Deck 42: Populations

Question 1

If the survivorship of a sample of geese is 0.75 for the month of March,what is the fecundity of this sample?

A) 0.25
B) 0.375
C) 0.75
D) 1
E) The answer cannot be determined from the data given.

Answer 1

E

Question 2

Which factor would be most conducive to counting all of the individuals in a population instead of taking a sample?

A) Small body size of the individuals in the population
B) Relatively stationary individuals
C) A large population
D) Difficulty distinguishing the boundaries of individuals
E) Rapidly moving individuals

Answer 2

B

Question 3

If four hundred robins are found in a ten-hectare plot,the density of robins in that plot is _______ robins/ha.

A) 10
B) 14
C) 40
D) 400
E) 4,000

Answer 3

C

Question 4

What is the per capita rate of increase for that day?

A) -0.02
B) 0
C) 0.02
D) 0.04
E) 0.06

Question 5

The population densities of skunks in western Massachusetts vary considerably from year to year;therefore,skunk density is

A) at equilibrium.
B) density dependent.
C) dynamic.
D) a metapopulation.
E) at carrying capacity.

Question 6

If the per capita birth rate of 360 shrubs is 0.05 and the per capita death rate is 0.02,the per capita growth rate is

A) negative.
B) 0.03.
C) 0.05.
D) 0.07.
E) 18.

Question 7

Which is a major assumption of the BD model of population change?

A) Populations always grow.
B) Populations are limited by a fixed carrying capacity.
C) Once an organism has acquired a unit of some resource,this resource can be used for only one function at a time.
D) Individuals do not move into or out of the population.
E) Population growth is density dependent.

Question 8

Which statement about life histories is false?

A) They are quantitative descriptions of life cycles.
B) They include the time course of growth and development.
C) They include the time course of reproduction.
D) Information about life histories can be summarized in a life table.
E) Life histories do not vary within a single species.

Question 9

If a total of 2,400 oak trees are counted in a 6 km × 2 km rectangular patch of land,the density of the oak trees is _______ per square km.

A) 24
B) 48
C) 96
D) 120
E) 200

Question 10

Suppose there are three geographically separated populations of moose in Maine.Population A has a population size of 870 and a per capita growth rate of -0.06 per month.Population B has a population size of 456 and a per capita growth rate of 0.02 per month.Population C has a population size of 1,426 and a per capita growth rate of 0.12 per month.Assuming that the per capita growth rates remain constant,which population is at risk of extinction?

A) Population A only
B) Population B only
C) Population C only
D) Both populations A and B
E) Both populations B and C

Question 11

For which population would biologists most likely measure population density in terms of number per unit of volume rather than number per unit of area?

A) Guppies in a lake
B) Mice in a patch of grassland
C) Pine trees in a forest
D) Squirrels on a campus
E) Oak seedlings in a backyard

Question 12

The number of individuals in a population divided by the area that the population takes up is known as the _______ of the population.

A) density
B) demography
C) structure
D) dispersion
E) dynamics

Question 13

Suppose you are in an area where Lyme disease is prevalent.There is a decrease in the size of the acorn crop.This change will most likely lead to a(n)_______ in the incidence of Lyme disease because there is a decrease in the size of _______ populations.

A) increase;deer
B) increase;rodent
C) increase;bird
D) decrease;rodent
E) decrease;deer

Question 14

One reason that apple maggot flies are distributed in patches is that they feed off of apple,hawthorn,and other similar trees,which themselves are not evenly distributed.These trees represent _______ for the flies.

A) homeostasis
B) equilibria
C) metapopulations
D) corridors
E) habitats

Question 15

Suppose the population density of a sample of a bagworm population is 45 per square meter.Assuming that the population is uniformly distributed,what would be the population size if the bagworms encompassed an area that was 1 km × 200 m?

A) 200,000
B) 900,000
C) 9 million
D) 20 million
E) 90 million

Question 16

Use the following to answer questions :
In a population of 1,250 aphids,50 died on a particular day,while 25 were born.
What is the per capita death rate for that day?

A) 0.02
B) 0.04
C) 0.05
D) 0.06
E) 0.08

Question 17

The agent that causes Lyme disease is a

A) bacterium.
B) virus.
C) tick.
D) fungus.
E) protist.

Question 18

The per capita growth rate of a population of guppies is 0.07 per month.If the per capita birth rate is 0.12 per month,the per capita death rate is _______ per month.

