2. Definition
The "Demographic Transition" is a model that
describes population change over time. It is based
on an interpretation begun in 1929 by the
American demographer Warren Thompson, of the
observed changes, or transitions, in birth and
death rates in industrialized societies over the past
two hundred years or so.
By "model" we mean that it is an idealized picture
of population change in these countries. The model
is a generalization that applies to these countries
as a group and may not accurately describe all
individual cases. Whether or not it applies to less
developed societies today remains to be seen.
http://www.uwmc.uwc.edu/geography/Demotrans/demtran.htm
4. Stage One
High birth rate: children necessary
on farms, no reliable contraception
In India, an adult son was all that kept
a widow from falling into destitution
High death rate: poor medical
knowledge, diet, water, sanitation,
drought and disease
6. Stage Two
High birth rate: children on farms, no
reliable contraception
Decreasing death rate: medical
knowledge and diet improves,
increased food production, improved
sanitation and health
Leads to an increase in life
expectancy
Large increase in population
8. Stage Three
Decreasing birth rate:
industrialization, urbanization,
access to contraception, increase in
wages, education of women,
smaller families needed as infant
mortality drops
Decreasing death rate: more
medical advances, clean water,
infant mortality decreases greatly
Population growth begins to level off
10. Stage Four
Low birth rate: children cost money,
contraception widely available,
women gain status and control
Low death rate: advanced medical
services, good living conditions,
increased health education
Some death rates do remain high
because of obesity, low exercise and
aeging populations
Population decline
