Ecology Test 3 Practice Questions

In the southeastern United States, marshes are dominated by two species of smooth cordgrass; Spartina alterniflora dominates the seaward edge of the marsh, while Spartina patens dominates the high marsh. You work with researchers and determine that if S. patensis is removed from the high marsh, S. alterniflora will occupy all of the marsh, into the high marsh. If, however, S. alterniflora is removed from the seaward side of the marsh, S. patens will only grow a small portion further seaward, and it does not seem to tolerate being submerged for long periods during high tide. Which of the following is a conclusion you can draw based on this experiment? The experiment indicates that S. alterniflora is a superior competitor and that is why it is found on the seaward side of marshes. The fundamental niche of S. alterniflora is expanded by its mutualistic relationship with S. patens. When S. patensis is removed, S. alterniflora can grow in all areas of its fundamental niche, indicating that its distribution is limited by competition to a smaller realized niche. S. alterniflora is prevented from colonizing the high marsh under normal growing conditions due to predation, resulting in a more seaward realized niche. When S. alterniflora is removed, S. patens can grow in all areas of its fundamental niche, indicating that its distribution is limited by competition to a smaller realized niche.

When S. patensis is removed, S. alterniflora can grow in all areas of its fundamental niche, indicating that its distribution is limited by competition to a smaller realized niche.

Simpson's index of diversity ranges between __________ and __________, with __________ values indicating greater diversity. -1, 1, higher 0, 1, higher 0, 1, lower 0, species evenness of a community, higher 0, species evenness of a community, lower

0, 1, higher

The relative abundance of a tree with 100 individuals in a community of 1000 would be 10. 1. 0.1. 100.

0.1.

If herbivores eat 1000 kcal of plant energy, approximately how much energy will be converted into the tissues of herbivores? 10 kcal 1 kcal 100 kcal 1000 kcal

100 kcal

Tiger sharks consume 2000 kg of green sea turtles over the course of the summer months in a subtropical bay. Based on the average rate of trophic efficiency, approximately how much tiger shark biomass will be produced by predation on turtles? 200 kg 1000 kg 2000 kg 2 kg 100 kg

200 kg

If there is a single species (species 1) present with the carrying capacity of 500, and another competing species (species 2) with the same limiting resource becomes established in the area and has a population of 200, it will effectively change the carrying capacity for species 1 to __________. 200 500 700 300 250

300

Suppose that a system has 5000 grasshoppers. How many hawks would be expected? (Fig 3) 5 50 500 5000

50

An ecologist studying productivity in a sample of grasses measures gross primary productivity as 1000 kcal/m2/yr and autotrophic respiration as 100 kcal/m2/yr. Based on these calculations, the net primary productivity would be 10,000 kcal/m2/yr. 1100 kcal/m2/yr. 10 kcal/m2/yr. 900 kcal/m2/yr.

900 kcal/m2/yr.

Which is an example of secondary succession? A farmer allows an agricultural field to return to native grassland. A shift in river flow introduces sediment to a rocky area. Beach grasses colonize a newly formed sand dune. Retreating glaciers leave alluvial soils for cottonwood trees to colonize.

A farmer allows an agricultural field to return to native grassland

Which of the following statements about competition among plant species is FALSE? Competition among plants rarely involves only one resource. Environmental gradients influence the outcome of competition among plants. Plants compete both aboveground and belowground. Along a resource gradient in terrestrial environments, the lower boundary of a plant species is determined by competition, and the upper boundary is determined by stress tolerance. The competitive ability of plants is determined primarily by their growth rate and ability to acquire resources.

Along a resource gradient in terrestrial environments, the lower boundary of a plant species is determined by competition, and the upper boundary is determined by stress tolerance.

Which of the following statements is FALSE? Areas with high mean annual temperatures have longer growing seasons than do areas with lower temperatures, but the rate of photosynthesis is similar. The growing season is the period when temperatures are high enough to support photosynthesis. The availability of water limits the rate of photosynthesis because stomata must be opened to gather carbon dioxide. Water availability and temperature interact to influence photosynthesis rates. Net primary productivity increases with increasing mean temperature and rainfall

Areas with high mean annual temperatures have longer growing seasons than do areas with lower temperatures, but the rate of photosynthesis is similar.

