Table 1.

Symbols and notation.

Symbol	Meaning
N	Population size
ϕ	Phenotype of an individual
ϕo	Mean phenotype of an individual's offspring
δ	ϕo - ϕ
$\widehat{\overline{\delta }}$	Expected mean value of δ in the population
w	Fitness of an individual
$\tilde{w}$	Expected fitness in the current environment
fϕ	Frequency of phenotype ϕ in the population
Ω	$\frac{w}{\overline{w}}$ conditional on $\overline{w}$ ≠ 0
H($\overline{w}$)	Harmonic mean of $\overline{w}$
μi(w)	ith central moment of w
$\overline{X}$ or Ave (X)	Average value of X in population
$\widehat{X}$ or E(x)	Expected value of random variable X