Would the clones be at least as smart as the original? On the yes side we have the Flynn Effect, which is the steady increase over time of IQ scores. If this represents a real increase in intelligence (as opposed to just measurement error) this means we would expect a modern clone of someone born in 1903 to be smarter than the original perhaps because a reduced pathogenic load is making nearly everyone more intelligent.
On the no side, the more exceptional someone is, the more regression to the mean we should expect from the clones. If your intelligence is some combination of genes and luck then the smartest person ever should have had an enormous amount of luck (say in terms of how random noise influenced brain development) as well as exceptional genes. The clones, on average, will have much less brain development luck than the original did.
Regression to the mean isn’t really an issue here. Regression is a constant in terms of heritability/SDs: the nonlinearity/cherrypicking is already baked in. If, say, adult IQ is 80% heritable, then it deflates towards the mean by 20% on average no matter where you are on the spectrum of low/above-average. (This might be different if it turns out to be driven by rare genes, which it wasn’t for IQ, but since we’re discussing clones that wouldn’t matter anyway.) So if von Neumann is at +5SD, then he is expected to regress back to 4.47SD, just like someone at 3SD regresses back to 2.6 and someone at 1SD to 0.89 and so on. It may be higher or lower, but him simply being extreme doesn’t matter AFAIK. (If you condition on more information like his family background, you could argue he’ll regress to a higher mean, so even less of a problem.)
What’s interesting here, and might be driving your intuition about clones being a disappointment, is that if you select high enough and the heritability is high enough, then even as you drive the average of the clones very high compared to the population, they may have an increasingly low probability of matching or exceeding the original. (In the extreme case of a genetically fixed trait or 100% heritability, the clone must be identical to the original and will always match and never exceed.) This is because that remaining 20% variability may be ‘tight’ around the mean, I think. I didn’t calculate this out in detail but I did notice it while thinking about dog cloning: https://www.gwern.net/Clone#liability-threshold-model Still, even somewhat short of von Neumann is still with few peers and would have massive changes. (To put this in perspective, and contra JBlack (who really ought to work more with order statistics & normal tails if he thinks as tiny an effect as 100x is an upper bound when we are dealing with extremes selected out of millions or billions of people), if Neumann clones regress back to, say, 4.47SD, then in a country of 320m like the USA, there are ~1,200 such individuals, and so any scenario involving more than 1.2k clones would mean instantly doubling the total population of such individuals. And then there are tens of thousands of adoptions, and egg/sperm donations, in the USA each year...)
Anyway, the big imponderable here is that we aren’t really concerned with IQ: IQ is the consolation prize, and the keys under the lamppost. We want eminence, achievement, genius. The heritability of that is a puzzle. If you look at families, genius seems to run in them but in a way that looks like it’d have to be pretty weak additively; that would seem to be bad for the prospects of cloning if the additive heritability of this overall ‘achievement’ trait was low, but on the other hand, there’s good arguments and examples to think that personality, the next most important factor, is highly heritable and just highly nonadditive, and that achievement relies on many factors simultaneously and is emergenic—in which case it flips back to potentially highly heritable in a way where cloning works really well (and where embryo selection/IES/editing would not, incidentally, at our present state of knowledge of miserably poor personality GWASes etc). It’s hard to investigate because identical twins are just not that common and wouldn’t show up in compiling lists of eminent figures to try to estimate concordance rates. Still, perhaps the consolation prize is enough?
What’s interesting here, and might be driving your intuition about clones being a disappointment, is that if you select high enough and the heritability is high enough, then even as you drive the average of the clones very high compared to the population, they may have an increasingly low probability of matching or exceeding the original.
So to work it out: what percentage of clones, because of regression to the mean, would be expected to surpass the original on some quantitative trait?
Using again von Neumann at an arbitrary +5SD (roughly 80 such individuals in the USA), then clones are expected to regress back to 4.47SD, because IQ 80% heritable, leaving 20% leftover (most of it non-sharedenvironment).
20% variance is another way of saying a SD of 0.44 around the new mean of +4.47SD. How much luck does one need for ±0.44 to reach up from 4.47 to 5?
