I've been on a no refined sugar diet the past week and as a result I've been eating more fruit. Today I was eating an apple and thought about how it was one of natures best source of sugar, or energy. It was interesting to me how this rich source of energy was available mostly to tree dwellers.
Looking into it I found that foliovores (leaf eaters) have a smaller brain to body ratio than frugivores (fruit eaters). Perhaps early primates' access to trees and the fruit they provide lowered the amount of work needed to eat, freeing time, and perhaps able to provide more energy to the brain.
If this is true, it is interesting that in the bible chose fruit to be the source of knowledge in the garden of Eden. Perhaps some philosopher long ago had this theory and it worked it's way into Genesis. One can look at the fruit as a catalyst for the evolution of intelligence among primates.
Perhaps Genesis is the remnants of some forgotten knowledge. The are other things about Genesis that have piqued my imagination in the past. "Now the earth was formless and empty" this can be a description of the early universe which contained nothing but hydrogen. Next "And God said, Let there be light, and there was light." which follows what we now know of the natural progression of the universe, stars formed from the hydrogen creating light for the first time.
"Then God said, Let the land produce vegetation: seed-bearing plants and trees on the land that bear fruit with seed in it, according to their various kinds. " can be seen as a metaphor for the first spark of life, which was created from the elements and chemicals of the Earth.
God also created life in the oceans first, again supported with current scientific theory. Men today, are almost identical with the people that existed one hundred thousand years ago. There would have been Einstein and Newton level intelligence. Unfortunately writing would not come until much later in our history, but perhaps some of that knowledge got caught in creation myths that were passed down orally for generations until Genesis was written down.
Here is a Harvard paper with some interesting foraging hypothesis: http://www.hcs.harvard.edu/~hsmbb/BRAIN/vol2/Primate.html