Deck 53: Introduction to Ecology: Population Ecology

Question 1

Which of the following consists of organisms, all of which share a common gene pool?

A) A community
B) A population
C) A biosphere
D) An ecosystem
E) A landscape

Answer 1

B

Question 2

Which of the following is NOT a condition that is likely to lead to uniform population dispersion?

A) Nesting territoriality
B) Severe competition among individuals
C) Plant roots or shed leaves that produce toxic substances
D) Establishment of feeding or mating territories
E) Pressure from predation

Answer 2

E

Question 3

When r = −0.00057, the population size:

A) will increase.
B) will decrease.
C) is stable.
D) may increase or decrease, depending on K .
E) may increase or decrease, depending on i .

Answer 3

B

Question 4

What is perhaps the most common of the dispersal patterns seen in nature?

A) Random dispersion
B) Disaggregated dispersion
C) Uniform dispersion
D) Density-dependent distribution
E) Clumped dispersion

Question 5

Which set of values would result in a population with a growth rate of zero?

A) b = 1000, d = 500, i = 750, e = 1000
B) b = 1000, d = 500, i = 1000, e = 1000
C) b = 1000, d = 500, i = 1500, e = 1000
D) b = 1000, d = 500, i = 0, e = 1000
E) b = 1000, d = 500, i = 500, e = 1000

Question 6

Which of the following organisms would have the highest intrinsic rate of increase?

A) Bacteria
B) Blue whales
C) Red grouse
D) Elephants
E) Humans

Question 7

What would be the growth rate ( r ) of an island population of 1,000 that has 30 births per 100 population, 20 death per 100 population, 5 immigrants per 100 population, and 10 emigrants per 100 population?

A) +5
B) − 50
C) +50
D) − 150
E) +150

Question 8

Which of the following series correctly represents the hierarchical organization within ecology?

A) Ecosystem → population → community → biosphere
B) Biosphere → community → population → ecosystem
C) Community → population → ecosystem → biosphere
D) Population → community → ecosystem → biosphere
E) Population → ecosystem → community → biosphere

Question 9

At zero population growth:

A) b = d.
B) b > d.
C) b d.
D) r > 0.
E) r > K .

Question 10

The best definition of population density is the number of individuals:

A) of all species in a given area.
B) of one species in a given area.
C) in a given area at a given time.
D) of all species in a given area at a given time.
E) of one species in a given area at a given time.

Question 11

Which of the following is a correct statement regarding populations in biology?

A) A population is a group consisting of more than one species that all live together in a prescribed area at the same time
B) The boundaries of the area cannot be defined by an ecologist.
C) Populations exhibit characteristics distinctive from those of the individuals of which they are composed.
D) Populations have the same properties as communities.
E) Natural selection acts indirectly to produce adaptive changes in populations and directly affects the community level.

Question 12

What term refers to the average rate at which organisms produce offspring?

A) Doubling time
B) Natality
C) Emigration
D) Stasis
E) Survivorship

Question 13

When r = 0.00001, the population size:

A) will increase.
B) will decrease.
C) is stable.
D) may increase or decrease, depending on K .
E) may increase or decrease, depending on i .

Question 14

Natural selection acts most directly on:

A) populations.
B) communities.
C) ecosystems.
D) the biosphere.
E) K- selected organisms.

Question 15

Which of the following is NOT a condition that is likely to lead to clumped population dispersion?

A) Severe competition among individuals
B) Patchy distribution of resources in the environment
C) Presence of family groups and pairs
D) Limited seed dispersal or asexual reproduction
E) Pressure from predation

Question 16

Figure 53-1 ​

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The graph in the accompanying figure would best be described as:

A) being characteristic of exponential growth.
B) being characteristic of arithmetic growth.
C) an S-shaped curve.
D) a J-shaped curve.
E) being a J-shaped curve characteristic of exponential growth.

