IB ESS HL 8.1 Human Populations Questions

Practise IB ESS HL 8.1 by analysing demographic projections and age structures and evaluating population policies across societies.

Exam points

Calculate natural increase, doubling time and fertility measures from demographic tables, with units.
Read or sketch age-sex pyramids to infer age structure, population momentum and future change.
Compare population projections, calculate scenario ranges and link outcomes to fertility assumptions.
Identify DTM stages from birth/death patterns and assess the model's assumptions or limitations.
Compare countries' DTM stages through historical, cultural, economic and social factors.
Evaluate how rapid population growth increases resource demand and environmental pressures.
Compare direct controls with indirect development policies using fertility, mortality or migration outcomes.

Covered syllabus points

8.1.1—Population inputs 8.1.2—Population outputs 8.1.3—Population dynamics metrics 8.1.4—Global population growth models 8.1.5—Direct population policies 8.1.6—Indirect population policies 8.1.7—Age-sex pyramids 8.1.8—Demographic transition model 8.1.9 (HL)—Rapid population growth 8.1.10 (HL)—Age-sex pyramids 8.1.11 (HL)—DTM pattern analysis 8.1.12 (HL)—Environmental migration

[Maximum number: 9]

Figure 1: Crude birth rate, crude death rate, total population (1960-2024) and predicted total population (2025-2100) for South Korea

(a)

Year	Crude birth rate
1980
2024

Using Figure 1, state the crude birth rate (CBR) of South Korea in 1980 and 2024.

[ 2 ]

Year	Crude birth rate
1980	22.5–23
2024	5

(b)

Using Figure 1, calculate the natural increase rate (NIR) in 1980.

[ 1 ]

(c)

Explain which stage of the demographic transition model South Korea was in during 1980.

[ 2 ]

(d)

Outline two national development policies that might have contributed to the changes in the crude birth rates in South Korea between 1960 and 2024.

[ 2 ]

(e)

Sketch the shape of the age–gender pyramid for 2024 that would lead to the predicted total population changes from 2024 to 2100, as shown in Figure 1.

[ 2 ]

[Maximum number: 2]

Population	5157100
Live births	58887
Deaths	38574
Total fertility rate	1.66 children per woman

Table:Population statistics for New Zealand, 2022

(a)

With reference to Figure 6, calculate the crude death rate (CDR) per 1000 people for the year 2022.

[ 1 ]

$\frac{38\,574}{5\,157\,100}\times 1000=7.48$ ; 7.5 (/1000/year);

Note to examiners: Do not accept improper rounding/no rounding.

(b)

Outline how the total fertility rate of New Zealand shown in Figure 6 will influence its future population.

[ 1 ]

[Maximum number: 13]

(a)

Outline the similarities and differences between crude birth rate and natural increase rate.

[ 4 ]

(b)

To what extent can population policies lead to a stable human population?

[ 9 ]

Answers may demonstrate:
- understanding concepts & terminology of population policies; development policies; anti-natalist/pro-natalist; China's one child policy; female emancipation; gender equality; contraception; child benefit/child tax; population pyramids; population momentum; demographic transition; sustainable development; limiting factors; carrying capacity; S-J curves; DTM; demographic tools (CBR, CDR, TFR, DT, NIR);
- breadth in addressing a range of population and development policies and linking them to their impact on the stability of various human populations and comparing their success.
- examples of relevant national & international population policies and their degree of success in stabilising the population;
- balanced analysis comparing various population policies from a range of countries and evaluating the extent to which these policies managed to effectively stabilise the population on which they were implemented.
- a conclusion that is consistent with, and supported by analysis and examples given e.g. Economic incentives and disincentives can be effective in curbing the growth of human populations, but, generally, the most effective means of stabilising growth seems to come naturally with the development of populations, as evidenced by the relatively stable MEDC populations.

Note to examiners: There is a definition in literature of stable population having stable (=constant) demographics, i.e. CBR, CDR, age structure, but also NIR! Thus it contradicts the definition of a stable population as one with a constant population size (CBR = CDR). Do not penalize the former, although, most probably will lead to convoluted analysis. A response should not earn the higher MBs, unless addressing the latter definition.

Marks	Level descriptor
0	The response does not reach a standard described by the descriptors below and is not relevant to the question.
1–3	The response contains: • minimal evidence of knowledge and understanding of ESS issues or concepts • fragmented knowledge statements poorly linked to the context of the question • some appropriate use of ESS terminology • no examples where required, or examples with insufficient explanation/relevance • superficial analysis that amounts to no more than a list of facts/ideas • judgments/conclusions that are vague or not supported by evidence/argument.
4–6	The response contains: • some evidence of sound knowledge and understanding of ESS issues and concepts • knowledge statements effectively linked to the context of the question • largely appropriate use of ESS terminology • some use of relevant examples where required, but with limited explanation • clear analysis that shows a degree of balance • some clear judgments/conclusions, supported by limited evidence/arguments.
7–9	The response contains: • substantial evidence of sound knowledge and understanding of ESS issues and concepts • a wide breadth of knowledge statements effectively linked with each other, and to the context of the question • consistently appropriate and precise use of ESS terminology • effective use of pertinent, well-explained examples, where required, showing some originality • thorough, well-balanced, insightful analysis • explicit judgments/conclusions that are well-supported by evidence/arguments and that include some critical reflection.

