Why does IQ cluster around 100 points?

[Loren Pechtel]

Allow me to rephrase:

You: "Couldn't it be that high IQ people are too socially inept to succeed?"
Me: "If anything, the evidence suggests that high IQ is positively correlated to social intelligence."*
You: "But that's just what I'm saying!"

*To be fair, the correlation, it seems, can only be inferred up to an IQ range of around 120-130. Beyond that, the data is too sparse to make any meaningful conclusions, though some studies suggests that some kind of bifurcation happens, with a bimodal distribution of low and high social competence among extremely high IQ individuals. Also, I seem to have brought that up in a different post.

I'd differentiate social intelligence from crystallized and fluid intelligence, which are two different skills. My point was that the more critical aspect of our neurophysiology is being able to exist in a group, and so our evolution has historically been more about social intelligence, than the kind of mathematical/logical intelligence that IQ measures.

I'd guess that usually 'just enough' mathematical intelligence will do, but having no social intelligence is a non-starter. This re-iterates the point because the vast majority of people are more socially intelligent than mathematically intelligent.

Social intelligence is ultimately how things are sorted out in the real world.

If you can score high on an IQ test but have poor social intelligence, unless you can write or paint or do some other thing that does not require social interaction you will not go far.

The people given opportunity because they have learned and retain superior test taking skills and also have social intelligence can more easily rise to positions of authority.

In a top down society.

Where work places are rigid top down dictatorships.

Social intelligence is good for getting people to do what you want. It's not good for solving problems.

 

[untermensche]

Very few humans solve problems like the questions on an IQ test for a living.

The test has very little real world correlation.

 

[steve_bank]

Social intelligence is ultimately how things are sorted out in the real world.

If you can score high on an IQ test but have poor social intelligence, unless you can write or paint or do some other thing that does not require social interaction you will not go far.

The people given opportunity because they have learned and retain superior test taking skills and also have social intelligence can more easily rise to positions of authority.

In a top down society.

Where work places are rigid top down dictatorships.

Social intelligence is good for getting people to do what you want. It's not good for solving problems.

That is the question that came up around the 70s, the fact that IQ tests do not measure leadership, social, or police potential.

The stereotypical engineer was good objective problem solving but terrible social skills. Not entirely untrue. After Jibs died it came out wile he was a creative genius, he was a horrible manager lacking any people skills. He almost ran Apple into the ground.

Napoleon's military genius was quickly assessing changing battle conditions and adapting. As a long term planner as emporer he was a failure.

 

[untermensche]

People that can score high on an IQ test will randomly have other human traits.

Some will have high social intelligence.

Some will have low social intelligence.

But where you end up in this world depends mostly on where you start.

 

[rousseau]

Social intelligence is ultimately how things are sorted out in the real world.

If you can score high on an IQ test but have poor social intelligence, unless you can write or paint or do some other thing that does not require social interaction you will not go far.

The people given opportunity because they have learned and retain superior test taking skills and also have social intelligence can more easily rise to positions of authority.

In a top down society.

Where work places are rigid top down dictatorships.

Social intelligence is good for getting people to do what you want. It's not good for solving problems.

In some respects I think there can be a tension between the two skills. Consider the CEO who says disingenuous but charismatic things with ease, boosting the morale of everyone except the guy at the back of the room who knows he's full of shit.

To some extent social intelligence is about one's ability to fit in, and to exploit the social dynamics of a group for gain. Where fluid intelligence is about the ability to solve novel problems. Fluid intelligence can be, and often is, applied to social situations, but it also often comes with a desire for fairness, accuracy, and truth. At some point many of those with high fluid intelligence no longer want to sacrifice their integrity for power. Where those with high social intelligence are often less about integrity, more about cohesion and networking.

At best you get a manager with a good mix of both skills, at worst you get a completely dishonest person who snuck into their position.

 

[rousseau]

You are not reading carefully. I didn't say that intelligence has a direct impact on choosing to reproduce. It likely to have an indirect effect on reproductive rates by impacting whether you make decision errors that lead to accidentally getting pregnant without intending to, or by its indirect relation to emotional goals. For example, less intelligent people are more likely to find it too taxing and difficult to reason their way to their own conclusions about most things. Thus, they are more likely to defer to authority, tradition, or social norms to decide what they should do. Since the tradition and social norm is that life is about having kids, people that don't deeply and critically question norms (which takes a lot of mental investment) are more likely to adopt this goal that their life is about having kids and thus will have more kids.

The more I think about it the more it seems like this may be the crux of it.

