Chapter 16: Population Ecology

Question 1

Populations that exhibit logistic growth still exhibit exponential growth. This statement is:

1. true; logistic growth is another term for exponential growth.
2. true; however, this can only occur in different populations of the same organism because one population cannot exhibit both types of growth.
3. false; exponential growth and logistic growth are characteristics of different species.
4. true; populations exhibiting logistic growth go through a period of exponential growth before growth rates level off as N approaches K.
5. false; populations exhibiting logistic growth show exponential growth when the population size is greater than the environment’s carrying capacity.

Answer 1

true; populations exhibiting logistic growth go through a period of exponential growth before growth rates level off as N approaches K

Question 2

A population pyramid that gets wider in shape with higher age groups represents _____ while a population pyramid with nearly parallel lines represents _____.

1. declining growth; stationary (zero) growth
2. declining growth; increasing growth
3. increasing growth; stationary growth
4. increasing growth; declining growth
5. stationary growth; increasing growth

Answer 2

declining growth; stationary (zero) growth

Question 3

A population of meadow voles has an annual per capita birth rate of 0.08 and an annual per capita death rate of 0.02. Estimate the number of individuals added to or lost from a population of 1,000 individuals in 1 year.

1. 60 individuals added
2. 120 individuals added
3. 20 individuals lost
4. 20 individuals added
5. 400 individuals added

Answer 3

60 individuals added

Question 4

What might happen when a population exceeds its carrying capacity?

1. The population will decline until it reaches its carrying capacity and fluctuate at about that number.
2. The carrying capacity will increase.
3. The level of resources in the habitat will increase equally.
4. The population may shoot past its carrying capacity hold that population size that exceeds its carrying capacity.

Answer 4

The population will decline until it reaches its carrying capacity and fluctuate at about that number

Question 5

Which type of effect has an increasing impact as the population size increases?

1. Coriolis
2. density-dependent
3. density-independent
4. mortality

5, survivorship

Answer 5

density-dependent

Question 6

A population pyramid with a more rectangular shape:

1. describes all population pyramids, as the graphs provide data for only 1 year.
2. reflects data for only one sex as opposed to both.
3. reflects unchanging birth and death rate patterns.
4. is a common shape for developing countries.
5. has the shape of an inverted pyramid.

Answer 6

reflects unchanging birth and death rate patterns

Question 7

Mutations that cause sickness and death after reproduction:

1. are passed on to future generations only in species that have short life spans.
2. can be passed on to future generations.
3. will not be passed on to future generations.
4. are unlikely to occur.
5. are passed on to future generations only in species that have long life spans.

Answer 7

can be passed on to future generations

Question 8

The graph represents the standard demographic transition—the pattern of population growth that occurs as a country industrializes. In this graph, the green line represents __________________, the red line represents __________________, and the blue curve represents _________________.
image

1. birth rate; death rate; population growth rate
2. death rate; birth rate; population growth rate
3. death rate; birth rate; total population size
4. birth rate; death rate; total population size
5. population growth rate; carrying capacity; total population size

Answer 8

birth rate; death rate; population growth rate

Question 9

In a population, as N approaches K, the logistic growth equation predicts that:

1. the growth rate will not change.
2. the carrying capacity of the environment will increase.
3. the population will become monophyletic.
4. the growth rate will approach zero.
5. the population size will increase exponentially.

Answer 9

the growth rate will approach zero

Question 10

After studying the two population pyramids below, decide which of the following statements regarding the diagrams is TRUE.
image

1. Population R is larger than Population S.
2. Population R is growing at a slower rate than Population S.
3. The death rate in Population R is lower than in Population S.
4. Individuals in Population R begin reproducing at an earlier age than those in Population S

Answer 10

Population R is growing at a slower rate than Population S

Question 11

The demographic transition:

1. is not influenced by the quality of health care available to a population.
2. includes a decrease in the death rate followed by a decrease in the birth rate as a population becomes industrialized.
3. is characterized by an increase in a population’s growth rate.
4. occurs in predator–prey pairs, such as the lynx and hare, whose population sizes cycle regularly.
5. includes a decrease in the birth rate followed by a decrease in the death rate as a population becomes industrialized.

Answer 11

includes a decrease in the death rate followed by a decrease in the birth rate as a population becomes industrialized

Question 12

Life histories are based on:

1. the rate of growth and development.
2. the age at death.
3. the age of reproduction and the number of reproductive events.
4. the amount of energy available to an individual at birth.
5. All of the above are the bases for life histories.

Answer 12

All of the above are the bases for life histories

Question 13

In the graph, curve A is the ____________________ and curve B is the ___________________.
image

1. logistic growth curve; exponential growth curve
2. logistic growth curve; maximum sustainable yield
3. logistic growth curve; carrying capacity
4. carrying capacity; logistic growth curve
5. exponential growth curve; logistic growth curve

Answer 13

exponential growth curve; logistic growth curve

Question 14

A species most likely to exhibit the Type II survivorship curve depicted below would be:
image

1. mackerel.
2. giant tortoises.
3. blue jays.
4. fruit flies.
5. humans.

Answer 14

blue jays

Question 15

A life history of an organism does NOT consist of the organism’s:

1. reproduction.
2. death.
3. birth.
4. growth to maturity.
5. None of the above; all are part of an organism’s life history.

Answer 15

None of the above; all are part of an organism’s life history

Question 16

The death rate of organisms in a population exhibiting a Type III survivorship curve is:

1. higher in postreproductive than in prereproductive years.
2. usually correlated with disease.
3. more or less constant throughout their lives.
4. usually correlated with density-independent causes.
5. initially high but lower after the organisms survive the first few age intervals.

Answer 16

initially high but lower after the organisms survive the first few age intervals.

Question 17

In the equation for logistic growth, when N = K:

1. population growth rate is declining, though the population itself is still increasing.
2. population growth is negative.
3. the population has exceeded carrying capacity.
4. population growth is positive.
5. population growth stops.

Answer 17

population growth stops

Question 18

A primary difference in the age pyramids of industrialized versus developing countries is that:

1. mean longevity is significantly greater among third-world countries.
2. third-world countries have significantly more individuals than industrialized countries.
3. third-world countries have much larger proportions of their population in the youngest age group.
4. in third-world countries females live significantly longer than men, whereas in industrial countries the reverse is true.
5. third-world countries show a characteristic “bulge” that indicates a baby boom.

Answer 18

third-world countries have much larger proportions of their population in the youngest age group

Question 19

A Type III survivorship curve would be expected in a species in which:

1. mortality rate is quite low for the young.
2. mortality occurs at a constant rate over the lifespan.
3. biparental care is necessary.
4. parental care is extensive.
5. a large number of offspring are produced but parental care is minimal.

Answer 19

a large number of offspring are produced but parental care is minimal

Question 20

Organisms with slow development and a high investment in their young will most likely have a __________ survivorship curve.

1. Type II–Type III hybrid
2. Type III
3. Type I

4.Type II

5. Type I–Type II hybrid

Answer 20

Type I