APHUG unit 2

Agricultural Revolution

The shift from hunting and gathering to deliberate plant cultivation and animal domestication, which allowed permanent settlements and population growth

Agricultural density

The number of farmers per unit of arable land

Anti natalist policies

Government policies that discourage or limit births to slow population growth

Arable land

Land suitable for growing crops

Arithmetic density

The total number of people per unit of land area (also called population density)

Age structure

The distribution of a population among age groups, often shown as the percentage of people in young, working age, and elderly categories

Baby boom

A period of sharply increased birth rates, especially in the US and other MDCs from about 1946 to 1964, after World War II

Census

An official, periodic count of a country’s population that also gathers demographic data

Carrying capacity

The maximum population size an environment can sustain over time given available resources

Crude Birth Rate (CBR)

The number of live births per 1,000 people in a population per year

Crude Death Rate (CDR)

The number of deaths per 1,000 people in a population per year

Demographic Transition

A model describing how a country’s population changes from high birth and death rates to low birth and death rates as it develops economically (Stages 1

Demography

The scientific study of population characteristics, including size, distribution, and change

Dependency Ratio

The number of people too young or too old to work (under 15 and over 64) compared to the number of people in the working age population (ages 15 to 64)

Doubling Time

The number of years it takes for a population to double in size, given its current growth rate

Ecumene

The portion of Earth’s surface that is permanently inhabited by humans

Epidemiologic Transition

A model describing the distinctive causes of death in each stage of the Demographic Transition, shifting from infectious diseases to chronic and degenerative diseases as a society develops

Epidemiology

The branch of medical science that studies the causes, distribution, and control of diseases in populations

Industrial Revolution

The period beginning in the late 1700s in which technological advances in production, transportation, and sanitation led to rapid population growth, urbanization, and declining death rates

Infant Mortality Rate (IMR)

The number of deaths of infants under age 1 per 1,000 live births per year

Life Expectancy

The average number of years a person can expect to live, based on current mortality rates

Maternal mortality rate

The number of women who die from pregnancy

Medical Revolution

The 20th century development and diffusion of medical technologies (such as vaccines and antibiotics) from MDCs to LDCs that sharply reduced death rates and lengthened life expectancy

Natural Increase Rate (NIR)

The percentage by which a population grows in a year, calculated as CBR minus CDR (divided by 10 to give a percentage), not including migration

Neo Malthusians

Modern thinkers who support Malthus’s concerns that population growth will outpace resources and who stress the environmental effects of overpopulation

One Child Policy (China)

An anti natalist policy enacted in 1979 that limited most Chinese couples to one child, which slowed population growth but led to an imbalanced sex ratio and an aging population (ended in 2015 and replaced with a two child policy, then a three

Overpopulation

A situation in which the number of people in an area exceeds the capacity of the environment to support them at a reasonable standard of living

Pandemic

A disease outbreak that spreads across a very large region, often across multiple continents or worldwide

Physiological density

The number of people per unit of arable land

Population Pyramid

A bar graph that shows the age and sex composition of a population, with males typically on the left and females on the right

Population density

The number of people living in a given unit of area, usually per square mile or kilometer (see arithmetic density)

Elderly support ratio

The number of working age people (ages 15 to 64) for every person aged 65 or older

Pronatalist policies

Government policies that encourage higher birth rates, such as offering financial incentives, tax benefits, or paid parental leave

Sex Ratio

The number of males per 100 females in a population

Total Fertility Rate (TFR)

The average number of children a woman in a population is expected to have during her childbearing years (about ages 15 to 49); a TFR of about 2.1 is replacement level

Thomas Malthus

English economist who argued in 1798 that population grows geometrically while food supply grows arithmetically, leading to eventual shortages, famine, and disease

Youth Dependency Ratio

The number of people under age 15 compared to the number of people in the working age population (ages 15 to 64)

Zero Population Growth (ZPG)

A condition in which a population’s growth rate is zero, meaning the birth rate equals the death rate (NIR of 0), so the population stays stable