Evolution

I recommend you pick up the August 25, 2003 special edition of Scientific American entitled "New Look at Human Evolution". It may be a bit dated since it is 5 years old, but there are many very well written articles on evolution.

In the first article by Kate Wong, entitled "An Ancestor to Call Our Own", Dr. C. Owen Lovejoy of Kent State University makes an interesting comment as to the debunking of the theory that hominids came to walk upright once they relocated in the African savanna. I reproduce here the small paragraph wherein it is found:

"...climate change may not have played as important a role in driving our ancestors from four legs to two as has been thought. For his part, Lovejoy observes that a number of the savanna-based hypotheses focusing on posture were not especially well conceived to begin with. 'If your eyes were in your toes, you could stand on your hands all day and look over tall grass, but you'd never evolve into a hand-walker,' he jokes. In other words, selection for upright posture alone would not, in his view, have led to bipedal locomotion. The most plausible explanation for the emergence of bipedalism, Lovejoy says, is that it freed the hands and allowed males to collect extra food with which to woo mates. In this model, which he developed in the 1980s, females who chose good providers could devote more energy to child rearing, thereby maximizing their reproductive success."