(5 − 4.47) / 0.44 = +1.2SD
≤1.2SD is 88% of the population (pnorm(1.2))
So only 100% − 88% = ~12% of the clones would match the original (ie 1 in 10 vs a base-rate of 1 in >4 million, a multiplier of >400,000×, as opposed to a measly 100× or something—that’s tail effects for you, always larger than you think).
You could also run this with my dog cloning code. I considered a scenario where there’s two thresholds: one for picking the elite donor, and then a more ordinary pragmatic threshold. (In that case, ‘best military dog anywhere’ and ‘acceptable military dog after training’.) But you can simply set the two thresholds equal and now it calculates the probability of a clone passing the original selection threshold (ie matching or exceeding the original—at least as far as you can tell by comparing!):
Because of thin tails, it’s unsurprising that the more extreme you get, the lower the probability gets: it just gets wildly harder and harder the more SDs out you go. (Similar to bivariate double-maxima.) But the reduced variation + higher mean also benefits from the tail effect in that it gets ever more effective compared to the baseline of random screening/larger samples; the further out you go, the lower your probability may be, but the more effective it is relative to the alternatives which get worse faster. It’s worth noting that a probability like ‘0.05’ is astonishingly huge compared to the base rate (that “5% probability of matching the original” is for pnorm(-8), which has a base rate of 6.22096057e-16, ie. there is not a single person in the world 8SDs out—should you have such a person and you want another such outlier, better get busy with the cloning research, otherwise, you’ll be waiting a while):
Regarding cloning and regression to the mean: Have you written somewhere about the influence of the maternal environment on genetics? One could imagine that part of what made von Neumann great were not just his own genes, but also those of his mother who carried him to term, and a clone of him would not have her maternal environment.
I guess to disentangle the effects of genes and maternal environment, there might be studies of paternal half-siblings, or of couples who had children both naturally and via egg donation.
By maternal environment, do you mean just home/rearing environment attribute to the mother rather than father, or the womb environment/dam effects? The former does exist (you can do neat designs these days like looking at IGEs of just genes in the mother but not father) but influences stuff like EDU much more than IQ; a clone is already maxed out on EDU potential so we don’t care if the adoptive placement gives mothers less keen on education than von Neumann’s parents were. Womb environments have also been measured, I think through designs like you suggest (or was it children-of-twins designs? I forget) and found to be generally unimportant despite some hype. After all, whether you correlate against the mother or father, or second-degree relatives in any direction, the correlations are similar...
Thanks for the answer! By maternal environment I indeed meant the latter rather than the former, i.e. womb environment etc., i.e. the part one might not be able to duplicate when cloning. But if that hardly matters in the general population, I guess that’s not much of a worry.
This is because that remaining 20% variability may be ‘tight’ around the mean, I think.
This is in fact the fatal flaw of cloning (with respect to producing high achievement individuals): it’s much worse than sexual reproduction at doing so, because it’s lower variance, and variance is your friend if you want rare outcomes!
After all, if we’re considering 100 clones of a high-achievement individual being raised by surrogates, the natural comparison is 100 genetic children of two high-achievement individuals being raised by surrogates. (Note: I’m not offering an opinion on the ethics of either, just that this is the most apples-to-apples comparison.) The latter is FAR more likely to produce a super-high-achievement individual, because it starts from the same additive-genetic baseline, but has higher variance due to also including the genetic variance introduced by meiosis.
The only way this analysis could be false is if the advantage of preserving non-additive genetic effects overwhelms the disadvantage of lacking genetic variance, but I would be surprised if that were the case.
Therefore, cloning is just bad (for this goal). Really it seems to have no use whatsoever, and given that it’s illegal and low probability of successful birth, why even bother? On the other hand, if you found consenting participants, distributing embryos from two selected high-achievement individuals to surrogates would be legal and technologically feasible today.
This is in fact the fatal flaw of cloning (with respect to producing high achievement individuals): it’s much worse than sexual reproduction at doing so, because it’s lower variance, and variance is your friend if you want rare outcomes!
No. Selection lets you drastically increase the mean of clones in a way at least twice as difficult as for obtaining equally-elite pairs of parents. You can get the tail just as much from increasing the mean as from increasing the variance. Both are your friend. This is also relevant to embryo selection when we consider the values of increasing embryo count/PGS/selection: https://www.gwern.net/Embryo-selection#optimizing-selection-procedures (It also doesn’t follow that cloning-like approaches using a single parent are unable to exploit any variance-increasing methods, see the gamete-selection section.)
