IB ESS Topic 8.1 SL Notes

A comprehensive set of practice questions (Question and Answer format) covering the key concepts from the lecture notes on human populations, fertility, policies, migration, age–sex pyramids, and the Demographic Transition Model.

What are the demographic tools used to quantify human population size?

Crude birth rate (CBR), crude death rate (CDR), total fertility rate (TFR), doubling time (DT) and natural increase rate (NIR).

What are inputs to a human population and how are they measured?

Inputs are births and immigration; measured by crude birth rate (CBR) and immigration rate per 1,000 population per year, applicable from towns to global scales.

What are outputs from a human population and how are they measured?

Outputs are deaths and emigration; measured by crude death rate (CDR) and emigration rate per 1,000 population per year, applicable at various scales.

What does the Total Fertility Rate (TFR) measure?

The average number of births per woman of childbearing age.

How do fertility rates above or below 2.0 affect population size, and what is the replacement fertility value?

Rates above 2.0 lead to growth; rates below 2.0 lead to decline. Replacement fertility is about 2.0 births per woman.

What are typical replacement fertility values for MEDCs and LEDCs, and why do they differ?

Approximately 2.03 for MEDCs and 2.16 for LEDCs, due to infant/child mortality differences.

What is life expectancy?

The average number of years a person can be expected to live, usually from birth, assuming demographic factors remain unchanged.

How is Natural Increase Rate (NIR) calculated?

NIR = birth rate − death rate; can be expressed per 1,000 people or as a percentage (NIR% = (CBR − CDR)/10).

What is Doubling Time and how is it calculated?

The number of years it would take a population to double at the current growth rate; DT ≈ 70 ÷ NIR (percent).

What do UN projection models indicate about future human population growth?

They indicate three scenarios linked to future fertility rates, with uncertainty about how fertility, mortality, and migration will change.

Describe the UN High Fertility Scenario.

Fertility remains higher than the median with slower declines, potentially yielding a higher peak population.

Describe the UN Probabilistic Median scenario.

The most likely scenario; uses current trends in fertility, mortality, and migration to provide a central estimate for the peak population and timing.

Describe the UN Low Fertility Scenario.

Fertility declines faster than expected, leading to an earlier and lower peak population.

What is the difference between anti-natalist and pro-natalist population policies?

Anti-natalist policies aim to reduce births; pro-natalist policies aim to increase births or support families.

Give examples of direct influencing population growth policies.

Financial incentives to have more children, extended parental leave, tax breaks, sex education, and improved access to contraception.

What are some cultural or religious factors that influence fertility and contraception usage?

Cultural/religious beliefs can promote large families or discourage contraception; gender norms, son preference, and early marriage can affect fertility.

What was China's anti-natalist policy and when did it run?

The one-child policy, 1979–2015.

What change did China announce in 2015 regarding family size?

Relaxed policy to allow three children per couple (three-child policy).

What was China’s total fertility rate in 2022?

1.18 births per woman, contributing to aging population and prompting policy shifts toward encouraging more children.

What is Singapore’s experience with pro-natalist policy and its outcome?

Pro-natalist incentives to have three or more children, but fertility rate remained low due to high costs and women’s workforce participation.

What are indirect influences on population growth?

Investing in education (especially for girls), gender equality, and improved public health care, which tend to decrease growth.

How does urbanisation relate to birth rates and what method is most effective to reduce population pressure?

Urbanisation often lowers birth rates; policies targeting female education and female participation in the workforce are viewed as most effective at reducing population pressure.

What role does migration play in population policies?

Migration policies can influence growth; immigration can offset low birth rates and help labor markets, while emigration can affect aging populations.

What are some immigration benefits for host countries?

Immigrants join the workforce, are taxed, help fund pensions, and can remit income to their countries of origin.

How do Netherlands and Indonesia illustrate different migration policy directions?

Netherlands tends to encourage immigration; some Asian countries like Indonesia have tighter immigration controls.

What is an age–sex pyramid and what does it show?

A graphical representation of a population by age and sex, shown in absolute numbers or percentages.

What is the Demographic Transition Model (DTM)?

A model describing changes in birth and death rates in a population through five stages over time.

Describe Stage 1 (High stationary) of the DTM.

High birth rates and high death rates; pre-industrial conditions; population grows slowly.

Describe Stage 2 (Early expanding) of the DTM.

Death rates fall due to improvements in sanitation, nutrition, and medicine; birth rates remain high; rapid population growth.

Describe Stage 3 (Late expanding) of the DTM.

Birth rates fall due to contraception, education, and women’s emancipation; population growth slows and starts to level off.

Describe Stage 4 (Low stationary) of the DTM.

Low birth and death rates; stable population sizes in industrialised countries.

Describe Stage 5 (Declining) of the DTM.

Fertility falls below replacement; population may decline; aging workforce.

What are the limitations of the DTM?

Based on changes in industrialised countries; fifth stage was added later; death-rate declines and urbanisation may vary; some economies skip stages.

What is the relationship between DTM and age–sex pyramids?

DTM stage influences the shape of the age–sex pyramid; transitions move from broad, youthful pyramids to more rectangular or aged shapes.

How might Indonesia illustrate progression through the DTM in the 1970–2010–2050 period?

Illustrates a transition from a younger population to an aging structure as fertility declines over time, reflecting DTM progression.

How does years of schooling for women affect total fertility rate (TFR)?

Higher female education is typically associated with lower TFR due to delayed childbearing, increased access to contraception, and greater economic opportunities.