Literally everything about our biology and cultural norms both tell us that partnering/child rearing is normal and makes steering toward that goal feel good. For those who don't question norms, they'll almost universally aim themselves at having kids. Actually, they won't even be aiming, the'll just be inherently aimed at that goal.

It's like the guy on a mushroom trip who suddenly realizes he can stop playing cards with his friends every Saturday and do something else. In the same way intelligence would act as a catalyst toward the realization that other avenues of action are possible, and maybe even desirable.

So where the brunt of men and women land on the curve likely points to a sweet-spot where people are maximally oriented to want to have kids, and be able to as well.

 

[bilby]

I think you are wrong.

For tens or even hundreds of thousands of years, humans evolved in an environment where it was sufficient for evolutionary and/or reproductive success to enjoy fucking; And to tolerate or even enjoy the raising of any children that happened to come along. But there's not (and never was) any reason to connect the dots between these two things at the genetic level.

Wanting kids is not the same as wanting to raise the kids you happen to produce.

The desire to produce kids is entirely cultural. Evolution led to people with a desire to have sex; In an environment in which people have that desire, there's no selection pressure at all towards a desire to have children. That was true up until the 20th century development of reliable and safe contraception.

Since the deveopment of effective contraception, reproductive rates have fallen below replacement in most places where it is readily available; And they are still falling rapidly and at an accelerating rate. This observation is not compatible with the hypothesis that humans have an evolved or genetic desire for children.

 

[rousseau]

I think you are wrong.

For tens or even hundreds of thousands of years, humans evolved in an environment where it was sufficient for evolutionary and/or reproductive success to enjoy fucking; And to tolerate or even enjoy the raising of any children that happened to come along. But there's not (and never was) any reason to connect the dots between these two things at the genetic level.

Wanting kids is not the same as wanting to raise the kids you happen to produce.

The desire to produce kids is entirely cultural. Evolution led to people with a desire to have sex; In an environment in which people have that desire, there's no selection pressure at all towards a desire to have children. That was true up until the 20th century development of reliable and safe contraception.

Since the deveopment of effective contraception, reproductive rates have fallen below replacement in most places where it is readily available; And they are still falling rapidly and at an accelerating rate. This observation is not compatible with the hypothesis that humans have an evolved or genetic desire for children.

It's not wanting as in 'I dream about making babies all day and night', it's wanting as in 'I know no other way to live my life than to get married/have kids'. Less a 'want' more 'doing what I think I'm supposed to be doing'. Sex and the good feelings associated with a relationship, as well as culture, is the lure, and most people with the means to support kids just get shuttled along that path.

In that frame of reference, it becomes hard not to have kids, unless you are either incompetent, or the type of person who can build a satisfying life outside of stereotypical norms.

 

[bilby]

I think you are wrong.

For tens or even hundreds of thousands of years, humans evolved in an environment where it was sufficient for evolutionary and/or reproductive success to enjoy fucking; And to tolerate or even enjoy the raising of any children that happened to come along. But there's not (and never was) any reason to connect the dots between these two things at the genetic level.

Wanting kids is not the same as wanting to raise the kids you happen to produce.

The desire to produce kids is entirely cultural. Evolution led to people with a desire to have sex; In an environment in which people have that desire, there's no selection pressure at all towards a desire to have children. That was true up until the 20th century development of reliable and safe contraception.

Since the deveopment of effective contraception, reproductive rates have fallen below replacement in most places where it is readily available; And they are still falling rapidly and at an accelerating rate. This observation is not compatible with the hypothesis that humans have an evolved or genetic desire for children.

It's not wanting as in 'I dream about making babies all day and night', it's wanting as in 'I know no other way to live my life than to get married/have kids'. Less a 'want' more 'doing what I think I'm supposed to be doing'. Sex and the good feelings associated with a relationship, as well as culture, is the lure, and most people with the means to support kids just get shuttled along that path.

In that frame of reference, it becomes hard not to have kids, unless you are either incompetent, or the type of person who can build a satisfying life outside of stereotypical norms.

Then why is the fertility rate plummeting, and the number of zero-child families on the rise?

Changes as rapid as those we are seeing can occur due to cultural shifts; But they cannot be due to genetic changes, nor can they occur in phenotypical systems whose primary driver is genetic.

What you are attributing to genes is in fact a rapidly disappearing cultural phenomenon; And the observation that it has not yet completely vanished is not evidence for a genetic basis for that phenomenon.

 

[rousseau]

I think you are wrong.

For tens or even hundreds of thousands of years, humans evolved in an environment where it was sufficient for evolutionary and/or reproductive success to enjoy fucking; And to tolerate or even enjoy the raising of any children that happened to come along. But there's not (and never was) any reason to connect the dots between these two things at the genetic level.

