This observation is consistent with which hypothesis about the latitudinal gradient in species richness? Evolutionary rate hypothesis History hypothesis Species-energy hypothesis Geographic area hypothesis This observation is not consistent with any of these hypotheses.

Species-energy hypothesis

Which event is a life-history trade-off?

Strains of Drosophila melanogaster that reproduce early do not live very long.

Which of the following events might you predict to occur if the tilt of Earth's axis relative to its plane of orbit was increased to 33 1/2 degrees?

Summers and winters in the United States would likely become warmer and colder, respectively.

in many dense forests, plants living near the ground level engage in intense competition for ______.

Sunlight

Some North American glasslands are called shortgrass prairies, whereas others are called tallgrass prairies. What is the main cause of this difference in grass size?

The amount of rainfall

A fish swimming in an estuary from a river would have which of the following as its greatest physiological challenge?

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

A fish swimming into an estuary from a river would have which of the following as its greatest physiological challenge?

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

What would be the effect on climate in the temperature latitudes if Earth were to slow its rate of rotation from a 24-hour period of rotation to a 48-hour period of rotation?

The climate would stay the same. The only change would be longer days and nights.

It has been suggested that humans should "eat lower on the food chain." That is, they should eat a vegetarian or nearly vegetarian diet rather than an omnivorous diet with substantial quantities of meat. If this occurred, what would be the likely result?

The ecosystem could provide food for many more humans

Which of the following processes does not occur in ecosystems?

The energy source that powers the system is used by consumers to make organic compounds.

Which of the following statements about tropical forests is true?

The forest structure consists of distinct layers that provide many different habitats.

Biodiversity considers

The genetic diversity within and between populations of a species

As N approaches K for a certain population, which of the following is predicted by the logistic equation?

The growth rate will approach zero.

In a pine forest few other species of plants grow under the pines because the needles of pine trees are acidic and make the soil more acidic. This is an example of

The inhibition model

Which statement about the phosphorus cycle is false?

The main abiotic reservoir for phosphorus is in the water. True: Plants release dissolved phosphate ions into the soil. Phosphates that drain from soils into the sea become part of the new rock and will cycle back into living organisms.

Which statement about the nitrogen cycle is true?

The nitrogen cycle requires different types of bacteria.

As N approaches K for a certain population, which of the following is predicted by the logistic equation?

The population growth rate will approach zero.

According to Ilkka Hanski, which of the following statements about necessary conditions for a metapopulation is false?

The populations must be linked by annual migrations

Which of the following statements about bush cricket metapopulations is false?

The probability of extinction is not related to isolation

Why is the runoff from fertilized agricultural fields, even if free of pesticides, often harmful to the ecosystems of temperate lakes?

The runoff causes heavy growth of algae, which eventually die and decompose, causing oxygen depletion.

Which of the following statements about the assumptions of the simple Levins model is false?

The simple Levins model of metapopulations assumes that the probability of extinction in patches is dependent on extinction probability of other patches.

One model proposed for succession predicts that different types of plants can all colonize an area at the same time and it is chance alone that determines which one arrives first and begins the process of succession. This model is called

The tolerance model

Researchers in the Netherlands studied the effects of parental care given in European kestrels over five years. The researchers transferred chicks among nests to produce reduced broods (three or four chicks), normal broods (five or six chicks), and enlarged broods (seven or eight chicks). They then measured the percentage of male and female parent birds that survived the following winter. (Both males and females provide care for chicks.)The figure: Brood size manipulations in the kestrel: Effects on offspring and parent survival.Which of the following is a conclusion that can be drawn from this graph?

There appears to be a negative correlation between brood enlargements and parental survival.

How do human activities such as deforestation and cattle grazing affect Earth's water cycle? They speed up the water cycle. They slow down the water cycle. They increase precipitation and decrease runoff. They decrease precipitation and increase runoff. They do not affect it.

They decrease precipitation and increase runoff.

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

John Muir said, "When we try to pick out anything by itself, we find it hitched to everything else in the Universe." Which process comes most closely to the idea expressed in Muir's statement? (SG q 07)

Trophic cascades

Most biodiversity hot spots are found in ________ regions.

Tropical

Why do tropical communities tend to have greater species diversity than temperate or polar communities?

Tropical communities are generally older than temperate and polar communities.

Which statement about tropical forests is true?

Tropical forest structure consists of distinct layers that provide many different habitats

The greatest annual input and least seasonal variation in solar radiation occurs in the _____.

Tropics

Which is NOT a parasitic relationship?

Unsightly dandelions sprout in a yard and compete with the fescue grass for sunlight.

Palm trees and subtropical plants are commonplace in Land's End, England, whose latitude is the equivalent of Labrador in coastal Canada where the local flora is subarctic. Which statement best explains why this apparent anomaly exists between North America and Europe?

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

Which of the following is responsible for the summer and winter stratification of lakes?

Water is densest at 4°C.

Which of the following statements about metapopulations is false?

When moving between patches, individuals cross areas of suitable breeding and feeding habitat.

D) I, II, and III

Which of the following assumptions have to 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) competition for resources

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

Which of the following graphs best illustrates the growth curve of a small population of rodents that has increased to a static carrying capacity?

A) red squirrels, who actively defend territories

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

B) III

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

B) immigration

Why does the 2009 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

Which of the following environmental factors usually has the greatest direct effect on an organism's rate of water loss by evaporation?

Wind

In nature animals tend to be either an opportunistic or equilibrium species or somewhere along an intermediate point between the two. Why aren't there animals in nature that are both big, fierce and highly reproductive so they leave many offspring?

You can "spend" your energy to be a large equilibrium species, to produce many offspring as an opportunistic species, or to be somewhere in between, but you can't spend the energy to be both large and highly reproductive.

Abiotic factors

______ are the environment's nonliving component, the physical and chemical factors such as temperature, forms of energy available, water, and nutrients.

As climate changes because of global warming, speciesʹ 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 seeds that are easily dispersed by wind or animals. B) have thin seed coats. C) produce well-provisioned seeds. D) have seeds that become viable only after a forest fire. E) disperse many seeds in close proximity to the parent tree.

Biodiversity considers a. the genetic diversity within and between populations of a species. b. the relationships of individuals to a food chain. c. commensal relationships between species. d. the fate of water in the ecosystem.

Coral animals A) are a diverse group of cnidarians often forming mutualistic symbiotic relationships with dinoflagellate algae. B) are predominantly photosynthetic, multicellular algae. C) can tolerate low oxygen and nutrient levels, and varying levels of salinity. D) can only survive in tropical waters 30oC and above. E) build coral reefs by glueing sand particles together.

