Objective and Warmup: 11/8/10 Objective: SWBAT Evaluate the different methods of taking a population census. Warmup: Provide ways ecologists measure populations.

Human Populations

History of Human Population Early Hunter Gatherers Nomadic, With a Strong Sense of the Earth Practiced Intentional Birth Control Rise of Agriculture Necessary for Survival Animals became extinct via predation and altered habitat Humans began to cultivate own food

History of Human Population Cont… Agriculture Gives Rise to Cities Food Produced in Country, Consumed in City Food wastes are no longer returned to soil Soil becomes less productive Waste of Populations Concentrated in Cities Population Control in Medieval Societies Disease Famine Wars

History of Human Population Cont.. Industrialization View of Children During Early Phases of Industrial Growth Valued as cheap source of income and cheap labor Exponential growth of populations By 1900s, Birth Rate in Industrialized World Dropped Rise in standards of living Safe and inexpensive means of birth control introduced Increase in the cost of child rearing

Human Population Growth

Current World Population Global population on November 2, 2009 at 7:23 am U.S. 307,841,263 World 6,794,428,411 The global population grows by: Nearly 2.3 persons per seconds Nearly 8,343 persons per hour Over 200,234 persons per day Over 73 million persons per year

1 billion-s = 11,574 days = 31.7 years How Much is a Billion? 1,000 seconds = 16.7 minutes 1 million-s = 16,677 min = 11.6 days 1 billion-s = 11,574 days = 31.7 years 1,000 pennies = ~ 88 ounces = 5.5 pounds 1 million pennies = 5,500 pounds (~1-Suburban) 1 billion pennies = 2,750 tons (~2 Space Shuttles)

Objectives and Warmup: 11/9/10 Objectives: SWBAT Apply the rule of doubling time to the provided scenarios. Warmup: If the current rate of human population growth continues, the number of people on Earth will double in the next 50 years. Will this rapid growth actually occur?

Rate of Global Population Change use: International Data Base http://www.census.gov/ipc/www/idbnew.html, CBR (crude birth rate) = # births / 1000 population 1990: 24 now: 20.6 CDR (crude death rate) = # deaths / 1000 population 1990: 9 now: 8.8 Growth Rate = (b + i) – (d + e) 1990: 1.5% now: 1.19% growth rates have come down

Crude Birth Rates

Crude Death Rates

Doubling Time Doubling Time of a population: 70/annual percentage growth rate. Doubling time for the Human Population 800 million in 1700 1.6 billion in 1900 3.2 billion in 1965 6.1 billion in 2000 In 2000, each second 4-5 children born, 2 people died J shaped curve

Women could have 15 children in their lifetime Women could have 15 children in their lifetime. Yet across the world, they only have 2 ½ children on average. Why is that? Which factors influence the number of children born to each woman, and what effects do they have?

Objectives and Warmup 11/11/10 Objective: SWBAT Analyze the factors that affect birth and death rates between developing and developed countries. Warmup: If a population of 100,000 has 2,700 births per year and 900 deaths per year, what is its growth rate in percent per year? Calculate the doubling time for a population with a 1.3% growth rate.

LIMITS TO GROWTH Thomas Malthus-excess population growth is the cause of many social and environmental problems Disease, famine and population control is only way to stabilize Karl Marx- oppression and exploitation are the real causes of poverty and environmental degradation Population growth is a symptom or result of other problems, not the source Slow population growth through social justice.

HUMAN DEMOGRAPHY Demography - vital statistics about people such as births, deaths, where they live, and population size. 2 demographic worlds First is poor, young, and rapidly growing. Less-developed countries contain 80% of world population, and will account for 90% of projected growth. Second is wealthy, old, and mostly shrinking. Western Europe, Japan.