Assessment criteria for the 9-mark extended response

[Maximum number: 2]

Figure 1: Crude birth rate, crude death rate, total population (1960-2024) and predicted total population (2025-2100) for South Korea

Year	Crude birth rate
1980
2024

Using Figure 1, state the crude birth rate (CBR) of South Korea in 1980 and 2024.

Year	Crude birth rate
1980	22.5–23
2024	5

[Maximum number: 1]

Population	5157100
Live births	58887
Deaths	38574
Total fertility rate	1.66 children per woman

Table:Population statistics for New Zealand, 2022

With reference to Figure 6, calculate the crude death rate (CDR) per 1000 people for the year 2022.

$\frac{38\,574}{5\,157\,100}\times 1000=7.48$ ; 7.5 (/1000/year);

Note to examiners: Do not accept improper rounding/no rounding.

[Maximum number: 4]

Outline the similarities and differences between crude birth rate and natural increase rate.

[Maximum number: 3]

Figure Age-gender pyramid for South Korea in 1960

Figure Age-gender pyramid for South Korea in 2024

Figure Population of South Korea from 1960 to 2024

(a)

Describe the trend in population numbers between 1960 and 2024, as shown in Figure 1(b).

[ 2 ]

(b)

Using information from Figure 1(a), sketch a line on Figure 1(b) to demonstrate the expected total population between 2024 and 2100.

[ 1 ]

[Maximum number: 2]

Figure:World population growth, 1750–2050

Figure 2 shows world population growth from 1750 to 2050.

With reference to a named example, explain why a national government may choose not to attempt to control the growth of its population.

[Maximum number: 2]

Figure 1: Crude birth rate, crude death rate, total population (1960-2024) and predicted total population (2025-2100) for South Korea

Outline two national development policies that might have contributed to the changes in the crude birth rates in South Korea between 1960 and 2024.

[Maximum number: 2]

Figure 1: Crude birth rate, crude death rate, total population (1960-2024) and predicted total population (2025-2100) for South Korea

Sketch the shape of the age–gender pyramid for 2024 that would lead to the predicted total population changes from 2024 to 2100, as shown in Figure 1.

[Maximum number: 2]

Figure 1: Crude birth rate, crude death rate, total population (1960-2024) and predicted total population (2025-2100) for South Korea

Explain which stage of the demographic transition model South Korea was in during 1980.

[Maximum number: 9]

Human population growth always results in a loss of biodiversity.

Discuss the validity of this statement.

Answers may demonstrate:

Understanding concepts and terminology of factors associated with human growth that influence biodiversity such as pollution, climate change, habitat destruction, hunting, fishing, illegal trade, invasive species, overharvesting, mass extinction, background extinction rates; endangered species, species-based/habitat-based, in situ/ex situ conservation, nature reserves, stewardship; keystone species; flagship species; reserves; zoos; breeding/re-introduction programmes; gene banks; CITES; education/raising awareness etc.

Breadth in addressing and linking: wide range of positive and negative impacts on biodiversity associated with range of human activities linked to population growth.

Examples: examples of species/habitats that have been affected by human population growth/encroachment; examples of species recovery efforts/successes/extinction;

Balanced Analysis evaluating the extent to which human population growth has always led to a reduction of biodiversity and the extent to which conservation efforts have reduced this loss.

A conclusion that is consistent with and supported by analysis and examples given e.g.: Current extinction rates are way above background extinction rates and this is largely due to the impacts from a growing human population. Despite a wide range of partially successful conservation efforts the net rate of biodiversity loss is still increasing.

The following guide for using the markbands suggests certain features that may be offered in responses. The five headings coincide with the criteria in each of the markbands (although ESS terminology has been conflated with 'understanding concepts') This guide simply provides some possible inclusions and should not be seen as requisite or comprehensive. It outlines the kind of elements to look for when deciding on the appropriate markband and the specific mark within that band.

Section B, part (c) markbands
0: The response does not reach a standard described by the descriptors below and is not relevant to the question.

1–3: The response contains:
• minimal evidence of knowledge and understanding of ESS issues or concepts
• fragmented knowledge statements poorly linked to the context of the question
• some appropriate use of ESS terminology
• no examples where required, or examples with insufficient explanation/relevance
• superficial analysis that amounts to no more than a list of facts/ideas
• judgments/conclusions that are vague or not supported by evidence/argument.

4–6: The response contains:
• some evidence of sound knowledge and understanding of ESS issues and concepts
• knowledge statements effectively linked to the context of the question
• largely appropriate use of ESS terminology
• some use of relevant examples where required, but with limited explanation
• clear analysis that shows a degree of balance
• some clear judgments/conclusions, supported by limited evidence/arguments.

7–9: The response contains:
• substantial evidence of sound knowledge and understanding of ESS issues and concepts
• a wide breadth of knowledge statements effectively linked with each other, and to the context of the question
• consistently appropriate and precise use of ESS terminology
• effective use of pertinent, well-explained examples, where required, showing some originality
• thorough, well-balanced, insightful analysis
• explicit judgments/conclusions that are well-supported by evidence/arguments and that include some critical reflection.

[Maximum number: 2]

Table:Demographic data for four countries

Figure 2 shows a table of demographic data for four countries around the world.

Suggest two reasons for the difference in total fertility rate between Country B and Country C.

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Covered syllabus points

Question 1

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Question (b)

Question (c)

Question (d)

Question (e)

Question 2

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Question 3

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Question 7

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Question 13