Demographic Transition Model

Stage ONE: Little to No Growth

• CBR = CDR

• Short life expectancy, high infant mortality

• Disease, lack of health care, poor sanitation

• US/Europe: before late 18th

• Almost no countries now in Stage 1

Stage TWO: Rapid Growth

• Death rates decline

• Improved health care, access to water & food, vaccinations

• Fertility rates remain high

• Imbalance

• US early 19th, India now

Stage THREE: Stable Growth

• Economy/Education improves

• Family income up, #births declines

• More birth control availability

• CBR lowers to = CDR again

Stage FOUR: Stable Growth

• CBR < CDR

• High affluence/economic development

• More elderly

• Govt may encourage immigration or $$ incentives to have more children

Stage FIVE: Declining Growth?

• very low birth rate

• low death rate

• slow decrease of the total population

Affluence

• More resources used per person

• More wealth (higher GDP) can lead to environmental improvements and increased efficiency

Technology

• Destructive: New toxic chemicals, increased resource extraction, manufactured “needs”

• Beneficial: Green solutions that increase efficiency and lower impact (hybrid car)