Research: Evolution of megadiverse faunas, systematics and evolution of aquatic Coleoptera, molecular phylogenetics, aquatic insects of Papua Neu Guinea and training of local conservation biologists
Research: Systematics, ecology and biology of parasitoid wasps (Hymenoptera: Braconidae, Ichneumonidae), especially the subfamily Microgastrinae; DNA barcoding applied to taxonomy; Biodiversity inventories with emphasis on the Canadian fauna; Biological control
Research: Studying the morphological effects of potential habitat and character displacement in a Neotropical lizard (Anolis) following invasion by a congener
Research: Freshwater fishes of West- and Central Africa and of the Indonesian Island of Sulawesi: Systematics, phylogeny, biogeography, diversity und speciation. Diversity of Bavarian fishes