unit two: population
DESCRIPTION
UNIT TWO: POPULATION. Population Intro. Why important to study? More people on earth than at any other time in history (6.5 bill) World’s pop increased faster in second half of 20 th C than ever before - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/1.jpg)
UNIT TWO: POPULATION
![Page 2: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/2.jpg)
Population Intro
Why important to study?• More people on earth than at any other time in
history (6.5 bill)• World’s pop increased faster in second half of
20th C than ever before• Almost all global pop growth is occurring in
LDCs…poorest countries growing fastest…in some cases leads to famine and human suffering
• People are living longer – past 50 yrs global life expectancy has increased by 20 yrs
![Page 3: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/3.jpg)
DEMOGRAPHY
Demography: study of human pop Most demographers agree world pop
growth is slowing Project pop will plateau at @ 12 bill
some time in 21st C Historically pop growth has been
steady but certain events have checked it…..disease has been and continues to be biggest threat
![Page 4: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/4.jpg)
![Page 5: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/5.jpg)
2.1 Population Concentrations
Ecumene: portion of earth’s surface occupied by permanent human settlement• ¾ world pop live on 5% of earth’s
surface….Why? 2/3 of world pop lives in 4 regions
• 1.) EAST ASIA (E. China, Japan, Taiwan, Koreas China has 20 large urban areas, but 2/3 pop is rural China = world #1 ¾ Japan and Korea = urban
![Page 6: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/6.jpg)
4 Populous Regions - contd
• 2.) SOUTH ASIA (India, Pakistan, Bangladesh, Sri Lanka)
India = world #2 ¾ rural
• 3.) EUROPE – E and W…mostly urban• 4.) SE Asia (islands of Java, Sumatra,
Borneo, Papua New Guinea, Philippines, Vietnam, Thailand)
Indonesia = world #4 Mostly rural
![Page 7: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/7.jpg)
Top 10 Populous Nations
1. China 6. Pakistan 2. India 7. Russia 3. U.S.A. 8. Bangladesh 4. Indonesia 9. Nigeria 5. Brazil 10. Japan
• China and India expected to flip flop• U.S. will stay #3 b/c of immigration• LDCs taking top spots from MDCs
![Page 8: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/8.jpg)
Population Density
Arithmetic Density: total # of people divided by total area of land • Can be misleading b/c is an average• US = 78/sq mile, but Manhattan is
67,000/sq mile and Loving, TX .1/sq mile• Highest = Bangladesh, Japan,
Netherlands• Remember high pop (China) not
necessarily high pop density
![Page 9: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/9.jpg)
Pop Density cont’d
Physiological Density: ratio of people to a given unit of cultivable/arable land (suited for agriculture)• i.e. can you feed your population?• Can be high b/c of high pop density or
poor land• Ex: US 404/sq mile of arable land Egypt 9,073/sq mile of arable land
![Page 10: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/10.jpg)
![Page 11: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/11.jpg)
2.2 POPULATION GROWTH
Rule of Thumb….• Pop increases rapidly where many more
born than die• Slowly where births barely exceed
deaths• Decreases where deaths outnumber
births• Increases when people move in and
decreases when people move out
![Page 12: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/12.jpg)
Pop Change…measured 3 ways
1. Crude Birth Rate CBR: total # of births for every 1,000 alive
2. Total Fertility Rate TFR: average # of children a woman will have during child bearing yrs. Affected by: culture, religion, lifestyle, is child econ asset or drain, access to birth control, mother’s educ and career
![Page 13: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/13.jpg)
Pop Change – cont’d.
3. Natural Increase Rate NIR: • NIR = CBR – CDR• Calculates % by which pop grows each yr.• Ex: CBR = 20, CDR = 5, NIR = 1.5%• Excludes migration – only natural increase• A negative NIR means pop decreasing• World NIR peaked in 1963 at 2.2%• World NIR has declined in last 20 yrs.
![Page 14: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/14.jpg)
What determines a nation’s NIR? Factors to consider
Econ development Education Gender Empowerment – status and
power to women Health Care Culture (i.e. Catholics or Mormons) Public Policy (ex: China one child)
![Page 15: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/15.jpg)
Factors determining a nation’s NIR – cont’d.
Conclusions….countries w/ low econ development, low educ, low gender empowerment, but w/ lower infant mortality rates b/c of improved health care, cultural traditions favoring fertility, and no public policy limiting pop growth..have HIGHEST rates
![Page 16: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/16.jpg)
Where are these countries?
