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"A great deal of time has been wasted in the effort of measuring the heritability of traits in the false expectation that somehow the genetic nature of psycholo

"A great deal of time has been wasted in the effort of measuring the heritability of traits in the false expectation that somehow the genetic nature of psychological phenomena would be revealed." There is a strong cultural bias among much of the research community to go out of their way to deny any genetic factors in intelligence. Perhaps this is well intentioned, but it is absurd. I have come across very few squirrels that have mastered fire, or could be taught calculus, or even addition. I doubt that this is cultural or due to the squirrels upbringing, diet, social status, or how many books the squirrel has available to it, or the quality of it's teachers, or pathogens. Clearly then, it is possible for genetics to completely dominate other factors in determining intelligence. In the animal kingdom at large heredity/genetics account for basically all of the variation in intelligence. The unanswered question is whether there is enough genetic diversity across the human species to cause intelligence to be significantly hereditable. The fear among scientists that try to keep the lid on this question is that the answer might be yes, and worse that such variations will correlate with geographic or national groupings. This would put a very nasty perceived scientific stamp of approval on racism (even though this would be unjustified), and could over time lead to discrimination and 'scientific racism'. Anyway, in the end science will uncover the truth here, and in the meantime it is probably very prudent to not make any potentially inflammatory statements and to be very cautious about any studies that could fuel hate. I just find it absurd that whenever this kind of question comes up people start denying that there is any hereditary component of intelligence, and that IQ is completely meaningless, etc.

