is the world overpopulated?

Is the world overpopulated?

Is the world overpopulated?

Siberia

Is the world overpopulated?

Calcutta

Is the world overpopulated?Africa

Congo

Kenya (Nairobi)

Is the world overpopulated?

Why do Western European governments encourage more babies?

What does “overpopulated” mean?

Ethiopia - 70 million - overpopulated

Germany - 80 million - not overpopulated(Ethiopia is 3x bigger)

Where do humans live?

How many humans are there?What is the result of population

increase?

Starvation? Malthusian TheoryThomas Malthus -

1798

The world’s population is increasing faster than food supply.

(Food supply grows linearly, population grows exponentially.)

Neo-MalthusiansHuman suffering is

occurring on a scale unimagined even by Malthus.

Overpopulation must be addressed now.

Questions - ● How can we make sense of population

changes?● How can we make predictions?

● Why is the highest growth rate in underdeveloped states?

● Why do the richest states have the lowest growth rate?

Answers -Demographic Transition Model

Demographic Transition Modela theory which explains human population

change

Demographic Transition Modela theory which explains human population

changebased on ● idea that all societies want to

transition from pre-modern to postmodern

● experience of richer, fully developed states (Europe, US, Australia…)

Stage 1

Stage 1Pre-modern, hunter-gatherer stage

Birth ratehigh

Death ratehigh

What’s going on?Why?

Stage 1Pre-modern, hunter-gatherer stage

What’s going on?Why?high IMR,low life expectancy

Stage 1Pre-modern, hunter-gatherer stage

Total populationlow, low growth rate

Examplesno states - only areas of Amazon, remote savannas in Africa, highlands of Papua New Guinea

Stage 2

Stage 2Urbanizing-Industrializing stage

Birth ratehigh, stable

Death ratedeclines

What’s going on?Why?

Stage 2Urbanizing-Industrializing stage

What’s going on?Why?agricultural revolution & technical

innovation → specialization & urbanization→ industrialization

Stage 2Urbanizing-Industrializing stage

Total Populationpopulation explosion! death rates drop, birth rates remain high → youthful population

cultural lag = conditions change, but culture is lagging behind

Stage 2Urbanizing-Industrializing stage

Examplesstates in Africa, Central America and parts of Southeast Asia

(late Stage 2)

Stage 3

Stage 3Mature Industrial

Birth ratedeclining

Death ratedeclining

What’s going on? Why?

Stage 3Mature Industrial

What’s going on? Why?● More people in processing,

manufacturing, and service than farming → urbanization → lower TFR

● Improved health care, technology, education, etc.

● Early Stage 3 very different from Late Stage 3

Stage 3Mature Industrial

More on lower TFR:Urbanization = re-evaluation of costs and

benefits of having children.Educated women = more women

working, more contraceptive use, fewer kids

Cultural lag is over

Stage 3Mature Industrial

Total Population:young people % = older people %Examples:(most states are in Stage 3)early Stage Three - India, Brazillate Stage Three - China, Chile

Stage 4

Stage 4Fully Developed, Postindustrial

Birth ratelow, stable

Death ratelow, stable

What’s going on? Why?

Stage 4Fully Developed, Postindustrial

What’s going on? Why?● economic shift has occurred - most people

work in service (few in manufacturing, almost none in agriculture)

● technology and education still increasing, but can’t lower death rate any more

● most people have 1 or 2 children, some have none

Stage 4Fully Developed, Postindustrial

Total Population:older TFR is low

Examples:U.S., France, Japan

Stage 5? Does it exist?Birth rate falls below death rate,causing net population loss.

Will states disappear?

Population Pyramids show population by gender and age

groups● economic

conditions

● standard of living

● future population

Population Pyramids Classic Pyramid

Population Pyramids Classic Pyramid

population explosion!Largest age cohorts = under 15 year olds

Why does this matter?more dependents than providers

Which DT stage(s) have this shape?What else can we predict about a

population with this shape?

Population Pyramids Column Shape

stable population growth (low, even zero)

closer to replacement level→ more cylindrical in shape

replacement level = TFR of 2.1

Which DT stage(s) have this shape?What else can we predict about a

population with this shape?

Population Pyramids Column Shape

Population Pyramids Inverted

Population Pyramids Inverted

total population is shrinkingTFR is under 2.1

Why does this happen?Could a state shrink into nonexistence?How could this be avoided?

Population Pyramids Inverted

Examples: Japan, Italy, SwedenWhy?

higher cost of living in urbanized area+ transition of children from asset to

expense= changed attitudes, lower TFR

different kind of example - Russia and former Soviet states - inverted

b/c lack of resources, jobs, health care, other services

Population Pyramids and the DTM

Which stage?How can you tell?

Population Pyramids and the DTM

Which stage? early- to mid-Stage ThreeHow can you tell?

Population Pyramids and the DTM

Which stage?How can you tell?

Population Pyramids and the DTM

Which stage? late Stage 3, early Stage 4How can you tell?

Population Pyramids and the DTMWhich stage?How can you tell?

Population Pyramids and the DTMWhich stage? Stage 4How can you tell? What else does this

pyramid show about India?

Population Pyramids and the DTMpopulation momentum =“snow ball” effect population growth after fertility stabilization (TFR of 2.1)

Use the DT model to predict - What will happen to...

...least developed countries? (sub-Saharan Africa, Middle East, Central America, most of Asia)

...countries further down development path? (China, India, Mexico, South America)

...countries that are fully developed?(W Europe, US / Canada, Australia)

What causes exceptions?religious influencessome states in Middle East and South

America are maintaining high birth rates

state-sponsored policiesChina - One-Child Policy - wealthy and

growing middle class wants to have more children despite penalties

Population “Quiz”http://media.plaidavenger.com/pyramidmc/

John Boyer, Geography ProfessorVirginia Tech