It is usual to see man's early achievements evaluated in the light of progress in architecture, decorative art, production of implements, and social organization. Less commonly is considered the profound impact on the essence of animals and plants rendered by his early experiments in transplanting them from one environment to another, and yet, nothing man has ever done has been of greater importance, nothing of more lasting consequence to civilization. What was achieved during the first millennia of agriculture is still of paramount importance to modern society and will for ever so remain. Unconscious of his impudence, man forced plants to grow beyond the areas where by nature they were at home and, in doing so, was instrumental in reshaping their genetic constitution, thus enabling them to follow him in his. expansive migrations practically all over the world. Without wheat and barley, the pyramids, the ziggurats, the Greek temples, and the modern skyscrapers would never have been built. And yet these two important plants did not naturally belong to these lands, but were forced to adapt themselves to conditions prescribed by man's need for extended living space.
During the last few decades, the belief of last century, that the great monuments of the deserts of Egypt and Mesopotamia represented the beginnings of human culture, has been replaced by the realisation that these magnificent human achievements were preceded by much humbler establishments. The remains of primitive villages were found in Egypt, demonstrably much older than the pyramids, and deep beneath the towering ziggurats of Mesopotamia were disclosed correspondingly inconspicuous sites. However, on closer examination it was agreed that even these early remains were too far advanced in sophistication of technique and art to represent the very commencement of established human society.