Natural Selection, Mutation, and Fitness

Abstract

This problem is an extension of the genetics models discussed in the previous chapter. Here we introduce survival and fertility rates for the genotypes and combine these rates to form a fitness measure. Together with mutation, these effects consort to give the new genotype frequencies. Geneticists and conservation biologist think the existence of the heterozygote, the AB genotype, is a measure of health of the system of geneotypes. The strength of its presence is sometimes referred to as hybrid vigor and is obviously desired because it carries both alleles.

There is such an unerring power at work, or Natural Selection, which selects exclusively for the good of each organic being. Darwin, Letters, 1857