Ecology Ch. 14

What term is used to describe an organism that will kill and consume other organisms? Predator

Which of the following example is considered an exploitative interaction? A cat killing a sparrow

Which of the following are generalist predators on the snowshoe hare? Coyote, red foxes

Identify the correct sequence for the life cycle of Adelina, beginning with entering the host and ending with being encased in oocysts. Oocysts of Adelina enter the host; Oocysts develop into the sporozoite stage; Sporozoites enter the host’s haemocoel; Sporozoites become merozoites and invade host cells; Zygotes give rise to sporozoites that are encased in oocysts

Within the Lotka-Volterra model, what limits the host population size? Amount of predators

Identify the trophic levels that influence the population cycle of the snowshoe hare. The hares’ food source; the hares; the predators of the hares

What term is used to describe an organism that lives on the tissues of another, without killing it? Parasite

When Adelina was present, Tribolium castaneum was more successful. FALSE

Which group of organisms are the dominant herbivore in a forest ecosystem? Arthropods

Which variables are used to calculate the predator’s combined response to increased prey density? The number of predators per area; prey consumed by each predator

Within the Lotka-Volterra predator-prey equation, what symbol is used to represent the number of prey killed by predators? The symbol p

A prey defensive strategy called predator satiation occurs when prey are present in a very high density, thus decreasing an individual’s chances of being killed by a predator

Which statement is correct about the numerical response of both coyotes and lynxes in response to the increase in the hare population? Both the coyote and lynx populations increased in numbers in response to an increase in the hare population

Which of the following prey populations would be impacted by the red fox population? Roe deer; Grouse; Mountain hares

According to the predator influence on prey population hypothesis, what will ultimately happen to the prey? Their population will decrease

What role do refuges play in regards to exploited populations? Protection against predators and parasites

The population cycle in the snowshoe hare population is determined strictly by the number of predators in the community. FALSE

Which of the following relationships are considered exploitative interactions? Parasite/host; predator/prey

Which prey species was used by Gause during his first attempt to reproduce the Lotka-Volterra population cycles? Paramecium caudatum

What terms is used to describe an organism whose larva kills the host and consumes it? Parasitoid

Which organisms are often classified as pathogens? Mosquitos; flies; ticks

What defensive mechanisms will plants produce in response to being preyed upon by snowshoe hares? Elevated concentrations of plant defensive chemicals

According to the researchers’ calculations, there were five fewer caterpillars damaging cotton plants when Brazilian free-tailed bats are feeding on the bollworm moths

Which population benefits from the presence of a refuge? Prey

Which variables influenced the outcome of competition between Tribolium castaneum and T. confusum? Moisture; temperature

Ecologists studying temporal dynamics will study the interactions between predators and prey

What happened to the hare population as a result of the decrease in the red fox population? Increase by two to four times

Within the Lotka-Volterra equation, what opposes the growth rate of the predator population? The number of predator deaths

The predator’s combined response to increased prey density is measured as the prey consumed per unit area

Which features of group life make it a refuge? Living in a large group decreases an individuals chances of being the one killed; a large group can scare away a predator

Which factor(s) has the greatest influence on the snowshoe hare population? The size of the predator population and the amount of food available for the snowshoe hare population

Which of the following components were required in order for Gause to produce Lotka-Volterra type predator-prey oscillations under laboratory conditions? A reservoir for the predator population; a refuge for the prey; periodic immigration of predators

Which species were used by Utida during his experimental attempt to reproduce the Lotka Volterra predator-prey cycles? Parasitoid wasps; adzuki bean weevils

Which statement is correct about the functional response of coyotes and lynx to the increase in the hare population? Coyotes killed more hares while the hare population was increasing

How long after snowshoe hares browse on plants will the plant continue to produce chemical defenses? 2 years

Temporal dynamics are studied over a period of days to decades

What percentage of the benthic biomass do the larval Helicopsyche make up in the Lamberti and Resh study? 25

Within the Lotka-Volterra model, what type of growth is assumed for the host population? Exponential

Which animals did Alfred Lotka use to model predator-prey interactions? Butterflies, moth

In the absence of a refuge, what will ultimately happen to the predator and prey populations? Extinction of both predator and prey populations

What role do conifers play in the life of a snowshoe hare? Provide cover; provide a food source

Identify the predators that play the greatest role in influencing the snowshoe hare population. Coyote; lynx

What is the immediate consequence of an increase in the snowshoe hare population? The quantity and quality of their food decreases

