IQ is highly heritable. If I understand this presentation by Steven Hsu correctly [https://www.cog-genomics.org/static/pdf/ggoogle.pdf slide 20] he suggests that mean child IQ relative to population mean is approximately 60% of distance from population mean to parental average IQ. Eg Dad at +1 S.D. Mom at +3 S.D gives children averaging about 0.6*(1+3)/2 = +1.2 S.D. This basic eugenics give a very easy/cheap route to lifting average IQ of children born by about 1 S.D by using +4 S.D sperm donors. There is no other tech (yet) that can produce such gains as old fashioned selective breeding.
It also explains why rich dynasties can maintain average IQ about +1SD above population in their children—by always being able to marry highly intelligent mates (attracted to the money/power/prestige)
Heritability is measured in a way that rules that out. See e.g. Judith Harris or Bryan Caplan for popular expositions about the relevant methodologies & fine print.
IQ is highly heritable. If I understand this presentation by Steven Hsu correctly [https://www.cog-genomics.org/static/pdf/ggoogle.pdf slide 20] he suggests that mean child IQ relative to population mean is approximately 60% of distance from population mean to parental average IQ. Eg Dad at +1 S.D. Mom at +3 S.D gives children averaging about 0.6*(1+3)/2 = +1.2 S.D. This basic eugenics give a very easy/cheap route to lifting average IQ of children born by about 1 S.D by using +4 S.D sperm donors. There is no other tech (yet) that can produce such gains as old fashioned selective breeding.
It also explains why rich dynasties can maintain average IQ about +1SD above population in their children—by always being able to marry highly intelligent mates (attracted to the money/power/prestige)
Or, it might be that high IQ parents raise their children in a way that’s different from low IQ and it has nothing to do with genetics at all?
Heritability is measured in a way that rules that out. See e.g. Judith Harris or Bryan Caplan for popular expositions about the relevant methodologies & fine print.