Which of the following is an example of coevolution? Certain species of caterpillars feed on cilantro. When the cilantro leaves are bitten, they release a chemical that attracts wasps that are parasitoids of the caterpillar. The plants that don't produce the chemicals attracting the wasps incur more herbivory and produce fewer seeds, while those that produce the chemicals and attract the parasitoids have higher fitness. The wasps that aren't able to detect the chemicals have far lower larval survival; thus, they have lower reproductive success. Black rat snakes live in trees and are able to feed on nestling birds and small rodents that live in trees. A rabbit with lighter colored fur evades predation in winter. Birds with longer beaks are able to survive a drought better than birds with short beaks, but the birds with short beaks are more efficient at consuming seeds. A bee pollinates many species of flowers, visiting each in turn and collecting pollen.

Certain species of caterpillars feed on cilantro. When the cilantro leaves are bitten, they release a chemical that attracts wasps that are parasitoids of the caterpillar. The plants that don't produce the chemicals attracting the wasps incur more herbivory and produce fewer seeds, while those that produce the chemicals and attract the parasitoids have higher fitness. The wasps that aren't able to detect the chemicals have far lower larval survival; thus, they have lower reproductive success.

Which of the following statements about community structure is FALSE? Coastal marine communities are defined based on their plant life. Open-ocean communities are defined largely by the amount of light that penetrates to a particular depth. Terrestrial communities are often classified by their dominant plant life. Communities have a vertical structure. Community structure can reflect abiotic factors.

Coastal marine communities are defined based on their plant life.

Which of the following statements supporting the argument that competition is extremely important in ecological systems is FALSE? Coexisting species are always engaged in competitive interactions. Competitor species show niche differentiation in space, time, and/or diet. Competitors show negatively associated distributions. Coexisting species that utilize the same resources within habitats may coexist by partitioning those resources. Competitive release has been documented in a number of areas.

Coexisting species are always engaged in competitive interactions.

Which of the following statements about zonation is FALSE? Salinity is a major gradient that influences zonation in estuaries. Zonation can be a product of the trade-off between the ability to tolerate stress and competitive ability. Zonation is the result of variation in resources and non-resource factors. Regional patterns of plant distributions are largely driven by climate. Competition is the only biological factor that influences patterns of zonation.

Competition is the only biological factor that influences patterns of zonation.

Which of the following statements about changes in species diversity during succession is true? Comparing groups of sites, known as temprosequences, that are at different stages of succession can give insights into changes in diversity through succession. Patterns of diversity are decoupled from patterns of environmental conditions. Diversity tends to peak very early in succession. Diversity peaks are associated with transitions in species composition. Diversity reaches its peak at the climax community.

Diversity peaks are associated with transitions in species composition.

Which of the following statements is FALSE? Preemptive competition occurs primarily among sessile organisms. Allelopathy in plants is a form of chemical competition. Consumption competition involves individuals of one species inhibiting another through consumption of a common resource. In overgrowth competition, one species limits another's access to a resource by growing over it. Encounter competition is the behavioral exclusion of others from a specific defended space.

Encounter competition is the behavioral exclusion of others from a specific defended space

Fig 1

Fig 1

Fig 4 put steps in order

Fig 4

Which of the following statements about biological communities is true? Trade-offs faced by individual community members have little impact on community structure. Experiments that focus on interactions among a small number of species are likely to overestimate the importance of species' interactions in structuring communities. Species interactions have only minor impacts on community structure. Intraspecific competition often results in the exclusion of species from a community. Fundamental niches represent a primary constraint on the species present in a community.

Fundamental niches represent a primary constraint on the species present in a community.

Which of the following formulas are correct regarding productivity? NPP - R = GPP GPP + R = NPP NPP - GPP = R GPP - R = NPP

GPP - R = NPP

What is the outcome of these isoclines? (Fig 2) Both species coexist. Species 2 wins. If species 1 begins with a higher abundance, it wins. Species 1 wins.

If species 1 begins with a higher abundance, it wins.

You are studying the effects of nitrogen enrichment on a series of small ponds on your campus. You are careful to add only small amounts of nitrogen and measure the net primary productivity as chlorophyll content. You can see the bottom of all of the ponds in the study and they are experimental ponds, all of roughly the same size. Please choose the appropriate description of a graph of your data. With total nitrogen on the x-axis and amount of chlorophyll on the y-axis, you would see a decreasing straight line illustrating a negative relationship between these variables. There would not be a relationship between the amount of nitrogen and the total nitrogen. It would be a scatterplot with no discernable pattern. With amount of chlorophyll on the x-axis and total nitrogen on the y-axis, you would see an increasing straight line illustrating a positive relationship between these variables. With total nitrogen on the x-axis and amount of chlorophyll on the y-axis, you would see an increasing straight line illustrating a positive relationship between these variables. With amount of chlorophyll on the x-axis and total nitrogen on the y-axis, you would see a decreasing straight line illustrating a negative relationship between these variables.