DDT and mercury a. accumulate in the tissues of organisms. b. were once used as an energy source. c. deplete the ozone layer. d. contribute to acid precipitation.

Deserts typically occur in a band at 30 degrees north and south latitude because A) descending air masses tend to be cool and dry. B) trade winds have a little moisture. C) water is heavier than air and is not carried far over land. D) ascending air tends to be moist. E) these locations get the most intense solar radiation of any location on Earth

Generalized global air circulation and precipitation patterns are caused by A) rising, warm, moist air masses cool and release precipitation as they rise and then at high altitude, cool and sink back to the surface as dry air masses after moving north or south of the tropics. B) air masses that are dried and heated over continental areas that rise, cool aloft, and descend over oceanic areas followed by a return flow of moist air from ocean to land delivering high amounts of precipitation to coastal areas. C) polar, cool, moist high pressure air masses from the poles that move along the surface, releasing precipitation along the way to the equator where they are heated and dried. D) the revolution of the Earth around the sun. E) Mountain ranges that deflect air masses containing variable amounts of moisture.

If a meteor impact or volcanic eruption injected a lot of dust into the atmosphere and reduced the sunlight reaching Earthʹs surface by 70% for one year, all of the following marine communities most likely would be greatly affected except A) deep-sea vent communities. B) coral reef communities. C) benthic communities. D) pelagic communities. E) estuary communities.

If wolves were now removed from Yellowstone National Park, we would expect that a. elk populations would increase. b. vegetation would increase, providing shelter for smaller animals. c. the vegetation would remain unchanged. d. deer populations would decrease.

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

In the development of terrestrial biomes, which factor is most dependent on all the others? A) the species of colonizing animals B) prevailing temperature C) prevailing rainfall D) mineral nutrient availability E) soil structure

One result of Costa Rica's commitment to conservation is that a. ecotourism generates many jobs and brings in a significant fraction of the country's revenue. b. about 95% of the country's land is protected in some way. c. both protected park areas and the buffer zones around them have suffered only negligible deforestation. d. destructive practices such as massive logging and large scale single-crop agriculture have been nearly eliminated.

Suppose the number of bird species is determined mainly by the number of vertical strata found in the environment. If so, in which of the following biomes would you find the greatest number of bird species? A) tropical rain forest B) savanna C) desert D) temperate broadleaf forest E) temperate grassland

The Kissimmee River Project is an a. attempt to restore the natural wetlands associated with the Kissimmee River. b. example of large-scale bioremediation to clean up a mercury spill. c. example of a dam that interrupted the breeding of salmon and other species. d. effort to join two previously unconnected lakes to permit better drainage.

The ability to change phenotype in response to local environmental conditions is called a. phenotypic plasticity. b. genetic drift. c. alteration of generations. d. mutation.

The aspect of conservation ecology concerned with returning degraded ecosystems (as nearly as possible) to their natural state is a. restoration ecology. b. landscape ecology. c. bioremediation. d. sustainable development.

The benthic zone in an aquatic biome A) often supports communities of organisms that feed largely on detritus. B) supports communities of highly motile animals. C) is where one would most expect to find a thermocline. D) has wider seasonal fluctuations in temperature than other aquatic zones. E) is always devoid of light.

To decrease pollution from sulfur, your local power plant built very tall smokestacks. The ultimate consequence of this would most likely be a. to create an environmental problem at a distance from the power plant. b. a decrease in the pH of local lakes. c. biological magnification. d. to dilute the sulfur pollutants in the atmosphere and thus reduce their effects on the environment.

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

When snakeheads enter aquatic ecosystems, biodiversity in these ecosystems would most likely a. decrease, since the snakehead will prey on native species. b. increase, since another species has been added to the environment. c. remain the same, because the snakeheads will merge without problems into established communities. d. remain the same, since local species will prey on the snakeheads and remove them.

Which of the following events might you predict to occur if the tilt of Earthʹs axis relative to its plane of orbit was increased 33.5 degrees? A) Summers and winters in the United States would likely become warmer and colder, respectively. B) Winters and summers in Australia would likely become less distinct seasons. C) Seasonal variation at the equator might decrease. D) Both northern and southern hemispheres would experience summer and winter at the same time. E) Both poles would experience massive ice melts

Which of the following statements about light in aquatic environments is correct? A) Water selectively reflects and absorbs certain wavelengths of light. B) Photosynthetic organisms that live in deep water probably use red light. C) Longer wavelengths penetrate to greater depths. D) Light penetration seldom limits the distribution of photosynthetic species. E) Most photosynthetic organisms avoid the surface where the light is not too intense.

Which of the following statements about movement corridors is true? a. Movement corridors can connect otherwise isolated habitat patches. b. Movement corridors are detrimental to species that migrate between habitats seasonally. c. Movement corridors can promote inbreeding in declining populations. d. Movement corridors can prevent the spread of disease.

Which of the following statements best describes the difference in approach to studying the environment by early naturalists compared to present-day ecologists? A) Early naturalists employed a descriptive approach; present-day ecologists generate hypotheses, design experiments, and draw conclusions from their observations. B) Early naturalists manipulated the environment and observed changes in plant and animal populations, while modern ecology focuses on population dynamics. C) Early naturalists systematically recorded what they observed in their environment; modern ecology is only concerned with manʹs impact on the environment. D) Early naturalists were interested with manʹs interaction with the natural world; present-day ecologists seek to link ecology to developmental biology. E) Early naturalists were interested in interactions between organisms and their environment; present day ecologists are interested in interactions between organisms

You are planning a dive in a lake, and are eager to observe not many underwater organisms but be able to observe them both close up and far away. You would do well to choose A) an oligotrophic lake. B) an eutrophic lake. C) a relatively shallow lake. D) a nutrient-rich lake. E) a lake with consistently warm temperatures.

Which of the following describes a Type II survivorship curve?

a constant death rate over the organism's life span

Which of the following is most clearly a case of density-dependent population regulation?

a dangerous new flu strain that is transmitted among humans by sneezing

Which of the following best defines a cohort?

a group of the individuals from the same age group, from birth until they are all dead

A change in population growth from a J-shaped curve to an S-shaped curve represents a population that is changing from

a high r to r=0

Without elephants, some of the grasslands in Africa would eventually become thickets or forests because elephants weed out trees and shrubs. Even though elephants make up a small percentage of the animals living on the grassland, the grassland would eventually cease to exist without them. In this community, elephants are _____.

a keystone species

In nonendothermic animals, small body size is generally correlated with

a lower probability of local extinction

Consider this segment of a food web: Snails and grasshoppers eat pepper plants; spiders eat grasshoppers; shrews eat snails and spiders; owls eat shrews. The snail occupies the trophic level(s) of _____.

a primary consumer

a reduction in numbers of mice.

