Population and Demography Lecture Notes

Vocabulary flashcards covering demographic concepts, density measures, population pyramids, Malthusian vs. Boserupian theories, the DTM and ETM frameworks, and global population policies.

Carrying capacity

The largest population an area's resources can support without damaging the environment or using resources unsustainably.

Ecumene

The part of Earth's land surface that is permanently inhabited by people.

Population density

A measure of population per unit of area (people per sq mi or sq km).

3 major population centers

East Asia, South Asia, and Europe; together they hold more than half of the world's population.

The "5 Too's" (physical factors)

Physical conditions that people avoid settling in: places that are too hot, too cold, too wet, too dry, or too hilly.

The "5 Needs" (human factors)

Human factors that attract settlement: places where there are jobs, political stability, infrastructure, trade, and community services.

Arithmetic density

$\text{Total population} \div \text{total land area}$; the simplest measure of density, but treats desert and farmland the same.

Physiological density

$\text{Total population} \div \text{arable (farmable) land}$; best shows pressure on the land that grows food.

Agricultural density

$\text{Number of farmers} \div \text{arable land}$; provides a clue about farming technology and development.

Arable land

Land that can be farmed to grow crops.

High agricultural density

Many farmers per unit of farmland; characterized by farming by hand and low output per farmer; typical of LDCs.

Low agricultural density

Few farmers per unit of farmland; characterized by mechanized farms and high output per farmer; typical of MDCs.

Egypt case study (density)

Has an arithmetic density of about $257/\text{sq mi}$ but a physiological density of about $3,500/\text{sq mi}$, where $95\%$ of people live on $3\%$ of the land along the Nile.

Scale and density

A country can look evenly settled at a world scale but show crowded and empty areas at a country or city scale; scale changes the story a map tells.

Life expectancy

The average number of years a person is expected to live, based on current conditions where they are born.

Crude Birth Rate (CBR)

The number of live births per $1,000$ people per year.

Crude Death Rate (CDR)

The number of deaths per $1,000$ people per year.

CBR benchmarks

High CBR is above $30$; Low CBR is below $18$ (the U.S. is about $10.7$).

CDR benchmarks

High CDR is above $12$; Low CDR is below $7$ (the U.S. is about $9.2$).

Natural Increase Rate (NIR)

$(\text{CBR} - \text{CDR}) \div 10$, shown as a percent; represents population growth from births and deaths only.

What NIR does NOT include

Migration (immigration and emigration).

Natural decrease

When the CBR is lower than the CDR, causing the population to shrink without migration.

Total Fertility Rate (TFR)

The average number of children a woman has in her lifetime.

Replacement rate

The TFR needed for a population to replace itself without migration; approximately $2.1$ where child mortality is low.

Why replacement rate is 2.1, not 2.0

Two children replace the two parents; the extra $0.1$ covers children who die before adulthood and the slightly higher number of boys born.

Replacement rate in LDCs

Often $2.5\text{--}3.3$ or higher, because high child mortality means more births are needed for enough children to survive.

Infant Mortality Rate (IMR)

Deaths of babies under age $1$ per $1,000$ live births in a year.

Drivers of TFR

Behavioral factors: female education, access to family planning, mother's age at first birth, government policy, and culture.

Drivers of replacement rate

Mortality factors: how many infants and children die before adulthood.

TFR vs. NIR for predicting the future

TFR is the better predictor because NIR only shows growth now, while TFR reveals whether each generation replaces the one before it.

Population pyramid

A chart showing the percent of a population in each age group, split by sex, with males on the left and females on the right.

Cohort

One age and sex group shown as a single bar on a population pyramid.

Expansive pyramid

A pyramid with a broad base that narrows quickly; indicates high birth and death rates and fast growth; typical of LDCs such as Sub-Saharan Africa and Haiti.

Stationary pyramid

A pyramid with fairly even bars from bottom to top; indicates a TFR near $2.1$ and slow or no growth; typical of MDCs such as the U.S., U.K., and France.

Constrictive pyramid

A pyramid with a base narrower than the middle or top; indicates a TFR below $2.1$ and an aging, shrinking population; seen in Germany, Italy, and Japan.

Dependency ratio

$((\text{Ages } 0\text{--}14 + \text{ages } 65+) \div \text{ages } 15\text{--}64) \times 100$; the number of dependents per $100$ working-age people.

Young dependency

A situation where most dependents are children (seen in expansive pyramids); creates a need for schools, childcare, and future jobs.

Old dependency

A situation where most dependents are elderly (seen in constrictive pyramids); creates a need for pensions, health care, and workers.

Sex ratio

$\text{Number of males} \div \text{number of females}$; a value above $1.00$ indicates more males, while below $1.00$ indicates more females.

Bulge on a pyramid

An age group larger than surrounding bars; often caused by in-migration (students, soldiers, workers, retirees) or a past baby boom.

Pinch on a pyramid

An age group smaller than surrounding bars; often caused by out-migration, war deaths, or years of low births.

Reasons pyramid sides are uneven

Women living longer than men, job opportunities that draw mostly men, war deaths among men, and cultural son preference.

Male working-age bulge at country scale

A demographic indicator that signals large inflows of migrant workers, as seen in the UAE and Qatar.

Lakeview County pyramid profile

Features a narrow base, a pinch at ages $20\text{--}34$, and a bulge at ages $60\text{--}74$; indicates a retirement destination that young adults leave.

Clemson pyramid profile

Features a huge bulge at ages $20\text{--}24$ resulting from incoming college students.

Hilton Head pyramid profile

Features a wide top at ages $50\text{--}79$ and a thin base due to retirees moving in.

Thomas Malthus

Theorist who argued that population grows exponentially while food production grows arithmetically, eventually leading to a crisis point.

