Human Populations Book, Principles of Environmental Science, Inquiry and Applications By Cunningham and Cunningham Presented by Doug Snyder

For every complex problem there is an answer that is clear, simple, and wrong. –H. L. Mencken

Is the World Overcrowded?

Views 1.We will exceed the carrying capacity of the planet 2.We will have more workers and smart people to solve our problems 3.We should have enough for everyone because it is only social justice problems that are causing some to be poor

History  Population Explosion in the last 200 years. Today 7 Billion  Global Human Population -grew fast recently 3 billion in 1960 to 6 billion in 1999  Maximum carrying capacity – probably 10-12 billion people – but suffering  Malthus (1766-1834) - showed exponential growth with food shortages predicted

 Karl Marx (1818-1883) - population growth results from poverty, resource depletion, pollution, social problems.

More Views on a Growing Population  Technology increased the carrying capacity of the planet

 But, food production has been based on cheap resources – production and transport  Formula I=PAT, I= Impact, P=Population, A=Affluence, T=Technology  Americans too much impact. 5 Planets!  Ecological Footprint = land required to support a lifestyle (goods and services) P.79, What do you think? o Ethics o Intergenerational justice

 Good for the economy? China.

o Economies of scale o Intelligent ingenious educated people o Larger consumer markets

What Makes Populations Grow?  Demography: “…encompasses vital statistics about people, such as births, deaths, and where they live, as well as total population size.”  2 main categories of populations: o Young, poor, and growing o Old, rich, and shrinking

 Conflict, economics, polities, and religion can keep contraceptive use low (Sub-Saharan Africa and Middle East) – ex. Chad and Congo, <10% use it  Russia – economy down, pollution, hyperinflation, crime, corruption – death rates up, birth rates down and more birth defects.  Africa – AIDS epidemic – 200 million person decline by 2050

Fertility Rates – Some definitions  Fecundity = “…ability to reproduce.”  Fertility = “…the actual production of offspring.”  Crude Birth Rate = “…number of births in a year per thousand persons.”

 Total Fertility Rate = “…the number of children born to an average woman in a population during her entire reproductive life.” – 12 or even 25 -30!  Zero Population Growth (ZPG) = “…when births plus immigration in a population just equal deaths plus emigration.” – replacement rates from 2.1 to 5 or more.  China’s One Child Policy – successful but abortions, infanticide, and abducted brides. boys to girls 140:100 in some regions

Mortality Offset Births and Life Expectancy  Crude Death (Mortality) Rates = “…deaths per thousand persons in any given year.” Usually 4 to 20 per 1,000  Rising global population in last 300 years mostly due to declining mortality  Life Expectancy = “…the average age that newborn infant can expect to attain in any given society.”  Life Expectancy rose from 40 to 67.2 in the last 100 years due mostly to nutrition, sanitation, clean water, and education  Disability Adjusted Life Years – accounts for premature death and loss of health  Globally, above annual income $4,000 USD GNP, longevity flattens out , Fig. 4.8  Dependency Ratio – number of workers vs non-workers

Life Expectancy is Related to Income

Projection of Shifting Dependency Ratios

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Fertility and Culture  Pronatalist Pressures – factors that cause people to want to have more children o Support for parents when parents are old o High infant mortality rates o Higher status in society o Income or work around the house o Cultures often value fertility o Male pride

In Low-tech Agricultural Areas Children are Additional Laborers

Fertility Rates by Country

Fertility and Culture Continued  Education and Income Effects o Ed and freedom lead to women limiting fertility o Career and job opportunities o Money earned important o In developed countries, raising children is expensive

Demographic Transition  Usually from high birth and death rates to low rates of both  Fig. 4.13, Stages 1.Pre-modern 2.Urbanizing/industrializing 3.Mature/Industrial – high population growth here 4.Post Industrial

 Death rates fall before birth rates do, so populations grow in stage 3

Stages of Demographic Transition

What stabilizes populations? 1.Growing prosperity and social reforms 2.Technology 3.Less developed nations can learn from other countries 4.Modern communication

Total Fertility Declines as Women’s Education Increases

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How to Complete the Transition Views  View 1 - Focus on justice first (hunger, poverty, violence, environmental degradation, and overpopulation are usually the result of an unjust society)

o Ex. Kerala India, resources distributed fairly to all – success o If focus on population only, this leads to racism and hatred of the poor

 View 2 – Focus on birth control

 Andra Pradesh – incentives for sterilizations

 Views from 1994 Conference on Population and Development

o Economic development, education, and empowerment of women, and health care needed o Must lower child mortality to lower birth rates o Increased income does not always equal benefits for children

Family Planning  Parents control number and spacing of kids through rational decisions  Birth control – anything (from celibacy and contraception to abortions)

 What we do now affects the future  Changes needed:

o Improved social, educational, and economic status for women o Improved status for children o Making decisions (calculated choice) o Social security and political stability (secure future) o Knowledge, availability, and use of birth control

Two Ways to Complete the Demographic Transition P. 88 • The Indian states of Kerala and Andra Pradesh exemplify two very different approaches to regulating population growth. • In Kerala, providing a fair share of social benefits to everyone is seen as the key to family planning. • The leaders of Andra Pradesh, on the other hand, have adopted a strategy of aggressively emphasizing birth control, rather than promoting social justice. • Both states have slowed population growth significantly. 4-28

World Population Projections

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Human Populations -

Human Populations. Book, Principles of ... Global Human Population -grew fast recently 3 billion in. 1960 to 6 ... nutrition, sanitation, clean water, and education.

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