Deck 52: Population Ecology

Question 1

Population dispersion is the ____.

A) statistical description of the relative numbers of individuals in each age class
B) number of individuals per unit area
C) number of individuals in a population
D) average time between the birth of an organism and the birth of its offspring
E) spatial distribution of individuals within a geographical range

Answer 1

E

Question 2

Population growth of rabbits in Australia can best be described as ____.

A) fast
B) exponential
C) virulent
D) stable
E) epidemic

Answer 2

B

Question 3

A population's ____ is the number of individuals in the population at a specific time.

A) growth rate
B) geographical range
C) size
D) habitat
E) dynamics

Answer 3

C

Question 4

Rabbits introduced to Australia overpopulated because in their new habitat, ____.

A) people rarely hunted them
B) they had no natural diseases
C) they had no natural predators
D) their food supply was larger
E) there were few herbivorous competitors

Question 5

The ____ method is often used to estimate the population size of mobile animals that live within a restricted geographic range.

A) mark-release-recapture
B) direct count
C) extrapolation of counts from quadrants to entire population
D) plot
E) indirect count

Question 6

Males have little influence on population growth in populations with ____.

A) more males than females
B) more females than males
C) equal numbers of females and males
D) one male
E) animals that form lifelong pairs

Question 7

What was the long-term effect of the introduction of myxoma virus to control rabbits in Australia?

A) The rabbits were all killed.
B) Most rabbits became immune to the virus.
C) The virus killed off some of the rabbit population but also infected kangaroos and wallabies.
D) The virus became less virulent and the rabbits gained some immunity.
E) The virus had no effect.

Question 8

Why do species with large body sizes typically have lower population densities?

A) each large organism consumes more available resources
B) there are not enough individuals to grow the population
C) genetic diversity is low
D) small organisms have more potential mates
E) large organisms do not like living near one another

Question 9

Which population dispersion is the most common in nature?

A) random
B) clumped
C) uniform
D) dynamic
E) unpredictable

Question 10

Which statement describes the general relationship between population density and body size?

A) Population density increases with increasing body size.
B) Population density is equal to body size.
C) Population density decreases with increasing body size.
D) Population density is not related to body size.
E) Population density first decreases then increases with increasing body size.

Question 11

An increase in generation time with increasing body size is least likely in ____.

A) bacteria
B) plants
C) animals
D) protists
E) fungi

Question 12

Which of these species' population growth rate is least affected by the number of males?

A) northern elephant seals
B) trumpeter swans
C) Canadian geese
D) European rabbits
E) Norwegian rats

Question 13

To estimate population size using the mark-release-recapture method, ____ samples must be captured.

A) 1
B) 2
C) 3
D) 4
E) 5

Question 14

Populations in which individuals repel each other because resources are in short supply tend to have ____ dispersion.

A) random
B) clumped
C) uniform
D) dynamic
E) unpredictable

Question 15

A population of mostly ____ individuals with a ____ generation time and a ____ proportion of females is expected to show the most growth in the future.

A) prereproductive; short; high
B) reproductive; short; low
C) reproductive; long; low
D) postreproductive; long; low
E) prereproductive; short; low

Question 16

Which group exhibits the longest generation time?

A) bacteria
B) plants
C) animals
D) protists
E) fungi

Question 17

Answer the question using the accompanying figure. Sea turtles are likely to die when they are young but have a good chance of surviving once they reach large size. Which survivorship curve best fits this species?

A) Type I, which is graph A
B) Type II, which is graph B
C) Type I, which is graph C
D) Type III, which is graph C
E) Type III, which is graph A

Question 18

Populations in which environmental conditions don't vary much within a habitat tend to have ____ dispersion.

A) random
B) clumped
C) uniform
D) dynamic
E) unpredictable

Question 19

The density of a population is defined as the ____.

A) number of individuals in a population at a specified time
B) number of individuals in a population at a specified place
C) number of individuals per unit area or per unit volume of habitat
D) size of the individual organisms per unit area
E) number of individual organisms per family unit

Question 20

Marine biologists tagged and released 50 marlin. Later, fishermen caught 300 marlin, 15 of which had tags. What is the estimate for the number of marlin in the population?

A) 5,000
B) 315
C) 365
D) 2,500
E) 1,000

Question 21

Type III survivorship curves reflect ____.

A) high juvenile mortality
B) low juvenile mortality
C) high survivorship
D) relatively constant mortality
E) high adult mortality

Question 22

Answer the question using the accompanying figure. A species with a relatively constant rate of mortality in all age classes would most likely exhibit which survivorship curve?

A) Type I, which is graph A
B) Type II, which is graph B
C) Type I, which is graph C
D) Type III, which is graph C
E) Type III, which is graph A

Question 23

An example of passive parental care is ____.

A) nutrients that cross the placenta
B) nursing
C) nurturing
D) the nest environment
E) protection from predators

Question 24

Life history patterns of guppies in Trinidad are a result of which natural selection force?

A) Competition differences in different streams.
B) Predation differences in different streams.
C) Temperature differences in different streams.
D) Pollution differences in different streams.
E) Salt concentration differences in different streams.

