It stands to reason that postponing reproduction for as long as reasonably possible would contribute to selection for longevity. From evolution's perspective, you have to survive at least that long, or else you're not good for anything. If humanity collectively decides to postpone having children, evolution may begrudgingly allocate more of its resources toward the welfare of individuals, rather than viewing our early deaths as an acceptable loss in a cold utilitarian calculation about long-term gene proliferation.
(edits)
You could imagine a graph showing the percentage of pregnancies that occur at each age. The strategy would be to gradually move the percentages over time so that some percentage of sixteen year old pregnancies get shifted over into seventeen year old pregnancies, some seventeen year old pregnancies become eighteen year old pregnancies, and so on.
The goal is that, over time, there is escalating pressure to solve health problems that occur at later ages, problems that evolution currently has little incentive to address.
But dows that mean some sort of Lamarckian evolution is taking place after all?
Sexy son hypothesis is also similar. Is it related?
There is (at least for women).
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4270889/
> A significant association for later maternal age was found whereby women who had their last child beyond the age of 33 years had twice the odds of survival to the top 5th percentile of survival of their birth cohorts compared to women who had their last child by age 29 (OR=2.08, 95%CI 1.13; 3.92 for age between 33 and 37 years and OR=1.92, 95% CI 1.03; 3.68 for older age).
It's important to know though that delaying childbirth among women is associated with all sorts of other "healthy" factors like high education, high income, stable marriage, etc.
https://www.ncbi.nlm.nih.gov/m/pubmed/16510865/
But this study is contradicted by many studies
https://www.scientificamerican.com/article/having-sons-can-s...
Do children at 20-30 increase or decrease life span?
Obviously people who live longer may have more children, especially the men. I am talking about the other way.
Sometimes it's good sometimes it's bad. ¯\_(ツ)_/¯
As people live longer and safer lives, they can afford to have children later. And child mortality has been seriously reduced, so the children they have are comparable to thise among people from previous centuries who had many children younger.
Having children takes a toll on an organism, and having many children takes a larger toll, presumably. I wouldn't be surprised if there is a correlation between lifespan and number of children, among women.
So - people live longer and have children later. The children grow up richer and bigger and in turn have children later, as well.
I bet there is a correlation between age of having children and lifespan.