Chapter 10 Applying Population Ecology: The Human Population and Its Impact 2009 2010 U.S. 308,421,351 310,948,175 World 6,794,314,166 6,888,995,047 http://www.census.gov/main/www/popclock.html

A father complained that his son’s allowance of $10 per week was too much. The son replied, “Okay, Dad. How about this? You give me a penny for the first day of the month, 2 cents for the second, 4 cents for the next, 8 cents for the next, and so on for every day of the month.” The father readily consented. Who was more clever? What will the son’s allowance be on day 31?

$.01 $.02 $.04 $.08 $.16 $.32 $.64 $1.28 $2.56 $5.12 $10.24 $20.48 $40.96 $81.92 $163.84 $327.68 $655.36 $1310.72 $2621 $5242 $10485 $20971 $41943 $83886 $167772 $335544 $671088 $1342177 $2684354 $5368709 $10737418

Core Case Study: Is the World Overpopulated? The world’s population is projected to increase from 6.6 billion to 8.9 billion between 2006 and 2050. The debate over interactions among population growth, economic growth, politics, and moral beliefs is one of the most important and controversial issues in environmental science.

Core Case Study: Is the World Overpopulated? Much of the world’s population growth occurs in developing countries like China and India. Figure 9-1

Core Case Study: Is the World Overpopulated? Some argue that the planet has too many people. Some feel that the world can support billions of more people due to technological advances. There is a constant debate over the need to reduce population growth. Must consider moral, religious, and personal freedom.

HUMAN POPULATION GROWTH: A BRIEF HISTORY The human population has grown rapidly because of the expansion of agriculture and industrial production and lower death rates from improvements in hygiene and medicine. In 2006, the population of developed countries grew exponentially at 0.1% per year. Developing countries grew (15 times faster at 1.5% per year.

Where Are We Headed? We do not know how long we can continue increasing the earth’s carrying capacity for humans. There are likely to be between 7.2-10.6 billion people on earth by 2050. What is the optimum sustainable population of the earth based on the cultural carrying capacity?

Where Are We Headed? U.N. world population projection based on women having an average of 2.5 (high), 2.0 (medium), or 1.5 (low) children. Figure 9-2

FACTORS AFFECTING HUMAN POPULATION SIZE What is demography? The study of size, distribution, and composition of human populations and the causes and consequences of changes in these characteristics. What rates increase a population? natality/births and immigration What rates decrease a population? mortality/deaths and emmigration Instead of using raw numbers, crude birth rates and crude death rates are used (based on total number of births or deaths per 1,000 people in a population).

FACTORS AFFECTING HUMAN POPULATION SIZE Average crude death and birth rates for various groupings of countries in 2006. Figure 9-3

FACTORS AFFECTING HUMAN POPULATION SIZE The world’s 10 most populous countries in 2006 with projections in 2025. Figure 9-4

Declining Fertility Rates: Fewer Babies per Women The average number of children that a woman bears has dropped sharply. This decline is not low enough to stabilize the world’s population in the near future. Replacement-level fertility: the number of children a couple must bear to replace themselves. Total fertility rate (TFR): the average number of children a woman has during her reproductive years.

Declining Fertility Rates: Fewer Babies per Women The replacement level to sustain a population is 2.0 children. In 2006, the average global Total Fertility Rate was 2.7 children per woman. 1.6 in developed countries (down from 2.5 in 1950). 3.0 in developing countries (down from 6.5 in 1950). The world’s population has more than doubled in the last 50 years.

What factors influence birth and fertility rates? What factors have caused a decline in death rates? What is life expectancy? Average number of years a newborn can expect to live. What is infant mortality? Number of babies out of every 1000 born who will die before their first birthday

Factors Affecting Birth Rates and Fertility Rates The number of children women have is affected by: The cost of raising and educating them. Availability of pensions. Urbanization. Education and employment opportunities. Infant deaths. Marriage age. Availability of contraception and abortion.

Factors Affecting Death Rates Death rates have declined because of: Increased food supplies, better nutrition. Advances in medicine. Improved sanitation and personal hygiene. Safer water supplies. U.S. infant mortality is higher than it could be (ranked 46th world-wide) due to: Inadequate pre- and post-natal care for poor. Drug addiction. High teenage birth rate.

Case Study: Fertility and Birth Rates in the United States Nearly 2.9 million people were added to the U.S. in 2006: 59% occurred because of births outnumbering deaths. 41% came from illegal and legal immigration.

