Chapter 51: Population Ecology

Fitness trade

________- offs are the inescapable compromise between two traits that can not be optimized simultaneously.

UN projections

The ________ are based on three scenarios, which hinge on different values for fertility rates－the average number of surviving children that each woman has during her lifetime.

replacement rate

The ________ is the average fertility required for each woman to produce exactly enough offspring to replace herself and her offsprings father.

K

Carrying capacity, ________, is defined as the maximum number of individuals in a population that can be supported in a particular habitat over α sustained period of time.

Biotic factors

________, such as past and current interactions with other species provide habitat, food, or competition.

area of Z vivipαrαvaries

The population density- the number of individuals per unit ________ throughout its range.

geographic distribution

Most species identification guides show the range, or ________, of different species.

Analyzing birth rates, death rates, immigration rates, and emigration rates are fundamental to demography

the study of factors that determine the size and structure of populations through time

51.5 Case Study

Human Population Growth

Range

geographic distribution

population density

the number of individuals per unit area

immigration

occurs when individuals enter a population by moving from another population

emigration

occurs when individuals leave a population to join another population

demography

the study of factors that determine the size and structure of populations through time

age structure

how many individuals of each age are alive

generation time

the average time between a mother’s first offspring and her daughter’s first offspring

age class

a group of individuals of a specific age

cohort

a group of the same age that can be followed through time

Survivorship

proportion of offspring produced that survive, on average, to a particular age (the opposite of mortality)

Fitness trade-offs

the inescapable compromise between two traits that cannot be optimized simultaneously