1. UNIT 2 REVIEW POPULATION & MIGRATION

2. POPULATION CONCENTRATIONS

3. DENSITY Arithmetic- total number of objects in a given area (population /land area) Physiological – the number of people supported by a unit area of arable land Agricultural density- the ratio of the number of farmers to arable land What can these numbers tell us, why are they important to geographers?

4. COMPONENTS OF POPULATION GROWTH Crude Birth Rate (CBR)-Total number of live births in a year for every 1,000 people alive in the society Crude Death Rate (CDR)-Total number of deaths in a year per every 1,000 people in a society Natural Increase Rate (NIR)-percentage by which the population grows in a year (excludes migration) Current World NIR is 1.2% (doubles every 82 years)

5. TOTAL FERTILITY RATE (TFR) The average number of children a woman will have throughout her childbearing years (15-49) World Average- 2.5 Exceeds 5 in Africa 2 or less in all European Countries Why is this important?

6. DEPENDENCY RATIO The number of people to young or too old to work compared to the people in their productive years What is the impact of a very young population on a society? Very old?

7. SEX RATIO Number of males per 100 females in the population Why is this an important statistic? http://www.youtube.com/watch?v=ISme5-9orR0

8. DEMOGRAPHIC TRANSITION MODEL

9. 1. EPIDEMIOLOGICAL TRANSITION Concept Focuses on changes over time in the causes of mortality affecting certain populations: Health conditions. Disease patterns. Result in a decline in death rates and an increase of life expectancy. The society goes through a transition from communicative diseases to degenerative diseases.

10. 1. EPIDEMIOLOGICAL TRANSITION Time Share of mortality Communicative diseases Degenerative diseases Age of communicative diseases Age of receding pandemics Age of degenerative and man-made diseases High Fertility High Mortality High Fertility Decreasing Mortality Low Fertility Low Mortality LI=70 years LI=50 years LI=30 years

11. Stage 1: “ Pre-Industrial ” High birth rates and high death rates (both about 40) Population growth very slow Agrarian society High rates of communicable diseases Pop. increases in good growing years; declines in bad years (famine, diseases) No country or world region still in Stage One

12. Stage 2: “ Early Industrial ” High birth rates (over 30) but death rates decline (to about 20) RNIs increase sharply (pop. explosion); growth rate increases thruout Stage Two Growth not from increase in births, but from decline in deaths MDCs = starts early 1800s LDCs = starts after 1950s

13. THE EPIDEMIOLOGICAL TRANSITION Agricultural technology Improvements in food supply: higher yields as agricultural practices improved in “Second Agricultural Revolution” (18 th Century) In Europe, food quality improved as new foods introduced from Americas Medical technology Better medical understanding (causes of diseases; how they spread) Public sanitation technology Improved water supply (safe drinking water) Better sewage treatment, food handling, and personal hygiene Improvements in public health especially reduced childhood mortality

14. Stage 3: “ Later Industrial ” Birth rates decline sharply (to about 15) Death rates decline a bit more (to about 10 or less) Note growth still occurs, but at a reduced and declining rate MDCs = starts in late 1800s LDCs = starts after 1980s* * Or hasn ’ t started yet

15. Measles Mortality, US, since 1900 TB Mortality, US, since 1900 Stage Three: Further improvements in medicine lower death rates more; raise life expectancies

16. THE FERTILITY TRANSITION Societies become more urban less rural Declining childhood death in rural areas (need fewer kids) Increasing urbanization changes traditional values regarding having children City living raises cost of having dependents Women become more influential in childbearing decisions Increasing female literacy changes valued placed on motherhood as sole measure of women’s status Women enter the work force: life extends beyond family, changes attitude toward child bearing Improved contraceptive technology, access to/availability of birth control But contraceptives were not widely available in 19 th century and not a significant cause of fertility decline in Europe… Fertility decline relates more to changing values than to availability of any specific technology What is the number one method for reducing the fertility rate?

17. Stage 4: “ Post-Industrial ” Birth rates and death rates both low (about 10) Population growth very low or zero MDCs = starts after 1970s LDCs = hasn ’ t started yet Stage 5 (?): Hypothesized (not in Classic DTM) Much of Europe now or soon in population decline as birth rates drop far below replacement level

18. POPULATION STRUCTURE The population pyramid displays the age and sex structure of a country or given area Usually, but not always, in % to make for easier comparisons between countries FEMALES To the right MALES To the left Population in Five Year Age bands OLD DEPENDANTS ECONOMICALLY ACTIVE YOUNG DEPENDANTS

19. What Population Pyramids Show Us KEY slope of pyramid indicate the death rate width of the base is related to birth rate/fertility rate proportions of men and women can suggest male or female migrations height of graph can indicate life expectancy (ignore the very thin end of the wedge as occurs on graph B as these people are a definite minority) "kinks" indicate dramatic reductions in birth rate or increases in death rate in the past area of graph indicates total population - compare areas of different population age groups or different sex on one graph The overall shape of the population pyramid can indicate whether it is an Economically More Developed Country or Economically Less Developed Country Economically More Developed Country Economically Less Developed Country

