Chapter Seven: Human Population

Life expectancy

Average age a newborn can expect to attain in any given society (has risen from an average of 30 to 68 over the past century)

How is the population within more developed countries?

Average age is about 40, and populations are expected to stabilize or decline

What became of China's one child policy?

China's one child policy has decreased the fertility rate from 6 in 1970 to 1.54 in 2010. However, it caused social problems and resulted in an increase in males and a decrease in females

What is stage 2 of demographic transition?

Economic Development brings better standard of living thus death rates fall. Birth rates stay constant or even rise. (Stage II)

How do economists feel about the population?

Economists often disagree with ecologists, arguing that economic and technological growth will enable us to solve these problems.

How does the population affect the environment?

Effects of population on the environment are not due to numbers alone (I=PAT). A single American living an affluent lifestyle produces more pollution than an entire village of farmers in Africa.

Where have fertility rates declined?

Everywhere except in Africa

Pronatalist pressures

Factors that increase the desire for children (pleasure, pride, comfort, support for the elderly, source of family income and labor, social status, replacement of members in society, etc.)

How does a higher income affect fertility rates?

In developing countries, higher income often means families can afford more children, thus fertility often increases, rather than decreasing as it does in developed countries. In less-developed countries, adding another child to a family usually does not cost much, while in developed countries, raising an additional child can carry significant costs.

Where is the dependency ration a problem?

In the U.S., fewer working age people will have to support many more retired people, and this is a problem for the Social Security system. Similar problems are developing in other countries around the world causing countries to rethink their population policies.

Total fertility rate

Number of children born to an average woman in a population during her life

Crude death rate

Number of deaths per thousand persons in a given year (Poor countries average about 20 while wealthier countries average about 10)

Zero population growth

Occurs when births plus immigration in a population equal deaths plus emigration. ZPG Is a rate of 2.1 children per couple, not 2.0, because some people do not have children and some children do not survive to reproductive age.

Life span

Oldest age to which members of the species survive

Why may birth dearth have happened?

One reason that birth rates may have dropped in developed countries is that toxins and endocrine disrupters that are pollutants interfere with sperm production. Sperm numbers and quality have fallen by half in the last 50 years.

What are more developed countries like in their demographic world?

Wealthy, old, and mostly shrinking

How does child mortality affect fertility rates?

When child mortality is high, parents tend to have high numbers of children to ensure that at least some survive. Improving child survival would reduce the number of births (Land reform, political rights, job opportunities for women, and improved health for women translate into better survival for children and therefore lower fertility)

How does education affect fertility rates?

When women have more opportunities to earn a salary, they are less likely to have many children. Education and socioeconomic status are usually inversely related to fertility in wealthier countries.

What conditions are necessary for demographic transition?

improved standard of living confidence that children will survive improved status of women availability and use of birth control

Who was Thomas Malthus?

(1798) wrote An Essay on the Principle of Population in which he showed that human populations increase exponentially.

How much of the population is made up of less-developed countries?

80% of the world population, and will be account for 90% of projected growth

Why would a rapidly growing country have a low crude death rate?

A rapidly growing country has a high proportion of young people

Where are less-developed countries found?

Africa, Asia, Latin America

Family planning

Allows couples to determine the number and spacing of their children

How is the population in Europe and Japan?

Birth rates are declining due to couples choosing to have fewer or no children.

Natural increase

Crude birth rates minus crude death rates

What is the primary cause of most population growth in the last 300 years?

Declining mortality due to improved nutrition, sanitation, and education (not medicine)

Why are ecologists concerned with the population?

Ecologists are concerned that overpopulation will cause environmental degradation that will threaten the ecological life-support systems on which we depend.

Who is Julian Simon?

Economist who believes that human ingenuity will be able to solve the problems associated with population growth

What is demography?

Encompasses vital statistics about people such as births, deaths, distribution, and population size (current estimate for world population is 7.2. billion for 2013)

Population momentum

Even if total fertility rates were to fall, the population would continue growing as young people enter reproductive age (a stable population has the same number of people in each age group, while declining populations have more old people)

How many people are born and die every second? What is the net gain?

Every second 4 or 5 children are born while only 2 people die. There is a net gain of roughly 2.5 persons per second.

When did population growth begin? Why?

Human population began to increase rapidly after 1600 due to agricultural developments, better sources of power, and better health care and hygiene.

What does I = PAT stand for?

I = environmental impact P = population size A = affluence T = technology

How does technology affect population growth?

It increases the carrying capacity. Technology can boost carrying capacity as we make progress in agriculture, engineering, commerce and medicine. These achievements make it possible to support many more people per unit area. However, much of our growth has been based upon cheap, abundant fossil fuels. Will rising fuel prices constrain food production and distribution?