Wanting kids is not the same as wanting to raise the kids you happen to produce.

The desire to produce kids is entirely cultural. Evolution led to people with a desire to have sex; In an environment in which people have that desire, there's no selection pressure at all towards a desire to have children. That was true up until the 20th century development of reliable and safe contraception.

Since the deveopment of effective contraception, reproductive rates have fallen below replacement in most places where it is readily available; And they are still falling rapidly and at an accelerating rate. This observation is not compatible with the hypothesis that humans have an evolved or genetic desire for children.

It's not wanting as in 'I dream about making babies all day and night', it's wanting as in 'I know no other way to live my life than to get married/have kids'. Less a 'want' more 'doing what I think I'm supposed to be doing'. Sex and the good feelings associated with a relationship, as well as culture, is the lure, and most people with the means to support kids just get shuttled along that path.

In that frame of reference, it becomes hard not to have kids, unless you are either incompetent, or the type of person who can build a satisfying life outside of stereotypical norms.

Then why is the fertility rate plummeting, and the number of zero-child families on the rise?

Changes as rapid as those we are seeing can occur due to cultural shifts; But they cannot be due to genetic changes, nor can they occur in phenotypical systems whose primary driver is genetic.

What you are attributing to genes is in fact a rapidly disappearing cultural phenomenon; And the observation that it has not yet completely vanished is not evidence for a genetic basis for that phenomenon.

The fertility rate is plummeting because everyone of my generation is fucked financially, not because the entire nature of human psychology changed in a couple decades.

 

[bilby]

Then why is the fertility rate plummeting, and the number of zero-child families on the rise?

Changes as rapid as those we are seeing can occur due to cultural shifts; But they cannot be due to genetic changes, nor can they occur in phenotypical systems whose primary driver is genetic.

What you are attributing to genes is in fact a rapidly disappearing cultural phenomenon; And the observation that it has not yet completely vanished is not evidence for a genetic basis for that phenomenon.

The fertility rate is plummeting because everyone of my generation is fucked financially, not because the entire nature of human psychology changed in a couple decades.

Being fucked financially was the fundamental condition of pretty much everyone prior to the industrial revolution, and of the vast majority between then and WWII.

Fertility rates are plummeting in plenty of places where people are massively better off than their parents, particularly in the developing world.

That's not an explanation. It's not even an observation - just a local phenomenon in a small part of the world where people have recently been wealthy beyond the dreams of past generations. Sure, the baby boomers have fucked over their descendants. But it's not a global phenomenon - and rapidly declining birth rates are.

Everything we see is consistent with the fact that contraception is a recent phenomenon, and the hypothesis that most people never wanted to have children other than for cultural reasons that are rapidly disappearing.

 

[fromderinside]

Reading.

No that didn't change things.

Contraception.

Now that changed things. Personal observation. Girls couldn't graduate if they were pregnant back in the day. 1960 Graduation class suffered 12% graduation failure due to pregnancy. 1961 Graduation class suffered 0.03% graduation failure due to pregnancy. No. Laws didn't change. The 1961 failure rate does illustrate stupid rates though.

 

[rousseau]

Then why is the fertility rate plummeting, and the number of zero-child families on the rise?

Changes as rapid as those we are seeing can occur due to cultural shifts; But they cannot be due to genetic changes, nor can they occur in phenotypical systems whose primary driver is genetic.

What you are attributing to genes is in fact a rapidly disappearing cultural phenomenon; And the observation that it has not yet completely vanished is not evidence for a genetic basis for that phenomenon.

The fertility rate is plummeting because everyone of my generation is fucked financially, not because the entire nature of human psychology changed in a couple decades.

Being fucked financially was the fundamental condition of pretty much everyone prior to the industrial revolution, and of the vast majority between then and WWII.

Fertility rates are plummeting in plenty of places where people are massively better off than their parents, particularly in the developing world.

That's not an explanation. It's not even an observation - just a local phenomenon in a small part of the world where people have recently been wealthy beyond the dreams of past generations. Sure, the baby boomers have fucked over their descendants. But it's not a global phenomenon - and rapidly declining birth rates are.

Everything we see is consistent with the fact that contraception is a recent phenomenon, and the hypothesis that most people never wanted to have children other than for cultural reasons that are rapidly disappearing.

Fair enough, but even if true you've still misinterpreted my post. Even if contraception is having a fundamental influence on fertility rates and reproduction is entirely cultural, that's still completely in line with the post you're responding to.

