What kind of traits can narrow sense heritability particularly apply to?

Narrow sense heritability is a concept used in quantitative genetics to determine the proportion of phenotypic variance in a trait that can be attributed to additive genetic variance. This type of heritability is most applicable to continuous traits, such as height or weight, since these traits are influenced by multiple genes and environmental factors.

Continuous traits exhibit a range of phenotypes and can show a normal distribution in a population. This characteristic allows researchers to measure subtle variations and assess how changes in genotype can influence the phenotypic expression of the trait. The higher the narrow sense heritability, the more likely that offspring will resemble their parents in terms of that continuous trait due to the additive effects of alleles.

In contrast, simple Mendelian traits, which are typically governed by one or two genes and exhibit discrete categories, do not effectively illustrate narrow sense heritability because their inheritance patterns do not typically involve additive genetic variance. Highly complex traits influenced by many factors or qualitative traits that are easily observable also do not align with the definition and application of narrow sense heritability in the same way that continuous traits do. This makes continuous traits like height or weight the most relevant for this particular concept.