According to the theory, all this would have been true except in the valleys of rivers and in oases in the growing deserts. Here, in the only places where water was left, the men and animals and plants would have clustered. They would have been forced to live close to one another, in order to live at all. Presently the men would have seen that some animals were more useful or made better food than others, and so they would have begun to protect these animals from their natural enemies. The men would also have been forced to try new plant foods--foods which possibly had to be prepared before they could be eaten. Thus, with trials and errors, but by being forced to live close to plants and animals, men would have learned to domesticate them. THE OLD THEORY TOO SIMPLE FOR THE FACTS This theory was set up before we really knew anything in detail about the later prehistory of the Near and Middle East. We now know that the facts which have been found don’t fit the old theory at all well. Also, I have yet to find an American meteorologist who feels that we know enough about the changes in the weather pattern to say that it can have been so simple and direct. And, of course, the glacial ice which began melting after 12,000 years ago was merely the last sub-phase of the last great glaciation. There had also been three earlier periods of great alpine glaciers, and long periods of warm weather in between. If the rain belt moved north as the glaciers melted for the last time, it must have moved in the same direction in earlier times. Thus, the forced neighborliness of men, plants, and animals in river valleys and oases must also have happened earlier. Why didn’t domestication happen earlier, then? Furthermore, it does not seem to be in the oases and river valleys that we have our first or only traces of either food-production or the earliest farming villages. These traces are also in the hill-flanks of the mountains of western Asia. Our earliest sites of the village-farmers do not seem to indicate a greatly different climate from that which the same region now shows. In fact, everything we now know suggests that the old theory was just too simple an explanation to have been the true one. The only reason I mention it--beyond correcting the ideas you may get in the general texts--is that it illustrates the kind of thinking we shall have to do, even if it is doubtless wrong in detail. We archeologists shall have to depend much more than we ever have on the natural scientists who can really help us. I can tell you this from experience. I had the great good fortune to have on my expedition staff in Iraq in 1954-55, a geologist, a botanist, and a zoologist. Their studies added whole new bands of color to my spectrum of thinking about _how_ and _why_ the revolution took place and how the village-farming community began. But it was only a beginning; as I said earlier, we are just now learning to ask the proper questions. ABOUT STAGES AND ERAS