It seems like you clung to me using the word 'want', and interpreted it as me thinking people are genetically gung-ho to produce and raise kids. But that's not the meaning I intended. Rather people wanting to fuck and cultural pressure is exactly the type of thing that would lead to people with lower IQs having more babies, which would account for the trend. It's the fact that because of the cultural pressure, and the biologically evolved traits, many can't envision not having kids. It's not that they spend twenty years thinking about the act, it just happens.

 

[bigfield]

It seems like you clung to me using the word 'want', and interpreted it as me thinking people are genetically gung-ho to produce and raise kids. But that's not the meaning I intended. Rather people wanting to fuck and cultural pressure is exactly the type of thing that would lead to people with lower IQs having more babies, which would account for the trend. It's the fact that because of the cultural pressure, and the biologically evolved traits, many can't envision not having kids. It's not that they spend twenty years thinking about the act, it just happens.

I think I understand your theory:

Before contraceptives, everyone wanted to fuck and everyone ended up with babies, whether they were feeling clucky or not. Now everyone still wants to fuck, and many people choose to prevent the babies. Yet for cultural reasons, some people forgo contraceptives. You also think IQ helps decide which choice people make because a high IQ makes a person sceptical of cultural norms.

 

[rousseau]

It seems like you clung to me using the word 'want', and interpreted it as me thinking people are genetically gung-ho to produce and raise kids. But that's not the meaning I intended. Rather people wanting to fuck and cultural pressure is exactly the type of thing that would lead to people with lower IQs having more babies, which would account for the trend. It's the fact that because of the cultural pressure, and the biologically evolved traits, many can't envision not having kids. It's not that they spend twenty years thinking about the act, it just happens.

I think I understand your theory:

Before contraceptives, everyone wanted to fuck and everyone ended up with babies, whether they were feeling clucky or not. Now everyone still wants to fuck, and many people choose to prevent the babies. Yet for cultural reasons, some people forgo contraceptives. You also think IQ helps decide which choice people make because a high IQ makes a person sceptical of cultural norms.

Essentially yes. I think both biology (tendency for sex, lonesomeness, intelligence etc) and culture (heteronormativity normalized everywhere you look) would evolve in such a way to maximize the likelihood that people are oriented to have kids. Those who are intellectually unable to question norms will be more likely to have kids because that's just what people do. Where being able to question norms doesn't guarantee not producing more kids, but it makes it more likely.

This should mean that under a certain point cultural norms should push most people into marriage/parenthood, but where intelligence is clustered is where there is a mix of that and the ability to support kids financially. And after that point more intelligence has a negative or neutral effect on fertility.

 

[Jokodo]

It seems like you clung to me using the word 'want', and interpreted it as me thinking people are genetically gung-ho to produce and raise kids. But that's not the meaning I intended. Rather people wanting to fuck and cultural pressure is exactly the type of thing that would lead to people with lower IQs having more babies, which would account for the trend. It's the fact that because of the cultural pressure, and the biologically evolved traits, many can't envision not having kids. It's not that they spend twenty years thinking about the act, it just happens.

I think I understand your theory:

Before contraceptives, everyone wanted to fuck and everyone ended up with babies, whether they were feeling clucky or not. Now everyone still wants to fuck, and many people choose to prevent the babies. Yet for cultural reasons, some people forgo contraceptives. You also think IQ helps decide which choice people make because a high IQ makes a person sceptical of cultural norms.

Essentially yes. I think both biology (tendency for sex, lonesomeness, intelligence etc) and culture (heteronormativity normalized everywhere you look) would evolve in such a way to maximize the likelihood that people are oriented to have kids. Those who are intellectually unable to question norms will be more likely to have kids because that's just what people do. Where being able to question norms doesn't guarantee not producing more kids, but it makes it more likely.

This should mean that under a certain point cultural norms should push most people into marriage/parenthood, but where intelligence is clustered is where there is a mix of that and the ability to support kids financially. And after that point more intelligence has a negative or neutral effect on fertility.

It might be a plausible evolutionary hypothesis in a universe where humans have been working Office jobs, and had access to modern contraceptives, for many millennia. In ours, not so much.

 

[rousseau]

Essentially yes. I think both biology (tendency for sex, lonesomeness, intelligence etc) and culture (heteronormativity normalized everywhere you look) would evolve in such a way to maximize the likelihood that people are oriented to have kids. Those who are intellectually unable to question norms will be more likely to have kids because that's just what people do. Where being able to question norms doesn't guarantee not producing more kids, but it makes it more likely.

