Chapter 7Chapter 7

Sections 1-4Sections 1-4

Applying Population Applying Population Ecology: The Human Ecology: The Human

PopulationPopulation

Key ConceptsKey Concepts

Factors affecting population sizeFactors affecting population size

Human population problemsHuman population problems

Managing population problemsManaging population problems

Urban growthUrban growth

Resource and environmental problems in urban areasResource and environmental problems in urban areas

Transportation in urban areasTransportation in urban areas

Achieving sustainable citiesAchieving sustainable cities

Is the World Overpopulated?Is the World Overpopulated?

7.2 - 10.6 billion people by 20507.2 - 10.6 billion people by 2050

Limited resourcesLimited resources

Environmental impacts Environmental impacts (I=PAT)(I=PAT)

Some say no- Some say no- Longer lifespansLonger lifespans

Economic growth- Economic growth- stimulated by pop. increasestimulated by pop. increase

Religion and population growthReligion and population growth

Freedom and population growthFreedom and population growth

PovertyPoverty- - 20% people without basic necessities20% people without basic necessities

Ecological footprintEcological footprint

Fig. 7-1, p. 128

Is the World Overpopulated?Is the World Overpopulated?

Fig. 7-1, p. 128

Click for Current US and World Population

http://www.census.gov/main/www/popclock.html

Factors Affecting Human Factors Affecting Human Population SizePopulation Size

Population change equationPopulation change equation

Population change = (Births +Immigration) – (Deaths + Emigration)Population change = (Births +Immigration) – (Deaths + Emigration)

Crude birth rateCrude birth rate = = # live births per 1,000 people per year# live births per 1,000 people per year

Crude death rateCrude death rate = = # deaths per 1,000 people per year# deaths per 1,000 people per year

Global population growthGlobal population growth = = 1.2% = 214,000 people per day (97% in 1.2% = 214,000 people per day (97% in developing countries)developing countries)

Rule of 70: Rule of 70: 70/ percentage growth rate = doubling time in years70/ percentage growth rate = doubling time in years

Doubling time: Doubling time: 70/1.2 = 58 years70/1.2 = 58 years

Fig. 7-2a, p. 130

Average crude birth rate Average crude death rate

World

All developedcountries

All developingcountries

Developingcountries

(w/o China)

21

9

11

10

24

8

27

9

Average Crude Birth and Death Rates Average Crude Birth and Death Rates

World’s birth rate = 2.1%

World’s death rate = 0.9%

World’s pop. Growth rate = 1.2%

Crude Growth Rate ÷ 10 = % Growth Rate

Average crude birth rate Average crude death rate

Africa

LatinAmerica

Asia

Oceania

UnitedStates

NorthAmerica

Europe

3814

22

6

20

7

18

7

14

8

148

10

12

Fig. 7-2b, p. 130

Average Crude Birth and Death Rates Average Crude Birth and Death Rates

AnimationAnimation

Current and projected population sizes by region.

How Did the Human Population How Did the Human Population Increase So Rapidly?Increase So Rapidly?

1.1. Human intelligence and adaptationHuman intelligence and adaptation- - enabled enabled expansion to diverse habitats & new climate zonesexpansion to diverse habitats & new climate zones

2.2. Agriculture - Agriculture - feeds more people per unit areafeeds more people per unit area

3.3. Medical technologies and sanitationMedical technologies and sanitation- - controls controls infectious diseaseinfectious disease

Describing Population ChangesDescribing Population Changes

Replacement-level fertilityReplacement-level fertility= = # children a couple must bear to replace themselves (approx 2.1 - 2.4)# children a couple must bear to replace themselves (approx 2.1 - 2.4)

Total fertility rate (TFR)Total fertility rate (TFR)= = average # children woman has in her reproductive years average # children woman has in her reproductive years (2005 TFR = 2.7) (TFR in MDCs = 1.6 : LDCs = 3.0)(2005 TFR = 2.7) (TFR in MDCs = 1.6 : LDCs = 3.0)

Projecting global populationsProjecting global populations: : 2050 projected pop. = 7.2-10.6 billion2050 projected pop. = 7.2-10.6 billionMost growth (97%) expected in developing countriesMost growth (97%) expected in developing countries

US fertility ratesUS fertility rates- - see figure 7-4, p. 131see figure 7-4, p. 131