With total nitrogen on the x-axis and amount of chlorophyll on the y-axis, you would see an increasing straight line illustrating a positive relationship between these variables.

The removal of a keystone species from a community will initiate changes in that community's structure and typically results in __________. a significant increase in diversity unpredictable changes in diversity no change in diversity or abundance of species no significant change in diversity a significant loss of diversity

a significant loss of diversity

Plant community structure along an environmental gradient can often be explained by differences among species in their competitive abilities. differences among species in their resistance to herbivores. a trade-off among species with respect to competitive ability and stress tolerance. differences among species in their abilities to tolerate stress.

a trade-off among species with respect to competitive ability and stress tolerance.

The diagonal line that represents dN/dt = 0 in the graphical depiction of the Lotka-Volterra competitions equations is called a competition coefficient. a zero-growth isocline. a competitive exclusion parameter. the carrying capacity.

a zero-growth isocline

Which of the following organisms have benefited from wolf reintroduction? beavers woody plant species grizzly bears all of the above

all of the above

Which of the following is an example of a fundamental niche? a bird nesting on top of a tree in the presence of predators a lizard feeding on insects only at dawn when snakes are present a mouse feeding on only small seeds in the presence of a competitor an amphibian laying eggs in all possible habitats

an amphibian laying eggs in all possible habitats

In a food web, an example of an intermediate species is __________. a primary producer an herbivore algae an autotroph a top carnivore

an herbivore

Wolf reintroduction in Yellowstone decreased elk populations due to predation. Researchers have found that this has led to __________. no effect on aspen trees as they are not the primary food of elk a regrowth of willow trees that led to a decrease in bird species diversity a decline in beaver populations due to increased predation by wolves an increase in berry-producing shrubs and a positive impact on invertebrate species that feed on these berries a purely negative impact on the grizzly bear population in Yellowstone

an increase in berry-producing shrubs and a positive impact on invertebrate species that feed on these berries

Coastal brown bears in southeastern Alaska have to take advantage of a variety of resources. In the spring they eat sedges and berries, but later in the year they begin eating salmon and other meat. The coastal brown bear is an example of __________. an omnivore an intraguild predator an apparent competitor with salmon a first-level consumer a specialist

an omnivore

Which of the following provides evidence for the hypothesis that coyote range expansion is the result of competitive release? In a series of field studies, researchers examined the relationship between gray wolves and coyotes in Yellowstone National Park using radio-collared wolves. Wolves and coyotes often hunted together and facilitated each other's kills. In a series of field studies, researchers examined the relationships between gray wolves and coyotes in Yellowstone National Park using radio-collared wolves. Wolves preyed on elk and buffalo, while coyotes preyed on moose and mule deer. In a series of field studies, researchers examined interference competition between gray wolves and coyotes in Yellowstone National Park using radio-collared wolves. Coyotes initiated the majority of encounters (85%), generally outnumbered wolves (39%), and dominated (91%) most interactions. In a series of field studies, researchers examined interference competition between gray wolves and bears in Yellowstone National Park using radio-collared wolves. Wolves initiated the majority of encounters (85%), generally outnumbered bears (39%), and dominated (91%) most interactions. In a series of field studies, researchers examined interference competition between gray wolves and coyotes in Yellowstone National Park using radio-collared wolves. Wolves initiated the majority of encounters (85%), generally outnumbered coyotes (39%), and dominated (91%) most interactions.

In a series of field studies, researchers examined interference competition between gray wolves and coyotes in Yellowstone National Park using radio-collared wolves. Wolves initiated the majority of encounters (85%), generally outnumbered coyotes (39%), and dominated (91%) most interactions.

Which of the following is true of coevolution? Coevolution is commonly found in mutualistic relationships, but it rarely functions in competitive relationships. Adaptations due to coevolution will typically magnify (reinforce) the effect of the interaction with the other species. In coevolution, adaptations are in response to another species rather than the environment. Coevolution is commonly found in mutualistic relationships, but it rarely functions in predator-prey relationships. It always produces directional selection.

