I would like to make one other observation and it is not my intention to offend anyone. I see the recent interest with prehistory and the future as signs of retreat. I am not a historian and history per se, as recording, recounting and reinterpreting past events is as interesting and relevant for me as scholastic philosophy and debates about the number of angels which could dance on the head of a pin. This is not to say that history is irrelevant, History is eminently relevant insofar as it enables us to understand the genesis of the trends which have shaped the present and are shaping the future.
History is sued to reveal the origin and genesis of the trends shaping the present.
I am however, hard pressed to see how extending the time line back 3 or 4000 years and expanding the scope eastward and westward fulfills this function.