Fall 2019 APES Chapter 8

Lecture Outlines

Chapter 8

Human Population

This lecture will help you understand:



Human population growth



Different viewpoints on this growth



Population, affluence, and technology’s effects



Demography



Demographic transition



Factors affecting population growth



The HIV/AIDS epidemic

Central Case Study: China’s One-Child Policy

 In 1970, China’s 790 million people were exhausting their resources and faced starvation if growth continued

 The government instituted a one-child policy

 The growth rate plummeted

 The policy is now less strict

 The successful program has had unintended consequences

 Killing of female infants and an imbalance in male to female ratios

Our World at Seven Billion



Populations continue to rise in most countries,

particularly in poverty-stricken developing nations



Growth in poorer nations leads to stresses on

society, the environment, and people’s well-being



China’s stringent policies have greatly slowed

growth there, but other countries may wish to slow

their growth without the measures used by China

 India’s growth continues and if not changed will surpass China’s population

The Population Explosion



The current world population is 7.732 Billion as of

September 25, 2019.



Each time your heart beats, three more people are

added to the world.



Each time a person dies 2.8 babies are born.

The human population is growing rapidly



Our population grows by over 70 million each year



It took until 1800 to reach 1 billion



In 1930 (130 years later) we reached 2 billion



We added the most recent billion in 12 years



Growth rates vary from country to country

 Some countries are over 3%, while other country’s populations are shrinking



The current world growth rate is 1.2%

Is population growth a problem?



Better technology, sanitation, medication, and

increased food supply have increased growth

 Death rates drop, but not birth rates

 Infant mortality rate  the death rate in children; has dropped dramatically



Population growth was seen as good

 Support for elderly, a larger labor pool



Thomas Malthus’s An Essay on the Principles of

Population

(1798)

 Humans will outstrip food supplies

Is population growth a problem?

 Neo-Malthusians: population growth will increase faster than food production; cause famine and conflict

 Paul Ehrlich’s Population Bomb (1968) predicted that civilization would end by the end of the 20th century

 Intensified food production fed more people

 Cornucopians argue that we will continue to find new resources and technology to support people

 Environmental scientists argue that there are finite resources

 Land is limited, extinct species are gone forever

 Quality of life will suffer with unchecked growth

Some national governments now fear falling

populations



Policymakers believe population growth increases

economic, political, and military strength



But growth is correlated with poverty, not wealth

 Strong, rich nations have low growth rates

 Weak, poor nations have high growth rates



Some nations offer incentives for more children

 Elderly need social services



66% of European governments think their birth rate

is too low

Population is one of several factors that affect

the environment



The

IPAT model

:

I



P

×

A

×

T

×

S



Total impact (

I

) on the environment results from:

 Population (P)  individuals need space and resources

 Affluence (A)  greater per capita resource use

 Technology (T)  increased exploitation of resources, but also pollution controls and renewable energy

 Sensitivity (S)  how sensitive an area is to human pressure (e.g., arid land vs. rainforest)

Population is one of several factors that affect

the environment



Impact equates to pollution or resource consumption

 Humans use 25% of Earth’s net primary production



Technology has increased efficiency and reduced

our strain on resources, resulting in further

population growth

 For example, increased agricultural production



Modern China’s increasing affluence is causing:

 Increased resource consumption

Modeling Population Growth—

Modeling Population Growth—

Human Population Growth and Regulation 1

Modeling Population Growth

Modeling Population Growth

Modeling Population Growth

Demography



Demography



the application of population

ecology to the study of change in human populations

 All population principles apply to humans

 Environmental factors limit population growth



There is a carrying capacity for all species, including

humans

 Humans raise the environment’s carrying capacity through technology



How many humans can the world sustain?

 1 billion to 33 billion: prosperity to abject poverty

Demography is the study of human population



Demographers

study:

 Population size

 Density and distribution

 Age structure

 Sex ratio

 Birth, death, immigration, and emigration rates



Population size

 Current world population is just over 7 billion

D. Changing Fertility Rates and the Demographic Transition

1. The gradual shift from the primitive to the modern condition that is correlated with development is called demographic transition.

2. Crude Birth Rate (CBR) is the number of births per 1000 individuals per year. Crude Death Rate (CDR) is the number of deaths per 1000

individuals per year. The term crude is used because there is no consideration for age or gender.

