Michael Jennions is a professor of evolutionary biology at the Australian National University’s College of Medicine, Biology and Environment, where his research covers a range of questions in behavioural ecology. Michael’s research is primarily about the effects of sexual selection and life history trade-offs on reproductive decisions (e.g. mate choice, strategic sperm allocation, parental care, mate desertion, age at maturity and sex allocation). He is mainly interested in predictions from general theory that should be applicable across a broad spectrum of species. This has led him to collaborate with colleagues conducting empirical studies of crickets, frogs, damselflies, tropical fish, Antechinus mice, fiddler crabs and, arguably least importantly, he has conducted one study on humans. Although he is not a modeller, Michael has a long-standing interest in understanding the fundamental forces of selection that lead to the evolution of sex differences, and has collaborated with mathematically minded colleagues in this area. Finally, he is also a keen promoter of the use of meta-analysis to provide a quantitative approach to interpreting the scientific literature. He contributed several chapters to the first handbook on meta-analysis for ecologists and evolutionary biologists.