zlacker

Shouldn't kids with grandfathers have an evolutionary advantage?

>>jbd0+(OP)
when humans were still primarily subjected to natural selection the life expectancy likely wouldn't have allowed for many grandfathers.

>>jbd0+(OP)
They didn't say drops to zero, but the advantage is obviously more limited

>>natebc+15
You only have to live to your 40s to become a grandparent in natural conditions, and your chances of living to at least your 50s have always been pretty good conditional on living long enough to reproduce at all.

>>natebc+15
Iirc, historically, if you made it to 10 years of age, most humans make it to 60

>>jbd0+(OP)
If it wasn’t in the past, I imagine it will be in the future with how common two working parents is now. We want more kids but we are getting zero grandparent help

>>jbd0+(OP)
Probably barely, and I think in some instances the opposite. You have to care for the elderly.

>>readth+es
Medieval burial grounds, when examined by anthropologists, do contain some people over 60, but the majority of adults buried there died earlier, typically in the 45-55 bracket.

It wasn't just disease, but also wars and famines. And in women, deaths during childbirth, which cluster in the 20-35 bracket.

Cardinals of the Church, who led peaceful lives, didn't give birth and never went hungry, lived into their late 60s and early 70s even during the Middle Ages. But an average peasant wouldn't.

>>jbd0+(OP)
The problem there is with your definition of grandfather. Currently, the age for a grandfather in developed countries is 55+. For most of humanity's history, if there were grandfathers, they would barely make it to 55 years of age.

>>Izikie+rv1
No, plenty of people made it to that age in the past. Life expectancy was significantly depressed by infant mortality.

>>saagar+2z1
> in the past

What's "in the past" here? Last 200 years? 500? 1000? In evolutionary scale, those numbers are a blip.

>>george+lA
Two working parents have far below replacement numbers of children, so it would actually cause it to disappear…

>>Sharli+Nk
Your 40s? A man could pretty easily be a grandfather at 26-28, possibly less.

Perhaps less common but 30s would probably be more likely.

>>jbd0+(OP)
The grandmother hypothesis https://en.wikipedia.org/wiki/Grandmother_hypothesis is reasonably well-established. The corresponding 'grandfather effect' has not really been demonstrated, as far as I know. https://royalsocietypublishing.org/doi/pdf/10.1098/rspb.2007...

>>const_+AN
Grandparents used to be 40ish when their grandchildren were born.

>>jbd0+(OP)
Probably improved more with lots of siblings from a wide age range. The bigger siblings would do productive work, the younger would take care of the little ones.