Speciation in rock-dwelling land snails

Geographic speciation is generally accepted as the most common form of diversification in animals, and it is especially easy to invoke in systems where organisms have low dispersal capability together with fragmented range due to patchy distribution of their habitat. Isolation is often assumed to be the sole explanation for the origin of diversity in these insular settings. As a result, the potential influence of selection and the possible contribution of non-allopatric modes of speciation have often been ignored, and several aspects of the evolutionary process remain unrecognized in such systems. In the focus of our study is the extensive radiation of the Balkan-endemic clausiliid (door- snail) genus Montenegrina. As a rock-dwelling gastropod genus, Montenegrina lives on isolated and scattered rocky outcrops in topographically complex terrain and comprises large numbers of narrow- range, morphologically-distinguishable taxa, providing an excellent system for studying stages and modes of speciation. We plan to analyse a comprehensive sample (each known taxon and populations from almost every known occurrence). As prerequisites for delivering further objectives, we will reconstruct the phylogeny of Montenegrina and carry out a long-needed taxonomic revision using several molecular genetic markers and morphology-based methods. Based on this taxonomic scaffold, we will reconstruct the biogeographic history of the genus and study the relationships between phylogenetic, morphological and ecological divergences. Primary objectives are to shed light on the role of selection and to assess the relative weight of non-allopatric modes of speciation in this rock- dwelling gastropod radiation. The novelty and intellectual merit of the project arises from the integrative approach: It is the first attempt to combine methods of traditional taxonomy, morphometrics, molecular phylogenetics, population genetics phylogeography and niche modeling in a comprehensively sampled, diverse land snail group. Aside from answering fundamental questions about speciation, this project is expected to bring methodological advances in two fields: First, it will lead to new developments in the use of niche models for studying the role of ecology during speciation. And second, Montenegrina will be the first clausiliid taxon for which microsatellite primers will be established, and these newly developed primers enable the application of microsatellite analysis in population genetic studies of other taxa in this species-rich family.

No additional funding sources recorded.