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| 3445886365 | community | All of the species that interact in a certain area. | 0 | |
| 3445886366 | fitness | Ability to survive and produce viable, fertile offspring. | 1 | |
| 3445886367 | commensalism | A symbiotic relationship in which one organism benefits and the other is not harmed | 2 | |
| 3445886368 | competition | In ecology, the interaction of two species or two individuals trying to use the same limited resource. May occur between individuals of the same species. | 3 | |
| 3445886369 | mutualism | A symbiotic relationship between two organisms that benefits both. | 4 | |
| 3445886370 | coevolution | A pattern of evolution where two species influence each other's adaptations over time. | 5 | |
| 3445886371 | coevolutionary arms race | A repeating cycle of reciprocal adaptation. | 6 | |
| 3445886372 | intraspecific competition | Competition that occurs between members of the same species. | 7 | |
| 3445886373 | interspecific competition | Individuals from different species use the same limiting resources. | 8 | |
| 3445886374 | niche | The range of resources that the species is able to use, or the range of conditions it can tolerate. | 9 | |
| 3445886375 | symmetric competition | Ecological competition between two species in which both suffer similar declines in fitness. | 10 | |
| 3445886376 | asymmetric competition | Ecological competition between two species in which one species suffers a much greater fitness decline than the other. | 11 | |
| 3445886377 | competitive exclusion principle | Two species that occupy the same niche cannot coexist. | 12 | |
| 3445886378 | fundamental niche | The total theoretical range of environmental conditions that a species can tolerate. | 13 | |
| 3445886379 | niche differentiation | An evolutionary change in resource use, caused by competition over generations. | 14 | |
| 3445886380 | character displacement | The evolutionary change that occurs in species' traits, and that enables species to exploit different resources. | 15 | |
| 3445886381 | herbivory | The practice of eating plant tissues. | 16 | |
| 3445886382 | herbivores | An animal that eats primarily plants and rarely or never eats meat. | 17 | |
| 3445886383 | parasitism | A symbiotic relationship between two organisms that is beneficial to one organism but detrimental to the other. | 18 | |
| 3445886384 | parasite | An organism that lives on a host species or in a host species and that damages its host. | 19 | |
| 3445886385 | host | An individual that has been invaded by an organism such as a parasite or a virus, or that provides habitat or resources to a commensal organism. | 20 | |
| 3445886386 | predation | The killing and eating of one organism by another. | 21 | |
| 3445886387 | carnivores | An animal whose diet consists predominantly of meat, or other animals. | 22 | |
| 3445886388 | standing or constitutive defenses | A defensive trait that is always manifested even in the absence of a predator or pathogen. | 23 | |
| 3445886389 | mimicry | Pattern of one spieces resembling another. | 24 | |
| 3445886390 | Batesian mimicry | A type of mimicry in which a harmless or palatable species resembles a dangerous or poisonous species. | 25 | |
| 3445886391 | Mullerian mimicry | A type of mimicry in which two harmful species resemble each other. | 26 | |
| 3445886392 | inducible defenses | Physical, chemical, or behavioral defensive traits that are induced in the prey in response to the presence of a predator. | 27 | |
| 3445886393 | meta-analysis | A study of studies, meaning an analysis of a large number of data sets on a particular question. | 28 | |
| 3445886394 | integrated pest management | Strategies to maximize crop and forest productivity while using a minimum of insecticides or other types of potentially harmful compounds. | 29 | |
| 3445886395 | climax community | The stable, final community that develops from ecological succession. | 30 | |
| 3445886396 | plankton | Drifting organisms in aquatic environments. | 31 | |
| 3445886397 | keystone species | A species that has an exceptionally great impact on the other species in its ecosystem relative to its abundance. | 32 | |
| 3445886398 | food web | The network of exchanges of energy and nutrients among producers, consumers, and decomposers in an ecosystem. | 33 | |
| 3445886399 | disturbance | Any strong, short-lived disruption to a community that changes the distribution of living and/or nonliving resources. | 34 | |
| 3445886400 | disturbance regime | The characteristic disturbances that affect a given ecological community. | 35 | |
| 3445886401 | succession | In ecology, the gradual colonization of a habitat after an environmental disturbance, usually by a series of species. | 36 | |
| 3445886402 | primary succession | The gradual colonization of a habitat of bare rock or gravel, usually after an environmental disturbance that removes all soil and previous organisms. | 37 | |
| 3445886403 | secondary succession | Gradual colonization of a habitat after an environmental disturbance that removes some or all previous organisms but leaves the soil intact. | 38 | |
| 3445886404 | pioneering species | Those species that appear first in recently disturbed areas. | 39 | |
| 3445886405 | weed | A plant that is adapted for growth in disturbed soils. | 40 | |
| 3445886406 | facilitation | In ecological succession, the phenomenon in which early-arriving species make conditions more favorable for later-arriving species. | 41 | |
| 3445886407 | tolerance | In ecological succession, the phenomenon in which early-arriving species do not affect the probability that subsequent species will become established. | 42 | |
