> >think an active wild human, doing those things that wild humans do, and > >eating the wild human diet (paleo) might not run into so many back and > >neck problems. > > Exactly what I think also. There are so many cases where they blame > "unsufficient" evolution for problems which are actually due to modern > lifestyle. > > - Hans I had a thought looking at this. Usually, people think of evolution as a thoughtless, automated process which takes only one simple equation into account: How successful is gene X at leaving descendants? But there is a way that thought can get mixed into this process: Sexual selection. If the choice of a mate has ever hinged on whether she or he looks and acts healthy (and having a endlessly sore back would not count as healthy), then the process of sexual selection would accelerate the process by which the tree-dweller back would adapt to a biped back. I wish there were some way of estimating how long it would take to adapt to a specific environmental change. Erik