Biology Questions

1. Describe the interplay between gene flow, genetic drift, and selection. Under what

circumstances does one overwhelm the others? Selection can affect allele frequencies at

loci affecting fitness, but can selection also limit gene flow at unlinked neutral loci?

2. Kimura’s equation (k = µ) provides a powerful prediction for neutral genetic variation.

However, this prediction may not hold for neutral regions linked to regions that are

subjected to selection. How might background selection and rates of recombination affect

the substitution rates for neutral alleles?

3. How can expectations from coalescence theory allow us to detect the effects of selection?

Describe neutrality tests including the Ewens-Watterson and Tajima’s D tests. How can

these tests be confounded by violations of the assumption of constant population size?

How might we distinguish the effects of historical bottlenecks from the effects of

selection?

4. What can variation in levels of genomic differentiation (i.e. speciation islands, FST

outliers) tell us about the effects of selection during divergence among lineages? What

else besides selection can cause FST outliers? What would be a good way to confirm that

these genomic regions were responsible for adaptation to different habitats?