Campbell Biology: Concepts and Connections, 8e (Reece et al.)
Chapter 36 Population Ecology
36.1 Multiple-Choice Questions
1) A group of individuals of a single species that occupy the same general area defines a
A) population.
B) community.
C) subspecies.
D) clone.
2) Which of the following is an example of a population?
A) all of the microorganisms on your skin
B) all of the students in your classroom
C) all students attending colleges and universities in your state
D) the various plants found in prairies in the western United States
3) Assume that there are five alligators per acre in a swamp in northern Florida. This is a
measure of the alligator population’s
A) dispersion.
B) intrinsic rate of increase.
C) range.
D) density.
4) The pattern of distribution for a certain species of kelp is clumped. The pattern of distribution
for a population of snails that live on the kelp would be
A) clumped.
B) homogeneous.
C) random.
D) uniform.
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5) You drive through Iowa in the spring and notice that along a stretch of several kilometers,
every third fence post has a male redwing blackbird perched on it defending its nesting territory.
This is an example of
A) clumped dispersion.
B) random dispersion.
C) uniform dispersion.
D) artificial dispersion.
6) The density of Douglas firs in an old-growth forest is estimated by counting the Douglas firs
in four sample plots of 1 hectare each. The number of fir trees in the plots is 10, 12, 7, and 11,
respectively. What is the estimated density of firs in the forest?
A) 5 trees per hectare
B) 10 trees per hectare
C) 20 trees per hectare
D) 25 trees per hectare
7) To obtain optimal production in a small garden, one should
A) plant seeds in rows with minimal spacing between rows.
B) plant seeds in clumps with large spaces between clumps.
C) plant seeds in a uniform pattern throughout the garden.
D) sow seeds randomly throughout the garden.
8) A survivorship curve is a
A) graph that plots an individual’s likelihood of reproducing as a function of age.
B) graph that plots an individual’s likelihood of being alive as a function of age.
C) graph that shows the effect of predation on a prey population.
D) model for population growth that incorporates the concept of carrying capacity.
9) A Type I survivorship curve is associated with which of the following life history traits?
A) parents providing extended care for their young
B) large numbers of offspring being produced
C) infant mortality being much greater than adult mortality
D) a short life span for most individuals
10) A survivorship curve that involves producing very few offspring, each of which has a high
probability of surviving to adulthood, is typical of
A) sea stars.
B) elephants.
C) oysters.
D) rodents.
11) The maximum number of individuals a habitat can support is called its
A) reproductive potential.
B) carrying capacity.
C) community size.
D) density-dependent factor.
12) Consider a stable frog population living at carrying capacity in a pond. If an average female
produces 6,000 eggs during her lifetime and an average of 300 tadpoles hatch from these eggs,
how many of these tadpoles will, on average, survive to reproduce?
A) 0
B) 2
C) 10 to 20
D) more than 100
13) A population of fungi in a yard produces 10 mushrooms in year 1, 20 in year 2, and 40 in
year 3. If this trend continues, by year 5 there will be ________ mushrooms.
A) 40
B) 80
C) 160
D) 320
14) A newly mated queen ant establishes an ant nest in an unoccupied patch of suitable habitat.
The population of the nest grows quickly at first, then levels off at carrying capacity. Which of
the following models best describes its population growth?
A) linear
B) logarithmic
C) logistic
D) exponential
15) A test tube is inoculated with 1 × 103 cells of a bacterial strain that has a generation time of
30 minutes. The carrying capacity of the test tube for this strain is 6 × 109 cells. What will the
bacterial population be after 90 minutes of culturing?
A) 3 × 103
B) 8 × 103
C) 1 × 109
D) 6 × 109
16) If an ecosystem has a carrying capacity of 1,000 individuals for a given species and 2,000
individuals of that species are present, we can predict that the population
A) size will remain at equilibrium.
B) size will decrease.
C) will show a clumped dispersion pattern.
D) size will slowly increase.
17) If a population has a birth rate of 40 individuals per 1,000 per year and a death rate of 30
individuals per 1,000 per year, how will the population change each year? (Assume that the
population is below carrying capacity and that there is no immigration or emigration.)
A) It will decrease by 70%.
B) It will increase by 1%.
C) It will increase by 5%.
D) It will increase by 100%.
18) A human population will achieve zero population growth if
A) no couple has more than two children.
B) couples have an average of about 2.25 children each (to account for some children who do not
survive to reproduce).
C) no couple has more than one child.
D) the birth rate equals the intrinsic rate of increase r.
19) The death by bubonic plague of about one-third of Europe’s population during the 14th
century is a good example of
A) abiotic factors limiting population size.
B) a density-dependent effect.
C) a density-independent effect.
D) carrying capacity.
20) A tidal wave wipes out the entire population of mice living on an island. This is an example
of
A) Type III survivorship.
