Research shows a reasonably high correlation(not causation mind you) between intelligence(IQ), education and wealth on average. Studies also show that there is an inverse correlation between education & wealth and the number of children that people have - i.e more educated, richer people are more likely on average to have fewer children. (I don’t think these are controversial points, but in case people think so, I can provide cites)
My question is as follows - Intelligence was the main trait that set us apart from other apes. With time(evolutionary time scales), intelligence got selected for and aided in the survival and spread of the human species and we became more and more intelligent. In today’s world (and hopefully tomorrow’s), societies guarantee at least the survival of all, especially in the developed world. If more intelligent people are having fewer kids, and less intelligent people are having more, and both sets are equally likely to survive and reproduce (this last is an assumption of course, but not wholly unrealistic I think?) will we see humankind on average become less intelligent, or at least a reduction in the rate of growth of intelligence?
Please note: This contention is value neutral, I’m not implying that intelligent = good, not intelligent = bad
I would say that the OP owes Mike Judge royalties if it weren’t for the fact that the old, worn out cry of “only stupid people are breeding” (to borrow from the even earlier Harvey Danger) wasn’t already worn out even by the time Idiocracry came out.
snarkiness aside…it is valid question. You may not LIKE the question, but it is still a valid question.
My thoughts, and this is just pulled from my nether regions, is that humans have NOT been getting more intelligent. There was probably a huge ‘bang’ in the past where humans acheived or came really close to their current intelligence and then has been drifting ever since. Take a ‘caveman’ baby from his mother and raise him today and you probably wouldn’t see a difference.
If that is so, then humans will probably continue to drift at about the same intelligence. Having more people survive I don’t think means we get more dumb.
I think Cyril Kornbluth first covered this problem in “Marching Morons” in 1951. Or maybe it was H G Wells in “The Time Traveller”.
One of the problems is that any social organization selects for non-survival traits. People whose vision is too poor to hunt and gather or avoid sabretooths continue to function well. People with diabetes, weaker immune systems, defective organs, often live long enough to pass on those genes. Intelligence is just one of the traits that is not being selected for.
Except, in any social situation, perhaps to some extent intelligence is being selected for or at least, lack of intelligence is being negatively selected. Take the example of the fellow I heard about from the local high school (I believe he dropped out, despite the ease of graduating nowadays). A friend’s son mentioned him because he had knocked up a 4th or 5th girl by the age of 20. (not sure how many of them went on to finish the reproduction process). There’s got to be some level of intelligence on his part to talk some girl into unsafe sex when they know in the small town he’s already knocked up a handful and walked out on them.
Or are we selecting for clever guys and really dumb girls?
I think C.M. Kornbluth may have been the first to use this idea.
But I think the central premise is questionable. It’s not just a question of comparing birth rates. The reason some societies have such high birth rates is to compensate for having such high childhood mortality rates. People used to have eight or nine kids so that they could have a reasonable expectation that two or three of them would grow old enough to have kids of their own.
Modern health practices have reduced the childhood mortality rate but similar factors may still apply. Intelligent people may have fewer children but their children are probably more likely to grow up healthy and well-educated and will be more likely to have families of their own. You might find that intelligent people have fewer children but end up having more grandchildren.
We should distinguish between intelligence potential and intelligence potential actualization.
Do most people who have above average IQs have them because of a higher potential or do they have roughly the same potential as lower IQ people but have actualized it to a greater extent?
If it’s a question of potential, then yes, it seems that the average IQ would get lower if lower IQ people have more children and that those children in turn produce more offspring.
If higher IQ people have it largely because of the actualization of their potential more than their potential, then the increase in education (broadly construed) would result in average intelligence going up, not down.
To take a less controversial example than intelligence, let’s look at height: Physical size was a greater advantage in the past than it is now. In the past few centuries, height potential hasn’t really had the time to change much. Yet average height has gone up because its potential is more fully realized than it used to be.
The correlation between intelligence and wealth has not been shown to be genetic. It follows families mostly to the extent that wealth follows families. It’s entirely likely that wealthy people have [whatever factor] that lets them maximize their genetic potential for intelligence. If that’s true, then boosting average intelligence is as simple as boosting average wealth. And, it makes no difference who has the kids.
Even if we postulate that intelligence is genetic, I think you’re likely to wind up with divergent populations, given that the wealthy do not generally marry the poor. Thus, the smarter population continues to get smarter even if the average goes down. In a technological world, it’s really the intelligence of your top few that is most important. (For example, it takes an engineer to design a car, but any idiot can drive it.) It might be nice to have a large pool of geniuses rather than a small one, but even our small pool is going to be hundreds of millions strong.
I never claimed it was an original idea. Merely that I would like an answer.
Thanks(will also check out Kornbluth 
The central premise that you are questioning is that both sets(intelligent and not) are not as likely to reproduce and/or survive. I readily admit this was an assumption on my part, but I thought it a fairly true to life. Is there good reason to believe that less intelligent people will, on average? , not go on to reproduce or have fewer grandchildren?
I hope intelligence IS selected against. Intelligence is what caused/is continuing to cause the destruction of the world.
