In simulation you established the fitness of the aa allele a

In simulation, you established the fitness of the aa allele as 0, removing all aa individuals from the breeding population. This may be in the case of a serious genetic disease, but selection is not always so drastic. In the case of coquinas on the beach, white shells may suffer a measurable disadvantage due to higher bird predation, but their fitness is obviously not Some white clams do survive to reproductive age. Suppose predation rates on white clams were not total, but did occur at twice the rate of predation on purple-rayed clams. How would you alter this procedure to simulate a 50% survival rate of the aa genotype? How would you expect this change in the simulation rules to affect the outcome?

Solution

Since in simulation we make a model for the purpose of study and further the relative fitness of a given genotype is basically the ratio of the survival and reproductive rate of a particular genotype. Further the survival rate is the percentage % of the no of individuals that once born survive and reproductive rate will be the average number of offsprings born per individual of a particular genotype. Hence based on the information given in the above question we will have to adjust and change the values of the survival rate and the reproductive rate to  achive higher relative fitness values that are above 0 for the aa genotype. For arriving at 50% survival rate we have to assume that alteast 50% individuals with the aa genotype survive.