Changes in Population Size » Birth and Death Rates

What you'll learn this session

Study time: 30 minutes

How birth and death rates affect population size
The demographic transition model and its five stages
Factors affecting birth rates in different countries
Factors affecting death rates in different countries
Population policies and their impacts
Case studies of countries with different demographic profiles

Understanding Birth and Death Rates

Birth and death rates are the primary factors that determine how populations change over time. These rates vary significantly between countries at different stages of development and have profound impacts on society, economy and the environment.

Key Definitions:

Birth rate (natality): The number of live births per 1,000 people in a population per year.
Death rate (mortality): The number of deaths per 1,000 people in a population per year.
Natural increase/decrease: The difference between birth and death rates, showing whether a population is growing or shrinking naturally.
Total fertility rate (TFR): The average number of children born to a woman over her lifetime.
Infant mortality rate: The number of deaths of infants under one year old per 1,000 live births.

⊕ Birth Rates

Birth rates tend to be higher in less economically developed countries (LEDCs) and lower in more economically developed countries (MEDCs). The global average birth rate is about 18 births per 1,000 people per year, but this varies from below 10 in countries like Japan and Italy to over 40 in some African nations.

⊖ Death Rates

Death rates have generally declined worldwide due to improved healthcare, sanitation and nutrition. However, they remain higher in LEDCs due to limited access to healthcare, poor sanitation and malnutrition. The global average death rate is about 8 deaths per 1,000 people per year.

The Demographic Transition Model

The Demographic Transition Model (DTM) shows how birth and death rates change as a country develops economically. It helps us understand population growth patterns and predict future trends.

⊞ Stage 1: Pre-industrial

High birth rates (35-40 per 1,000)
High death rates (30-35 per 1,000)
Low population growth
Examples: Historical societies before 1700s

⊞ Stage 2: Early industrial

High birth rates (35-40 per 1,000)
Falling death rates (20-30 per 1,000)
Rapid population growth
Examples: Afghanistan, Niger

⊞ Stage 3: Late industrial

Falling birth rates (20-30 per 1,000)
Low death rates (10-15 per 1,000)
Slowing population growth
Examples: India, Brazil, Mexico

⊞ Stage 4: Post-industrial

Low birth rates (10-15 per 1,000)
Low death rates (10-15 per 1,000)
Stable population
Examples: UK, USA, Australia

⊞ Stage 5: Advanced post-industrial

Very low birth rates (below 10 per 1,000)
Rising death rates (due to ageing population)
Population decline
Examples: Japan, Italy, Germany

Factors Affecting Birth Rates

Birth rates are influenced by a complex mix of social, economic, cultural and political factors. Understanding these helps explain why some countries have high birth rates while others have low ones.

⊕ Factors Leading to High Birth Rates

Limited access to contraception - In many LEDCs, contraceptives may be unavailable, unaffordable, or culturally unacceptable
Agricultural economies - Children provide labour for farming
High infant mortality - Parents have more children to ensure some survive
Limited women's education - Fewer opportunities beyond motherhood
Religious beliefs - Some religions discourage family planning
Children as old-age security - No pension systems mean children care for elderly parents
Early marriage - Longer reproductive period

⊖ Factors Leading to Low Birth Rates

Widespread contraception - Available, affordable and socially acceptable
Women's education and careers - Delayed childbearing and smaller families
High cost of raising children - Housing, education, childcare expenses
Later marriages - Shorter reproductive period
Urbanisation - Children are an economic cost rather than benefit
Social security systems - Less reliance on children for old-age support
Changing social attitudes - Acceptance of childless lifestyle

Factors Affecting Death Rates

Death rates have generally declined worldwide over the past century, but significant disparities remain between LEDCs and MEDCs.

