552 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1962 



civilization arose about 3500 B.C. in Mesopotamia, along the Tigris 

 and Euphrates. Another grew up in Egypt before 3000 B.C. and still 

 another in Crete. A fourth arose along the banks of the Indus in 

 western India, but whether this grew directly out of Neolithic begin- 

 nings or was a transplant of the Sumerian culture of Mesopotamia is 

 a matter of dispute. Urban civilizations developed in China at a 

 later date, and still later in some areas of tropical Central America 

 and in Peru. 



The urban societies of Mesopotamia, China, and Egypt maintained 

 complex centralized control of soil and water resources in order to 

 provide irrigation and to control floods. These "hydraulic" civiliza- 

 tions supported very dense populations with highly integrated social 

 systems. The individual peasant was allowed a small land area which 

 produced more food than his family needed. Such civilizations have 

 persisted in Egypt, India, China, and elsewhere to the present day, 

 with little change in the economic basis of life but with periodic 

 rises and declines. 



The ancient Mediterranean, Asian, and American urban civilizations 

 appear to have been isolated flowerings of human culture which cul- 

 minated in "golden ages" and then declined. The archeological record 

 abundantly reveals their wavelike nature. For additional informa- 

 tion, readers are referred to an earlier issue of Population Bulletin, 

 "The World's Great Cities: Evolution or Devolution?" (September 

 1960). 



THE A.D. ERA OF PERIOD II 



The United Nations study previously mentioned states that, at the 

 beginning of the Christian Era, the world's population was likely to 

 have been between 200 and 300 million people. Discussing the lack 

 of historic demographic information, the report states : 



Various kinds of evidence indicate that man's numbers became adjusted to 

 the food-producing capacity of the land in ancient times — increasing as it rose 

 and declining as it fell. Unfortunately little of this evidence is of a census type, 

 and most of the remainder does not provide a basis for estimating the number 

 of inhabitants of an area. Large parts of the world's population were subject 

 to some sort of census enumeration near the beginning of the Christian era, but 

 the information available from these censuses has limited value. Roman cen- 

 suses were taken for administrative purposes and were restricted to "citizens," 

 an expanding category as citizenship rights were extended to outlying regions. 

 Moreover only adult males were included in some of these censuses, while all 

 household members except "children" were included in others. Chinese censuses 

 at about this time provided reports on total population but interpretation of the 

 results involves many difficulties. Elaborate records were kept by the ancient 

 Incas, but their meaning is obscure. 



J. C. Russell, Professor of History at the University of New Mexico, 

 who has contributed much to the demographic history of the West, 