World Population Projections World Population Projections

Fig. 7-3, p. 131

Fig. 7-4, p. 131

US Fertility Rates (1917-2005) US Fertility Rates (1917-2005)

47 years

77 years

8%

81%

15%

83%

10%

98%

2%

99%

10%

52%

$15

$3

1.2

5.8

1900

2000

Life expectancy

Married women workingoutside the home

High school graduates

Homes with flush toilets

Homes with electricity

Living in suburbs

Hourly manufacturing jobwage (adjusted for inflation)

Homocides per100,000 people Fig. 7-5, p. 132

Major Changes in US Society Major Changes in US Society (1900-2000) (1900-2000)

Factors Affecting Birth Rates Factors Affecting Birth Rates and Fertility Rates ***and Fertility Rates ***

Child labor-Child labor- very important in developing countriesvery important in developing countries

Cost of raising and educating childrenCost of raising and educating children - more expensive in developed countries- more expensive in developed countries

Availability of pension systems Availability of pension systems - pensions reduce need for children to support in old age- pensions reduce need for children to support in old age

Urbanization-Urbanization- better access to family planning services in citiesbetter access to family planning services in cities

Education and employment of womenEducation and employment of women - - TFR drops with increasing education & employment opportunitiesTFR drops with increasing education & employment opportunities

Infant mortality rateInfant mortality rate - - Directly proportional to TFRDirectly proportional to TFR

Average age of marriageAverage age of marriage- - Fewer children when marriage age ≥ 25 yearsFewer children when marriage age ≥ 25 years

AbortionAbortion- - 46 million abortions yearly (20 million illegal)46 million abortions yearly (20 million illegal)

Availability of birth controlAvailability of birth control

Culture, religious values, and traditionsCulture, religious values, and traditions

Extremely Effective

Highly Effective

Total abstinence

Sterilization

Vaginal ring

IUD with slow-releasehormones

IUD plus spermicide

Vaginal pouch(“female condom”)

IUD

Condom (good brand)plus spermicide

Oral contraceptive

100%

99.6%

98-99%

98%

98%

97%

95%

95%

93%

Fig. 7-6a, p. 133

Very Effective Birth Control MethodsVery Effective Birth Control Methods

Effective

Cervical cap

Condom (good brand)

Diaphragm plusspermicide

Rhythm method (Billings,Sympto-Thermal)

Vaginal sponge impreg-nated with spermicide

Spermicide (foam)

89%

86%

84%

84%

83%

82%

Fig. 7-6b, p. 133

Mostly Effective Birth Control Mostly Effective Birth Control MethodsMethods

Moderately Effective

Unreliable

Spermicide (creams,jellies, suppositories)

Withdrawal

Rhythm method (dailytemperature readings)

Condom (cheap brand)

Douche

Chance (no method)

75%

74%

74%

70%

40%

10%

Fig. 7-6c, p. 133

Least Effective Birth Control Least Effective Birth Control MethodsMethods

Factors Affecting Death RatesFactors Affecting Death Rates

Life expectancyLife expectancy: : global averageglobal average years = 67 years = 67

Infant mortality rate Infant mortality rate == # of babies out of every 1,000 who die before 1st birthday# of babies out of every 1,000 who die before 1st birthday** Best single measure of a society’s quality of life (reflects nutrition, health care)** Best single measure of a society’s quality of life (reflects nutrition, health care)46 countries have lower infant mortality rates than USA46 countries have lower infant mortality rates than USA

Improvements: Food, medicine, nutrition, Improvements: Food, medicine, nutrition, medicine, sanitation, hygiene, water medicine, sanitation, hygiene, water supplysupply

Immigration into the USImmigration into the US 41% of annual population growth41% of annual population growth

Source of immigrants into the USSource of immigrants into the USPre 1960: Mostly EuropePre 1960: Mostly EuropePost 1960: Latin America (53%), Asia (25%), Europe (14%)Post 1960: Latin America (53%), Asia (25%), Europe (14%)

Arguments to reduce immigrationArguments to reduce immigration : : 58% support58% support

• Allow population stabilize • Allow population stabilize • Reduce environmental impact• Reduce environmental impact

Arguments for immigrationArguments for immigration• “Give me your hungry, your tired your poor…’• “Give me your hungry, your tired your poor…’• Tax revenues $$$• Tax revenues $$$• immigrants occupy menial, low-paying jobs• immigrants occupy menial, low-paying jobs• After 2020 workers will be needed as Boomers retire• After 2020 workers will be needed as Boomers retire

CNN Video- “CNN Video- “Immigration”Immigration”

QuickTime™ and aSorenson Video decompressorare needed to see this picture.

