Fig. 1.

Average counts of color-marked workers in small nuclear hives when a queen is present (blue triangles) and in the absence of the queen (red stars) are shown with corresponding average mortality rates (inserts). The first replicate (a) showed an initially rapid decline of workers in the queenless hives, indicated by a high initial mortality rate (insert: red, long-dashed line). This initial effect is also apparent to a lesser degree in the second replicate (b). However, the initial declines do not present an age-related mortality but rather mis-orientation and failure to remain in the experimental hives due to the lack of attractive queen pheromones. At the relevant later ages, mortality in the queenright hives (insert: blue, short-dashed line) generally exceeds the mortality of workers under queenless conditions