Additional to the effect of parental investment on the selection pressure favoring longer lives (and thus a lower rate of aging) in humans, is potentially the effect of grand-parental investment. If in humans grandparents have a large impact on the rate of survival and reproduction* in their grandchildren, then the selection pressure for survival gets pushed to even higher ages, potentially into the ~60′s/70s. The importance of grandparents seems to be relatively unique to humans.
I’ve seen enough evidence (related to the grandmother hypothesis wrt. the evolution of menopause in women) that at least grandmothers still invest heavily and effectively in their grandchildren that this is a plausible mechanism leading to longer lifespans in humans. For instance, survival rates of children with grandmothers in hunter-gatherer societies have been measured to be greater than for those without.
I do wonder if this should lead us to think that aging should be faster in men than women, though given that we all have both a mother and a father, that speculation isn’t entirely obvious to me.
*the importance of things like status and skill transfer in humans means that beyond just influencing survival grandparents might also influence the reproduction rate in their descendants in other meaningful ways.
Additional to the effect of parental investment on the selection pressure favoring longer lives (and thus a lower rate of aging) in humans, is potentially the effect of grand-parental investment. If in humans grandparents have a large impact on the rate of survival and reproduction* in their grandchildren, then the selection pressure for survival gets pushed to even higher ages, potentially into the ~60′s/70s. The importance of grandparents seems to be relatively unique to humans.
I’ve seen enough evidence (related to the grandmother hypothesis wrt. the evolution of menopause in women) that at least grandmothers still invest heavily and effectively in their grandchildren that this is a plausible mechanism leading to longer lifespans in humans. For instance, survival rates of children with grandmothers in hunter-gatherer societies have been measured to be greater than for those without.
I do wonder if this should lead us to think that aging should be faster in men than women, though given that we all have both a mother and a father, that speculation isn’t entirely obvious to me.
*the importance of things like status and skill transfer in humans means that beyond just influencing survival grandparents might also influence the reproduction rate in their descendants in other meaningful ways.