Introduction to Ecology

Dispersion

________: the pattern of spacing among individuals within the boundaries of the population.

population density

Increasing ________ intensifies competition for resources and results in a lower birth rate.

Reproductive strategy

________ has a strong effect on subsequent age classes of a population.

Predators

________ kill few prey when the prey population is low, more prey when the population is higher.

Life history traits

________ are evolutionary outcomes reflected in the development, physiology, and behavior of an organism.

Semelparity

________: produce all offspring in single reproductive event.

organisms life history

A(n) ________ comprises the traits that affect its schedule of reproduction and survival.

Uniform

________: members of a population are dispersed relatively evenly.

Populations

________ are described by their boundaries and size.

Random

________: members of a population are distributed without a predictable pattern.

Semelparous organisms

________ have batches of young the same age, called cohorts.

Population ecology

________: the study of populations in relation to their environment.

Density

________: the number of individuals per unit area or volume.

Iteroparity

________: reproduce in successive years or breeding seasons.

Iteroparous organisms

________ have young of different ages.

R selection

________: density- independent selection, selects for life history traits that maximize reproduction.

Population density

________ is determined by immigration and emigration.

Density

________- dependent factors: mortality factor that varies with population density.

Density

________- dependent birth and death rates are an example of negative feedback that regulates population growth.

Population ecology

the study of populations in relation to their environment

Population

a group of individuals of a single species living in the same general area

Density

the number of individuals per unit area or volume

Dispersion

the pattern of spacing among individuals within the boundaries of the population

Clumped

members of a population are clustered in groups

Uniform

members of a population are dispersed relatively evenly

Random

members of a population are distributed without a predictable pattern

Semelparity

produce all offspring in single reproductive event

Iteroparity

reproduce in successive years or breeding seasons

Seasonal iteroparity

distinct breeding seasons

Continuous iteroparity

reproduce repeatedly at any time of the year

Exponential population growth

population increase under idealized conditions

Carrying capacity(K)

the maximum population size the environment can support

Density-dependent factors

mortality factor that varies with population density

Density-independent factors

mortality factor whose influence is not affected by changes in population size or density

Physical factors

weather, drought, flood, fire

r-selection

density-independent selection, selects for life history traits that maximize reproduction

K-selection

density-dependent selection, selects for life history traits that are sensitive to population density