A) -0.19
B) -0.05
C) 0.05
D) 0.12
E) 0.19

Question 19

Assume that a population of marmots fits the BD model,with no movement into or out of the population.If 245 individuals are in the population at the start of the month,43 die during the month,and 37 are born during the month,what is the population size of the marmots at the end of the month?

A) 202
B) 239
C) 251
D) 282
E) 325

Question 20

Use the following to answer questions :
In a population of 400 gray foxes,the per capita birth rate in a particular time period is 0.07 and the per capita death rate is 0.14.
The per capita growth rate of this population is

A) negative.
B) 0.07.
C) 0.14.
D) 0.21.
E) 28.

Question 21

If the survivorship at the start of October is 0.4,what is the mortality rate during the month of September?

A) 0.15
B) 0.20
C) 0.30
D) 0.50
E) 0.80

Question 22

The principle of _______ explains why growth and reproduction rates are usually _______ correlated.

A) homeostasis;positively
B) homeostasis;negatively
C) allocation;positively
D) allocation;negatively
E) the carrying capacity;positively

Question 23

Use the following to answer questions :
Refer to the figure below.
Under which conditions can both the rice weevil and the lesser grain borer persist indefinitely?

A) 10°C and 10% moisture
B) 10°C and 14% moisture
C) 20°C and 10% moisture
D) 30°C and 10% moisture
E) 30°C and 14% moisture

Question 24

Use the following to answer questions :
Suppose that of a sample of 300 mice in a mouse colony born in January,150 are still alive at the start of September.
What is the survivorship up to the start of September?

A) 0.15
B) 0.30
C) 0.45
D) 0.50
E) 0.60

Question 25

Compared with the Turkana of East Africa,people in the United States have a _______ life expectancy and enter puberty at _______ age.

A) greater;a later
B) greater;about the same
C) greater;an earlier
D) lower;a later
E) lower;an earlier

Question 26

Which event is a life-history trade-off?

A) A mutation in a nematode reduces both survivorship to a given age and fecundity.
B) Strains of Drosophila melanogaster that reproduce early do not live very long.
C) Stress causes mice to allocate more resources to maintaining proper balance of metabolites.
D) Stress reduces fecundity in mice.
E) Baboon populations that are well nourished have a higher rate of population growth than those that are not.

Question 27

If the survivorship at the start of October is 0.4,how many mice died during the month of September?

A) 10
B) 16
C) 30
D) 72
E) 90

Question 28

Each month,the per capita birth rate of a population is b,and the per capita death rate is d.The initial size of the population is N.Assuming that the birth and death rates remain constant,what formula represents the population size after five months? [Hint: Think about how populations increase,and generate a formula based on that knowledge.]

A) N × (b - d)
B) N × 5(b - d)
C) N × (b - d)⁵
D) N × (1 + b - d)
E) N × (1 + b - d)⁵

Question 29

Under which conditions can the lesser grain borer persist indefinitely,but the rice weevil cannot persist?

A) 10°C and 10% moisture
B) 10°C and 14% moisture
C) 20°C and 10% moisture
D) 30°C and 10% moisture
E) 30°C and 14% moisture

Question 30

Which change is most likely to increase r?

A) A decrease in survivorship at a given age
B) An increase in the mortality at a given age
C) A decrease in fecundity at a given age
D) Reproduction switching to older individuals
E) Reproduction switching to younger individuals

Question 31

The relationship between the rate at which kangaroo rats can harvest seeds and the seed density best illustrates

A) the principle of allocation.
B) that resource acquisition increases with resource availability.
C) the diversity of life history traits.
D) that life histories are quantitative descriptions of life cycles.
E) the BD model of population change.

Question 32

A rodent species that once experienced much predation now has lower predation risk.As a consequence,the mortality of maturing individuals is reduced.What will be the most likely response to a reduction in mortality?

A) A shift to later reproduction with the benefit of higher fecundity,because individuals are larger
B) A shift to later reproduction at the expense of lower fecundity,because individuals are smaller
C) A shift to earlier reproduction at the expense of lower fecundity,because individuals are smaller
D) A shift to later reproduction with the benefit of higher fecundity,because individuals are smaller
E) A shift to earlier reproduction at the expense of lower fecundity,because individuals are larger

Question 33

Which item does not constitute a resource for a rodent?

