Chapter 54 Mastering Biology: Community Ecology

Commensalism is ________. A. an interaction between species that benefits one of the species but neither harms nor helps the other species B. an interspecific interaction that benefits both species C. an interaction where species have positive effects on the survival and reproduction of other species without necessarily living in the direct and intimate contact of symbiosis D. a symbiotic interaction in which one organism derives nourishment from another organism E. the beginning of an ecological interaction between two species

A. an interaction between species that benefits one of the species but neither harms nor helps the other species

The sum of a species' use of the biotic and abiotic resources in its environment is called __________. A. its ecological niche B. a demographic transition C. its ecological footprint D. a community E. the carrying capacity of the area

A. its ecological niche

_________ is the tendency of characteristics to diverge more in sympatric than in allopatric populations. A. Competitive exclusion B. Character displacement C. Carrying capacity of the area D. Resource partitioning E. A demographic transition

B. Character displacement

A species of malaria-carrying mosquito lives in a forest in which two species of monkeys, A and B, coexist. Species A is immune to malaria, but species B is not. The malaria-carrying mosquito is the chief food for a particular kind of bird in the forest. If all these birds were suddenly eliminated by hunters, which of the following would be an immediately observable consequence? A. Emergence of malaria-sensitive strains in monkey species A B. Increased mortality in monkey species B C. Increased mortality (death rate) in monkey species A D. Increased mortality in the malaria-carrying mosquitoes E. Emergence of malaria-resistant strains in monkey species B

B. Increased mortality in monkey species B

Certain species of acacia trees in Central and South America have hollow thorns that house stinging ants, which attack anything that touches the tree. The ants feed on nutrients produced by the acacias. This is an example of __________. A. commensalism B. mutualism C. facilitation D. parasitism E. predation

B. mutualism

The flower fly resembles a honeybee, but the flower fly has no stinger. This is an example of __________. A. Müllerian mimicry B. interspecific competition C. Batesian mimicry D. cryptic coloration

C. Batesian mimicry

The order of the stages of primary succession beginning with glacial retreat as seen at Glacier Bay, Alaska, are ________. A. Pioneer, Dryas, Spruce, and Alder stages B. Pioneer, Alder, Dryas, and Spruce stages C. Pioneer, Dryas, Alder, and Spruce stages D. Pioneer, Spruce, Alder, and Dryas stages E. Pioneer, Spruce, Dryas, and Alder stages

C. Pioneer, Dryas, Alder, and Spruce stages

What happens to the number of species in a community as the area of that community increases? A. The area of the community is not involved in determining the number of species present. B. The number of species does not change. C. The number of species in the community increases. D. None of the listed responses is correct. E. The number of species drops.

C. The number of species in the community increases.

What is the key difference between a dominant species and a keystone species? A. Keystone species are more successful at evading their predators and the impacts of disease. B. The removal of a dominant species from a community has more impact than removing a keystone species. C. While dominant species are the most abundant, keystone species exert control through important roles or niches. D. There is no difference. The two terms are synonymous. E. Dominant species alter the structure or dynamics of the environment; keystone species are the most abundant.

C. While dominant species are the most abundant, keystone species exert control through important roles or niches

A leech that attaches itself to a swimmer is an example of __________. A. an endoparasite B. prey C. an ectoparasite D. a pathogen E. a parasitoid

C. an ectoparasite

A group of populations of different species living close enough to interact is called a __________. A. family B. biome C. biological community D. clade

C. biological community

A diagram of the trophic relationships of a community showing who eats whom is called a(n) __________. A. marine food chain B.terrestrial food chain C. food web D. Productivity chart E. energetic hypothesis

C. food web

Similar species can coexist in a community by using _________. A. competitive exclusion B. predation C. resource partitioning D. a demographic transition E. character displacement

C. resource partitioning

A zoonotic pathogen is _________. A. transferred from humans to animals in zoos B. transferred from animals to animals C. transferred to humans from other animals D. transferred from humans to humans E. transferred from humans to other animals

C. transferred to humans from other animals

The poison-arrow frogs Dendrobates of tropical America are all brightly colored and have very similar patterns. Although each species is distasteful to predators and all possess toxic skin secretions, some of the species live quite separate from the others. The adaptive relationship among these species is best termed __________. A. parasitism B. commensalism C. Batesian mimicry D. Müllerian mimicry E. cryptic coloration

D. Müllerian mimicry

_________ is used to compare the diversity of communities across time and space. A. Relative abundance B. Species diversity C. Community diversity D. Shannon diversity E. Species richness

D. Shannon diversity

Flounder is a type of fish that looks like the seafloor. This is an example of __________. A. Müllerian mimicry B. warning coloration C. Batesian mimicry D. cryptic coloration E. character displacement

D. cryptic coloration

The relationship between an organism and individuals of other species in a community involves _________. A. a demographic transition B. an ecological niche C. an ecological footprint D. interspecific interactions E. carrying capacity of the area

D. interspecific interactions

In an area where soil has not yet formed, called primary succession, the life-forms that are first found are _________. A. worms and lichens B. protists and annelid worms C. worms and shrubs D. prokaryotes and protists E. lichens and mosses

D. prokaryotes and protists

In the North Pacific, sea otters are keystone predators. A reduction in their numbers has resulted in what changes in the marine community? A. Orcas beginning to prey on sea urchins B. Mutualism among prey species, which maintained species diversity C. Resource partitioning, allowing otherwise competing species to coexist D. Competitive exclusion, which reduced species richness E. Decreased community diversity

E. Decreased community diversity

Under which of the following circumstances would interspecific competition be most obvious? A. Among species whose trophic levels are different B. In the presence of a keystone species C. When resources are most abundant D. When organisms have quite different ecological niches E. When a nonnative organism is introduced to a community

E. When a nonnative organism is introduced to a community

Succession of communities occurs because __________. A. resources in an area are limited B. climatic changes lead to reduced water availability C. most populations have a limited life span and die, making room for others D. None of the listed responses is correct. E. each existing community changes the environment

E. each existing community changes the environment

Examples of defensive adaptations include all of the following except ________. A. aposematic coloration B. Müllerian mimicry C. mechanical defense D. Batesian mimicry E. predation

E. predation

When interspecific competition has an outcome called competitive exclusion, _________. A. the inferior competitor will continue to reside in the niche but at reduced numbers B. both species will become extinct C. the superior competitor will find a way to make room for the other species D. both species will continue to coexist E. the inferior competitor will be eliminated

E. the inferior competitor will be eliminated