Question 25

The lifetime patterns of growth, maturation, and reproduction determine the ____ of a species.

A) survivorship curve
B) life history
C) specific mortality
D) age-specific fecundity
E) dispersion

Question 26

In the case of the red harvester ant, colonies that survive to ____ years of age are likely to contribute to the next generation of colonies.

A) one
B) three
C) four
D) seven
E) ten

Question 27

Organisms use ____ for maintenance, growth, and reproduction.

A) survivorship
B) predation
C) energy
D) parental care
E) dispersion

Question 28

Organisms store energy as ____.

A) starch only
B) glycogen only
C) fat only
D) sugar
E) starch, glycogen or fat

Question 29

In the construction of a life table for colonial species in which most organisms do not reproduce, ____ is/are considered as a reproductive individual.

A) each individual
B) clusters of individuals
C) the entire population in a geographical area
D) the entire population on Earth
E) each separate colony

Question 30

Which factor is responsible for reductions in population size?

A) immigration
B) death
C) birth
D) reproduction
E) dispersion

Question 31

In the equation ΔN/Δt = B - D, expressing deaths and births as per capita rates allows ecologists to _____.

A) apply the model to a population of any size
B) accurately measure births
C) accurately measure deaths
D) find the population growth rate
E) model geometric growth

Question 32

What is true of most deciduous trees in the temperate zone?

A) they spend all of their energy on reproduction
B) growth and reproduction occur simultaneously
C) they only produce one or two offspring annually
D) they produce thousands of seeds for one or two years
E) they only begin to breed after reaching adulthood

Question 33

Which characteristic is descriptive of a population experiencing geometric population growth?

A) population doubles in size after each generation
B) graph of the population growth produces a "J" shaped curve
C) per capita growth rate remains constant
D) ΔN/Δt is increasing
E) population increases at an increasing rate

Question 34

A population of 100 animals undergoing logistic growth has r_max= 0.4 and K = 102. Given that r = r_max(K - N)/K, calculate the value of r.

A) 0.0078
B) 0.792
C) - 0 . 5 80
D) 0.078
E) 0.99

Question 35

In the equation ΔN/Δt = B - D, B represents ____.

A) change in population size
B) time period
C) total births
D) total deaths
E) change in population size over time

Question 36

Answer the question using the accompanying figure. Humans living in environments with access to good medical care are most likely to exhibit which of the following survivorship curves?

A) Type I, which is graph A
B) Type II, which is graph B
C) Type I, which is graph C
D) Type III, which is graph C
E) Type III, which is graph A

Question 37

Fecundity is ____.

A) a summary of the demographic characteristics of a population
B) a group of individuals of similar age
C) the average number of offspring produced
D) the proportion of individuals alive at the start of an interval that die during that interval
E) the proportion of individuals alive at the start of an interval that survive to the start of the next interval

Question 38

What is the relationship between age-specific mortality and age-specific survivorship?

A) age-specific mortality is the proportion of individuals alive at the start of an age interval; age-specific survivorship is the proportion that die before the start of the next interval
B) age-specific survivorship is the proportion of individuals alive at the start of an age interval that die during the age interval; age-specific mortality is the proportion that survive until the start of the next interval
C) the sum of age-specific mortality and age-specific survivorship always equals 1
D) the sum of age-specific mortality and age-specific survivorship is always less than 1
E) age-specific survivorship is always greater than 1

Question 39

Mathematical models suggest that ____ will be favored by natural selection if organisms grow larger as they age.

A)   fecundity
B) iteroparity
C) delayed reproduction
D) early reproduction
E) semelparity

Question 40

Which organism's reproductive pattern exhibits semelparity?

A) grizzly bear
B) oak tree
C) red deer
D) salmon
E) maple tree

Question 41

Lizards can control spider populations on Caribbean islands by which density-dependent mechanism(s)?

A) predation only
B) competition only
C) predation on a common predator only
D) predation and competition
E) predation, competition, and predation on a common predator

Question 42

A(n) ____ is a group of neighboring populations that exchange individuals.

A) K -selected species
B) Type I species
C) r -selected species
D) sink population
E) metapopulation

Question 43

Crowding ____.

A) has a positive effect on reproduction
B) decreases the growth rate of individuals
C) only occurs in plant species
D) causes immigration
E) stimulates developmental and behavioral changes

Question 44

A time lag in the response of survivorship and fecundity to a population's density can occur because ____ is usually determined by the availability of resources at some time in the past.

A) death
B) immigration
C) fecundity
D) competition
E) population growth

Question 45

Carrying capacity is ____.

A) determined by the individuals of a species
B) defined for each population, and varies from one habitat to another
C) the same across all environments
D) the same in one habitat through time
E) the same across all populations

Question 46

The logistic model assumes that ____ will become increasingly limited as population grows larger.

A) deaths
B) births
C) immigration
D) competition
E) vital resources

Question 47

The transformation of humans from hunter-gatherer societies to agriculturally based ones occurred approximately ____.

A) 14,000 years ago
B) 11,000 years ago
C) 7,000 years ago
D) 1,500 years ago
E) 200 years ago

Question 48

What is an example of an extrinsic control of cycles in population size?