After all, if we’re considering 100 clones of a high-achievement individual being raised by surrogates, the natural comparison is 100 genetic children of two high-achievement individuals being raised by surrogates.
No, it’s not. Who’s the female von Neumann whose eggs you’re thinking of using...?
Selection lets you drastically increase the mean of clones in a way at least twice as difficult as for obtaining equally-elite pairs of parents.
I honestly don’t know what you’re talking about here. What’s “twice as difficult”? Do you mean because you need to find two donors instead of one? I think finding donors is the easiest part, so that doesn’t seem like a problem to me.
(It also doesn’t follow that cloning-like approaches using a single parent are unable to exploit any variance-increasing methods, see the gamete-selection section.)
I was under the impression that we were not considering future technology (such as gamete selection). Cloning primates is current-day technology (though still immature).
Who’s the female von Neumann whose eggs you’re thinking of using...?
The same way you’d find a male donor? Just ask some high achievement women until you find a willing donor (and maybe check for high-achievement relatives and run some polygenic scores, if you want additional confidence). I don’t see why this is a problem.
Note that von Neumann is not a possibility with present-day technology anyway, since he’s dead, and current technology requires a living donor.
Please see the emergenesis link.
Ah, sorry, I missed that when reading your post the first time. It’s true that sufficiently important non-additive effects would overwhelm the disadvantage of lower variance. This becomes a quantitative question: in principle the calculation could come out in favor of either cloning or sexual-reproduction, depending on assumptions.
I had the general impression though that non-additive effects were believed to be of relatively low importance compared to additive effects, but I admit that I don’t know precisely how much lower, and even a small effect could matter when considering extreme outliers.
What’s “twice as difficult”? Do you mean because you need to find two donors instead of one?
Yes, and it means you can’t get a gain by throwing out one donor. If you must include the lower-scoring runner-up of the opposite sex, that drags you further back to the mean. (Note that for all the talk of variability, von Neumann’s descendants aren’t that impressive, and this is true of most such.)
I was under the impression that we were not considering future technology (such as gamete selection).
I was under the impression we were, as no one has cloned a human at all and it is therefore future technology.
I don’t think gamete selection is all that hard or futuristic, either, merely uninvested in. There’s also chemical treatments to increase recombination rate (see the references), which is existing technology in plants/animals.
This becomes a quantitative question: in principle the calculation could come out in favor of either cloning or sexual-reproduction, depending on assumptions.
Indeed. Depending on where you think you can select to for donor cells, how heritable the trait of interest is, how many embryos you select from… Each of these has its own diminishing returns and costs and tradeoffs. Which is why I present many scenarios in my writeups. There is no substitute for working through the math—even simple toy models are indispensable, because intuition is weak here. Clones are really good in some scenarios; and really bad in others. It depends.
I had the general impression though that non-additive effects were believed to be of relatively low importance compared to additive effects, but I admit that I don’t know precisely how much lower, and even a small effect could matter when considering extreme outliers.
I would say that we are pretty sure that non-additive effects are unimportant for IQ. We are also reasonably sure that non-additives have been, overall, greatly overblown (I blame the medical Mendelians for this), at least for those human traits that are easy to measure: for example, Polderman et al 2015 finds no overall evidence for ADE instead of ACE in its twin mega-analysis, or Hivert et al 2020 scans 70 UKBB traits and finds 0% dominance and 6% epistasis. Not much there! We are also reasonably sure that for cases like that, the gap between the SNP additives (global mean ~20%?) & full heritability (~50%) is made up mostly of rare additive variants. Unfortunately, for personality, it happens to be a big exception: the SNP heritabilities can be as low as 0%, pointing to potentially huge roles for epistasis/dominance to explain the identical twin correlations (often >50%). And no one knows how ‘eminence’ works in part because it is intrinsically extremely debatable and hard to measure—but there is clearly a lot of variance unexplained by mere IQ, and other things are necessary, and what everyone tends to conclude (from Galton to Eysenck to Jensen to Simonton on) is that personality and personality-like traits such as motivation is a big part of the missing puzzle. So...
