Preconditions for Development of Agriculture *

 

… Of the many wild species auditioned by humans as potential domesticates, few passed the test, and in some areas none did.  Indeed, the availability or nonavailability of nutritious and easily domesticable plants and animals may have been a crucial determinant of the geography of early agriculture, and therefore a crucial determinant of much later human history.  Of several hundred thousand plant species, only a few hundred have been domesticated successfully, and most of these are of marginal importance when compared to the dozen major crops that provide most of the world’s food today.

 

The qualities humans sought in potential domesticates were hardiness, nutritional value, adaptability, and the ability to breed under varying conditions.  Animals had to be sociable; able to live and breed in large, compact herds; and characterized by social hierarchies that predisposed them to follow leaders, whether animal or human.  The nature of the available domesticates may also help explain the chronology of early domestication.  Jared Diamond has argued persuasively that the potential domesticates available in the Fertile Crescent were unusually varied, attractive, and easy to domesticate and that those features go a long way toward explaining why agriculture appeared first in this region.  The ease of domestication of the region’s main cereal crops can be demonstrated by the remarkably small change they have undergone from their wild state; wild barleys and wheats were abundant, nutritious, and easy to harvest and grow. 

 

In contrast, the domestication of maize was much trickier; teosinte had to be trained for several millennia before it could support large populations.  The lack of potential animal domesticates after the megafaunal extinctions of the early Holocene era also slowed the adoption of agriculture in Mesoamerica.  There, only the dog and turkey were domesticated, and neither was as valuable as the main animal domesticates of the Fertile Crescent.  The paucity of animal domesticates deprived American farmers of traction power, manure, and a rich source of protein.  In Papua New Guinea, too, the nutritional limitations of local domesticates such as taro, which contains little protein, lessened the demographic impact of agriculture and restricted its spread.

 

The existence of potential domesticates and of much relevant ecological knowledge constitutes crucial preconditions for agriculture.  But these factors cannot explain the timing or the motivation for the transition to fully developed agriculture.

 

  * David Christian, Maps of Time, (Berkeley: University of California Press, 2004), p. 230.