Which of the following ecosystems would probably have the highest primary productivity? Assume that we are comparing similar sizes of each ecosystem.

a tropical coral reef

The NPP of a community is 150 units per month and the GPP is 240 units per month. If the ecological efficiency of herbivores is 1/6, how many units of plant biomass are converted into biomass of herbivores? a. 25 b. 40 c. 150 d. 900 e. 1,440

a. 25

According to the theory of island biogeography, which type of island would have the highest species diversity? a. A large island near the mainland b. A small island near the mainland c. A small island far from the mainland d. A large island far from the mainland e. An island of any size near the mainland

a. A large island near the mainland

After reading about the changes at Glacier Bay, a student remarks that the pattern and interactions of organisms present at each stage in succession creates the conditions that lead to the pattern present at the next stage. A second student remarks that the soil produced at each stage of succession helps define the pattern present at the next stage. Evaluate these two statements. a. Both statements are accurate. b. The first statement is accurate, but the second statement is not accurate. c. The second statement is accurate, but the first statement is not accurate. d. Neither statement is accurate.

a. Both statements are accurate.

There are five species of beetles of roughly equal abundance in a community. A storm substantially reduces the population of one species. This would result in a decrease in species _______ and no change in species _______. a. diversity; richness b. diversity; evenness c. evenness; diversity d. richness; diversity e. richness; evenness

a. diversity; richness

The value of ecosystem services depends greatly on an ecological factor that humans can maintain with careful management. This factor is a. species diversity. b. population density. c. climatic conditions. d. trophic interactions. e. species composition.

a. species diversity.

An ecologist measures off a transect running through a park and identifies plants at regular intervals. The transect passes through various types of soils. As she moves through the transect she observes that some plants thin out as new ones appear, but that this change is gradual. This pattern is called a. species turnover. b. a disturbance. c. interspecific competition. d. colonization. e. an ecological transition.

a. species turnover.

Islands that are _______ and _______ the mainland tend to have the most species. a.large; near b. large; far from c. medium-sized; near d. medium-sized; far from e. small; near

a.large; near

An ecologist hypothesizes that predation by a particular owl species is the major factor controlling the population of a particular rabbit species. If this is the case, which of the following population effects could be expected in this rabbit-owl pair?

an increase in the pwl population should cause a fall in the rabbit population

In which of the following situations would you expect to find the largest number of K-selected individuals?

an old-growth forest

it tends to rain more on the windward side of mountains than the leeward side because

as air travels up mountains, it cools. cool air holds less moisture than warm aim, and the excess moisture is dropped as rain on the windward side, resulting in dry air descending on the leeward side

Species richness increases

as we travel southward from the North Pole to the equator.

According to the theory of island biogeography, if the colonization rate is equal to the extinction rate, the species richness is

at equilibrium.

In temperate lakes, the surface water is replenished with nutrients during turnovers that occur in the

autumn and spring.

Air masses formed over the Pacific Ocean are moved by prevailing westerlies where they encounter extensive north-south mountain ranges, such as the Sierra Nevada and the Cascades. Which statement best describes the changes that these air masses undergo? A) The cool, moist Pacific air heats up as it rises, releasing its precipitation as it passes the tops of the mountains, and this warm, now dry air cools as it descends on the leeward side of the range. B) The warm, moist Pacific air rises and cools, releasing precipitation as it moves up the windward side of the range, and this cool, now dry air mass heats up as it descends on the leeward side of the range. C) The cool, dry Pacific air heats and picks up moisture from evaporation of the snowcapped peaks of the mountain range, releasing this moisture as precipitation as the air cools as it descends on the leeward side of the range. D) These air masses are blocked by these mountain ranges producing high annual amounts of precipitation on the windward sides of these mountain ranges. E) These air masses remain essentially unchanged in moisture content and temperature as they pass over these mountain ranges.

Ecology as a discipline directly deals with all of the following levels of biological organization except A) population. B) cellular. C) organismal. D) ecosystem. E) community.

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

Global warming is the result of a. increased solar activity. b. rising concentration of greenhouse gases. c. rises in ocean levels. d. pollution.

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

The primary goal of conservation biology is to a. maximize the land set aside for wildlife. b. counter the loss of biodiversity. c. estimate the total number of species that exist. d. integrate human culture back into nature.

Two plant species live in the same biome but on different continents. Although the two species are not at all closely related, they may appear quite similar as a result of A) parallel evolution. B) convergent evolution. C) allopatric speciation. D) introgression. E) gene flow.

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

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

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

Which of the following is not an observed effect of global warming on organisms? a. Many butterfly populations have shifted their ranges to the north. b. Some species of birds and frogs now begin their breeding seasons later in the year. c. Many polar bears show signs of starvation as their hunting grounds melt away. d. Corals "bleach" when increased water temperatures cause them to expel their symbiotic algae.

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

Which statement best contrasts environmentalism with ecology? A) Ecology is the study of the environment; environmentalism is the study of ecology. B) Ecology provides scientific understanding of living things and their environment; environmentalism is more about conservation and preservation of life on Earth. C) Environmentalists are only involved in politics and advocating for protecting nature; ecologists are only involved in scientific investigations of the environment. D) Ecologists study organisms in environments that have been undisturbed by human activities; environmentalists study the effects of human activities on organisms. E) Environmentalism is devoted to applied ecological science; ecology is concerned with basic/theoretical ecological science

You are interested in studying how organisms react to a gradient of a variety of abiotic conditions and how they coexist in this gradient. The best location in which to conduct such a study is A) a grassland. B) an intertidal zone. C) a river. D) tropical forest. E) an eutrophic lake.

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

You go out and trap desert gerbils. On your first trapping night, you capture (and mark) 10 gerbils. On your second trapping night, you capture 1000 gerbils, and 5 are marked. How many gerbils do you estimate are in the population? a. 4000 b. 2000 c. 1000 d. Only the gerbils know

b. 2000

Which of the following would not be considered an example of an ecosystem good or service? a. Forests removing excess carbon dioxide from the atmosphere b. Bees pollinating an invasive weed species c. Bacteria metabolizing a substance that poses a health threat to humans or cattle d. Blowflies limiting the population growth of an insect pest species e. Marsh grasses limiting the effects of storm surges from hurricanes

b. Bees pollinating an invasive weed species

What is the difference between species composition of a community and community structure? a. Species composition takes into account the number of species in a community, while community structure does not. b. Community structure takes into account the number of species in a community, while species composition does not. c. Species composition takes into account the abundance of different species in a community, while community structure does not. d. Community structure takes into account the abundance of different species in a community, while species composition does not. e.Species composition and community structure are the same.

b. Community structure takes into account the number of species in a community, while species composition does not.

