Chapter 4 Human Populations

1. Chapter 4 Human Populations

2. Chapter Four - Topics • Population growth • Limits to growth: some opposing views • Human demography • Population growth: opposing factors • Demographic transition • Family planning and fertility control • The future of human populations

3. Part 1: Population Growth World population now 6.47 billion (Oct 12, 2005) Click here for current US and World population estimates -> http://www.census.gov/main/www/popclock.html

4. Current Birth and Death Rates • Every second: about 4 children are born, while about 2 other people die • Net gain: 2.3 humans added to the world population every second, 72 million added every year

5. Human Population Levels Throughout History ADD FIG. 4.2

6. ADD TABLE 4.1

7. Part 2: Limits to Growth Varying Perspectives • Overpopulation causes resource depletion and environmental degradation • Human ingenuity and technology will allow us to overcome any problems - more people may be beneficial • Resources are sufficient to meet everyone's needs - shortages are the result of greed, waste, and oppression

8. Decisions on how many children to have are influenced by many factors, including culture, religion, politics, need for old-age security, and immediate family finances.

9. Part 3: Human Demography • Demography - vital statistics about people, such as births and deaths • Two demographic worlds • Less-developed counties represent 80% of the world population, but more than 90% of projected growth • Richer countries tend to have negative growth rates What a stupid term…click below for definition of "third", "second", and "first" worlds… http://www.thirdworldtraveler.com/Third_World/TW_definition_description.html

11. By 2050, India will probably be the world's most populous country. (297)

12. Fertility and Birth Rates • Fecundity - physical ability to reproduce • Fertility - the actual production of offspring • Crude birth rate - number of births per year per thousand people • Total fertility rate - number of children born to an average woman during her reproductive life • Zero population growth (ZPG) - occurs when births + immigration just equal deaths + emigration

13. Regional Declines in Total Fertility Rates

14. China's one-child- per-family policy decreased the country's fertility rate from 6 to 1.8 in two decades. However, the policy is very controversial.

16. As incomes rise, so does life expectancy.

17. Living Longer: Demographic Implications • A population growing by natural increase has more young people than does a stationary population. • Dependency ratio - the number of nonworking individuals compared to working individuals - declining in countries such as the U.S. and Japan • If current trends continue, by 2100 the median age in the U.S. will be 60.

19. Part 4: Population Growth -Opposing Factors Pronatalist pressures • Factors that increase people's desires to have children Birth reduction pressures • Factors that tend to reduce fertility

20. U.S. Birth Rates: 1910-2001

21. Part 5: Demographic Transition • Optimistic view - world population will stabilize during this century • Pessimistic view - poorer countries of the world are caught in a "demographic trap" - helping poor countries will only further threaten the earth's resources • Social justice view - overpopulation due to a lack of justice, not resources

22. Demographic Transition Accompanying Economic and Social Development

23. Fig. 4.13

24. Infant Mortality and Women's Rights

25. Part 7: The Future of Human Populations