The emergenesis model is the best I’ve seen anyone propose which is consistent with the family-level observations, inadequacy of IQ to explain everything (and far grosser inadequacy of environmental causes like SES), and non-additivity of personality and similar traits. But it hasn’t yet (and may never be given the paucity of data) been pursued to the quantitative point where you could hope to really compare it, which is why I only give numbers for IQ above. That’s where the light from the lamppost is.
Thanks, this discussion has improved my understanding.
And no one knows how ‘eminence’ works in part because it is intrinsically extremely debatable and hard to measure—but there is clearly a lot of variance unexplained by mere IQ, and other things are necessary, and what everyone tends to conclude (from Galton to Eysenck to Simonton on) is that personality and personality-like traits such as motivation is a big part of the missing puzzle.
I’d be curious to know about the genetics of metrics like “number of patents authored”, where it’s measuring productive activity (instead of test performance and educational attainment).
Patents are zero-inflated: most people simply have zero lifetime patents. Not informative.
And when someone does have a patent, what does it mean? Patents are a pretty lousy measure: look at software patents. Sheer fishing expeditions and patent trolling (like Intellectual Ventures, which made patents by getting people around a table to shoot the wind and have a lawyer listen and write down patents for any random idea someone idly speculated about). When you think of eminent figures like Einstein or von Neumann, how many patents do you think they had? Einstein had over 50, but few have any relationship to what he’s famous for, and would he have that many if he hadn’t literally worked in a patent office? And there are loads of people with far more than 50. Von Neumann also had some patents, but again nothing remotely like his stature*. Arguably, after a certain point, having more patents means you are less eminent and you’re some sort of hired gun grinding out paperwork. (I think of this every time I hear about how IBM, or China, incentivizes patents with big bonuses and accordingly received a record number of patents that year. Hasn’t done them much good long-term that I can tell...) And there are many areas of achievement where patents are entirely irrelevant.
If you pulled together a population-sized genealogy or registry (Scandinavia would do the trick, or one of the American genealogies to cross-reference with the USPTO), I don’t know what the results would be in terms of an ACE model, but I don’t think it would change any minds either way about emergenesis.
* The patent von Neumann is best known for is the one he didn’t get but instead torpedoed by publishing about the design of a computer, thereby helping usher in the age of the digital computer immediately instead of it being controlled by a monopolist for decades.
I think of this every time I hear about how IBM, or China, incentivizes patents with big bonuses and accordingly received a record number of patents that year. Hasn’t done them much good long-term that I can tell...
Yeah, I personally have 2 patents to my name through this kind of Goodharting. (Higher management provided the incentives, lower management encouraged me to apply even knowing it probably wasn’t economically worthwhile.)
Not really, given the huge disparity in numbers - unless you have a magic way of feeding/housing/clothing/caring for children which costs far less than is currently possible? (And note that we know baby warehousing REALLY doesn’t work well.)
Would the clones be at least as smart as the original? On the yes side we have the Flynn Effect, which is the steady increase over time of IQ scores. If this represents a real increase in intelligence (as opposed to just measurement error) this means we would expect a modern clone of someone born in 1903 to be smarter than the original perhaps because a reduced pathogenic load is making nearly everyone more intelligent.
On the no side, the more exceptional someone is, the more regression to the mean we should expect from the clones. If your intelligence is some combination of genes and luck then the smartest person ever should have had an enormous amount of luck (say in terms of how random noise influenced brain development) as well as exceptional genes. The clones, on average, will have much less brain development luck than the original did.
Regression to the mean isn’t really an issue here. Regression is a constant in terms of heritability/SDs: the nonlinearity/cherrypicking is already baked in. If, say, adult IQ is 80% heritable, then it deflates towards the mean by 20% on average no matter where you are on the spectrum of low/above-average. (This might be different if it turns out to be driven by rare genes, which it wasn’t for IQ, but since we’re discussing clones that wouldn’t matter anyway.) So if von Neumann is at +5SD, then he is expected to regress back to 4.47SD, just like someone at 3SD regresses back to 2.6 and someone at 1SD to 0.89 and so on. It may be higher or lower, but him simply being extreme doesn’t matter AFAIK. (If you condition on more information like his family background, you could argue he’ll regress to a higher mean, so even less of a problem.)
