Re:Most Reported Genetic Associations with Intelligence are ...
by samatman on Tuesday October 08, 2013 @01:40PM
(#6516488)
Heritability is related to the degree to which a trait is genetically determined. The relationship is far from trivial.
Skin color makes this much easier to understand. Imagine a couple, where the man and the woman each have one Scandinavian parent and one Bantu parent. Their children could have almost any skin shade.
If they have identical twins, those twins will have the same shade of skin. Skin color is genetically determined but the heritability varies.
Imagine two people who have the same skin color as our first two, but they come from an island population founded by Norwegians and Nigerians exclusively. They are 20th generation, or 50th. Now, it is likely the skin color of their children will be the same as their own.
Intelligence inherits upon many factors. Even identifying those factors proves to be elusive and hard. The good evidence that intelligence is genetic is twin studies: the good evidence that it is variable in heritability is every family you've ever known.
Skin color makes this much easier to understand. Imagine a couple, where the man and the woman each have one Scandinavian parent and one Bantu parent. Their children could have almost any skin shade.
If they have identical twins, those twins will have the same shade of skin. Skin color is genetically determined but the heritability varies.
Imagine two people who have the same skin color as our first two, but they come from an island population founded by Norwegians and Nigerians exclusively. They are 20th generation, or 50th. Now, it is likely the skin color of their children will be the same as their own.
Intelligence inherits upon many factors. Even identifying those factors proves to be elusive and hard. The good evidence that intelligence is genetic is twin studies: the good evidence that it is variable in heritability is every family you've ever known.