The Mechanism of Natural Selection for the Sex Ratio

Abstract

- A population on model is presented which quantifies and extends the mechanism described by R. A. Fisher for the natural selection of the sex ratio. It is shown how the sex ratio should adjust so that the total parental expenditure on the production of males is equal to the total expenditure on the production of females, and that this mechanism can affect the mean of a population''s sex ratio, but not the variance.