Which process does not contribute to species composition changes over short periods of time? a. Extinction b. Evolution c. Colonization d. Disturbance e. Climate change

b. Evolution

Which of the following statements about ecological succession is true? a. It leads to a community distinctly different from the original community. b. It leads to a community resembling the original community. c. It occurs rapidly enough that traces of its earliest stages are quickly lost. d. It occurs slowly enough that traces of its earliest stages are difficult to find.

b. It leads to a community resembling the original community.

According to results from the simulation in the tutorial, which island characteristics are associated with the highest species richness? a. Small and close to the mainland b. Large and close to the mainland c. Small and distant from the mainland d. Large and distant from the mainland

b. Large and close to the mainland

Which factor would be most conducive to counting all of the individuals in a population instead of taking a sample? a. Small body size of the individuals in the population b. Relatively stationary individuals c. A large population d. Difficulty distinguishing the boundaries of individuals e. Rapidly moving individuals

b. Relatively stationary individuals

A group of species that coexist and interact with one another in a defined geographic area is a(n) a. ecosystem. b. community. c. niche. d. biome. e. biota.

b. community.

Between 1950 and 1985, half of Central America's tropical forests were cut, and the remainder was scattered in small isolated fragments. Another 19 percent of the forest had disappeared by 2005. A survey of the remaining tropical forest areas would most likely show a. increased species richness. b. decreased species richness. c. decreased extinction rates. d. increased colonization rates. e. increased primary productivity.

b. decreased species richness.

Hadley cell circulation and the Coriolis effect both describe movements of air masses, although there are major differences between the two phenomena. Both processes, however, involve movement a. east and west. b. north and south. c. toward the equator only. d. east only. e. west only.

b. north and south.

Wolves are crucial for maintaining healthy aspen forests because of their effects on a. succession. b. trophic cascades. c. disturbance. d. island biogeography. e. fragmentation.

b. trophic cascades.

The loss of a single species from a community will most often affect community function by affecting the community's a. growth rate. b. trophic interactions. c. physical environment. d. ecological efficiency. e. gross primary productivity.

b. trophic interactions.

Small areas that are home to a large number of threatened species and an exceptional concentration of species found nowhere else on Earth are called

biodiversity hot spots.

All of these factors reduce the efficiency of energy transfer between trophic levels except

biomass stored as fat or starch. True: lack of availability of some biomass heat loss due to maintaining homeostasis. heat loss due to metabolism. indigestibility of some biomass.

The maximum per capita rate of increase for a population that can occur under ideal conditions is the

biotic potential.

A hypothetical community on a barren mid-Atlantic island consists of two fish-eating seabirds (the booby and the noddy), the fungi and microorganisms that live on the birds' dung, a tick that feeds on these two birds, a cactus, a moth that feeds on cast-off feathers, a beetle that lives on dung organisms, and spiders that eat the other arthropods. There are no other plants and no lichens. Which of the following choices incorrectly pairs a member of this assemblage with its position in the trophic structure?

booby, primary consumer

If, over a long period of time, a region that is currently in the temperate seasonal forest biome becomes considerably colder, this region will most likely become

boreal forest

An ecosystem contains

both the living organisms and the abiotic components of the environment.

All of these adaptations are examples of plant defenses against herbivory except

brightly colored flowers

Currently, the single greatest threat to biodiversity is a. the introduction of exotic species. b. overexploitation of populations for food. c. habitat destruction due to humans. d. global warming.

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

In a food web with energy flowing up, a(n) _______ is one trophic level above a primary consumer. a) decomposer b) herbivore c) secondary consumer d) autotroph e) primary producer

Of the following examples of ecological effect leading to an evolutionary effect (→), which is most correct? A) When seeds are not plentiful → trees produce more seeds. B) A few organisms of a larger population survive a drought → these survivors then emigrate to less arid environments. C) A few individuals with denser fur survive the coldest days of an ice age → the reproducing survivors all have long fur. D) Fish that swim the fastest in running water → catch the most prey and more easily escape predation. E) The insects that spend the most time exposed to sunlight → have the most mutations.

Some populations, especially those with high genetic variability and short life spans, may avoid extinction as the climate changes through a. distribution of populations. b. genetic shift. c. evolutionary adaptation. d. feedback inhibition.

The success with which plants extend their range northward following glacial retreat is best determined by A) whether there is simultaneous migration of herbivores. B) their tolerance to shade. C) their seed dispersal rate. D) their size. E) their growth rate.

The three greatest current threats to biodiversity, in order starting with the greatest, are a. habitat loss, overharvesting, and invasive species. b. invasive species, habitat loss, and overharvesting. c. habitat loss, invasive species, and overharvesting. d. invasive species, overharvesting, and habitat loss.

This is something that I struggle with. We know that a vegetarian leaves a smaller ecological footprint than a person who eats meat. Which of the statements below best explains why this is so? a) Fewer animals are slaughtered for human consumption. b) Vegetarians need to ingest less chemical energy than omnivores. c) Eating meat is an inefficient way of acquiring photosynthetic productivity. d) There is an excess of plant biomass in all terrestrial ecosystems. e) Vegetarians require less protein than do omnivores.

Tropical grasslands with scattered trees are also known as A) taigas. B) tundras. C) savannas. D) chaparrals. E) temperate plains

Using living organisms to clean up polluted ecosystems is known as a. PVA. b. landscaping. c. bioremediation. d. biological demagnification.

