Our numbers expand, but Earth’s natural systems do not Lester R. Brown

The Human Population and its Impact Unit 8 The Human Population and its Impact

Human Population Growth Reflects change from agrarian to industrial culture Continues to grow exponentially at rate of (≈227,000 people/day) Growth is unevenly distributed across globe

3 Factors for Human Population Growth Ability to expand into almost all climate zones, habitats Ability to grow more food per unit of land Drop in death rates due to improved sanitation, medicines

Cultural Carrying Capacity Maximum number of people living comfortable and sustainably

Factors Affecting Human Population Size Births Deaths Migration Population Change = (births + immigration) – (deaths + emigration)

Demographic Quantities Crude Birth Rate (CBR) number of live births per 1000 people in a population in a given year Crude Death Rate (CDR) Number of deaths per 1000 people in a population in a given year

21 World 9 11 All developed countries 10 All developing countries 24 8 Crude Birth Rate CBR Crude Death Rate CDR 21 World 9 11 All developed countries 10 All developing countries 24 8 Developing countries (w/o China) 9 29

© 2004 Brooks/Cole – Thomson Learning Africa Latin America Asia Oceania United States North Europe 38 14 23 6 20 7 18 15 9 10 11 CBR CDR © 2004 Brooks/Cole – Thomson Learning

Demographic Quantities Zero Population Growth (ZPG) births + immigration = deaths + emigration

Rate of the World’s Annual Population Change Annual rate of population change (%) Birth Rate – Death Rate 1000 X 100 or… Birth Rate – Death rate 10

Developing vs Developed Countries China and India- 37% of global population US- 4.5% of global population Developing countries > 95% growth between 1998-2025

World Population Growth <1% 1-1.9% 2-2.9% 3+% Data not available

© 2004 Brooks/Cole – Thomson Learning China 1.28 billion 37% 1.5 billion India 1 billion 1.4 billion USA 288 million 4.6% 346 million Indonesia 217 million 282 million Brazil 174 million The worlds 10 most populous countries (2002) 219 million Pakistan 144 million © 2004 Brooks/Cole – Thomson Learning 242 million Russia 144 million 129 million Bangladesh 134 million 178 million Japan 127 million 121 million Nigeria 130 million 205 million 2002 2025

Where are they? Beijing Tibet CHINA NEPAL JAPAN Shanghai Delhi PAKISTAN INDIA Hong Kong Bhopal Calcutta PACIFIC OCEAN BANGLADESH THAILAND Bombay INDIAN OCEAN PHILIPPINES State of Kerala Bangkok SRI LANKA NEW GUINEA BORNEO INDONESIA

Global Fertility Rates 2 types: Replacement Level Fertility: number of children to replace reproductive couple -2.1 in developed countries -2.5 in developing countries -population momentum: future increase in population due to large number of people entering into childbearing years (despite those couple having few children)

Global Fertility Rates (cont’d) Total Fertility Rate (TFR): estimate of average number of children a woman will have in her lifetime -most useful measure for projecting future population growth

TFR Facts 2000: TFR= 2.9* Highest TFR: Africa= 5.3 TFR= 2.3; world population= 8 billion in 2025 *if TFR remained at 2.9, human population would reach 694 billion by 2150

There has been a decline in total fertility rates. World 5 children per women 2.8 Developed countries 2.5 1.6 © 2004 Brooks/Cole – Thomson Learning Developing countries 6.5 3.1 There has been a decline in total fertility rates. Africa 6.6 5.2 Latin America 5.9 2.7 Asia 5.9 2.6 Oceania 3.8 2.5 North America 3.5 2.1 Europe 2.6 1.4 1950 2002

Population (billions) Population Projections 12 11 High High 10.9 10 Medium Low 9 Medium 9.3 8 Population (billions) 7 6 Low 7.3 5 4 3 2 1950 1960 1970 1980 1990 2000 2010 2020 2030 2040 2050 Year

Case Study: U.S. Population 2012- 310 mil (US pop in 1900 was 79 mil; took 139 yrs to add first 100 mil; 52 yrs to add next 100 mil; 39 yrs to add 3rd 100 mil) TFR= 2.1 Has highest fertility rate and highest immigration rate of any industrialized country (rate of growth has declined, but population is still growing faster than developed countries and China)

U.S. Population Growth 1.66 million more births than deaths 800,000- 1,000,000 legal immigrants -53% from Latin America -25% from Asia -14% from Europe 300,000 illegal immigrants (est 11 million) Projected growth by 2050: 41% to 86% (Pacific NW growth is higher than India!)

