Question

Imagine an island archipelago where all of the islands are founded by individuals that are heterozygous at a particular locus. If there is no migration or mutation, and the alleles at that locus are neutral, what do you expect the island populations to look like after many generations?
a) Some island populations will have fixed one allele, and other populations will have fixed the other allele.
b) The populations on every island will have fixed the same allele.
c) The island populations will have high levels of genetic diversity at this locus.
d) We cannot assess the probability of any outcome because genetic drift is a random process.

Answer 1

Answer:

a) Some island populations will have fixed one allele, and other populations will have fixed the other allele.

Explanation:

The founder population for each island is heterozygous for the locus. The absence of any migration and mutation would result in no gene flow or the introduction of new alleles of the locus. Over several generations, one or the other allele will be fixed in the populations depending on the adaptive features imparted by each under the different conditions present on these different islands. Genetic drift may also work on these small founder populations to randomly fix one or the other allele.