When did the population reach 3 billion?

It took 150 years to double that to 3 billion (in 1960).

When did the population reach 1 billion people?

It took thousands of years to reach 1 billion people (in 1804).

What is stage 1 of demographic transition?

Pre-Modern Society - Poor conditions keep death rates high; birth rates are correspondingly high. (Stage I)

How do social justice advocates feel about the population?

Social justice advocates argue that the root cause of the problem is inequitable distribution of the Earth's resources.

What are the two demographic worlds?

There are 1) less-developed countries and 2) more developed countries

Why is birth dearth an issue?

There are concerns in all these countries about a lack of young people to be soldiers, workers, and taxpayers.

Why didn't population growth begin earlier?

Until the invention of agriculture 10,000 years ago, the human population was a few million people. Populations were held in check by diseases, famine and war. Early societies regulated their population through cultural taboos, abstinence and infanticide.

Birth reduction pressures

Higher education and personal freedom for women often result in decisions to limit childbearing.

What is the pessimistic view of demographic transition?

Lester Brown warns that poorer countries may be caught in a demographic trap. The population is growing so rapidly that there are not enough resources to complete modernization and enter stage IV. People who take this view urge birth control, education, and national policies that limit population growth.

Birth control

Any method used to reduce births (long breast-feeding that suppressed ovulation, taboos against intercourse while breast-feeding, abortion, folk medicines, etc.)

How is the population in Russia?

The end of the Soviet Union caused economic collapse. Death rates have risen dramatically and the birth rate is among the lowest in the world.

When did the population reach 5-6 billion?

The increase from 5-6 billion took only 12 years (1972). The population tripled in the twentieth century

Dependency ratio

The number of non-working compared to working individuals in a populations

What is the current world population and how much is it growing?

Current world population is greater than 7 billion and growing at 1.13% per year. Global population will double in 62 years if conditions remain unchanged.

What is the debate between the Malthus and Karl Marx viewpoints?

Debate about whether human population growth causes environmental degradation (Malthus) or whether human population growth results from poverty and resource depletion (Karl Marx).

What is stage 4 of demographic transition?

Developed Countries - Transition is complete and both death and birth rates are low and population is in equilibrium. (Stage IV)

How do emigration and immigration play a role in human population dynamics?

Developed regions expect 2 million immigrants a year for next 50 years. Immigration is a controversial issue. "Guest workers" often perform dangerous or disagreeable work, while being paid low wages with few rights. Locals complain immigrants take away jobs and overload social services.

What factors might improve family planning?

Improved education and economic status for women Improved status for children Increased sense of social responsibility Financial and political stability Effective and acceptable birth control methods

What is stage 3 of demographic transition?

In a mature industrial economy, birth rates begin to fall as people see that most of their children survive. (Stage III). Populations continue to grow due to population momentum.

Total growth rate

Includes immigration, emigration, births and deaths

How can more people be beneficial?

More people mean larger markets, more workers, and increased efficiency due to mass production. Greater numbers also provide more intelligence and enterprise to overcome problems.

Where can birth dearth be found?

Most European countries, as well as Japan, Singapore and Taiwan, are experiencing negative growth rates.

Birth dearth

Negative growth rates

Where are more developed countries found?

North America, Western Europe, Japan

Crude birth rate

Number of births in a year per thousand. (Not adjusted for population characteristics such as number of women of childbearing age.)

Demographic transition

Pattern of falling death rates and birth rates due to improved living conditions accompanying economic development (there are four stages involved)

What are less-developed countries like in their demographic world?

Poor, young, and rapidly growing.

How does population growth stay checked?

Population growth is checked by famine, disease, and cultural factors (e.g., late marriage).

Why does society feel a need to replace its members?

Society's need to replace its members may be codified into cultural or religious values (having few children can be seen as a pity, and controlling fertility may be taboo. Some families may have more children to have a boy that is more valued to support the family and bring male pride)

Is demographic transition happening now?

Some demographers think it is occurring now in developing countries

Social justice and demographic transition

Still other demographers believe that in order for the demographic transition model to work, resources must be distributed more equitably. They believe that the world has enough natural resources, but inequitable social and economic systems cause maldistribution. Many rich countries, when they were colonial powers, extracted the wealth from countries that were their colonies. Some of the world's poorest countries had rich resources and adequate food supplies before they were impoverished by colonialism (also consider the rights of other species)

How is the population in Africa?

The AIDS epidemic has hit Africa the hardest. In Zimbabwe, Botswana, Zambia and Namibia, up to 39% of the population is HIV positive. More than 2/3 of the 15 yr. olds now living will die of AIDS before age 50. Life expectancy in Botswana has dropped to 31.6 years.