Which countries contain the majority of the world’s population growth? 97% in developing countries growth rate almost 15times faster: India, China, Pakistan, Nigeria, Bangladesh, and Indonesia What is the rule of 70? 70/ % growth rate=doubling time in years US doubling time= 70/1 China doubling time=70/.7 http://www.census.gov/ipc/www/idb/informationGateway.php Figure 9-5

Case Study: Fertility and Birth Rates in the United States The baby bust that followed the baby boom was largely due to delayed marriage, contraception, and abortion. Figure 9-6

Hourly manufacturing job wage (adjusted for inflation) $3 2000 $15 47 years Life expectancy 77 years 8% Married women working outside the home 81% 15% High school graduates 83% 10% Homes with flush toilets 98% Homes with electricity 2% 99% Living in suburbs 10% Figure 9.7 Some major changes that took place in the United States between 1900 and 2000. QUESTION: Which two of these changes do you think were the most important? (Data from U.S. Census Bureau and Department of Commerce) 52% 1900 Hourly manufacturing job wage (adjusted for inflation) $3 2000 $15 Homicides per 100,000 people 1.2 5.8 Fig. 9-7, p. 176

Case Study: U.S. Immigration Since 1820, the U.S. has admitted almost twice as many immigrants and refugees as all other countries combined. Figure 9-8

The human population is approximately 150 million 650 million 1.5 billion 6.5 billion 10 billion

Which of the following is not one of the world’s top five most populous nations? Russia United States Indonesia Brazil India

The country of Sudan has an estimated annual growth rate of 2. 5% The country of Sudan has an estimated annual growth rate of 2.5%. At this rate of growth, approximately how many years will it take for the population of Sudan to double? 22 28 35 42 50

Of the phenomena that correlate with the data above, the one that is the most direct consequence of the trend of air travel is The increase in the spread of infectious disease The increase in urban sprawl The decrease in biodiversity The increase in hypoxic aquatic ecosystems The decrease in the total fertility rate of developed nations

The richest 1/5 of the world’s population possess approximately ___ times the income of the poorest 1/5, and the richest 1/5 use 86% of the world’s resources. 10 20 40 60 80

POPULATION AGE STRUCTURE The number of people in young, middle, and older age groups determines how fast populations grow or decline. The number of people younger than age 15 is the major factor determining a country’s population growth. Changes in the distribution of a country’s age groups have long-lasting economic and social impacts.

POPULATION AGE STRUCTURE Populations with a large proportion of its people in the preproductive ages 1-14 have a large potential for rapid population growth. Figure 9-9

POPULATION AGE STRUCTURE 32% of the people in developing countries were under 15 years old in 2006 versus only 17% in developed countries. Figure 9-10

POPULATION AGE STRUCTURE Today, baby boomers make up nearly half of all adult Americans and dominate the populations demand for goods and services. Figure 9-11

Age structure diagrams http://www.census.gov/ipc/www/idb/pyramids.html

POPULATION AGE STRUCTURE About 14% of the world’s population live in countries with stabilizing or declining populations. Rapid population decline can lead to long-lasting economic and social problems. Death from AIDS can disrupt a country’s social and economic structure by removing significant numbers of young adults. Global again may help promote peace.

POPULATION AGE STRUCTURE Age structure predictions based on a medium fertility projection. The cost of an aging population will strain the global economy. Figure 9-12

POPULATION AGE STRUCTURE Some problems with rapid population decline. Which of these problems do you believe are the most important? Figure 9-13

SOLUTIONS: INFLUENCING POPULATION SIZE Demographic Transition: As countries become economically developed, their birth and death rates tend to decline. Preindustrial stage: little population growth due to high infant mortality. Transitional stage: industrialization begins, death rates drops and birth rates remain high. Industrial stage: birth rate drops and approaches death rate.

SOLUTIONS: INFLUENCING POPULATION SIZE Family planning has been a major factor in reducing the number of births and abortions throughout most of the world. Women tend to have fewer children if they are: Educated. Hold a paying job outside the home. Do not have their human right suppressed.

SOLUTIONS: INFLUENCING POPULATION SIZE The best way to slow population growth is a combination of: Investing in family planning. Reducing poverty. Elevating the status of women.

SLOWING POPULATION GROWTH IN INDIA AND CHINA For more than five decades, India has tried to control its population growth with only modest success. Since 1970, China has used a government-enforced program to cut its birth rate in half and sharply reduce its fertility rate.

