Carl Zimmer is an award-winning science writer and New York Times columnist. A three-time winner of the American Association for the Advancement of Science’s journalism award, in 2021 Carl was a member of the team at The New York Times which won The Pulitzer Prize in Public Service for their coverage of the Covid-19 pandemic. In this in-depth interview, Carl discusses the topic of his latest book – ‘Life’s Edge: The Search for What It Means to Be Alive’ – shedding light on why it is “very difficult and may be impossible” to know precisely what life and death actually are; shares some of the problems that are caused by humans “wrongly making themselves the centre of any definition of life”, instead of realising that “the vast majority of life is not like us”; and reflects on just how much the pandemic dominated his work for two years, and how people trusting the accuracy of Covid-19 coverage is quite literally a matter of life and death.