ralfn 14y ago
I love your example! Way out of my depth here, but i do have a question: The squirrel obviously has a genetic trait that causes it to have a small brain. We can tell its iq just by looking at it, without considering its DNA. Would the same logic apply, when there is no visual/physical trait present? Can one brain cell be dumber than another? Could they be wired in a less optimal way? Genetics likely explain the difference between a retard and a functioning human, but csn they also explain the difference between an iq of 100 and an iq of 105? When people have this debate about intelligence, the inevitable political argument is that maybe, we as a society could invest more in ourselves, our children and our neighbours children. The relevant question, perhaps, should be: how much impact could "nurture" have? Is somebody with an iq of 120 physically limited to become smarter? Or is that person already in the range, where the genes were all good? I dont think anybody doubts that a retarded person has a genetic disadvantage. But does the same apply to an average human being? And if that limit exist, is it a personal limit, or one you share with most other humans on this planet?
hazov 14y ago
I just curious how you can support your point about squirrels, besides you falling prey of the bias of trying to advance an argument with a sole point. For example, can these squirrels ancestors had better nutrition than the average squirrel, can we know about that just after seeing they mastering fire or wondering if they could learn calculus? I believe this type of question, the relation between nutrition and intelligence, can be answered much easily than searching for genes and looking for some desirable psychological trait in there, this can be easily tested in animals as well in a large couple of generations. Either way I am not a biologist or even an psychologist so this is my take as a mathematician/statician. Also I'm not so confident science will ever come as close to explaining this completely.
- justin_vanw 14y ago
  My point is that humans are much more intelligent than squirrels. Is this because of environment? Not at all, it is because we have the genetic programming to develop huge brains. The difference in intelligence between humans and squirrels is determined almost entirely by heredity. The reason I point this out is that it is very common to see comments about heredity not being a factor in human intelligence. It may well be that heredity does not explain differences in intelligence between two humans, or it may be that heredity almost completely explains any differences in intelligence among humans. Science will eventually figure out the truth of the matter. However, heredity plays a very dominant role in determining intelligence, the only question is whether humans are all so genetically similar with regards to intelligence that environmental factors dominate genetic factors. EDIT: The way I phrased the first paragraph sets up a false choice. Intelligence differences among humans could be hereditary, environmental, or most likely a complex combination of the two.
  - hazov 14y ago
    In the comments of this post however I saw exactly the same point you're saying in your first paragraph, maybe in other discussion forums people denying this is more common.
astrodust 14y ago
The performance of laboratory mice in mazes varies considerably among tested populations, with some mice clearly being "smarter" than others. It's possible to train a mouse to be smarter, to learn, but the effect is only a few standard deviations from the norm at best, not orders of magnitude smarter. Remember that genetics is, at best, all about probabilities. Just because your parents are athletic is no guarantee that you're an athlete. There's always a one in four chance that you get the worst possible pairing of genes, after all. Intelligence is a complicated thing. A child who can remember things easily will be considered very "smart" even if they can't do much with that information, whereas one who's very clever at figuring things out will be considered "stupid" if they aren't able to memorize as well. IQ is such an arbitrary metric that it hardly deserves scientific consideration. It completely glosses over any unusual talents someone might have.
uncomfytruths 14y ago
You're not alone. I've always wondered, how come different dog breeds have different behavior and intelligence levels. Yet certain breeds are much smarter than others and capable of greater learning capacity. Any kind of comparison, even scientific, between human races would be seen as racist and thrown out immediately. It conjures up all sorts of negative emotions. Hitler, Nazis, Eugenics, Master Races, Holocausts. I think deep down inside we are slaves to our genetics and many people know so and have significant evidence for it but are keeping quiet. And I don't blame them. The repercussions of telling the human race "Your success, happiness, intelligence, health, and entire life is limited by your genetics." would be horrific. Half the world would be on anti-depression medications if you told them that and proved it. No one wants to be told who they are before they're given a chance to discover themselves on their own. Also, genetics are not the end all of success. Just because someone doesn't have the genes that make them more likely to be successful doesn't mean they'll never be successful. There are other ways around. Aggression, luck, money, hard work, etc.... For instance, Ashkenazi Jews have the highest intelligence and very poor Spatial intelligence according to research. After them come north east Asians. Jews are disproportionately successful in numerous fields. 25% of Nobel prize winners are jewish and this is increasing. All of the major Hollywood studios were started by jews and are currently dominated by jews. The NYT's Joel Stein could only find 5 non-jewish executives in all of Hollywood. Most of the top writers are also jewish. Banking and finance is dominated by them as well. So is the fashion industry: Marc Jacobs, Ralph Lauren, Marc Echo, Calvin Klein, Estée Lauder, Kenneth Cole, and others are jewish. Levi's jeans as well. 2 of the internet's biggest companies, Google and Facebook were started by jews Larry Page, Sergey Brin, Mark Zuckerberg. People's refusal to acknowledge that genetics has anything to do with intelligence is exactly what has sprouted numerous conspiracy theories to try to explain why jews are so well achieved. Also, look at men vs women. How many wars have women started compared to men? Nearly every war, genocide, and conflict has been caused entirely by men. Why is it that we never see the female versions of Hitler, Gangis Kahn, Napoleon, Stalin, etc... Because evolution has created extremely violent men (not all of us of course). Evolution wise, we're disposable. Women are not. The human race can easily be replenished with 99 women and 1 man. But not with 99 men and 1 women. And so women live much more "slow but steady" lifestyles while men are more likely to live "risky" lifestyles. Rewards are proportionate to risk. So men reap the rewards when it comes to inventions, companies, religions, nation building, etc...
DividesByZero 14y ago
The squirrel example is absolutely absurd - there are clear physiological, morphological differences between human beings and squirrels that influence whether or not squirrels even have the capacity to master fire, or whatever other silly comparison you choose. Furthermore, I think you will find that environmental factors plainly influence the behavior of animal populations (squirrels, chimpanzees, birds - any kingdom, genus or species you choose) far more than any particular genetic variation among them - animals of the same species without abundant resources behave quite differently from animals of the same species in an environment of abundance (one need only look at any pest species - animal or plant - to see that this is true). There does not exist much variation across 'societies' of animals within the same species - one tribe of baboons is much like another tribe - but there exist vast gaps between societies of human beings, so far as these gaps influence the environment of individuals among populations, and entire populations as a whole. There is no physiological model for human intelligence, and since only physiological traits are inheritable (though psychological traits may be derived from morphological differences) there is no model for genetic influence on intelligence. Since there is no model, you can only blindly test a black-box hypothesis - and the results from those tests appear to support the conclusion that there does not exist any inheritable, physiological difference that would influence intelligence, controlling for societal factors.
- DividesByZero 14y ago
  I would also add, that the political agenda is not from those advancing the idea that environment influences human development, but from those that contend it is genetics. Consider the sorts of policies someone who wanted to maximise productivity in society would develop if it was found that genetics was a greater influencing factor - why would you support development for poor populations of people if it was found that they simply don't have the same development potential? You would simply screen for the 'genius' gene and push the rest of society toward a supporting role. In the case of the environmental view, you must now implement policies that raise the living conditions for the majority of people in society - better and more schools, better and more social programs, better opportunity - that's expensive, and there's not much money to be made.
  - 14y ago

