Lately there has been some debate between Dr. bloggers questioning whether evolution selects more for reproduction or longevtiy and its impact on the optimum diet. Some have stated that evolution selects for reproduction not longevity because genes don't care about living past their reproduction, so to speak. Others have argued that evolution may select for longevity because of the contribution of people beyond child bearing years to feeding and educating children.
This http://www.sciencedaily.com/releases/2012/10/121023204142.htm is an interesting simulation of the impact of grandmothers on reproduction and evolution. The simulation seems to indicate that humans may have significantly longer post-childbearing lifespans, than other primates, because of grandmother's help in feeding children post-weaning, allowing younger women to have more children. By allowing mothers to have more children the odds of early women with long longevity passing on their genetic advantage was increased.
I believe that there is was selection pressure for longevity.
What do you guys think of the grandmother hypothesis? Does it make you think about changing your diet at all? How?