1. World Population Problems
Nature of the World Population Problem
Stable population for 8,000 years
Survival precarious for most people
Since 1650 there has been rapid population growth

2. World Population Growth

3. Population variables
Population increases are a function of three variables, i.e. fertility, mortality and migration
Population formula:
Population (now) = Population (then) + (births-deaths) +/- Migration

4. World Population Growth
8,000 BC to 1650 AD = 500 million
1650 AD to 2000 AD = 5.6 billion
50,000 new mouths to feed every year in first period
50,000 new mouths to feed every 6 minutes today.
90 million people added every year today

5. Malthus’ Explanation of Population Growth
Thomas Malthus Essay on Population
Population grows as exponential rate (2,4,8,16,32,64)
Food production grows at arithmetical rate (1,2,3,4,5)
Population increases faster that food production

6. Validity of Malthus’ Predictions
Malthus proved to be poor prophet in 18th and 19th C
Famine, disease, war did not result in decreased world population
Was Malthus premature?
Paul Erlich’s Population Bomb (neo-Malthusian position) vs. Julian Simon’s Population as the Ultimate Resource. (cornucopian position)

7. Neo-Malthusian position
Population growth straining the world’s resources
Destruction of forests for development and/or food production
Energy and mineral consumption taxes resources
Over-fishing
Widening gap between rich and poor
Inadequate development, refugee problems, donor fatigue
Belief in environmental responsibility leading to sustainable growth

8. Cornucopian position
Life expectancy doubled in 20th C (30yrs to 60 yrs)
Global health and productivity expanding
Overpopulation is scare talk of environmentalists
The real issue of poverty not breeding
Technology will solve all human problems
Population growth creates jobs, opens markets, expands opportunities
Ecologists want sustainability; cornucopian economists want economic growth, exploitation of markets and resources

9. Reasons for Rapid Population Growth
The Demographic transition (from high birth rate and high death rate to low birth rate and low death rate)
Population growth is a function of three variables: fertility, mortality and migration
Formula: Population now = Population (then) +/- (births-deaths) +/- migration

10. Demographic Transition
Stage I
Preindustrial economy
High birth rates and high death rates
Stable population that grows slowly
Large number of children who perform useful work in fields
Children provide social security system in old age
Life expectancy low; security dependent on your family

11. Stage II High birth rates with falling death rates
Improvements in public health, sanitation, medicine that prolongs life
Productivity of agriculture improves
Opportunity for alternative employment due to industrial development
Industrialization stimulates urbanization and specialization of labor

12. Stage III Birth rate declines rapidly
Smaller families due to urbanization and demands for education
Children are more of a liability financially and economically
Population growth declines dramatically

13. Stage IV Birth rates and death rates fall
Population stabilizes at lower level
Demand for education high
Modern economy and urban environment make large families less necessary
Governments adopt social security programs