3. Subtracting the CDR from the CBR gives the increase or decrease per 1000 per year. Dividing this result by 10 then puts it in terms of per 100 or percent. We will call this number the percent

increase or decrease per year.

Calculating Fertility Rates and Doubling Times

(CBR - CDR)/10 = Rate of Increase or decrease

in population per 100 per year or growth

percentage rate

5. The Demographic transition has four phases.

a) Phase I is the primitive stability, with high

CBR’s and CDR’s.

b) Phase II is marked by a declining CDR that

results from improved infant mortality rates. There is a large population growth due to the fact that CBR’s do not go down. This phase is also know as Epidemiologic transition.

c) Phase III is a phase of declining CBR’s

resulting from a declining fertility rate. This phase is also known as Fertility transition.

d) Phase IV is reached, where modern stability

Phases of Demographic Transition



Phase I: primitive stability (CBR = CDR)



Phase II: declining CDR, CBR remains high

accelerating population growth



Phase III: declining fertility rate, but significant

population growth continues

Demographic Transition Comparisons (Figure

5-17)



Phase IV: developed countries

Population density and distribution



Population size alone does not tell whole story

 People are not distributed equally over the planet (clumped distribution)



Highest density: temperate, subtropical, tropical

biomes and close to water

 Cities are local high-density areas



Lowest density: away from water, extreme

environments

Age structure



Age structure describes the relative numbers in each

age class within a population



Age structure diagrams (population pyramids) show

age structure



Wide base denotes many young

 High reproduction, rapid population growth



Even age distribution: remains stable as births keep

pace with deaths

Age structure



Many populations are getting older



Median global age today is 28, but it will be 38 by

2050

 The elderly will need care and financial assistance

 Taxes will increase for Social Security and Medicare

Age structure



China’s age structure is changing

 In 1970, the median age was 20; by 2050 it will be 45



By 2050, over 300 million will be over 65

Sex ratios

 Unequal sex ratios can impact population growth

 Human sex ratios at birth slightly favor males

 For every 100 females born, 106 males are born

 In China, 120 boys were reported for 100 girls

 Culture values males over females

 The government’s one-child policy

 Females have been selectively aborted

 The undesirable social consequences?

 Many single Chinese men

Population change results from birth, death,

immigration, and emigration



Whether a population grows, shrinks, or remains

stable depends on rates of birth, death, and

migration

 Birth and immigration add individuals

 Death and emigration remove individuals



Technological advances caused decreased deaths

Population change results from birth, death,

immigration, and emigration



Immigration/emigration have become more

important

 War, civil strife, and environmental degradation cause people to flee their homes

 Each year, 25 million refugees escape poor environmental conditions



This movement causes environmental problems

 No incentives to conserve resources

Total fertility rate influences population growth



Total fertility rate

(TFR)



the average number of

children born to each female



Replacement fertility



the TFR that keeps the size

of a population stable (about 2.1)



TFR has been decreasing in many nations due to:

 Industrialization

 Improved women’s rights

 Quality health care



In Europe as a whole, TFR is now 1.6

Many nations are experiencing the

demographic transition



In countries with good sanitation, health care, and

food, people live longer



Life expectancy



average number of years that an

individual is likely to continue to live

 Has increased with reduced rates of infant mortality



Demographic transition



a model of economic

and cultural change

 Explains the declining death and birth rates in industrializing nations

Many nations are experiencing the

demographic transition



Pre-industrial stage



in pre-industrial societies,

both birth and death rates are high

 High birth rate to compensate for high infant mortality

 Population growth is slow



Transitional stage



declining death rates due to

increased food production and medical care

 Birth rates remain high since people are not used to the low infant mortality rates

Modeling Population Growth—

Human Population Growth and Regulation 4

Many nations are experiencing the

demographic transition



Industrial stage



birth rates fall as jobs provide

opportunities for women outside the home and

children are not needed in the workforce

 Difference between birth and death rates shrinks

 Population growth slows



Post-industrial stage



birth and death rates are

low and stable

Demographic information

1. HDC, High income type country, like Canada, Western Europe, and the United States.

2. MDC, Middle income countries, like Latin America, parts of Asia, and parts of Africa. 3. LDC, Low income countries, like China,

central Africa, central Asia.

