Demographic Transition Model (DTM) and Epidemiological Transition Model (ETM)

Overview

• Purpose: To understand patterns of population growth and decline throughout history.
• DTM: Explains how birth and death rates change in relation to a country's development from agrarian to industrial.
• ETM: Explains demographic transition through the lens of disease and death rates.

Demographic Transition Model (DTM)

Stages of DTM

1. Stage 1: High Stationary Stage

   • Pre-industrial society.
   • High birth and death rates, cancel each other out.
   • Population remains stable.
   • No current countries in this stage.

2. Stage 2: Early Expanding Stage

   • Beginning of industrialization.
   • High birth rate, declining death rate.
   • Population explosion due to technological and medical advancements.
   • Example: Sub-Saharan Africa.

3. Stage 3: Late Expanding Stage

   • Continued industrialization, economic growth.
   • Birth rates decline, but population continues to grow slowly.
   • Many developing nations are here.

4. Stage 4: Low Stationary Stage

   • Fully industrialized society.
   • Birth and death rates are low and close to each other.
   • Population stabilizes.
   • Concerns about aging population and elderly care.
   • Most developed nations are in this stage.

5. Stage 5: Natural Decrease Stage (recent addition)

   • Birth rate falls below death rate.
   • Population begins to decline.
   • Example: Japan.

Limitations of DTM

• Focuses only on birth and death rates, ignoring migration.
• Developed to explain Western population trends; may not apply globally.

Epidemiological Transition Model (ETM)

Stages of ETM

1. Stage 1: Famine Stage

   • High death rate due to infectious diseases, poor nutrition, etc.
   • Low life expectancy.
   • Population growth is infrequent and unsustained.

2. Stage 2: Receding Pandemic Stage

   • Improved sanitation and nutrition.
   • Death rates decrease significantly.
   • Life expectancy increases to ~50 years.
   • Still high pandemic risks due to urbanization.

3. Stage 3: Degenerative and Human-Created Disease Stage

   • Further increase in life expectancy.
   • Deaths primarily from aging-related diseases like heart disease.

4. Stage 4: Delayed Degenerative Disease Stage

   • Highest life expectancy due to medical advancements against diseases.
   • Effective treatments for previously fatal conditions.

5. Stage 5: Re-emergence of Infectious Disease Stage

   • Infectious diseases return, resistant to drugs and antibiotics.
   • Decrease in life expectancy.

Limitations of ETM

• Oversimplifies demographic change, focusing only on death rates and disease.
• Does not account for poverty as a major factor in disease spread and life expectancy.

Conclusion

• Both models offer frameworks for understanding demographic changes.
• Important to recognize their limitations and the complex factors influencing population dynamics.

Additional Resources

• AP Human Geography Heimler Review Guide for further study and exam preparation.