The papers in this special edition arose from a 2017 workshop at the Australian National University with a broad theme: the evolution of religion across the disciplines. It was organized by the ANU's School of Philosophy and Centre for Philosophy of the Sciences, a center whose title contains a deliberate pluralization. This field has always been diverse. Foundational figures in anthropology, psychology, and sociology, such as Edward Tylor, William James, and Emile Durkheim took the study of religion as fuel for immensely productive but only partially-overlapping lineages of enquiry, with religions variously seen as primarily social institutions; as patterns in individuals' activities and social interactions; or aspects of individual cognition and motivation. Additionally, the differences between distinct religions are considerable; so is there a unitary phenomenon to explain? Dan Sperber thinks not, see his response to Sterelny (2018a). Little wonder that the differing scientific approaches to religion are so divergent, and that is before considering how religion looks through the lens of economics, archaeology, philosophy, etc. This heterogeneity of topics, approaches and examples made it a challenge to assemble a workshop (and its products) that was both genuinely interdisciplinary but with some productive cross-fertilization. We think there was cross-fertilization, and we hope this special issue shows that. What follows is a road map of the special issue, with a glance at the main intent of each paper, identifying some common themes of cost, honesty, normativity, and the nature and role of religious belief.The workshop itself was a two-day meeting with eight long presentation and discussion sessions covering overlapping topics from the social psychology of religiosity (