1. Migration and Urbanization

2. 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.

3. 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.

4. 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.

6. 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.

7. 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.

8. 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.

9. 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

10. 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.

11. 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.

12. 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.

13. 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

14. 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

15. 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 19 th century England could not have taken place if and agricultural revolution had not also occurred.

16. 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.

17. 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.

18. 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.

19. Three trends in U.S. urban growth that persisted throughout the 20 th 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.