vocab 3

k-strategist species

species whose populations fluctuate at or near the carrying capacity (K) of the environment in which they reside

k-selection

the selection of combinations of traits in an organism that trade off between quantity and quality of offspring

climax species

when this ecosystem stops experiencing sporadic change and instead reaches stability

late successional species

plant species that can germinate and grow with limited resources

r-selected species

those that produce a large number of offspring and contribute few resources to each individual offspring

biotic potential

maximum rate at which the population of a given species can increase when there are no limitations on it rate of growth

survivorship curves

graph showing the number of survivors in different age groups for a particular species

j-shaped curve

curve with a shape similar to that of the letter J; can represent prolonged exponential growth

s-shaped curve

leveling off of an exponential, J-shaped curve when a rapidly growing population reaches or exceeds the carrying capacity of its environment and ceases to grow

age structure diagrams

a diagram showing the percentage of the population (or number of people of each sex) at each age level in a population

total fertility are (TFR)

estimate of the average number of children who will be born alive to a woman during her lifetime if she passes through all her childbearing years (15-44) conforming to age-specific fertility rates of a given year. More simply, it is an estimate of the average number of children that women in a given population will have during their childbearing years

replacement rate

average number of children a couple must bear to replace themselves. The average for a country or the world usually is slightly higher than two children per couple, mostly because some children die before reaching their reproductive years

life expectancy

average number of years a newborn infant can be expected to live

emigration

movement of people out of a specific geographic area

per capita

for each person; in relation to people taken individually

immigration

migration of people into a country or area to take up permanent residence

carrying capacity

maximum population of a particular species that a given habitat can support over a given period

density-dependant factors

factors where the size/density of the population will influence an individual's probability of survival

density-independant factors

factors that limit a population growth, regardless of population density (size)

rule of 70

doubling time (in years) = 70/(percentage growth rate)

population growth rate

the percentage growth of a population in a year, computed as the crude birth rate minus the crude death rate

gross domestic product (GDP)

annual market value of all goods and services produced by all firms and organizations, foreign and domestic, operating within a country

demographic transition

hypothesis that countries, as they become industrialized, have declines in death rates followed by declines in birth rates

birth rates

annual number of live births per 1000 people in the population of a geographic area at the midpoint of a given year

death rates

annual number of deaths per 1000 people in the population of a geographic area at the midpoint of a given year

intrinsic rate

rate at which a population could grow if it had unlimited resources

infant mortality rate

number of babies out of every 1000 born each year who die before their first birthday

developed countries

country that is highly industrialized and has a high per capital GDP

developing countries

country that has low to moderate industrialization and low to moderate per capital GDP. most are located in africa, asia, and latin america

demographics

the statistics such as births, deaths, income, or the incidence of disease, which illustrate the changing structure of human populations

industrial country

countries whose gross domestic product and exports contain a large share of industrial production

transitional country

a third world country that is in a transition process based on more liberal, market-friendly structures and associated features of liberal democracy