Where would an ecologist find the most phytoplankton in a lake? A) profundal zone B) benthic zone C) photic zone D) oligotrophic zone E) aphotic zone

Which of the following abiotic factors has the greatest influence on the metabolic rates of plants and animals? A) water B) wind C) temperature D) rocks and soil E) disturbances

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

Which of the following statements about ecology is incorrect? A) Ecologists may study populations and communities of organisms. B) Ecological studies may involve the use of models and computers. C) Ecology is a discipline that is independent from natural selection and evolutionary history. D) Ecology spans increasingly comprehensive levels of organization, from individuals to ecosystems. E) Ecology is the study of the interactions between biotic and abiotic aspects of the environment

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

The GPP of a community is 40 units per day on average, while the NPP of the community is 15 units per day. How many units are used for cellular respiration and other catabolic processes of the plants? a. 0 b. 15 c. 25 d. 40 e. 55

c. 25

Which community has the highest species diversity? a. Community 1, with three equally abundant species b. Community 2, with an uneven distribution of four species c. Community 3, with four equally abundant species d. Communities 2 and 3, with equal species diversity e. All three communities have equal species diversity.

c. Community 3, with four equally abundant species

At Glacier Bay, Alaska, why were Dryas (an herbaceous plant) and alder trees among the first plants to appear during the ecological succession of gravel deposits left behind by a retreating glacier? a. Dryas and alder trees grow well on rocky soil. b. The seeds of Dryas and alder trees are easily transported to gravel deposits. c. Dryas and alder trees have nitrogen-fixing bacteria in nodules on their roots. d. Dryas and alder trees are the most abundant plants that grow in that area.

c. Dryas and alder trees have nitrogen-fixing bacteria in nodules on their roots.

Artificially constructed movement corridors

can be harmful because they allow for the spread of disease.

Fire suppression by humans

can change the species composition within biological communities.

Most plants have a variety of chemicals, spines, and thorns because the plants

cannot run away from herbivores.

Which of the following substances is cycled between organic matter and abiotic reservoirs?

carbon

Which substance is cycled between organic matter and abiotic reservoirs?

carbon

Greenhouse gases include

carbon dioxide and methane.

Population size is believed to level off at the _______ of an environment.

carrying capacity

The maximum number of individuals a habitat can support is called its

carrying capacity

When a population stops changing size, it has reached ________, and r = _________. carrying capacity, 1 carrying capacity, 0 logistic growth, 1 logistic growth, 0

carrying capacity, 0

Which of the following is an example of a commensalism?

cattle egrets eating insects stirred up by grazing bison

During ecological succession, the species composition of a plant community generally

changes gradually because each species responds differently to the changing environment.

An example of commensalism is

clown fishes in sea anemones.

A series of reciprocal evolutionary adaptations in two species is called _____.

coevolution

Some herbivore-plant interactions evolved through a series of reciprocal evolutionary adaptations in both species. The process is called

coevolution.

Some herbivore-plant interactions evolved through a series of reciprocal evolutionary adaptations in both species. This process is called

coevolution.

Most of the world's deserts are located at latitudes where

cold, dry air moving toward the poles descends.

Tropical orchids grow into tree bark in rainforests. They require the trees for support and obtain nutrients from debris on the bark, but they do not harm the trees. This interaction demonstrates _______, and the interaction between orchids and trees can be described as _______.

commensalism; +/0

A form of symbiosis in which one participant benefits and the other apparently is not benefited nor harmed is

commesalism

"Understanding how the introduction of pythons in Everglades National Park influences the diversity of alligator populations" is an example of what scale of ecological organization?

community

NPP and NPP are most closely associated with

community function.

An owl and a hawk both eat mice. Which of these describes the relationship between a hawk and an owl?

competition

There are two organisms with overlapping ranges and filling a similar niche. We find that where their niches overlap, there is twice the competition for resources. This leads to

competitive exclusion

Uniform spacing patterns in plants such as the creosote bush are most often associated with

competitive interaction between individuals of the same population.

The growing season would generally be shortest in which of the following biomes?

coniferous forest

Which of the following biomes, dominated by cone-bearing evergreen trees, is the largest terrestrial biome?

coniferous forest

Which of the following biomes is dominated by coniferous trees adapted to surviving long, harsh winters and short, wet summers?

coniferous forests

If more biomass is locked up in forms that cannot be accessed and ingested by primary consumers in a forest vs. grassland ecosystem, this would likely affect consumption efficiency assimilated efficiency production efficiency none of the above

consumption efficiency

In a broader definition of metapopulation than that of Ilkka Hanski, a ________ population may have a low probability of extinction and supply ________ populations with immigrants

core, satellite

Coral reefs can be found on the southern east coast of the United States but not at similar latitudes on the southern west coast. Differences in which of the following most likely account for this? A) sunlight intensity B) precipitation C) day length D) ocean currents E) salinity

Greenhouse gases include a. carbon dioxide and nitrogen. b. nitrogen and oxygen. c. nitrous oxide and oxygen. d. carbon dioxide and methane.

In which community would organisms most likely have adaptations enabling them to respond to different photoperiods? A) tropical forest B) coral reef C) savanna D) temperate forest E) abyssal

Movement corridors a. reduce dispersal. b. can be harmful because they allow for gene flow. c. increase inbreeding. d. can be harmful because they allow for the spread of disease.

One way in which populations and species have been responding to climate change is by a. changing their metabolism. b. evolving a flexible mode of reproduction. c. changing their coat color. d. shifting their distribution.

Probably the most important factor(s) affecting the distribution of biomes is (are) A) wind and ocean water current patterns. B) species diversity. C) proximity to large bodies of water D) climate. E) day length and rainfall

Protecting the endangered black-footed ferret from extinction involved a. vaccinating the remaining population against sylvatic plague. b. providing food during harsh winters. c. collecting individuals from multiple small populations and combining them into a single large population. d. captive breeding and reintroduction.

Scientists worry that global warming will result in the oceans a. becoming more basic. b. containing less dissolved oxygen. c. containing less dissolved carbon dioxide. d. becoming more acidic.

Species introduced to new geographic locations A) are usually successful in colonizing the area. B) always spread because they encounter no natural predators. C) increase the diversity and therefore the stability of the ecosystem. D) can out-compete and displace native species for biotic and abiotic resources. E) are always considered pests by ecologists

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

The Kissimmee River Project is intended to a. provide areas for homes and businesses. b. restrict ecotourism and other recreational usage in the impacted region. c. drain natural wetlands in the central Florida region. d. increase biodiversity of the region.

The Yukon to Yellowstone Initiative is a plan to a. connect all of the national parks in the western United States. b. create a giant, fenced, private land area between the national parks in the United States to create a protected zone for wildlife. c. connect all of the national parks in the United States. d. connect parks in the United States and Canada with protected corridors where wildlife can travel safely.

The introduction of wolves into Yellowstone National Park in 1991 resulted in a. a general decline in overall habitat as death spread like wildfire. b. the migration of most of these wolves out of the park and back to Canada. c. the death of all of the wolves, likely due to an insufficient amount of available prey. d. ecological changes involving at least 25 species.

