Human Population

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Human Population

• Dynamics and Regulation

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Outline

• Human Population Changes
• History
• Demographic Transition
• Reasons why population change
• Population Growth Rates
• Over time
• Over space
• Population size determinants
• Carrying capacity
• Birth and Death
• Case Studies

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Rapidly increasing human population due to?
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Rapidly increasing human population, due to

• Decreased Death Rate
• that resulted from
• Better nutrition
• increased food production
• improved distribution
• increased food varieties
• Less Disease
• better sanitation
• safer water
• medical care (antibiotics, vaccines, pesticides)

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Human population is increasing rapidly
Important questions to consider regarding this
factual statement

• Are there geographic differences in population
  growth rates?
• Where is population changing the fastest?
• Where is population stable?
• What lessons can we learn from these places to
  help us reach a stable population? recognizing
  reality of carrying capacity

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Average Annual Rate of Population Change, Figure
12-4
Something is different between these locations!

• Regions
• Europe, Australia, Russia, China, US, Canada
• Much of S. Am. India, Iran
• Mexico, Ecuador, Peru, Boliva, Iraq, Pakistan,
  s.Africa
• central Africa, some of west Africa, Madagarscar

• Population Growth
• lt1
• 1-1.9
• 2-2.9
• gt3

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Sweden
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Demographic Transition

• In MDCs, after death rate declined due to
  industrialization, birth rates declined about 100
  years later
• this is called the
• DEMOGRAPHIC TRANSITION
• FIGURE 12-17, 12-25

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Demographic Transition

• Is a hypothesis that countries, as they become
  industrialized, have declines in death rates
  followed by declines in birth rates.
• Has been seen in every industrialized country
  (MDCs), after the death rate has declined for a
  long period of time (gtgeneration).

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Why does the birth rate drop?
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Why does the birth rate drop?

• Economic Well-being
• children not needed for labor force.
• cost of rearing and educating children is high.
• Pension systems to support parents in their old
  age.
• Paid employment for women.
• Infant mortality drops
• therefore you are sure the children you have will
  survive.

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National Infant Mortality Rates, Figure 12-18

• Infant Deaths/1000 Live Births
• lt 10
• 11-35
• 36-70
• 71-100
• gt100

• Regions
• N.America, W. Europe, Australia
• Mexico, most S. Am., Eastern Europe, China,
  Russia, central Asia, most Middle East
• Bolivia, most northern southern Africa, India,
  Indonesia
• Central and Eastern Africa, Pakistan, Myanmar
• Somalia, Mozambique, Angola, Iraq, Afghanistan,
  Sierra Leone, Liberia, Cote dIvorie, W. Sahara,
  Congo, Laos

Geographic pattern same as in population growth
rate table
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Period In-between (from start of death rate
decline to end of demographic transition)

• A time of tremendous growth in population size!!
• This is the growth the LDCs are currently
  experiencing.

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Why difference between Developed and Developing
in population size??

• 1. Developing countries started industrialization
  later.
• And had a larger population base when they did
  industrialize, which lead to more serious
  impediments in industrialization.
• 2. Most developing countries had higher birth
  rates going into industrialization
• (higher death rates, tropical diseases)

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Why difference between Developing and Developed
countries in population size?? (cont)

• 3. Excess population of Developed countries
  exported (reduced stress on industrialization).
  No place for excess Developing countries
  population to go.
• 4. Developed countries --gt abundant natural
  resources at a time when technology was
  developing. Developing countries faced with
  large population pressing on resource base, and
  Developed use of resource base, at time of
  industrialization.

