A positive correlation between genetic differentiation and geographic distance (isolation by distance) is expected from what type of model?

Question

I think it is B, I tried googling it, but I am very confused.

A) Wright-Fisher Model with Migration

B) Continent-Island Model of Migration

C) Stepping-Stone Models

D) Isolation-with-Migration Models

Answer 1

Hi Kiley, the answer to this would be A) the Wright-Fisher Model with Migration. The Wright-Fisher Model is used in genetics to help explain genetic drift within populations. Genetic drift is when certain alleles in a population become either fixed or lost throughout generations of mating, and this drifting occurs more rapidly in smaller populations. When you add isolation by distance into the equation, the population size then depends on population density (how many people are available in the area for mating). This isolation causes individuals to mate within smaller populations, and when there are smaller populations, genetic drift will occur faster. Genetic differentiation, such as genetic drift, occurs when there is restricted gene flow within populations. This is most presently seen in smaller populations, such as those isolated by distance. Hope this helps!