Elements of Ecology, 8e (Smith/Smith)
Chapter 12 Metapopulations
12.1 Short Answer Questions
1) A(n) ________ consists of a collection of local, interacting subpopulations that are linked by dispersal.
Answer: metapopulation
Topic: Introduction to Chapter 12
2) At the metapopulation, or regional, scale, population dynamics are governed by the interaction of ________ populations.
Answer: local Topic: Section 12.1
3) ________ involves the movement of individuals from occupied patches (existing local populations) to unoccupied patches to form new local populations.
Answer: Colonization Topic: Section 12.1
4) Metapopulation persistence is a dynamic balance between the ________ and recolonization of empty habitat patches.
Answer: extinction Topic: Section 12.2
5) The extinction rate (E) of a metapopulation ________ as the proportion of patches occupied (P) increases.
Answer: increases Topic: Section 12.2
6) Local population dynamics are influenced by patch size and ________. Answer: isolation
Topic: Section 12.3
7) Increasing patch size may influence the persistence of local populations by increasing the potential for environmental ________.
Answer: heterogeneity Topic: Section 12.4
8) The ________ effect refers to the increasing population size and decreasing risk of extinction that occurs with an increasing rate of immigration.
Answer: rescue Topic: Section 12.5
9) A(n) ________ population maintains a positive growth rate, producing a surplus of individuals that disperses to other local populations.
Answer: source Topic: Section 12.5
10) A(n) ________ population cannot support positive population growth and is able to persist only when individuals immigrate from other local populations.
Answer: sink Topic: Section 12.5
11) The ability of an organism to colonize available habitats is influenced by its rate of ________, which is affected by fecundity and mode of reproduction.
Answer: dispersal Topic: Section 12.7
12) Population densities are usually ________ in smaller species than in larger species. Answer: higher
Topic: Section 12.7
13) A(n) ________ is a collection of metapopulations in a geographic region that has evolved one or more characteristics distinguishing it from other metapopulations due to isolation and subsequent divergence resulting from natural selection.
Answer: subspecies Topic: Section 12.8
12.2 Multiple-Choice Questions 1) In a typical metapopulation,
A) suitable habitat is relatively patchy rather than uniform. B) only the smaller subpopulations are at risk of extinction.
C) the isolation of habitat patches prevents recolonization after local extinction. D) the dynamics of local populations are synchronized.
Answer: A
Topic: Section 12.1
2) In a metapopulation, regional scale population dynamics are governed primarily by the interaction of local populations, specifically
A) birth and death rates. B) dispersal and colonization. C) predation and parasitism. D) stochastic processes. Answer: B
3) The model of population dynamics developed by Richard Levins assumes that A) each patch contributes equally to the pool of emigrants.
B) patches are of different size.
C) the probability of extinction is the same for each local population. D) some patches supply more resources than others.
Answer: A
Topic: Section 12.2
4) In a metapopulation, the probability of extinction in a local population increases with A) increasing patch size and increasing isolation.
B) increasing patch size and decreasing isolation. C) decreasing patch size and increasing isolation. D) decreasing patch size and decreasing isolation. Answer: C
Topic: Section 12.3
5) In a metapopulation, the probability of recolonization in a local population increases with A) increasing patch size and increasing isolation.
B) increasing patch size and decreasing isolation. C) decreasing patch size and increasing isolation. D) decreasing patch size and decreasing isolation. Answer: B
Topic: Section 12.3
6) As the size of a habitat patch increases, A) environmental heterogeneity decreases. B) the probability of extinction increases. C) the probability of colonization decreases.
D) the impact of environmental stochasticity decreases. Answer: D
Topic: Section 12.4
7) The rescue effect on the size of a local population results from A) an increased birthrate.
B) a decreased death rate.
C) immigration from a nearby population. D) the extinction of predators.
Answer: C
Topic: Section 12.5 8) A source population
A) must be maintained by immigrants from a sink population. B) has a high rate of extinction.
9) The persistence of metapopulations increases when A) heterogeneity of habitat increases.
B) isolation of local populations increases. C) environmental stochasticity increases. D) the size of local populations decreases. Answer: A
Topic: Sections 12.3—12.6
10) Which of the following factors can synchronize metapopulation dynamics? A) death of immigrants
B) prevention of dispersal C) environmental stochasticity D) heterogeneous patch quality Answer: C
Topic: Section 12.6
11) The rate of dispersal is highest in species that A) occupy stable habitats.
B) occupy isolated habitats. C) reproduce asexually. D) have high fecundity. Answer: D
Topic: Section 12.7
12) Which of the following is the correct hierarchy of the population concept? A) local population < metapopulation < subspecies < species
B) metapopulation < local population < subspecies < species C) local population < metapopulation < species < subspecies D) metapopulation < local population < species < subspecies Answer: A
Topic: Section 12.8
13) In the equation, P = 1 - e / m, e represents the A) rate of local population colonization.
B) rate of local population extinction.
C) probability of local population colonization. D) probability of local population extinction. Answer: D
12.3 True/False Questions
1) The probability of core population extinction is less than that of satellite populations in a metapopulation.
Answer: TRUE Topic: Section 12.1
2) Dispersal of individuals among local populations does not occur within a metapopulation. Answer: FALSE
Topic: Section 12.1
3) The model of metapopulation growth is similar to the logistic model of population growth in that both are regulated by density-dependent factors.
Answer: TRUE Topic: Section 12.2
4) The ability of individuals to disperse among habitat patches is related to their degree of isolation.
Answer: TRUE Topic: Section 12.3
5) Increasing isolation of habitat patches can be compensated for by decreasing the average patch size.
Answer: FALSE Topic: Section 12.3
6) A large patch of habitat tends to be more spatially heterogeneous than a small patch of habitat. Answer: TRUE
Topic: Section 12.4
7) As heterogeneity of habitat in a local population increases, the population density fluctuates more.
Answer: FALSE Topic: Section 12.4
8) The rescue effect of a population decreases its risk of extinction. Answer: TRUE
Topic: Section 12.5
9) A source population is more likely than a sink population to become extinct. Answer: FALSE
Topic: Section 12.5
11) The rate of dispersal is greater in species occupying stable habitats than in those occupying temporary habitats.
Answer: FALSE Topic: Section 12.7
12) Sexually reproducing plants tend to have lower rates of local extinction than asexually reproducing plants.
Answer: FALSE Topic: Section 12.7
13) A species encompasses the largest geographic range in the four hierarchical levels of spatial aggregation of populations.
Answer: TRUE Topic: Section 12.8 12.4 Essay Questions
1) Describe the four conditions necessary for the term metapopulation to apply to a system of local populations.
Topic: Section 12.1
2) Describe the assumptions made to mathematically model metapopulation dynamics. Are these assumptions appropriate? Why or why not?
Topic: Section 12.2
3) Discuss the effects of patch area and isolation on the rates of colonization and extinction of a population, and how the size of the population may be affected.
Topic: Section 12.3
4) Explain the relationship between patch size and habitat heterogeneity. Why is habitat heterogeneity a benefit to a population?
Topic: Section 12.4
5) Describe the rescue effect of an isolated population and define sink and source populations. Topic: Section 12.5
6) Discuss three characteristics of species that affect their potential rates of colonization and extinction.
Topic: Section 12.7
7) Critique the classic definition of a population as "a group of organisms of the same species occupying a particular area at a particular time." Describe the alternative hierarchical approach for describing the concept of a population.