What’s interesting here, and might be driving your intuition about clones being a disappointment, is that if you select high enough and the heritability is high enough, then even as you drive the average of the clones very high compared to the population, they may have an increasingly low probability of matching or exceeding the original. (In the extreme case of a genetically fixed trait or 100% heritability, the clone must be identical to the original and will always match and never exceed.) This is because that remaining 20% variability may be ‘tight’ around the mean, I think. I didn’t calculate this out in detail but I did notice it while thinking about dog cloning: https://www.gwern.net/Clone#liability-threshold-model Still, even somewhat short of von Neumann is still with few peers and would have massive changes. (To put this in perspective, and contra JBlack (who really ought to work more with order statistics & normal tails if he thinks as tiny an effect as 100x is an upper bound when we are dealing with extremes selected out of millions or billions of people), if Neumann clones regress back to, say, 4.47SD, then in a country of 320m like the USA, there are ~1,200 such individuals, and so any scenario involving more than 1.2k clones would mean instantly doubling the total population of such individuals. And then there are tens of thousands of adoptions, and egg/sperm donations, in the USA each year...)
Anyway, the big imponderable here is that we aren’t really concerned with IQ: IQ is the consolation prize, and the keys under the lamppost. We want eminence, achievement, genius. The heritability of that is a puzzle. If you look at families, genius seems to run in them but in a way that looks like it’d have to be pretty weak additively; that would seem to be bad for the prospects of cloning if the additive heritability of this overall ‘achievement’ trait was low, but on the other hand, there’s good arguments and examples to think that personality, the next most important factor, is highly heritable and just highly nonadditive, and that achievement relies on many factors simultaneously and is emergenic—in which case it flips back to potentially highly heritable in a way where cloning works really well (and where embryo selection/IES/editing would not, incidentally, at our present state of knowledge of miserably poor personality GWASes etc). It’s hard to investigate because identical twins are just not that common and wouldn’t show up in compiling lists of eminent figures to try to estimate concordance rates. Still, perhaps the consolation prize is enough?
So to work it out: what percentage of clones, because of regression to the mean, would be expected to surpass the original on some quantitative trait? Using again von Neumann at an arbitrary +5SD (roughly 80 such individuals in the USA), then clones are expected to regress back to 4.47SD, because IQ 80% heritable, leaving 20% leftover (most of it non-sharedenvironment).
20% variance is another way of saying a SD of 0.44 around the new mean of +4.47SD. How much luck does one need for ±0.44 to reach up from 4.47 to 5?
(5 − 4.47) / 0.44 = +1.2SD
≤1.2SD is 88% of the population (
pnorm(1.2))So only 100% − 88% = ~12% of the clones would match the original (ie 1 in 10 vs a base-rate of 1 in >4 million, a multiplier of >400,000×, as opposed to a measly 100× or something—that’s tail effects for you, always larger than you think).
You could also run this with my dog cloning code. I considered a scenario where there’s two thresholds: one for picking the elite donor, and then a more ordinary pragmatic threshold. (In that case, ‘best military dog anywhere’ and ‘acceptable military dog after training’.) But you can simply set the two thresholds equal and now it calculates the probability of a clone passing the original selection threshold (ie matching or exceeding the original—at least as far as you can tell by comparing!):
Because of thin tails, it’s unsurprising that the more extreme you get, the lower the probability gets: it just gets wildly harder and harder the more SDs out you go. (Similar to bivariate double-maxima.) But the reduced variation + higher mean also benefits from the tail effect in that it gets ever more effective compared to the baseline of random screening/larger samples; the further out you go, the lower your probability may be, but the more effective it is relative to the alternatives which get worse faster. It’s worth noting that a probability like ‘0.05’ is astonishingly huge compared to the base rate (that “5% probability of matching the original” is for
pnorm(-8), which has a base rate of 6.22096057e-16, ie. there is not a single person in the world 8SDs out—should you have such a person and you want another such outlier, better get busy with the cloning research, otherwise, you’ll be waiting a while):Regarding cloning and regression to the mean: Have you written somewhere about the influence of the maternal environment on genetics? One could imagine that part of what made von Neumann great were not just his own genes, but also those of his mother who carried him to term, and a clone of him would not have her maternal environment.
