1. © 2011 Pearson Education, Inc. Unit 2: Population & Migration Where do people live and how did they get there?

2. © 2011 Pearson Education, Inc.  Chapter 2 looks at Population ◦ Demography: Geographic word for defining where people live and how are they distributed according to age, gender, occupation, fertility, health, etc.  Chapter 3 focuses on Relocation diffusion ◦ Migration is a specific kind of relocation diffusion where people move permanently from one place to another  Why are these topics crucial and relevant? ◦ 1 More people are alive at this time than at any other point in history (over 7 Billion) ◦ The greatest population growth is happening in LDCs (Less Developed Countries) ◦ The changing scale generated by modern transportation systems makes migration more feasible than in the past ◦ MDCs (More Developed Countries) are experiencing increased rates of immigrants, both legal and illegal

3. © 2011 Pearson Education, Inc. Population Concentrations Sparsely Populated Regions Population Density

4. © 2011 Pearson Education, Inc. Where Is the World’s Population Distributed?  Population concentrations ◦ Two-thirds of the world’s population are in four regions: 1.East Asia: ¼ of the World’s Population live here – 5/6s of the people in this concentration live in China, the most populous country. 2.South Asia: Nearly ¼ of the world’s population live here as well, in India, Pakistan, Bangladesh, and Sri Lanka. India has 3/4s of the population in this concentration 3.Europe: Including Russia, this is the 3 rd largest concentration of people in 4 dozen countries 4.Southeast Asia: World’s 4 th largest concentration with 6 million people on the various islands between the Indian Ocean and the Pacific

5. © 2011 Pearson Education, Inc. Population Distribution Fig. 2-2, p. 48 Figure 2-2

6. © 2011 Pearson Education, Inc. Where Is the World’s Population Distributed?  The Ecumene ◦ From the Greek: “The inhabited Universe” ◦ Today’s usage: Environments where World Civilizations have settled  Sparsely populated regions ◦ People generally avoid:  Dry lands  Wet lands  Cold lands  High lands

7. © 2011 Pearson Education, Inc.  The Portion of the earth occupied by permanent human settlement  It has expanded from the Middle East and East Asia to encompass most of the world’s land area Figure 2-4

8. © 2011 Pearson Education, Inc. Where Is the World’s Population Distributed?  Population density ◦ Arithmetic density: total number of objects in an area (Ch. 1) also: Total number of people divided by land area (Ch. 2) ◦ Physiological density : regionally, total number of people supported by a unit of arable land ◦ Agricultural density: ratio of numbers of farmers to the amount of arable land

9. © 2011 Pearson Education, Inc. Measures of Density Table 2-1

10. © 2011 Pearson Education, Inc. Natural Increase Fertility Mortality

11. © 2011 Pearson Education, Inc. Where Has the World’s Population Increased?  Natural increase rate ◦ The percentage by which a population grows in a year  Crude birth rate (CBR) ◦ The number of births per 1,000 population  Crude death rate (CDR) ◦ The number of deaths per 1,000 population  Doubling time ◦ The number of years needed to double a population

12. © 2011 Pearson Education, Inc. World Population Growth Figure 2-8

13. © 2011 Pearson Education, Inc. Where Has the World’s Population Increased?  Fertility ◦ Total fertility rate (TFR) measures the total births in a society. (Average number of children a woman will have through her childbearing years, 15-49)  Mortality ◦ Infant mortality rate (IMR) measures the annual number of deaths of infants under 1 year of age, compared to live births. ◦ Life expectancy measures the average number of years a newborn can expect to live at current mortality levels.

14. © 2011 Pearson Education, Inc. Notice that places with high TFRs tend to have high IMRs and that places with low TFRs have low IMRs. Figure 2-13 Figure 2-14

15. © 2011 Pearson Education, Inc. The Demographic Transition Population Pyramids Countries in different stages of the demographic transition Demographic Transition and world population growth

16. © 2011 Pearson Education, Inc. Why Is Population Increasing at Different Rates?  Demographic transition: The model Geographers use to discuss the growth and development countries go through. While countries grow and change in unique ways, all countries experience similar stages in development ◦ Four stages  Stage 1: Low growth  Agricultural revolution  Stage 2: High growth  Industrial Revolution  Stage 3: Moderate growth  Stage 4: Low growth  Zero population growth (ZPG)

17. © 2011 Pearson Education, Inc. Demographic Transition Figure 2-15

18. © 2011 Pearson Education, Inc. Why Is Population Increasing at Different Rates?  Population pyramids ◦ A bar graph showing a place’s age and sex composition ◦ Shape of the pyramid is determined mainly by the CBR ◦ Age distribution  Dependency ratio: people too young or old to work ◦ Sex distribution  Sex ratio: Number of males per hundred females

