QUOTE : The apprentice is required to master many techniques before receiving safari guide certification. Among the most difficult and essential of these skills is the ancient practice of unihemispheric slow-wave sleeping. The ability to sleep with half of the brain while the other remains completely alert, alternating between hemispheres, allows the guide to remain conscious twenty-four hours a day. This unconventional method has been observed in a number of terrestrial, aquatic and avian species, particularly those that dwell in areas of high predation. It is strongly recommended that safari guides avoid full REM sleep while guiding safaris. Though, when charged with the care of the most demanding and pampered of clients, a traditional fifteen minute nap is occasionally permitted.