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Environmental and climatic determinants of molecular diversity and genetic population structure in a coenagrionid damselfly.

Wellenreuther M, Sánchez-Guillén RA, Cordero-Rivera A, Svensson EI, Hansson B - PLoS ONE (2011)

Bottom Line: We found low to moderate genetic sub-structuring between populations (mean F(ST) = 0.06, D(est) = 0.12), and an effect of longitude, but not latitude, on genetic diversity.No significant effects of geographic boundaries (e.g. water bodies) were found.Finally, we did not detect any molecular signatures of range expansions or an effect of geographic suitability, although local precipitation had a strong effect on genetic differentiation.

View Article: PubMed Central - PubMed

Affiliation: Department of Biology, Lund University, Lund, Sweden. maren.wellenreuther@biol.lu.se

ABSTRACT
Identifying environmental factors that structure intraspecific genetic diversity is of interest for both habitat preservation and biodiversity conservation. Recent advances in statistical and geographical genetics make it possible to investigate how environmental factors affect geographic organisation and population structure of molecular genetic diversity within species. Here we present a study on a common and wide ranging insect, the blue tailed damselfly Ischnuraelegans, which has been the target of many ecological and evolutionary studies. We addressed the following questions: (i) Is the population structure affected by longitudinal or latitudinal gradients?; (ii) Do geographic boundaries limit gene flow?; (iii) Does geographic distance affect connectivity and is there a signature of past bottlenecks?; (iv) Is there evidence of a recent range expansion and (vi) what is the effect of geography and climatic factors on population structure? We found low to moderate genetic sub-structuring between populations (mean F(ST) = 0.06, D(est) = 0.12), and an effect of longitude, but not latitude, on genetic diversity. No significant effects of geographic boundaries (e.g. water bodies) were found. F(ST)-and D(est)-values increased with geographic distance; however, there was no evidence for recent bottlenecks. Finally, we did not detect any molecular signatures of range expansions or an effect of geographic suitability, although local precipitation had a strong effect on genetic differentiation. The population structure of this small insect has probably been shaped by ecological factors that are correlated with longitudinal gradients, geographic distances, and local precipitation. The relatively weak global population structure and high degree of genetic variation within populations suggest that I. elegans has high dispersal ability, which is consistent with this species being an effective and early coloniser of new habitats.

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Map of I. elegans (n = 22) and                            I. graellsii (n = 4) study                        populations.The geographic range of I. elegans includes Europe with the                        exception of northern Scandinavia, Corsica, Sardinia, Sicily and Malta, and                        the western and southern parts of the Iberian Peninsula where it is replaced                        by its sister species I. graellsii[31]. The range of I.                            elegans further extends to the Middle East, and over much of                        Russia and China [31].
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pone-0020440-g001: Map of I. elegans (n = 22) and I. graellsii (n = 4) study populations.The geographic range of I. elegans includes Europe with the exception of northern Scandinavia, Corsica, Sardinia, Sicily and Malta, and the western and southern parts of the Iberian Peninsula where it is replaced by its sister species I. graellsii[31]. The range of I. elegans further extends to the Middle East, and over much of Russia and China [31].

Mentions: In this study, we investigated the genetic diversity and population structure of a common and wide-ranging insect, the blue tailed damselflyIschnuraelegans (Odonata, Coenagrionidae). This small damselfly species is a well-investigated study system in evolutionary ecology, particularly in terms of mating interactions, sexual selection, female colour polymorphisms, frequency-dependent selection and sexual conflict [19], [20], [21], [22], [23]. Interest in this species has also arisen due to its enigmatic mating system and the presence of a heritable colour polymorphism in females [24], [25] and the rapid evolutionary dynamics that has been observed in natural populations [26], [27]. To investigate the geographic pattern of intraspecific genetic diversity of I. elegans, we investigated the molecular structure of 22 populations over most of the western part of this species' geographical range (spanning 12° in latitude and 38° in longitude; Figure 1), along with four populations of its congeneric sister species I. graellsii. These two sister species are similar in habitat choice and morphology [28], and hybridise in north-western Spain, where they produce fertile offspring [25], [28]. Analyses of DNA sequence variation of the mitochondrial cytochrome b and coenzyme II have shown that the genetic distance between I. elegansand I. graellsiiis only 0.2%, suggesting that these two species are very closely related[25], or alternatively, that long-term on-going hybridization counteracts genetic divergence between I. elegans and I. graellsii[28], [29]. Molecular population diversity of both species was analysed with novel microsatellite markers that we specifically developed for I. elegans. Cross-amplification tests have revealed that these microsatellites are also polymorphic in I. graellsii[30]. The pattern of intraspecific genetic diversity in I. elegans was analysed with particular attention to longitudinal and latitudinal clines. We further investigated if geographic boundaries within the sampling area have led to discontinuities in molecular population structure, since both large water masses and mountains within the sampling area present potential barriers to dispersal. We also tested if geographic distance between populations exhibits an effect on population connectivity (i.e. dispersal) and investigated if we could find evidence for a signature of past historical bottlenecks. Finally, we evaluated several different ecological scenarios by relating environmental factors and their interactions to population specific FST-values of I. elegans, namely the role of range expansion (latitude and longitude), geographic suitability (distance to coast and altitude) and climatic suitability (mean annual temperature and precipitation).


