“It is a common experience that a problem difficult at night is resolved in the morning after the committee of sleep has worked on it.”
See if you still envision our hunter-gatherer ancestors as knuckle-dragging simpletons after reading this article from UK’s The Daily Mail, Online. What an amazing discovery. This should really fuel the fire of the “agriculture as a necessary precursor of advanced civilization” debate. This collection of “heathens” seemed to be doing pretty well for themselves. They apparently even had time to develop some fairly advanced artisans, as evidenced by this picture (from the above-linked article):
Just goes to show how little we do know about the past. Other than the construction of a proper diet, I wonder what other wisdom has been lost over the millennia?
In Health,
Keith
Theory to Practice 
One thing that I forgot to add in this post was that some of this artwork — especially the lizard/alligator thingy depicted in one of the article photos, looks strangely like Mayan art. Things that make ya go, Hmmmm.