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

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

Which of the following is a likely consequence of the thinning of the ozone layer? a. decreases in flying insect populations b. increases in escape of heat from Earth c. global warming d. increases in skin cancer

You spray your lawn with a pesticide. The concentration of the pesticide in the tissues of the grass on your lawn is 10-6 parts per million (ppm). Grasshoppers eat the grass and are in turn eaten by rats, which are then eaten by owls. At each successive trophic level, the concentration of pesticides increases. The term for this process is a. biological extirpation. b. trophic concentration. c. bioconcentration. d. biological magnification.

Who will receive the ball while the merry-go-round is in motion? counterclockwise. a. Ball caught by the thrower b. Ball caught opposite thrower c. Ball caught to thrower's left d. Ball caught to thrower's right

d. Ball caught to thrower's right

Earthworm activity adds nutrients and oxygen to the soil and makes it more homogenous. Thus, this soil has more value for agriculture. Which term best describes the agricultural value of earthworms? a. Disturbance b. Species evenness c. Species turnover d. Ecosystem service e. Succession

d. Ecosystem service

Suppose that in a study of an ecological community, NPP increases as species richness increases, but scientists find no relationship between NPP and the number of functional roles played by the species. Which conclusion could be inferred? a. Ecological efficiency of the community is high. b. Ecological efficiency of the community is low. c. Tilman and his colleagues drew the wrong conclusions from their study of prairie communities. d. Niche complementarity does not explain the richness-productivity relationship in this community. e. Niche complementarity explains much of the richness-productivity relationship in this community.

d. Niche complementarity does not explain the richness-productivity relationship in this community.

A tsunami strikes a large peninsula, destroying the bird populations living there. The tsunami also fragments the peninsula into three islands of similar size but different distances from the mainland. What would the MacArthur-Wilson model predict about bird populations on these islands in the future? (Assume that birds do not migrate between islands.) a. Eventually, the number of bird species inhabiting the islands will be the same, although the amount of time it takes for this to be established on each island will differ. b. Eventually, the rates of colonization and extinction of birds on all of the islands will be the same, although the amount of time it takes for this to be established on each island will differ. c. The number of bird species will be constant across all islands as a consequence of their similar sizes. d. The rates of colonization of bird species will decrease with increasing distance of the island from the mainland, leading to lesser diversity with distance.

d. The rates of colonization of bird species will decrease with increasing distance of the island from the mainland, leading to lesser diversity with distance.

In 2011, a tornado tore through Springfield, Massachusetts, destroying a large proportion of the trees in the area. This event is an example of _______, and the subsequent growth of new trees is an example of _______. a. ecological transition; niche recovery b. ecological transition; community flux c. disturbance; niche recovery d. disturbance; succession e. community flux; succession

d. disturbance; succession

A researcher is comparing the heights of the tallest plants found in communities where pollinators are abundant to those in communities where pollinators are scarce. The researcher is testing whether there is a relationship between _______ and pollinators. a. succession b. species richness c. community structure d. habitat structure e. niche breadth

d. habitat structure

An animal would most likely rely on fixed action patterns of behavior if it a. had babies with very large brains. b. had babies with very poor sensory organs. c. had behaviors that were simple, but need to be varied. d. laid eggs and left before they hatched. e. had babies that required an extended period of parental care.

d. laid eggs and left before they hatched

You are a scientist designing an experiment to investigate NPP over large expanses of Earth's surface. Which of the following could be measured by satellite to correlate with NPP? a. Water content of biomass b. Ground cover by native plants c. Distribution of primary consumers d.Sunlight absorption by chlorophyll e. Carbon content of organismal biomass

d.Sunlight absorption by chlorophyll

In the logistic growth model, as population size increases, birth rates

decline and/or death rates increase

As a growing population nears its carrying capacity, birth rates

decline and/or death rates increase.

biodiversity has been ______ over time because of _______ activities.

declining; human

Through the end of the century, the global population growth rate is predicted to _________, and doubling times are predicted to ____________. increase, increase increase, decrease decrease, increase decrease, decrease

decrease, increase

As a population nears its carrying capacity, its per capita birth rate (b) would _______ and its per capita death rate (d) would _______.

decrease; increase

An ecologist recorded 12 white-tailed deer, Odocoileus virginianus, per square mile in one woodlot and 20 per square mile in another woodlot. What was the ecologist comparing?

density

Assume that there are five alligators per acre in a swamp in northern Florida. This is a measure of the alligator population's

density

Which of the following sets of measurements would best describe a population's physical structure and vital statistics?

density, dispersion, and demographics

A tidal wave wipes out the entire population of mice living on an island. This is an example of

density-independent effect

Generally speaking, deserts are located in places where air masses are usually

descending

Deserts typically occur in a band around 30 degrees north and 30 degrees south latitude because

descending air masses originating from the tropics tend to be dry.

Deserts typically occur in a band at 20 degrees north and south latitude because

descending air masses tend to be cool and dry.

Deserts typically occur in a band at 30 degrees north and south latitude or at different latitudes in the interior of continents. This supports the idea that

descending air masses tend to be dry.

species are found within a community because they have similar habitat needs

describes an open community

Which of the following correctly lists the biomes in order from lowest precipitation (at the left) to highest precipitation (to the right)?

desert, tundra, temperate broadleaf forest, tropical rain forest

Studying species transplants is a way that ecologists

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

Studying species transplants is a way that ecologists

determine if dispersal is a key factor in limiting the distribution of organisms.

Population ecologists follow the fate of same-age cohorts to

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

An understanding of population abundance would be least important to people attempting to

determine what insects the praying mantis eats

the population densities of skunks in western Massachusetts vary considerably from year to year; therefore, skunk density is

dynamic

Imagine some cosmic catastrophe jolts Earth so that its axis is perpendicular to the orbital plane between Earth and the sun. The most obvious effect of this change would be A) the elimination of tides. B) an increase in the length of night. C) an increase in the length of a year. D) a decrease in temperature at the equator. E) the elimination of seasonal variation.

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

Landscape ecology is best described as the study of A) the flow of energy and materials between the biotic and abiotic components of an ecosystem. B) how the structure and function of species enable them to meet the challenges of their environment. C) what factors affect the structure and size of a population over time. D) the interactions between the different species that inhabit and ecosystem. E) the factors controlling the exchanges of energy, materials, and organisms among ecosystem patches.

