unit 2 vocab

Population distribution

the arrangement or spread of people living in a given area

Population density

number of individuals per unit area

Midlatitudes

the regions between 30°N–60°N and 30°S–60°S

Social stratification

the division of society into groups arranged in a social hierarchy

Arithmetic population density

the total number of people divided by the total land area

Physiological population density

the number of people per unit area of arable land

Arable

suitable for growing crops

Carrying capacity

the largest number of individuals an environment can support

Agricultural population density

number of farmers per unit of arable land

Redistricting

the drawing of new electoral district boundary lines in response to population changes

Overpopulation

too many people in an area relative to available resources and technology

Age-sex composition graph

another name for a population pyramid

Population pyramid

a bar graph representing the distribution of population by age and sex

Cohort

a group of individuals of the same age

Birth deficit

a slowdown of births caused by war or separation of the sexes during conflict

Baby boom

a temporary increase in the birth rate especially following World War II

Baby bust

a period marked by a greatly decreased birth rate following a baby boom

Echo

the generation of children born to baby boomers creating another bulge in the population pyramid 25–40 years later

Dependency ratio

the ratio of people under age 15 and over 64 to those ages 15–64

Potential workforce

society’s expected labor force ages 15–64

Dependent population

those who rely on the working population for support such as the young and elderly

Crude birth rate (CBR)

the total number of live births per year for every 1

Total fertility rate (TFR)

the average number of children born to a woman during her childbearing years

Anti-natalist policies

government policies to reduce birth rates such as China’s one-child policy

Pro-natalist policies

policies that encourage births such as paid parental leave and tax incentives

Life expectancy

the average number of years a person is expected to live

Infant mortality rate

the number of deaths of infants under age one per 1

Demographic transition model (DTM)

a model showing how population size changes as a country develops economically

Expansive population pyramid

population with high birth rates and low life expectancy common in less developed countries

Epidemiological transition model (ETM)

identifies distinctive causes of death in each stage of the demographic transition

Stationary population pyramid

a population with roughly equal birth and death rates

Crude death rate (CDR)

the total number of deaths per year for every 1

Rate of natural increase (RNI)

the percentage by which a population grows each year calculated as CBR minus CDR

Immigrants

people who move to and settle in a country in which they were not born

Emigrants

people who leave their country or region to live elsewhere

Demographic balancing equation

a formula that calculates population change as births minus deaths plus immigration minus emigration

Malthusian Theory

the idea that population growth will outpace food supply

Neo-Malthusians

modern supporters of Malthus’s theory arguing population growth depletes nonrenewable resources

Migration

the movement of people from one place to another

Voluntary migration

movement based on personal choice often for opportunity

Push factors

conditions that cause people to leave their homeland

Pull factors

conditions that attract people to a new location

Asylum

protection granted by a country to refugees fleeing danger or persecution

Intervening obstacles

barriers or challenges that hinder migration

Ravenstein’s Laws of Migration

theories that describe migration patterns such as short distances and step migration

Distance decay

the diminishing interaction between two places as distance increases

Gravity model of migration

predicts movement based on population size and distance larger places attract more migrants

Step migration

migration to a distant destination that occurs in stages

Counter migration

the return of migrants to their original region

Return migration

the voluntary movement of immigrants back to their place of origin

Forced migration

migration in which people have no choice but to move

Internally displaced person (IDP)

a refugee who remains within their own country

Refugees

people who flee their country to escape persecution conflict or disaster

Chain migration

migration that follows others from the same origin who previously moved

Ethnic enclaves

neighborhoods or areas where people of similar ethnicity settle together

Xenophobia

intense or irrational dislike or fear of people from other countries

Brain drain

the loss of highly educated or skilled workers who emigrate to other countries

Remittances

money sent by migrants back to family members in their home country