1. Population and Society

2. 4 Major Causes of Environmental Change
Population change
Institutions
Attitudes, values, belief systems
Technological change

3. Carrying Capacity
The maximum number of organisms an environment can support.
But highly dependent on technology, there is no set carrying capacity, technology increases production
Fruit flies in a petri dish (resource base is a banana)
Eventually, the population will level off and decline as soon as the resource base is used up
Angel Island in San Francisco Bay: plagued wiith too mnay deer (few organisms brought in early 1900’s without predator control
Scrawny, underfed animals growing in population in a degrading environment, trampled soil, trees stripped of bark, etc…
State game managers propose hunting –how cruel, responded the public. Like the elk of Yellowstone. No one wanted to see the national symbol hunted.
Ok, import coyotes. But Society for the Prevention of Cruelty to animals opposed.
Relocation animals relocated, many died within the first few months. Net cost (1982) $2, state refused to refinance. No one else wanted to foot the bill.
Ethical questions raised. Moral questions about the animals.
carrying capacity for humans and lifeboat ethics.
Ethical questions are raised.

4. Thomas Malthus (1766-1834) An Essay on Population (1798).
Wrote at beginning of the 19th century, when population growth and industry were raising demands for food faster than English agriculture could respond.
Human population would always increase exponentially (the larger it gets the faster it grows) while the supply of food and land would only increase “arithmetically” (additively)
Discuss each as Malthus did not foresee:
Acres of farmland increased
Intensification of resources/alternative resources
New sectors of the economy opened up -> information age
Very simplistic and linear way of correlating the relationship between population growth and resource expansion. Glosses over complex realities such as the wealth gap and distribution of wealth
Positive checks: war, disease, chaos…humans cannot be compared to the fruitflies. Very simplistic argument!

5. Scarce farmland
Overuse of resources
Poverty and human misery
Each increase in food supply only meant that more people could live in poverty

6. Cultural Carrying Capacity
“There should be no more people in a country than could enjoy a daily glass of wine and a piece of beef for dinner.” --Thomas Malthus
Cultural carrying capacity is smaller
than simple carrying capacity.
The cultural carrying capacity supports the population + the luxuries: street lighting, vacations, private cars, air conditioning etc…

7. World Population Growth Rates
Population growth rates measured by annual increase in a country’s population are highest in
Africa and Middle East. Growth rates are flat in U.S., Europe, and former Soviet Union

8. World Population Growth Doubling Time
billion
billion
1960 (30 years) 3 billion
1974 (14 years) 4 billion
1986 (12 years) 5 billion
1999 (13 years) 6 billion
60,000 years for population to reach 1 billion
150 years to increase by 5 billion!

9. The current increase of the Earth’s human population in either absolute or relative terms, vastly exceeds the average increases over most of human history.
Nobody saw this coming.
In demographers predicted that the world population billion people by the end of the 21st century (we hit that by 1955).
1950 estimate 3.3 billion by 2000 (off by 50%.)

10. World Population Growth
Growth rate was at all time peak of 2.1% between (The Population Bomb by Paul Ehrlich, 1968).
Predicted "in the 1970s and 1980s and 1980 hundreds of millions of people will starve to death", that nothing can be done to avoid mass famine greater than any in the history, and radical action is needed to limit the overpopulation. ( a neo-Malthusian position)
The growth rate has since declined to about 1.2% per year.
Show projected rates for future, conservative and less conservative figure(overhead). Talk about underestimation of population growth in the past. (off by 50%) because they did not take into account decline in death rates and improved qualtiy of life.

