Chapter 6 Outline 6.1 and 6.2
Human Population Growth: A Brief History
A.
The human population has grown rapidly. Why?
3 reasons
B.
Population growth has slowed but when do we
overshoot k?
C.
No population can continue to grow indefinitely.
High
High
10.6
Medium
Low
Medium
8.9
Low
7.2
Year
Fig. 9-2, p. 173
D. Human population to natural capital
The 2005 Millennium Ecosystem Assessment concludes
that human activities have degraded about ______% of
the earth’s ecosystem services.
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What are some ways in which we have degraded natural
capital?
Explain cultural carrying capacity.
Factors Affecting Human Population Size
A.
[Population change = (______________) –
(________________)]
1. The ____________ is the number of live births per
1,000 people in a population in a specific year.
2. The ____________ is the number of deaths per
1,000 people in a population in a specific year.
B.
There are currently more births than deaths
throughout the world.
1. The ___________________________ (%) = birth
rate- death rate divided by 1,000 persons multiplied
by 100.
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C.
___________is the number of births that occur to
an individual woman or in a population.
a. ___________________ is the number of children
needed to replace their parents. 2.1 in developing
countries
b. ____________ (TFR) is the average number of
children that a woman has during her fertile years.
 The replacement level to sustain a population is ___
children.
 In 2006, the average global Total Fertility Rate was
_____ children per woman.
 ______ in developed countries down from 2.8
since 1955).
 _______ in developing countries (down from 6.2
in 1955).
Average global TFR in 2012 was _____ children per
woman
Global TFR will have to drop to ______ to halt
population growth
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D.
U.S. grew from 76 million in 1900 to 314 million
by 2012
From 1946-1964 U.S. ____________ period. TFR
peaked at 3.7
The baby bust that followed the baby boom was largely
due to delayed marriage, contraception, and abortion.
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1. The population growth of the U.S. is greater than
other developed country even though the drop in
TFR has slowed the rate of population growth in the
U.S.
2. ________ million people were added to U.S. in
2012- _____% from immigration.
47 years
Life expectancy
77 years
8%
Married women working
outside the home
81%
15%
High school
graduates
83%
10%
Homes with
flush toilets
Homes with
electricity
Living in
suburbs
Hourly manufacturing
job wage (adjusted for
inflation)
Homicides per
100,000 people
98%
2%
99%
10%
52%
1900
$3
2000
$15
1.2
5.8
Fig. 9-7, p. 176
F.
Many factors influence birth and fertility rates.
(list and describe 9 factors)
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G. Rapid growth of the world’s population over the past
100 years is primarily in the result in the decline in
death rate.
What factors are causing a decline in death rates?
H. An indicator that measures of overall health is Life
expectancy.
Average global life expectancy increased from 48 to
_____ years from 1955 to 2012
Japan – 83 years
U.S. – ___ years
What is infant mortality rate?
What are the main causes of a high infant mortality
rate?
(Read the jet airliner analogy on page 129)
US infant mortality rate is ___th among other
countries (What are the two main reasons)
I. ___________ is the movement of people into
(__________) and out of (__________) an area.
Who are environmental refuges and how many are
there?
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Population Age Structure
A. Three categories
1. Pre-reproductive ages span birth to 14 years of age.
2. Reproductive ages include 15 through 44.
3. Post-reproductive ages include ages 45 and up.
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B.
The major determining factor in a country’s future
population growth is the number of people under the age of
15. - In 2004, 30% of the planet’s population was under 15.
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C.
Changes in the distribution of a country’s age groups
have long-lasting economic and social impacts. - ‘baby
boom’ generation in the U. S.
1. Dominate the population’s demands for goods and
services.
2. Influence elections and legislation and economic demand.
3. Retirement of baby boomers in the U.S may create a
shortage of workers.
D. The ‘baby bust’ generation compared to that of the ‘baby
boom’. (3 to 4 impacts)
E. Consequences of reduced fertility and population decline (3
consequences of an older population)
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F. Serious consequences of population decline due to death.
(give an example)
Solutions: Influencing Population Size
Can the world sustain a rising population without causing widespread
environmental damage?
1. More consumers = more growth, and people are the world’s
resource as consumers and as problem solvers.
2. Some feel that limiting population is a violation of their religious
beliefs.
3. The world is already overpopulated.
a. Basic necessities of life are not provided for one out of six
people today.
b. Declining health and environmental conditions will threaten the
entire world.
c. Increased resources use and environmental harm is
compromising the life of the environment through: infectious
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disease, biodiversity loss, fisheries depletion, water scarcity,
pollution, and climate change.
d. The quality of life on the planet and for all its people requires
some limits on everyone.
