It has been shown theoretically that sympatric speciation can occur if intraspecific competition is strong enough to induce disruptive selection. However, the plausibility of the involved processes is under debate, and many questions on the conditions for speciation remain unresolved. For instance, is (strong) disruptive selection sufficient for speciation? Which role do genetic architecture and initial composition of the population play? How strong must assortative mating be, so that a population can split in two? These are some of the issues we address here. We investigate a diploid multilocus model of a quantitative trait that is under frequency-dependent selection caused by a balance of intraspecific competition and frequency-independent stabilizing selection. This trait also acts as mating character for assortment. It has been established previously that speciation can occur only if competition is strong enough to induce disruptive selection. We find that speciation becomes more difficult for very strong competition, because then extremely strong assortment is required. Thus, speciation is most likely for intermediate strengths of competition, where it requires strong, but not extremely strong assortment. For this range of parameters, however, it is not obvious how assortment can evolve from low to high levels because with moderately strong assortment less genetic variation is maintained than under weak or strong assortment, sometimes none at all. In addition to the strength of frequency-dependent competition and assortative mating, the roles of the number of loci, of the distribution of allelic effects, of the initial conditions, of costs to being choosy, of the strength of stabilizing selection, and of the particular choice of the fitness function are explored. A multitude of possible evolutionary outcomes is observed, including loss of all genetic variation, splitting in two to five species, as well as very short and extremely long stable limit cycles.

• Date and place of birth: June 13, 1956, Vienna, Austria
• Citizenship: Austria
• Matura (university-entrance diploma), Bundesgymnasium Berndorf, 1974
• Dr. phil. (PhD), Mathematics, University of Vienna, 1979
• Mag. rer.nat. (MS), Mathematik und Physik Lehramt (diploma for high school teacher), University of Vienna, 1982

• 1980-1981: Postdocs at Department of Mathematics and Department of Theoretical Chemistry, University of Vienna
• 1982-1988: Assistent Professor, Department of Mathematics, University of Vienna
• 1985: Authorization as Universitätsdozent (Venia Docendi, university lecturer) for Mathematics, University of Vienna
• 1988-1996: Assistant Professor with Tenure, Department of Mathematics
• 1991: Research fellow, Division of Animal Production, CSIRO, Sydney, Australia
• 1992-1993: Courtesy Full Professor, University of Oregon, Eugene, OR (funded by Max-Kade-Foundation, New York)
• 1994-2002: Several short-term contracts as a visiting researcher at the International Institute of Applied Systems Analysis (IIASA), Laxenburg, Austria
• 1996 - : Associate Professor (Ao. Univ. Prof.), Department of Mathematics, University of Vienna
• 2004-2008: Visiting Scholar, Program for Evolutionary Dynamics, Harvard University

Research Areas
• Mathematical biology, with special emphasis on population genetics, quantitative genetics and evolutionary biology
Services
• Member of the Editorial Board of the Journal of Mathematical Biology (since 2001)
• Member of the Editorial Board of the Journal of Theoretical Biology (since 2007)
• Reviewing Editor of the Journal of Evolutionary Biology (2002 - 2006)
• Member of Board of Directors of “The Konrad Lorenz Institute for Evolution and Cognition Research” (since 2003)
• Austrian representative on the ConGen (conservation genetics) steering committee of the European Science Foundation (2004 – 2009)
• Co-convenor of the Symposium “Theoretical Population Genetics” at the International Congress of Genetics in Melbourne, Australia (2003)
• Organizer of several workshops and symposia
• Member of the SAB of the CIBIV (Vienna) and the FSPM (Bielefeld)
• Reviewer for numerous scientific journals including Nature and Science, as well as for various Science Foundations (e.g., NSF, Volkswagenstiftung, BBRSC)

Recent Research Grants (as PI)
• Fluctuation analysis and the Luria-Delbrück distribution (Austrian Science Foundation, FWF, 2001-2004, € 78.600)
• Genetic models of frequency-dependent selection (Austrian Science Foundation, 2003-2006, € 108.100)
• A simulation approach to the evolution of the G matrix (NSF, 2005-2008, US$ 95.000; US-based PIs: S.J. Arnold, A.G. Jones)
• Mathematics and Evolution: Mathematical and Statistical Analysis of Ecological and Genetic Diversity (Vienna Science, Research, and Technology Foundation (WWTF), 2005-2008, € 500.000)

• Bürger, R., Willensdorfer, M., and Schneider, K.: The conditions for speciation through
  intraspecific competition. Evolution 60, 2185-2206 (2006), pdf

• Bürger, R., and Schneider, K.: Intraspecific competitive divergence and convergence under assortative mating. Amer. Natur. 167, 190-205 (2006), pdf

• Schneider, K., and Bürger, R.: Does competitive divergence occur if mating is costly? J. Evol. Biology 19, 570-588 (2006) pdf

• Prof. Dr. Reinhard BÜRGER
  Department of Mathematics, University of Vienna, Nordbergstrasse 15, UZA 4, A-1090 Vienna, Austria
  • Phone: +43-1-4277 50631; Fax: +43-1-4277 9506
  • Email: reinhard.buerger@univie.ac.at
  • Web: http://mailbox.univie.ac.at/Reinhard.Buerger