A) Calcium for bone growth
B) Energy stored in an apple
C) High temperature experienced in the desert
D) Time spent acquiring other resources
E) Space for a nest

Question 34

An increase in rainfall brings more plant resources to a population of lizards,but it also brings more predators.These changes result in both an increase in fecundity and a decrease in survivorship.Under these conditions,which event is most likely?

A) The per capita birth rate of the population will increase.
B) The per capita rate of growth of the population will be above zero.
C) The per capita rate of growth will increase.
D) Reproduction switching to older individuals
E) Both a and b

Question 35

In resource allocation,the needs of _______ generally must be taken care of before resources can be devoted to other activities.

A) growth
B) reproduction
C) fecundity
D) defense
E) maintenance

Question 36

What is the fundamental distinction between resources and physical conditions?

A) Resources can be used up,but conditions cannot.
B) Conditions can be used up,but resources cannot.
C) Favorable resources can lead to higher fecundity rates,but favorable conditions cannot.
D) Favorable conditions can lead to higher fecundity rates,but favorable resources cannot.
E) The term "resources" is used when talking about the needs of animals,while the term "conditions" is used when talking about the needs of plants.

Question 37

The pH in a fish tank decreases.Although there is no change in the amount of resources and predation is minimal,the more acidic conditions are stressful to minnows.What will most likely happen?

A) The population growth rate will increase.
B) The fish will allocate more resources to defense.
C) The fish will allocate more resources to maintenance.
D) The fish will allocate more resources to growth.
E) Life expectancy will increase.

Question 38

If a certain age interval in a population contains ten individuals and has a mortality rate of 1.00,how many individuals will be in the next older age interval?

A) 0
B) 1
C) 5
D) 9
E) 10

Question 39

Which statement about population growth is true?

A) If the per capita birth rate and the death rate remain constant,the population will grow additively.
B) A population growing additively will not have a consistent doubling time.
C) With additive growth,populations generate large numbers much more quickly than they do with multiplicative growth.
D) The series 10,15,20,25,30,35 represents multiplicative growth.
E) The series 1,2,4,8,16,32,64 represents additive growth.

Question 40

Assuming constant rates,which population could persist indefinitely?

A) One with a per capita growth rate of ‒0.02
B) One with a per capita birth rate of 0.05 and a per capita death rate of 0.07
C) One with a per capita birth rate of 0.13 and a per capita death rate of 0.16
D) One with a per capita birth rate of 0.11 and a per capita death rate of 0.07
E) None of the above

Question 41

Which factor would most likely limit the size of a population?

A) An increase in the population growth rate as density increases
B) A decrease in the population growth rate as density increases
C) A decrease in mortality as density increases
D) Multiplicative growth
E) Additive growth

Question 42

Which observation best supports the argument that that human population of the Earth is still below its long-term carrying capacity?

A) Climate change is occurring.
B) Marine ecosystems are being degraded.
C) Freshwater ecosystems are being degraded.
D) Wind and other renewable sources of energy are replacing fossil fuels.
E) Maintaining current levels of agricultural production depends on fertilizers derived from natural gas.

Question 43

At the beginning of May,259 butterflies are found in a certain locality.During the month,45 butterflies emigrate,10 die,and 67 immigrate into the area.There are no butterfly births.What is the population size at the end of the month?

A) 192
B) 249
C) 271
D) 281
E) 346

Question 44

The human population size is expected to be about _______ in the year 2025.

A) 800 million
B) 2 billion
C) 5 billion
D) 8 billion
E) 20 billion

Question 45

The current per capita annual growth rate for the human population is about _______ percent.

A) -2.2
B) -1.1
C) 1.1
D) 2.2
E) 22

Question 46

The doubling time of a population of annual plants is 14 years.Assuming that the initial size of the population is 500 and that the rate of increase remains constant,how large will the population be after 42 years?

A) 1,000
B) 1,500
C) 2,000
D) 4,000
E) 8,000

Question 47

A BIDE model of population growth is more applicable than a BD model for a population

A) that follows multiplicative growth.
B) that is shrinking.
C) that is part of a metapopulation.
D) in which reproduction occurs at regular intervals.
E) in which reproduction occurs at irregular intervals.

Question 48

A captive population of monkeys made up of 130 individuals in the year 1966 has a size of 520 in the year 2010.Assuming that the rate of population growth was constant,the doubling time of this population was _______ years.