In coevolution, adaptations are in response to another species rather than the environment.

All of the following are examples of diffuse coevolution with one exception. Choose the exception. Most butterflies pollinate many species of plants, and these plants are pollinated by many species of nectar-seeking insects. Squirrels and blue jays feed on acorns of many species of oaks, and these trees have evolved various survival strategies, such as the production of tannins or reproducing in small amounts followed by "mast" years in which they produce so many acorns that all seed predators are satiated. Species of birds and rodents that feed on monarch butterflies must have adaptations that allow them to avoid consuming or be able to detoxify the toxic cardenolides the monarchs sequestered as caterpillars. Tapeworms are specialized to infect multiple hosts at different stages of their lifetime. In most species of euglossine bees, a single bee species is specialized to pollinate a single species of orchid.

In most species of euglossine bees, a single bee species is specialized to pollinate a single species of orchid.

__________ species tend to have long lives and lower growth and dispersal rates. Seral Late successional Pioneer Intermediate successional Early successional

Late successional

Which of the following statements about a common trait of late successional species is true? Pioneer species are K-strategists, whereas late successional species are r-strategists. Late successional species tend to have high reproductive rates. Late successional species tend to be excellent competitors. Late successional species tend to have excellent dispersal abilities. Late successional species tend to be small and have high growth rates.

Late successional species tend to be excellent competitors.

Which of the following statements about the physical structure of communities is FALSE? Most photosynthesis in a temperate lake occurs in the hypolimnion of the lake. Light penetration influences stratification in aquatic communities. An understory will develop below the canopy if there is ample light and nutrients. The forest canopy is the site of greatest photosynthesis. Decomposition in a forest occurs mainly on the forest floor.

Most photosynthesis in a temperate lake occurs in the hypolimnion of the lake.

In looking at a distribution map you see an empty space where habitat conditions are suitable for that species. Why might that exist? Other species outcompete it in that space. The species has a limit to population growth. That species prefers other areas. The space is due to the null model.

Other species outcompete it in that space.

Which of the following statements about a common trait of pioneer species in terrestrial environments is likely to be FALSE? Pioneer species produce a large number of seeds. Seeds of pioneer species are dispersed by the wind or animals. Their seeds can survive for long periods in the seed bank. Pioneer species are shade tolerant. Pioneer species grow rapidly.

Pioneer species are shade tolerant.

__________ succession occurs in an area not previously occupied by a community. Old-field Colonization Secondary Initial Primary

Primary

Species A prefers a more dry habitat but grows in a wet habitat. Why might this be? Species A requires large amounts of moisture to grow. Species B outcompetes A in the dry habitat. Species B prefers a wet habitat. Species A's fundamental niche is restricted to a wet habitat.

Species B outcompetes A in the dry habitat.

Which of the following is an example of allelopathy? Lions and wild dogs compete for Thompson's gazelles, but lions also kill wild dogs. The California sage, Salvia, uses chemicals to inhibit the growth of competitive plants. Some genes in a caterpillar become detrimental when a new parasitoid wasp invades the habitat. The barnacle Balanus outcompetes Chthamalus everywhere except in the upper intertidal zone, where it is subjected to desiccation. Darwin's finches possess different beak depths, depending on whether they co-occur.

The California sage, Salvia, uses chemicals to inhibit the growth of competitive plants.

In seed predation, birds will often preferentially consume smaller seeds, as they are easier to digest. Seed size is a heritable trait. What happens over time? The plants will begin to produce even more small seeds to compensate for the predation. The birds switch to larger seeds to even out their consumption. The birds act as agents of natural selection, and the average seed size of the population changes. The average seed size remains the same, and the birds continue to consume only the small seeds. The plants will stop producing small seeds and will start producing larger seeds.

The birds act as agents of natural selection, and the average seed size of the population changes.

If you were to graph predator and prey populations, which of the following accurately describes the relationship between predator population size and death rate of the prey species? (Assume that there are unlimited prey.) The death rate of the prey species will be an exponential relationship with a negative slope that becomes more negative with predator population size. The death rate of the prey species will be an inverse linear relationship with a negative slope. The death rate of the prey species will be a direct linear relationship with a positive slope. The death rate of the prey species will rise exponentially initially; then it will reach an asymptote. The death rate of the prey species will be an exponential relationship with a positive slope that increases with predator population size.

