Nres 219 quiz test 2

1. In some worm species, the actions of individual worms make the surrounding soil more hospitable to member of the same species. Such a phenomenon would tend to encourage which dispersion pattern? ? ?? regular clumped random metapopulation semelparous

... clumped

A plant that produces an extensive root system in order to efficiently obtain nutrients from the soil (even when those nutrients are in short supply) would most likely be found in which of Grime's categories of plants?

... competitive

1. Which of the following statements is false? ? ?? The distribution of a species is the geographic area where individuals of that species are present.? Population abundances change over time and space. A population may consist of a series of patches of individuals that are isolated in space but are connected by dispersal and interbreeding. Most organisms have similar capacities for dispersal. The average population density is the number of individuals in a population divided by the spatial area that the population occupies.

...Most organisms have similar capacities for dispersal.

1. A unicellular sexually reproducing ciliate has seven different mating types that each produce gametes of the same size. Any gamete from any mating type can fuse with any other gamete except for one of its own mating type. These ciliates exhibit: (choose one) anisogamy isogamy monogamy allometry phenotypic plasticity

...isogamy

1. In a metapopulation setting, habitat fragmentation will generally cause __________ to increase and __________ to decrease. (Select the option below that best addresses both blanks.)? the colonization rate; the extinction rate the colonization rate; environmental stochasticity the extinction rate; the colonization rate the extinction rate; genetic drift genetic drift; the extinction rate

...the extinction rate; the colonization rate

1. Two species of plant, Lespedeza cuneata?and Lespedeza virginica?are engaged in resource competition according to the Lotka-Volterra equation. If each?L. cuneata?plant decreases its own population growth rate by 0.02 per year, but each L. virgnica?plant reduces the growth rate of the L. cuneata?population by 0.005 per year, then what is the competition coefficient that expresses L. virginica's effect on L. cuneata? 0.005 0.02 0.25 0.4 4

0.25

1. All exploitative relationships have the potential to reduce the __________ of food organisms. survival growth reproduction All of the above None of the above

All of the above

1. Which of the following statements about logistic population growth is true? ? ?? The carrying capacity is the maximum population size that can be supported by the environment indefinitely. At low densities, logistic growth is similar to exponential growth.? If a population is at the carrying capacity, there is no population growth according to the logistic model. All of the above. None of the above. ? ??

All of the above

1. Which of the following organisms cannot?mount immune responses to parasites? mammals birds insects? plants All of the above can mount immune responses.

All of the above can mount immune responses

1. Three different populations of beetles all have the same overall density over their ranges, but they have different patterns of dispersion. Population A has a regular dispersion pattern; Population B has a random dispersion pattern; and Population C has a clumped dispersion pattern. The population that is most likely to suffer from the effects of overcrowding is Population ______, and the population that is least likely to suffer from overcrowding is Population ______. (Select the answer that best fits both blanks.) A; C A; B C; B? C; A B; A

C; A

1. Two species of birds feed on berries. The birds are active at different times of the day, and they do not come into contact with one another. Nonetheless, the presence of one species limits the survival and reproduction of the other. What type of competition is this? Interference Exploitative Allelopathic Logistic This is not an example of competition. ? ??

Exploitative

1. Which of the following is an advantage that endoparasites have over ectoparasites? Greater dispersal ability. Greater ease of feeding. Less susceptible to the host's immune system. Greater ability to overcome host defenses, due to its large size relative to that of the host. Broader range of suitable host species.

Greater ease of feeding

1. In which of the following ways does the Lotka-Volterra predator-prey model of population growth differ from the logistic model? In the Lotka-Volterra model, predator population growth does not depend on the availability of the predator's resources. In the Lotka-Volterra model, prey do not experience density-dependent population regulation. Analysis of the logistic model uses zero population growth isoclines, but these cannot be used in the Lotka-Volterra model. The logistic model generates characteristic population cycles, while the Lotka-Volterra model results in stable population sizes at carrying capacity. The death rate of predators in the Lotka-Volterra model depends entirely on the abundance of prey items.

In the Lotka-Volterra model, prey do not experience density-dependent population regulation.

1. Which of the following features would is most likely to be exhibited by an organism that is an "r-strategist"? It takes a long time to reach sexual maturity. It reproduces well under very crowded conditions. It has a high population growth rate. It shows an alternation of generations. It is diploid.

It has a high population growth rate.