A) 11
B) 15
C) 22
D) 44
E) 88

Question 49

The rate at which the world's population is increasing is slowing because

A) birth rates have declined more quickly than death rates have declined.
B) the long-term carrying capacity of Earth is increasing.
C) the long-term carrying capacity of Earth is decreasing.
D) death rates have increased more quickly than birth rates have increased.
E) of climate change.

Question 50

In the study of cactus finches in the Galápagos,the most important environmental factor influencing survival rate was discovered to be

A) rainfall.
B) temperature.
C) parasites.
D) predation.
E) tick abundance.

Question 51

Use the following to answer questions :
Populations of a certain yeast strain grow according to a simple form of logistic growth in which r declines linearly with population density.Suppose that the rate of increase is 0.04 per day when density is very low and the rate of increase is 0.02 per day when the density is 15,000 per cubic centimeter.
What is the rate of growth at the carrying capacity?

A) -0.04
B) 0
C) 0.02
D) 0.04
E) It cannot be determined.

Question 52

The larger population that is composed of many subpopulations is known as a

A) habitat patch.
B) habitat corridor.
C) megapopulation.
D) population structure.
E) metapopulation.

Question 53

Which condition would not cause population growth to be density dependent?

A) An unexpected drought that kills plant seedlings
B) An increase in the incidence of malaria as populations increase
C) A limited number of suitable nest sites for a particular bird species in a particular area
D) Large aggregations of guppies that attract predators
E) Stress in mice caused by crowding,leading them to devote fewer resources to reproduction

Question 54

What is the approximate carrying capacity (per cubic centimeter)?

A) 7,500
B) 15,000
C) 30,000
D) 60,000
E) 90,000

Question 55

Eighty-one pocket gophers were present in Maddox Field at the start of 2006.During that year,24 individuals were born and 19 died.Twelve individuals immigrated and 10 emigrated.How many pocket gophers were present in Maddox Field at the start of 2007?

A) 76
B) 81
C) 86
D) 88
E) 146

Question 56

According to Malthus,the food supply for humans increases _______,but the population grows _______.

A) logistically;multiplicatively
B) logistically;additively
C) multiplicatively;additively
D) multiplicatively;logistically
E) additively;multiplicatively

Question 57

Which statement is best supported by the relationship between acorn abundance and tick population size?

A) Populations growing multiplicatively with constant r have a constant doubling time.
B) The carrying capacity of a population is an unalterable constant.
C) The tick population is a closed system.
D) The tick population is an open system.
E) Carrying capacity can change with changing conditions.

Question 58

Which factor is most likely to cause an increase in the carrying capacity of a population?

A) An increase in food supply
B) An increase in the potential birth rate
C) An increase in the resource requirement per individual
D) An increase in stress
E) An increase in predation

Question 59

Which statement about carrying capacity (K)is true?

A) When N = K,the birth rate in a population is necessarily zero.
B) The rate of population growth in an unlimited environment is proportional to K.
C) At K,the population must have a negative growth rate.
D) At K,the population must have a positive growth rate.
E) In a population at its K,the birth rate equals the death rate.

Question 60

Approximately how long did it take the human population to grow from 1 billion to 2 billion?

A) Between 10 and 20 years
B) Between 100 and 200 years
C) Between 300 and 500 years
D) Between 1,000 and 2,000 years
E) More than 2,000 years

Question 61

Which statement about subpopulations within metapopulations is false?

A) Compared to larger subpopulations,smaller subpopulations have a greater risk of going extinct due to environmental disturbances.
B) Compared to larger subpopulations,smaller subpopulations have a greater risk of going extinct because of chance factors.
C) Dispersal between subpopulations can increase the length of time during which a metapopulation can persist.
D) If the patch habitat is favorable,extinction of a small subpopulation is highly unlikely.
E) A subpopulation that exchanges migrants is an open system.

Question 62

Which statement about demography models is true?

A) The BIDE model is more appropriate for a closed system than for an open system.
B) The BD model is more appropriate for an open system than for a closed system.
C) The BD model is more appropriate than the BIDE model for modeling metapopulations.
D) The BIDE model is more appropriate than the BD model for modeling metapopulations.
E) Subpopulations within a metapopulation must be closed systems.

Question 63

An increase in the amount of serpentine soil in the region where Edith's checkerspot butterflies are found would likely lead to a(n)_______ in the population of this butterfly because _______ in serpentine soil.