The death rate of the prey species will be a direct linear relationship with a positive slope.

You find a forest with a few different tree species: maple, oak, hickory, and tulip polar. You determine that the maples are abundant in the understory, and the hickories have the largest biomass. Which of the following statements can you make about this forest? The maple is clearly the dominant species, as it is the most abundant. The hickories are clearly the only dominant species, as they have the greatest biomass. There is not a dominant species in the forest, as there is species diversity, and dominance requires a species diversity of zero with one dominant. The maples and the hickories are possible dominant species, depending on how you are analyzing the structure of the forest. The dominance of this forest is four.

The maples and the hickories are possible dominant species, depending on how you are analyzing the structure of the forest.

Which of the following statements is true? Germination rates vary among species, but these differences do not translate into differences in competitive ability. The outcome of competition can be influenced by factors other than limited resources. Plants with high growth rates under high light conditions tend to be overgrown quickly in newly opened habitat patches. Multiple species tend to perform their best under the exact same conditions. Temperature, humidity, and salinity have little effect on competition.

The outcome of competition can be influenced by factors other than limited resources.

Which of the following statements is true? Natural selection plays little role in competition among species. Two similar species in the same habitat that do not currently compete may have competed previously. Niche overlap is always related to the degree of competition for a resource. Character displacement is the convergence of characters to better exploit the same resource. Resource partitioning is only a short-term solution, and all but one species will be outcompeted.

Two similar species in the same habitat that do not currently compete may have competed previously.

Resource partitioning over a long period can result in natural selection that causes a shift in features of the species' morphology, behavior, or physiology. This is called __________. competition characters overgrowth character displacement allelopathy competitive exclusion

character displacement

Change in beak size over time in Darwin's finches is an example of fundamental niche. character displacement. competitive exclusion. environmental gradient.

character displacement.

Male euglossine bees harvest the pollen and fragrance compounds from orchids, typically a specific species, and display these in various ways. The female euglossine bee is thought to choose a mate based on the quantity and/or quality of fragrance mixtures presented. The orchids pollinated by these bees have evolved elaborate trapping mechanisms that will often only allow a single species of bee to enter and collect the fragrance; the trap will then force the bees to exit in a way that attaches the orchid's pollen to them. The elaborate courtship ritual and flower development both act to enhance reproductive success of the insect and orchid, respectively. This is an example of __________. coevolution parasitoidism parasitism competition commensalism

coevolution

An egret eats insects stirred up by grazing animals. Which of these terms applies to the relationship between the egret and the grazing animal? commensalism competition predation parasitism mutualism

commensalism

Spanish moss (Tillandsia usneoides) is native to the southeastern United States where it is often found growing on live oak trees (Quercus virginiana). Spanish moss is a flowering plant, not a true moss, and it is an epiphyte, drawing water and nutrients from the air. It does not harm the tree or extract nutrients. The relationship between Spanish moss and the live oak tree is an example of __________. commensalism ammensalism predation. competition parasitism

commensalism

A(n) __________ is a group of species that occupy an area and may interact directly or indirectly. ecosystem metapopulation population community family

community

In aquatic ecosystems, the __________ is the depth at which net primary productivity is zero because respiration equals gross primary productivity. aphotic zone balancing depth zero-growth depth thermocline compensation depth

compensation depth

Humans and sharks both eat fish. Which of these terms applies to the relationship between the human and the shark? commensalism parasitism mutualism competition predation

competition

The alpha and beta terms represent the __________ in the Lotka-Volterra models of population growth. competition coefficients population sizes energetic efficiencies intrinsic growth rates death rates

competition coefficients

The Russian biologist G. F. Gause conducted a series of laboratory experiments on the Lotka-Volterra competition model. Gause found that Paramecium aurelia outcompetes Paramecium caudatum when they are grown together in a mixed culture. This is the classic example of __________. competitively cyclic populations resource partitioning a competitively unstable equilibrium competitive exclusion competitive coexistence

competitive exclusion

In aquatic environments, the three major environmental gradients of water that directly influence the distribution and dynamics of communities include temperature, depth, and oxygen content. pressure, temperature, and depth. depth, flow rate, and salinity. flow rate, salinity, and oxygen content.

depth, flow rate, and salinity.

