Detailseite
Projekt
Coevolution in simple and complex host-parasite systems. CLUSTER: "Evolutionary genetics of three-spined stickleback - parasite interactions"
Antragsteller
Professor Dr. Theo Bakker
Fachliche Zuordnung
Evolution, Anthropologie
Förderung
Förderung von 2009 bis 2014
Projektkennung
Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 132033873
This project extends and builds upon the results of the phase I project (Bakker BA2885/3-1: Coevolution in simple and complex host-parasite systems), in which a phylogeographic analysis using microsatellites of three-spined sticklebacks, Gasterosteus aculeatus, and one of its parasites with a direct life cycle, the ectoparasitic monogenean Gyrodactylus spp., and one with a complex life cycle, the digenean trematode Diplostomum spp. that uses birds as final hosts, of numerous isolated lakes on the island of North Uist, Outer Hebrides, Scotland was performed. Using fish from one of the populations with well-developed breeding coloration, experimental infections in the laboratory using a full-sib/half-sib breeding design were done. Male breeding coloration and reproductive behaviour were quantified. This dataset will give information about the evolvability of host resistance and the role of sexual selection in the evolution of host resistance. In the phase II project the emphasis will lie on the ecology of host-macroparasite interactions in this system and variation in parasite infectivity. The lakes on North Uist are of two distinguished habitat types: on the east and central parts of the island the lakes are tea-stained and acid while on the west part the lakes are clear and alkaline. Ecological influences on host-macroparasite interactions will be studied on three different levels. First, the phylogeographic dataset of sticklebacks and their Gyrodactylus and Diplostomum parasites of the phase I project will be extended and related to ecological variables like water quality (pH, visibility) and fish population size as a proxy for genetic variability. This analysis will give insights into ecological constraints on host-parasite coevolution. Second, experimental infections of lab-reared full-sib/half-sib progeny from a population with hardly developed, drab breeding coloration will, compared to similar experiments with colourful males in the phase I project, illustrate ecological constraints in the role of sexual selection in the evolution of host resistance. Third, lab-reared progeny of one of the stickleback populations will be exposed to parasites from different lochs using local, loch-specific water in order to establish interpopulational variation in parasite infectivity. This experiment will be done with Gyrodactylus and, when enough snails that shed metacercariae can be collected in the lochs, also with Diplostomum. Variation in infectivity will be related to ecological factors like water quality (pH, visibility), fish population size, and the elaboration of male breeding coloration. Together, the three different approaches will increase our understanding of the role of ecology in the evolution of host-parasite interactions.
DFG-Verfahren
Schwerpunktprogramme