Intelligence doesn’t mean what you think/do is right or more valid or is the best coarse of action, it just means you have more brain cells. Too much intelligence in one species is a plague on the earth, and I would be happy if all humans got wiped from the earth and allowed our relatives the other great apes and other life like ours to continue on in peace.
I think most people would list intelligence as a desirable trait in a mate. And intelligence is also correlated with other desirable traits like economic success, social standing, and good health. So intelligent people have better mating prospects.
On the other side, stupid people make stupid decisions. And sometimes that leads to people winning a Darwin Award.
The correlation between intelligence and wealth - genetic? Are you saying an intelligent family may become poor and thus their children revert to a higher fertility rate? That is a possibility. Just not sure if it would affect the average.
Your second point could be valid as well, especially given research that college graduates overwhelmingly tend to marry other college grads. Wouldn’t this smarter population dwindle though, especially if the fertility rates are below the replacement rate at 2.1 (which they are for many rich and highly educated countries)?
I pretty much agree with dracoi’s point, that even if on average humans are getting dumber because dumb people breed more often (a point I probably don’t disagree with, but which I would not ardently support), the more intelligent class typically inter-breed with one another and are most likely producing smarter and smarter offspring. There will always be enough of these super smart people around to lead scientific advancement, etc, so we really have no reason to be worried.
Name+post combo of the thread!
Remember, change starts with you.
Talk’s cheap. What have you done as an individual to reduce the number of humans on the planet?
Considering in the fifty-odd years of history that the posters above have outlined (in fact, the idea — if we can privilege the thought “Look at all these dopes making babies”* with the name “idea” — is much older than a mere fifty years) have also witnessed some of the most remarkable progress in science and technology in human history, what do you suppose the answer is?
- Although you ape clinical terminology by talking about correlations, you make no effort at all to eliminate any confounding variables. Your premises of a general co-occurrence of intelligence, education, and wealth and a general co-occurence of low-wealth, low-education, and fecundity do not at all establish any relation between intelligence and fecundity. Nor does it even attempt to incorporate the role of cultural norms for family size. So, in short, although you will resist the characterization that all your OP amounts to is “Look at all these dopes making babies,” that is, in fact, all you’ve come to the table with.
Oh there’s little doubt in my mind that intelligent people have better mating prospects (although I would have been hard pressed to see this in high school) It’s just that I think that means you’ll get a better mate, not have more children.
Also, the Darwins rock One wonders if that segment is large enough to make a difference though…
Hmm. I apologise if I’ve upset you in any way. That was not at all my intention. This is merely something I wonder about and I hoped to get an answer, and this seemed like a good place to get it. If we can agree that I might actually just be trying to fight my own ignorance, I’ll be quite happy to address your points respectfully and hope you will consider doing the same in return. This can so quickly devolve into something unhelpful otherwise don’t you think? What do you say?
I used to worry about such things, then I decided that we will probably be the last generation that will be stuck with genes that chance happens to give us. A more interesting question will be what happens if genetic selection is restricted to the wealthy and well-to-done. Imagine if they can stack the deck so that all their children are the genetic equivalent of a straight flush. Not mutants, but optimal children.
Not really hard to imagine, when cheap ultrasounds are limiting the production of girl babies in some countries.
Fewer than whom? Are you comparing birthrates within individual societies or between them?
Sure, there are lots of poor people in third-world countries having lots of children. But I doubt that the intelligence/wealth correlation is exactly the same in third-world countries as in developed countries. You can’t just make the assumption “lower wealth correlates with lower intelligence” across the board worldwide, even if it may be true for certain local populations.
I also wonder how we can draw any definite conclusions about the heritability of intelligence if we don’t understand its specific genetic factors. Sure, on average smarter parents tend to have smarter children and dumber parents tend to have dumber children, but how uncommon is it to find a smart kid from a dumb family or a dumb kid from a smart family? If individual variation frequently exceeds average differences between groups, isn’t that basically all it takes to keep the gene pools a-mixin’?
And finally, if such selective pressures do have a noticeable effect on populations, then I wonder why they don’t seem to have made humans more beautiful on average over time. Sure, we have modern medical advances that have given modern humans better nutrition and better dental care and various medical treatments, but those are all improvements in nurture, not genes. Genetically speaking, the average crowd of people that you see in the street today doesn’t seem significantly, intrinsically more endowed with physical beauty than the average crowd you see in a painting from four hundred years ago. But since we know that human sexual selection favors physical beauty, why haven’t we as a species become fundamentally much better-looking?
The tentative answers seem to be more or less the same for beauty as for intelligence:
Speculation 1) Other factors play enough of a role in reproduction that [beauty/intelligence] isn’t decisive when it comes to selecting mates.
Speculation 2) Random individual genetic variations from [ugly/dumb] or [beautiful/smart] parents to [beautiful/smart] or [ugly/dumb] offspring are large enough and frequent enough to overwhelm average differences between groups, so populations don’t end up self-isolating.
Speculation 3) So many factors, both genetic and environmental, affect the realization of [beauty/intelligence] potential in any individual that it’s very hard to track genetic trends involving these characteristics.
I think the OP is overstating the extent of our knowledge about what intelligence is, how it is inherited, and whether or not we have a “growth” of intelligence now (or had one in the recent past).
In short, there is no factual answer to your question within the scope of our present knowledge.