I guess to disentangle the effects of genes and maternal environment, there might be studies of paternal half-siblings, or of couples who had children both naturally and via egg donation.
By maternal environment, do you mean just home/rearing environment attribute to the mother rather than father, or the womb environment/dam effects? The former does exist (you can do neat designs these days like looking at IGEs of just genes in the mother but not father) but influences stuff like EDU much more than IQ; a clone is already maxed out on EDU potential so we don’t care if the adoptive placement gives mothers less keen on education than von Neumann’s parents were. Womb environments have also been measured, I think through designs like you suggest (or was it children-of-twins designs? I forget) and found to be generally unimportant despite some hype. After all, whether you correlate against the mother or father, or second-degree relatives in any direction, the correlations are similar...
Thanks for the answer! By maternal environment I indeed meant the latter rather than the former, i.e. womb environment etc., i.e. the part one might not be able to duplicate when cloning. But if that hardly matters in the general population, I guess that’s not much of a worry.
This is in fact the fatal flaw of cloning (with respect to producing high achievement individuals): it’s much worse than sexual reproduction at doing so, because it’s lower variance, and variance is your friend if you want rare outcomes!
After all, if we’re considering 100 clones of a high-achievement individual being raised by surrogates, the natural comparison is 100 genetic children of two high-achievement individuals being raised by surrogates. (Note: I’m not offering an opinion on the ethics of either, just that this is the most apples-to-apples comparison.) The latter is FAR more likely to produce a super-high-achievement individual, because it starts from the same additive-genetic baseline, but has higher variance due to also including the genetic variance introduced by meiosis.
The only way this analysis could be false is if the advantage of preserving non-additive genetic effects overwhelms the disadvantage of lacking genetic variance, but I would be surprised if that were the case.
Therefore, cloning is just bad (for this goal). Really it seems to have no use whatsoever, and given that it’s illegal and low probability of successful birth, why even bother? On the other hand, if you found consenting participants, distributing embryos from two selected high-achievement individuals to surrogates would be legal and technologically feasible today.
No. Selection lets you drastically increase the mean of clones in a way at least twice as difficult as for obtaining equally-elite pairs of parents. You can get the tail just as much from increasing the mean as from increasing the variance. Both are your friend. This is also relevant to embryo selection when we consider the values of increasing embryo count/PGS/selection: https://www.gwern.net/Embryo-selection#optimizing-selection-procedures (It also doesn’t follow that cloning-like approaches using a single parent are unable to exploit any variance-increasing methods, see the gamete-selection section.)
No, it’s not. Who’s the female von Neumann whose eggs you’re thinking of using...?
Please see the emergenesis link.
I honestly don’t know what you’re talking about here. What’s “twice as difficult”? Do you mean because you need to find two donors instead of one? I think finding donors is the easiest part, so that doesn’t seem like a problem to me.
I was under the impression that we were not considering future technology (such as gamete selection). Cloning primates is current-day technology (though still immature).
The same way you’d find a male donor? Just ask some high achievement women until you find a willing donor (and maybe check for high-achievement relatives and run some polygenic scores, if you want additional confidence). I don’t see why this is a problem.
Note that von Neumann is not a possibility with present-day technology anyway, since he’s dead, and current technology requires a living donor.
Ah, sorry, I missed that when reading your post the first time. It’s true that sufficiently important non-additive effects would overwhelm the disadvantage of lower variance. This becomes a quantitative question: in principle the calculation could come out in favor of either cloning or sexual-reproduction, depending on assumptions.
I had the general impression though that non-additive effects were believed to be of relatively low importance compared to additive effects, but I admit that I don’t know precisely how much lower, and even a small effect could matter when considering extreme outliers.
Yes, and it means you can’t get a gain by throwing out one donor. If you must include the lower-scoring runner-up of the opposite sex, that drags you further back to the mean. (Note that for all the talk of variability, von Neumann’s descendants aren’t that impressive, and this is true of most such.)
I was under the impression we were, as no one has cloned a human at all and it is therefore future technology.