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Results of this growth rate
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VIDEO BREAK
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Human Population
What's the Future?
What type of data do you need to know to predict
the future regarding human population size?
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Components to Population Dynamics

• Carrying Capacity
• Growth Rate Birth Rate - Death Rate

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? Components in Human Carrying Capacity

• Food
• food production has been increasing, however per
  capita food production has been level (grains,
  fish catch)
• 1950--1990 food production increased by 2.6/year
• 1990-1996 food production increased by 0.7/year
  (pop. increase 1.55/yr)
• Possible changes in future?
• Biotechnology could increase production
• Water shortages and farm plot fragmentation could
  decrease production
• Water
• water scarcity is growing concern, most
  dramatically in countries with high growth rates
• Per capita world irrigated area declining since
  1978
• Areas of US Breadbasket changing to dryland
  agriculture

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Birth Rates but first, some Terminology

• Fertility
• measure of actual numbers of offspring produced
  by fecund individuals
• Age Structure
• distribution of population between age classes
• determines expected population growth patterns

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Population Growth Momentum

• More individuals in the pre-reproductive age
  class, you will have the population increase.
• If the age structure is pyramid-shaped, you will
  have GROWTH
• See Fig. 11-13

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? Human Birth Rates

• Developing Countries two patterns
• Smaller families, higher standards of living (E.
  Asia)
• Fertility changing more slowly, low standards of
  living (sub-Saharan African and India)
• Human replacement fertility level
• 2.1-2.5 offspring/female (why the range?)
• U.S fertility rate is 1.8 to 1.9 but US
  population is still growing. Why?
• 1. Immigration
• 2. Age structure (population growth momentum)

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Age Structure, Indonesia1997
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Age Structure, Indonesia2050
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Age Structure, Nigeria1997
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Age Structure, Nigeria2050
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Age Structure, Italy1997
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Age Structure, Italy2050
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Zero Population Growth

• Two Requirements
• 1. Replacement fertility level has been reached.
• 2. No existing population growth momentum.

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Projected Population Growth, Developing
Countries, 1999 to 2050

• Countries that have slowed growth
• S. Korea 11
• Taiwan 14
• Thailand 21
• Countries that have not slowed growth
• Ethiopia 177
• Nigeria 124
• Pakistan 127

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? Human Death Rates

• Problems with an increase in death rate? With an
  increase in death rate in the developing
  countries?
• Ethical issues
• Global economy
• Illegal immigrants
• Instability effects (e.g., Middle East)
• Habitat Loss
• Global pollution impacts

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Human Death Rates

• Between 1996 and 1998, UN population projection
  for 2050 reduced from 9.4 billion to 8.9 billion.
• Half the reason lower fertility
• Other half deaths from AIDS

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HIV Infection Rate

• Percent of Adult Population Infected
• Zimbabwe gt26
• Botswana gt25
• South Africa gt22
• Namibia gt18
• AIDS kills those in the most productive years of
  their lives
• orphans and the elderly left behind
• Life Expectancy declining
• Botswana 61 yrs in 1990 44 yrs in 1999

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Not Happy News But...

• Now well talk about actual, successful
  population control programs and the lessons they
  provide.

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Case Study

• China

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Background on China

• 1st census in 1953 580 million people
• Policy maximize the health and well-being of
  every child born.
• Famines in 50s and 60s as many as 30 million
  died
• 1970 government estimate country could support
  650-700 million, but there was already gt 1
  billion people
• 7 of worlds arable land and water 20 of the
  worlds people

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Chinas Population Policies

• Late 60s
• birth control accessible to all.
• Health care system for rural poor.
• Increased access for education and jobs for
  women.
• Social security provided.
• 1970s
• Later, Longer, Fewer

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Later, Longer, Fewer

• Legal age for marriage increased from very young
  to the early 20s (LATER)
• Longer maternity leaves and other benefits to
  families that followed the population policy
  (LONGER).
• Promoted FEWER children

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Chinas Population Policy (cont)

• 1979 One child per Family restrictive family
  planning program
• worked better in the cities than in rural areas.
• Benefits to families who pledge one child policy
  better housing, food, pensions, medical care,
  salary bonuses, free tuition for one child
• Political and community leaders (elite) followed
  policy as well
• 1987 China began to relax one child policy, in
  favor of delayed second child (8-10 years apart).
  
