Identical twins reared together: .85 correlation in IQ
Fraternal twins reared together: .55 correlation in IQ
Identical twins reared apart: .75 correlation in IQ
And the genetic correlation grows as children age.
No, genetic studies did not "demolish" heritability estimates, they set a floor on them. Genetic studies do not and cannot (currently) predict all phenotypic outcomes, they set the floor on how much variation can be caused by genetic differences.
The genetic predictions don't even directly contradict, never mind demolish, the twin study findings.
The "missing heritability problem" is only a problem if one believes our genetic analysis techniques are comprehensive, but we already know they're not. For example, current methods are extremely limited in detecting gene-gene interactions, which we have good reason to suspect are widespread (otherwise making new genetic drugs would be trivial).
Fraternal twins reared together: .55 correlation in IQ
Identical twins reared apart: .75 correlation in IQ
And the genetic correlation grows as children age.
No, genetic studies did not "demolish" heritability estimates, they set a floor on them. Genetic studies do not and cannot (currently) predict all phenotypic outcomes, they set the floor on how much variation can be caused by genetic differences.
The genetic predictions don't even directly contradict, never mind demolish, the twin study findings.
The "missing heritability problem" is only a problem if one believes our genetic analysis techniques are comprehensive, but we already know they're not. For example, current methods are extremely limited in detecting gene-gene interactions, which we have good reason to suspect are widespread (otherwise making new genetic drugs would be trivial).