I am an astrobiologist: a geoscientist interested in the co-evolution of life and planetary environments across large spans of space and time. As a Chancellor’s Fellow (tenure-track) at the University of Edinburgh and co-director (with Charles Cockell) of the UK Centre for Astrobiology, I focus on the search for traces of ancient life in rocks from Earth that resemble those from Mars. My work has been published in about forty journal articles and book chapters, and reported by a wide range of TV, radio, online and printed media. I am a Fellow of the Royal Astronomical Society and of the Geological Society of London, a member of the Palaeontological Association and the Astrobiology Society of Britain, and an Associate Editor of the International Journal of Astrobiology, published by Cambridge University Press. I am also a STEM Ambassador.