Question

4. Say we have a population, with Ne = 100, containing two alleles, A1 and A2 at frequencies 0.6 and 0.4, respectively. We leave this population alone for 10000 generations (keeping its size constant), then come back to find that the allele frequencies are still 0.6 and 0.4.

a) Explain why this would be evidence that selection is acting in this population.

b) Which genotype would you expect to have the highest fitness in this case? Explain.

Answer 1

A) after 10000 generation still allele frequency is same that is 0.6 and 0.4. This indicate random mating population. No other factors ( immigration, emigration, no selection, mutation etc) are operating. According to Hardy Weinberg law , if a population remain in random mating with no other factors are operating, in that case allele frequency will remain constant from generation to generation. That is why here allele frequency is still same.

B) in random mating population all the genotypes are equally fit. There is no natural selection that makes organism equally like to survive and reproduce.