The demographic transition hypothesis states that as countries become
industrialized, first their death rates and then their birth rates decline
in four stages
1. The pre-industrial stage produces high birth and death rates because
living conditions are harsh.
2. The transitional state sees food production rise and improvement in
health care. Death rates drop and birth rates remain high.
3. The industrial stage causes the birth rate to begin to drop and the
death rate drops because of industrialization, medical advances and
modernization are widespread.
4. The postindustrial stage moves to the birth rate equaling the death
rate and resulting in zero population growth. Population size will
begin slowly decreasing.
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Some countries run the risk of getting caught in the transitional state and
economic conditions will not be available to sustain the population.
1. There can be a shortage of skilled workers to sustain the country’s
economy.
2. There will not be capital and resources to support rapid developing
economies.
a. International debt takes much of a country’s resources.
b. Developed countries are not helping developing countries
economically.
Family planning helps reduce the number of births and abortions
throughout the world.
1. Information is given on birth spacing, birth control, and health care.
2. Family planning has been responsible for at least 55% of the drop
in TFRs in developing countries.
3. Family planning has also reduced both legal and illegal abortions
per year.
4. Services come through educational and clinical services.
a. Almost one-half of pregnancies in developing countries are
unplanned and 26% end in abortion.
b. Women want to limit their pregnancies but have no access to
contraceptives.
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5. Family planning success can be improved through these methods:
a. Target programs to teenagers and unmarried, sexually active
women.
b. Develop programs for educating men about their responsibilities
for the children they father.
c. Provide more effective means of birth control for men.
d. Advocate that pro-choice and pro-life groups join to reduce
unplanned birth and abortions.
6. Empower women by providing education, paying jobs, and support
their human rights.
Reducing population growth can best be achieved by investing in
family planning, in reducing poverty, and elevating the status of women.
Slowing Population Growth in India and China
A. India has tried to control its population growth for years.
1. Overpopulation ills of poverty, malnutrition, and environmental problems abound in India.
2. Almost one-half of India’s labor force is unemployed; half of its cropland is degraded due to
soil erosion; 2/3s of its water is seriously polluted, with inadequate sanitation services.
3. Efforts to limit population have not been especially successful because:
a. Poor couples believe they need several children for work and care.
b. There is a strong preference for male children so many do not use birth control.
B. Population growth in China has been controlled by a strongly enforced government program.
1. Between 1972-2004, China’s birthrate was cut in half.
2. Couples with one child are rewarded with extra food, larger pensions, better housing, bonuses,
free school tuition, and preferential employment treatment for the child.
3. 83% of married women use modern contraception, provided free by the government.
4. China’s population has an enormous environmental impact that may affect its production of
food.
5. The health clinics that used to provide basic health care for rural farm population collapsed in
the 1980s, now 9 of 10 rural Chinese have no health insurance or social safety net
Human Impacts on Natural Systems
A. Humans have altered nature in ways that threaten the survival of many species including our own
species.
1. Humans have directly affected changes on about 83% of earth’s land surface.
2. Humans have altered nature to meet needs and wants in nine major ways.
a. Destruction, fragmentation, and degrading of wildlife habitats have reduced biodiversity.
b. The simplification and homogenization of natural ecosystems by clearing land and planting
a single species (monoculture) reduces numbers of species and interactions.
3. Alteration of natural ecosystems needs to be slowed down and we need to maintain a balance
between simplified, human-altered ecosystems and more complex natural ecosystems.
B. By learning how the earth works and work with its natural processes, we can increase our own
quality of life.
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Summary
1.
Birth, death, fertility, and migration rates are the factors that determine population size. As birth rates
have declined in developed countries, population has increased due to people’s migrating into these
countries. Women’s fertility rates have dropped but are still above the replacement-level fertility
around the world.
2.
Population size is profoundly affected by age structure. If women are past their primary child-bearing
ages, population increase will be limited. If, however, the population has a large percentage of young
women entering their childbearing years, the potential for large population increases is present. In
general, the closer a country’s young women are to 15-40 years of age, the more potential for a
rapidly increasing population.
3.
We can influence population size by encouraging smaller families, by encouraging adoption of
children already born and discouraging new births. Population size is, also, affected by health care or
its lack; by epidemics (such as AIDS); by losses through war, etc. Lack of prenatal care for expectant
mothers, failure to protect children from communicable diseases (like measles) or wide-spread
diseases (like malaria) can contribute to a smaller population. In the past economic development,
family planning, and economic opportunities for women have reduced birth rates.
