21 terms

Ch 19: Population Ecology

STUDY
PLAY
population
a group of individuals of a single species that occupy the same general area
population density
number of individuals of a species per unit of area or volume
age structure
the distribution of individuals in different age groups
life tables
track survivorship and help determine the most vulnerable stages of the life cycle
survivorship curves
plot the number of individuals still alive at each stage in the maximum life span and are classified based upon the rate of mortality over the life span of an organism
life history
set of traits that affect the organism's schedule of reproduction and survival
opportunistic life history
grow quickly, produce many offspring, type III surviorship
equilibrial life history
develop and reach sexual maturity slowly, produce few, well-cared for offspring, type I survivorship curve
exponential growth
ideal and unlimited environment
limiting factors
environmental factors that hold a population in check
carrying capacity
the maximum population size that a particular environment can sustain
logistic growth
growth rate decreases as the population size approaches carrying capacity
intraspecific competition
competition between members of the same species for limited resources
density-dependent factor
population limiting factor whose effects intensify as the population increases in density, parasitism, disease, starvation, etc
density independent factors
population limiting factors unrelated to population density, fires, floods, and storms
endangered species
one that is in danger of extinction throughout all or a significant portion of its range
threatened species
one that is likely to become endangered in the foreseeable future
invasive species
non-native species that has spread far beyond the original point of introduction
biological control
intentional release of natural enemy to attack a pest population and used to manage invasive species
population momentum
continuation of population growth as girls in the prereproductive age group reach their reproductive years
ecological footprint
estimate of the amount of land required to provide the raw materials an individual or nation consumes