Professor Schwabl’s research is at the interface of behavioral biology, endocrinology, and evolutionary ecology . Specifically his lab is interested in the regulation of reproduction in relation to the social and physical environment. His current research focuses on female reproductive biology and the consequences of female reproductive decisions for the phenotype and the fitness of the offspring. Understanding the evolutionary significance of such maternal effects requires investigation of proximate regulatory mechanisms and of ultimate fitness consequences. Therefore he studies animals (mainly birds) in their natural environment (including the tropics), conducts controlled laboratory experiments, measures and manipulates hormone levels, quantifies behavior, and estimates fitness. The specific goals of this research program are to understand 1) female reproductive plasticity; 2) effects of female reproductive decisions on anatomy, physiology, development, and behavior of offspring; and 3) evolution and fitness consequences of maternal effects.
Schwabl H., Dowling J., Baldassarre, D., Lindsay, Gahr., M. W. Webster M. 2015. Variation in song system anatomy and androgen levels does not correspond to song characteristics in a tropical songbird. Animal Behaviour, accepted.
Barron, D. G., M. S. Webster, and H. Schwabl. 2015. Do androgens link morphology and behavior to produce phenotype-specific behavioral strategies? Animal Behaviour 100: 116-124.
Schwabl, H., Lindsay, W. R., D. G. Barron, and M. S. Webster. 2014. Endocrine correlates of mate choice and promiscuity in females of a socially monogamous avian mating system with alternative male reproductive phenotypes. Current Zoology 60: 804-815.
Egbert, J.R. , M. F. Jackson, B. D. Rodgers, H. Schwabl. 2013. Between-female variation in house sparrow yolk testosterone concentration is negatively associated with CYP19A1 (aromatase) mRNA expression in ovarian follicles. General and Comparative Endocrinology 183 (2013) 53–62.
Lindsay, W. R., M. S. Webster, & H. Schwabl. 2011. Sexually selected male plumage color is testosterone dependent in a tropical passerine bird, the red-backed fairy-wren (Malurus melanocephalus). PloS One 6:e26067.
Webster, M. S., J. Karubian and H. Schwabl. 2010. Dealing with uncertainty: Flexible reproductive strategies by a tropical passerine bird in an unstable environment. Advances in the Study of Behavior 42: 123-153.
Schwabl, H. & Groothuis, T.G.G. 2010. Maternal effects on behavior. Encyclopedia of Animal Behavior, Eds: M. D. Breed & J. Moore, ISBN: 978-0-08-045337-8, p. 399-411.
Lindsay, W.R., M.S. Webster, C.W. Varian, H. Schwabl. 2009. Androgens are associated with acquisition of bright nuptial plumage and reproductive phenotype in a polymorphic tropical bird. Anim. Behav. 77: 1525-1532.
Partecke, J. & Schwabl H. 2008. Organizational effects of maternal testosterone on reproductive behavior of adult house sparrows. Developmental Neurobiology. Published Online: DOI: 10.1002/dneu.20676.
Groothuis, T.G. G. & H. Schwabl. 2008. Review: Hormone-mediated maternal effects in birds: mechanisms matter but what do we know of them? Philosophical Transactions of the Royal Society of London – Series B: Biological Sciences. 363(1497):1647-1661.
Martin, T.E. & H. Schwabl. 2008. Variation in maternal effects and embryonic development rates among passerine species. Philosophical Transactions of the Royal Society of London – Series B: Biological Sciences. 363(1497):1663-1674.
Schwabl H., M. G. Palacios, and T. E. Martin. 2007. Selection for rapid embryo development leads to higher embryo exposure to maternal androgens among passerine birds. The American Naturalist 170:196-206.
Petrie, M., Schwabl, H., Brande-Lavridsen, N. and Burke, T. 2001. Sex differences in avian yolk hormone levels. Nature 412: 498.
Schwabl, H., D. Mock, and J. Gieg. 1997. A hormonal mechanism of parental favouritism. Nature 386: 231.
Schwabl, H. 1993. Yolk is a source of maternal testosterone for developing birds. Proc. Natl. Acad. Sci. USA 90: 11439-11441.