Births per thousand population Birth Rates in the U.S. 32 30 28 26 Births per thousand population 24 22 20 18 Demographic transition End of World War II 16 Baby Boom Echo Baby Boom 14 Depression Baby bust 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010 Year

© 2004 Brooks/Cole – Thomson Learning United States Mexico Canada © 2004 Brooks/Cole – Thomson Learning 288 million Population (2002) 102 million 31 million Projected population (2025) 346 million 132 million 36 million Infant Mortality Rate 6.6 25 5.3 77 years Life expectancy 75 years 79 years 2.1 Total Fertility Rate (TFR) 2.9 Comparison of Basic Demographic Data 1.5 21% % population under age 15 33% 19% 13% % population over age 65 5% 13% $34,110 Per Capita GNI PPP $8,790 $27,170

Reasons for Projected U.S. Growth Large numbers of baby boom woman still in child-bearing years Increase in number of unmarried mothers High levels of immigrants Inadequate family-planning services

Factors Affecting Total Fertility Rates Importance of children in workforce (developing countries) Cost of raising and educating children (developed countries) Pension systems (reduces parents’ need for child support in their old age)

Factors Affecting Total Fertility Rates (cont’d) Urbanization (better access to family planning ) Educational, employment opportunities for women (more education-fewer children) Average age at which woman has first child Religious beliefs, traditions, and cultural norms

Factors Affecting Death Rates (also responsible for increased growth rates) Increased food supply Better nutrition Medical advances in immunizations, antibiotics Improved sanitation, cleaner water (“It’s not that people stopped breeding like rabbits, it’s just that they stopped dying like flies” UN)

Developed Countries Rate of natural increase Rate per 1,000 people 50 Rate of natural increase © 2004 Brooks/Cole – Thomson Learning 40 30 Crude Birth Rate Rate per 1,000 people 20 Crude Death Rate 10 Rate of natural increase = Crude Birth Rate –Crude Death Rate 1775 1800 1850 1900 1950 2000 2050 Year

Developing Countries Crude Birth Rate Rate of natural increase 50 Crude Birth Rate © 2004 Brooks/Cole – Thomson Learning 40 Rate of natural increase 30 Rate per 1,000 People Crude Death Rate 20 10 Rate of natural increase = Crude Birth Rate – Crude Death Rate 1775 1800 1850 1900 1950 2000 2050 Year

Indicators of Overall Health of a Country 1. Life expectancy: years a newborn infant can expect to live -77 years (developed countries) -64 years (developing countries- without AIDS, war) -globally: 48 yrs (1955), 66 yrs (1998), 73 yrs (2025) -Africa: less than 50 yrs

Indicators of Overall Health of a Country (cont’d) 2. Infant mortality rate: # of babies/1000 that die before their 1st birthday -best measure of society’s quality of life -reflects level of nutrition (undernutrition, malnutrition), health care (4 million infants die each year of preventable causes)

Infant Mortality Rates in 2002 Infant deaths per 1,000 live births <10 10-35 36-70 71-100 100+ Data not available Infant Mortality Rates in 2002

Reasons for U.S. Infant Mortality Inadequate health care for poor women Drug addiction among pregnant women High birth rate among teenage women -US has highest teenage pregnancy rate in world -babies born to teenagers is low (most important factor in infant deaths)

Population Age Structure Age structure diagrams: proportion of the population at each age level 3 main age categories: -prereproductive: 0-14 -reproductive: 15-44 -postreproductive: 45+ Age distribution has long-lasting economic and social impacts

Population Age Structure Rapid Growth Guatemala Nigeria Saudi Arabia Slow Growth United States Australia Canada Male Female Zero Growth Spain Austria Greece Negative Growth Germany Bulgaria Sweden

How Does Age Structure Affect Population Growth? Rapid growth: wide base of preproductive age (0-14) 2010: 27% of global population was under 15 (1 in 4 on planet) -30% in developing countries -16% in developed countries -44% in Africa

Case Study: American Baby Boom/Bust 1946-1964: 79 million people were added to U.S.: -dominated demand for goods, services -decides who is elected to office -decides what laws are passed -seniors (65 ↑) fastest growing age group (“Graying of America”) -will pass on higher unemployment, taxes to millennial generation (born since 1980 AKA you guys)

Number of Workers Supporting each Social Security Beneficiary 1945 41.9 workers 40 To maintain current ratio of workers to retirees, US will need to absorb 10.8 immigrants each year through 2050 30 20 Number of Workers Supporting each Social Security Beneficiary 1950 16.5 10 2075 1.9 1945 2000 2050 2075 Year

Population Decline Gradual decline: negative effects are manageable Rapid decline: -threaten economic growth -labor shortages (health-care workers) -budget strains on pension plans, health- care costs ex. Japan, Russia, Germany, Italy, Greece, Portugal

40 35 30 25 20 15 10 5 1950 1970 1990 2010 2030 2050 2070 2090 2110 2130 2150 Year Age Distribution (%) Global Aging Rapid population decline can lead to severe economic and social problems. Under age 15 Age 60 or over Age 80 or over

Case Study: The Graying of Japan 1949: TFR of 4.5 1998: TFR of 1.4 -resists increased immigration (fear of social cohesiveness) -must depend on automation and women working outside of home

Population Decline and AIDS 1981-2009: 27 million people died of AIDS/ 2 million every year (WHO) -22,000 in US; 39,000 in China; 350,000 Africa -results in loss of productive workers -drastically alters age structure -creates large number of orphans

The Environment and Population 1995: 27 million international refugees moved due to environment degradation (drought, desertification, deforestation, soil erosion, resource shortages) 1988-1998: 50 million left homeless due to natural disasters (earthquakes, hurricanes, floods, landslides) US, Australia, Canada accept large #’s of refugees

