Migration and Urbanization
Three great changes in the pattern and organization of human settlement
 The transition from hunting and fishing to agriculture. This transition
occurred in the Neolithic Age. Groups of hunters and gatherers, without permanent
homes, began to settle in more or less permanent dwellings (i.e., dwellings that
would last more than a season). This was the beginning of rural settlement.
Population increased markedly, probably from only a few million to many million.
 The emergence of cities. Cities first appeared in Mesopotamia (Iraq) around
3,500BC. Urban settlement gradually spread to the Nile Valley (Egypt), the Indus
Valley (Pakistan), and later to the Hoang-Ho Valley (China). Urban settlements in
Mexico and Peru developed later and independently. Urban areas required more
organized social bodies, and clearly they permitted higher standards of living.
Record-keeping became necessary as a supplement to human memory. Written
languages developed. In an important sense, recorded history began with the
establishment of cities. This form of civilization lasted for over 5,000 years, until
approximately 200 years ago. However, a substantial fraction of the population of
various countries and the world in general did not live in cities, but rather lived in
rural areas.
 The age of urbanization. In this period, a large fraction of a nation’s population
and even the world’s population (perhaps even more than half) reside in cities. This
phenomenon developed with the industrial revolution. Science, technology, and
powerful machinery have allowed the building of extremely large cities that
accommodate correspondingly extremely large populations with high density.
References:
Lewis Mumford, The City in History: Its Origins, Its Transformations, and Its
Prospects. New York: Harcourt, Brace, Jovanovich, 1961.
Jane Jacobs, The Economy of Cities. New York: Random House, 1969.
Table 1. Population of the World's Largest Metropolitan Areas, 1800, 1900, 1950,
and 2000: in thousands
Metropolitan Area
1800
1900
1950
2000
1950-2000
growth
factor
Tokyo, Japan
Mexico City, Mexico
Sao Paulo, Brazil
New York, USA
Mumbai (Bombay), India
Los Angeles, USA
Calcutta, India
Shanghai, China
Dhaka, Bangladesh
Delhi, India
Buenos Aires, Argentina
Jakarta, Indonesia
Osaka, Japan
Beijing (Peking), China
Rio de Janeiro, Brazil
Karachi, Pakistan
Manila, Philippines
Seoul, South Korea
Paris, France
Cairo, Egypt
Tianjin, China
Istanbul, Turkey
Lagos, Nigeria
Moscow, Russia
London, England
128
63
175
200
100
110
125
40
380
1,100
44
1,497
344
205
4,242
780
107
1,085
837
90
207
806
77
190
547
263
931
1,100
750
114
190
195
3,300
595
238
861
1,120
6,480
7,547
3,190
2,227
12,300
2,680
3,900
4,800
5,406
360
1,306
5,000
1,400
3,480
2,031
2,866
950
1,400
1,550
5,900
2,950
2,374
1,000
247
5,100
8,860
Sources: Chandler and Fox (1974) and GeoHive.
26,444
18,066
17,962
16,732
16,086
13,213
13,058
12,887
12,519
12,441
12,024
11,018
11,013
10,839
10,652
10,032
9,950
9,888
9,630
9,462
9,156
8,953
8,665
8,367
7,640
3.50
5.66
8.07
1.36
6.00
3.39
2.72
2.38
34.78
9.53
2.40
7.87
3.16
5.34
3.72
10.56
7.11
6.38
1.63
3.21
4.30
8.95
35.08
1.64
0.86
WHY DO CITIES GROW?
WHY DOES URBANIZATION OCCUR?
Let U = urban population
R = rural population
T = total population
T ≡ U+R
Urban growth refers to an increase to U.
Urbanization refers to an increase in U/T.
Urban growth can occur without urbanization if U grows, but R
grows faster.
Continued...
Thus, urbanization requires that the rate of urban population
growth exceed the rate of rural population growth.
Suppose that we define a society as “urbanized” if a majority of
its population lives in urban areas:
U/T > 0.5.
