Natural Selection and Mutation

Abstract

The problem in this chapter is an extension of the genetics model of the previous chapter. Given the frequency of appearance of two alleles, A and B, the previous model randomly selected and combined these alleles into three possible genotypes: AA, AB, and BB, whose frequency of appearance is predicted by the Hardy-Weinberg law. In this chapter, we incorporate the law directly and then allow the three genotypes to break up into alleles again, after each genotype undergoes its own fertility and survival rate. Each allele also has a tendency to mutate into the other type before recombining into the new genotypes. The survival and fertility rates combine to form a fitness measure and these two effects consort to give the new genotype frequencies.