1. In the famous experiment by Paine, removal of the sea star predator Pisaster?reduced the species diversity of its prey items until only a single prey species was left. These results best illustrate which of the following principles? Predators and prey sometimes coevolve together. Predators can decrease the abundance of a dominant competitor, leading to persistence and coexistence of inferior competitor species. Prey experience trade-offs between predator avoidance and survivorship. Prey experience trade-offs between avoidance and fecundity. Predators generally behave as optimal foragers.

Predators can decrease the abundance of a dominant competitor, leading to persistence and coexistence of inferior competitor species.

1. For your undergraduate research project, you decide to conduct an experiment similar to that of Huffaker, using an herbivorous mite and a predatory mite that is very good at capturing and consuming the herbivorous one. You set up a very simple habitat in the lab, and you introduce both mite species to this habitat. What is the most likely outcome of this experiment? Prey and predator populations will both increase for a while, but they will soon crash and go extinct. The prey will go extinct, but the predator will persist. The predator will go extinct, but the prey will persist. Both predator and prey will persist at very high, stable population sizes. The predator and prey populations will persist and exhibit population cycles.

Prey and predator populations will both increase for a while, but they will soon crash and go extinct

1. Tribbles reproduce in synchrony at regular intervals. When the logarithm the tribble population on the star ship Enterprise is plotted against time, the series of points follow a straight and increasing line. Which of the following statements is true? The tribble population is increasing in size geometrically. The?? of this tribble population is constant and less than 1. The tribbles are experiencing density dependent population regulation. The tribble population is near its carrying capacity. This kind of population growth can only happen for species with a Type II survivorship curve.

The tribble population is increasing in size geometrically.

1. By pitting two species of worms against each other at varying densities, researchers have determined that the zero growth isocline of species A is always above that of species B. This means that Worm A will always exclude worm B. Worm ?B will always exclude worm A.? One of the worm species will exclude the other one, but either A or B might win, depending on the initial conditions. The two worm species will coexist at higher population densities than either would have alone. The two species should coexist, but worm A will have a higher population density than worm B.

Worm A should always exclude worm B.

1. The Australian palm Calamus australis?has evolved a tolerance to the loss of sunlight that occurs when lichens grow on it. This is an example of a mutualism evolving into a commensalism. a commensalism evolving into a mutualism. a host-parasite relationship evolving into a commensalism. coevolution. a mycorrhiza.

a host-parasite relationship evolving into a commensalism.

1. A bacterium that can only live inside of an aphid must be: a parasite. a parasitoid. a symbiont. an endoparasite. a plasmodium.

a symbiont

1. Many species of butterflies are noxious to predators. They also have bright red coloration that indicates to potential predators that they are unpleasant or even harmful to eat. This is an example of __________ coloration. exploitative cryptic apomatic aposematic induced

aposematic

1. Lions running on grass do not benefit from this interaction, but their activity helps the grass grow. This is an example of mutualism. endosymbiosis. commensalism. ectoparasitism. ammensalism.

commensalism

1. Suppose that a bee and a flowering plant are engaged in an ecological relationship in which only the bee benefits, but the plant is not harmed. This relationship is a __________, and it is __________ for the flower. (Select the answer that best fills in both?blanks.) commensalism; facultative commensalism; either facultative or obligate mutualism; facultative mutualism; either facultative or obligate mutualism; obligate

commensalism; facultative

1. The total area of productive ecosystems required to support a particular individual or population is known as its ? ?? carrying capacity. ecological footprint. logistic growth curve. survivorship curve. density dependent factor.

ecological footprint.

1. For an ecological interaction to be a mutualism, the net benefits must exceed the net costs for both partners. exceed the net costs for one partner, but not necessarily the other one. be less than the net costs for both partners. be less than the net costs for one partner, but not necessarily the other one. be constant through time.

exceed the net costs for both partners.

1. Mutualisms and commensalisms are also called amelioration. conciliation.? benefactory. facilitation. symbiosis. ? ??

facilitation

1. An evolutionary ecologist is interested in studying evolutionary change over the course of many years in a population of lizards that often reproduce asexually via parthenogenesis. Which type of individual would be the most appropriate focus of the study. ? ?? genet ramet sporophyte ruderal senescent

genet

1. Compare exponential population growth and geometric population growth. Which of the following statements is true? ? can be calculated from r, and it is equivalent to the natural logarithm of r. ? can be calculated from?r, and it is equivalent to e raised to the power of?r. ? is used in the equation for exponential growth curves. Populations with?? = 0 or r = 1 are stable, neither growing nor shrinking. If a population has a stable age structure, then it must also have ? = 1.

lambda can be calculated from r, and it is equivalent to e raised to the power of r.

