1. Population Pyramids: Shapes
Shape: Extended Triangle
Growth: Moderate
Shape: Triangular
Growth: Fast
Shape: Column
Growth: Slow
Shape: Reduced Pentagon
Growth: Shrinking
Session 4

2. Malthus and Overpopulation
Thomas Malthus – 1798 wrote “Essay on the Principle of Population”
Theory:
People need food to survive and have natural desire to reproduce
Food production increases arithmetically and population increases exponentially
Conclusion:
Predicted population growth would eventually outpace people’s ability to produce food leading to mass starvation and famine
Malthus and Overpopulation
Time
Resources Needed
Today
1 person-1 unit of food
25 years from now
2 persons-2 units of food
50 years from now
4 persons- 3 units of food
75 years from now
8 persons- 4 units of food
100 years from now
16 persons-5 units of food
Session 4

3. Paul Erlich – most prominent neo-Malthusian. Wrote “Population Bomb”
Neo-Malthusians argue that 3 characteristics of recent population growth makes Malthus’ argument even more frightening
Sustainability: As the world approaches 10 billion people, ecological problems will make food demand difficult to meet
Increasing Per Capita Demand: Amount of food per person is rising MDC citizens consume eight times the amount someone in an LDC consumes
Natural Resource Depletion: Over- consumption of resources other than food may lead to an insufficient supply when the population hits 10 billion
Neo-Malthusians
Paul Erlich – most prominent neo-Malthusian. Wrote “Population Bomb”
Session 4

4. Malthus and Overpopulation
The disastrous end to humanity predicted by Malthus did not occur according to his critics for the following reasons:
Invention: Food production increased because of tractors, artificial fertilizer, pesticides, irrigation techniques, plant and animal hybridization, refrigeration and canning
Family Planning: Malthus did not foresee family planning and birth control and leading to a drop in CBR and NIR
Scarcity/Distribution: Malthus did not recognize that famine is usually NOT related to a lack of food but to unequal distribution of food
Malthus and Overpopulation
Session 4

5. Carrying Capacity: The number of people a given area can maintain
If surpassed, the population must decline unless the carrying capacity is raised.
Overpopulation, therefore, implies a breach of an area’s carrying capacity, due to…
Over consumption of resources
Inefficient allocation of goods
Unsustainable land use
MDC’s blame LDC’s for having too many babies while LDCs blame MDCs for consuming disproportionate share of world’s resources
Carrying Capacity
Session 4

6. Epidemiological Transition Model
The stages of the Epidemiological Transition Model follows the same path as the Demographic Transition Model.
Stage 1: Pestilence and Famine
Infectious diseases run rampant killing a large number of the population
Stage 2: Receding Pandemics
Improved sanitation, nutrition, medicine decreases spread of infectious diseases
Stage 3: Degenerative and Human Created Diseases
Fewer deaths from infectious diseases but an increase in chronic disease associated with aging (heart disease and cancer)
Stage 4: Delayed Degenerative Diseases
Degenerative diseases linger but life expectancy is extended through medical advances (bypass, radiation, chemo, etc.)
Stage 5?: Reemergence of Infectious and Parasitic Diseases
Evolution of new strains of bacteria (TB, polio, malaria) that are diffused faster due to globalization with a select few able to pay for the treatment
Epidemiological Transition Model
Session 4

8. Video China’s Lost Girls 2 Directions:
There is no video guide, but students are expected to write down 5 impressions and/or questions that they have from the documentary.
China’s Lost Girls
Video
Session 2