What are the relative roles of genetic drift versus natural selection in generating phenotypic divergence between populations?

Project leader

Funding source

Swedish Research Council - Vetenskapsrådet (VR)

Project Details

Start date: 01/07/2008
End date: 30/06/2010
Funding: 1356000 SEK


There is often great variation in physical appearance between individuals from different populations of the same species. The conventional wisdom is that organisms evolve through gradual changes that arise as individuals become adapted to their environment. This project aims to test the hypothesis that differences also can arise through non-adaptive processes. When there is little variation in heritable traits for natural selection to act upon, as can be the case on islands, non-adaptive divergence due to genetic drift might be an important process. To explore this issue I will study insular populations of voles in the archipelago of Stockholm. These populations show great variation in body sizes, and therefore provide an excellent system for studies of this topic. I will use molecular techniques to compare population differentiations in neutral marker genes and heritable quantitative traits to assess the relative importance of natural selection versus genetic drift in causing divergence between populations. I will also use analyse the genetic structure of the populations to clarify how genetic variability within populations relate to their degree of isolation and population sizes. To test for an adaptive advantage to large body size in terms of the vole’s ability to disperse between islands I will conduct experiments that will compare swimming ability of differently sized voles.

Last updated on 2017-31-03 at 12:57