4. The disparity in distribution of wealth among countries of the world is large. HDC’s have 18.8% of the population and 80% of the world’s

wealth. The MDC’s and LDC’s combined have 81.2% of the world’s population and only 20%

Average Number of Children, Grandchildren,

and Great Grandchildren



America



West Germany



Africa



14



5

Major Economic Divisions of the World

Is the demographic transition a universal

process?



It has occurred in Europe, the U.S., Canada, Japan,

and other nations over the past 200–300 years



But it may or may not apply to developing nations



The transition could fail in cultures that:

 Place greater value on childbirth

 Grant women fewer freedoms

For people to attain the material standard of living of North Americans, we would need the natural

Population and Society



Many factors affect fertility in a given society:

 Access to family planning

 Rates of infant mortality

 Levels of women’s rights

 Level of affluence

 Importance of child labor

Family planning is a key approach for

controlling growth



Family planning



efforts to control the number and

spacing of children; the greatest single factor

slowing population growth

 Clinics offer advice, information, and contraceptives



Birth control



effort to control the number of

children born by reducing the frequency of

pregnancy

 Contraception  deliberate prevention of pregnancy through a variety of methods

Family planning is a key approach for

controlling growth



Low use of family planning may have different

causes

 Rural areas may have limited availability

 Religious doctrines or cultural influences may reject family planning



Family planning gives women control over their

reproductive window



time frame where a woman

can become pregnant

 Potential to produce 25 children during the window

Family-planning programs are working around

the world



Funding and policies that encourage family planning

lower population growth rates in all nations,

regardless of level of industrialization



Thailand’s educational-based approach to family

planning reduced its growth rate from 2.3% to 0.5%

 Brazil, Mexico, Iran, Cuba, and other developing countries have active programs

 These entail setting targets and providing incentives, education, contraception, and reproductive health

Empowering women reduces fertility rates



Where women are freer to decide whether and when

to have children, fertility rates fall, and children are

better cared for, healthier, and better educated.



Fertility rates drop most noticeably when women

gain access to contraceptives and family-planning

programs



As women receive educational opportunities, fertility

rates decline

 Two-thirds of the world’s illiterate are women

Increasing affluence lowers fertility



Poorer societies have higher population growth rates

 Consistent with the demographic transition theory

 High fertility to ensure some children would survive and be able to contribute to farm labor



More affluent societies can provide:

 Better medical care, reducing infant mortality

 Education for children (removing them from the workforce and making them an economic liability)

 Social security for the elderly

Increasing affluence lowers fertility



Poverty exacerbates population growth; population

growth exacerbates poverty



In 1960, 70% of all people lived in developing

nations

 As of 2010, 82% live in these nations

 99% of the next billion will be born in these nations



Population growth in poor nations increases

environmental degradation

 Farming degrades soil in arid areas (Africa, China)

Expanding wealth can increase the

environmental impact per person



Affluent societies have enormous resource

consumption and waste production

 People use resources from other areas, as well as from their own

 Ecological footprints are huge



People in affluent societies have larger ecological

footprints

 One American has as much environmental impact as 3.8 Chinese or 8 Indians or 14 Afghans

Expanding wealth can increase the

environmental impact per person



Biocapacity



the amount of biologically productive

land and sea available to us

 Ecological deficit  ecological footprint  biocapacity

 Ecological reserve  ecological footprint  biocapacity



We are running a global ecological deficit

 Humanity’s global ecological footprint exceeds biocapacity by 50%

HIV/AIDS is exerting major impacts on African

populations



The AIDS epidemic is having the greatest impact

since the Black Death in the 14th century



Of 34 million infected, two-thirds live in sub-Saharan

Africa; 3800 die/day

 Low rates of contraceptive use spread the disease

 Infant mortality is 14 times that of the developed world

 Life expectancy has dropped from 60 years in the 1990s to 40–50 years today

Demographic change has social and economic

repercussions



AIDS undermines the ability of poor nations to

develop

 Removes productive members of society

 Cost of medical treatment is a huge burden

Demographic change has social and economic

repercussions



Demographic fatigue



occurs when governments

face overwhelming challenges related to population

growth

 With the added stress of HIV/AIDS, governments are stretched beyond their capabilities

