Birth, death & natural-increase rates
Three linked rates drive population change. Birth rate (BR) = live births per 1,000 people per year; death rate (DR) = deaths per 1,000 per year -- both need the "per 1,000" AND "per year" qualifiers to score. Natural increase (NI) rate = BR - DR, per 1,000 per year; divide by 10 to get a percentage. BR > DR gives natural increase; DR > BR gives natural decrease. NI is NOT total population growth, which also needs net migration (topic 1.2).
Demographic Transition Model: 5 stages
The DTM tracks how birth and death rates change as a country develops, over 5 stages. Stage 1: both high, natural increase low. Stage 2: death rate falls sharply while birth rate stays high, so growth is rapid. Stage 3: birth rate falls too, while death rate falls slowly, so growth slows. Stage 4: both low, increase low. Stage 5: birth rate falls below death rate, giving natural decrease and ageing. Each stage is set by the RELATIONSHIP between the rates, not a number.
Over-, under- & optimum population
These terms compare population to the RESOURCES and technology available, not to headcount or density. Optimum population = the size giving the highest standard of living with current resources. Over-population = too many people for those resources, so living standards would rise if population fell. Under-population = too few to use them fully, so standards would rise if population grew. New technology can raise the optimum, easing over-population without anyone moving.
Drawn from real examiner reports.
Falling rates ≠ population decline
Seeing that both birth and death rates have fallen and concluding the population is declining is faulty. A population declines naturally only when death rate is now HIGHER than birth rate. If birth rate has fallen but still exceeds death rate, it is still growing, just more slowly. Compare the two CURRENT rates -- which is larger now -- not the direction each has moved.
w23 P12 Q1(a)(ii)
Botched rate calculations
Rate questions are lost to avoidable slips. Three recurring errors: (1) wrong formula -- dividing population by births, not births by population; (2) multiplying by 1,000 when the data is ALREADY a per-1,000 rate; (3) transposing the birth- and death-rate values. Check whether each figure is a raw count or a rate, and subtract DR FROM BR.
w23 P12 Q1(a)(iii); s23 P13 Q1(a)(i)
Definitions drop 'per 1,000'/'per year'
The topic's key definition trap. "Birth rate is how many babies are born" earns nothing. Full: birth rate = live births per 1,000 of the population in a year; death rate = deaths per 1,000 in a year. "Per 1,000" makes figures comparable between differently sized countries; "per year" makes it a rate, not a one-off count. Drop either and it is incomplete.
w22 P11 Q1(a)(i)
Vague 'overpopulation' as a cause
Asked WHY a population grows rapidly, weak answers give unqualified "overpopulation" or "lack of resources" rather than a mechanism from the resource given -- labels, not explanations. Name the real driver (e.g. a high birth rate because children provide farm labour) and link it to the data or place in the question.
w23 P21 Q2(b)
Dense ≠ over-populated
Density and over-population are not the same. Density = people per km2 (a measured number). Over-population = a JUDGEMENT that there are too many people for the resources and technology available. A densely populated rich city can sit below its optimum; a sparsely populated but resource-poor area can be over-populated. Never infer over-population from density alone.
Pro-natalist vs anti-natalist mix-up
These opposite policies are easily swapped. Pro-natalist aims to RAISE the birth rate (e.g. Singapore's "Have Three or More" campaign, 1987). Anti-natalist aims to LOWER it (e.g. China's former one-child policy, 1979). Match the policy to the problem: too few births needs pro-natalist, too-rapid growth needs anti-natalist. Reverse the direction and the answer is wrong.
Natural increase vs total population growth
A testable wrong belief: that natural increase equals a country's population growth rate. Natural increase is only births minus deaths -- it ignores migration. Total growth = natural increase plus or minus net migration (topic 1.2). A country with positive natural increase can still shrink if many emigrate. Ask whether a question means NATURAL or TOTAL change.
Nail the 7-mark policy case study
Name a REAL country and policy on the population-policy question (e.g. China's one-child policy); vague "some countries control population" stays Level 1. Give the reason it was introduced, then one intended effect (slower growth) and one unintended one (ageing).
Develop ideas, don't list
On growth and case-study questions, an undeveloped bullet list is a Level 1 answer. Develop 2-3 ideas -- each with a linked consequence and place-specific detail or a statistic -- not many bare points. Depth beats breadth: three developed points beat eight listed ones.
Quote exact figures with units
Describing population data, quote EXACT figures with units (per 1,000, %) rather than vague "about", "nearly" or "majority" (wrong for under 50%). Pair each value with a trend word -- rose, fell, narrowed. Data-backed wording separates a developed answer from a basic one.
Read DTM stages by the gap
Identify a DTM stage from the RELATIONSHIP between the two lines, not a fixed number: a wide gap with high birth rate = Stage 2; birth rate falling toward a low death rate = Stage 3; the lines crossing = Stage 5. The gap IS natural increase -- read what it does, not one rate.
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