> In the former case, parents choosing between 10 or so zygotes could improve the IQ of their child by 15 or more IQ points.
Well, yes—if you kill the bottom 90-93% of people ranked by intelligence, then the remainder are going to be quite smart.
Of course, that doesn't account for the possibility that there might be other good things about the children the parents never see.
And in fact, if it's true that there's a strong correlation between high intelligence and problems, then such an approach might lead to more problems than it solves.
Artificial selection also appears to work in unusual ways. We don't really understand the mechanics of it. Foxes were selectively bred in several experiments (and for the fur trade) for tameness. Basically breeding only foxes that don't bite or recoil from people.
The breed developed a whole range of dog like characteristic, behavioral and morphological. They whine and bark (which neither wolves or wild foxes do). They develop a diversity of coloration. I've even heard some had cute floppy ears. Obviously there is a corollary to dog evolution, which we don't really understand either.
Selecting for a trait or a family of traits in humans will probably have unexpected side effects.
Yeah, the domestication of the silver fox is one of those really cool stories but also—to someone as astute as you—is a bit of a cautionary tale about unintended consequences.
> s a bit of a cautionary tale about unintended consequences.
There was nothing unintended about it: the original hypothesis was to see if those changes were interconnected as they seemed to be in various domesticated animals.
The effect of domestication was large enough to be observed, one might say, with the naked eye. As I keep asking in this page in response to all the groundless fearmongering: do we observe, with the naked eye, huge increases in pathologies of various sorts with people of extremely high intelligence? Or do we observe only some small increases in some problems and also indications of net benefits like increased longevity?
Well, yes—if you kill the bottom 90-93% of people ranked by intelligence, then the remainder are going to be quite smart.
Of course, that doesn't account for the possibility that there might be other good things about the children the parents never see.
And in fact, if it's true that there's a strong correlation between high intelligence and problems, then such an approach might lead to more problems than it solves.