Which statement is false about heritability and repeatability?

Which statement is false about heritability and repeatability?

• A. They are population parameters
• B. Heritability indicates genetic contribution
• C. Repeatability measures cross-cycle consistency
• D. They are identical in interpretation

Answer: (D)

Heritability and repeatability are both population-level measures of variation, but they describe different sources and aspects of that variation. Heritability is the proportion of phenotypic variance among individuals in a population that is due to genetic differences (typically additive genetics in practical breeding). It tells you how much of the observed differences you might expect to pass on to offspring and how responsive selection could be in that population. Repeatability, on the other hand, deals with how consistent an individual’s measurements are across repeated evaluations or cycles. It combines genetic effects with permanent environmental effects (and measurement error), so it reflects the correlation between repeated records for the same animal rather than the pure genetic contribution to variation among individuals. Because these quantify different things, they are not identical in interpretation. The other statements correctly describe their nature as population parameters, that heritability reflects genetic contribution, and that repeatability measures consistency across repeated records.

Heritability and repeatability are both population-level measures of variation, but they describe different sources and aspects of that variation. Heritability is the proportion of phenotypic variance among individuals in a population that is due to genetic differences (typically additive genetics in practical breeding). It tells you how much of the observed differences you might expect to pass on to offspring and how responsive selection could be in that population.

Repeatability, on the other hand, deals with how consistent an individual’s measurements are across repeated evaluations or cycles. It combines genetic effects with permanent environmental effects (and measurement error), so it reflects the correlation between repeated records for the same animal rather than the pure genetic contribution to variation among individuals.

Because these quantify different things, they are not identical in interpretation. The other statements correctly describe their nature as population parameters, that heritability reflects genetic contribution, and that repeatability measures consistency across repeated records.