True. My SO is the eldest of 12, all singletons, born in Milwaukee in the 50’s and 60’s and 70’s. And his folks weren’t even Catholic! His mom lived to 87 before small cell lung cancer did her in. Her eyesight was gone years before, but she was constitutionally sound as an ox until the cancer in her late '80s.
Of course, as we all know, anecdotes are not the same as data, and Lynn is of course right that having lots of babies in close proximity does increase the chances of something going wrong or mom just wearing out or her fertility taking a nosedive. But the OP doesn’t need to worry about chances - he’s just got one woman to deal with. One women can certainly have babies into the double digits.
“Wright’s Inbreeding Coefficient” is a way to quantify inbreeding. When half-siblings marry, their offspring have coefficient 1/8 (meaning they have 1/8 chance of inheriting the same autosomal allele from their common ancestor).
And, in OP’s scenario, the coefficient remains at 1/8 as generations go by. This is logical: For the 3rd generation all 4 gt-grandmothers are the same person; for the 4th generation all 8 gt-gt-grandmothers are the same, etc.
As rachelellogram agrees, this is the optimal solution. Just doing this at generation 2 drops Wright’ coefficient down to 1/32, I think.
@WhyNot: I know, I probably am overthinking it. Was trying to figure out what baby-momma would have to look at in the first few generations she’d be alive - because of course she’d be encouraging breeding early (hairlip issues, malformed children, etc).
@Septimus: Thank you! That’s a really good article and I hadn’t come across it just yet.
@The general group: I’m also looking at how long sperm can be kept frozen & viable to deal with some of these issues without it becoming too far-fetched. I do appreciate all the input as it helps to flesh some ideas how that I’m unfamiliar with.
I suggested terminating the first generation males. But maybe “termination” is too unpalatable a term. How about “avoiding”? Filtering out? Selecting against?
With this scenario, you have the fate of the entire human race at stake, so you want to make as few mistakes as possible and cost is not an issue.
So in-vitro fertilization would almost certainly be demanded and only female embryos should be implanted.
Why? Because as it was suggested earlier, the first generation male offspring should not mate at all. If the calamity is not age-selective, there will be plenty of male children who are not related to Eve. So why waste Eve’s precious gestation slots with baby boys that can never mate with their sisters?
There are also other sites that say that women need some time between pregnancies to rebuild their reserves of iron and folate. So, while it’s POSSIBLE for a woman to have a baby every 10 or 12 months, it’s really not advisable, even if she’s trying to repopulate the planet as the sole female parent.
There’s also the issue of one parent taking care of multiple small children. Even if we allow Eve only one year to recover, she’s going to have a toddler in the Terrible Twos when she’s nursing an infant, and both of them in diapers. At least one daddy needs to pitch in and help with the child care, or Eve might very well strangle some of her offspring. It’s true, when kids get older, they CAN pitch in. And let’s note that Michelle Duggar pops out a baby about every 18 months, and then hands it over to an older sibling for most of its day-to-day care.
“Associated with increased risk” could very well be speaking in terms of single-digit increases in percentages. Your cites do not back you up very well. And no one is arguing whether it’s “advisable” or not.