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

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

Which of the following causes Earthʹs seasons? A) global air circulation B) global wind patterns C) ocean currents D) changes in Earthʹs distance from the sun E) the tilt of Earthʹs axis

Which of the following environmental features might influence microclimates? A) a discarded soft-drink can B) a tree C) a fallen log D) a stone E) all of the above

Which of the following organisms is the most likely candidate for geographic isolation? A) sparrow B) bat C) squirrel D) salt-water fish E) land snail

ʺHow does the foraging of animals on tree seeds affect the distribution and abundance of the trees?ʺ This question A) would require an elaborate experimental design to answer. B) is difficult to answer because a large experimental area would be required. C) is difficult to answer because a long-term experiment would be required. D) is a question that a present-day ecologist would be likely to ask. E) A, B, C and D are correct.

Under stress, a community loses a number of species. When the stress is removed, the species composition recovers and then stabilizes. During this process, what will be the most likely effect on net primary productivity? a. It will increase. b. It will decrease. c. It will be unaffected. d. It will increase and then stabilize. e. It will decrease, recover, and then stabilize.

e. It will decrease, recover, and then stabilize.

Which statement is supported by the MacArthur-Wilson model simulation? a. Only large islands or islands close to the mainland reach equilibrium between colonization and extinction rates. b. With time, colonization rates go up and extinction rates go down, leading to an equilibrium characterized by no net change in species richness. c. Eventually, no matter the size of an island or its distance from the mainland, the rates of colonization and extinction of species reach zero. e. Species diversity depends on the rates of colonization and extinction, which depend on the size and location of an island.

e. Species diversity depends on the rates of colonization and extinction, which depend on the size and location of an island.

The number of trophic levels in communities is limited by a. predation. b. succession. c. competitive exclusion. d. the presence of decomposers. e. the loss of energy between trophic levels

e. the loss of energy between trophic levels

Species richness is highest in the a.temperate region of the Northern hemisphere. b. subtropic region of the Northern hemisphere. c. temperate region of the Southern hemisphere. d. subtropic region of the Southern hemisphere. e. tropics.

e. tropics.

Replacement reproduction occurs when

each couple has an average of two children, but may still allow for population growth.

In large natural ecosystems, competition between two species over time will usually result in

each species occupying a slightly different niche.

The questions of how chemicals flow and energy cycles between organisms and their surroundings are addressed in the study of which level of ecological organization?

ecosystem

Which of the following levels of ecological organization is arranged in the correct sequence from most to least inclusive?

ecosystem, community, population, individual

Which of the following levels of organization is arranged in the correct sequence from most to least inclusive?

ecosystem, community, population, individual

An area in which different terrestrial biomes grade into each other is known as a(n)

ecotone.

A survivorship curve that involves producing very few offspring, each of which has a high probability of surviving to adulthood, is typical of

elephants

Which series is correctly layered from top to bottom in a tropical rain forest?

emergent layer, canopy, under story, shrub/immature layer, ground layer

When growth proceeds at a rate similar to 2 → 4 → 8 → 16 → 32 → 64...etc., it is called

exponential growth.

Metapopulation persistence is a dynamic balance between the _____ of local populations and the _____ of empty habitat patches.

extinction, recolonization

Which of the following describes a successional event in which one organism makes the environment more suitable for another organism?

facilitation

Which of the following terms is used by ecologists to describe the community interaction in which one organism makes the environment more suitable for another organism?

facilitation

The theory that plants cannot grow on a particular area until the soil has been developed enough by an earlier community is the

facilitation model

Flatback Island should have a higher colonization rate than Hawksbill Island. True False Cannot be determined

false

energy can be transferred, transformed, and destroyed.

false

fragment size does not influence species composition or diversity

false

In a biogeochemical cycle, a pool can remain balanced (that is, not increase or decrease in size) only if rates of flux remain constant. fluxes into the pool equal fluxes out of the pool. fluxes out of the pool remain the same size. fluxes into the pool remain the same size.

fluxes into the pool equal fluxes out of the pool.

Which of the following environmental features might influence microclimates?

forest canopy freshly plowed field log on the forest floor large boulder All of the options are correct.

which example best describes both an elemental pool where an element accumulates and an elemental sink where it is removed from circulation and locked up for long periods?

fossil fuel deposits in which carbon is stored for hundreds of millions of years

In your backyard, you overturn a large rock. In the damp soil underneath the rock, you see various insects scurrying for cover: one black spider, five black ants, two brown beetles, and three gray pillbugs. In this community of organisms, species richness is represented by

four different species of organisms.

The main detritivores in an ecosystem are _____.

fungi and prokaryotes

one reason that apple maggot flies are distributed in patches is that they feed off of apple, hawthorn, and other similar tress, which themselves are not evenly distributed. these trees represent ______ for the flies

habitats

Natural selection involves energetic trade-offs between

high survival rates of offspring and the cost of parental care.

Species differ widely in their susceptibility to local extinction and their ability to colonize available habitats. Plant species that reproduce asexually tend to have relatively ____ rates of growth and subsequent _____ rates of local extinction.

high, lower

A species of malaria-carrying mosquito lives in a forest in which two species of monkeys, A and B, coexist. Species A is resistant to malaria, but species B is not. The malaria-carrying mosquito is the chief food for a particular kind of bird in the forest. If all these birds were suddenly eliminated by hunters, which of the following would be an immediate observable consequence?

increased mortality in monkey species B

Refer to the equation below. N=Nt+B-D An elk population begins the year with 125 members. During the year, 40 elk are born and 27 die. By the end of the year, the population has

increased to 138

In metapopulations, the rate of local population colonization ________ as the proportion of patches occupied increases.

increases and then decreases

Which ocean zone describes the interface between ocean and land?

intertidal

Which of the following is most likely to contribute to density-dependent regulation of populations?

intraspecific competition for nutrients

Two species are most likely to coexist despite competition between them when

intraspecific competition is stronger than interspecific competition.

A population is growing, and its density increases rapidly, but its food source becomes limiting. The per capita growth rate (r) decreases and the population eventually stops growing and fluctuates around its carrying capacity. The interaction that led to this change in growth rate was

intraspecific competition.

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

The relationship between ecosystem type and net primary productivity (NPP) in Earth's ecosystems

is variable, with some ecosystems responsible for disproportionately more NPP.

Which pattern of reproduction is correctly paired with a species?

iteroparity-elephant

Which pair of terms most accurately describes life history traits for a stable population of wolves?

iteroparous; K-selected

biodiversity is high in all of the following situations EXCEPT

low intensity of disturbance

A __________ is a collection of local populations that interact within a region.

metapopulation

the larger population that is composed of many sub-populations is known as a

metapopulation

Based on the intermediate disturbance hypothesis, a community's species diversity is increased by

moderate levels of disturbance.