⊕ Factors Leading to High Death Rates

Limited healthcare access - Lack of doctors, hospitals, medicines
Poor sanitation - Contaminated water and food
Malnutrition - Weakens immune system
Infectious diseases - HIV/AIDS, malaria, tuberculosis
Limited education - Poor health awareness
War and conflict - Direct casualties and disrupted services
Natural disasters - Floods, droughts, earthquakes

⊖ Factors Leading to Low Death Rates

Advanced healthcare - Hospitals, specialists, modern treatments
Improved sanitation - Clean water, sewage systems
Nutritious diets - Balanced food intake
Vaccination programmes - Prevention of infectious diseases
Health education - Awareness of healthy lifestyles
Workplace safety - Reduced occupational hazards
Political stability - Consistent provision of services

Case Study: Japan's Ageing Population

Japan has one of the world's lowest birth rates (7.3 per 1,000) and a rapidly ageing population. With a fertility rate of just 1.3 children per woman (well below the replacement level of 2.1), Japan's population is shrinking by about 400,000 people annually.

Causes:

High cost of living and raising children
Long working hours and work culture
Limited childcare options
Traditional gender roles that burden women with housework

Consequences:

Labour shortages affecting economic growth
Increasing healthcare costs
Pension system under pressure
Rural depopulation as young people move to cities

Government responses: Financial incentives for families, improved childcare facilities and attempts to change work culture. Despite these efforts, the birth rate remains low.

Case Study: Niger's High Birth Rate

Niger has the world's highest birth rate (47.5 per 1,000) and fertility rate (7 children per woman). Its population is doubling approximately every 18 years.

Causes:

Early marriage (76% of girls marry before age 18)
Limited access to contraception (only 16% usage rate)
Agricultural economy where children provide labour
Religious and cultural values favouring large families
High infant mortality (children seen as insurance)

Consequences:

Strain on limited resources (water, food, land)
Difficulty providing education and healthcare
Environmental degradation through overfarming
Perpetuating cycle of poverty

Government responses: Family planning programmes, girls' education initiatives and raising the legal marriage age. Progress has been slow due to cultural resistance and limited resources.

Population Policies

Governments implement various policies to influence birth and death rates, depending on whether they aim to reduce, increase, or stabilise population growth.

↓ Anti-natalist Policies (to reduce birth rates)

China's One-Child Policy (1979-2015):

Limited urban couples to one child
Fines for additional children
Free contraception and incentives for compliance
Reduced fertility rate from 6 to 1.6 children per woman
Led to gender imbalance and ageing population

↑ Pro-natalist Policies (to increase birth rates)

Singapore's "Have Three or More" Campaign:

Tax incentives for larger families
Housing priorities for families
Childcare subsidies
Extended maternity leave
Dating services for educated singles
Limited success in raising birth rates

Environmental Impacts of Population Change

Changes in birth and death rates affect population size, which in turn impacts the environment in various ways:

Resource consumption: Larger populations require more food, water, energy and materials
Land use changes: Population growth often leads to deforestation, urbanisation and agricultural expansion
Pollution: More people typically means more waste, emissions and environmental contamination
Biodiversity loss: Habitat destruction from human expansion threatens plant and animal species
Climate change: Population size affects carbon emissions, though per capita consumption in wealthy countries is a major factor

However, the relationship between population and environmental impact is complex. A smaller population with high consumption patterns can cause more environmental damage than a larger population with sustainable practices.

Summary

Birth and death rates are fundamental drivers of population change. They are influenced by a wide range of social, economic, cultural and political factors that vary across countries and over time. The Demographic Transition Model helps us understand how these rates change as societies develop economically.

Most LEDCs have high birth rates and declining death rates, leading to rapid population growth. Most MEDCs have low birth and death rates, resulting in slow growth or even population decline. These demographic patterns create different challenges for different countries, from resource pressures in fast-growing populations to ageing issues in shrinking ones.

Understanding these patterns helps us develop appropriate policies to address population-related challenges and work toward sustainable development that balances human needs with environmental protection.

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