Chapter 53 - Population Ecology

Population growth

________ is regulated by density- dependent variables (pp.

Intraspecific competition

________ for limited food or space, increased predation, illness, intrinsic physiological variables, and toxic chemical accumulation are examples of density- dependent limiting factors.

Ecologists

________ often begin an investigation of a population by setting limits that are appropriate to the creature being studied and the questions being addressed.

Natural selection

________ produces life history characteristics.

logarithmic scale

The ________ on the y- axis allows the number of survivors to be visible across the entire range (2- 1, 000 individuals) on the graph.

Life tables

________ and survival curves highlight particular demographic patterns.

1650

The global human population has increased rapidly since around ________, but in the last 50 years, the pace of expansion has been cut in half.

Infant mortality rates

________ and life expectancy at birth vary greatly among nations.

ecological footprint

The ________ is the total amount of land and water required to generate all of the resources that a person or group of people use and absorb all of their waste.

Population density

________, dispersion, and demography are influenced by biotic and abiotic variables.

Life history characteristics

________ are evolutionary consequences that are reflected in organism development, physiology, and behavior.

Individual dispersion

________ is influenced by environmental and social variables.

Iteroparous creatures

________ have progeny on a regular basis.

reproductive output

For sexual creatures such as birds and mammals, ________ is generally assessed as the average number of female offspring produced by females in a specific age group.

immigration

If ________ and emigration are excluded, the per capita growth rate of a population equals the birth rate minus the mortality rate.

K selection

________ and r- selection are two hypothetical life history patterns.

independent birth

A density- ________ or death rate is one that does not fluctuate with density.

logistic model

Although the ________ only fits a few real populations exactly, it is useful for projecting potential growth.

population expansion

When resources are plentiful, the exponential growth equation dN /dt= rN describes ________, where r is the intrinsic rate of rising and N is the population size.

Population growth

________ is slowed by density- dependent variations in birth and death rates, which can finally stabilize a population around its carrying capacity.

Life history characteristics

________ like brood size, maturity age, and parental caring are examples of trade- offs between competing needs for time, energy, and nutrition.