 Problems grow worse and citizens lose faith

Population goals support sustainable

development



1994 UN conference on population and development

 Rejected top-down, command-and-control approaches that pushed contraceptives and preset targets

 Urged education and health care

 Urged addressing social needs (like poverty, sexism) from the bottom up



To generate a high quality of life for all people,

developing nations must slow population growth

Factors Influencing Family Size

• Old age security

• Infant and childhood mortality rates

• Children: an economic asset or liability

• Importance of education

• Status of women

I Reassessing the Demographic Transition A. Factors Influencing Family Size

1. Security in one’s old age: In many LDC’s the only way that the old are taken care of is by their

families. In the HDC’s we have nursing homes and Social Security. This is one of the reasons they have many children, so that someone is left

2. Infant and Childhood Mortality: The common and often personal experience of children dying

leads people to desire additional children as an “insurance policy” for security in their old age. 3. Helping hands : In the agriculture setting children

can do work at a young age and will help support the family. In an industrial setting, the children are more of a luxury, in that they cost more

money than they bring in.

4. Importance of Education: When people go

through more education they will put off having children and thus they will have less reproductive

years. In addition, when children go to school they can not do the amount of work they would if

5. Status of Women: opportunities for women’s education and careers. : In the LDC’s most women are thought of as only

important for the number of children they can have. It is shown that the women that have an eighth grade education have half the

number of children as their counterparts. 6. Availability of

Contraceptives-Contraceptives are available in the

industrialized world and not very available in the LDC’s. More than any other single

factor, lower fertility rates are correlated with the percent of the population using

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Conclusion

 The human population is larger than at any other time

 Rates are decreasing but populations are still rising

 Most developed nations have passed through the demographic transition

 Expanding women’s rights slows population growth

 How will the population stop rising?

 The demographic transition, governmental intervention, or disease and social conflict?

QUESTION: Review

What has accounted for most of the world’s population

growth in recent years?

a) Women are having more babies.

b) Technology, medicine, and food have decreased death rates.

c) Fewer women are using contraceptives.

QUESTION: Review

According to the

I



P



A



T



S

formula, what would

happen if China’s 1 billion people had a lifestyle like

that of Americans?

a) Their population would automatically drop.

b) Their population would automatically increase.

c) Their affluence and technology would increase.

QUESTION: Review

Where is the highest

density

of people found?

a) In the colder climates (e.g., Siberia)

b) In temperate or tropical biomes

c) In rural areas

QUESTION: Review

An age structure diagram shaped like a pyramid with a

wide base shows a/an ________ population.

a) increasing

b) decreasing

c) stable

QUESTION: Review

Describe the relationship between population growth

rates

and population

size

.

a) Falling growth rates automatically mean a smaller population.

b) Falling growth rates automatically mean a larger population.

c) Falling growth rates mean we no longer have a population problem.

d) Falling growth rates do not mean a smaller

QUESTION: Review

Pre-industrial societies tend to have higher growth

rates because

a) good medical care prevents infant mortality.

b) there is little opportunity for women to get an education or employment.

c) governments provide social support networks for the elderly.

QUESTION: Weighing the Issues

Should the United States fund international

family-planning efforts?

a) Yes, absolutely.

b) Yes, but only in nations that follow U.S.-approved programs.

c) Only if it can influence the nations’ policies.

QUESTION: Weighing the Issues

Would you rather live in a country with a larger

population or smaller population?

a) Small population, so there will be more resources for me

b) Small population, so there will be more resources for others, including wildlife

c) Large population, so I can find a date

QUESTION: Interpreting Graphs and Data

What happens during the “transitional” stage of the

demographic transition?

a) High birth and death rates rise—population increases

b) High birth and death rates—population is stable

c) High birth rates with low death rates—

population increases

d) Low birth and death rates cause—

QUESTION: Interpreting Graphs and Data

According to this age pyramid, Nigeria’s future

population will be

a) balanced.

b) larger.

c) much larger.

d) smaller.

QUESTION: Interpreting Graphs and Data

According to these graphs, which countries had

access to family planning?

a) Iraq and Pakistan c) Malawi and Kenya