Population Theories

Theory of Demographic Transition Demographic Transition-The phenomenon of population changes in a country over time

Stage 1 Pre-Transition High, stable birth rate High, fluctuating death rate No natural increase Rural/Agricultural society No countries in the world are at this stage

Stage 2-Early Transition High birth rate Falling death rate-“Germ Theory of Disease Control” Large natural increase Rural/Agricultural society

Stage 3-Late Transition Falling birth rate (birth control) Low death rate Decreasing natural increase Urban/Manufacturing society

Stage 4-Post Transition Low birth rate Low death rate No natural increase Urban/Service sector based society

Stage 5?? Post-Post Transition? Death rate>Birth rate= Natural Decrease

Pessimistic Views-Thomas Malthus (1766-1834) Political economist who recorded concerns about changes occurring in Europe in the early nineteenth century -Europe at the time was entering a period of rapid industrialization, but also very rapid population growth. -According to Malthus, the population appeared to be growing in a geometric sequence (1,2,4,8,16…)- too quickly for the food supply which could only increase arithmetically (1,2,3,4…) .He felt that population, if uncontrolled, would be "checked" by certain things: "Positive" Checks 1. Disease-"The Black Death" 2. War-Napoleon, Crusades... 3. Famine-India "Negative" Checks -predicted that mankind would consciously prevent births through: 1. Choice 2. Delayed marriage

Present Day "Positive" Checks 1. Aids, Ebola 2. Africa’s situation (Life expectancy-38 years) Malthus could never have predicted: -Global access to medicine, water, food -Widespread birth control -Global awareness -Fear of nuclear destruction

William Catton Introduced the concept of the earth’s carrying capacity He suggests that the earth has been exceeding its carrying capacity for many years; this has been possible because we have been using up non-renewable resources that future generations will need This is known as a “phantom carrying capacity”-while allowing a higher population, is ultimately non-sustainable and the economic and ecological systems will collapse

Optimistic Views Cornucopians-have faith in the human ability to find technological innovations that will increase the earth’s carrying capacity D.J. Bogue-Theory of Demographic Regulation-over an extended period of time, a society naturally limits its population. The population will grow only in response to the Earth’s ability to support it.

Population Cartogram