Marilyn Renfree is a reproductive and developmental biologist whose research has focussed almost entirely on marsupials (and now monotremes) because of their intrinsic interest and for the opportunities they provide as biomedical models for understanding mammalian reproduction and development. Her studies have challenged accepted dogma in several areas including mammalian development, physiological and molecular control of embryonic diapause, placentation, sexual differentiation, genomic imprinting, conservation and evolution. In particular she used the pouch young, that are essentially exteriorised fetuses, to understand how mammals develop and how the genes and hormones interact to form the new individual and how lactation is central to mammalian reproduction.

Marilyn received the Macfarlane Burnet medal of the Australian Academy of Science, the Carl G Hartman award of the US Society for Reproduction and the Marshall Medal of the UK Society of Reproduction and Fertility, the Eureka award as Outstanding Mentor of Young Researchers. She was awarded the Order of Australia (OA) in 2013. Marilyn was Secretary, Biological Sciences and Vice President of the Australian Academy of Science 2011-2015 and is a currently Laureate Professor of the University of Melbourne.