Demographic Transition Model

Population increase= Natural increase + rate of net migration

These changes are analyze in a Demographic Transition Model

There are 4 stages in the model

• The Demographic Transition Model attempts to show how population changes as a country develops in terms or BR, DR, & pop growth

• The model is divided into four stages.

• The Demographic Transition Model does not take into account migration.

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

Examples • Tribal societies in remote areas

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.

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

Examples• Niger, Afghanistan

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

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

Example• Malaysia, Mexico

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.

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)

Example• USA, France

Stage 4: Pyramid Structure

• Birth rates and death rates are low; as fertility continues to decline, an AGING SOCIETY emerges.

• Pyramid seems to “invert”

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

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.