Identify the impact that mange mites can have upon a population of red foxes. Results in the death of the red fox; cause skin deterioration; results in hair loss

The value of p will decrease if an environment experiences an increase in the number of refuges over a period of time

When Puccinia infects the rosettes of Arabis, what group of tissues are infected? Meristematic

Which abiotic factor has the least influence on the outcome of competition between Tribolium castaneum and T. confusum? Soil texture

Which demographic of snowshoe hares are coyotes the most important predator of? Adult hares

What was the ultimate consequence of mange mites on the red fox population? They decreased the population by over 70%

What term best describes the feeding role of larval Helicopsyche? Omnivore

Identify the correct sequence of events that would occur, according to the Lotka-Volterra equation. Predator population increases, host population decreases, predator population decreases

In which way would a parasite alter the behavior of its host? It will cause the host to help increase the transmission of the parasites

Which of the following features describes an infected Arabis? Rosettes posses a high density of leaves along their length; the tip of the rosettes have a cluster of bright yellow leaves; rosettes are elongated

What relationship exists between the prey density and the percentage of prey consumed when all three predators are present? When prey density is high, the percentage of prey consumed is low

After week 3, what is the relationship between the caddisfly population and the algal biomass? As the caddisfly population increases the algal biomass decreases

Which of the following are unrealistic assumptions of the Lotka-Volterra equation? The predator populations are not subject to carrying capacities; eternal oscillations on a narrowly defined path will exist; changes in the predator population will be instantaneously translated into responses in the prey population

Mathematical models offer population biologists an opportunity to manipulate variables that cannot be controlled in the field. TRUE

What was the arthropod density on plants that were visited by bats but not by birds? 65% higher than control plants

Which month showed the largest levels of both predatory mite and prey mite populations? December

What is the first stage in the life cycle of Arabis species? Forming a rosette

If the density of prey in a given area were to increase, what would we expect to happen to the percentage of prey consumed? It would decrease

Which of the following refugees enabled the cactus Opuntia stricta to avoid predation by herbivorous insects and pathogenic microbes? Growing between 600 and 900 meters in elevation; nutrient poor soils; small isolated populations

During which stages of the weevils’ life cycle are they parasitized by the hymenopteran wasp? Pupae; larvae

At what point of the study did the caddisfly population reach its peak? Week 3

Which prey density produced the highest percentage of prey consumed? Medium

Identify the relationship, discovered by Huffaker, between predator and prey populations of mites. If the prey population increases, shortly after, the predator population will increase

According to the Lotka-Volterra equation, what is the initial response to an increase in the predator population? A decrease in the host population

What is the relationship between the prey density and the percentage of prey consumed? The higher the prey density, the lower the percentage of prey consumed

Which parasitism relationship between the wasp larvae and weevil larvae is accurate? Larvae wasp and larvae weevil

Identify the food preferences for larval Helicopsyche. Algae, bacteria

Parasites will often use the host in order to increase the parasites’ reproductive potential. TRUE

Which population did Charles Elton hypothesize was directly impacted by the intensity of solar radiation? Hares

What was the key to understanding the controls on the snowshoe hare population numbers? Studying all three trophic levels simultaneously

In the Park study, which organisms had the highest rate of cannibalism? T. castaneum

What are the consequences of the prey populations in most Lotka-Volterra experiments? The prey populations goes extinct

What were the consequences of reintroducing wolves into Yellowstone National Park? The elk herd altered its pattern of distribution

Which of the following are unrealistic assumptions of the Lotka-Volterra equation? Changes in the predator population will be instantaneously translated into responses in the prey population; eternal oscillations on a narrowly defined path will exist; the predator populations are not subject to carrying capacities

What is the correct order of events in the life cycle of the adzuki bean weevil? Eggs hatch into larvae that metamorphose into pupae that develop into adult weevils

Which organism was the intermediate host species in Janice Moore’s study? A terrestrial isopod

According to Lotka the value of p should remain the same across different environments. FALSE

In what way does Plagiorhynchus alter the behavior of Armadillidium? Armadillidium will increase the amount of time they spend in the open

The Lotka-Volterra equation is realistic in assuming that the predator and prey populations will be able to oscillate continuously without interruption. FALSE

Identify the amphipod behavior that will occur when they are parasitized by spiny-headed worms. Positive phototaxis

What happened to the hare population when the Krebs research team excluded predators and added food to the study plot? The hare population increased by 11 times

What is the insect consumption level of a lactating Brazilian free-tailed bat? Two-thirds its body weight

