Chapter 5

“Processes and Cycles of Population Change”

The “J” curve

Worldwide Population Trends

World population increase has been a result of declining death rates, not increasing birth rates.

0

5

10

15

20

25

30

35

40

1936-1938

1946-1948

1955-1960

1960-1965

1965-1970

1970-1975

1975-1980

1980-1985

1985-1990

1990-1995

1995-2000

2000-2005

Birth rate Death rate

The “S” curve

Population growth is occurring more quickly in some parts of the world than in others.

10 Places With the Lowest Birth Rates Worldwide

1.10

1.10

1.10

1.00

1.14

1.16

1.15

1.15

1.15

1.14

Czech Republic

Armenia

Ukraine

Spain

Russian Federation

Slovenia

Macao Special Adminstrative Region

Bulgaria

Latvia

Hong Kong Special Administrative Region

Doubling Times

• Doubling time is the number of years it would take for a population to double at the current rate of growth.

• Countries with rapid population growth have low doubling times.

• As population increase slows, doubling time increases.

• The world doubling time is 51 years.• --North America--124

--Europe--0--Middle America--35--South America--41--N. Africa/SW Asia--35--Subsaharan Africa--27--South Asia--36--East Asia--87--SE Asia--41--Austral Realm--109--Pacific Realm--34

Russia’s demographic collapse

Why do women in some parts of the world have more babies than those in other parts of the

world?

Economic Factors Affecting Fertility

--agrarian society--children are economic assets

--industrial societies--children are economic liabilities.

--level of development--smaller family size is associated with a higher standard of living

Social Factors Affecting Fertility--traditional role of woman as a child-bearer--need for adult children to care for the elderly--preference for male child--high infant mortality rate--low literacy rate

--access to birth control information--machismo factor--religion

Political factors affecting fertility

--anti-natal policies.(China/India)

--pro-natal policies-concern over changing

demographics (France/Singapore)

-a “civic duty” in some places

Possible solutions?

• Encourage development• Broaden role of women in

society• Education• Decrease infant mortality• Establish pensions• Incentives for one child

The changing world ecumene(2000 years ago)

World ecumene 1000 years ago(10 million people)

World ecumene 1800(1 billion people)

World ecumene 1927(2 billion people)

World ecumene 1960(3 billion people)

World ecumene 1974(4 billion people)

World ecumene 1987(5 billion people)

World ecumene 1999(6 billion people)

World ecumene 2050(9 billion people)

The Great Population Debate“No Population Problem” Cornucopians: People are the world’s ultimate resource. Marxists: Poverty is the result of distribution problems, not

overpopulation.“There Is a Population Problem” Malthusians: Population growth, which is exponential, is

limited by growth in the food supply, which is arithmetic. Neomalthusians: In addition to food, other factors (such as

shortages of water and space) impose limits on continued growth.

Zero Population Growth: A halt in population growth is needed

“The ‘Population Problem’ Is a Complex Issue” Problems are the result of unequal distribution of resources

and high growth rates. Overconsumption by slow-growth countries is also

problematic.

Population Pyramids show the age and sex structure of given

populationsBy age cohort

Time

Stage 1 Stage 2 Stage 3 Stage 4

Naturalincrease

Birth rate

Death rate

Some basic terminology…

• …Birth Rate (aka Crude Birth Rate)

• …Death Rate (aka Crude Death Rate)

• …Total Fertility Rate (TFR)

2.1 is replacement rate

…Infant Mortality Rate

The demographic equation

TP=OP+B-D+I-E