19. © 2011 Pearson Education, Inc. Population Pyramids Figure 2-19

20. © 2011 Pearson Education, Inc. Why Is Population Increasing at Different Rates?  Countries are in different stages of the demographic transition ◦ Three examples:  Cape Verde = High growth  Stage 2 since the 1950s  Chile = Moderate growth  Stage 3 since the 1960s  Denmark = Low growth  Stage 4 since the 1970s

21. © 2011 Pearson Education, Inc. Why Is Population Increasing at Different Rates?  Demographic transition & world population growth ◦ Most countries = stage 2 or stage 3 of the Demographic Transition  Stages 2 and 3 are characterized by significant population growth ◦ No country is in stage 1 of the demographic transition ◦ It is easier to cause a drop in the CDR than in the CBR

22. © 2011 Pearson Education, Inc. Malthus on Overpopulation Declining Birth Rates World Health Threats

23. © 2011 Pearson Education, Inc. Why Might Overpopulation be a Concern?  Malthus on overpopulation ◦ An Essay on the Principle of Population (1798): Population grows geometrically while food supply grows arithmetically: People are increasing faster than the food supply ◦ Criticism of Malthus includes the following:  Pessimistic viewpoint: the idea that the world’s resources is fixed rather than expanding (possiblism)  Failure to consider technological innovation  More people means more brains for developing good ideas  Marxist critique: Poverty, hunger, and other social welfare problems are a result of unjust social and economic institutions, not population growth

24. © 2011 Pearson Education, Inc. Malthus: Theory & Reality Figure 2-25

25. © 2011 Pearson Education, Inc. Why Might Overpopulation be a Concern?  Declining birth rates ◦ Reasons for declining birth rates  Reliance on economic development: wealthier communities tend to spend money on education and healthcare  Distribution of contraceptives  Women tend to attend school and stay in school longer resulting in more economic control, and more reproductive choices  Reducing birth rates with contraception Rapid diffusion of contraceptive methods

26. © 2011 Pearson Education, Inc. Family Planning Figure 2-30

27. © 2011 Pearson Education, Inc. Why Might Overpopulation be a Concern?  World health threats ◦ The epidemiologic transition focuses on distinctive causes of death in each stage of the demographic transition. Epidemiology: the study of distribution, incidence and control of diseases prevalent among populations at specific times that are not natural to the environment (Example: The 1918 Spanish Flu)  The epidemiologic transition  Stage 1: Characterized by pandemics brought about by infectious and parasitic diseases Malthus referred to these as “natural checks” for growth of the human population  The Black Plague or The Bubonic Plague: fleas and rats from trading ships during the late Middle Ages/early Renaissance

28. © 2011 Pearson Education, Inc. Why Might Overpopulation be a Concern?  The epidemiologic transition  Stage 2: Receding pandemics  During the Industrial Revolution improved Sanitation and new medical discoveries increases Life Expectancy  Cholera and Dr. John Snow  (The Ghost Map by Steve Johnson is a fabulous treatment of this event) Figure 2-31

29. © 2011 Pearson Education, Inc. Why Might Overpopulation be a Concern?  The epidemiologic transition  Stage 3: Degenerative and human created diseases  Decreased deaths from infectious diseases  Increased deaths from chronic disorders associated with aging  Higher instance of man made diseases: diabetes, cancer  Stage 4: Delayed degenerative diseases  Medical advances prolong life  Most significant: Heart disease and cancer  People still die from disease but due to medical advancements they can live longer or be cured all together  Increasing health and longevity is also a result of behavioral changes in human populations  Better diet and exercise  Reduced use of alcohol and tobacco products

30. © 2011 Pearson Education, Inc. Why Might Overpopulation be a Concern?  The epidemiologic transition  A possible stage 5: Reemergence of infectious diseases?  A set back in a long process of controlling infectious diseases  Three reasons why it might be happening:  Evolution: Infectious disease microbes have evolved and changed in response to environmental pressures by developing resistance to drugs and medicines (Ex. Malaria vs. disease resistant mosquitos)  Poverty: In LDCs high instances of poverty usher in the renewal of illnesses related to poverty and industrialization. (Ex. T.B.)  Improved travel: People traveling world wide and bringing new diseases home have seen a huge increase in the rapidity with which new diseases spread around the globe (Ex. Swine Flu)

31. © 2011 Pearson Education, Inc. The Most Lethal Infectious Disease: AIDS Figure 2-33

32. © 2011 Pearson Education, Inc. The End. Up next: Migration Figure 3-1