Table 1.
Key terms and components relating to adaptive accuracy of individuals and populations
| Term | Definition | Derivation/symbol |
|---|---|---|
| Adaptive optimum | Predefined or estimated point in phenotypic space yielding maximum fitness | θ, E[θ] |
| Variance in adaptive optimum | Population variance in value of optimum | Var[θ] |
| Individual: adaptive inaccuracy | A genotype's average squared phenotypic distance from optimum | s(zT – E[θ])2 + sVar[θ] + sVd |
| Population: maladaptation (population inaccuracy or load) | A population's average squared phenotypic distance from optimum | s(E[z]–Eθ[θ])2 + sVT + sVar[θ] + sE[Vd] |
| Genotypic target | Expected phenotype produced by a genotype, i.e. mean phenotype across a range of environments | zT |
| Mean genotypic deviation from optimum | The difference between the population mean and the optimum | zT – E[θ] |
| Phenotypic imprecision | Phenotypic variance around the genotypic target, caused by developmental noise, environmental variance, etc. | Vd |
| Population mean deviance (from optimum) | The difference between the population mean and the optimum | E[z] – Eθ[θ] |
| Population imprecision | Phenotypic variance in population caused by genetic variation (genotypic target variance), environmental variance, and developmental noise (phenotypic imprecision) | VT + E[Vd] |