For most people, bedtime is a routine matter of turning off the lights and hoping for eight hours of rest. For David R Samson, an associate professor of evolutionary anthropology, it often means venturing deep into the wild or far back in evolutionary time. Whether sleeping high in the forest canopy to study chimpanzees or joining the Hadza tribe in remote Tanzania, Samson’s Indiana Jones-style fieldwork exposes the ancient roots of human slumber. As director of the Sleep and Human Evolution Lab...