Todd has some real good points. There are many avenues of research available
to us as to the best diet for humans. In other animal species, the "speed"
of adaption has been shown to be sometimes very fast. Birds are a good
example. A couple of years ago in Oklahoma there was a large die-off of Bank
Swallows following a cold rainy period in the spring. Those that died were
less symetrical than those that lived - natural selection in real time.
Humans seem to be much more adaptable to climate and food types than Bank
Swallows. It seems reasonable to me that, considering the length of time
humans have been eating food quite different from that of our African
ancestors, that we, too, may adapt more rapidly than is usually thought. I
read somewhere that nearly one quarter of the human population is well
adapted to grains and lacks the problems that the majority of us have.
Tom Barber