This dialog box let you change the rate of mutation in the model.
This rate is for the moment constant in time and along the genome. If a mutation occurs, a new alleles is sampled randomly from the allelic pool. For the sake of computation time, we do not actually calculate the probability that a mutation occurs at each allele of each locus, instead we calculate the probability that nu mutation at all occurs in an individual. One minus this probability represents the probability that at least one mutation occurs, however the risk for having more than one mutation in an individual is extremely small in the range of considered mutation rates (say [10-3, 10-7]).