Human Population Density

Factors affecting birth rates and fertility rates Age of woman at time of marriage Availability and affordability of birth control and abortion Children needed in the workforce Costs of raising and educating children Culture, religion, tradition Government programs Infant mortality

Factors affecting death rates Availability and affordability of health care, food and better nutrition Safer water supplies Improvements in sanitation and pollution control Improvements in medical and public health

Indicators of overall health of people in a country Life expectancy-average number of years a newborn infant can expect to live Infant mortality rate-number of babies out of every 1000 born who die before age 1

Objectives and Warmup: 11/12/10 Analyze factors that affect population size. Warmup: Why are life expectancies and infant mortality rates in highly developed and developing countries so different?

Human Population Dynamics 3 sources of change in population size — Migration Fertility Mortality

Migration-Influencing Population Size Most countries restrict immigration Canada, Australia, U.S. - most immigration ~1% of developing nations pop. Emigrates Migration from rural to urban areas

Family Planning Reduce births and abortions reduces children's social services needs reduces risk of childbearing deaths Effectiveness depends on program design and funding: good in some countries with good program poor in other countries

Rewards and Penalties to Reduce Births What might work: Encourage people to have fewer children Reinforce existing customs and trends toward smaller families Don’t penalize for already existing larger families Increase poor family’s economic status

Disappointing results due to: poor planning bureaucratic inefficiency Case Study-India Family planning efforts began in 1952; fertility rate declined from 5.3 to 3.4 but population grow is still exponential Disappointing results due to: poor planning bureaucratic inefficiency low status of women extreme poverty lack of administrative & financial support

Curbing Population Growth Provide economic incentives for having less children Empower and educate women Access to education and paying jobs outside home Society doesn’t suppress women’s rights Government family planning services Reduce poverty and economic development

Case Study-China Family planning efforts began in 1970 Population control program is extensive, intrusive and strict: postpone childbearing only one child/family -->benefits Free education and health care Increased personal and family incomes Preferential housing and retirement income effective because China is dictatorship; limited resources would have mean disaster

Objectives and Warmup Objectives: Analyze age structure distributions to determine the difference between developing and developed countries. Warmup: In 2050, there will be approximately 9 billion people in the world, according to the most widely accepted estimate. What problems might this create for developing countries? What challenges will industrialized nations face?

Bar graph that shows the age and gender composition of a region Age Structure Bar graph that shows the age and gender composition of a region horizontal axis: gender male: left-hand female: right-hand absolute number of people or % vertical axis: age 5-year or 10-year age groups

Age Structure

Objectives and Warmup: 11/16/10 Analyze age structure distributions to determine if the country is considered to be developed or developing. Analyze age structure distributions to determine the future population of a specified country. Warmup: Describe at least three factors that determine whether a nation is classified as a developed or developing country.

Developed vs. Developing… standard of living •     literacy rate •     birth rate •     death rate, esp. infant mortality rate •     per capita GDP •     degree of urbanization •     life expectancy •     health care system •     educational system, esp. opportunities for women •     amount of infrastructure •     global vs local market economy •     use of technology

Objectives and Warmup: 11/17/10 Analyze the demographic transition model using classroom data Warmup: Compare the reproductive rights of women in a highly developed nation (other than the USA) with their counterparts in one of the least developed nations.

4 Stages of the Demographic Transition Birth rates, death rates and growth rates change through time as societies change: modernize, urbanize gain access to technology

Stage 1: Pre-Industrial High birth rates, high (at time erratic) death rates, low growth rates Stage for much of human history, traditional societies Living conditions severe

Stage 2: Transitional High birth rates, declining death rates, rising growth rates Improvements in sanitation (water) and medicine Ex. Europe at the start of Industrial Revolution developing countries since the 50s/60s much of Africa today, some countries of Asia (Afghanistan, Nepal, etc.)

Stage 3: Industrial Continued decline of death rates, declining birth rates, growth rates decline from high to lower levels Lower death rate, in particular infant mortality rates Economic change: urbanization (incentive to have fewer children) Better jobs Education for women Mexico today

Stage 4 Post-Industrial Stage 4: birth rates are less than mortality rates Zero population growth or declining population growth Standard of living is high Ex. Japan, many European countries