LDCs: sub Sahara Africa, parts of Middle East, parts of L. America
In MDCs pop growth is not natural but due to immigration
Irony – fastest growing places are least equip to deal w/ the growth
![Page 17: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/17.jpg)
Doubling Time
Doubling Time: # of yrs needed for a pop to double• Formula 70/NIR…ex: NIR is 2.6 % DT is 70/2.6
= 27 years• Pop growth is compounded/exponential (if rate
stays steady at 3% you’ll add more raw numbers each yr b/c base gets bigger)
• At 3% rate, DT is less than 25 yrs. Taking place in SS Africa, parts of ME, and parts of Central America
![Page 18: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/18.jpg)
MORTALITY
CDR
Infant Mortality Rate: annual # of deaths of infants under 1 yr compared w/ total # of births• In some parts of SS Africa is 10%
Life Expectancy: # or yrs a newborn can expect to live..75 in most MDCs, late 30s in some parts of Africa
![Page 19: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/19.jpg)
Population Growth Curves
S Curve – historical growth
J Curve – exponential growth (fixed percentage)
![Page 20: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/20.jpg)
Demographic Momentum
The tendency for pop growth to continue despite strict family planning b/c of young pop in child bearing yrs• Asia and LA 33% of pop under 15• Africa 40% of pop under 15• Ex: In 2002 both UK and S. Korea had
fertility rate of 1.6. But projections for 2025, older UK will decline by 2 mill and youthful SK will add 2 mill.
![Page 21: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/21.jpg)
![Page 22: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/22.jpg)
2.3 Demographic Transition Model
4 stage model shows similar process of pop change in all societies over time
Every country is at some stage The model is irreversible…you do not
go back
![Page 23: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/23.jpg)
STAGE ONE: LOW GROWTH
Very high CBR and CDR cancel each other out
Almost no long term natural increase Most of human history spent in stage
one No country is here today
![Page 24: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/24.jpg)
STAGE TWO: HIGH GROWTH
Rapidly declining CDR but CBR remains high and = very high NIR• @ 1750 – late 1800s nations in Ind Rev (Eur
and N. America) moved into stage 2. Improved agric and health care dropped CDR.
• First time in world history to have significant growth
• LDCs entered stage 2 @1950 when MDCs diffuse improved medical tech (vaccines) to LDCs.
• Most of Africa in stage 2 today
![Page 25: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/25.jpg)
STAGE THREE: MODERATE GROWTH
CBR rapidly declines and CDR continues to decline slowly. NIR begins to moderate
CBR drops b/c of social customs – access to birth control, infant mortality rate drops, women in work force, kids become econ drain
Eur and NA enter - first half of 20th C Asia and parts of LA moved here in recent
yrs
![Page 26: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/26.jpg)
STAGE FOUR: LOW GROWTH
Very low CBR and CDR produce almost no long-term natural increase and possibly a decrease
Zero pop growth: CBR and CDR =• TFR of 2.1 produces zero growth
Most Euro countries in stage 4 today Countries w/ negative NIR…Russia
and Japan (shrinking)
![Page 27: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/27.jpg)
Possible Stage Five?
In future if higher CDR than CBR you’ll have irreversible pop decline.
If a country stays in stage 5 without
migration it will eventually cease to exist
![Page 28: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/28.jpg)
Generalities of the Model
No one in stage 1; only a few have reached stage 4
Model has 2 big breaks w/ the past• First break: sudden drop in death rate
(stage 2) from technology and has taken place everywhere
• Second break: sudden drop in birth rate (stage 3) comes from changing social customs and has not taken place everywhere
![Page 29: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/29.jpg)
![Page 30: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/30.jpg)
2.4 Population Structure and Composition
Population pyramids…show age and gender groups. How do MDC’s and LDC’s differ?
• 1.) Sex Ratio: # of males per 100 females. In general slightly more males born, but women outlive men
Eur and NA 95 males: 100 females World wide 102 males: 100 females
![Page 31: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/31.jpg)
Pop Structure and Composition – cont’d.
2.) Age Distribution• Dependency Ratio: # of people too old or
young to work, compared to # of people in productive yrs.
