Co-first authors Bernard T. Drumm (top left) and Grant W. Hennig (top right), collaborator Kenton M. Sanders (bottom left), corresponding author Salah A. Baker (bottom right), and colleagues show how slow waves in the mouse small intestine emerge from spatially distinct, asynchronous calcium transients (indicated by different colors) that sum for a prolonged elevation in internal Ca²⁺ (trace at top). Photos courtesy of the authors.