Question 17

Figure 53-1 ​

​
The equation that would best describe the curve in the accompanying figure is:

A) dN / dt = r .
B) dN / dt = N .
C) dN / dt = rN .
D) dN / dt = rN + I − e .
E) dN / dt = rN ( K − N ).

Question 18

The logistic equation:

A) models a J-shaped growth curve.
B) takes into account the carrying capacity of the environment.
C) predicts continued exponential growth.
D) characterizes the uncontrolled growth of a population.
E) models a K -shaped growth curve.

Question 19

Which of the following relationships is incorrectly paired?

A) Schooling fish-aggregated distribution
B) Nesting seabirds-random dispersion
C) Grove of aspen-clumped dispersion
D) Flour beetle larvae-random dispersion
E) Adult sand pine-uniform dispersion

Question 20

Clumped dispersion is often influenced by:

A) the presence of strange groups.
B) sexual reproduction in plants or invertebrates.
C) unlimited seed dispersal in plants.
D) a patchy distribution of resources.
E) homogenous environments.

Question 21

The growth rate of a population is expressed as:

A) b − d .
B) i − e .
C) K − N .
D) dN / r .
E) ( K − N ) / K .

Question 22

Which of the following is an INCORRECT statement regarding exploitation competition?

A) All individuals in a population "share" the limited resource more or less equally.
B) At high population densities, none of the individuals in a population obtains an adequate amount of the limited resource.
C) The populations often oscillate over time.
D) There is always a risk that the populations will drop to zero.
E) Red grouse populations exhibit exploitation competition.

Question 23

An example of a density-dependent factor that influences the size of a population is:

A) rainfall.
B) temperature.
C) a fire.
D) parasites.
E) an earthquake.

Question 24

Figure 53-2 ​

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On the accompanying figure, identify the point that indicates the carrying capacity for this population.

A) A
B) B
C) C
D) D
E) Cannot be determined from this graph.

Question 25

Figure 53-3 ​

​
Based on the accompanying figure, the decline in the moose population in 1996 was most likely due to a(n):

A) predictable increase in the wolf population.
B) unpredictable increase in the wolf population.
C) decrease in the intrinsic rate of increase for the moose population.
D) decline in the food supply.
E) unknown disease organism.

Question 26

Figure 53-5 ​

​
Refer to the accompanying figure. How would the survivorship curve for elephants be represented?

A) The curve A
B) The curve B
C) The curve C
D) Either A or C, depending on the species
E) Elephant populations would be better represented by a curve falling between A and B.

Question 27

Iteroparity is common in which of the following organisms?

A) Perennial herbaceous plants
B) Most insects
C) Agaves
D) Most invertebrates
E) Pacific salmon

Question 28

Two members of the same species compete for a limited resource, resulting in equal sharing of the limited resource. What is this called?

A) Interspecific scramble competition
B) Intraspecific scramble competition
C) Interspecific contest competition
D) Intraspecific contest competition
E) Density-independent competition

Question 29

Which factors are an example of a negative feedback system?

A) Density dependent
B) Density independent
C) Intraspecific competition
D) Interspecific competition
E) Scramble competition

Question 30

The potential capacity to produce offspring is called:

A) life history traits.
B) fitness.
C) age structure.
D) density.
E) fecundity.

Question 31

Refer to the accompanying figure. At which point do the environmental limits begin to slow the growth rate?

A) A
B) B
C) C
D) D
E) There are considerable environmental limits on all regions of the graph.

Question 32

What is a typical feature of K -selected organisms?

A) Early reproduction
B) Fast development
C) A low reproductive rate
D) Small body size
E) Little parental care of offspring

Question 33

Which of the following would increase population size?

A) Natality
B) Mortality
C) Emigration
D) An r less than 0
E) An r equal to 0

Question 34

Figure 53-5 ​

​
Refer to the accompanying figure. A population that produces a large number of offspring, but the offspring must survive independently, would be represented by the curve labeled:

A) A.
B) B.
C) C.
D) either A or B.
E) either A, B, or C.