I don’t think gamete selection is all that hard or futuristic, either, merely uninvested in. There’s also chemical treatments to increase recombination rate (see the references), which is existing technology in plants/animals.
Indeed. Depending on where you think you can select to for donor cells, how heritable the trait of interest is, how many embryos you select from… Each of these has its own diminishing returns and costs and tradeoffs. Which is why I present many scenarios in my writeups. There is no substitute for working through the math—even simple toy models are indispensable, because intuition is weak here. Clones are really good in some scenarios; and really bad in others. It depends.
I would say that we are pretty sure that non-additive effects are unimportant for IQ. We are also reasonably sure that non-additives have been, overall, greatly overblown (I blame the medical Mendelians for this), at least for those human traits that are easy to measure: for example, Polderman et al 2015 finds no overall evidence for ADE instead of ACE in its twin mega-analysis, or Hivert et al 2020 scans 70 UKBB traits and finds 0% dominance and 6% epistasis. Not much there! We are also reasonably sure that for cases like that, the gap between the SNP additives (global mean ~20%?) & full heritability (~50%) is made up mostly of rare additive variants. Unfortunately, for personality, it happens to be a big exception: the SNP heritabilities can be as low as 0%, pointing to potentially huge roles for epistasis/dominance to explain the identical twin correlations (often >50%). And no one knows how ‘eminence’ works in part because it is intrinsically extremely debatable and hard to measure—but there is clearly a lot of variance unexplained by mere IQ, and other things are necessary, and what everyone tends to conclude (from Galton to Eysenck to Jensen to Simonton on) is that personality and personality-like traits such as motivation is a big part of the missing puzzle. So...
The emergenesis model is the best I’ve seen anyone propose which is consistent with the family-level observations, inadequacy of IQ to explain everything (and far grosser inadequacy of environmental causes like SES), and non-additivity of personality and similar traits. But it hasn’t yet (and may never be given the paucity of data) been pursued to the quantitative point where you could hope to really compare it, which is why I only give numbers for IQ above. That’s where the light from the lamppost is.
Thanks, this discussion has improved my understanding.
I’d be curious to know about the genetics of metrics like “number of patents authored”, where it’s measuring productive activity (instead of test performance and educational attainment).
That’s an example of what I mean by debatable.
Patents are zero-inflated: most people simply have zero lifetime patents. Not informative.
And when someone does have a patent, what does it mean? Patents are a pretty lousy measure: look at software patents. Sheer fishing expeditions and patent trolling (like Intellectual Ventures, which made patents by getting people around a table to shoot the wind and have a lawyer listen and write down patents for any random idea someone idly speculated about). When you think of eminent figures like Einstein or von Neumann, how many patents do you think they had? Einstein had over 50, but few have any relationship to what he’s famous for, and would he have that many if he hadn’t literally worked in a patent office? And there are loads of people with far more than 50. Von Neumann also had some patents, but again nothing remotely like his stature*. Arguably, after a certain point, having more patents means you are less eminent and you’re some sort of hired gun grinding out paperwork. (I think of this every time I hear about how IBM, or China, incentivizes patents with big bonuses and accordingly received a record number of patents that year. Hasn’t done them much good long-term that I can tell...) And there are many areas of achievement where patents are entirely irrelevant.
If you pulled together a population-sized genealogy or registry (Scandinavia would do the trick, or one of the American genealogies to cross-reference with the USPTO), I don’t know what the results would be in terms of an ACE model, but I don’t think it would change any minds either way about emergenesis.
* The patent von Neumann is best known for is the one he didn’t get but instead torpedoed by publishing about the design of a computer, thereby helping usher in the age of the digital computer immediately instead of it being controlled by a monopolist for decades.
Yeah, I personally have 2 patents to my name through this kind of Goodharting. (Higher management provided the incentives, lower management encouraged me to apply even knowing it probably wasn’t economically worthwhile.)
This is very true, and a good reason to clone millions of von Neumanns, rather than just a handful.
Expected value compared to hiring the top 100 people in the international math Olympiad each of the next 20 years?
Depends on the price of creating and raising clones.
Not really, given the huge disparity in numbers - unless you have a magic way of feeding/housing/clothing/caring for children which costs far less than is currently possible? (And note that we know baby warehousing REALLY doesn’t work well.)