Early Population Growth
World Population Growth
Human Population: Fundamentals of Growth
Population Growth and Distribution
World Population Growth, 1750–2150
Source: United Nations, World Population Prospects, The 1998 Revision; and estimates by the Population Reference Bureau.
World Population Growth
http://www.susps.org/overview/numbers.html
World Population Growth
THE WORLD AT SIX BILLION: HIGHLIGHTS
1. World population crossed the six billion threshold on October 12, 1999.
2. World population is projected to cross the 7 billion mark in 2013; the 8
billion mark in 2028; the 9 billion mark in 2054. World population nearly
stabilizes at just above 10 billion after 2200.
3. It has taken just 12 years for the world to add this most recent billion
people. This is the shortest period of time in world history for a billion people
to be added.
4. World population did not reach one billion until 1804. It took 123 years to
reach 2 billion in 1927, 33 years to reach 3 billion in 1960, 14 years to reach
4 billion in 1974 and 13 years to reach 5 billion in 1987.
5. The highest rate of world population growth (2.04 per cent) occurred in the
late 1960s. The current rate (1995-2000) is 1.31 per cent.
THE WORLD AT SIX BILLION: HIGHLIGHTS
6. The largest annual increase to world population (86 million) took place in
the late 1980s; the current annual increase is 78 million.
7. Of the 78 million people currently added to the world each year, 95 per
cent live in the less developed regions.
8. Eighty per cent of the world currently reside in the less developed
regions. At the beginning of the century, 70 per cent did so. By 2050, the
share of the world population living in the currently less developed regions
will have risen to 90 per cent.
9. The population of the world is aging. The median age increased from 23.5
years in 1950 to 26.4 years in 1999. By 2050, the median age is projected to
reach 37.8 years. The number of people in the world aged 60 or older will
also rise from the current one-of-ten persons to be two-of-nine by 2050.
Currently around one-of-five persons in the developed countries are aged
60 or older; in 2050 nearly one-of-every three persons will be aged 60 or
older.
THE WORLD AT SIX BILLION: HIGHLIGHTS
10. World life expectancy at birth is now at 65 years, having increased by a
remarkable 20 years since1950; by 2050 life expectancy is expected to
exceed 76 years. However, in spite of these impressive gains, recent years
have shown a devastating toll from AIDS in a number of countries. In addition,
in some Eastern European countries, health has been deteriorating and
mortality, particularly among adult males, has been rising.
11. Couples in developing countries today have on average 3 children each;
thirty years ago they had six. More than half of all couples in developing
countries now use contraception.
12. The number of persons who have moved to another country has risen to
over 125 million migrants today from 75 million in 1965.
13. The world has become increasingly urban. Currently, around 46 per cent
of the world population lives in urban areas; the majority of the world’s
population will be urban by 2006.
_______________
Source: United Nations Population Division
Let’s take a look at how all this
began…
First Agricultural Revolution
• Since the beginning of time Humans used Hunting and
Gathering as their main method of attaining food.
• around 8000BC – humans learned to cultivate crops,
domesticate animals. They shifted from Hunters and
Gatherers to Farmers.
• Impact was great - larger numbers of people could now be
supported, because of more food.
• This first began in SW Asia - Mesopotamia, between the
Tigris and Euphrates Rivers (modern Iraq).
• This area had rich soils and lots of water. The rivers flooded
annually leaving behind excellent fertilized soil.
• Wheat, barley, oats, peas, sheep and goats.
• Also occurred in delta (mouth of rivers!) areas.
• Social systems began to evolve; society became more
complex. You now need all types of rulers and
governments.
• Ideas spread (spatial diffusion):
• into the Nile area,
• south into Africa,
• west along Mediterranean,
• north into Europe,
• east to India,
• eventually China.
• Agriculturalists became powerful.
• Hunters and gatherers were restricted to marginal
lands.
• Six distinct hearth regions emerged.
• Agriculture led to the rise of complex civilizations and
social organizations.
• Greek and Roman.
• Population growth soared.
• Other skills emerged - metallurgy, paper, gunpowder.
Population Momentum: Over time
growth occurs exponentially
(compounding):
Pop.
2 – 4 – 8 – 16...
Time
As opposed to arithmetic growth:
1 – 2 – 3 – 4...
Food
Time
(we will find out later this is the way
food production grows – Can this
type of growth feed the world’s
population?)
Second Agricultural Revolution
• mainly in Europe (around 1600)
• Coincided with the Scientific Revolution at end of the
Middle Ages.
• Improvements based on science and technology - food
production boosted.
• eg. Nitrogen as a fertilizer was discovered, canal
construction, swamp lands were drained and sheep were
cross bred for desirable characteristics.
• Within 100 years population went from 500M to about
800M.
• Large urban areas emerged – Urbanization was just
beginning.
Trends in Urbanization, by Region
Urban Population
Percent
84
83
75
75
60
41
47
30
38
37
17
15
World
55
54
53
Africa
Asia
1950
2000
Latin America/
Caribbean
More
Developed
Regions
2030
Source: United Nations, World Urbanization Prospects: The 2001 Revision (medium scenario), 2002.
© 2003 Population Reference Bureau
Industrial Revolution
• Characterized by the application of machines to
farming, eg., steam powered tractor, threshing
machines, grist mills, pumps.
• Population soared - from 1750 to 1800 another
200M people were added to world total.
• By 1850 the total was 1B.
• Could food production keep up?
• Coal was important and population therefore began to
cluster around important coal producing regions.
• Eg., Rhine-Ruhr of Germany, Eastern Europe, Northern
England.
• Population began a dramatic rural to urban shift as
lifestyles began to change. This of course is called
Urbanization. People stopped being farmers, they realized
that they could go to work – let’s say in the local factory –
and purchase the food they needed. The people that
remained farmers had to grow surpluses of food. They
would keep want they needed and sell the surplus. Sounds
simple!
World Population Growth
Date
8000BC
4000BC
1AD
1650
1850
1930
1950
1970
1988
1999
Population
5M
87M
250M
500M
1.1B
2B
2.5B
3.6B
5.1B
6B
Source: http://www.sru.edu/depts/artsci/ges/d-3-2.htm
The End!