Question 35

Density-independent factors:

A) influence population size and are in turn influenced by changes in population density.
B) may be the result of intense interspecific competition.
C) are typically abiotic.
D) may include parasites.
E) may include diseases.

Question 36

The moose population on Isle Royale is an example of:

A) interspecific exploitation competition.
B) intraspecific exploitation competition.
C) interspecific contest competition.
D) intraspecific contest competition.
E) both intraspecific contest competition and scramble competition.

Question 37

Generally, r -selected organisms exhibit:

A) short life spans and early maturity.
B) long life spans and extended parental care of offspring.
C) long development time to maturity, but small body size.
D) large body size and extended parental care of offspring.
E) large body size, but short life spans.

Question 38

When the size of a population begins to approach K, we can expect that the growth rate will:

A) rapidly increase.
B) slowly increase.
C) decline.
D) stabilize.
E) the answer is not predictable.

Question 39

Figure 53-3 ​

​
According to the data in the accompanying figure, the cause of the decline of the wolf population in 1982 was:

A) a sharp decrease in food supply.
B) a decrease in the intrinsic rate of increase for the wolf population.
C) competition with a newly introduced predator.
D) introduction of a disease organism.
E) cannot be determined from the data provided.

Question 40

Figure 53-2 ​

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Refer to the accompanying figure. At which point are there few environmental limits on the population?

A) A
B) B
C) C
D) D
E) There are considerable environmental limits on all regions of the graph.

Question 41

The British clergyman and economist Malthus was one of the first to recognize which of the following?

A) Human populations cannot continue to increase indefinitely.
B) Animals arrange themselves into populations.
C) Some species are r -strategists.
D) Some species are K -strategists.
E) Not all species can be classified as exclusively r -strategists or K -strategists.

Question 42

A human population that is shrinking would be characterized by a(n):

A) large proportion of prereproductive individuals.
B) small proportion of prereproductive individuals.
C) large proportion of reproductive individuals.
D) equal number of individuals of all age groups.
E) small proportion of postreproductive individuals.

Question 43

Organisms such as oysters or fish that produce millions of eggs per year may be characterized as:

A) r -selected and having a type I survivorship curve.
B) K -selected and having a type I survivorship curve.
C) r -selected and having a type II survivorship curve.
D) K -selected and having a type II survivorship curve.
E) r -selected and having a type III survivorship curve.

Question 44

In a human population with a high proportion of prereproductive individuals, the population will:

A) continue to increase even if the fertility rate is at replacement levels.
B) decline even if the fertility rate is at replacement levels.
C) increase only if the fertility rate is above replacement levels.
D) decline only if the replacement level fertility rate changes.
E) reach ZPG sooner than with a low proportion of prereproductive individuals.

Question 45

Figure 53-4 ​

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Which of the following species exhibits a mix of more than one type of survivorship over their life cycle?

A) Humans
B) Bison
C) Drummond flox
D) Oysters
E) Herring gulls

Question 46

A group of cacti on a sun-exposed slope have greater reproductive success than cacti on a shaded slope. The habitat on the sun-exposed slope can be classified as which of the following?

A) r -selected habitat
B) K -selected habitat
C) Both an r -selected and a K -selected habitat
D) Sink habitat
E) Source habitat

Question 47

A population that is divided into several local populations among which individuals occasionally disperse (emigrate and immigrate) is known as a:

A) metapopulation.
B) life table.
C) survivorship curve.
D) source population.
E) sink population.

Question 48

Which of the following have local reproductive success that is less than the local mortality?

A) Metahabitats
B) Sink habitats
C) Source populations
D) Source habitats
E) K-selected populations

Question 49

Which of the following pairs is incorrectly matched?

A) Highly developed countries-infant mortality rate close to 7 per 1000
B) Moderately developed countries-fertility rate near 2
C) Less developed countries-fertility rate near 5
D) Worldwide-27% of the population is less than 15 years old
E) United States-doubling time 100 years

Question 50

The world human population has increased dramatically during the past few centuries due to:

A) increased immigration.
B) increased emigration.
C) decreased death rates.
D) increased birth rates.
E) decreased birth rates.

