Abstracts - Deutsche Zoologische Gesellschaft

Evolutionary Biology Posters 131P EB.14 - ENDevelopment and possible evolution of first maxillae suction discs in Carp lice(Crustacea, Branchiura); molecular and morphological evidenceOle Sten Möller 1 , Jörgen Olesen 2 , AnneMarié Avenant-Oldewage 3 , Phillip Thomsen 4 , HenrikGlenner 41Allgemeine und Spezielle Zoologie, Universität Rostock; 2 Invertebrate Working Group, ZoologicalMuseum, University of Copenhagen, Denmark; 3 Department of Zoology, University ofJohannesburg, South Africa; 4 Center for Ancient Genetics, Niels Bohr Institute & Department ofBiology, University of Copenhagen, DenmarkThe fish ectoparasites Branchiura (Crustacea) display two different ways of attachment to the fishsurface as adults: the first maxillae are either hooks (Dolops) or suction discs (Argulus, Chonopeltis,and Dipteropeltis). In larval Argulus foliaceus the first maxillae are hooks. In view of the first molecularphylogenetic reconstruction of Branchiura, I discuss the evolutionary scenarios leading tohooks versus suction discs. Specific homologies exist between larval Argulus foliaceus hooks andadult Dolops ranarum hooks; e.g., a distal segment terminating in a double structure: a distal twoparthook (in Argulus) or one hook and an associate spine-like structure (in Dolops). In the phylogeneticreconstruction based on three molecular markers 16S MtrRNA, nuclear 18S and 28S rRNA,D. ranarum is found to be in a sister group position to all other Branchiura, which in this analysisinclude six Argulus and one Chonopeltis sequences. Based on the molecular phylogeny a likelyevolutionary scenario supported by character polarization using the ontogenetic criterion is that theancestral branchiuran used hooks (on the first maxilla) for attachment, as seen in Dolops, of whichthe proximal part was subsequently modified into suction discs in Argulus and Chonopeltis (andDipteropeltis). The sister group relationship of Branchiura and Pentastomida is confirmed based onthe largest taxon sampling until now. No evidence was found for a branchiuran in-group position ofthe Pentastomida.P EB.15 - ENDifferentiation in partner choice between two closely related populations of thehouse mouseInka Montero, Meike TeschkeEvolutionsgenetik, Max Planck Institute for Evolutionary Biology, PlönNon random partner choice could be due to differences in the attractiveness of males, as well as theevolution of different kin recognition characters influencing the odor signals or different ethologicaltraits. Using two separated populations of Mus musculus domesticus, which have been split about3,000 years ago, we are interested in determining whether this recent split is associated with divergencein sexual and social partner choice. We set up a long term experiment in which individuals ofboth populations are tested for partner choice in semi natural environments. Mate choice and successfulreproduction is assessed by paternity tests in the offspring and examining the fitness of thelitters, while patterns of social partner choice is determined using spatial associations as a measurefor preference.