The document discusses the Demographic Transition Model, which attempts to show how population changes as a country develops. The model divides development into four stages: Stage 1 has high birth and death rates, leading to low population growth. Stages 2 and 3 see birth rates remain high while death rates fall dramatically, resulting in rapid population increase. Stage 4 is characterized by low birth and death rates, leading again to low population growth. The model shows these stages through a country's population pyramid shape. However, the model is an overgeneralization and does not consider exceptions like war or political issues.

1. Definitions
• Infant Mortality: It is defined as the
proportion of children who die before they
reach the age of one year
• Life Expectancy: It is the number of years that
a child born in a particular country in a
certain year can expect to live

2. Demographic Transition
Model
Population increase=
Natural increase + rate of net migration
These changes are analyze in a
Demographic Transition Model

3. There are 4 stagesin the model
• The Demographic Transition Model attempts to
show how population changes as a country
develops.
• The model is divided into four stages.
• The Demographic Transition Model does not take into account migration.

5. The Four Stages
Stage 1
• Birth rate is high
• Death rate is high
• Low natural increase - low total population
Factors
• Children provide security & Labor
• Religious beliefs encourages large families
• poor or inadequate medical care & sanitation
Give Examples?

6. Stage 1: Pyramid Structure
•Due to high birth rates, the pyramid shape would have a wide
base;
•Due to high death rates, the pyramid would be very short in
height; concave shape indicates low life expectancy.

7. The Four Stages
Stage 2
• Birth rate is high –
• death rate is falling –
• high natural increase (population growth)
Factors
• Birth rates high because of cultural factors
• Advances in medical care and sanitation
Give Examples?

8. Stage 2 : Pyramid Structure
• As death rates fall, the population explosion begins;
• The height of the pyramid grows to reflect the
prevention of more deaths; shape becomes less
concave as life expectancy increases;
• The width of the base remains large due to the
ongoing high birth rates

9. The Four Stages
Stage 3
• Falling birth rate
• Low death rate
• High natural increase
(population growth)
• The “gap” closes, population increase slows down
Factors
• Realization-large families are unnecessary
• Family planning becomes available
• Parents favor material things, not large families,
• Woman become more involved in the workforce
Give Examples?

10. Stage 3: Pyramid Structure
• As birth rates begin to be addressed, the base begins to
stabilize and eventually narrow;
• Death rates are low and stabilized, meaning that the
pyramid continues to grow higher.

11. The Four Stages
Stage 4
• Birth rate is low
• Death rate is low
• low natural increase - high total population
• Small “gap” like in stage 1
(Population may be declining)
Give Examples?

12. Stage 4: Pyramid Structure
• Birth rates and death rates are low; as fertility continues
to decline, an AGING SOCIETY emerges.
• Pyramid seems to “invert”

13. MEDC vs. LEDC
Note the quick transition to Phase
3 from the explosion of Phase 2
Note the longer time period as
LEDC’s are “trapped” in Phase 2

14. Criticism of DTM
• The model is an over-generalization of the industrialized
European experience
• Industrialization is difficult to achieve for LEDC’s in a
trading system that protects the industries of MEDC’s;
• Model assumes all countries proceed from stage 1-4;
• It ignores variables and exceptions (ie. War, political turmoil)
• The model assumes that reductions in fertility are a
function of increased wealth and industrialization–
• Other factors such as the status of women and other social
development are ignored.