ralfn 14y ago

I love your example! Way out of my depth here, but i do have a question: The squirrel obviously has a genetic trait that causes it to have a small brain. We can tell its iq just by looking at it, without considering its DNA. Would the same logic apply, when there is no visual/physical trait present? Can one brain cell be dumber than another? Could they be wired in a less optimal way? Genetics likely explain the difference between a retard and a functioning human, but csn they also explain the difference between an iq of 100 and an iq of 105? When people have this debate about intelligence, the inevitable political argument is that maybe, we as a society could invest more in ourselves, our children and our neighbours children. The relevant question, perhaps, should be: how much impact could "nurture" have? Is somebody with an iq of 120 physically limited to become smarter? Or is that person already in the range, where the genes were all good? I dont think anybody doubts that a retarded person has a genetic disadvantage. But does the same apply to an average human being? And if that limit exist, is it a personal limit, or one you share with most other humans on this planet?

hazov 14y ago

I just curious how you can support your point about squirrels, besides you falling prey of the bias of trying to advance an argument with a sole point. For example, can these squirrels ancestors had better nutrition than the average squirrel, can we know about that just after seeing they mastering fire or wondering if they could learn calculus? I believe this type of question, the relation between nutrition and intelligence, can be answered much easily than searching for genes and looking for some desirable psychological trait in there, this can be easily tested in animals as well in a large couple of generations. Either way I am not a biologist or even an psychologist so this is my take as a mathematician/statician. Also I'm not so confident science will ever come as close to explaining this completely.

justin_vanw 14y ago
My point is that humans are much more intelligent than squirrels. Is this because of environment? Not at all, it is because we have the genetic programming to develop huge brains. The difference in intelligence between humans and squirrels is determined almost entirely by heredity. The reason I point this out is that it is very common to see comments about heredity not being a factor in human intelligence. It may well be that heredity does not explain differences in intelligence between two humans, or it may be that heredity almost completely explains any differences in intelligence among humans. Science will eventually figure out the truth of the matter. However, heredity plays a very dominant role in determining intelligence, the only question is whether humans are all so genetically similar with regards to intelligence that environmental factors dominate genetic factors. EDIT: The way I phrased the first paragraph sets up a false choice. Intelligence differences among humans could be hereditary, environmental, or most likely a complex combination of the two.
- hazov 14y ago
  In the comments of this post however I saw exactly the same point you're saying in your first paragraph, maybe in other discussion forums people denying this is more common.

astrodust 14y ago

The performance of laboratory mice in mazes varies considerably among tested populations, with some mice clearly being "smarter" than others. It's possible to train a mouse to be smarter, to learn, but the effect is only a few standard deviations from the norm at best, not orders of magnitude smarter. Remember that genetics is, at best, all about probabilities. Just because your parents are athletic is no guarantee that you're an athlete. There's always a one in four chance that you get the worst possible pairing of genes, after all. Intelligence is a complicated thing. A child who can remember things easily will be considered very "smart" even if they can't do much with that information, whereas one who's very clever at figuring things out will be considered "stupid" if they aren't able to memorize as well. IQ is such an arbitrary metric that it hardly deserves scientific consideration. It completely glosses over any unusual talents someone might have.

