In an except from Steven Solomon's 'WATER: The Epic Struggle For Wealth, Power, and Civilization,' Mesopotamia is the area between the Tigris and Euphrates rivers, which largely corresponds to modern day Iraq and surrounding lands. The violent floods from those two rivers gave rise to the earliest flood myths. The word Mesopotamia literally means "between the rivers," and it was the land of the great early civilizations of Sumer, Assyria, Akkadia and Babylon - in fact it is known as the cradle of civilizations. Though now a desert, in those ancient times Mesopotamia was filled with luxurious forests and vast farms of wheat and barley. Then the population dwindled and the land lost its fertility. Why?: