Geoffrey Purcell wrote:
  35 for men and 30 for women was
> merely the mean average lifespan and took into account a very high
> infant mortality, 


It [i]is[/i] the age of maturity, after which age-at-death is dated by 
examination of marks of disease on bones.
We (neolithic man) all have these; the bones of paleolithic man do not 
have marks of disease.
This is why we try to eat a paleolithic diet, so that we don't have any 
of the diseases that leave such marks on bones.

The idea that no disease = death is a stupid idea.

William