B) a density-dependent effect.
C) the effects of abiotic factors.
D) the interaction between density-dependent and abiotic factors.
21) In the logistic growth model, as population size increases, birth rates
A) remain constant and death rates increase.
B) decline but death rates remain steady.
C) and death rates increase.
D) decline and/or death rates increase.
22) Which of the following is most clearly a case of density-dependent population regulation?
A) the summer drying of savanna grass for an insect that feeds on grass sap
B) a dangerous new flu strain that is transmitted among humans by sneezing
C) the first hard frost of fall for a population of annual morning glory vines
D) the occurrence of rainstorms for an opportunistic desert annual
23) In terms of population dynamics, what is “boom-and-bust” cycling?
A) a situation in which a population moves back and forth between rapid growth and decline
B) a situation in which a growing population overshoots the carrying capacity of its environment
and experiences a crash before stabilizing
C) a situation in which the sex ratio in a population shows repeated oscillations
D) a situation in which the populations of a predator species and a prey species oscillate in
unison
24) An ecologist hypothesizes that predation by a particular owl species is the major factor
controlling the population of a particular rabbit species. The first step in testing this hypothesis
would be to determine
A) whether populations of the rabbit that live outside the range of the owl have higher population
densities.
B) whether the owls eat the rabbits.
C) to which diseases the rabbit population is subject.
D) what food the rabbits eat.
25) An ecologist hypothesizes that predation by a particular owl species is the major factor
controlling the population of a particular rabbit species. If this is the case, which of the following
population effects could be expected in this rabbit-owl pair?
A) A fall in the owl population should cause a fall in the rabbit population.
B) A fall in the rabbit population should cause an increase in the owl population.
C) An increase in the incidence of disease in the rabbit population should not change the owl
population.
D) An increase in the owl population should cause a fall in the rabbit population.
26) An r-selected species typically
A) offers considerable parental care to offspring.
B) has an advantage in habitats that experience unpredictable disturbances.
C) is large-bodied and long-lived.
D) lives in stable climates.
27) Which of the following organisms best illustrates K-selection?
A) the production of thousands of eggs every spring by frogs
B) mice that produce three litters of 10-15 babies in the course of a summer
C) a polar bear producing one or two cubs every three years
D) a species of weed that quickly spreads into a region of cleared trees
28) Guppies from Trinidad form two distinct populations that differ in several life history traits.
These traits appear to relate to the local predator populations, pike-cichlids or killifish. Which of
the following experiments would best test the heritability of these traits?
A) Raise both populations with cichlids to see if the population of smaller, faster-maturing
guppies reproduces more quickly.
B) Raise both populations without predators to see if they maintain their life history traits.
C) Introduce cichlids into a habitat with killifish.
D) Provide additional food to the guppies from cichlid habitats to see if they will grow to the
same size as guppies from the killifish habitat.
29) Which of the following will likely decrease a population’s size?
A) improving the quality of its habitat
B) increasing the size of its habitat
C) practicing sustainable resource management in its habitat
D) decreasing the food supply available to the population
30) Which of the following statements about insecticides is true?
A) To control agricultural pests, pest management uses biological controls, chemicals, or cultural
methods, but never a combination of these.
B) Simply killing many individuals is often the best way to reduce the size of a pest population.
C) Most insecticides kill the pest but not the pest’s natural predators.
D) Prey species often have a higher reproductive rate than do predators.
31) Which of the following statements about human population growth is true?
A) Human population size on Earth today is at equilibrium.
B) Demographic transition is a transition from high birth rates and high death rates to low birth
rates and low death rates.
C) During a demographic transition, birth rates typically drop first due to the availability of
reliable contraception.
D) Human population size has increased faster and faster throughout human history.
32) A demographic tool used to predict a population’s future growth is
A) a Type III survivorship curve.
B) a demographic transition.
C) age structures.
D) a Type I survivorship curve.
33) What is the age structure of a population?
A) the curve that results when the likelihood of dying is plotted as a function of age
B) the curve that results when the likelihood of being alive is plotted as a function of age
C) the proportion of individuals alive in different age-groups
D) the difference in the age distribution of a population at two different points in time
34) If most of the individuals of a human population are in their pre-reproductive years, you
would expect the population size to ________ after 20 years.
A) stay the same
B) increase
C) decrease
D) decrease and then stabilize
35) Which of the following statements about human demographic trends is true?
A) As women’s status and education increase, they choose to have more children.
B) After 1950, mortality rates increased rapidly in most developing countries.
C) A human population in which women reproduce at a later age will experience slower
population growth.
D) The movement from high birth rates and low death rates to low birth rates and high death
rates is called the demographic transition.
36) The age structure of the United States in 2010 shows
A) a broad base, suggesting a high birth rate.
