4 ms·
> Humans are the only species where the grandmother hypothesis is supported by data, but the dearth of corresponding data in whales suggests the dramatic dispar
by maaku 13y ago
> Humans are the only species where the grandmother hypothesis is supported by data, but the dearth of corresponding data in whales suggests the dramatic disparity in our somatic-reproductive senescence might be more strongly selected for by factors we are not yet aware of.
I thought average life expectancy of per-agrecultural, pre-technological humans was less than 40 years? It doesn't really seem like the grandmother hypothosis would enter into our evolutionary history then, as there would be very few post-menopause grandmothers around...
- jeorgun 13y agoAverage life expectancy is calculated without accounting for infant mortality; when accounted for, it's considerably higher, or so I'm told.
- crpatino 13y agoEven if infant mortality is discarded, average life expectancy is a poor estimator of typical expectations of life. Considering the case of pre-industrial societies, there was a second big wave of mortality during what we now call adolescence. In women it was driven by child bearing, while in men by either accidents or armed conflict with other groups of men. If half of the guys that make it to their 13th birthday will get themselves killed before their 21st, an average of 40 y.o. gives a very misleading idea of what "old folks" look like.
- CWuestefeld 13y agoaverage life expectancy Age at death has a bimodal distribution: a huge portion of humans die at or near birth. If you survive that you're pretty likely to live quite a while, living well past the mean. That's 'cause all the deaths at infancy bring down the mean quite a bit.
- gnaritas 13y ago> I thought average life expectancy of per-agrecultural, pre-technological humans was less than 40 years? Bill Gates fortune and mine average about 33 billion; averages aren't always useful information.