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Human Populations

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  1. Human Populations Brita Christensen Carlye Richter

  2. Case Study • Every year, India adds more people to the world’s population than any other country • In 2005, India had 1.1 billion people • By 2050 India is estimated to have a population of 1.63 billion • A quarter of the population is already in poverty, with no food, homes, education, and jobs… how can the government fix the problem?

  3. Case Study… • The large population growth is India is due to lack of birth control and other contraceptives/sterilization • In 2000, the Indian government let each state choose how to handle the situation • Some states chose to focus on social justice while others adopted a more direct, interventionist policy

  4. Population Growth • Every second 4/5 children are born somewhere on Earth • In that same second, 2 people die • This makes a net gain of 2.3 million more humans per second in the world • Global population will double in 58 years • Most numerous vertebrate species

  5. Affects • Overpopulation will cause resource depletion and environmental degradation • Human ingenuity, technology, and enterprise can extend the world carrying capacity and allow us to overcome problems

  6. Human populations recently increased • 10,000 years ago the total world population was only a few million • After the agricultural revolution, population was able to grow very slowly • Population was held in check by disease and famine

  7. 1600’s • Human populations increased rapidly • Sailing and navigating skills stimulated commerce and communication between nations • Agricultural developments, sources of power, healthcare and hygiene

  8. Malthus and Marx • Malthus argued that human population increases exponentially and food production either remains stable or increases slowly • The only way to stabilize humans populations are to keep them in check with disease and famine • Followers are neo-Malthusians • Marx argued that in order to slow population growth and get rid of crime, starvation, and disease is social justice • Followers are neo-Marxians

  9. Technology • Scientific progress has allowed food supply to increase faster than population growth • Population growth is due to technology in agricultural productivity, engineering, information technology, commerce, medicine, sanitation, and availability of easily acquired natural resources

  10. Demography • Demos = people • Graphos = to write or to measure • Tells vital statistics about people such as births, deaths, where they live and total population size

  11. Demography facts • U.S. Census Bureau estimated 6.4 billion people in the world in 2005 • Highest populations growths occur at “hot spots” • Wealthier countries tend to have shrinking populations because many choose to have few or no children and life expectancy is longer

  12. Demography facts… • Russia is declining by nearly 1 million people per year because of a collapsing economy, hyperinflation, crime, corruption, and despair • African countries experience a population decrease because of AIDS

  13. Fertility • Crude birth rate- the number of births in a year per thousand persons • Total fertility rate- number of children born to an average woman in a population during her entire reproductive life • Zero population growth- occurs when births plus immigration in a population just equal deaths plus emigrations

  14. China • One-child-per-family policy decreased the fertility rate from 6 in 1970 to 1.8 in 1990 • Resulted in abortions, forced sterilizations, and infanticide • May not be enough workers to maintain the army, sustain the economy, or support retirees when their parents reach old age • Hong Kong has the lowest birth rate in the world with a fertility rate of only .9

  15. Mortality • Crude death rates- deaths per thousand persons in any given year • Natural increase- crude death rate subtracted from crude birth rate • Total growth rate- includes immigration, emigration, births, and deaths

  16. Life Span/ Life Expectancy • Life span- the oldest age to which a species is known to survive • Life expectancy- the average age that a newborn infant can expect to attain in any given society • Rose from 40 to 67 years over the past century • Declining mortality, not rising fertility is the primary cause of population growth

  17. Life Expectancy • Longer lives were due to better nutrition, improved sanitation, clean water, and education • There is a good correlation between annual income and life expectancy up to $4,000 per person • Some believe life expectancy is approaching a plateau

  18. Demographics • A population that is growing rapidly by natural increase has more young people • Countries with a stable population has the same number in each age group • Dependency ratio- the number of nonworking compared to working individuals in a population • Problem for both rapidly and slowly growing countries

  19. Emigration and Immigration • More-developed regions are expected to gain 2 million immigrants per year for the next 50 years. • Citizens of many nations argue that immigrants take a away jobs, overload social services, and ignore established rules of behavior or social values. • In some nations, geopolitical demographic policy encourages/forces internal mass migration. • Ex: Indonesia and China

  20. Population Growth: Opposing Factors • Pronatalist pressures • Children =source of pleasure, pride and comfort. • They can support their elders where there is no social security system. • They can help by providing additional income, and by doing chores. • In some regions, children give families status, and provide parents with a sense of accomplishment.

