Chapter 2: Population

1. Chapter 2: Population http://www.ted.com/talks/hans_rosling_on_global_population_growth.html

2. Why is Population Increasing at Different Rates?Demographic Transition Model Figure 2-15

3. Demographic Transition • Countries that don’t fit the model: negative growth (Ukraine) • Applicability of the demographic transition to developing populations • Different economic situations • No migration escape hatch for LDCs (“massive exodus” from Europe during the 19th century) • LDC populations are larger, denser, faster-growing • Hidden momentum of young age-sex pyramids

4. Demographic Momentum (hidden momentum) • Occurs in an age structure with a large base and small top • Very few elderly at the top of pyramid are available to die • Many children who will soon be in peak reproductive ages (reproducing age 19-49) • Compare the large number of children being born to the small number of elderly dying

5. Overpopulation, Malthus, and Neo- Malthusians “The capacity of Earth to produce food and support people is finite.” - Anne & Paul Erlich

6. Thomas Robert Malthus • British political economist, demographer and Reverend • Wrote An Essay on the Principle of Population in 1798 (his views on effect of population on food supply) http://www.youtube.com/watch?v=r1ywppAJ1xs&feature=player_embedded

7. Malthus’ Theory of Population Growth • Population grows at a geometric rate i.e. 1, 2, 4, 16, 32, etc. • Food production increases at an arithmetic rate i.e. 1, 2, 3, 4, etc.

8. Malthus (cont.) • The consequence of these two principles is that eventually, population will exceed the capacity of agriculture to support the new population numbers. Population would rise until a limit to growth was reached. Further growth would be limited when: • preventive checks - postponement of marriage (lowering of fertility rate), increased cost of food etc. • positive checks - famine, war, disease, would increase the death rate.

9. Malthus (cont.) Population grows geometrically…. Population exceeds carrying capacity… Population is kept in “check”– preventative and/or positive checks

10. The “Malthusian crisis” • Available agricultural spaces are limited. • Technical progresses (machinery, irrigation, fertilizers, and new types of crops) are slow to occur. • Increasing incapability to support the population. • If this persists, the population will eventually surpass the available resources. • The outcomes are “Malthusian crises”: • Food shortages, Famines, War and epidemics.

11. The Malthusian Crisis Has Not Occurred • Malthus has been criticized on several accounts during the last 200 years. • Religious view (Protestantism), racist and elitist. • Malthus did not foresee cultural/economic factors that bring countries to Stage 3 and 4 of demographic transition (industrialization and the role of children, social customs and women in workforce, birth control, etc.)

12. Criticisms of Malthus • Malthus did not account for technological advancements that could increase food output • Enabled food production to increase at rates greater than arithmetic, often at rates exceeding those of population growth. • Enabled to access larger amounts of resources. • Malthus over-predicted the population growth

13. India’s Recent Experience Figure 2-25

14. Criticisms of Malthus • Marxist critique – social problems result from unjust economic structure, not population problems • Engels critique – Malthus’ theory was based on capitalism, if resources were shared equally, earth could sustain a much larger population

15. Esther Boserup’s Theory of Population Growth • Boserupemphasized the positive aspects of a large population; • In simple terms, Boserup suggested that the more people there are, the more hands there are to work; • She argued that as population increases, more pressure is placed on the existing agricultural system, which stimulates invention; • The changes in technology allow for improved crop strains and increased yields.

16. Neo-Malthusians • Share Malthus’ concern for population growth • Argue that Malthus thought only wealthy countries would enter periods of high population growth (Stage 2 of DTM) • Argue world population growth is outpacing many resources, not just food

17. Video

18. Began with this statement… • The battle to feed all of humanity is over. In the 1970s hundreds of millions of people will starve to death in spite of any crash programs embarked upon now. At this late date nothing can prevent a substantial increase in the world death rate ...

19. Basically …..humanity could not prevent severe famines, the spread of disease, social unrest, and other negative consequences of overpopulation.

20. The Population Bomb • Published in 1968 • Launched worldwide debate and spurred along environmental movement • Was received with much skepticism about its argument and predictions • In 1968 world population was 3.5 billion, 40 years later it was 6.7 billion

23. What it got right…. • Drew attention to the “over-consumption problem” • Expressed concern over the seas’ bounty • Predicted high-yield grains were best option for meeting the world’s hunger • Expressed concern over the environmental effects of the “Green Revolution” • Predicted threats of new epidemics

24. What it got wrong… • Did not account for the number of and increase in greenhouse gas emissions • Too optimistic about consumption: while population nearly doubled, consumption nearly tripled • Underestimated environmental impact of “Green Revolution” • Incorrectly predicted that the Baby Boomers would continue high birth rates of their parents

26. Why Do Some Regions Face Health Threats? • Epidemiologic Transition • Medical researches have identified an epidemiologic transition that focuses on distinct health threats in each stage of the demographic transition. • Stage 1: Pestilence and Famine (High CDR) • Principal cause of death: infectious and parasitic diseases • Ex. black plague (bubonic plague)

27. Stage 2: Receding Pandemic (Rapidly Declining CDR) • Pandemic is a disease that occurs over a wide geographic area and affects a very high proportion of the population. • Factors that reduced spread of disease, during the industrial revolution • Improved sanitation • Improved nutrition • Improved medicine • Famous cholera pandemic in London in mid nineteenth century.

28. Figure 2-31

29. Stage 3: Degenerative Diseases (Moderately Declining CDR) • Characterized by… • Decrease in deaths from infectious diseases. • Increase in chronic disorders associated with aging. • Cardiovascular diseases • Cancer • Stage 4: Delayed Degenerative Diseases (Low but Increasing CDR) • Characterized by… • Deaths caused by cardiovascular diseases and cancer delayed because of modern medicine treatments.

32. Infectious Diseases • Reasons for Possible Stage 5 • Evolution • Infectious disease microbes evolve and establish a resistance to drugs and insecticides. • Antibiotics and genetic engineering contributes to the emergence of new strains of viruses and bacteria. • Poverty • Infectious diseases are more prevalent in poor areas because of presence of unsanitary conditions and inability to afford drugs needed for treatment. • Increased Connections • Advancements in modes of transportation, especially air travel, makes it easier for an individual infected in one country to be in another country before exhibiting symptoms.

33. The Most Lethal Infectious Disease: AIDS Figure 2-33

35. Why Do Some Regions Face Health Threats? • Health Care • Health conditions vary around the world, primarily, because countries possess different resources to care for people who are sick. • Expenditures on Health Care • More than 15 percent of total government expenditures in Europe and North America. • Less than 5 percent in sub-Saharan Africa and South Asia.

36. Health Care Systems • Developed Countries • Public service available at little or no cost. • Government pays more than 70 percent of health-care costs in most European countries, and private individuals pay about 30 percent of the expense. • Developing Countries • Private individuals must pay more than half of the cost of health care. • U.S. is an exception to these generalizations, because private individuals are required to pay about 55 percent of health care costs making it more closely resemble a developing country, in regards to health care.

41. Summary • Global population is concentrated in a few places that are not too wet, too dry, too cold, or too mountainous. • Nearly all NIR is concentrated in developing countries. • Developed countries have a stable population, if not slightly declining. • Population growth varies among regions, because not all countries are in the same stage of the demographic transition model.

42. Summary • Intimately connected to the demographic transition model is the epidemiologic transition model that helps to explain why different regions face varying health threats.