That book illustrates one theory. What I stated is the theory taught to me as a student by the anthropology department at UCLA.
Edit:
I take that back. I just read the synopsis on wikipedia. The books' theory is exactly inline with my statement.
"The first step towards civilization is the move from nomadic hunter-gatherer to rooted agrarian society. Several conditions are necessary for this transition to occur: 1) access to high protein vegetation that endures storage; 2) a climate dry enough to allow storage; 3) access to animals docile enough for domestication and versatile enough to survive captivity. Control of crops and livestock leads to food surpluses. Surplus frees people up to specialize in activities other than sustenance and supports population growth. The combination of specialization and population growth leads to the accumulation of social and technologic innovations which build on each other. Large societies develop ruling classes and supporting bureaucracies, which in turn lead to the organization of nation-states and empires."
Edit:
I take that back. I just read the synopsis on wikipedia. The books' theory is exactly inline with my statement.
"The first step towards civilization is the move from nomadic hunter-gatherer to rooted agrarian society. Several conditions are necessary for this transition to occur: 1) access to high protein vegetation that endures storage; 2) a climate dry enough to allow storage; 3) access to animals docile enough for domestication and versatile enough to survive captivity. Control of crops and livestock leads to food surpluses. Surplus frees people up to specialize in activities other than sustenance and supports population growth. The combination of specialization and population growth leads to the accumulation of social and technologic innovations which build on each other. Large societies develop ruling classes and supporting bureaucracies, which in turn lead to the organization of nation-states and empires."