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KEY QUESTION #2:

WHY DO

POPULATIONS RISE

OR FALL IN

PARTICULAR PLACES?

(8 slides)

World Death Rates

Birth Rates

Natural Rate of Increase

Life Expectancy at birth

KEY QUESTION #2: WHY DO POPULATIONS

RISE OR FALL IN PARTICULAR PLACES?

• We can trace alarms about population growth back to

1798

– British economist Thomas Malthus published an essay

– In his work he claimed the world’s population was

increasing faster than the food supplies needed to sustain it

– His reasoning:

• Food supplies grow linearly

• Population grows exponentially

Thomas Malthus on

Population

Malthus, responding to Condorcet, predicted population would outrun food supply, leading to a decrease in food per person.

Assumptions

• Populations grow exponentially.

• Food supply grows arithmetically.

• Food shortages and chaos inevitable.

An Essay on the Principle of Population, 1798

0

50

100

150

200

250

300

1 2 3 4

Population

Food

Food Population

2 2

4 4

8 16

16 256



• His assumptions wound up being false in the long

run…

– Today there is no confines of food production---can grow

lots of things in lots of places

– Today, agricultural goods are exchanged throughout the

world

– New agricultural methods exist today that didn’t in 1798;

acreage of land for farming has grown rapidly

• Example: the Irish potato blight of the 1700s would never

happen today to a wealthy country



• Malthus’s theory still has followers

• Today, they are called “Neo-Malthusians”

– Point out that human suffering is now occuring on a scale

unimagined by even Malthus

– They feel overpopulation should be addressed now



• To calculate demographic change for a

place, we must look at:

– Births, deaths, immigrants & emigrants

• Worldwide TFR right now is

2.6(replacement level is 2.1)

• What do we know about the role of women

that affects the TFR?

World Population Growth Rate of natural increase (does not take into account immigration and

emigration).



• By 2025, we should have 8 billion people

• By 2050, we should have almost 9.5 billion

• An easy way to look at population growth is calculating “doubling time”

– The amount of time it takes for the population of a place to double

– For the world right now, it is about 58 years

• Took 16 centuries to go from 250 million to 500 million people(in 1650); population then doubled after 170 years, then after 110 years, then after 45 years

• Therefore, doubling time has slightly slowed down


RISE OR FALL IN PARTICULAR PLACES? • Significant demographic differences exist between regions (as

previous map shows)

• Differences also exist within states

• Great example is India

– Government encourages birth control

– 1970s : forced sterilization on any man with 3 or more kids

– 2004 : India’s most populated state instituted a policy that

required two people be sterilized for a shotgun license; and 5

sterilized for a revolver license

• Wealthy landowners would pay their workers or others to get

sterilized so they could buy guns

– Other issues exist today: people are granted access to housing &

extra food if they get sterilized; sonograms to detect gender are

outlawed because of abortion rate of unborn females

Population Growth in India

• Significant

demographic

variations occur

within

countries.

– In India,

growth rates

are higher in

the east and

northeast.

Maharashtra, India. A sign reads “free family planning sterilization

operation” closed in 1996.

Missing Indian Female Population • Missing female population in India

– Sex determination tests outlawed (1994):

• Nobody ever convicted of infringing the law.

• Ultrasound for “abdominal cyst”: 500 rupees ($11).

• Abortion: 2,000 rupees ($44).

– 25% of all female deaths between the age 16 and 24 are due to

“accidental burns”.

– Between 5,000 and 12,000 “dowry deaths” per year.

– Sex ratio is still declining:

• 962 girls for 1000 boys (1981).

• 945 girls for 1000 boys (1991).

• 927 girls for 1000 boys (2001).

• Can go as low as 770 in some regions.


RISE OR FALL IN PARTICULAR PLACES? • DEMOGRAPHIC TRANSITION MODEL

– Shows the sequence of stages in population growth

– Involves 4 stages

• 1)LOW GROWTH

– High birth rates, high death rates; little growth

• 2)HIGH GROWTH

– High birth rate, declining death rates; sustained &

significant growth

• 3)MODERATE GROWTH

– Declining birth rate combines with already declining death

rates lead to continued, but slower growth

• 4)LOW GROWTH or STATIONARY STAGE

– Low birth rate, low death rates; very low rate of growth

The Demographic Transition

The Demographic Transition (COMPLETE)



• STAGE ONE

– Plagues & famines impacted many regions in history

• STAGE TWO

– Beginning of the Industrial Revolution sent Europe & the

USA into stage 2

– Also, a revolution in agriculture(2nd Agricultural Revolution)

had to occur

• 1st Ag. Rev. was the growing of crops; 2nd involved use of

new technology/techniques

– Rest of the world entered stage 2 in the 1900s

Beginning of Demographic

Transition



• STAGE THREE

– Urbanization, wealth, contraception & medical advances led many countries from stage 2 to 3

– Roles of women changed dramatically as well(more involved in working than raising families; many had smaller families than in past)

• STAGE FOUR

– The places where women are the most educated & most involved in the labor force are in stage 4

– Stage 4 can even lead to a “Stage 5” where negative population growth occurs

Fertility Transition in some

Countries, 1962-2004

0

1

2

3

4

5

6

7

8

Nigeria

Philippin

esEgypt

BangladeshIn

dia

Mexico

Indonesia

Brazil

China

South K

orea

TFR

1962 1982

1990 2000

2004

Family Planning

Result of Pregnancies, World 2000

63%15%

22%

Live births

Miscariages

Abortions

• Concept – Designed to help families achieve a

desired size.

– 1/3 of the population growth in the world is the result of incidental or unwanted pregnancies.

– 210 million pregnancies in the world per year, of which 100 million are unwanted pregnancies (47%).

– 46 million abortion per year.

– 500,000 women die each year from unsafe abortions.

– 49% of pregnancies in the US are unwanted.

– If women could have only the number of children they wanted, the TFR in many countries would fall nearly to 1.

Women Using Family Planning

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