An earthworm that feeds on the remains of plants and animals is acting as a _____ producer secondary consumer detritivore primary consumer tertiary consumer

detritivore

Relative abundance is calculated by __________. dividing the total number of individuals of all species present in the community by the total number of individuals of the species of interest multiplying the species richness by the species evenness dividing the total number of each of the species in the community by the total number of individuals of all species and then adding each of these numbers together for a single value for the whole community dividing the total number of individuals of the species of interest by the total number of individuals of all species present in the community multiplying the total number of individuals of all species in a community by the total number of individuals of a given species

dividing the total number of individuals of the species of interest by the total number of individuals of all species present in the community

The range of physical and chemical conditions under which a species can persist (survive and reproduce) and the array of essential resources it utilizes constitute the species' __________. ideal environment habitat range of tolerance living space ecological niche

ecological niche

According to the first law of thermodynamics, potential energy tends to degrade into an unavailable form. chemical reactions are exothermic. energy is neither created nor destroyed. entropy tends to increase.

energy is neither created nor destroyed.

Evapotranspiration shows a positive relationship with aboveground net primary productivity. This is because __________. evapotranspiration is another way of measuring precipitation, and precipitation provides the moisture plants need to grow. evapotranspiration is the term for CO2 absorption by leaves, and plants need CO2 to create the products of photosynthesis evapotranspiration is negatively correlated with the number of open stomata evapotranspiration is positively correlated with the number of open stomata, and open stomata allow the plant to take in more CO2 evapotranspiration is the amount of water that must be exchanged for CO2

evapotranspiration is positively correlated with the number of open stomata, and open stomata allow the plant to take in more CO2

The __________ is the full range of conditions and resources that a species can exploit when free from interference by other species. competitive niche basic niche fundamental niche realized niche actual niche

fundamental niche

The biological structure of a community is first constrained by the __________ of the species. realized niches direct interactions trophic interactions fundamental niches competitive interactions

fundamental niches

Which of the following shows the proper sequence of vegetative succession for most sand dunes? grasses, shrubs, pine trees, oak trees oak trees, pine trees, shrubs, grasses grasses, oak trees, shrubs, pine trees grasses, pine trees, shrubs, oak trees pine trees, oak trees, grasses, shrubs

grasses, shrubs, pine trees, oak trees

In a rank-abundance curve comparing two communities, the community with the greater species richness is characterized by a greater length of the curve and a steeper slope. greater length of the curve and a more gradual slope. lesser length of the curve and a steeper slope. lesser length of the curve and a more gradual slope.

greater length of the curve and a more gradual slope.

Detrital food chains contain all of the following except carnivores. herbivores. decomposer herbivores. detritus.

herbivores.

As an example of an indirect interaction, a predator may __________ the population density of one or more inferior competitors by __________ the abundance of the superior competitor, which is the predator's main prey. indirectly reduce, directly reducing increase, reducing directly increase, indirectly reducing Not affect, indirectly reducing. reduce, increasing

increase, reducing

In a rocky intertidal community where starfish are absent, mussels outcompete all other species. However, when starfish are present, they reduce mussel populations, and other invertebrates, including some that are not eaten by starfish, are able to persist in the community. The interaction between the starfish and the other invertebrates that they do not consume is an example of __________. a bottom-up effect apparent competition. indirect commensalism indirect mutualism intraguild predation

indirect commensalism

When sea otters are removed from kelp communities of the northeastern Pacific Ocean, the kelp are quickly overgrazed by sea urchins, which are a favorite food of otters. Thus, the entire community structure changes. This is an example of __________. succession keystone predation the intermediate disturbance hypothesis intraguild predation apparent competition

keystone predation

During plant succession, animals can __________. remain viable despite habitat modification due to vegetation change lose their habitat due to vegetation change increase in species richness and diversity through time, starting with low diversity in the earliest stages of succession and decline as succession proceeds easily respond to changes in plant structure, but are forced out by changes in plant species composition modify their habitat requirements to match vegetation change

lose their habitat due to vegetation change

What might be a result of hunting sea otters to extinction for their fur? loss of barnacles loss of killer whales loss of kelp beds loss of sea urchins

loss of kelp beds

In most plant-pollinator interactions, plants species are pollinated by multiple animal species, and each animal species pollinates multiple plant species. multiple animal species, and each animal species pollinates one plant species. one animal species, and each animal species pollinates multiple plant species. one animal species, and each animal species pollinates one plant species.

multiple animal species, and each animal species pollinates multiple plant species.

