In a never-before-attempted sleep experiment, Bristol Zoo has been rigged with cameras and sensors and Liz Bonnin and sleep expert Bryson Voirin stay up all night to see what the animals get up to when they think no-one is watching. From red pandas and lions to meerkats and tapirs, for the first time a whole range of animal sleep behaviours is compared and contrasted across the course of a single night.

The programme delves into the extraordinary world of animal sleep, looking at not only what science has already discovered, but the questions which remain to be answered. From dolphins, which have come up with ingenious solutions to allow them to sleep while swimming, through to ants that have developed complex behavioural patterns which ensure that the colony sleeps undisturbed, to meerkats, who keep an ear open for danger during sleep, and flamingos, which arrange themselves in order to keep a wary eye out for night-time predators. Show less