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The Dynamics of Demography

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					16.1- The Dynamics of
     Demography
  World Population as of April 4th-


     U.S.=    311,102,715
     World= 6,910,069,650
      The Changing Population
   Population- a group of people living in a
    particular place at a specified time

   Demography- the scientific study of
    population
 Factors of Demography: Fertility
           a measure of the number of
 Fertility-
 children born to a woman or a
 population of women

           the maximum rate at
 Fecundity-
 which women can physically produce
 children
 Hutterites- came to North and
  South Dakota and Canada from
  Switzerland in the 1930s and
  averaged more than 12 children
  each
 Good example
  of natural fertility-
  the number of
  children born to
  women in the
  absence of birth
  control
            World Record
 The greatest number of children born to
  one woman is 69. The 'lucky' lady was a
  Russian peasant who gave birth to
 16 pairs of twins,
 seven sets of triplets and
 four sets of quadruplets
 Occurred between 1725 and 1765. She
  also holds the world record for giving birth
  to the most sets of twins and sets of
  quadruplets.
               Measuring Fertility
   Crude Birth Rate- the annual number of
    live births per one thousand members of a
    population (crude= rough estimate)
    – CBR = Number of Live Births/Total Population * 1000
    – Based on entire population and ignores age structure
          World: 20 per 1000
          United States: 14 per 1000
          Niger: 51 per 1000
          Germany: 8 per 1000
 Fertility Rate- the annual number of live
  births per 1000 women aged 15-44
 Total Fertility Rate- average number of
  children born to a woman during her
  lifetime
   – Range from 1.4 (Europe) to 5.2 (Africa)
    Factors Influencing Birth Rate
   Health
     – widespread disease can cause miscarriages
       (German measles, rubella)
   Social
     – Average age of marriage
     – Economic development
     – Availability and use of contraceptives and
       abortion
     – Women in the work force
     – Social attitudes towards
       reproduction
Factors of Demography: Mortality
 Mortality- refers to deaths w/in a
  population
 Life span- the most advanced age to
  which humans can survive

   Life expectancy- the average number of
    years that persons in a given
    population born at a
    particular time can
    expect to live
     – World- 68 years
Oldest Man & Women To Ever Live
   Jeanne Louise
    Calment – 122
    years, 164 days


 Japanese   man-
    120 years, 237
    days
            Measuring Mortality
   Crude Death Rate- the annual number of
    deaths per thousand members of the
    population
    –   CDR=number of deaths/total population *1000
    –   Worldwide average: 9 per 1000
    –   United States: 8 per 1000
    –   Lesotho: 25 per 1000, 23% of adults ages 15-
        24 have AIDS
   Infant Mortality Rate- the # of infant
    deaths (under one year old) per 1000 live
    births
Factors of Demography: Migration
   Migration-The movement of people from
    one geographic area to another
     – Internal vs. external
         Measuring Migration
   Gross migration rate- the annual
    number of persons who enter or leave a
    geographic area per 1000 members

   Net migration rate- the annual increase
    or decrease per 1000 members of a
    population resulting from migration into
    and out of the population
    – Can be positive or negative
    – United States- 3.0 per 1000 in 1999
    – Only refers to legal immigrants
16.2- World Population
The Problem of Population Growth
   Rapid world population growth is a relatively
    recent phenomenon.

   1 A.D.- 250 million
   1650- 500 million
   1850- 1 billion
   1930- 2 billion
   1976- 4 billion
   2025- 8 billion

   Doubling time has diminished significantly.
      Why is the world’s population
            growing so fast?
   Population follows the principle of exponential
    growth
    – 2,4,8,16,32
   If a
    population
    is growing at
    1%, it takes
    70 years to
    double.
             Population Growth
 Your grandparents have
  seen more population
  growth in their life time
  than has occurred in the
  past 4 million years!
 Why?
    – Doubling time is getting
      shorter and shorter
   Fold a piece of paper in ½
    until you cannot do it
    anymore. Keep track of
    the # of folds.
    – Represents exponential
      growth
       Population Growth
 Asthe population doubles it becomes
 more difficult to double, requires
 more strength.
 This represents the difficulty of
 meeting the needs of a doubling
 population. It stresses existing
 resources and infrastructure.
             Robert Malthus
 Unchecked growth stresses &
  will surpass the food supply.
 Checks on growth:

   – Positive- famine, disease, war
   – Preventative- birth control,
     longer to marry, abstinence
     back then.
 For the poor extra income eaten
  up by extra births, lowers
  standard of living.
 Wealthy/educated exercise
  preventative checks
            Malthus Continued
   Wealthy already exercise preventive
    checks.

   Positive checks on population could be
    avoided through education of the poor, who
    would raise their standard of living and
    choose to have smaller families.

   Known for his dire predictions that
    overpopulation would lead to famine
    and poverty
        The Demographic Transition
                Theory
                                          Stage 1:
                                            – High birth and death
                                              rates
                                          Stage 2:
                                            – Beginning of
                                              modernization. High
                                              birth rates, death rate
                                              drops due to
                                              technological advances.
                                          Stage 3
                                            – Sharp decline in birth
                                              rate, but growth is still
                                              rapid because death
                                              rates are low.
                                          Stage 4
This theory explains that population
                                            – Slow growth if any
growth is a function of the level of
                                            – Anglo-America, Europe,
economic development in a country.            and Japan
Future World Population Growth
 After more than 200 years of
  increase, the annual population
  growth is declining after peaking in
  the late 1960s
 Rate is projected to drop to zero by
  2100
 World’s population will still continue
  to increase
            Population Control
   The conscious attempt to regulate
    population size through national birth
    control programs

   Most societies in the past have been concerned
    with increasing populations.
   Since the 1950s, some nations have begun to
    view high birth rates as a threat to national
    well-being and by 1990 most have programs in
    place to reduce birth
    rates.
   Range from voluntary
    to compulsory
    Voluntary Population Control
   Also called family planning
   Governments provide information and services
    that help couples only have the number of
    children they want
     – Family planning education, distributing birth
       control
   Only enables families to achieve their desired
    family size
     – 7.1 children in African
       nations
    Success of Voluntary Population
                Control
   In order to be successful, must take the
    broader social context into account
    – Effective ways to communicate
    – Religious and cultural opposition to birth
      control
   India: not effective until 1976 when the
    government turned to sterilization
    – Did not force by law, but used disincentives
    – Without official proof of sterilization people
      were denied business permits, gun licenses,
      ration cards, etc/
Success of Compulsory Population
            Control
   China and Singapore have forced population
    policies
   China was able to reduce its total fertility rate
    from 7.5 in 1963 to 1.8 in 2001
     – One child families receive a
       larger retirement pension,
       school admission for their
       children, and employment.
       Families with more children
       are taxed per child.
   Can make a difference.
Population Pyramids
Population Pyramids
 Zeropopulation growth: when
 deaths are balanced by births so that
 the population does not increase.
Ch. 16 section 3

Urban Transition
 When   does a village become a city?

How many people are required?
 TheUS Census Bureau counts
 population of 2,500 people or more.

      dense/permanent
 City:
 concentration of people in a specific
 area working in mostly
 nonagricultural jobs.
 What   is urbanization?
 Urbanization:  process by which an
 increasing portion of the world’s
 population lives in cities.

				
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