Humans who have pets tend to be healthier than humans who do not have pets. Which of these terms applies to the relationship between a human and a pet? competition commensalism parasitism mutualism predation

mutualism

Oxpeckers are birds native to Africa. They have been observed feeding on ticks on the backs of large mammals and were thought to reduce the number of ticks. Recent studies indicate that the tick load is unaffected by the oxpeckers, and the oxpeckers actually reopen old tick wounds and consume the mammals' blood. Ecologists are considering reclassifying the relationship between oxpeckers and large African mammals from __________ to __________. mutualism; parasitism parasitism; mutualism mutualism; predation predation; parasitism commensalism; ammensalism

mutualism; parasitism

Which of these terms applies to the relationship between a dog and a blood-sucking tick? predation mutualism parasitism competition commensalism

parasitism

How is energy transferred from one trophic level to the next? Select all that apply. (Fig 3) cellular respiration parasitism herbivory heat loss predation

parasitism herbivory predation

In marine habitats, photosynthesis is limited to the __________ zone. Most decomposition occurs in the __________ zone. photic, benthic photic, aphotic photic, photic aphotic, photic aphotic, benthic

photic, benthic

What does the following formula represent? dN1/dt = r1N1(1 - (N1 + N2)/K1) population growth of species 1 in presence of species 2 population size in the presence of species 2 carrying capacity of species 1 in absence of species 2 population growth of species 1 in absence of species 2

population growth of species 1 in presence of species 2

A human eats a deer. Which of these terms applies to the relationship between the human and the deer? predation commensalism mutualism parasitism competition

predation

A cow eating grass is an example of a _____. detritivore secondary consumer tertiary consumer producer primary consumer

primary consumer

A volcanic island in the middle of the Pacific Ocean explodes, and all life is removed from the island. However, decades later, the island has a covering of plant life, and some animals have appeared. This is an example of __________. assimilation secondary succession old-field succession bog succession primary succession

primary succession

In an ecosystem, phytoplankton are _____. secondary consumers detritivores tertiary consumers producers primary consumers

producers

One effect of decreasing wolf populations in North America is increased bear populations. decreased deer populations. range retraction for elk. range expansion for coyotes.

range expansion for coyotes.

The __________ describes the range of conditions and resources that a species exploits as a result of interactions with other species. basic niche fundamental niche competitive niche realized niche actual niche

realized niche

The __________ is the portion of the species' niche that the species actually occupies when biotic interactions are taken into consideration. realized niche generalized niche specialized niche environmental niche fundamental niche

realized niche

When a human eats a steak, the human is acting as a _____. producer tertiary consumer detritivore primary consumer secondary consumer

secondary consumer

Old-field succession includes a series of communities transitioning from grasses and forbs to shrubs to trees. Each of these communities along the successional continuum is called a __________. successional state temporal community seral stage successional stage sere

seral stage

The directional change in community structure through time is called __________. cessation a sere serial change succession modification

succession

Seasonal and yearly variations in __________ directly influence primary production. temperature competition for solar input wind patterns temperature and precipitation precipitation

temperature and precipitation

A human who just ate a hamburger is eaten by a shark while swimming. The shark is acting as a _____. producer secondary consumer primary consumer tertiary consumer detritivore

tertiary consumer

In the Lotka-Volterra equations, the competition coefficients represent __________. the per capita effect that an individual of one species has on another species the per capita effect of an individual of one species on members of its own species the effect that a competing species has on another species, raising the effective carrying capacity the total effect that an individual of one species has on another species the total effect of an individual of one species on members of its own species

the per capita effect that an individual of one species has on another species

Two bird species compete in the forest for the same seeds. If α = 0.75 and β = 0.25, then (assuming the same carrying capacity for both) species 2 "wins" and will outcompete species 1. the rate of seed consumption is the same for both species. species 1 "wins" and will outcompete species 2. the species coexist.

the species coexist.

Rank abundance is __________. the number of different species the community ranking based on species evenness, ranked from the most to the least abundant the species ranking based on relative abundance, ranked from the least to the most abundant the community ranking based on species evenness, ranked from the least to the most abundant the species ranking based on relative abundance, ranked from the most to the least abundant

the species ranking based on relative abundance, ranked from the most to the least abundant

In a food web, organisms can be grouped based on how they obtain their energy. These groupings are called __________. feeding stages functional groups trophic levels web groups guilds

trophic levels