This should mean that under a certain point cultural norms should push most people into marriage/parenthood, but where intelligence is clustered is where there is a mix of that and the ability to support kids financially. And after that point more intelligence has a negative or neutral effect on fertility.

It might be a plausible evolutionary hypothesis in a universe where humans have been working Office jobs, and had access to modern contraceptives, for many millennia. In ours, not so much.

I don't see why contraceptives would need to be essential to the trend. I'm sure people had means of limiting the number of children they had before them, even if the methods were cruder. And even if these methods weren't used, it's still plausible that people of certain characteristics had kids at a higher rate.

 

[bilby]

Rebelliousness need not, and likely does not, correlate with either IQ or reproductive success.

Unless you can show that it does both, your hypothesis is dead. Of course, even if you can show a strong correlation with both, that's only a necessary condition for the success of your hypothesis, and not a sufficient one.

I observe that breaking of cultural norms by poor youths is the starting point of most stories in Western nations, since at least the Middle Ages. The poor farm boy who runs away to seek adventure is typically not driven to do so by intelligence, but rather by naïveté.

The constraints of villiage life provide an opportunity for runaways to have potentially greater numbers of offspring than a stay at home conformist will have.

Your hypothesis doesn't appear to consider the realities of pre-Industrial Revolution life - which was the way of life for the vast majority of human history. Jokodo is right - your hypothesis depends on life having been much the same throughout history as it is today; And we know that to be untrue.

 

[Jokodo]

Essentially yes. I think both biology (tendency for sex, lonesomeness, intelligence etc) and culture (heteronormativity normalized everywhere you look) would evolve in such a way to maximize the likelihood that people are oriented to have kids. Those who are intellectually unable to question norms will be more likely to have kids because that's just what people do. Where being able to question norms doesn't guarantee not producing more kids, but it makes it more likely.

This should mean that under a certain point cultural norms should push most people into marriage/parenthood, but where intelligence is clustered is where there is a mix of that and the ability to support kids financially. And after that point more intelligence has a negative or neutral effect on fertility.

It might be a plausible evolutionary hypothesis in a universe where humans have been working Office jobs, and had access to modern contraceptives, for many millennia. In ours, not so much.

I don't see why contraceptives would need to be essential to the trend. I'm sure people had means of limiting the number of children they had before them, even if the methods were cruder. And even if these methods weren't used, it's still plausible that people of certain characteristics had kids at a higher rate.

It's plausible that "people of certain characteristics had kids at a higher rate".

It is implausible that those characteristics are the same across time and place.

It's not at all plausible we have any chance to glean what those characteristics were by looking at rates of having kids amont late 20th/early 21st century Westerners.

90% of humans ever alive were hunter-gatherers. 95% of the rest were/are peasants. As recently as the 19th century in Europe, and analogously more recently even in other parts of the world, the pre-ordained fate for the first-born son was to inherit the farm, while the pre-ordained fate for all other surviving (male) children was to become a man of the church, or to join an army, or to emigrate to the Americas. Intelligence had very little to do with it, except insofar as an imbecile first-born might be skipped.

What exactly the non-first-born options averaged out in terms of lifetime fecundity highly dependent on local culture, and what if any the interaction with IQ. E.g. in Catholic contexts, becoming a man of the church entailed having no (official) children, while in Orthodox and Protestant contexts, it might mean being the wealthiest man in the village with twice as many surviving children as any farmer. Determining what, if any, intelligence related characteristics have historically lead to having kids at higher/lower rates requires, minimally, determining a weighted average of those local cultural contexts.

 

[fromderinside]

Plausible and implausible can be operationally defined. Please try that since this is a science forum. Then maybe someone can make sense of things.

Oh and I think one can make a strong argument that more than 50% of all humans who have ever lived are not hunter gatherers.

https://www.scientificamerican.com/article/fact-or-fiction-living-outnumber-dead/

All one needs to do is check rates since about 10k years ago when the ratio of farmer or sedentary to migrant or hunter gatherer changed dramatically in favor of those who did not routinely move of hunt. This also corresponds to populations exceeding 250,000 at any one time. Another simplification would be to presume generations are 20 years to reduce the need for continuous change versus longevity given longevity began it's latest increase around the time farming was established. Also presume longevity rose above 50 in 1900.

So although humans minimally have been around for 50k years their populations have only been over 250k for about 10k years. For convenience one can presume 100% before 10k were HG and 100% after 10K were sedentary. Evben if one adjusts for continuous decline in HG to today's about 2% I'm sure that with the as a starting point one can see more later than sooner even though only about 7% of all humans are alive now. I leave calculation to those who really need to do such things.