Why Slow Population Growth?: Opposing Views Asking the wrong question What is the earth’s optimum sustainable population? Earth is not over-populated. Longer life span today proof of capability to sustain greater population Population regulation is a violation of personal freedom Should be able to have as many children as we want. Cannot provide basic necessities for everyone today Raising the death rates for humans Increasing environmental harm

FYI: For Your Consideration Some computer models suggest that the Earth could support 20-48 billion people if everyone existed at a survival level: -grain-only diet -cultivate all arable land -mine the Earth’s crust to a depth of a mile Some scientists suggest that the key factor isn’t overpopulation, but overconsumption: affluence leading to over-consumption of resources per person

How to Slow Population Growth Reduce poverty by promoting economic development Elevate the status of women Encourage family planning

Economic Development Occurs in Stages Demographic transition: hypothesis of population change as countries become more industrialized: 1) death rates drop 2) birth rates decline

Demographic Transition Pre-industrial stage: harsh living conditions, high infant mortality and death rates; population growth is small (if at all) Transitional stage: start of industrialization, ↑ food production, ↓ death rate; pop. growth is rapid- China, India 3. Industrialized stage: birth rates↓, ↑ access to birth control, reduced infant mortality, higher cost of raising children; pop. growth slows 4. Post-industrial: further decline in birth rate, ZPG -37 countries, including western Europe, Japan

Relative population size Birth rate and death rate Stage 1 Preindustrial Stage 2 Transitional Stage 3 Industrial Stage 4 Postindustrial Low High Relative population size (number per 1,000 per year) Birth rate and death rate 80 70 60 50 40 30 20 10 Birth rate Death rate Total population Low growth rate Increasing growth rate Very high growth rate Decreasing growth rate Low growth rate Zero growth rate Negative growth rate Time

Demographic Transition (cont’d) Developing countries: transitional stage -pop growth outstrips economic growth (demographic trap) -lack skilled workers to produce high-tech products -lack capital, resources for economic development

Elevating the Status of Women Females make up ½ of global pop, but have fewer opportunities for education (economic opportunities) Females do most of the world’s domestic work (growing food, hauling wood and water), child care, and health care (unpaid) Benefits of educating females: -ability to control fertility (tend to have fewer children) -earn an income -societies that do not suppress women

Typical Workday for a Woman in Africa 4:45 A.M. Wake, wash, and eat 5:00 A.M.- 5:30 A.M. Walk to fields 5:30 AM.- 3:00 P.M. Work in fields 3:00 P.M.- 4:00 P.M. Collect firewood 4:00 P.M.- 5:30 P.M. Pound and grind corn 5:30 P.M.- 6:30 P.M. Collect water 6:30 P.M.- 8:30 P.M. Cook for family and eat 8:30 P.M.- 9:30 P.M. Wash dishes and children 9:30 P.M. Go to bed

Promoting Family Planning Major factor in reducing birth rate Reduced # of abortions Reduced # mother and fetus deaths (600,000 women die from pregnancy-related causes) Drop in TFR by ≈ 55% in developing countries (6 in 1960 to 3.2 in 2000) Financial benefit: each dollar spent in developing countries saves $10-$16 in social services

Use of Rewards and Penalties in Reducing Births Penalties (China): higher taxes, eliminating tax deductions for third child, loss of health benefits and food allotments Rewards: reinforcement of trends toward smaller families (social acceptance), increasing a poor family’s economic status

India’s Failed Family Planning Program Bureaucratic inefficiency. Low status of women. Extreme poverty. Lack of administrative financial support. Disagreement over the best ways to slow population growth.

China’s Family Planning Program Currently, China’s TFR is 1.6 children per women. China has moved 300 million people out of poverty. Problems: -Strong male preference leads to gender imbalance (by 2030, 30 million males will not be able to find brides) -Average population age is increasing without children to support elders

The Rule of 70 Used to estimate doubling time of any population growing exponentially Formula: Doubling time (yrs) = 70 % growth rate

Rule of 70 Example in 2010, the population of Upper Fremont is 200,000 and growing at a rate of 2% each year. (a) If the rate of growth remains constant, calculate the population in 2045 -doubling time = 70 = 35 yrs 2 -2045-2010 = 35 yrs - answer: 400,000 What will the population be in 2080?

Chapter 6, 22 Human Population Exam Focus 3 factors for exponential pop growth Definition of cultural carrying capacity 3 main factors affecting pop. Size (know the equation) ZPG (what it stands for and know the equation) TFR (what it stands for and what it means) CBR; CDR (know formula) Replacement Level Fertility 4 stages of demographic transition Most useful indicators of overall health of a population

Human Population Exam Focus Population momentum Relative growth rates of developed vs developing countries Cases of India and China (why hasn’t India’s family planning been successful?; results of China’s population control) Reasons for infant mortality in US Predicted outcome of “Boomer” generation reaching 65 Age structure graphs and examples of each Ways to slow population growth Key factors that women to have fewer children Family planning Affect of AIDS on global population