B) a broad base, suggesting a low birth rate.
C) that a greater proportion of the population is elderly now than in earlier decades.
D) that the United States has not yet gone through a demographic transition.
37) The world human population
A) is growing faster now than ever before.
B) is growing, but at a slower rate than in the last century.
C) has leveled off at carrying capacity.
D) is starting to decline.
38) The human population on Earth is expected to reach 9.5 billion people by
A) 2015.
B) 2050.
C) 2093.
D) 3150.
39) An ecological footprint
A) is a means of determining increases in populations that lived in the past.
B) is a means of understanding resource availability and usage.
C) measures dispersion and adaptability.
D) will estimate population movements.
40) Thanks to a new conservation program, a population with only 200 individuals at the
beginning of the year is growing exponentially. The population has a per capita birth rate of 0.5
per year and a death rate of 0.2 per year. What is the growth rate during the year? What will the
population be at the end of the year?
A) growth rate = 60 per year; population = 260
B) growth rate = 6 per year; population = 206
C) growth rate = 260 per year; population = 60
D) growth rate = 30 per year; population = 230
41) If a population of 5,000 zebras is growing logistically and has a carrying capacity of 10,000,
what would the per capita rate of increase be if the population grew by 50 zebras in one year?
A) 0.2
B) 0.1
C) 0.02
D) 0.01
42) The African country of Nigeria had a 4.55% population growth rate from 2005 to 2010, the
highest in the world. Which of the following statements is consistent with this fact?
A) Nigeria’s age structure likely looks like a pyramid with a broad base.
B) Nigerian birth rates are likely to be slightly lower than death rates.
C) Nigeria is likely in the first phase of the demographic transition.
D) Nigerian emigration rates are likely higher than immigration rates.
43) Which of the following activities would result in a decrease in your ecological footprint?
A) flying across the United States once a month
B) driving your car to and from school every day
C) leaving the water running while you brush your teeth
D) taking a city bus instead of driving to work
44) What kind of curve represents exponential growth?
A) ascending straight line
B) J-shaped
C) S-shaped
D) descending straight line
45) A population of deer has a per capita rate of increase of 0.1 deer per year. If there are initially
300 deer in the population, and the population is growing exponentially, how many deer will be
in the population after one year?
A) 30
B) 300
C) 330
D) 600
46) Which of the following statements regarding logistic growth is true?
A) The parameter (K – N)/K is always equal to zero.
B) There has to be more than one limiting factor in place for logistic growth to occur.
C) Population growth is highest when the population is much larger than the carrying capacity.
D) Population growth is zero when (K – N)/K is equal to zero.
47) Which of the following is a practical application of population ecology that will result in
population decline?
A) restricting the length of deer hunting season
B) managing crops by selectively killing agricultural pests
C) removing habitat space from wild animal populations
D) preventing the overfishing of cod
36.2 Art Questions
1) According to this graph of the population growth of fur seals, in what year did the population
first reach its carrying capacity?
A) 1925
B) 1930
C) 1940
D) 1950
2) According to this graph of population growth in Mexico, in what year was the rate of
population increase in Mexico the greatest?
A) 1912
B) 1930
C) 1965
D) 2000
3) Examine the age structure of Germany in the figure below. Which of the following statements
is not supported by the age structure?
A) There will be large positive population growth in the near future.
B) There are more women than men between the ages of 60 and 70.
C) There will be small negative population growth in the near future.
D) There are more people between the ages of 25 to 39 then between 0 and 14.
36.3 Scenario Questions
After reading the paragraph below, answer the questions that follow.
You are a member of an African family that has been displaced from their home by civil war, so
you are trying to select a new country in which to settle to gain better economic opportunities.
You know that Nigeria is a large country with rich natural resources, so you are considering it for
your new home. Among the data you find while researching Nigeria is the following diagram of
the current age structure of the country.
1) The age structure data for Nigeria shows that the country has many more individuals under the
age of 15 than over the age of 40. What does this imply about the future population of Nigeria?
A) The population will probably remain stable.
B) The population will probably decrease.
C) The population will probably grow rapidly.
D) The number of older people will probably increase rapidly.
2) Based on the age structure of the country, which of the following situations would be most
likely to occur over the next 20 years?
A) strong economic gains stimulated by population growth
B) an increased demand for resources based on population growth
C) a decreased demand for medical services due to the small number of elderly citizens
D) a decline in housing prices based on lack of demand
3) Which of the following statements about the age structure of Nigeria is false?
A) The population of males and females ages 0 to 4 is approximately the same.
B) The population of males ages 15 to 19 is smaller than the population of females ages 5 to 9.
C) There are approximately 28 million males in Nigeria ages 0 to 14.
D) The population of females ages 40 to 44 is smaller than the population of males ages 65 to 69.