Interaction between selection and segregation ratios with redefined concept of fitness differentials

Abstract

Taking into account the redefined concept of fitness differentials among the genotypes, natures of equilibria of models of differential selection in the two sexes under random mating with Mendelian segregation as well as with segregation distortion have been analyzed. Two cases of real interest, where different genes are favored in the two sexes and where overdominance is involved, have been investigated. It has been illustrated through graphical representation that the degree of dominance over the sexes (mainly comparing the heterozygous fitnesses in males and females) is a function of equilibrium region. The considered framework of the one locus model unveils most important result that, generally, above the value of Mendelian segregation, prone to arising of single stable polymorphic equilibrium increases.