560 likes | 570 Views
APES Chapter 12 . Human Populations. Key Points. How is population size affected by birth, death, fertility, and migration rates? How is population size affected by the percentage of males and females at each age level? How can population growth be slowed?
E N D
APES Chapter 12 Human Populations
Key Points • How is population size affected by birth, death, fertility, and migration rates? • How is population size affected by the percentage of males and females at each age level? • How can population growth be slowed? • What successes have India and China had in slowing population growth? • How can global population growth be reduced?
Factors Affecting Human Population Size • Three factors influence population growth • Births, deaths, and migration. • Population change calculated by • population change = (births + immigration) – (deaths + emigration) • Instead of using total numbers they use crude birth rate (number of live births per 1000 people in a population in a given year) and crude death rate (number of deaths per 1000 people in a population in a given year.
World’s Annual Population Change • Birth rates and death rates are coming down worldwide but death rates are falling faster than birth rates and therefore we are increasing in size. (approximately 216,000 new people each day, most in LDC’s) • Rate of world’s annual population change (excluding migration) is expressed as: Annual rate of natural population change (%) = Birth rate - death rate X 100 1000 = Birth rate – death rate 10
Exponential Growth • Exponential growth has not disappeared but it has slowed down. • It dropped 42% from 1963 at 2.2% to 2002 at 1.28%. This is good! • However the population base increased 94%. This is bad! • This 1.28% increase may seem small but, it adds 79 million people to the world each year. • And with the large base it means 79 million people each year in 2002 whereas in 1963 it was only 69 million!!
Average Annual Increase in World’s Population1950-2002 and Projections to 2005
World Rates of Population Growth • China (1.28 billion) and India (1 billion) have the largest numbers of people and the largest bases accounting for 37% of the world’s population. (USA is third with 288 million people)
Changes in Global Fertility Rates • Two types of fertility: • Replacement level fertility: the number of children a couple must bear to replace themselves. • It is slightly higher than 2 children per couple (2.1 in developed countries and 2.5 in developing countries), mostly because some female children die before reaching their reproductive years.
Replacement Level Fertility • Does reaching replacement level fertility mean an immediate halt to population growth? • No!! Because so many future parents are alive. • IF each of today’s couples had an average of 2.1 children and their children also had 2.1 children, then the world’s population would continue to grow for 50 years or more (assuming death rates do not rise)
Total Fertility Rate • An estimate of the average number of children a woman will have during her childbearing years if between ages 15 and 49 she bears children at the same rate women did this year. • The TFR has dropped since 1950 • 2002 the global TFR was 2.8 children per woman. LDC’s is 3.1 and MDC’s is 1.6 • In 1950 it was 6.5 in LDC’s and 2.5 in MDC’s • This is good progress yet, it is still above the Replacement level fertility
Case Study: How Have Fertility Rates Changed in the United States • U.S. population has grown from 76 million in 1900 to 288 million in 2002 even though the country’s TFR has fluctuated wildly. • Our growth is still faster than any other developed country when include migration • In 2002 we increased 2.9 million: 1.7 million more births than deaths; 900,000 legal immigrants and refugees; and an estimated 300,000 illegal immigrants
Factors that Affect Birth Rates and Fertility Rates • Importance of Children as a part of the labor force • Urbanization • Cost of raising and educating children • Educational and employment opportunities for women • Infant mortality rate • Average age at marriage • Availability of private and public pension systems • Availability of legal abortions • Availability of reliable birth control methods • Religious beliefs, traditions, and cultural norms
Comparison of Basic Demographic Data for U.S., Canada and Mexico
Factors Affecting Death Rates • Large increase in the world’s population growth over the past 100 years is not the result of increase in crude birth rate but a decrease in crude death rates. • More people started living longer and few infants died as • Increased food supply and distribution • Better nutrition • Improvements in medical and public health technology • Improved sanitation and personal hygiene • Safer water supplies
Indicators of overall health of a people in a country or region • Two factors are good useful indicators of overall health • Life Expectancy: the average number of years a newborn infant can expect to live • Infant Mortality Rate: the number of babies out of every 1000 born who die before their 1st birthday.
Good News/ Bad News About Life Expectancy • Good news: Life expectancy at birth has increased globally from 48-67 years (MDC’s to 76 years and LDC’s to 65 years) • Bad news: in the world’s 49 poorest countries, mostly in Africa, the life expectancy is 55 or less. And declining due to AIDS.
Why Infant Mortality is the Single Most Important Measure of a Societies Quality of Life • High Infant Mortality Rate usually indicates insufficient food; poor nutrition, and high incidence of infectious disease. • Infant mortality rates have declined since 1965 from 20 per 1000 live births to 7 in MDC’s and from 118 to 60 in LDC’s.
Infant Mortality and the U.S. • Between 1900 and 2002 the U.S. infant mortality dropped from 165 to 6.8. This led directly to the increase in life expectancy. • However even though it is so low the U.S. has 37 other countries with lower Infant Mortality rates • Why is the U.S. rate so high in comparison? • Inadequate health care (mainly for poor women) • Drug addictions among pregnant women • High teenage birth rates
Good News/ Bad News About Infant Mortality in the U.S. • Good News: the U.S. birth rate among girls ages 15 – 19 has declined and was at it’s lowest since 1940. • Bad News: The U.S. has the highest teenage pregnancy rate of any industrialized nation; many of them end in abortion and those that actually go full term produce babies with low birth weight.
