Question

A population of Mauna Loa Silversword exists as three separate populations: Population A and B are closely linked such that many individuals migrate between the populations each year. Population C is very far and isolated from A and B such that few, if any, migration occurs.

If each population is experiencing natural selection in favor of different alleles, what might we expect to be true of the allele frequencies in each of these populations when compared to each other? Explain. Note: assume that no random evolutionary forces are operating. (6 points)

Answer 1

The population A and B have constant inter-mixing between them. Hence both of these populations will evolve together and exhibit the same allele frequencies. This is because the two populations are growing together and are not separated by any barrier.

The population C is separated from A and B populations. Also, this population hardly exhibits migration with A and B. Hence the selection pressure experienced by A and B will be completely different from that experienced by C.

Thus, the allele frequencies of population C will be completely different from populations A and B, and given enough time, the population C might even diverge off to become a different species that will no longer be able to interbreed with populations A and B.