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Population

Population. In the last 200 years the population of our planet has grown exponentially, at a rate of 1.9% per year. If it continued at this rate, with the population doubling every 40 years, by 2600 we would all be standing literally shoulder to shoulder.  -- Professor Stephen Hawking.

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Population

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  1. Population In the last 200 years the population of our planet has grown exponentially, at a rate of 1.9% per year. If it continued at this rate, with the population doubling every 40 years, by 2600 we would all be standing literally shoulder to shoulder. -- Professor Stephen Hawking

  2. Population Geography • Distribution of World Population • Population Statistics • Population Pyramids • Demographic Transition Theory • Population Control • Overpopulation (Malthus and Neo-Malthusians)

  3. Population Density • Arithmetic Density Total population/Total Land area • U.S. = 76/mi2; NYC=1,000,000/mi2; Australia = 7/mi2 • Physiological Density Total population/ Total Farmable land • 95% of Egyptians live near the Nile river • Agricultural Density Total farmers/Total farmable land • High-most people are farmers Low-not many farmers needed

  4. World and Country Population Totals Distribution and Structure: 3/4 of people live on 5% of earth's surface! Total: 7 billion on planet as of Oct. 31, 2011 http://www.worldometers.info/world-population/ Five most populous regions and countries REGION POPULATION COUNTRY POPULATION • East Asia 1.5 billion China 1.387 billion • South Asia 1.2 billion India 1.254 billion • Europe 750 million U.S. 320 million • SE Asia 500 million Indonesia 250 million • East N. Am.120 million Brazil 200 million

  5. NIR Formula CBR – CDR=NIR Example: 20 (CBR)-5 (CDR)=15 per 1,000 or 1.5% ALWAYS EXPRESSED AS A PERCENT!!!

  6. Rates of Natural Increase

  7. Total Fertility Rate TFR- the average number of children a women will have in her childbearing years. This rate varies from just over 1 (Japan, Italy) to around 7 (Niger, Mali). The U.S. rate is 2. 2.1 is generally regarded as the replacement rate (the rate at which a population neither grows nor shrinks) in the developed world. In less developed countries this rate should be higher to account for so many children not reaching childbearing age.

  8. Infant Mortality Rate IMR– the number of deaths of children under the age of one per thousand live births. The rate ranges from as low as 3 (Singapore, Iceland) to as much as 150 (Sierra Leone, Afghanistan). The U.S. rate is just over 6. High infant mortality tends to result in higher fertility rates as families seek “insurance” for the loss of children.

  9. Family Planning Programs • One family/one child policies • Sterilization • Increased taxes • Loss of social status • Termination healthcare/food coupons • Free birth control • Increased literacy and education to stop unwanted births

  10. Demographic Transition Model • Developed in 1929 by American demographer Warren Thompson • Using demography statistics, level of industrialism and economic wealth, each country is placed into stages • Most countries are currently in Stage 3 or higher • The exception would be Sub Saharan, parts of the Middle East and Asia • The model is growing outdated as countries reach the end of stage 4

  11. Demographic Transition Model

  12. DTM Stages • Stage one (preindustrial/pre-agricultural) • Crude birth/death rate high • Several spikes and drops in CBR/CDR • Stage two (improved agriculture and medicine) • Lower death rates • Infant mortality rate falls • Natural increase very high • Stage three (Social change) • Indicative of richer developed countries • Higher standards of living/education • Crude birth rate finally falls • Stage four • Crude birth/death rates low • Population stable • Populations aging

  13. DTM Possible Stage 5 • Most of the highly developed countries are exhausting the 4th stage • Demographers are now starting to theorize a 5th and possible 6th stage of Thompson’s model • Very low CBR, CDR and a total population decline in a country • Replacement rate is not being met and the country is declining in population (does not account for migration) • These countries are highly industrialized, high levels of education and equality • Any population increase would be due to immigration and not citizens having kids

  14. 3 reasons for stage changes

  15. Why a country changes from stage 2 to stage 3

  16. Weakness of the DTM • It is only a model • Becoming increasingly outdated as countries reach stage 4 • New geographical studies suggest that fertility decline doesn’t have to be connected to increased wealth • As well as an increase in fertility in highly wealthy countries • The model does not account for immigration in each country • Immigrants tend to have higher TFR than citizens

  17. Population Pyramids • Bar graph that displays demography data • Pyramids show • Age -Young vs Old • Gender- Male vs Female • Dependency Ratio- Number of population under 15 and over 65 • Stage 2 countries have a dependency ratio of 1:1 • 10:1 for younger dependants • Stage 4 countries have a dependency ratio of 2:1 • Elderly and young are roughly equal. More than ¼ government expenditures are on the elderly in stage 3 and 4 countries • Women outnumber men in most MDCs • Countries with high immigration have more males • Retirement communities have more women than men • Population Pyramids are effected by ethnic compositions

  18. 4 3 5 2 1

  19. Analysis of Italy’s Population Pyramid • 1. Decline in Birth Rate • 2. Baby Boom • 3. Fewer men due to World War I and II • 4. More women due to: a. longer life expectancy and b. World Wars (I and II) • 5. More 75-79 yrs than 0-4 yrs. Signs of a future worker shortage and an overall declining population.

  20. Thomas Malthus on Population An Essay on the Principle of Population, 1798 Malthus predicted population would outrun food supply, leading to a decrease in food per person. Assumptions • Populations grow exponentially. • Food supply grows arithmetically. • Food shortages and chaos inevitable.

  21. Neo Malthusians People who support Malthus’ original hypothesis but tweaked the theory • Malthus failed to include LDCs in his theory • LDCs entered stage 2 not because of wealth but because of medical revolution • Overpopulation affects not just food production but also other resources • Population will continue to rise in LDCs therefore people will be fighting over resources not just food

  22. Critics of Malthus • Possibilism allows for humans to change environment • Larger population stimulates economic growth and ideas • Marxists believe poverty and hunger are a result of unjust social institutions • Higher population for national defense (armies) • Capitalism creates unequal access to resources

  23. Epidemiological Transition • Created by Abdel Omran in 1971 • Follows the DTM but looks at the health threats of each stage • Explains the CDR of each stage • Later the model was modified for stage 4 by Olshansky and Ault • The modification was to take into account the impact of medical advances that keep people alive

  24. Epidemiological Transition • Stage 1 Pestilence and famine • High CDR • Black Plaque • Stage 2 Pandemics • Rapidly declining CDR • Cholera • Controlled with improved sanitation • Stage 3 degenerative diseases • Moderately declining CDR • Cardiovascular disease, heart attacks • Stage 4 (delayed stage 3) • Low but increasing CDR • Life expectancy was longer due to medical advances • Possible stage 5 reemergence of stage 1 (infectious and parasitic diseases) • Mutation of diseases • poverty decreases sanitation • increased travel to spread new contagions like Malaria, TB and SARS

  25. Population Futures • Two ways to lower CBR • Increased economic development provides better education and health care • Improve a country’s economy • Increase country’s literacy rate • Increase girls’ access to education and jobs • Increased health care to lower IMR • Distribution of contraceptives and education about family planning • Sexual education • Access to birth control (contraceptives) • Bangladesh, Colombia, Morocco and Thailand have low literacy rates but access to birth control • 25% of women in sub Saharan Africa use contraceptives

  26. Summary • Overpopulation is a relationship between the size of the population and a region’s level of resources • CBR must be reduced in order to curb global population growth • Countries experience different population and epidemiological transitions • Malthus was only partly correct • LDCs increasing populations make up for MDCs declining populations

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