Population Age Structure • The proportion of the population of each sex at each age level. • Three age levels: • Pre-reproductive: 0-14 • Reproductive: 15-44 • Post-reproductive: 45-85+
How Does Age Structure Affect Population Growth? • When you have a wide base to an age structure (high pre-reproductive 0-14) you have a built in momentum for population growth. (as long as death rates do not rise) • This will continue to support population growth even if the population reaches Replacement Level Fertility. • In 2002, 30% of the population of the World was pre-reproductive.
Worldwide Population Age Structure Comparisons • Populations have stabilized in Japan and the European countries yet, population size is expected to double or triple before stabilizing in LDC’s is reached. • We live in a demographically divided world of the haves and have nots. • We can use these age structure diagrams to make economic as well as population projections for the future. As seen through the U.S. age structure and the baby boom over time.
Economic Effects of Baby Boomers and Future Generations • With about half the population of the U.S. baby boomers influence: • The goods and services market. • Who is elected and what laws are passed. • Creating a 50 something and 60 something market. • Influence the baby-bust generation (Gen. X) to pay higher taxes (Social Security, health-care, and income) to support baby boomers.
Baby Bust and Echo Boom • Baby bust should have things easier in some respects than baby boom such as; opportunities for education, jobs, services, and labor shortages may drive up wages because less people competing. • However; difficult to get job promotions as the baby boomers mature and hold many higher level positions later in life due to advanced health care, later age for Social Security, and need to accumulate retirement funds. • Echo Boom is the largest generation ever and will soon have more economic power than baby boom parents.
Some Effects of Population Decline From Reduced Fertility • Increase in the percentage of people over the age of 60. • Increase in social services and health care requirements. • Decrease in the needed worker base to sustain such programs. • By 2050, 39 countries including Japan, Germany, Italy, Hungary and Ukraine will be smaller than today.
Effects of Population Decline From Rise in Death Rates • HIV/AIDS kills more young adults while hunger and malnutrition kill the infants and children. • AS the young adults age structure shifts due to the deaths caused by AIDS reslut are: • Drop inaveragelife expectancy • Loss of young adult workers and trained personnel • Ris in the number of orphans • Drop in food production
Solutions: Influencing Population Size • Migration is limited in most countries, only Australia, Canada, and U.S. allow large increases each year.
Solutions: Influencing Population Size Birth rates: Many believe that the earth has already exceeded it’s carrying capacity. Others believe we may be able to go to 20 billion people. Take the increasing life expectancy as a reason. How do we sustain the growth of the population without endangering the environment more. We fail to provide the basic necessities today for one of every six people. How are we going to support 3.9 billion more people by 2050.
How Can Economic Development Help Reduce Birth Rates • Demographic Transition
Family Planning Reduces Birth Rates and Abortion Rates • Advantages of Family Planning: • Increase the proportion of married women in developing countries who use birth control • 50% drop in TFR since 1950 • Reducing the number of legal and illegal abortions • Decreasing the risk of death form pregnancy Unfortunately, 42% of all pregnancies in LDC’s are unplanned and 26% end in abortion. Many women, 250-350 million, want to limit the number and determine the spacing of their children, but they lack access to services.
Family Planning Reduces Birth Rates and Abortion Rates • Future Goals: • Expanding family planning to include teenagers and sexually active unmarried women who are often excluded. • Pro-choice and por-life groups to join forces in greatly reducing unplanned births and abortions, especially among teenagers • Programs to educate men about having fewer children and taking more responsibility for raising them • Increased research on developing new, more effective, and more acceptable birth control methods for men
Empowering Women to Reduce Birth Rates • Women tend to have fewer children when they have access to education and jobs outside the home and live in societies in which their rights are not suppressed. • Most analysts believe that women everywhere should have full legal rights and opportunity to become educated and earn income outside the home. • Not possible without a great deal of social changes in many of the male-dominated societies of today.
Economic Rewards and Penalties to Reduce Birth Rates • Many couples in developing countries want 3-4 children, well above RLF. • Analysts suggest that one way to get them to downsize is offer economic rewards or penalties to help slow growth. • About 20 countries offer small payments to people who agree to use contraceptives or to be sterilized, yet many who do this have already had all the kids they want.
Economic Rewards and Penalties to Reduce Birth Rates • Some countries penalize couples for having too many kids, like China. • Penalties range from raising taxes, charging fees, or eliminating tax deductions for a couple’s third child (Singapore, Hong Kong, Ghana) • Penalties may also include loss of health care benefits, food allotments, and job opportunities.
Economic Rewards and Penalties to Reduce Birth Rates • These work best if • They encourage (rather than coerce) people to have fewer children • Reinforce existing customs and trends toward smaller families • Do not penalize people who produce large families before the programs were established • Increase a poor family’s economic status.
Case Study: India • India: First family planning program in 1952. • Since then population has still increased. • And they continue to face serious malnutrition, poverty, and environmental damage. ( see list on pages 272-273) • Many of it’s proponents are disappointed even though without the program the conditions would be worse. Many problems arose from the family planning program: poor planning, bureaucratic inefficiency, the low status of women( even though guaranteed equality), extreme poverty and lack of administrative support and financial support.