Which reason best explains why most attempts to produce Lotka-Volterra type oscillations in laboratory populations have failed? The predator population has gone extinct in a fairly short period of time

In order to understand the dynamics of the snowshoe hare population, how many trophic levels were necessary to be studied? Three

What type of ecological relationship did Janice Moore study? Parasite-host

What is the ultimate consequence of the behavioral change that Plagiohynchus will inflict upon Armadillidium? Armadillidium will be preyed upon more frequently by birds

Which factor would most likely cause p to differ between two environments? A difference in the availability of refuges

Why did the elk in Yellowstone National Park change their behavior? They were afraid of the increased wolf population in the park

What happened to the hare population when the Krebs research team reduced the predators on the study plot? The hare density doubled

Which insect group makes up the majority of the diet of a lactating Brazilian free-tailed bat? Moths

Which population did Charles Elton hypothesize was directly impacted by the intensity of solar radiation? Hares

Recognize the benefit that positive phototaxis provides to spiny-headed worms. Greater chance of being transmitted to another host

Ecology Ch. 13

In order for an allopolyploid species to become fertile (capable of sexual reproduction), it must first double its chromosome number

Which of the following are considered to be characteristics of models used in ecological research? Artificial, insightful, abstraction

In Parks’ competition experiments with flour beetle, the outcome of competition was dependent upon the environmental conditions. Match the conditions to the outcomes.

Hot and wet >> T.castaneum usually dominates

Cool and dry >> T. confusum usually dominates

In between >> either species could win

Which of the following factors in Brown’s experiments with desert rats help to provide strong evidence of competition? Large spatial scale, long time scale, well replicated

In the Lotka-Volterra equations, the competition coefficient measures the effects of an individual of species 2 on species 1

Interference competition involves the direct interaction between individuals

Under self-thinning, plant populations become less dense as they grow older

The study of competition has gone through several phases. Rank the following in order from first to most recent. Theory, laboratory models, experimentation, re-evaluation

Competition is an important factor in the spread of invasive species

“Scramble competition” where individuals “race” to consume a limiting resource can be considered to be a synonym for exploitative competition

The Lotka-Volterra model assumes that resources will diminish as a result of both intra- and interspecific competition

When the Paramecium were grown separately, the change in carrying capacity in response to a change in food supply is evidence of interspecific competition. FALSE

In the results for their experiments with planthoppers, Dennon and Roderick found that insects grown in the highest density cages were characterized by which of the following? Reduced survivorship, decrease body length, increased development time

In the Lotka-Volterra model, when the zero growth isoclines for both species do not cross, which of the following outcomes could you expect? Only species 2 wins, only species 1 wins

When the two species were grown together, the extinction of one of the species is evidence of the competitive exclusion principle

In the Lotka-Volterra equations, when the value of the competition coefficient is greater than 1, then we can think of intraspecific competition being less than interspecific competition

An important condition of Gause’s experiments with Paramecium species was that resources were limiting

Along coastal locations with greater fetch, you would expect S. anglica to be found to be found at a higher elevation in the intertidal zone as compared to more sheltered locations

Competition between members of the same population is considered to be intraspecific competition

Overall, re-analysis of competition research has found that the importance of competition can vary among environments and organisms

The results of mathematical models in ecology can be used to generate hypotheses for experimental research

When grown separately, the carrying capacity for each Paramecium species decreased when the bacterial food supply was reduced

The local distribution of S. anglica is determined by inundation by tides and waves

Interference competition involves direct interaction between individuals

When the two species of Paramecium were grown together, reducing the food supply resulted in decreasing the time taken for one of the species to go to extinction

Being better at consuming a limiting resource than your competitor is considered to be exploitative competition

When a population is greater than its isocline of zero population growth, one would expect the population to decrease over time

In Gause’s competition experiments with Paramecium species, he was interested in finding out whether one species would drive the other to extinction

A scientist doing research on competition between crows and vultures would be studying interspecific competition

Character displacement is more likely to occur when two species are sympatric

The difference between the two self thinning rules is that the “-1/2 rule” uses total plant biomass while the “-3/2 rule” uses average plant biomass

How did Brown restrict the movement of rodents into and out of the study plots? Fencing

In the “-1/2 self-thinning relationship” we would expect the plant biomass would increase as plant density decreases

In Tillman’s experiments with grass, plants grown at higher densities had lower biomass per plant than those grown at lower densities