% of pop under 15 = % over 65 divided by % in between 15-65 multiplied by 100
Tells you how many dependents for every 100 workers
Stage 2 countries: ratio is 1:1 (1 worker for every dependent) Dependents are young
Stage 4 countries ratio is 2:1 (2 workers for every dependent) Dependents are young and old
![Page 32: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/32.jpg)
Age Distribution – cont’d
• Graying of the pop in MDCs – more than ¼ of all govn’t expenditures in US, Canada, Japan, and W. Eur goes to Social Security, health care, and other programs for the elderly
• Baby Boomer Cohort in US (born 1946-1964)…what does this mean for you?
• Generation X = 1965-1980
![Page 33: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/33.jpg)
Population Structure and Composition – cont’d
Race and Ethnicity: Hispanics now largest minority in US (recently passed African Americans)• 11% of US pop is foreign born
50% of that from LA 50% of that from Mexico
![Page 34: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/34.jpg)
What do you see? Why?
![Page 35: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/35.jpg)
![Page 36: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/36.jpg)
Overpopulation and Sustainability
Should we worry @ overpopulation?• Thomas Malthus – 1798 wrote “Essay on
the Principle of Pop” and argued people need food to survive and have
natural desire to reproduce Food prod increases arithmetically and pop
increases geometrically/exponentially Predicted pop growth would eventually
outpace people’s ability to produce food leading to starvation and famine
![Page 37: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/37.jpg)
Malthus and his theory
![Page 38: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/38.jpg)
Neo Malthusians
Argue that 2 characteristics of recent pop growth make Malthus’ argument even more frightening• Esp high growth in LDCs• Pop growth outpacing econ dev in many LDCs
(i.e. income rises 20% but pop rises 30%, so some LDCs worse off than they were 30 yrs ago)
• Paul Erlich – most prominent neo-Malthusian. Wrote “Population Bomb” in 1968 – warned of mass starvation due to overpopulation
http://overpopulationisamyth.com/overpopulation-the-making-of-a-myth
![Page 39: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/39.jpg)
Critics of Malthus
Malthus did not account for ability of people to increase food prod dramatically w/ new technology (go to video 3)
Malthus did not foresee family planning and birth control and drop of CBR/NIR
Malthus did not recognize that famine is usually NOT related to a lack of food but to unequal dist of food – Marxist approach (Moderate approach)
http://overpopulationisamyth.com/overpopulation-the-making-of-a-myth
![Page 40: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/40.jpg)
Population and Sustainability
Carrying Capacity: # of people a given area can maintain…surpassed in densely populated places
Overpopulation implies a breach of an area’s carrying capacity. Also involves• Over consumption of resources• Inefficient allocation of goods• Unsustainable land use• MDC’s blame LDC’s – have too many babies• LDCs blame MDCs – consume disproportionate
share of world’s resources
![Page 41: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/41.jpg)
Control of Population
Pro-Natalist Policies – government policies to promote reproduction and bigger families• Ex. Tax breaks
Anti-Natalist – government and social policies that discourage reproduction to reduce pop growth rates• Tax breaks for sterilization• One-child policies – may lead to gender imbalance
![Page 42: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/42.jpg)
Control of Population
Improve local and state economies• Better school, more eco opportunities
Reduce CBR through the use of contraception • Family planning programs in LDCs• Why is this sometimes difficult?
![Page 43: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/43.jpg)
Epidemiological Transition Model
At times high CDR have lowered NIR Stage 1: Pestilence and Famine: i.e.
infectious diseases…ex: Black Plague 1350s kills ½ Eur pop
Stage 2: Receding Pandemics: improved sanitation, nutrition, medicine of Ind Rev decreases spread of infect diseases
![Page 44: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/44.jpg)
Epidemiological Transition Model Cont’d
Stage 3: Degenerative and Human Created Diseases• Fewer deaths from infectious diseases• Increase in chronic disease associated w/ aging
(heart disease and cancer) Stage 4: Delayed Degenerative Diseases –
degenerative diseases linger but life exp is extended trough medical advances (bypass, radiation, chemo, etc.)
![Page 45: UNIT TWO: POPULATION](https://reader035.vdocuments.site/reader035/viewer/2022062422/568136fd550346895d9e8b5f/html5/thumbnails/45.jpg)
Epidemiological Transition Model Cont’d
Possible Stage 5 – Reemergence of Infectious and Parasitic Diseases• Evolution of new strains of bacteria (TB,
polio, malaria)• Poverty – people cannot afford drug
treatment (TB)• Improved travel diffuses diseases faster
(AIDS)