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hyperion2010

The burakumin are the best argument against genetic causes of heritable lower intelligence (often invoked when talking about African American populations). In Japan many burakumin show significantly lower scores on standardized intelligence tests, however when they migrate out of Japan their scores recover to normal levels. Social caste is heritable. This was a favorite zinger that my evolutionary biology teacher liked to spring on unsuspecting students that tried to argue that they could demonstrate that low iq among AAs was due to genetic differences.

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They really are not a good argument against genetic causes of heritability of lower IQ scores in other groups. Their example (if true) only serves to proof that in their cases low IQ was cause by environment, which as partial cause for low IQ is not debated by anyone credible. It says nothing about genetic causes in other groups at all.

Fair enough. But I think it is a good reminder that the gut reaction to invoke genetics when confronted with a heritable phenotype should be met with suspicion, especially given the tendency to treat 'intrinsic' traits as excuses for continued poor treatment/disregard.

I think better yet would be to condemn discrimination (i.e. favor social fairness) even if a certain genetic group is found to be causally associated with lower IQ. I think assuming we're all equal is as crippling to science/society as genetic supremacism. Understanding nuances of ethnic and cultural groups is something we should strive for. Diversity of traits, cultures is great.

Inasmuch as it makes sense to claim one's gut has any notion of genetics, I'd say the gut reaction of the vast majority of people is to reject any suggestion that there are intelligence differences between groups caused by genetics.

My gut supports group differences in intelligence. As Heinlein once wrote, if intelligence weren't heritable, you could teach calculus to a horse. It takes the entire intellectual edifice of modern radical egalitarianism to rob people of their common sense.

>It takes the entire intellectual edifice of modern radical egalitarianism to rob people of their common sense

It's not just 'radical egalitarianism'. The seemingly obvious explanation that such and such group are poor because they are genetically low IQ does not stand up to scientific investigation on the whole.

I'm not sure if the vast majority of people actually believe in that. Most educated Americans probably do. But I think there are a lot of people out there who still hold the older outdated incorrect view.

I hope you're right. My experience growing up makes me believe the opposite, but I know that my adolescence is only anecdotal in the scheme of things. I think the best we can do is silently acknowledge that black people are likely to have had a different set of opportunities than white people and apply that knowledge judiciously as necessary.

That isn't a good argument considering immigration policies in countries select for successful outliers.

If you don't think intelligence is heritable, you're delusional. Its quite easy to see in the field -- I bet the smartest kids in your class, I'm talking about the naturally quick learners not the hardest working, also have naturally bright parents.

Intelligence and social class are both heritable traits:

http://www.economist.com/news/books-and-arts/21595396-new-st...

>> the best argument against genetic causes of heritable lower intelligence

> If you don't think intelligence is heritable, you're delusional

GP was saying intelligence is heritable, but not necessarily via genetics. Bright parents are likely to be fairly successful and better able to provide a stimulating environment & nutrition that's needed for a kid to be smart (i.e. provide a nurturing environment)

This is not what the data suggest.

From the wiki article: adoption studies show that by adulthood adoptive siblings aren't more similar in IQ than strangers (Bouchard 1998), while adult full siblings show an IQ correlation of 0.6.

An interesting survey summary of the studies by Kaufman 2009 of IQ correlation between groups:

* Same person (tested twice) .95

* Identical twins—Reared together .86

* Identical twins—Reared apart .76

* Fraternal twins—Reared together .55

* Fraternal twins—Reared apart .35

* Biological siblings—Reared together .47

* Biological siblings—Reared apart .24

* Unrelated children—Reared together—Children .28

* Unrelated children—Reared together—Adults .04

* Cousins .15

* Parent-child—Living together .42

* Parent-child—Living apart .22

* Adoptive parent–child—Living together .19

This also seems to support genetic heritability being large and environmental heritability being small (and almost insignificant by adulthood).

Sounds like a 'just so story' any research? The opposing view sounds more legit (There is no actual study) -

https://unsafeharbour.wordpress.com/2012/01/13/burakumin-and...

> This was a favorite zinger that my evolutionary biology teach liked to spring on unsuspecting students that tried to argue that they could demonstrate that low iq among AAs was due to genetic differences.

And what happens when AAs migrate out of America, or when Africans migrate into America, hmm? The debate is not that simplistic and easily resolved, and your professor did you a disservice by pretending that it is and not discussing why his anecdote is not airtight (for example, immigrant samples are almost always contaminated by serious selection effects which are hard to measure and vary by group). By the way, how sure are you that your professor was even right in the first place (https://unsafeharbour.wordpress.com/2012/01/13/burakumin-and...)?

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