Environmental and climatic determinants of molecular diversity and genetic population structure in a coenagrionid damselfly.

Wellenreuther M, Sánchez-Guillén RA, Cordero-Rivera A, Svensson EI, Hansson B - PLoS ONE (2011)

Map of I. elegans (n = 22) and                            I. graellsii (n = 4) study                        populations.The geographic range of I. elegans includes Europe with the                        exception of northern Scandinavia, Corsica, Sardinia, Sicily and Malta, and                        the western and southern parts of the Iberian Peninsula where it is replaced                        by its sister species I. graellsii[31]. The range of I.                            elegans further extends to the Middle East, and over much of                        Russia and China [31].
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3105071&req=5

pone-0020440-g001: Map of I. elegans (n = 22) and I. graellsii (n = 4) study populations.The geographic range of I. elegans includes Europe with the exception of northern Scandinavia, Corsica, Sardinia, Sicily and Malta, and the western and southern parts of the Iberian Peninsula where it is replaced by its sister species I. graellsii[31]. The range of I. elegans further extends to the Middle East, and over much of Russia and China [31].
Mentions: In this study, we investigated the genetic diversity and population structure of a common and wide-ranging insect, the blue tailed damselflyIschnuraelegans (Odonata, Coenagrionidae). This small damselfly species is a well-investigated study system in evolutionary ecology, particularly in terms of mating interactions, sexual selection, female colour polymorphisms, frequency-dependent selection and sexual conflict [19], [20], [21], [22], [23]. Interest in this species has also arisen due to its enigmatic mating system and the presence of a heritable colour polymorphism in females [24], [25] and the rapid evolutionary dynamics that has been observed in natural populations [26], [27]. To investigate the geographic pattern of intraspecific genetic diversity of I. elegans, we investigated the molecular structure of 22 populations over most of the western part of this species' geographical range (spanning 12° in latitude and 38° in longitude; Figure 1), along with four populations of its congeneric sister species I. graellsii. These two sister species are similar in habitat choice and morphology [28], and hybridise in north-western Spain, where they produce fertile offspring [25], [28]. Analyses of DNA sequence variation of the mitochondrial cytochrome b and coenzyme II have shown that the genetic distance between I. elegansand I. graellsiiis only 0.2%, suggesting that these two species are very closely related[25], or alternatively, that long-term on-going hybridization counteracts genetic divergence between I. elegans and I. graellsii[28], [29]. Molecular population diversity of both species was analysed with novel microsatellite markers that we specifically developed for I. elegans. Cross-amplification tests have revealed that these microsatellites are also polymorphic in I. graellsii[30]. The pattern of intraspecific genetic diversity in I. elegans was analysed with particular attention to longitudinal and latitudinal clines. We further investigated if geographic boundaries within the sampling area have led to discontinuities in molecular population structure, since both large water masses and mountains within the sampling area present potential barriers to dispersal. We also tested if geographic distance between populations exhibits an effect on population connectivity (i.e. dispersal) and investigated if we could find evidence for a signature of past historical bottlenecks. Finally, we evaluated several different ecological scenarios by relating environmental factors and their interactions to population specific FST-values of I. elegans, namely the role of range expansion (latitude and longitude), geographic suitability (distance to coast and altitude) and climatic suitability (mean annual temperature and precipitation).

Bottom Line: We found low to moderate genetic sub-structuring between populations (mean F(ST) = 0.06, D(est) = 0.12), and an effect of longitude, but not latitude, on genetic diversity.No significant effects of geographic boundaries (e.g. water bodies) were found.Finally, we did not detect any molecular signatures of range expansions or an effect of geographic suitability, although local precipitation had a strong effect on genetic differentiation.

View Article: PubMed Central - PubMed

Affiliation: Department of Biology, Lund University, Lund, Sweden. maren.wellenreuther@biol.lu.se

ABSTRACT
Identifying environmental factors that structure intraspecific genetic diversity is of interest for both habitat preservation and biodiversity conservation. Recent advances in statistical and geographical genetics make it possible to investigate how environmental factors affect geographic organisation and population structure of molecular genetic diversity within species. Here we present a study on a common and wide ranging insect, the blue tailed damselfly Ischnuraelegans, which has been the target of many ecological and evolutionary studies. We addressed the following questions: (i) Is the population structure affected by longitudinal or latitudinal gradients?; (ii) Do geographic boundaries limit gene flow?; (iii) Does geographic distance affect connectivity and is there a signature of past bottlenecks?; (iv) Is there evidence of a recent range expansion and (vi) what is the effect of geography and climatic factors on population structure? We found low to moderate genetic sub-structuring between populations (mean F(ST) = 0.06, D(est) = 0.12), and an effect of longitude, but not latitude, on genetic diversity. No significant effects of geographic boundaries (e.g. water bodies) were found. F(ST)-and D(est)-values increased with geographic distance; however, there was no evidence for recent bottlenecks. Finally, we did not detect any molecular signatures of range expansions or an effect of geographic suitability, although local precipitation had a strong effect on genetic differentiation. The population structure of this small insect has probably been shaped by ecological factors that are correlated with longitudinal gradients, geographic distances, and local precipitation. The relatively weak global population structure and high degree of genetic variation within populations suggest that I. elegans has high dispersal ability, which is consistent with this species being an effective and early coloniser of new habitats.

Show MeSH