In 1990 my life changes in three dramatic ways. I have worked on fairy-wrens ever since, seeking an answer to the centrally important question of the benefits that females obtain from discrimination among mates, and the implications of those benefits for understanding the maintenance of genetic variation. I am interested in the evolution of life histories, complex mating systems, and gender and sex in animal societies, and my favourite study animals are birds, dasyurid marsupials and rodents. Our primary study system is the superb fairy-wren Malurus cyaneus , which combines cooperative breeding with extreme cuckoldry, so that young are typically raised by males to which they are completely unrelated. We are also interested in the evolution of reversed sex dimorphism in raptors and eclectus parrots, in which females are larger or brighter than males.
Parents typically produce offspring of two completely distinct sorts- males and females.
We have been interested in the development of molecular techniques that allow the gender of young to be determined at a very early age. In the past I have worked on sex allocation in marsupials, and particularly in Antechinus . Senescence and semelparity. Dasyuridae and Didelphidae suffer from an unexplained evolutionary predisposition to post-reproductive senescence, that in its extreme form leads to semelparity, or reproducing only once in their life. The simple 'minimalist' population structure of semelparous species also allows us unusual insights into many questions that are difficult to dissect in species with complex overlapping generations.