The biggest difference between the flow of energy and the flow of chemical nutrients in an ecosystem is that _____.

nutrients are recycled, but energy is not

A positive per capita growth rate

occurs when the per capita birth rate is greater than the per capita death rate

Coral reefs can be found on the southern east coast of the United States but not at similar latitudes on the southern west coast. Differences in which of the following most likely account

ocean currents

Which of the following is characteristic of K-selected populations?

offspring with good chances of survival

Introduced species

often fail to colonize the new area. may become common enough to become pests. can disrupt the balance of the natural species with which they become associated.

The benthic zone in an aquatic biome

often supports communities of organisms that feed largely on detritus.

you are managing a metapopulation of a threatened beetle that lives on a plant that is found in patches. because of the distribution of its host plant, the beetle is also found in patches, and these patches vary in size. if you are faced with limited resources and cannot attempt to save all of the beetle sub-populations, where should you concentrate your efforts, and why?

on the largest patches, because these have the highest potential to reseed the other patches

based on what you have read about metapopulation dynamics in Edith's checkerspot butterflies, which statement is most likely to be true?

patches near occupied patches can be colonized more readily than ones farther away

A sperm whale in the middle of the Atlantic Ocean is in which oceanic zone?

pelagic

The major cause of tropical deforestation is

people clearing forests to open up land for agriculture

The major reason for tropical deforestation is ________.

people clearing forests to open up land for agriculture.

The number of offspring produced by the average individual in a population is known as the

per capita birth rate

In the models that describe population growth, r stands for _____.

per capita population growth rate

The factor(s) that help to perpetuate temperate grasslands, such as the American prairies, and prevent them from becoming woodlands include

periodic drought and fires.

Trees are not usually found in the tundra biome because of

permafrost

Where would an ecologist find the most phytoplankton in a lake?

photic zone

On Earth, most organic molecules are produced by

photosynthesis.

Earth's biosphere is not completely self-contained (or closed) because _____

plants, algae, and photosynthetic bacteria obtain energy from sunlight, and heat escapes from the biosphere into space

A community is composed of

potentially interacting populations of different kinds of organisms.

Interaction between two species in which one feeds on the other is

predation

Which of the following are important biotic factors that can affect the structure and organization of biological communities?

predation, competition

Camouflage typically evolves as a result of

predation.

One simple thing that you can do to help safeguard the environment is to eat a diet consisting only of

producers

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 nocturnal. You have discovered an example of

resource partitioning.

Two species of plants that are competitors in nature are grown together in the greenhouse. When they are fed additional nitrogen, species A thrives at the expense of species B. When they are fed additional phosphorus, species B thrives at the expense of species A. Both species show improved growth when they are both given additional sunlight, but additional moisture has little effect on either one. Based on this information, which of the following is most likely to be the limiting resource for both species?

sunlight

The main reason polar regions are cooler than the equator is that

sunlight strikes the poles at a lower angle.

In many dense forests, plants living near the ground level engage in intense competition for

sunlight.

In mountainous areas of western North America, north-facing slopes would be expected to

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

In mountainous areas of western North America, north-facing slopes would be expected to

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

An individual's fitness is measured by its ability to

survive and reproduce

Resource partitioning would be most likely to occur between

sympatric populations of species with similar ecological niches.

The growing season would generally be shortest in which of the following biomes?

taiga

Which of the following biomes is dominated by gymnosperm or conifer trees (pines, firs, spruces)?

taiga

In a food chain consisting of phytoplankton → zooplankton → fish → fishermen, the fishermen are

tertiary consumers.

The main cause of the recent increase in the amount of carbon dioxide in Earth's atmosphere is _____.

the burning of larger amounts of wood and fossil fuels

Which of the following might be an investigation of microclimate?

the effect of sunlight intensity on species composition in a decaying rat carcass

A tidal wave wipes out the entire population of mice living on an island. This is an example of

the effects of abiotic factors

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 b

the elimination of seasonal variation.

Gross primary productivity (GPP) and net primary productivity (NPP) are both rates relating to energy use by producers. The key difference between them is that GPP represents

the energy capture rate, while NPP represents the energy conversion rate.

in general, solar radiation is most intense at

the equator

Suppose a survey of predator-prey relationships where the predators were large mammals shows that the fastest predators are usually found in regions where the fastest prey are also found. The most likely explanation for such a finding would be

the existence of evolutionary arms races

The presence of a species in a particular place, and its ability to reproduce there, implies that __________

the species is (or was) adapted to the type of abiotic and biotic environmental conditions found at that location

In the development of terrestrial biomes, which factor is most dependent on all the others?

the species of colonizing animals

What is the highest hierarchical level of the population concept?

the species' geographical range

Habitat

the specific environment an organism lives in, including the biotic and abiotic factors present in its surroundings.

Which of the following causes Earth's seasons?

the tilt of Earth's axis

The success with which plants extend their range northward following glacial retreat is best determined by

their seed dispersal rate.

Which of the following is characteristic of most terrestrial biomes?

vegetation demonstrating vertical layering

While habitat destruction by humans creates fragmented ecosystems, fragmentation can also occur due to natural processes. Which natural process would most likely create a fragmented ecosystem?

volcanic eruption

An ecologist hypothesizes that predation by a particular owl species is the major factor controlling the population of a particular rabbit species. The first step in testing this hypothesis would be to determine

whether the owls eat the rabbits

Consider that a species of salmon lays 20,000 eggs per pair when it spawns and dies. At the end of five years, an average of one pair of mature salmon from this group of hatched eggs returns again to spawn in the parent stream (19,998 have died). What is the per capita rate of increase?

Biology Chapter 44 (Ecological Communities), CH37-COMMUNITY AND ECOSYSTEM ECOLOGY, test 5, BSC2011 Exam 3, Learning Catalytic's Ecology Section, Chapter 38, Exam 3 Multiple Choice, Chapter 54 Community Ecology, Chapter 37, Bio HW 6 (Ch. 38), Ch 54, C...

Related study sets

endocraine and metabolic disorders

Sociology Ch 7

Respiratory and GI

毗斯迦山旧约第5部分—先知书概览

python method - strftime()

mgt420 study

Chapter 65

Leadership

mgmt exam 3

Practice Exam Testing 1

chapter 7 personal finance

bust cum final

9 клас карпюк Magic Box

I-I-I MEDS EAQ

FNP590 Final

ADN 240 Exam 2 PP / Newborn MC

Math Vocabulary.1

heme pre-lecture questions all lectures

Buisness chapter 5

ECON 2101 Test 4 Review