20. Population Pyramids related to the Demographic Transition Model Stage 1 Stage 2Stage 3Stage 4 Both birth rates and Death rates are High, so population growth rates are slow but population Is usually restored Due to high birth Rate. Short life Expectancy EXAMPLES: none today - Afghanistan, Ivory Coast (30 years ago)There are no Stage 1 countries today Population starts to grow at an exponential rate due to fall in Crude Death Rate. More living In middle age. Life expectancy rises Infant mortality rate falls. EXAMPLES: DR Congo, Yemen, Afghanistan (today) Population continues to grow but at slower rate. Low C Death Rate. Dramatically declining Crude Birth Rate. EXAMPLES: India, Brazil (late 3) – Most of world is in 3 IMPLICATIONS Low Crude Birth Rate and Crude Death Rate Higher dependency ratio and longer life expectancy Crude Death Rate does Rise slightly because of The ageing population EXAMPLES: China, United States, Canada, Australia There is some merit in including or considering a Stage 5 today with a declining population- Europe - Japan

21. PRACTICE WITH REAL PYRAMIDS-WHAT STAGE OF DTM? 3 2 4 5

22. MALTHUS ’ THEORY OF POPULATION GROWTH In 1798 Thomas Malthus published his views on the effect of population on food supply. His theory has two basic principles: 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.

23. ESTHER BOSERUP ’ S THEORY OF POPULATION GROWTH In contrast to Malthus, instead of too many mouths to feed, Boserup emphasized 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.

24. WHAT IS MIGRATION? Movement Cyclic movement : Movement away from home for a short period Commuting Seasonal movement Nomadism Periodic movement : Movement away from home for a longer period. Migrant labor Transhumance Military service Migration : A change in residence intended to be permanent

25. International migration: Movement across country borders (implying a degree of permanence)

26. Internal migration: Movement within a single country’s borders (implying a degree of permanence)

27. WHY DO PEOPLE MIGRATE? Forced migration: Movers have no choice but to relocate

28. KINDS OF VOLUNTARY MIGRATION Step migration : When a migrant follows a series of stages, or steps, toward a final destination. Intervening opportunity : At one of the steps along the path, pull factors encourage the migrant to settle there Chain migration : Further migration to a place where friends or relatives have already settled

29. VOLUNTARY MIGRATION Migrants weigh push and pull factors to decide Whether to move Where to go Distance decay : Many migrants settle closer to their old home than they originally contemplate

30. PUSH VS PULL FACTORS Push Factors: Elements that induce or encourage a person to migrate or move out of their present location. Pull Factors: Elements that induce or encourage a person to migrate or move into a new location. Either can be economic, environmental, cultural or political. Question: Describe a push factor that explains why people leave Mexico. Describe a pull factor that explains why people are pulled to US.

31. RAVENSTEIN’S LAWS 1.Every migration flow generates a return or countermigration. 2.The majority of migrations move a short distance. 3.Migrants who move longer distances tend to choose big-city destinations. 4.Urban residents are less migratory than inhabitants of rural areas. 5.Families are less likely to make international moves than young adults.

32. GRAVITY MODEL: READ AND TAKE NOTES KUBY CHAPTER 4

33. GLOBAL MIGRATION PATTERNS Fig. 3-2: The major flows of migration are from less developed to more developed countries.

34. NET MIGRATION (PER POPULATION) Fig. 3-3: Net migration per 1000 population. The U.S. has the largest number of immigrants, but other developed countries also have relatively large numbers.

35. MIGRATION TO U.S., BY REGION OF ORIGIN Fig. 3-4: Most migrants to the U.S were from Europe until the 1960s. Since then, Latin America and Asia have become the main sources of immigrants.

36. GUEST WORKERS Migrants allowed into a country to fill a labor need, assuming the workers will go “home” once the labor need subsides  Have short term work visas  Send remittances to home country

37. REFUGEES People who flee across an international boundary because of a well-founded fear of being persecuted for reasons of race, religion, nationality, membership of a particular social group, or political opinion

38. ZELINSKY AND MIGRATION TRANSITION Post-Transitional: “advanced societies” – ↑ circulation for leisure (summer homes etc.) – Rural → urban transition finished – International Labor Migration from LDCs to MDCs – High rate of International urban → urban (job relocation) Future “post industrial” (Is the Future here?) – communications technology may reduce need to migrate – “Rebound” of Urban → Rural migration

39. BY STAGE Stage 1 = rural, traditional societies focused on subsistence: mobility is limited and dictated by local custom (trade, religion, war) Stage 2 & 3 = increased population pressure leads to increased migration (increased technology leads to increased mobility) 1) rural to urban (economic opportunity) 2) new agricultural areas (European colonialism) Stage 4 = very mobile 1) rural to urban slows 2) mobility between urban areas (move to suburbs) 3) for employment opportunities (job change)

40. REGIONAL IMPACTS Europe = keeps economy going, rapidly changing cultures The US & Canada = Stay in stage 4, helps economy… Africa = net out-migration and Brain Drain Asia = More out migration, some Brain Drain* Australia- growing economy, net in migration similar to Canada and US