Question:
Analyse the role of demographic transition theory in explaining variation in fertility and mortality rates globally
(UPSC 2025, Paper 1, Geography Optional PYQ)
Answer.
The Demographic Transition Theory (DTT) is one of the most important models in population geography. It explains how fertility rates (birth rates) and mortality rates (death rates) change over time as societies move from traditional agrarian economies to modern industrial and urban societies.
DTT theory was proposed by Warren Thompson (1929) and later refined by Frank Notestein. The theory helps explain global differences in population growth patterns.
It links population change with:
- Economic development
- Urbanization
- Education
- Healthcare
- Industrialization
The Five Stages of Demographic Transition
Stage 1: High Stationary
- High birth rate + High death rate
- Low population growth
- Poor healthcare, famine, disease
Example: Pre-industrial societies
Stage 2: Early Expanding
High birth rate + Rapid fall in death rate
Population explosion
Reasons:
- Medical improvements
- Better sanitation
- Food security
Example: Many African countries today
Data: Sub-Saharan Africa fertility rate ≈ 4.5 births per woman (UN 2023)
Stage 3: Late Expanding
Falling birth rate + Low death rate
Population growth slows
Reasons:
- Urbanization
- Women’s education
- Family planning
Example: India, Brazil
India fertility rate: 2.0 (NFHS-5, 2021)
Stage 4: Low Stationary
- Low birth rate + Low death rate
- Stable population
Example: USA, France, UK
Stage 5: Declining Stage
- Very low birth rate
- Aging population
Example: Japan, Germany
Japan's fertility rate: 1.3 births per woman (As per the World Bank)
Role of DTT in Explaining Global Variations in Fertility
The following are the roles of the Demographic Transition Theory in explaining Global variations in fertility:
1. Economic Development Differences
DTT shows that fertility declines as:
- Income increases
- Education improves
- Urbanization rises
Example:
- Niger fertility rate: 6.7
- South Korea's fertility rate: 0.7
2. Role of Women’s Education
Higher female literacy leads to:
- Delayed marriage
- Smaller families
Example:
Kerala's fertility rate = 1.6, due to high female literacy.
3. Urbanization Influence
Urban lifestyles increase:
- Cost of raising children
- Women's workforce participation
This reduces fertility.
4. Cultural and Social Factors
DTT helps explain differences due to:
- Religion
- Social norms
- Family values
Example:
- Middle East countries still have higher fertility despite economic growth.
Role of DTT in Explaining Mortality Variations:
The following ways the Demographic Transition Theory explains Mortality Variations:
1. Medical Technology
Decline in mortality linked to:
- Vaccination
- Antibiotics
- Public health
Example: Global life expectancy rose from 46 years (1950) to 73 years (2023).
2. Nutrition and Food Security
Better food supply reduces death rates.
Example: The Green Revolution reduced mortality in India.
3. Healthcare Infrastructure
Countries in advanced stages have:
- Low infant mortality
- High life expectancy
Example:
- Japan life expectancy = 84 years
- Nigeria life expectancy = 54 years
Criticisms of Demographic Transition Theory
Despite its usefulness, Demographic Transition Theory has several criticisms:
- It is an Eurocentric Model based mainly on Western experience.
- It Ignores Migration, which significantly affects population change.
- Cultural differences are not fully explained in the theory. Some developed countries still have high fertility due to social norms.
- It does Not Predict Future Trends; Example: Many countries now face population decline, which was not originally included. Phase 5 of the demographic transition theory was later included.
Despite the above criticism, the Demographic Transition Theory is quite acceptable. The following are the contemporary Relevance of the theory.
Today, DTT is widely used in:
- Population planning
- Development studies
- Policy making
- Economic forecasting
It helps understand:
- Aging populations
- Population explosion
- Workforce challenges
Demographic Transition Theory remains a powerful framework for explaining global variations in fertility and mortality rates. It effectively links population change with economic and social development. However, its limitations in accounting for cultural diversity, migration, and modern demographic complexities mean that it should be applied alongside other population theories for a comprehensive understanding.
You may also:
ConversionConversion EmoticonEmoticon