Heinz Richner University of Bern, Zoology Institute - Evolutionary Ecology, CH Title Host-parasite interactions, maternal effects, and avian life histories Abstract Avian life histories are shaped by the co-evolutionary arms race with parasites where both the hosts and the parasites have developed sophisticated strategies and counterstrategies. As a consequence, both the harm that may arise from parasites and the hosts' responses are not readily apparent purely from observations. It requires experimentation at relevant ecological and temporal scales. This will be first illustrated by our long-term experimental studies on the GreatTit. Second, many ectoparasite species are nest-based hematophageous arthropods and thus directly affect the nestlings, but indirectly also the parents via their responses to the parasite- modulated conditions. Maternal responses transferred via the egg to the offspring include modulation of immunoglobulins, hormones, and potentially also carotenoids. Experiments show that the maternal effects greatly enhance offspring survival and reproductive performance, but also point to the trade-offs involved in strategic parasite control. CV Studied biology at University of Zurich, post-docs in Scotland and eastern Africa, Science Foundation Research Professor at University of Lausanne until 1991, since 1992 Professor at University of Bern, with guest professorships at the University of Santa Barbara, California, and Brisbane, Australia. Most work on bird-parasite interactions and life history evolution, but also on resolution of parent-offspring conflict, using field experiments as a main approach to understand selection on life-history traits at relevant ecological scales. (for a full CV see: http://evolution.unibe.ch/short_cv.htm) Selected recent publications Tschirren B., Fitze P.S. & Richner H. (2007): Maternal modulation of natal dispersal in a passerine bird: an adaptive strategy to cope with parasitism? American Naturalist 169: 87-93 Tanner M., Koelliker M. & Richner H. (2007): Parental influence on sibling rivalry in great tit (Parus major) nests. Animal Behaviour (in press). in press Fitze P.S., Tschirren B., Gasparini J. & Richner H. (2007): Carotenoid-based plumage colors and immune function: Is there a trade-off for rare carotenoids? American Naturalist 169, S137-S144. Tschirren B. & Richner H. (2006): Parasites shape the optimal investment in immunity. Proceedings of the Royal Society of London 273: 1773-1777. Tschirren B., Richner H. & Schwabl H. (2004): Ectoparasite-modulated deposition of maternal androgens in great tit eggs. Proceedings of the Royal Society of London 271, 1371-1375. Fitze, P.S., Clobert J. & Richner H. (2004): Long-term life-history consequences of ectoparasite-modulated growth and development. Ecology 85: 2018-2026. Kölliker, M. & Richner H. (2004) Navigation in a cup: chick positioning in great tit (Parus major) nests. Animal Behaviour 68:1005-1012. Institution address Heinz Richner University of Bern, Zoology Institute - Evolutionary Ecology Lab Baltzerstrasse 6 3012 Bern Switzerland heinz.richner@esh.unibe.ch http://evolution.unibe.ch