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Alpine crossroads or origin of genetic diversity? Comparative phylogeography of two sympatric microgastropod species.

Weigand AM, Pfenninger M, Jochum A, Klussmann-Kolb A - PLoS ONE (2012)

Bottom Line: Consequently, we identify the Alpine Region as a significant 'hot-spot' for the formation of genetic diversity within European Carychium lineages.Passive dispersal via anthropogenic means best explains the presence of transatlantic European Carychium populations on the Azores and in North America.We conclude that passive (anthropogenic) transport could mislead the interpretation of observed phylogeographical patterns in general.

View Article: PubMed Central - PubMed

Affiliation: Department of Phylogeny and Systematics, Goethe University, Frankfurt am Main, Hesse, Germany. A.Weigand@bio.uni-frankfurt.de

ABSTRACT
The Alpine Region, constituting the Alps and the Dinaric Alps, has played a major role in the formation of current patterns of biodiversity either as a contact zone of postglacial expanding lineages or as the origin of genetic diversity. In our study, we tested these hypotheses for two widespread, sympatric microgastropod taxa--Carychium minimum O.F. Müller, 1774 and Carychium tridentatum (Risso, 1826) (Gastropoda, Eupulmonata, Carychiidae)--by using COI sequence data and species potential distribution models analyzed in a statistical phylogeographical framework. Additionally, we examined disjunct transatlantic populations of those taxa from the Azores and North America. In general, both Carychium taxa demonstrate a genetic structure composed of several differentiated haplotype lineages most likely resulting from allopatric diversification in isolated refugial areas during the Pleistocene glacial periods. However, the genetic structure of Carychium minimum is more pronounced, which can be attributed to ecological constraints relating to habitat proximity to permanent bodies of water. For most of the Carychium lineages, the broader Alpine Region was identified as the likely origin of genetic diversity. Several lineages are endemic to the broader Alpine Region whereas a single lineage per species underwent a postglacial expansion to (re)colonize previously unsuitable habitats, e.g. in Northern Europe. The source populations of those expanding lineages can be traced back to the Eastern and Western Alps. Consequently, we identify the Alpine Region as a significant 'hot-spot' for the formation of genetic diversity within European Carychium lineages. Passive dispersal via anthropogenic means best explains the presence of transatlantic European Carychium populations on the Azores and in North America. We conclude that passive (anthropogenic) transport could mislead the interpretation of observed phylogeographical patterns in general.

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Potential distribution models of Carychium minimum and C. tridentatum.Shown are reconstructions for the bioclimatic conditions in present Europe (A, B) and during the European Last Glacial Maximum (LGM) approximately 21,000 years before present (C, D). Potential distribution is marked in black; triangles indicate the location of molecularly confirmed presence points obtained from this study.
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pone-0037089-g005: Potential distribution models of Carychium minimum and C. tridentatum.Shown are reconstructions for the bioclimatic conditions in present Europe (A, B) and during the European Last Glacial Maximum (LGM) approximately 21,000 years before present (C, D). Potential distribution is marked in black; triangles indicate the location of molecularly confirmed presence points obtained from this study.

Mentions: The ‘present-Europe’ models for CM and CT demonstrate a wide area of potential distribution for each taxon (Fig. 5). Except for parts of the southern Mediterranean Peninsulas (Iberian Peninsula, Italian Peninsula, Balkan area) and regions of Scandinavia, the European mainland exhibits suitable bioclimatic conditions. Moreover, model outputs for both taxa imply a mainly sympatric distribution. Our own sampling results yielded a sympatric occurrence of CM and CT at 24% of all localities. Beyond this, model runs suggest CM occurring more to the North and East of Europe (e.g. Baltic states), whereas CT can inhabit regions slightly more to the West (e.g. Brittany, Galicia).


Alpine crossroads or origin of genetic diversity? Comparative phylogeography of two sympatric microgastropod species.

Weigand AM, Pfenninger M, Jochum A, Klussmann-Kolb A - PLoS ONE (2012)

Potential distribution models of Carychium minimum and C. tridentatum.Shown are reconstructions for the bioclimatic conditions in present Europe (A, B) and during the European Last Glacial Maximum (LGM) approximately 21,000 years before present (C, D). Potential distribution is marked in black; triangles indicate the location of molecularly confirmed presence points obtained from this study.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3351404&req=5

pone-0037089-g005: Potential distribution models of Carychium minimum and C. tridentatum.Shown are reconstructions for the bioclimatic conditions in present Europe (A, B) and during the European Last Glacial Maximum (LGM) approximately 21,000 years before present (C, D). Potential distribution is marked in black; triangles indicate the location of molecularly confirmed presence points obtained from this study.
Mentions: The ‘present-Europe’ models for CM and CT demonstrate a wide area of potential distribution for each taxon (Fig. 5). Except for parts of the southern Mediterranean Peninsulas (Iberian Peninsula, Italian Peninsula, Balkan area) and regions of Scandinavia, the European mainland exhibits suitable bioclimatic conditions. Moreover, model outputs for both taxa imply a mainly sympatric distribution. Our own sampling results yielded a sympatric occurrence of CM and CT at 24% of all localities. Beyond this, model runs suggest CM occurring more to the North and East of Europe (e.g. Baltic states), whereas CT can inhabit regions slightly more to the West (e.g. Brittany, Galicia).

Bottom Line: Consequently, we identify the Alpine Region as a significant 'hot-spot' for the formation of genetic diversity within European Carychium lineages.Passive dispersal via anthropogenic means best explains the presence of transatlantic European Carychium populations on the Azores and in North America.We conclude that passive (anthropogenic) transport could mislead the interpretation of observed phylogeographical patterns in general.

View Article: PubMed Central - PubMed

Affiliation: Department of Phylogeny and Systematics, Goethe University, Frankfurt am Main, Hesse, Germany. A.Weigand@bio.uni-frankfurt.de

ABSTRACT
The Alpine Region, constituting the Alps and the Dinaric Alps, has played a major role in the formation of current patterns of biodiversity either as a contact zone of postglacial expanding lineages or as the origin of genetic diversity. In our study, we tested these hypotheses for two widespread, sympatric microgastropod taxa--Carychium minimum O.F. Müller, 1774 and Carychium tridentatum (Risso, 1826) (Gastropoda, Eupulmonata, Carychiidae)--by using COI sequence data and species potential distribution models analyzed in a statistical phylogeographical framework. Additionally, we examined disjunct transatlantic populations of those taxa from the Azores and North America. In general, both Carychium taxa demonstrate a genetic structure composed of several differentiated haplotype lineages most likely resulting from allopatric diversification in isolated refugial areas during the Pleistocene glacial periods. However, the genetic structure of Carychium minimum is more pronounced, which can be attributed to ecological constraints relating to habitat proximity to permanent bodies of water. For most of the Carychium lineages, the broader Alpine Region was identified as the likely origin of genetic diversity. Several lineages are endemic to the broader Alpine Region whereas a single lineage per species underwent a postglacial expansion to (re)colonize previously unsuitable habitats, e.g. in Northern Europe. The source populations of those expanding lineages can be traced back to the Eastern and Western Alps. Consequently, we identify the Alpine Region as a significant 'hot-spot' for the formation of genetic diversity within European Carychium lineages. Passive dispersal via anthropogenic means best explains the presence of transatlantic European Carychium populations on the Azores and in North America. We conclude that passive (anthropogenic) transport could mislead the interpretation of observed phylogeographical patterns in general.

Show MeSH
Related in: MedlinePlus