Habel, Jan Christian Dem Fachbereich VI (Geographie/Geowissenschaften) der Universität Trier Zur Erlangung des akademischen Grades Doktor der Naturwissenschaften (Dr. rer. Nat.) eingereichte Dissertation Einfluss von Naturfaktoren und Flächennutzungswandel auf die genetische Struktur xerothermer Tierarten in der Region Trier Betreuender: Juniorprofessor Dr. rer nat. Thomas Schmitt 22.5.2006 The influence of natural factors and landuse changes on the genetic structure of xerothermic animals in the region of Trier by Jan Christian Habel (Dipl. env. Sc.) University of Trier, Geosciences (FB VI), Biogeography, Germany Dissertation for the degree of Doctor of natural sciences submitted to the University of Trier (Germany) Declaration I declare that this thesis, composed by myself and embodying work done by myself. This thesis has not been accepted in any previous application for a higher degree. All sources of references and quotations have been duly acknowledged. I have personally designed laboratory work, collected and analysed data, developed the discussion of results; the idea of this work was developed by Junior Professor Dr. Thomas Schmitt, my supervisor. May, 2006 Contributions Supervised by: Junior Professor Dr. Thomas Schmitt University Trier, Biogeography, Div. Molecular Biogeography, Germany Cover and format designed by Micha Heigl and me. Summary Summary The fragmentation of landscapes has an important impact on the conservation of biodiversity. The genetic diversity is an important factor for a population’s viability, influenced by the landscape structure. However, different species with differing ecological demands react rather differently on the same landscape pattern. To address this feature, we studied ten xerothermophilous butterfly species with differing habitat requirements (habitat specialists with low dispersal power in contrast to habitat generalists with low dispersal power and habitat generalists with higher dispersal power). We analysed allozyme loci for about 10 populations (à 40 individuals) of each species in a western German study region with adjoining areas in Luxemburg and north-eastern France. The genetic diversity and genetic differentiation between local populations was discussed under conservation genetic aspects. For generalists we detected a more or less panmictic structure and for species with lower abundance and sedentarily behaviour the effect of isolation by distance. On the other hand, the isolation of specialists was mostly reflected by strong genetic differentiation patterns between the investigated populations. Parameters of genetic diversity were mostly significantly higher in generalists, compared to specialists. Substructures within populations as an answer of low intrapatch migration, low population densities and high population fluctuations could be shown as well. Aspects of landscape history (the historical distribution of habitats resulting of the presence of limestone areas) and the changes of extensive sheep pasturing and the loss of potential habitats in the last few decades (recent fragmentation) are discussed against the gained genetic data- set of the ten butterflies. Contents Contents 1. Introduction ...................................................................................... 1 2. Material and Methods....................................................................... 7 2.1. The study area................................................................................... 7 2.2. The investigated study species ......................................................... 8 2.3. Genetic analysis.............................................................................. 16 2.4. Analysis of population ecology...................................................... 17 3. Low genetic differentiation and high dispersal ability coincide in the widespread butterfly species Melanargia galathea.................. 19 3.1. Results ............................................................................................ 19 3.2. Discussion....................................................................................... 23 Excursus I Genes in space and time: The influence of climatic changes in Europe shown on the Melanargia galathea / M. lachesis species complex................................................................ 26 4. Generalist versus Specialist: the genetic consequence of differing ecological demands ......................................................... 29 4.1. Results ............................................................................................ 29 4.2. Discussion....................................................................................... 32 Excursus II Africa to Europe The African origin of “European” species............................................................................................. 36 5. Not adapted to live in isolation: The genetic response to recent habitat fragmentation and low population densities in three Zygaenids ....................................................................................... 39 5.1. Results ............................................................................................ 39 5.2. Discussion....................................................................................... 43 Excursus III Eastern Europe meets Western Europe: Hybridisation of two lineages in Zygaena carniolica................................................ 48 6. Strongly diverging population genetic patterns of three skipper species: isolation, restricted gene flow and panmixis .................... 51 6.1. Results ............................................................................................ 51 6.2. Discussion....................................................................................... 55 Excursus IV Natural selection ................................................................ 60 7. Well adapted to be expansive or sedentary: The genetic response on dispersal behaviour in two Lycaenids ....................................... 63 7.1. Results ............................................................................................ 63 7.2. Discussion: ..................................................................................... 67 Excursus V A biodiversity hotspot ......................................................... 69 8. Conclusion...................................................................................... 71 9. Evolution… .................................................................................... 73 10. Acknowledgement.......................................................................... 74 11. References ...................................................................................... 76 12. Appendix ........................................................................................ 96 Contents Figures: Figure 1.1: Relationship between the ecological potency of species and its extinction-probability. ........................................................................................................1 Figure 1.2: Species model; ten genetically analysed butterflies........................................5 Figure 2.1: Study area in western Germany and adjoining France and Luxemburg..........7 Figure 2.2: The investigated species classified by habitat requirements and dispersal behaviour............................................................................................................................9 Figure 2.3: Population density and population fluctuation levels in the three investigated Zygaena species. ..........................................................................................10 Figure 3.1: The geographical location of the 17 sample stations of Melanargia galathea............................................................................................................................19 Figure 3.2: Neighbour-joining dendrogram based on the genetic distances....................21 Figure 3.3: Correlation between the geographical distances and the respective genetic distances...............................................................................................................22 Figure 3.4: Map of the study area with the four study sites of Melanargia galathea......23 Figure 4.1: Geographical locations of the ten sample stations of Melanargia galathea and Melitaea aurelia in Germany, France and Luxemburg...............................29 Figure 4.2: Correlation between the geographical distances and the respective genetic distances...............................................................................................................32 Figure 5.1: The geographical location of the 14 sample stations of three Zygaena species in Germany, France and Luxemburg. ..................................................................40 Figure 5.2: Five parameters of genetic diversity for all populations analysed of Zygaena viciae, Zygaena viciae and Zygaena carniolica in Germany, France and Luxemburg. ......................................................................................................................42 Figure 6.1: Location of the fourteen sample stations in western Germany and adjoining France and Luxemburg.....................................................................................51 Figure 6.2: Correlation between the geographical distances and the respective genetic distances...............................................................................................................55