A) the relationship between a species and its predators
B) hormonal changes
C) dispersal
D) population density
E) a single reproductive event

Question 49

Intraspecific competition and predation are ____ factors.

A) crowding
B) density-dependent
C) reproductive
D) population
E) logistic

Question 50

Which statement characterizes human population growth?

A) The rate of human population growth appears to be declining.
B) The rate of human population growth appears to be increasing.
C) The rate of human population growth is exponential.
D) Human birth rates are higher than death rates.
E) Human death rates are higher than birth rates.

Question 51

A population's ____ occurs under ideal, unrealistic conditions.

A) per capita growth rate
B) per capita population curve
C) intrinsic rate of increase
D) geometric population curve
E) exponential population curve

Question 52

Studies have determined that ____ is not responsible for the cyclical rise and fall of arctic hare and lynx populations.

A) predation
B) a limited food supply for hares
C) predation by other mammals
D) intraspecies competition
E) disease

Question 53

For the bay checkerspot butterfly, a poor flyer, to recolonize small patch habitats, the new habitats must be ____.

A) high quality
B) low quality
C) close to a source population
D) far from a source population
E) above a certain number of individuals

Question 54

The increased mortality of coniferous trees in the Pacific Northwest between 1955 and 2007 is an example of a reaction to ____.

A) density-independent factors
B) density-dependent factors
C) predation
D) crowding
E) population growth

Question 55

The intrinsic rate of increase is ____ for bacteria, protists, and animals with short generation times and ____ for those with long generation time.

A) high; low
B) high; constant
C) low; high
D) low; constant
E) constant; low

Question 56

The success of human populations resulted from ____.

A) their ability to solve ecological problems
B) a stable climate
C) their society
D) their hunting ability
E) absence of predators

Question 57

The beginning of the industrial and scientific revolution occurred ____.

A) when human population size was approximately one billion
B) when human population size was approximately one million
C) when human population size was approximately five million
D) approximately 500 years ago
E) approximately 100 years ago

Question 58

Which trait is characteristic of a K -selected species?

A) adapted to rapidly changing environments
B) small body size
C) short generation time
D) provide substantial parental care to offspring
E) single reproductive event

Question 59

In the logistic model of population growth, what is expected to happen to r when N = K? r will approach 1

A) r will approach r_max
B)   r will approach 1
C) r becomes negative
D) r = 0
E) r>0

Question 60

The difference between the per capita birth rate and the per capita death rate is the ____.

A) per capita growth rate
B) per capita population curve
C) intrinsic rate of increase
D) geometric population curve
E) exponential population curve

Question 61

The sum total of all the resources we use is called the ____.

A) demographic transition model
B) age-structure diagram
C) habitat
D) ecological footprint
E) transitional age

Question 62

A human population with an age structure diagram that is narrower at the base than at the top would have ____.

A) zero population growth
B) r
C) r>0
D) been affected by density independent factors
E) (K - N)/K

Question 67

The postindustrial age is defined by ____.

A) high birth and death rates
B) zero population growth
C) dramatic slowing in population growth
D) declining death rate
E) declining birth rate

Question 69

What are some density-dependent factors that affect humans at higher population densities? How have these been addressed in industrial societies?

Question 70

A human population living without medical care in a developing country would probably have ____.

A) a rectangle-shaped age structure diagram
B) an r value
C) a pyramid-shaped age structure diagram
D) per capita birth and death rates consistent with those of a stage 4 society
E) no density-dependent factors operating

Question 71

According to the text, humans have two options for limiting population growth: 1) make a global effort to limit our own population, or 2) can wait until the environment does it for us. Briefly address each scenario. Which methods would result in a successful global decline in birthrate? Which environmental events are the alternatives?

Question 72

Answer the question using the accompanying figure. The letter "A" represents ____.

A) rapid growth
B) negative growth
C) prereproductive populations
D) postreproductive populations
E) zero growth

Question 73

Birth rates generally reach their highest point in which stage of a country's demographic transition?

A) preindustrial
B) transitional
C) industrial
D) postindustrial
E) stage 1

Question 74

Recent studies have demonstrated evolution in some populations over a span of time as short as ____.

A) single years
B) decades
C) centuries
D) thousands of years
E) millions of years

Question 75

Uniform dispersion usually results from individuals of a species repelling each other.

Question 76

Which phenotypic effects does crowding have on the migratory locust? How are these changes adaptive?

Question 77

Answer the question using the accompanying figure. Rapid population growth is represented by the letter ____.

A) A
B) B
C) C
D) D
E) E

Question 78

How are an organism's lifetime energy use and economics analogous?

Question 79

Research has shown that commercial fisheries place selective pressure on fish populations by harvesting mostly the ____ fish, resulting in ____.

A) young; aging populations
B) larger; maturity at smaller sizes
C) smaller; maturity at larger sizes
D) prereproductive; declining birth rates
E) postreproductive; no change in population size

Question 80

A stage 3 society, based on the demographic transition model, would not be characterized by ____.

A) an r value>0
B) industrialization
C) a clumped population distribution
D) (K - N)/K approaching 1
E) an r value approaching 1