Fig. 7-8, p. 135

Expanding RapidlyGuatemala

NigeriaSaudi Arabia

Male Female

Prereproductive ages 0-14 Reproductive ages 15-44 Postreproductive ages 45-85+

Population Age Structures Population Age Structures

Male Female Male Female Male Female

Expanding SlowlyUnited States

AustraliaCanada

StableSpain

AustriaGreece

DecliningGermanyBulgaria

Italy

In 2005, 29% of people on planet were younger than 15 years old

1.5 - 3% 0.3 - 1.4% 0 - 0.2% Negative growth

AnimationAnimation

Examples of age structure interaction

Fig. 7-10, p. 136

Tracking the US Baby Boom Tracking the US Baby Boom Generation Generation

AnimationAnimation

U.S. age structure interaction.

Effects of Population DeclineEffects of Population Decline 40 nations have stable or declining populations40 nations have stable or declining populations

UN predicts that pop of most develop countries will UN predicts that pop of most develop countries will stabilize by 2050 (not USA)stabilize by 2050 (not USA)

Rapid declines can create severe social and economic Rapid declines can create severe social and economic problemsproblems

Labor and social security problemsLabor and social security problems

Social and economic impacts of AIDSSocial and economic impacts of AIDS

Solutions: Influencing Solutions: Influencing Population SizePopulation Size

***Demographic transition***Demographic transition

Family planningFamily planning

Improve health careImprove health care

Empowering women- Empowering women- worldwide, women account for 66% of hours worked, but receive 10% of world’s worldwide, women account for 66% of hours worked, but receive 10% of world’s income. See stats of p.138income. See stats of p.138

Developing national population policiesDeveloping national population policies

Improve education, especially for womenImprove education, especially for women

Increase involvement of men in parentingIncrease involvement of men in parenting

Reduce povertyReduce poverty

Reduce unsustainable consumptionReduce unsustainable consumption

Fig. 7-11, p. 137

Stage 1Preindustrial

Stage 2Transitional

Stage 3Industrial

Stage 4Postindustrial

Low Increasing Very high Decreasing Low Zero Negative

Birth rate

Total population

Death rate

Growth rate over time

Demographic Transition Demographic Transition

Low

High

Rel

ati

ve

po

pu

lati

on

siz

e

Bir

th r

ate

an

d d

eath

rat

e(n

um

ber

per

1,0

00 p

er

yea

r)

0

10

20

30

40

50

60

70

80

Animation- Animation- Demographic transition model

Case Study: Hindrances to Case Study: Hindrances to Family Planning Programs in Family Planning Programs in

IndiaIndia

Poor planning of family planning programsPoor planning of family planning programs

Bureaucratic inefficiencyBureaucratic inefficiency

Low status of womenLow status of women

Extreme povertyExtreme poverty

Lack of administrative and financial supportLack of administrative and financial support

Case Study: Family Planning in Case Study: Family Planning in ChinaChina

Economic incentivesEconomic incentives- - extra food, larger pensions, better housing,extra food, larger pensions, better housing, $$ $$

Free medical care for participantsFree medical care for participants

Preferential treatment for participantsPreferential treatment for participants- free school tuition- free school tuition

Very coercive and intrusiveVery coercive and intrusive- - free sterilization, contraception, free sterilization, contraception,

Human rights violations- Human rights violations- gender imbalance, abortions, infanticidegender imbalance, abortions, infanticide

China’s Pop could peak in 2040, then declineChina’s Pop could peak in 2040, then decline

Fig. 7-12, p. 139

Percentageof world

population

Population

Population (2025)(estimated)

Illiteracy (%of adults)

Population under age 15(%)

Population growth rate (%)

Total fertility rate

Infant mortality rate

Life expectancy

GDP PPP per capita

17%20%

1.1 billion1.3 billion

1.4 billion1.63 billion

47%17%

36%22%

1.6%0.6%

3.0 children per woman (down from 5.3 in 1970)1.7 children per woman (down from 5.7 in 1972)

6427

62 years 71 years

$2,880 $4,980

Demographic Data on India and Demographic Data on India and China China

8147

Percent living below $2 per day