11. Global fertility rates are falling: from 5 children per woman per lifetime in to 2.7 children in
Absolute annual increase in population peaked around 1990 at 86 million and has fallen to 77 million.
In 1960, five countries had total fertility rates at or below the required level required to replace the population in the long run.
By 2000 there were 64 such countries with 44% of world population

12. Beginning-High Birth rates, high death rates
The Demographic Transition Model
Beginning-High Birth rates, high death rates
Transition-High birth rates, low death rates (By 1900, life expectancy at birth was years, today it is 78 years for women and 71 for men and rising rapidly).
Third Stage-low death rates, low birth rates

13. Why has the world’s population increased by so much?
The Demographic Transition Model
People didn’t start having more babies, more people began to survive.
p. 183 and overhead:
Beginning: high birth, high death
Transition: high births, low deaths (population bomb or explosion)
3rd stage: low birth, low death

14. Demographic Transition Continued What makes the death rate decrease?
Increased productivity: agriculture can support larger populations than before
Advances in the control of epidemic diseases and improvement in public health, death control: antibiotics, biocide DDT to control insect vectors of infection, vaccines against smallpox, measles, whooping cough, and drugs that cured tuberculosis and malaria
More informaiton about birth contol combined with increased/improved status of women have been factors in birth declines in all countries.

15. Demographic Transition Continued What makes the birth rate decrease?
As people become urbanized children go from being an economic asset, to becoming an economic burden
Cultural norms that encouraged a women to have large numbers of children weakened.
Increasing opportunities for women: low status of women=economic dependence and higher birthrates.

16. The Six Commandments of Population Control
1. Promote Contraceptives.
2. Develop Economies
3. Save Children
4. Empower and Educate Women
5. Educate Men
6. Do all of the above

17. The Population Debate
Neo-Malthusian: our capacity to produce food cannot keep up with our reproductive capacity.
Population growth is a severe threat
There are limits to the physical capacity of the planet to sustain growth
Population growth is also a major cause of environmental degradation

18. Explaining World Hunger
Agricultural modernization perspective argues that the world hunger problem is caused by not enough food produced by traditional agriculture
Another major factor lies not in the quantity of food, but the distribution of food.
Cycles and feedback loops with transformation of agriculture from traditional to modern

19. Where is most population growth in the US from?
According to the census bureau, post-1970 immigrants and their descendents will account for over 80% of US population growth between now and mid 21st century.

20. Migration: Population Growth in the US
1994: US Commission on Immigration Reform declared: “We disagree with those who would label efforts to control immigration as being inherently anti-immigrant. Rather it is both a right and a responsibility of a democratic society to manage immigration so it serves national interest.”

21. Population growth in the US
According to surveys by the Wall Street Journal and the Latino National Political Survey: Clear majorities of African Americans and Latinos favor reductions in legal and illegal immigration.

22. The Politics of Population
1974: The First UN Conference on Population
Developing countries rejected the Neo-Malthusian position, that poor countries are poor because of overpopulation.
Instead, poverty causes overpopulation.
Redistribution of wealth is needed.
Birth control vs. wealth control

23. Today, many developing countries are actively trying to limit population.
China’s one child policy

24. Today’s World Population
World POPClock Projection
According to the International Programs Center, U.S. Bureau of the Census,

25. Will Malthus always be wrong
Will Malthus always be wrong? Current Declines in World Population Growth Rate

26. How Big will the Population Get? Trends
The global total fertility rate fell from 5 children per woman per lifetime in to 2.7 children in
Absolute annual increase in population peaked around 1990 at 86 million, and more recently is at 77 million
64 countries with 44% of total population now have fertility rates below those needed to replace population

27. More Trends
More than half of the annual increase currently occurs in six countries: India, China, Pakistan, Bangladesh, Nigeria, and the US (but US only 4%).

29. Population Growth Scenarios
Fertility at current levels= 12.8 billion by 2050.
Medium projection-8.9 billion by 2050 assumes family planning efforts will continue and suceed, fertility continues to drop..
Most optimistic prediction7.066 billion

30. More than half of annual increase in six countries: India, China, Pakistan, Bangladesh, Nigeria, and the US (mostly from immigration)

31. Will Food Production Keep Up? Will Malthus always be Wrong?