Introduction
We had two major goals going into the concept map. First of all, we wanted to detail the various places that had either developed the wheel on their own or made major refinements to it. That list included the following eight countries or cultures by the time we had completed our research: Early Mesopotamian civilizations such as Sumeria, pre-Russian cultures like the Andronovo ones, Mesoamerican civilizations, early China, Greece, Egypt, Rome and finally Celtic cultures in central Europe. For each culture, we tried to give a brief background of what their version of the wheel was, what any refinements they may have made to it were, the approximate time period for each refinement and what uses they put the wheel to. There were three major areas where the wheel was of interest to these early cultures: transportation, war and entertainment. The wheel made it possible for overland transport of goods, which was used by several societies, to be both possible and profitable. Meanwhile, chariots were used as weapons of war (as platforms from which archers could shoot on the move) and pitted against one another in races to entertain the people of a given civilization. The three main conveyances that were used over much of our timeline were simply a rude two-wheeled cart, a four-wheeled wagon and several different types of chariot. The carts grew out of a sledge-and-roller system as discussed at length in the timeline, while the four-wheeled wagons were usually extensions of the cart with more carrying capacity and stability. Chariots, constructed out of iron or wood, were used primarily for war and secondarily for entertainment. As is also discussed in the concept map, iron chariots came to be used in war for their superior durability and protection, while the lighter, faster wooden chariots were relegated to racing. Our concept map traces the idea of the wheel and improvements to it, and as such, takes place in a fairly linear timeline. By including the cultures that we did, we have been able to track the development of the original wheel and concepts associated with it fairly well through the millennia, thus forming a fairly linear (and vertical) timeline. This is warranted instead of a map with a center and lines protruding out from it simply because of the linear progression of the idea. From what we have been able to tell, each successive culture to invent or inherit the wheel added its own refinements and passed it on to the next culture. There was no ‘basic’ wheel that everyone had access to and could refine as they wished, as might be the case with an animal or crop. Accordingly, our timeline is very linear, starting with the basic needs that precipitated the wheel’s invention and ending with the latest innovation within the limits of our chosen time period, that is, ending at 1000 C.E. However, along with the timeline, we also tried to highlight the accomplishments of other cultures who had invented or were aware of the wheel, even if they weren’t a part of the main thread. This led to the inclusion of Mesoamerican and Chinese cultures, along with the Andronovo umbrella of cultures in present-day Russia. We tried to provide some detail as to what each of those cultures did with the wheel or why, in the case of the Mesoamerican civilizations, they didn’t develop it. Raymond Horn, Andy Tisdel, Ian Franks, Bryan Wickliffe