4.
India and China have both made efforts to control their population growth. China has been more
successful because, as a dictatorship, it has imposed restrictions on family size with rewards and
punishments for those who support or defy the government’s direction. India, without a policy of
coercion, has reduced its birth rate; but the wish for male children and several child for the care of old
parents has helped to maintain a growing population.
5.
The most effective method to slow the growth of world population is to invest in family planning,
reduce poverty and elevate the status of women.
More Depth: Conceptual Term Paper Topics
1.
Population growth: a case study of Mexico, China, India, Kenya, Japan; the geography of global
population distribution; infant mortality trends and issues; illegal immigration into the United States;
marriage age trends; fertility trends and the women's rights movement; factors influencing family size
preferences; Earth's carrying capacity; family planning.
2.
Population growth in the United States: economics of fertility control technology in the United
States, economic costs of childrearing in the United States, new birth control methods, teenage
pregnancy in the United States
3.
Influencing population size: case studies of India, China, Japan, Thailand.
4.
Demographic transition: past, present, and future.
Environmental impacts of population: air pollution in urban areas; land degradation from urban sprawl;
deforestation and desertification in developing countries.
More Breadth: Interdisciplinary Activities and Projects
1.
Invite a public health official or nutritionist to your class to explain the factors involved in the decline
in the global death rate over the past century and the decline in the infant mortality rate in the United
States. Why is the latter rate higher in the United States than in many other developed nations?
2.
U.S. immigration policy had become a volatile political issue by the 1980s. Arrange a debate on this
subject. Debate the proposition that the United States should enact and strictly enforce legislation that
holds legal immigration to levels consistent with the achievement of ZPG within a few generations.
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3.
Ask your students to share with the class poems, short stories, songs, paintings, collages, photographic
displays, slide talks, or other works expressing their feelings about population issues and problems.
4.
Are family-planning clinics in your community that provide contraceptives and birth control
counseling? Invite a family-planning worker to visit your class and discuss different aspects of family
planning.
5.
Ask students to work with dynamic computer simulations (such as the Forrester-Meadows model).
Analyze the sensitivity of the model to initial assumptions (optimistic versus pessimistic).
Multisensory Learning: Audiovisuals
The Population Reference Bureau rents through the mail over 50 video tapes, films, and slide/tape
programs on population dynamics, the environment, and related topics. For a free list, send a selfaddressed, stamped envelope to the Population Reference Bureau. PRB.
Demography; 1994; 23 min.; human population demographics; FHS.
Extinction: End of the Line. 1991. 17 min. VHS/DVD. EVN.
The Human Race. 1995. 207 min. BFF.
Life Cycles. (Home Place series) 1998. 26 min. BFF
Paul Ehrlich and the Population Bomb; 1998; 60 min.; Ehrlich talks about the need to curb exponential
human population growth; FHS.
Population and Prosperity: Sustainable Lives, Attainable Dreams; 1994; explores population-related
environmental problems and effective strategies to solve them; NWF, item #79497.
Population: How to Make a Difference; 1994; population, development, and the environment; MDV.
Silent Explosion; 1986; 20 min.; 1986 video; PI.
World Population; 1990; 7 min; a depiction of human population growth from 1 AD and projected to 2020;
VP.
World Population; 6 min.; graphic simulation of the history of human population growth; ZPG.
World War III: Population Explosion & Our Planet. 1950. 50 min. VHS. VP.
CD-ROM
World Population Atlas File. 1998. A database and mapping system along with comprehensive activity
sheets, supporting international photographs and concepts; FHS.
ATTITUDES/VALUES
Assessment
1.
Do you feel the size of the human population is an important environmental issue?
2.
Do you feel consumption by the human population is an important environmental issue?
3.
Do you feel that humans have the right to have as many children as they want? Are there any limits
on this right? If so, what are they?
4.
Do you feel that there should be a national population policy? What steps would you support?
5.
Do you feel that teen pregnancy is a problem?
6.
Do you feel that women's roles are important in addressing population size?
7.
What are your feelings toward birth control? Population control?
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8.
Do you feel that the Earth will be able to sustain the projected increases in human population growth?
More Depth: Discussion and Term Paper Topics
1.
Do you think the United States needs a population policy? Should the federal government stop
subsidizing large families?
2.
Evaluate U.S. immigration policy.
3.
Do you think the United States should play a global leadership role in promoting stabilization of the
world's human population?
4.
Would you rather be a baby boomer or a baby buster?
(Also, see text, Critical Thinking, p. 189 and Critical Thinking and the Environment.)
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