Self-thinning is the result of intraspecific competition

One of the six criteria for character displacement to occur is that the observed differences between sympatric and allopatric populations must have a genetic basis

The beak sizes of Darwin’s finches are related to differences in diet

When the two species of Galium were grown in acidic soils, both species grew slower than when they were grown in more basic soil

Experiments by other researchers have repeated the results of Brown’s competition experiments

The invasive marine snail Batillaria arrived in California as an “accidental tourist” associated with the introduction of oysters from Japan

The “priority effect” in competition occurs when the species that establishes itself in greater numbers first, wins. TRUE

Grosholz, in his competition experiments, found that isopods grown at higher density had reduced survivorship compared to those grown at lower densities

Byers was able to demonstrate the potential for resource competition because diatom (algae) cover decreased when both species were present at high densities

From the perspective of interspecific competition, we would expect that under the competitive exclusion principle, species living together will generally have different niches

In his experiments with barnacles, Connell looked at the effects of competition on Chthamalus by periodically scraping off Balanus that settled on the rocks

The expected changes in the populations of the small granivores was a result of competition with large granivores

In his experiments on competition between several species of desert rodents, Brown grouped the species based upon size and feeding habits

In the second set of experiments with the snails Cerithidea and Batillaria, Byers found that the growth rate of Batillaria was greater than that of Cerithidea at all densities

At the end of Tourney’s experiments, the amount of vegetation growing on the ground in the control plots was less than the amount in the trenched plots

The Lotka-Volterra model predicts that coexistence occurs when intraspecific competition is stronger than interspecific competition

When Tansely grew the two Galium species together, one species dominated in its native soil type

In the “-3/2 self-thinning rule” we would expect individual plant biomass to decrease as plant density increases

Brown hypothesized that small holes in the fencing would lead to increases in the populations of small granivorous rodents and no change in the populations of small insectivorous species

Grosholz proposed that the effects of competition between isopods was the result of increased cannibalism

The competitive exclusion principle states that two species with identical niches cannot coexist indefinitely

One of the six criteria for character displacement to occur is that differences between pairs of sympatric species must be greater than differences between allopatric populations of the same species

The purpose of Byers’ first experiments with the snails Cerithidea and Batillaria was to determine the effects of the snails density on their food supply

The purpose of Byers’ second experiments with the snails Cerithidea and Battillaria was to determine the effects of snails’ density on the growth rates of the two species

In self-thinning the “thinning” refers to a decrease in population density

Granivores are organisms that feed on seeds

The results of Brown’s experiments were consistent with his hypothesis because the populations of small granivores increased when Dipodomys was excluded

The spread of Btillaria from its initial colonization site has been limited due to lack of planktonic larvae

The “priority effect” in competition occurs when the species that starts with greater numbers wins

In Tourney’s experiments investigating competition, the purpose of trenching around the perimeter of plots was to eliminate potential root competition

In the “-1/2 self-thinning relationship” the “-1/2” refers to the slope of the line when plotting the log of the plant biomass against log of plant density

In re-analyzing earlier research on competition, Shoener’s and Connell’s research produced differing conclusions about the importance of competition in nature

As a C4 plant, one would expect S. anglica to photosynthesize better in warmer environments

The environmental conditions in which one of the Galium species dominates, when they are grown together, is considered that species’ realized niche

In general, Gurevitch found that larger experiments of longer durations had less variable results than those of smaller studies and shorter durations

Character displacement in a sympatric demonstrates the evolutionary outcomes of ecological interactions

As part of his research on the invasive snail Batillaria, Byers was able to demonstrate its competitive dominance to Cerithidea by using research plots that contained both species. FALSE

The environmental conditions in which Chthamalus grows, when Balanus is allowed to persist, can be considered its realized niche

The environmental conditions in which the Tribolium beetles could grow without other competitors can be considered their fundamental niches

One possible explanation for S. anglica having a lower upper limit to distribution at higher latitudes is competition with C3 grasses

The environmental conditions in which the Galium species could grow when grown separately can be considered their fundamental niches

The difference in results between Connell’s and Schoener’s re-analysis of competition experiments was that they used different studies and different criteria for analysis

G. fortis have larger beaks when they are sympatric to G. fulginosa in the Galapagos Islands. This characteristic displacement in beak size would suggest that the species has different feeding niches between these locations

In a re-analysis of competition studies, Gurevitch found that there were differences between studies based upon organisms and methods

The environmental conditions in which one of the Tribolium beetles dominates when grown together is considered that species’ realized niche