| 3445886408 | inhibition | In ecological succession, the phenomenon in which early-arriving species make conditions less favorable for the establishment of certain later-arriving species. | 43 | |
| 3445886409 | species richness | A simple count of how many species are present in a given community. | 44 | |
| 3445886410 | species diversity | A weighted measure that incorporates the species' relative abundance. | 45 | |
| 3445886411 | Explain why niche differentiation does not involve a conscious choice by the individuals involved. | The individuals do not choose or try to have traits that reduce competition--they simply have those traits (or not). Resource partitioning just happens, because individuals with traits that allow them to exploit different resources produce more offspring, which also have those traits. | 46 | |
| 3445886412 | Explain what a coevolutionary arms race is and give an example. | When species interact via consumption, a trait that gives one species an advantage will exert natural selection on individuals of other species who have traits that reduce that advantage. This reciprocal adaptation will continue indefinitely. An example is the interaction of Plasmodium with the human immune system: The human immune system has evolved the ability to detect proteins from the Plasmodium and kill infected cells; in response, Plasmodium has evolved different proteins that the immune system does not detect. | 47 | |
| 3445886413 | Explain how early successional species after the environment in ways that make growing conditions more difficult for themselves. | The shade provided by early successional species increases humidity, and decomposition of their tissues adds nutrients and organic material to the soil. These conditions favor growth by later successional species, which can outcompete the early successional species. | 48 | |
| 3445886414 | Explain how the presence or absence of a species like alder, where nitrogen fixation occurs, might alter the course of succession. | The presence of absence of a plant species where nitrogen fization occurs would dramatically alter nutrient conditions, and thus the speed of succession and the types of species that could become established. For example, species that require high nitrogen would be favored on sites where alder grew, and species that can tolerate low nitrogen would thrive on sites where alder is absent. | 49 | |
| 3445886415 | You should be able to give an example of how mutualistic relationship can evolve into a parasitic one. | A mutualistic relationship becomes a parasitic one if one of the species stops receiving a benefit. The treehopper-ant mutualism becomes parasitic in years when spiders are rare, because the treehoppers no longer derive a benefit but pay a fitness cost. | 50 | |
| 3445886416 | You should be able to predict the effects of an invasive species on community structure. | An invasive species could have a large impact on community structure by replacing the dominant plant species that creates physical structure, which in turn affects other members of the community; by replacing a keystone species that has an indirect effect on many other species; or by outcompeting many species, causing a direct reduction in species richness. | 51 | |
| 3445886417 | You should be able to explain why climate makes the three successional pathways documented in Glacier Bay similar, and why chance historical events make them different. | All species at Glacier Bay must be able to survive cold climate with the local amount of precipitation. The species earliest in the successsion must also be able to grow in rock exposed as the glacier melts. But change, historical differences in seed sources, and presence or absence of alder created differences in the species present. | 52 | |
| 3445886418 | You should be able to propose how the theory of island biogeography could be applied by conservation biologists to species richness in a national park. | Many national parks are surrounded by altered habitats, so they are functionally similar to islands. Species richness in the park is more likely to be preserved if it is large and located nearby other wilderness areas. | 53 | |
| 3445886419 | True or False? Species act as agents of natural selection when they interact. | True | 54 | |
| 3445886420 | What is a niche differentiation? | the evolution of traits that reduce niche overlap and competition | 55 | |
| 3445886421 | The relationship between ants and treehoppers in the presence of spider is an example of | mutualism | 56 | |
| 3445886422 | What is one advantage of inducible defenses? | They make efficient use of resources, because they are produced only when needed. | 57 | |
| 3445886423 | Pioneer species tend to have high ____ and lower survivorship. | fecundity | 58 | |
| 3445886424 | Which of these factors is not generally correlated with species diversity? | longitude | 59 | |
| 3445886425 | The text claims that species interactions are conditional and dynamic. Do you agree with this statement? Why or why not? Cite species examples to support your answer. | Yes-- the treehopper-ant mutualism is parasitic or mutualistic, depending on conditions; competition can evolve into no competition over time if niche differentiation occurs; arms races mean that the outcome of host-parasite interactions can change over time, and so forth. | 60 | |
| 3445886426 | Why does the phrase "coevolutionary arms race" appropriately characterize the long-term effects of species interactions? | Adaptations that give one species a fitness advantage in an interaction are likely to be countered by adaptations in the other species that eliminate this advantage. | 61 | |
