Fig. 1. The effect of varying tunnel length and orientation on the mean waggle duration of bees returning to the hive after feeding inside the tunnel. Values are means ± s.d. for each experimental condition. The walls and floor of the tunnel were lined with checkerboard patterns in all cases but one, where axial stripes (Ax) were used instead. The mean waggle duration varies with the length of the tunnel but not with its three-dimensional configuration. Abbreviations: 4m, 4 m tunnel; 6m, 6 m tunnel; h, horizontal tunnel; o, oblique tunnel, 48° incline; v, vertical tunnel; L, L-shaped tunnel, with a 2 m vertical section followed by a horizontal section.