The demographic transition model [DTM]:
● Demographic transition model = generalised model linking population changes with development changes
overtime
○ Demographic = the study of population structure
○ Transition = change
○ Model = used to represent the real world in a simplified way
● Shows sequence of changes in birth rates and death rates – which affect population growth
○ Birth rate – death rate = population growth (natural increase/decrease)
■ Natural increase = birth rate > death rate
■ Natural decrease = birth rate < death rate
○ Birth and death rates differ → population growth is faster in some countries than others
● Divides population growth for all countries into 5 stages → can be linked to the development of a country
○ Country moves from stage 1 → 5 as it becomes more developed
● Global patterns:
○ LICs = majority found towards end of stage 2
○ NEEs = found in stage 3 (most developed countries)
○ HICs = found in stage 4 or stage 5 (depending on population)
→ The demographic transition model:
STAGE 1: Least developed
○ High birth rate
■ No use of contraception
■ Poor healthcare
● People have many
children due to high
infant mortality rate
■ Some religions encourage
large families
○ High death rate
■ Poor healthcare
■ Famine
■ Low life expectancy
■ Low income
● STAGE 2: Not very developed [LICs]
○ High birth rate
■ Economy is based on
agriculture
■ Child labour
○ Lower death rate
■ Improved healthcare
■ Improved diet
■ Life expectancy increases
● STAGE 3: More developed [NEEs]
○ Lower birth rate
■ Women have more equal
place in society
● More women work
instead of having
children
■ Better education
■ Use of contraception
○ Low death rate
■ Economy changes from
agriculture →
manufacturing
■ Income increases
■ Less child labour
■ Healthcare improves
■ Medical discoveries
■ Improved diet
■ Higher life expectancy
● STAGE 4 + STAGE 5: Most developed [HICs]
○ Low birth rate
■ People want possessions
■ High quality of life
■ Most have dependant
elderly relatives
■ Less money available for
having children
○ Low death rate
■ Good healthcare
■ High income
■ Life expectancy is high
■ Greying population
Population pyramids:
→ Population pyramids = show how many males/females there are in different age groups , in a particular year
● Divided into 5-year age bars
● Population is divided into male/female
● Percentage/number of each age/sex group is given
○ 3 main groups:
■ Young dependant = 0 – 14 years
■ Independent/economically active = 15 – 64 years (working population)
■ Old dependent = > 65 years
● Structure of a population = proportion of people there are in each age group and the balance between M/F
Impacts of rapid population growth on development:
● Can lead to overpopulation = too many people available for limited land/resources
● Symptoms of overpopulation and impact on development:
○ Falling incomes
■ High unemployment
■ Out-migration
■ Low wages
○ Environmental degradation
■ Overgrazing of land (more livestock)
■ Leads to soil erosion
■ Lack of water supplies
○ Reduced health/happiness
■ Malnourishment (insufficient food)
■ Spread of disease
■ Crowded
● Population growth is not the only cause of overpopulation
● Other factors such as famine and political problems contribute
● Every HIC and many NEEs have benefited from population growth over time
○ People provide human resources
■ Human resources = people and their labour power/ingenuity
○ Helps industries → larger workforce