Why Within-Group Heritability Cannot Explain a Between-Group Difference
The deepest and most misused heritability point, and the one the fence most depends on. A heritability estimated inside one population is silent about why two populations' means differ, because the causes of variation within a group and the causes of a gap between groups are separate questions answered by separate designs. Built directly on the variance split and on the population-referent node, so it lands as arithmetic rather than as an assertion.
Questions this Concept answers
- Why is a heritability of \( h^{2} = 0.17 \) for voice pitch silent about why two populations differ in average pitch?
Heritability of IQ
Heritability estimates the share of variation within one population that tracks genetic differences among its members — it is a statement about differences inside a group, not about what causes any i…