Consider our discussion of migration-selection balance and a small population where the recessive allele is selected for but immigrants bring in the locally less desirable dominant allele. We often see three equilibrium points for the frequency of the recessive allele. One at q = 0, one at q = a smaller number (e. g., 0.1) and one where q is higher (e. g., q = 0.85). The exact values of these equilibria depend on things like the strength of selection and the immigration rate. Consider just the smaller equilibrium number (using the examples above, q = 0.1, not q = 0). When q is between 0 and this smaller value, what happens to the recessive allele over time and why?
A. The recessive allele will decrease over time, because it is being selected against.
B. The recessive allele will increase over time, because it is being brought in by immigrants.
C. The recessive allele will decrease over time, because it is being swamped by the dominant allele brought in by immigrants.
D. The recessive allele will increase over time, because selection for it is increasing its frequency.
E. The recessive allele will not change.