  21. Factors Discouraging Reproduction • Higher education and personal freedoms for women • Education and socioeconomic status are typically inversely related to fertility in wealthier nations. • In developing countries: the two are positively correlated, fertility is likely to increase as educational levels and socioeconomic status rise (more money = more children because children aren’t as expensive) • Ex: America’s population relative to WWII, the Great Depression, and the Baby Boom.

  22. Could we have a birth dearth? • Some nations birth rates have fallen below replacement levels. • Most European countries suffer from this deficit, with negative rates of population increase. • Negative effects of this could include: lack of soldiers, lack of works, and not enough workers and taxpayers to contribute to the social system. • Possible reasons for the decrease are: Toxins and endocrine hormone disrupters in our environment interfere with sperm production. (Phthalates in plastics)

  23. Demographic Transition

  24. Demographic Transition Cont’d… • There are four necessary conditions for demographic transition: • 1. improved standard of living • Increased confidence that children will survive to maturity • Improved social status of women • Increased availability and use of birth control • Some nations have already succeeded in controlling population

  25. Factors contributing to stabilizing populations • 1. growing prosperity and social reforms • 2. available technology • 3. less developed countries have historic patterns to follow • 4. modern communications

  26. People are still pessimistic… • Lester Brown: poorer countries are caught in a demographic trap that prevents them from escaping from the middle phase of the demographic transition. • To escape they need to reduce population growth ASAP.

  27. Social Justice & Population • Social justice is believed to be the key to successful demographic transitions. • Violence, poverty, hunger, environmental degradation and population are all results of a lack of social justice, not a lack of resources. • The relationship between rich and poor countries goes back to colonial powers vs. colonies. • Rather than the maximum number of people, we should be thinking in terms of the optimum number of people.

  28. Women’s Rights Affect Fertility • The best way to ensure a child’s survival is to ensure the rights of mothers. • Land reform, political rights, opportunities to earn her own income and improved health status of women are better indicators of total fertility and family welfare that gross national product. • High income does not always mean better welfare for kids

  29. Factors affecting fertility • High mortality rates typically lead parents to having more children to ensure that some survive • Better nutrition, improved health care, oral therapy, immunization have brought about reductions in mortality rates, which have in turn led to falling birth rates. • Saving 5 million children each year from easily preventable communicable diseases would avoid 20 or 30 million extra births.

  30. Family Planning and Fertility Control • Family planning implies that parents will control their reproductive lives • Fertility control dates back to our hunting and gathering ancestors • San Women effectively space the amount of children they have • Some older techniques of fertility control: folk medicines, abstinence, abortion, infanticide.

  31. Current family planning methods • Major methods of birth control: • 1. avoidance of sex during fertile periods • 2. mechanical barriers that prevent contact between sperm and egg • 3. surgical methods that prevent release of sperm/egg • 4. chemicals that prevent maturation of sperm or eggs or implantation of the embryo in the uterus • 5. physical barriers to implantations • 6. abortions

  32. New Developments in Family Planning • Five new birth control products approved by the FDA • 1. Ensure • 2. Mirena • 3. Lunelle • 4. NuvaRing • 5. Ortho Evra

  33. The Future of Human Populations • There are variations of where the population will land in the next century • Optimistic/low prediction: 7 billion in 2050 to <6 billion by 2150. • Medium prediction: reaches 8.9 billion in 2050 and stabilizes • Pessimistic prediction: constant growth to 25 billion by 2150

  34. Did you know…? • While many couples use family techniques, 100 million couples say they’d like to but do not have access to them?

  35. The United Nations • The U.S is becoming increasingly isolated in its population policies • 1994 Cairo, Egypt meeting to discuss women’s rights • U.S. has been withdrawing from population initiatives starting around 2000. • Didn’t reaffirm ICPD (International Conference on Population and Development) • President Bush didn’t release $34 million appropriated by Congress for UN population fund

  36. The United Nations continued… • Money denied by President Bush could have prevented 2 million unwanted pregnancies, 800,000 abortions, 4,700 maternal deaths, 60,000 cases of serious maternal illness and 77,000 + infant and child deaths. • UNFPA is the world’s largest international source of funding for population and reproductive health programs

  37. So what have we learned? Big societal changes are needed to make family planning work • Improved social, educational, and economic status form women • Improved status for children (fewer children are born) • Acceptance of calculated choice as a valid element in life in general and in fertility in particular • Social security and political stability that give people the means and the confidence to plan for the future • Knowledge, availability, and use of effective and acceptable means of birth control.