uncomfytruths 14y ago

You're not alone. I've always wondered, how come different dog breeds have different behavior and intelligence levels. Yet certain breeds are much smarter than others and capable of greater learning capacity. Any kind of comparison, even scientific, between human races would be seen as racist and thrown out immediately. It conjures up all sorts of negative emotions. Hitler, Nazis, Eugenics, Master Races, Holocausts. I think deep down inside we are slaves to our genetics and many people know so and have significant evidence for it but are keeping quiet. And I don't blame them. The repercussions of telling the human race "Your success, happiness, intelligence, health, and entire life is limited by your genetics." would be horrific. Half the world would be on anti-depression medications if you told them that and proved it. No one wants to be told who they are before they're given a chance to discover themselves on their own. Also, genetics are not the end all of success. Just because someone doesn't have the genes that make them more likely to be successful doesn't mean they'll never be successful. There are other ways around. Aggression, luck, money, hard work, etc.... For instance, Ashkenazi Jews have the highest intelligence and very poor Spatial intelligence according to research. After them come north east Asians. Jews are disproportionately successful in numerous fields. 25% of Nobel prize winners are jewish and this is increasing. All of the major Hollywood studios were started by jews and are currently dominated by jews. The NYT's Joel Stein could only find 5 non-jewish executives in all of Hollywood. Most of the top writers are also jewish. Banking and finance is dominated by them as well. So is the fashion industry: Marc Jacobs, Ralph Lauren, Marc Echo, Calvin Klein, Estée Lauder, Kenneth Cole, and others are jewish. Levi's jeans as well. 2 of the internet's biggest companies, Google and Facebook were started by jews Larry Page, Sergey Brin, Mark Zuckerberg. People's refusal to acknowledge that genetics has anything to do with intelligence is exactly what has sprouted numerous conspiracy theories to try to explain why jews are so well achieved. Also, look at men vs women. How many wars have women started compared to men? Nearly every war, genocide, and conflict has been caused entirely by men. Why is it that we never see the female versions of Hitler, Gangis Kahn, Napoleon, Stalin, etc... Because evolution has created extremely violent men (not all of us of course). Evolution wise, we're disposable. Women are not. The human race can easily be replenished with 99 women and 1 man. But not with 99 men and 1 women. And so women live much more "slow but steady" lifestyles while men are more likely to live "risky" lifestyles. Rewards are proportionate to risk. So men reap the rewards when it comes to inventions, companies, religions, nation building, etc...

DividesByZero 14y ago

The squirrel example is absolutely absurd - there are clear physiological, morphological differences between human beings and squirrels that influence whether or not squirrels even have the capacity to master fire, or whatever other silly comparison you choose. Furthermore, I think you will find that environmental factors plainly influence the behavior of animal populations (squirrels, chimpanzees, birds - any kingdom, genus or species you choose) far more than any particular genetic variation among them - animals of the same species without abundant resources behave quite differently from animals of the same species in an environment of abundance (one need only look at any pest species - animal or plant - to see that this is true). There does not exist much variation across 'societies' of animals within the same species - one tribe of baboons is much like another tribe - but there exist vast gaps between societies of human beings, so far as these gaps influence the environment of individuals among populations, and entire populations as a whole. There is no physiological model for human intelligence, and since only physiological traits are inheritable (though psychological traits may be derived from morphological differences) there is no model for genetic influence on intelligence. Since there is no model, you can only blindly test a black-box hypothesis - and the results from those tests appear to support the conclusion that there does not exist any inheritable, physiological difference that would influence intelligence, controlling for societal factors.

DividesByZero 14y ago
I would also add, that the political agenda is not from those advancing the idea that environment influences human development, but from those that contend it is genetics. Consider the sorts of policies someone who wanted to maximise productivity in society would develop if it was found that genetics was a greater influencing factor - why would you support development for poor populations of people if it was found that they simply don't have the same development potential? You would simply screen for the 'genius' gene and push the rest of society toward a supporting role. In the case of the environmental view, you must now implement policies that raise the living conditions for the majority of people in society - better and more schools, better and more social programs, better opportunity - that's expensive, and there's not much money to be made.
- 14y ago