A) increase;their predators cannot live
B) increase;fewer parasites are found
C) increase;their food source is found only
D) decrease;their host plants do not perform well
E) decrease;their competitors thrive

Question 64

In what way are rockfish and the ticks that cause Lyme disease most similar?

A) Both provision their young with oily droplets.
B) In both species,relatively few egg-laying adults are required to maintain the population.
C) Humans are trying to increase the population sizes of both species.
D) Humans are trying to decrease the population sizes of both species.
E) Both transmit diseases to humans.

Question 65

Births,deaths,and other processes that add to or subtract from populations are all considered _______ events.

Question 66

The primary feeding source of adult black-legged ticks is

A) deer.
B) rodents.
C) birds.
D) humans.
E) acorns.

Question 67

No-fishing areas help maintain populations of the rockfish Sebastes melanops because these areas

A) increase dispersal rates between subpopulations.
B) allow some females to grow large.
C) allow some males to grow large.
D) reduce disease risk.
E) keep fish small.

Question 68

For conservation purposes,a continuous corridor of habitat would be least needed for a species

A) with low dispersal ability.
B) with a low birth rate.
C) that can fly.
D) with a metapopulation structure.
E) that is wingless.

Question 69

You are managing a metapopulation of a threatened beetle that lives on a plant that is found in patches.Because of the distribution of its host plant,the beetle is also found in patches,and these patches vary in size.If you are faced with limited resources and cannot attempt to save all of the beetle subpopulations,where should you concentrate your efforts,and why?

A) On the smallest patches,because these are at highest risk for extinction
B) On the smallest patches,because subpopulations in these patches will have the highest growth rates
C) On the smallest patches,because these have the lowest likelihood of being affected by environmental disturbances
D) On the largest patches,because these have the highest potential to reseed the other patches
E) On whichever patches are most convenient,because patch size does not matter

Question 70

In order to determine population density,a researcher _______ the number of individuals in the population by the area of the space covered by the population.

Question 71

The primary feeding source of black-legged tick larvae is

A) deer.
B) rodents.
C) birds.
D) acorns.
E) adult ticks.

Question 72

Based on what you have read about metapopulation dynamics in Edith's checkerspot butterflies,which statement is most likely to be true?

A) Large subpopulations are more likely to go extinct than smaller ones.
B) Patches near occupied patches can be colonized more readily than ones farther away.
C) Once extinct,a subpopulation can never be reestablished.
D) The butterfly flourishes during severe droughts.
E) The BD model captures the population dynamics of Edith's checkerspot butterflies better than the BIDE model.

Question 73

In the BIDE model of population growth,the "E" stands for

A) ecology.
B) emigration.
C) extinction.
D) environmental.
E) evolutionary.

Question 74

To reduce the incidence of Lyme disease,the most important factor is to control the population size of _______,because this in turn reduces the number of larval ticks that _______.

A) deer;hatch from eggs
B) deer;find blood meals
C) rodents;hatch from eggs
D) rodents;find blood meals
E) cattle;hatch from eggs

Question 75

Which statement about the rockfish Sebastes melanops is false?

A) They grow continuously throughout their lives.
B) The larger females can produce the most eggs at any given time.
C) The larger females are the most able to provision eggs with resources.
D) Better provisioned young grow and survive better than those that are less well provisioned.
E) The smaller females can produce as many eggs as the larger females,but the eggs are smaller.

Question 76

One reason that many butterflies are distributed in patches is that they feed on particular species of plants which themselves are not evenly distributed.These plants represent _______ for the butterflies.

Question 77

Which statement best describes an important distinction between the BD model and the BIDE model?

A) In the BIDE model,once the density equals zero,it remains at zero.In the BD model,density can go from zero to non-zero.
B) In the BD model,birth rates can never be less than zero.In the BIDE model,the birth rate can be less than zero.
C) In the BIDE model,birth rates can never be less than zero.In the BD model,the birth rate can be less than zero.
D) In the BD model,death rates can never be less than zero.In the BIDE model,the death rate can be less than zero.
E) In the BD model,once the density equals zero,it remains at zero.In the BIDE model,density can go from zero to non-zero.

Question 78

Which statement about habitat corridors is true?

A) They are places where an endangered species can live and breed.
B) They are usually used in captive breeding studies.
C) They exacerbate the deleterious effects of habitat fragmentation.
D) They are most effective as a conservation measure for species that disperse little.
E) Their presence can mitigate the deleterious effects of habitat fragmentation.