• 1996 fertility rate 1.8 (down from 5.7 in 72)

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Data from country demographics from
http//www.census.gov/ipc/www/idbsum.html/
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Would a China-style system of family planning
work elsewhere?
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Largest Five Countries?
1998
2050

• 1,478,000
• 1,529,000
• 349,000
• Pakistan 345,000
• Indonesia 311,000
• Nigeria 244,300
• Brazil 244,000

• China
• India
• U.S.
• Indonesia
• Brazil

• 1,255,000
• 982,000
• 274,000
• 206,000
• 166,000

In thousands
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India Two Divergent Experiences

• India as a whole
• first with a national family-planning program
  (1952, population size 400 million)
• Not very effective initially
• poor planning
• mistrusted because of coercion
• low status of women
• lack of administrative and financial support
• no pension system
• 75 of population is rural 80-90 female rural
  population is illiterate.

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India Divergence Experiences

• State of Kerala, India
• economic redistribution dramatically improved
  quality of life even though very poor by
  conventional measures
• GDP only 340

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• State of Kerala, India
• economic redistribution provided education and
  health care to all choose self-reliance and
  economic redistribution, not external loans and
  economic growth

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Status of Women and Fertility Rates

• If only role women have to play is that of
  mother, they will have many children
• If importance of female is based on number of
  sons she produces, she will produce many
  children.
• Clear connection between womens status and
  womens fertility.
• Access to birth control

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Gag RuleHelpful or Hurtful for Population
Control?

• The first major announcement of the Bush
  administration reinstated the "global gag rule."
• The rule bars U.S. funding for any organization
  that uses its own non-U.S. money to provide legal
  abortions or talks to patients about the
  availability of legal abortions or talks about a
  specific country's abortion law.
• The administration claimed that it wanted to
  block "taxpayer funding" of abortion overseas and
  that it wanted to make abortion more rare.
• However, no U.S. funds are used to provide
  abortions anywhere in the world. A 1973 federal
  law prohibits such funding.

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Cultural Attitudes Important

• Attitude towards females critical
• Religion may play a role.
• HOWEVER, country with highest percentages of
  Roman Catholics (Italy) also is the country with
  one of the LOWEST fertility rate (1.1).

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Global Average Fertility

• 1950s 5 births/woman
• 1998 2.7 births/woman
• Fertility declining in all regions of the world
  during last 25 years
• Asia 5.1 to 2.6
• Africa 6.6 to 5.1
• Latin America and the Caribbean 5.0 to 2.7

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Outlook?

• US Population on 2/2/2004, at 725 AM EST was
  292,503,187 people.
• 2/7/01, at 747 am, 283,579,266 people
• one new person, every 17 seconds.
• World Population on 2/2/2004, at 726 am EST was
  6,345,759,176 people.
• 2/7/01, at 747 am, 6,127,033,019 people
• Data from US Census Bureau, http//www.census.gov/
  main/www/popclock.html

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Outlook?

• US Population on 2/5/2001, at 723 AM EST was
  283,567,802 people.
• 2/7/01, at 747 am, 283,579,266 people
• one new person, every 17 seconds.
• World Population on 2/5/2001, at 723 am EST was
  6,126,606,439 people.
• 2/7/01, at 747 am, 6,127,033,019 people
• Data from US Census Bureau, http//www.census.gov/
  main/www/popclock.html

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Forecasted probability that population will start
to decline at or before the indicated date, from
Lutz et al., The end of world population growth.
Nature 412, 543 - 545 (2001)
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Low fertility 2.3 billion Medium fertility 9
billion High fertility 36.4 billion At current
fertility levels - 134 trillion
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Ten Most Populous Countries

• 1996
• 1.22 billion
• 950 million
• 265 million
• 201 million
• 161 million
• 148 million
• 134 million
• 126 million
• 120 million
• 104 million

• 2025
• 1.5 billion
• 1.38 billion
• 335 million
• 277 million
• 202 million
• 153 million
• 233 million
• 126 million
• 176 million
• 246 million

• Countries
• China
• India
• US
• Indonesia
• Brazil
• Russia
• Pakistan
• Japan
• Bangladesh
• Nigeria