Genetic population structure of the ground beetle, Pterostichus oblongopunctatus, inhabiting a fragmented and polluted landscape: Evidence for sex-biased dispersal

Malgorzata Lagisz1,2, Kirsten Wolff2, Roy A Sanderson2, Ryszard Laskowski1

1Institute of Environmental Sciences, Jagiellonian University, 31-202 Kraków, Poland
2School of Biology, University of Newcastle, Newcastle upon Tyne, NE1 7RU, UK

Abstract

Ground beetles are an integral and functionally important part of many terrestrial ecosystems. Habitat change often influences population genetic structure of carabid beetles. In this study, genetic variation, population differentiation, and sex-specific dispersal patterns were studied in the forest ground beetle, Pterostichus oblongopunctatus F. (Coleoptera: Carabidae), in a fragmented and metal-polluted landscape to assess the consequences of human-induced changes on the population genetic structure. Genotypic variation at five microsatellite loci was screened in 309 beetles from 21 sample locations around zinc-and-lead smelter in southern Poland. Low levels of genetic differentiation among sampling sites were observed, suggesting high gene flow among populations. A negative correlation was found between levels of genetic differentiation and habitat patch size. No significant effects of metal pollution, in terms of genetic bottlenecks and genetic differentiation, were observed. Analyses revealed weak genetic clustering that is loosely tied to the geographic position of the sampled populations. Several tests of sex-biased dispersal were conducted. Most of them indicated male-biased dispersal. Differing levels of dispersal between females and males resulted in sex-specific spatial genetic patterns. Genetic differentiation was significantly correlated with geographical distance for males, but not for females, who were more diverged locally. Also, the effect of habitat patch size was sex-dependent, supporting the finding of different dispersal patterns between the sexes. This study demonstrated the application of microsatellite markers to answer questions regarding complex interactions between population structure and physical properties of the landscape. In the study system, migration appears to be sufficient to override potential effects of environmental pollution as well as habitat fragmentation. This investigation of population genetic structure indicated, for the first time, male-biased dispersal in carabid beetles.

Keywords: gene flow, microsatellite markers, spatial structure
Abbreviations: AMOVA, analysis of molecular variance; F, the probability that two genes share a common ancestor within a population; FIS, inbreeding coefficient of an individual relative to subpopulation; FST, fixation index (the effect of subpopulations compared to total population); mAIc, mean of genetic assignment index; vAIc, variance of genetic assignment index

Correspondence: losialagisz@yahoo.com
Associate Editor: Zhijian (Jake) Tu was editor of this paper.

Received: 9 April 2008 | Accepted: 4 April 2009 | Published: 13 July 2010

ISSN: 1536-2442 | Volume 10, Number 105

Lagisz M, Wolff K, Sanderson RA, Laskowski R. 2010. Genetic population structure of the ground beetle, Pterostichus oblongopunctatus, inhabiting a fragmented and polluted landscape: Evidence for sex-biased dispersal. Journal of Insect Science 10:105, available online: insectscience.org/10.105


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