Question

Is the rate of evolutionary substitution a function of population size under Kimura's model of molecular evolution? Briefly explain your answer, qualitatively and by reference to Kimura's mathematical demonstration.

Answer 1

ANS. The neutral theory of evulution is proposed by Motoo Kimura. The neutral theory states that there are no fitness differences between almost all of th molecular variation that detected in populations.neutral is the word chosen to describe the lack of fitness differences (functionally equivalent alleles.

2)Amount of genetic variation in a population is determined by a balance between an increase due to mutation,rate =and a decrease due to finite population size(= genetic drift).the neutral theory adopts the perspective that most mutations have little ot no fitness advantage or disadvantage and are therfore selectively neutral.the neutral theory null model makes two majot predictions under the assumption that genetic drift alone determines the fate of new mutations.one predection is the amount polymorphism for sequences sampled within a population one species.divergence fixed genetic differences that accumulate between two completely isolated lineages that were originaly identical when they diverged from a common ancestor.and the polymorphism existence in a population of two or more alleles at one locus.populations with genetic polymorphisms have heterozygosity ,gene diversity or or nucleotide diversity