Threshold traits appear as discrete or categorical phenotypes but are influenced by an underlying continuous liability. Learn how genetic and environmental factors, thresholds, heritability, polygenic inheritance, and quantitative genetics shape these traits.
Common environmental effects are environmental influences shared by multiple individuals that contribute to phenotypic similarity. Learn how they affect family resemblance, heritability, genetic variance, breeding value, and quantitative genetic analysis.
Permanent environmental effects are lasting non-genetic influences that contribute to persistent differences among individuals. Learn how they affect repeatability, heritability, genetic variance, breeding value, selection accuracy, and quantitative genetics.
Maternal effects occur when characteristics or conditions of the mother influence offspring phenotypes beyond the offspring’s own direct genotype. Learn about maternal genetic and environmental effects, inheritance, heritability, breeding, development, and evolution.
Environmental correlation measures how environmental effects influencing two traits vary together. Learn its formula, relationship with phenotypic and genetic correlation, environmental covariance, heritability, G×E, breeding, and quantitative genetics.
Phenotypic correlation measures how two observable traits vary together. Learn its formula, relationship with phenotypic covariance, genetic correlation, environmental effects, heritability, selection, and quantitative genetics.
Genetic correlation measures how genetic effects influencing two traits vary together. Learn its formula, relationship with genetic covariance, pleiotropy, G-matrix, selection, breeding, and evolution.
Repeatability measures the consistency of repeated trait measurements within individuals. Learn its formula, relationship with heritability, permanent environmental effects, breeding value, selection, and quantitative genetics.
Realized heritability measures heritability from the observed response to selection. Learn its formula, selection differential, additive genetic variance, breeding value, genetic gain, breeding, and evolution.
Heritability describes the proportion of phenotypic variation associated with genetic differences in a population. Learn about broad- and narrow-sense heritability, genetic variance, environmental effects, selection, breeding, and evolution.
Genetic covariance describes how genetic effects influencing two traits vary together. Learn how it relates to genetic correlation, pleiotropy, the G-matrix, selection, breeding, and evolution.
Covariance among relatives measures the similarity of relatives for a trait and helps estimate additive genetic variance, heritability, breeding values, genetic correlations, and the inheritance of complex traits.
Environmental variance describes differences in phenotypes caused by environmental and non-genetic factors. Learn how environmental conditions, G×E interactions, heritability, and quantitative genetics influence trait variation.
Genetic variance describes genetic differences among individuals that contribute to phenotypic variation. Learn about additive, dominance, and epistatic variance, heritability, genetic architecture, selection, breeding, and evolution.
