Abstract

Isolation-by-distance (IBD) is a widely used model explaining population structure and how gene flow decreases with increasing distance It is biologically intuitive that populations which rarely exchange individuals should drift apart genetically However, the model is based on the assumptions that populations are large, equal in size and stable over time conditions that are unlikely to occur in natural conditions. The model has been challenged in the past, for example, in the light of metapopulations or variance in reproductive success. However, an appraisal of the assumption of a large and stable population size per se is lacking We investigate the robustness of the results concerning IBD patterns when smaller and fluctuating population sizes, or differences in population size are allowed Through computer simulations we show that allowing for different population sizes and random fluctuations lead to unpredictable patterns regarding the results concerning gene flow and IBD A pattern of IBD could be the result of high gene flow or no gene flow at all, depending on how populations differ in size and how they fluctuate Adding environmental noise (white, red and blue noise corresponding to random, positive and negative autocorrelation respectively) gives even more unpredictable results concerning patterns of IBD. Our results have important implications for genetic and conservation research Interpreting an IBD pattern, or lack thereof, is not as easy as earlier thought and needs to be more thoroughly explored (C) 2010 Elsevier B V All rights reserved

Keywords

Isolation-by-distance; Wright's Island model; Effective population size; Stepping-stone model; F(ST); Computer simulations

Published in

Ecological Informatics
2010, Volume: 5, number: 3, pages: 167-172
Publisher: ELSEVIER SCIENCE BV

UKÄ Subject classification

Ecology
Genetics
Zoology


Publication identifier

DOI: https://doi.org/10.1016/j.ecoinf.2009.12.003

Permanent link to this page (URI)

https://res.slu.se/id/publ/67075