The idea, culminating here:
Is that the 'dysgenics' discourse may have been focusing on the wrong topic - too much focus on fertility, and neglect
Natural selection depends on both fertility/ birth rates and mortality/ death rates. Babies are born, but reproductive success depends on how many of these babies reach sexual maturity and live long enough to have offspring.
Those interested in dysgenics have focused on the fact that the less intelligent (and those with less socially desirable personality traits) are more fertile than the more intelligent and more conscientious, self-controlled and altruistic.
But the primary fact is, I believe, reduced mortality - the situation that since 1800, more and more of the babies that are born will live to have offspring.
Every new baby is likely to have one or two new spontaneous deleterious gene mutations - some lethal, some only mildly harmful and others in between - they may also inherit mutations from their parents.
Why doesn't this genetic damage mount up, generation upon generation, to overwhelm and destroy the fitness of the species?
Essentially, under 'natural conditions' because the mutations are filtered-out by high child mortality rates.
Through most of evolutionary history, most babies and children (probably a large majority of them) especially those with the worst genetic damage - have died before reproducing. Thus mutation load is filtered by differential child mortality rates with each generation.
Those who have the least genetic damage are the healthiest and best adapted, and only they will (on average) be the parents of the next generation.
If it is correct that - up to about 1800 - in almost all situations almost all babies died (and maybe only the 'fittest' 15 percent or so survived - or the fittest thirty percent... the exact number makes little difference).
But since 1800, starting in England then incrementally spreading across the whole world with no exceptions, child mortality rates have got lower, and lower; the mutation filtering effect has got less and less complete - and the mutation load has got greater with each generation.
This must have happened. The only question is how much?
So, the primary mechanism of dysgenic change is mutation accumulation. But this is where more usual dysgenic topic of differential fertility comes in.
Theoretical calculations suggest that the effect of mutation accumulation under these circumstances would be quite slow - IF normal natural selection was in play and higher levels of mutation accumulation led to lower fertility.
But in the modern world, the direction of natural selection has reversed. In the modern world, higher levels of mutation accumulation lead to higher fertility (so long as the mutations are sub-lethal).
In historical times, natural selection filtered-out mutations; but in the modern world natural selection amplifies the carriers of damaging mutations!
(Up to a point, where pathology more-or-less prevents reproduction), the carriers of accumulated deleterious mutations ('mutants') - probably both between and also within populations, have the highest fitness, on average.
Indeed, in the modern world, natural selection actually filters-out undamaged genomes - since the people with the least damaged genomes are least likely to have offspring.
The best genetic specimens have sub-replacement fertility - the (ever fewer) least damaged genomes are being actively eliminated by reproductive choices: this applies especially to women more than men.
The above is why things are happening so very fast - e.g. why general intelligence is declining so rapidly (as revealed by simple reaction time slowing).
What is now needed is to gather more data to measure the long term rate of mutation accumulation.
I think that the cure will be worse than the disease. To cure it would involve allowing infant mortality rates to rise through withholding medical treatment or filtering for genetic mutation to abort fetuses or imposing sterilization on those with genetic mutations that are deemed dysgenic.
And who gets to make this decision, and enforce it?
In other words we are stuck with it, because the cure is unacceptable.
@NF - Agree. We just have to make the best of things. But it is helpful to know what has been going on and will continue - for a while. Of course, in the end, 'normal service will be resumed' whatever we try to do.
When the dam finally bursts, nature's cure will indeed be worse than the disease.
Violent crime overflowing out of swelling inner cities provides a preview of the coming cataclysm.
Look inside maximum security prisons for an even more vivid preview of life to come in the suburbs and deluxe flats.
Be nice and pretend it isn't building to a climax.
@AF - Violence is one possibility - the others are disease and starvation. Or mixtures. But I strongly doubt if things would be the same everywhere. In premodern times, it seems that population in East Asia was held in check by starvation mostly, in Africa by disease mainly, plus violence; in England - where records are the best, we can see starvation leading up to the Black Death and loss of half the population - then a change in the balance with less starvation for about three hundred years.
up to about 1800 - in almost all situations almost all babies died (and maybe only the 'fittest' 15 percent or so survived - or the fittest thirty percent
Are you quite sure this is accurate? It's so staggering when you present it like this... The average person never had adult children?
@SJ - yes, that's it. This comes through in detailed specific instances.
For example, the Kalahari Bushman woman Nisa interviewed by Shostack had six children - all of whom died.
FROM A COMMENT FROM JEFF - "Jeff has left a new comment on your post "Dysgenics is *mostly* due to reduced childhood mor...":
"How confident are you that the reduction in the intelligence of whites is due to mutation load and not some type of environmental phenomena induced by diversity, easy money and globalism? Maybe the data reflect changes to behavior based upon environment? Put a lot of rats in a cage and they are different than when the population is lower. "
The evidence for mutation load is the fact of slowing of reaction times, that this slowing is too rapid to account for from differential fertility; plus the body of evidence from history and theoretical biology - but I would like more!
Alternative suggestions have to have some plausibility as a cause of intelligence changes or reaction time changes - these environmental factors don't make any real difference to general intelligence - it is a very robust phenomenon or else it could not be so predictive.
In the modern world, higher levels of mutation accumulation lead to higher fertility (so long as the mutations are sub-lethal).
In historical times, natural selection filtered-out mutations; but in the modern world natural selection amplifies the carriers of damaging mutations.
Yes, and as concisely, cogently, forthrightly, succinctly portrayed in the opening two minutes of this PBS documentary.
@ls - Actually Idiocracy posits the mechanism on differential reproduction - high, above replacement fertility of the least intelligent; combined with sub-replacement fertility among the most intelligent.
I am saying this is the secondary mechanism - and that the primary mechanism of 'Idiocracy' is mutation accumulation due to near zero mortality rates.
I'm sorry to say that the probable scenario of mutation accumulation is a much more pessimistic view than the one depicted in Idiocracy...
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