The first cities probably appeared about 5,500
years ago. However, an urbanized society constitutes
a new and fundamental step in the social development
of mankind.
Before 1850 no society (nation) was urbanized.
In 1900 only one country (Britain) was urbanized.
Modern Cities
Although cities have existed for 5,500 years, most urban growth and
urbanization have occurred quite recently in the history of
mankind–since 1750 or 1800.
1800: less than 2% of the world's population resided in cities of
100,000 or more
1850: 2.3% did
1900: 5.5% did
1950: 13.0% did
2007: 50.0% did
Continued...
1800: 20 cities over 100,000 worldwide;
perhaps 1 city over 1,000,000
1950: 900 cities over 100,000;
50 cities of 1,000,000
Historically, the growth of cities and urbanization have
occurred together with both U and U/T rising rapidly for a time.
Then, while U continues to grow, U/T remains fairly constant.
Thus, the process of urbanization has a beginning and an end.
Where have the urbanites come from? We have
three and only three possibilities:
1. Rural settlements grow larger and are reclassified as
urban.
2. Natural growth (excess of births over deaths) is
greater in the city than in the country.
3. Migration from rural to urban areas.
Consider each factor
1. Reclassification has never been of much importance.
2. Natural increase in rural areas is greater than in urban
areas.
1910: Number of children under 5 per
-1,000 rural white women 15 - 44 … 772
-1,000 urban white women 15 - 44 … 469
1970: Number of children under 5 per
-1,000 rural white women 15 - 44 … 407
-1,000 urban white women 15 - 44 … 357
3. Thus, migration must have been the major factor.
Why has rural-to-urban migration occurred?
People must have found it advantageous to carry out various
activities in a spatial concentrated fashion. We observe that
1. Households have found employment and wage opportunities to be
better in urban areas. We observe that average real income
rises with city size.
2. Business firms have found urban areas to be more
profitable areas in which to produce. We observe that output
per worker rises with city size
Factual evidence:
1. Germany (1964): output per capita
20-25% higher in million + cities compared to others
17% higher in million + cities than in cities of 0.5-1.0 million
2. Sweden (1967): average income per worker
33% higher in Stockholm than in small towns
12% higher in Stockholm than in other large metro areas
3. Japan (1965): average per capita income
20% higher in areas with 3,000 + persons per sq. kilometer than
in areas with 1,000-3,000 persons per sq. kilometer
70% higher in areas with 1,000-3,000 persons per sq. kilometer
than in areas with less than 500 persons per sq. kilometer
4. U. S. (1959): hourly earnings
30% higher in SMSAs of million + than in rural areas and small
towns
15% higher in SMSAs of million + than in SMSAs of less than
500,000
Urban advantages include:




scale economies: economies internal to firms
localization economies: economies internal to industries
but external to firms
agglomeration economics: economies internal to urban
areas but external to firms and industries
comparative advantage: economies that often are
related to location
The process of urbanization began in earnest at the time of
the industrial revolution, especially in England. However,
the urbanization that occurred in early 19th century
England could not have taken place if and agricultural
revolution had not also occurred.
A prerequisite for a significant degree of urbanization is
that persons living and working in agricultural areas produce a
surplus of food.
If the agricultural workforce is able to produce a surplus,
then a fraction (perhaps a large fraction) of the population can
live and work away from farms.
Significant technological developments occurred in
agriculture about 20 years before the advent of the industrial
revolution. These were:
1. Enclosure movement, which allowed landowners to
achieve scale economies and force redundant
labor out.
2. Harvesting derives like the reaper were critical
because the harvest was a big bottleneck.
3. Innovations in seeds and fertilizers.
Two important consequences of the agricultural revolution:
1. Part of the labor force was “freed” for work in industrial
pursuits (after migrating to the city).
2. A market was created for industrial goods.
Three trends in U.S. urban growth that persisted throughout the
20th century
 Movement to warm, dry places.
 Movement to “new” urban areas built around the car rather than “old”
urban areas built around public transportation.
 Movement to cities with stong human capital (skill) bases.
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