TABLE OF CONTENTS By about 20,000 BP, the global population consisted of an estimated two million foragers and hunters, leading a generally haphazard nomadic existence and possessing only objects which could be readily carried. But then small settlements and population clusters began to emerge in verdant canyons and alluvial flood plains evidently aided by the appearance of wild but edible cereals. The Middle East and more specifically the area between the Tigris River and Euphrates River of present-day Iraq often referred to as Mesopotamia which means The Land Between Two Rivers, Fig. 3.1 provided climatic and soil fertility conditions particularly suited to stimulate changes in human practices. About 12,000 BCE, the dog began associating with humans while sheep, goats, and cattle became domesticated beginning about 10,000 BCE [ ]. Wild barley then became a food staple and the initial stages of plant domestication were then undertaken. And so, the first of many riverine civilizations began to emerge.
It is estimated that by about 8000 BCE, some 500,000 people inhabited Mesopotamia. With increasing plant and animal domestication now extended to wheat and cattle, humans tended to become herders, then settlers, and finally tillers of the soil. The heterogeneous progression
identifies the principal human activities and the emergence of agriculture; one might claim that the discipline of primitive Agricultural Engineering was thus born. This progression also involved a substantially decreasing land-area-per-person needed to meet nutritional requirements and ...
