THE HUMAN SPECIES 



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existence — one in the Orient, based upon rice ; one in America, based upon 

 maize, beans, squash, and (in Peru) the white potato; and others in 

 various regions where such plants as yam, banana, taro, breadfruit, and 

 coconut came to support food-producing economies. 



Subsequent cultural progress was extremely rapid compared with 

 what had gone before, and its graph forms an ever-steepening upward 

 curve. Especially in the regions affected by the earliest of the Neolithic 

 cultures did discoveries, inventions, and social changes come crowding 

 close upon one another — urbanization, specialization of occupations, 



Fig. 31.21. Swiss lake swellers of the late Neolithic haul in their seine at Neuchatel, Switzer- 

 land. A part of their village, built on piles over the lake, is seen at the right. Whatever was 

 dropped sank into the mud of the lake floor and was preserved Among the things found 

 in the mud are many kinds of stone tools and wooden implements, cloth woven from flax 

 fibers, fishing nets and floats, and even the remains of grain, vegetables, fruits, and small 

 loaves of bread baked without yeast. (Courtesy Chicago Natural History Museum.) 



writing, money, bronze, iron, steel, and a multitude of other innovations, 

 not necessarily in the order named. Each major development wrought 

 changes in economy, and it is not easy to decide what and how many 

 cultural revolutions can be distinguished, even if we consider only the 

 history of Western civilization. Thus by some the rise of cities is ranked as 

 the urban revolution, while to others it seems no more than a logical out- 

 come of the Neolithic economy. All can agree on the industrial revolution, 

 in which power-driven machines came into use for the production and 

 transport of goods, and on the scientific-technologic revolution now in 

 progress, in which man is beginning to apply the results of science to 

 transform the world and his way of life. 



Prior to the discovery of food production man's numbers had always 

 been automatically kept in delicate balance with those of his wild food 



