Now you ask us which one of the primary or secondary characteristics we believe to be the most important? Well I say agriculture and these are my reasons for my decision. If these ancient cultures did not realize and understand the importance of agriculture and learn to manipulate it into intensive agriculture they would have ceased to exist, and we would not be where we are today. I know you are saying hold on wait a minute all these ancient city/state collapsed and are no more, and for some of them there is hardly any archaeological evidence to show that they even existed, so what does this have to do with us? Even though these ancient civilizations collapsed and disappeared their methods and ways still lived on from one culture to another. If these people’s had not taken a crock and moved it to their liking and learn how to domesticate it to fit their needs they would have starved. This is how they accomplished intensive agriculture from my viewpoint. First they found a plants they would use as their main food crop and they felt that they could live off this crop and it would help their community to thrive and flourish. They moved this food crop onto a plot of land that they had learned how to cultivate and fertilize properly. Next they learn how to control their water sources and were able to irrigate this plot of land when needed to ensure crop growth. The controlling of the water source with also a huge feat within itself, it took a lot of thinking and planning and manpower to accomplish such a plan. But when all these factors were put together your final result is a domesticated crop, yielded by use of intensive agriculture. Also included in this segment is the importance of the domesticated animal. These cultures learned the importance of domesticating the animal to use for labor in building, traveling and working the fields where the intensive agriculture was taking place. Also with the domestication of animals it gave them another food source. They could get meat, milk, oils, and much more from animals. Also they could use their other parts like the hide and bones for daily living practices. Domesticating an animal was less time-consuming than going out to hunt, which in turn allowed them time to practice and involve their intensive agriculture.
I would also like to say that I believe the secondary characteristic writing was also important because without some form of writing we would not be able to identify some of these many cultures that we are finding today.