PCB 3043 Chapter 12

Scientists spent 10 years measuring population parameters in gray squirrels in North Carolina. For each age class, x, they measures the number of individuals, nx, survivorship, lx, and fecundity, bx, of this population of squirrels. The data are shown in the table. The generation time, T, for these data is 2.68, and the net reproduction rate, R0, is 1.17. Calculate the intrinsic growth rate, λa, from these data. -1.55 -9.57 -1.06 3.13

-1.06

Scientists spent 10 years measuring population parameters in gray squirrels in North Carolina. For each age class, x, they measures the number of individuals, nx, survivorship, lx, and fecundity, bx, of this population of squirrels. The data are shown in the table. Calculate the net reproductive rate, R0, from these data. -3.13 -1.17 -530 -2.28

-1.17

Scientists spent 10 years measuring population parameters in gray squirrels in North Carolina. For each age class, x, they measures the number of individuals, nx, survivorship, lx, and fecundity, bx, of this population of squirrels. The data are shown in the table. Calculate the generation time, T, from these data. -1.17 -2.67 -3.13 -1.55

-2.67

Which of the following factors would determine the carrying capacity for a population? -A limited amount of habitat area for a territorial species. -Too few individuals in the population. -A low death rate. -A low birth rate.

-A limited amount of habitat area for a territorial species.

Select the definition of net reproductive rate. -The average number of offspring an individual produces in a year. -The total number of offspring that survive the first year of life. -An estimate of the number of daughters a female produces in her lifetime. -The probability that an individual survives from. one age class to the next.

-An estimate of the number of daughters a female produces in her lifetime.

Why is the selected model of population growth appropriate for white-tailed deer? -It models species that reproduce at discrete intervals. -It models species that reproduce at very slow rates. -It models species that reproduce continuously. -It models species that have strict limits to their population sizes.

-It models species that reproduce at discrete intervals.

Select the statements that explain why very small and very large populations experience slow population growth under the logistic growth model. -The carrying capacity is larger for populations that contain very few individuals. -The intrinisic growth rate is higher when populations contain many individuals. -Small populations have fewer individuals capable of producing offspring. -Limited resources are shared among many individuals in very large populations.

-Small populations have fewer individuals capable of producing offspring. -Limited resources are shared among many individuals in very large populations.

Select the definition of generation time: -A measure of how the size of a population changes over time. -The average time between the birth of an individual and the birth of its offspring. -The average lifespan of an individual. -The interval of time between life table estimates of population size.

-The average time between the birth of an individual and the birth of its offspring.

Identify examples of evidence that a population has a size that is density dependent. -The number of progeny per adult decreases as population density increases. -A change in a population's size exhibits exponential or geometric growth. -The maximum population limit increases as population density decreases. -A population is devastated by extremely cold temperatures every few years. -A population's resources and potential mates are insufficient for all individuals.

-The number of progeny per adult decreases as population density increases. -A population's resources and potential mates are insufficient for all individuals.

In the logistic growth model, when is the population growing the fastest? -In the logistic model, the population growth rate remains constant. -The population is growing fastest at carrying capacity (K). -The population is growing fastest at the inflection point in the S curve of the logistic growth model. -The population is growing fastest when there are only a few individuals in the population.

-The population is growing fastest at the inflection point in the S curve of the logistic growth model.

What defines the limit of a population experiencing true exponential growth? -There is no limit. -Limited habitat species. -Carrying capacity. -Limited food supply.

-There is no limit.

What is the function of mark-recapture surveys? -To estimate population size. -To count the number of recaptured individuals. -To measure the immigration and emigration from an area. -To quantify the difficulty of catching individuals of a particular species.

-To estimate population size.

What is the relationship between generation time and the rate of population growth? -With a short generation time, the rate at which a population can grow is high. -There is a positive correlation between generation time and the rate of population growth. -With a short generation time, the rate at which a population can grow is low. -There is no relationship between generation time and the rate of population growth.

-With a short generation time, the rate at which a population can grow is high.

Suppose that from an initial size of 100 females, a life table based on female fecundity projects a population size of 112 females after one year. If the sex ratio of the hypothetical population is 1:1, how large will the total population be after one year? State your answer as a whole number. Total population size after one year: ________ individuals.

224

Classify each statement as describing a cohort life table or a static life table: Cannot distinguish environmental effects from differences among ages.

Cohort life table

Classify each statement as describing a cohort life table or a static life table: Is a useful strategy for sessile or short-lived organisms.

Cohort life table

Classify each statement as describing a cohort life table or a static life table: Tracks one group of individuals throughout their life spans.

Cohort life table

Classify each statement according to whether it applies to the exponential or geometric growth model: assumes continuous growth over a period of time

Exponential growth model

Classify each statement according to whether it applies to the exponential or geometric growth model: includes e, the base of natural log

Exponential growth model

Select the population growth model for a small group of white-tailed deer, which give birth each spring. -exponential growth -linear growth -logistic growth -geometric growth

Geometric growth

Classify each statement according to whether it applies to the exponential or geometric growth model: assumes growth at specific intervals over a period of time

Geometric growth model

Classify each statement according to whether it applies to the exponential or geometric growth model: includes λ, the ratio of population sizes from year to year

Geometric growth model

In a life table, the survival rate (sx) describes the ____________________________, whereas survivorship (lx) describes the ____________________________.

In a life table, the survival rate (sx) describes the PROPORTION OF INDIVIDUALS THAT SURVIVE FROM ONE AGE CLASS TO THE NEXT, whereas survivorship (lx) describes the CUMULATIVE PROPORTION OF INDIVIDUALS THAT SURVIVE TO A CERTAIN AGE CLASS.

Classify each statement as describing a stable population of bears or a population of bears with a stable age distribution: From one year to the next, a growing population consistently has about three times as many cubs as adults.

Stable age distribution

Classify each statement as describing a stable population of bears or a population of bears with a stable age distribution: The proportion of cubs to adults remains constant in a bear population that declines in size each year.

Stable age distribution

Classify each statement as describing a stable population of bears or a population of bears with a stable age distribution: A population size holds constant from one year to the next as the proportion of cubs to adults changes.

Stable population

Classify each statement as describing a stable population of bears or a population of bears with a stable age distribution: Over multiple years, the total number of bears in the population does not change as the proportion of cubs to adults decreases.

Stable population

Classify each statement as describing a cohort life table or a static life table: Collects data from individuals of all ages at a single time interval.

Static life table

Classify each statement as describing a cohort life table or a static life table: Is appropriate for mobile or long-lived organisms.

Static life table

Classify each statement as describing a cohort life table or a static life table: Measures differences between ages under the same conditions.

Static life table

When the intrinsic growth rate (r) of a population equals zero, the population size after one year (N1) is _______ the initial population size (N0). Therefore, the annual growth rate (λ) of the population equals _______.

When the intrinsic growth rate (r) of a population equals zero, the population size after one year (N1) is EQUAL TO the initial population size (N0). Therefore, the annual growth rate (λ) of the population equals 1.