Illiteracy (% of adults) 47% 17% 36% Population under age 15 (%) 20% Percentage of world population 17% India 20% China 1.1 billion Population 1.3 billion Population (2050) (estimated) 1.4 billion 1.6 billion Illiteracy (% of adults) 47% 17% 36% Population under age 15 (%) 20% 1.6% Population growth rate (%) 0.6% 2.9 children per women (down from 5.3 in 1970) Total fertility rate 1.6 children per women (down from 5.7 in 1972) 58 Infant mortality rate 27 Figure 9.15 Global connection: basic demographic data for India and China in 2006. (Data from United Nations and Population Reference Bureau) 62 years Life expectancy 70 years Percentage living below $2 per day 80 47 $3,120 GDP PPP per capita $5,890 Fig. 9-15, p. 186

India’s Failed Family Planning Program Poor planning. 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. Average population age is increasing. Not enough resource to support population.

HUMAN ASPECTS ON NATURAL SYSTEMS Excluding Antarctica, human activities have affect about 83% of the earths land surface. Figure 9-16

HUMAN ASPECTS ON NATURAL SYSTEMS We have used technology to alter much of the rest of nature in ways that threaten the survival of many other species and could reduce the quality of life for our own species. Figure 9-17

1798 Thomas Malthus wrote Principal of Population Said population grows exponentially, but food increases are linear Twice as much land would need to be farmed Recommended not feeding poor of Great Britain Charles Darwin used his idea to develop theory that competition and survival of the fittest

The country with the highest population density is Australia Population millions Total Land area (million km2) Total annual electricity use Australia 144 0.14 1.6 Great Britain 19.7 8.2 22 China 1,295 9.6 150 Sudan 70 1.12 0.20 India 1,000 3.29 60 U. S. 300 9.63 400 The country with the highest population density is Australia Great Britain China Sudan India United States

Country Population millions Total Land area (million km2) Total annual electricity use Australia 144 0.14 1.6 Great Britain 19.7 8.2 22 China 1,295 9.6 150 Sudan 70 1.12 0.20 India 1,000 3.29 60 U. S. 300 9.63 400 The country with a population approximately three times that of the U. S. is Australia Great Britain China Sudan India United States

The annual global growth rate of the human population peaked in the ____ and has been declining ever since. Early 1990s 1950s 1960s Late 1990s Early 2000s

A country with ____ is not expected to grow quickly in the near future. A pyramid-shaped age-structure diagram High female literacy A female to male ratio 1.2 to 1 Growing industrialization Many developing regions

America’s age structure diagram ____ Looks like a pyramid Reflects unequal distribution of males and females at most age groups Reflects a baby boom” in the early 1980s Reflects an aging population Reflects a population with a high growth rate

Which of the following is a true statement about the total fertility of a society? The total fertility of a society is the difference between the crude birth rate and the crude death rate The total fertility of a society is the number of children necessary for a couple to replace themselves in the next generation The total fertility of a society is negatively correlated with the average education of women The total fertility of a society is positively correlated with the number of women of child-bearing age The total fertility of a society decreases as the society progresses through the demographic transition

If a population roughly doubles in the course of 50 years, its growth rate would be close to ____% 1.5 2.5 5 20 25

As a country goes through the demographic transition, the greatest rate of population growth takes place during which phase? The preindustrial The pretransitional The transitional The industrial The post industrial

Two useful indicators of overall health in a country or region are Birth rate and death rate Replacement level fertility rate and total fertility rate Life expectancy and infant mortality rate Life expectancy and death rate Population growth rate and Birth rate

Which of the following is the best description of a population that has a stable age distribution? A large population that is growing at a constant rate A large population with a negative growth rate A population that is in the early stages of logistic population growth A growing population in which the proportions of individuals in the different age classes remain constant A small population that has not yet achieved exponential growth

It has recently been estimated that the growth in world population has slowed in the past decade. Despite this trend, environmentalists remain concerned about the environmental impact of world population, primarily because The standard of living is increasing in many developing countries, leading to an increased per capita use of natural resources People are living longer in developed nations, putting a strain on the economies of those countries Life expectancy is still decreasing in Africa due to AIDS The standard of living is poor in many developing countries, leading to deprivation and suffering Fertility is falling due to exposure to endocrine disruptors released into the environment

Country Population millions Total Land area (million km2) Total annual electricity use Australia 144 0.14 1.6 Great Britain 19.7 8.2 22 China 1,295 9.6 150 Sudan 70 1.12 0.40 India 1,000 3.29 60 U. S. 300 9.63 400 Annually, the per capita electricity usage in Sudan is approximately what percent of the per capita electricity usage of the U. S.? 0.1 0.4 1 2 10