Comment by bell-cot
6 days ago
In my mind, the bigger issue with twin studies trying to show that (say) IQ is highly genetic is that humans do not reproduce by cloning. And regression toward the mean is very much a thing for heritable traits.
In other words - Junior should not be presumed to be smarter, fitter, more deserving, or destined for success, just because his parents did well. No matter how attractive that conclusion might sound, to people who consider themselves to be the "better" sort.
That doesn't sound like a problem with twin studies exploring the degree to which IQ is genetic, that sounds like a problem with people treating aggregate tendencies and associations as a basis for individual discrimination.
Yes-ish. Hence my use of "issue".
The problem is most people's zealous desire to read socially self-serving conclusions into any data they can find on such subjects. And when they really like the Q.E.D. punchline, humans have very low standards for the "logic" used to reach it.
"most people's zealous desire to read socially self-serving conclusions into any data they can find"
what planet are you living on?
also your comment was completely incorrect and missing the entire point of twin studies.
iq is "polygenetic" with the consensus estimates at 50-80% based on genes
success has components of luck as in "right place, right time" for someone with the right qualities and connections, and many of the very successful are quick to admit this
I am a 3rd generation machinist along the paternal line, and although the machines I operate are in expensive labs, those my father and grandfather operated were probably just as challenging. Engineering also seems to often run in the family. How much is nature and nuture? "It varies" is a safe response
Whoah, no, there is definitely not a consensus for 50-80%, and most of what's being published now refutes the 80% end of that range --- the 80% estimates come from underpowered studies like MISTRA that improperly assumed independent environments for twins reared apart.
okay, I saw the paper saying 500 genes are involved. So does a single number for iq mean anything? Does the number depend upon what is tested?
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