Question

When the allelic frequencies of two generations are different. What happen?

Answer 1

If a population is in a state called Hardy weinberg equilibrium, the frequencies of allelles, or gene versions, and genotypes, or sets of alleles, in that population will stay the same over generations. Mutation, migration,non random mating, natural selection and genetic drift are the mechanisms that effect changes in allele frequencies, and when one or more of these forces are acting , evolution occurs. These can result in the difference in allellic frequency of two generations.