BIOL CH36

The age structure of the United States in 2015

shows that a greater proportion of the population is elderly now than in earlier decades.

Which statement about the application of insecticides is true?

Pest species can rebound faster than their predators because the pests often have a higher reproductive rate than predators have

Which of the following is the most accurate comment on the Earth's carrying capacity for people?

Our technology has allowed us to keep increasing K.

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

uniform dispersion

An important reason that human birth rates today far outstrip death rates in developed countries is __________.

increased health care.

Which of the following would likely decrease the Earth's human carrying capacity?

increasing meat production

Which of the following is regarded as a density-dependent factor in the growth of natural populations?

intraspecific competition

An oak tree produces thousands of acorns, but very few grow into mature oak trees. The oak tree exhibits a __________ survivorship curve.

type III

Which is a practical application of population ecology that will result in population decline?

removing habitat space from wild animal populations

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 1 year?

330

Which statement about human demographic trends is true?

A human population in which women reproduce at a later age will experience slower population growth.

Which of the following best illustrates a feature of K-selection?

A mother elephant spends several years protecting her baby.

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?

An increase in the owl population should cause a fall in the rabbit population

Which statement about human population growth is true?

Demographic transition is a transition from high birth rates and high death rates to low birth rates and low death rates.

What is meant by the term ecological footprint?

It is the amount of land and water area required to support a single individual.

What kind of curve represents exponential growth?

J-shaped

Which of the following describes the distribution of survivorship or mortality for a population that has a Type II survivorship curve?

The chance of death is roughly constant over all ages.

Which of the following situations would most likely lead to a uniform distribution of organisms?

The distribution of male beta fish defending their territories

Which example is most clearly a case of density-dependent population regulation?

a dangerous new flu strain that is transmitted among humans by sneezing

Biologists studying red-tailed hawks in eastern Kentucky discovered that the hawks mainly ate squirrels. We would expect that _____.

a decrease in the food supply of squirrels in this region would result in a decline in the red-tailed hawk population

The death by bubonic plague of about one-third of Europe's population during the 14th century is a good example of

a density-dependent effect.

A survivorship curve is a graph that plots

an individual's likelihood of being alive as a function of age.

The maximum number of individuals a habitat can support is called its

carrying capacity

The number of individuals that a particular habitat can support with no degradation of the habitat is called _____.

carrying capacity

In wild populations, individuals most often are found near available resources and show a _____ pattern of dispersion.

clumped

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

clumped

Which action will likely decrease a population's size?

decreasing the food supply available to the population

Assume that there are five alligators per acre in a swamp in northern Florida. This is a measure of the alligator population's

density

A bluegill population is at its carrying capacity in a stable lake in Minnesota. Biologists studying the bluegills' reproductive behavior learn that a single female in one breeding season can produce 1,000 to 70,000 eggs. We can expect that the life table of these Minnesota bluegills will indicate __________.

high early mortality in a Type III survivorship curve

A survivorship curve that shows a population producing very few offspring, each of which has a high probability of surviving to adulthood, is typical of

elephants

At carrying capacity, a population __________.

fluctuates around a median number

A broad-based pyramid-shaped age structure is characteristic of a population that is _____.

going rapidly.

An r-selected species typically

has an advantage in habitats that experience unpredictable disturbances

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?

logistic

Which of the following increases human population growth?

medical advances that decrease infant mortality

In the models that describe population growth, r stands for __________.

per capita rate of increase

What type of population will most readily recover from efforts to eradicate it?

r-selected

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

size will decrease.

Which activity would result in a decrease in your ecological footprint?

taking a city bus instead of driving to work

Which of the following represents an example of a population?

the eastern gray squirrels that live in New York City's Central Park

Which of the following is the best example of a density-independent factor limiting population size?

the frequency of rainfall needed for the germination of desert plant seeds

What is the age structure of a population?

the number of individuals alive in different age-groups at one time point

Which statement is a correct statement of human populations?

the world as a whole is undergoing a demographic transition in which there is a shift from high birth and high death rates to low birth and low death rates`

You represent a timber company that specializes in Douglas fir trees. You manage 10,000 acres for the company. On this property are mostly mature Douglas firs 200 to 300 years old. However, productivity of Douglas fir trees peaks between 60 and 90 years of age. Past studies have indicated that Douglas fir trees follow the logistic growth model. Which of the following will likely decrease your timber harvest over the next 50 years?

waiting to harvest trees in their most mature stages of growth, when they are over 200 years old

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

whether the owl eat the rabbits.