THE MEASUREMENT OF EFFECTIVE POPULATION NUMBER

The effective population number can be defined either in terms of the amount of increase in homozygosity inbreeding effective number or the amount of gene frequency drift variance effective number. Under many circumstances these are the same, but not in general. The effective number is considered in terms of an idealized population in which each individual parent has an equal expectation of progeny. The effective number of an actual population is defined as the size of an idealized population with the same amount of inbreeding or random gene frequency drift as the population under consideration. Formulae are given for determining both kinds of effective numbers when the population is monoecious including self fertilization and when there are separate sexes. The formulae are summarized along with special cases of interest. Author