Question 51

Figure 53-4 ​

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Based on the accompanying figure, which of the following age intervals has the highest death rate?

A) 0−1
B) 1−2
C) 2−3
D) 3−4
E) 4−5

Question 52

Highly developed countries are most likely to be characterized by which of the following?

A) High fertility rates
B) Low GNI PPPs
C) High doubling times
D) Low use of contraception
E) high infant mortality rates

Question 53

The average number of children born to a woman during her lifetime is known as:

A) age structure.
B) replacement-level fertility.
C) natality.
D) total fertility rate.
E) infant mortality rate.

Question 54

Trees are often long-lived, strongly competitive, produce thousands of offspring, and disperse their offspring widely. Trees are therefore often best described as having traits that are characteristic of which of the following:

A) r -strategists.
B) K -strategists.
C) both r - and K -strategists.
D) Type I survivorship.
E) Type II survivorship.

Question 55

Which of the following is NOT characteristic of a metapopulation?

A) Varying levels of precipitation, soil moisture, and other properties
B) Recolonization of vacant habitat
C) Heterogeneous species dispersal
D) Homogeneous species dispersal
E) Dispersal among several local populations

Question 56

By the end of the 21st century, it is expected that the human population will:

A) increase at the fastest rate in the highly developed countries.
B) increase at the fastest rate in the less developed countries.
C) increase at similar rates in all countries.
D) decrease at similar rates in all countries.
E) achieve zero population growth.

Question 57

Figure 53-6 ​

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Refer to the accompanying figure. Assuming the pattern remains the same, what will the population experience in 50 years?

A) Slow growth
B) Rapid growth
C) Steady state growth
D) Negative growth
E) No prediction can be made using these data

Question 58

The Earth's carrying capacity is:

A) 1 billion.
B) 1 million.
C) 4 billion.
D) 16 billion.
E) unknown.

Question 59

Figure 53-4 ​

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The accompanying figure is representative of:

A) exponential growth.
B) iteroparity.
C) Type I survivorship.
D) Type III survivorship.
E) Type II survivorship.

Question 60

Figure 53-6 ​

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Figure 53-6 represents the age structure diagram of:

A) the transition stage.
B) the preindustrial state.
C) a moderately developed country.
D) a developing country.
E) a highly developed country.

Question 61

In Type-I survivorship, the young have a high probability of surviving.

Question 62

Members of an r-selected species typically have a short lifespan.

Question 63

Scramble competition results when all individuals in a population share the limited resources.

Question 64

Compare and contrast Type I and Type III survivorship curves. Sketch a correctly labeled graph to support your comparison. BONUS: Identify two organisms that represent each of the two types of survivorship strategies discussed here.

Question 65

The largest population that can be maintained in an environment for an indefinite period of time is called the carrying capacity.

Question 66

Sketch an exponential growth curve with correctly labeled axes. Identify two organisms and describe the conditions under which they might demonstrate such growth.

Question 67

Explain the difference between semelparous and iteroparous species. Provide an example of each.

Question 68

A density-dependent factor is an example of a negative feedback system.

Question 69

Oysters have a(n) Type-II survivorship curve.

Question 70

An exponential growth curve has a J shape.

Question 71

Territoriality often results in clumped dispersion.

Question 72

An exponential growth curve levels off at the carrying capacity.

Question 73

The most common spacing is random dispersion.

Question 74

Interference competition is also called contest competition.

Question 75

A killing frost is an example of a density-independent factor.

Question 76

An example of a density-independent factor is predation.

Question 77

Species that exhibit repeated reproductive cycles are said to be semelparous.

Question 78

K strategists typically produce large numbers of offspring.

Question 79

The percentages of a population at different ages are known as the:

A) growth rate.
B) age structure.
C) biotic potential.
D) density.
E) fecundity.

Question 80

Most insects and invertebrates are said to be iteroparous.