Behaviors Recorded. We identified a bee as asleep when she was in a relaxed state (i.e., body immobile, except for occasional twitches of a leg, tarsus, or extension of proboscis) and discontinuously ventilating. B.A.K. recorded sleep when individually marked bees were inside cells or when the bees were outside cells. When outside cells, bees’ antennae were immobile, exhibited minute twitches, or exhibited larger, usually swaying, motions. A discontinuously ventilating bee with immobile antennae was reported to be in a deep sleep state. Identifying discontinuous ventilation required careful examination of a bee for a minimum of 10 uninterrupted seconds, a duration estimated from an analysis distinguishing respiratory rates of heating bees versus resting bees (19). Distinguishing the antennal state required an average minimum of 3–5 s. If a bee was obscured from view, then her behavioral state was not recorded. A bee sleeping inside a cell could not be distinguished as exhibiting deep sleep, because her antennae were hidden from view. For more information on identification of sleep in honey bees, see Klein et al. (21).