| 3445886427 | Biologists have tested the hypotheses that communities are highly predictable versus highly unpredictable. State the predictions that these hypotheses make with respect to (a) changes in the distribution of the species in a particular community over time and (b) the communities that should develop at sites where abiotic conditions are identical. Which hypothesis appears to be more accurate? | (a) If a community composition is predictable, then the species present should not change over time. But if composition is not predictable, then species should undergo significant changes over time. (b) If community composition is predicatble, then the two sites with identical abiotic factors should develop identical communities. If community composition is not predictable, then sites with identical abiotic factors should develop variable communities. In most tests, the data best match the predictions of the "not predictable" hypothesis, though communities show elements of both. | 62 | |
| 3445886428 | What is a disturbance? Consider the role of fire in a forest. Compare and contrast the consequences of high-frequency versus low-frequency fire, and high versus low severity fire. | Disturbance is any short-lived event that changes the distribution of resources. Compared to low-frequency fires, high-frequency fires would tend to be less severe and would tend to exert more intense natural selection for adaptations to resist the effects of fire. Compared to low-severity fires, high severity fires would open up more space of pioneering species and would tend to exert more intense natural selection for adaptations to resits the effects of fires. | 63 | |
| 3445886429 | Summarize the life-history attributes of early successional species. Why are these attributes considered adaptations? | Early successional species are adapted to disperse to new environments (small seeds) and grow and reproduce quickly (reproduce at an early age, grow quickly). they can tolerate severe abiotic conditions (high temperature, low humidity, low nutrient availability) but have little competitive ability. These species are able to enter a new environment (with no competitors) and thrive. These attributes are considered adaptations because they increase the fitness of these species. | 64 | |
| 3445886430 | Explain why high productivity should lead to increased species richness in habitats such as tropical rain forests and coral reefs. | The idea is that high productivity will lead to high population density of consumers, leading to competition and intense natural selection favoring niche differentiation that leads to speciation. | 65 | |
| 3445886431 | Some insects harvest nectar by chewing through the wall of the structure that holds the nectar. As a result, they obtain a nectar reward, but pollination does not occur. Suppose that you observed a certain bee species obtaining nectar in this way from a particular orchid species. Over time, how might you expect the characteristics of the orchid population to change in response to this bee behavior? | Natural selection will favor orchid individuals that have traits that resist bee attack: thicker flower walls, nectar storage in a different position, a toxin in the flower walls, and so on. Individuals coud also be favored if their anthers were in a position that acoomplished pollination even if bees eat through the walls of the nectar-storage structure. | 66 | |
| 3445886432 | You are walking, talking community that includes trillions of bacterial and archeal cells. Your gut, in particular, contains a complex microbial community. In some circumstances, the use of probiotics, which stimulate the rapid growth of bacteria that are mutualistic or commensal with humans, can eliminate the need to use antibiotics, which can wipe out helpful bacteria along with harmful bacteria. The use of probiotics is an example of which process? | competitive exclusion | 67 | |
| 3445886433 | Suppose that a two-acre lawn on your college's campus is allowed to undergo succession. Describe how species traits, species interactions, and the site's history might affect the community that develops. | The exact answer will depend on the location of the campus. The first species to appear must posses good dispersal ability, rapid growth, quick reproductive periods, and tolerance for very harsh and sever conditions. The two-acre plot is likely to be colonized first by pioneer species that have very "weedy" characteristics. But once colonization is under way, the course of succession will depend more on how the various species interact with each other. The presence of one species can inhibit of facilitate the arrival and establishment of another. For example, an early-arriving species might provide the shade and nutrients required by a late-arriving species. The site's history and nearby ecosystems may influence which species appear at each stage; for instance, an undisturbed ecosystem nearby could be a source for native species. The pattern and rate of this succession is also influenced by the overall environmental conditions affecting it. Only species with traits appropriate to the local climate are likely to colonize the site. | 68 | |
| 3445886434 | Design an experiment to test the hypothesis that increasing species richness increases a community's productivity. | One reasonable experiment would involve constructing artificial ponds and introducing different numbers of plankton species to different ponds, but the same total number of individuals. (Any natural immigration to the ponds would have to be prevented.) After a period of time, remove all of the plankton and measure the biomass present. Make a graph with number of species on the x-axis and total biomass on the y-axis. If the hypothesis is correct, the line of best fit through the data should have a positive slope. | 69 |
