Optimum proportions selected with unequal sex numbers.

Optimum proportions selected for each sex, giving the maximum selection response up to some specified time, have been investigated. Selection was carried out from a constant number of individuals scored per generation. It has been shown that the maximum response after t generations of selection is obtained when the number of individuals scored and the proportion selected is the same for males and females every generation. Specific situations, where the sex-ratio among scored or breeding individuals or the selected proportion of males or females is taken as given throughout the whole selection process, have been studied, optimum strategies being described in each case. The procedures leading to maximum advance at the selection limit have also been considered in all these situations.