Key Idea: Topic 1.2 is about how populations change and how that movement reshapes places. It pulls together four ideas: 1.2.1 — population structure: reading a population pyramid for a country's age and sex make-up, plus natural increase and the sex ratio. 1.2.2 — megacities: what a megacity is (10 million+) and the drawbacks and benefits of cities growing very fast, felt by individuals and wider society. 1.2.3 — forced migration: people driven from home with no real choice — by political, environmental, social or developmental causes — becoming refugees or internally displaced. 1.2.4 — voluntary internal migration: people choosing to move within their country, changing both the source they leave and the destination they reach. This is core content, examined on Paper 2 — a data-response read off a population pyramid, line graph or map, a short structured Explain, and it can feed the extended-response essay.
👥 1.2.1 — Population structure: pyramids, age & sex
A population pyramid shows a country's age and sex structure — males on the left, females on the right, youngest at the bottom, with bar length = the share in each group. The shape tells the story, and the skill examiners test is reading the bars (a figure) then describing the shape, with no reasons for a Describe command.
[Diagram: geo-population-pyramid]
🏙️ 1.2.2 — Megacities & the consequences of rapid growth
A megacity has 10 million or more inhabitants. Most are in lower- and middle-income countries, mainly in Asia and Africa, where cities grow fastest. Rapid growth has two sides — drawbacks and benefits — and a strong answer names who feels each: an individual (one resident) or wider society (the whole city or country).
🚨 1.2.3 — Forced migration & displacement
Forced migration is movement people have no real choice about — they are pushed out by danger or disaster, not pulled by opportunity. Forced migrants who cross an international border become refugees; those forced to flee but who stay inside their own country are internally displaced persons (IDPs). An Explain answer must name the cause and the mechanism that forces the move.
🧳 1.2.4 — Voluntary internal migration & place change
Voluntary internal migration is choosing to move home within your own country — usually from low-opportunity source areas to high-opportunity destinations (often big cities). It changes both places, and the effects are usually opposite: the source is left ageing and hollowed-out, while the destination gains workers but faces pressure on housing and services. Because young workers concentrate in a few places, it can even hold back national development.
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Exam Tips
- For a pyramid, line graph or map: DESCRIBE first (shape, highest/lowest, a figure WITH UNITS, any clustering), and only Explain if the command asks — Describe needs no reasons.
- Learn the figures exactly: megacity = 10 million+; replacement is not needed here, but natural increase = births − deaths (no migration).
- Keep the scales straight — individual vs wider society for megacities; source vs destination for migration. Examiners reward answers that name the scale.
- Refugee = crossed a border; IDP = stayed inside the country. Forced = no choice (pushed); voluntary = a chosen move (pulled).
- Always name real cases: Syria, Lake Chad and Three Gorges Dam for forced migration; Queensland/NSW for internal migration; Delhi or Lagos for megacities.
- On the [10] Examine/Evaluate, weigh both sides with named places and figures, then finish with an explicit, justified judgement.