1. Suppose that two species of Darwin's finches live on the same island and eat seeds, but one species eats larger seeds than the other one does. Based on this observation, we can conclude that these species are engaged in competitive exclusion. allelopathy. interference competition. resource partitioning. character displacement.

resource partitioning.

1. A species of turtle grows for several years before becoming sexually mature. It mates once, reproduces, and then dies soon afterward. This species of turtle would best be described as autotrophic endothermic iteroparous semelparous ruderal

semelparous

1. According to the basic host-pathogen model, if the combined death and recovery rate from a disease doubles, but the effectiveness of the disease spread also doubles, then the threshold density should decrease by a factor of four. decrease by half. stay the same. double. quadruple.

stay the same

1. The hairworm is an example of an "enslaver parasite." It grows inside the body of a male cricket. Eventually the hairworm takes control of the cricket, forcing it to jump into some water and drown. At this point the hairworm emerges from the cricket's body, and the parasite seeks out a new aquatic host to complete the next phase of its life cycle. What advantage does the cricket get when it goes to the water? By hydrating the cricket, the water decreases the negative effects of the parasite. Female crickets live near water, so the infected cricket has an increased chance of mating before the parasite kills him. There is no advantage to the cricket. This behavior only benefits the parasite. There is no advantage to the cricket, but by drowning in the water, the cricket reduces the prevalence of parasitism in the species. The water helps the cricket get rid of the parasite.

there is no advantage to the cricket. This behavior only benefits the parasite.

1. A bacterium living in the gut of an aphid produces essential amino acids for the aphid, which in turn provides sugar to the bacterium. Assuming that each partner is benefiting from the interaction, this would be an example of which kind of mutualism? trophic metabolic service chemical None of the above; this is not a mutualism.

trophic

1. Which of the following cannot be a resource that might be basis for competition? oxygen physical space? light water velocity All of the above are resources.

water velocity

1. A population of plants has a current size of 150 individuals. If ? (lambda) is 1.2, then what is the expected population size after two generations? 144 180 200 216 288

216

1. Which of the following statements about mutualisms is true? Partners join mutualisms for altruistic reasons. Mutualisms often impose costs on the partners. Conflicts of interest seldom exist in mutualisms. All mutualisms are also symbioses. All mutualisms are obligate for both partners.

Mutualisms often impose costs on the partners.

1. Which of the following statements about mycorrhizae is true? Although mycorrhizae are very common in angiosperms, most gymnosperms do not form these associations. Mycorrhizae are symbiotic associations between plant roots and fungi. Mycorrhizae are typically commensalisms, not true mutualisms, because only the plant benefits. Plants with ectomycorrhizae face a trade-off, because the presence of the fungus increases the susceptibility of plant roots to attack by pathogenic bacteria. Mycorrhizae should be most beneficial for plants living under nutrient-rich conditions, and they should be less helpful when nutrients are hard to obtain.

Mycorrhizae are symbiotic associations between plant roots and fungi.

1. You have been monitoring three different populations of butterflies that are each acting like separate metapopulations. According to your studies, you estimate that Population A has a patch colonization rate of 0.06 and a patch extinction rate of 0.12;?Population B has a patch colonization rate of 0.04 and a patch extinction rate of 0.02;?Population A has a patch colonization rate of 0.10 and a patch extinction rate of 0.14. According to Levin's metapopulation model, which of these populations would be expected to persist for a long time? Population A only Population B only Population C only Both Population A and Population B? None of them ought to persist for a long time.

Population B only

1. Which of the following statements about symbiosis are true? All symbioses are mutualisms. All symbioses are either mutualisms or commensalisms. All mutualisms are symbioses. All symbioses are obligate relationships for both partners. Symbioses can sometimes help the host species, sometimes harm the host, and sometimes neither harm nor help the host.

Symbioses can sometimes help the host species, sometimes harm the host, and sometimes neither harm nor help the host.

1. In a cleaner fish mutualism, which of the following is the most likely reason that a client fish associated with a cleaner fish like Labroides dimidatus?does not eat the cleaner fish, even when the cleaner fish is in its mouth? The client fish is being altruistic. The benefit the client fish receives from the cleaner fish in parasite removal is greater than what it would gain by eating the cleaner fish. The cleaner fish contains noxious secondary compounds that would harm the client fish. The cleaner fish emits a chemical that makes the other fish more docile.? The client fish does not like how the cleaner fish tastes.

The benefit the client fish receives from the cleaner fish in parasite removal is greater than what it would gain by eating the cleaner fish.