Exponential growth (Malthus)

Pattern by which population increases geometrically: $1, 2, 4, 8\dots$

Arithmetic growth (Malthus)

Pattern by which food supply increases linearly: $1, 2, 3, 4\dots$

Crisis point

The intersection point on the Malthus graph where population surpasses food supply, initiating scarcity and population decline.

Positive checks

Events such as famine, war, and disease that raise the death rate and reduce population size.

Preventive checks

Actions such as delayed marriage and having fewer children that lower the birth rate and slow population growth.

Paul Ehrlich

Neo-Malthusian author of The Population Bomb (1968) who linked overpopulation to environmental damage and called for limiting growth.

Neo-Malthusian

A modern thinker who updates Malthus's pessimistic perspective, often focusing on environmental harm and resource depletion.

Ester Boserup

Optimistic theorist who argued that population pressure stimulates agricultural innovation, increasing food output and carrying capacity.

Malthus graph vs. Boserup graph

In Malthus's model, the rising population curve crosses the flatter food line; in Boserup's model, both food and population lines rise together and never cross.

Evidence supporting Boserup

The emergence of new farming technologies (such as the Green Revolution) that raised food production faster than population grew.

Demographic Transition Model (DTM)

A model showing how crude birth rates, crude death rates, and natural growth change across $5$ stages as a country develops economically.

Epidemiological Transition Model (ETM)

A model showing how the primary causes of death shift as a country undergoes economic development.

DTM Stage 1: High Stationary

Stage with high CBR and high CDR, resulting in low, fluctuating growth; no countries remain here today; corresponds to ETM Age of Pestilence and Famine.

DTM Stage 2: Early Expanding

Stage with high CBR and rapidly falling CDR, leading to very rapid population growth; typical of most LDCs; corresponds to ETM Age of Receding Pandemics.

DTM Stage 3: Late Expanding

Stage with falling CBR and continuing CDR declines, yielding moderate growth as urbanization begins (e.g., Brazil); corresponds to ETM Age of Degenerative Diseases.

DTM Stage 4: Low Stationary

Stage with low CBR and low CDR, a TFR near $2.1$, and NIR near zero (e.g., USA, Japan, France, UK); corresponds to ETM Age of Delayed Degenerative Diseases.

DTM Stage 5: Declining

Stage where CBR drops below CDR, leading to an aging and declining population (e.g., Germany); corresponds to ETM Age of Re-emerging and Lifestyle Diseases.

Age of Pestilence and Famine

ETM Stage 1; characterized by high mortality resulting from infectious diseases, poor sanitation, and food scarcity.

Age of Degenerative Diseases

ETM Stage 3; characterized by mortality dominated by chronic conditions such as heart disease, cancer, stroke, and dementia.

Age of Re-emerging and Lifestyle Diseases

ETM Stage 5; characterized by chronic and lifestyle illnesses (obesity, stress) alongside re-emerging infections and drug-resistant bacteria.

Stage 1 to Stage 2 trigger

The sharp drop in death rate driven by improvements in food supply, sanitation, and medical care.

Stage 2 to Stage 3 trigger

The drop in birth rate driven by increasing urbanization, access to family planning, and expanding educational opportunities for women.

Why CDR drops before CBR

Medical and sanitation advances spread rapidly through societies, whereas cultural customs and family size traditions change much more slowly.

Age structure and CDR

Older populations have higher death rates even with superior health care, causing some MDCs to have higher CDRs than demographically younger LDCs.

Population policy

Government laws and strategies specifically designed to influence the size, growth rate, or geographical distribution of a population.

Anti-natalist policy

A government policy aimed at lowering fertility and slowing population growth; most commonly implemented in DTM Stages $2\text{--}3$.

Pro-natalist policy

A government policy aimed at raising fertility rates and stabilizing or increasing population; most commonly implemented in DTM Stages $4\text{--}5$.

Anti-natalist tools

Methods ranging from voluntary to coercive: education, public health campaigns, financial incentives, and legal restrictions enforced by fines.

Pro-natalist tools

Interventions including cash payouts, tax breaks, paid parental leave, subsidized childcare, public awareness campaigns, and housing support.

China's One-Child Policy (1979–2016)

A coercive anti-natalist policy that reduced TFR from $2.7$ to about $1.0$ by $2025$, leading to rapid population aging, skewed sex ratios favoring males, and labor shortages.

China's pro-natalist policy transition

Shifted to a Two-Child policy ($2015$), a Three-Child policy ($2021$), and later tax breaks, housing assistance, and childcare subsidies ($2025$).

India's family planning program

The world's first national family planning program ($1952$); shifted from coercive measures in the 1970s to voluntary health care, education, and female empowerment, dropping TFR from $6.0$ to about $2.0$.

France pro-natalism (1920)

Enacted following approximately $1.4\text{ million}$ WWI deaths; banned birth control promotion and awarded national medals to mothers of large families.

USSR "Mother Heroine" award (1944)

A pro-natalist state award created for mothers who raised $10+$ children following roughly $27\text{ million}$ Soviet deaths in WWII.

Russia's modern pro-natalism

Initiatives including "maternity capital" cash grants ($2007$), reviving the Mother Heroine award ($2022$), and banning "child-free propaganda" ($2024$); TFR remains at about $1.4$.

Singapore pro-natalism

One of the world's most generous financial pro-natalist programs; despite incentives, TFR fell to $0.87$ in $2025$, prompting greater reliance on immigration.

Causes of low fertility in DTM Stages 4–5

Expansion of female higher education, career pursuits, delayed marriage, and the high financial cost of raising children.

Why financial incentives often fail to raise births

Direct cash subsidies do not resolve fundamental structural causes such as career-family balance, housing and childcare costs, and evolving social norms.