Fig. 4. Experiment 2. Scent-triggered navigation of groups of bees trained simultaneously to a rose-scented and a lemon-scented feeder placed at two different locations. The figure shows means ± S.E. of visits by marked bees to empty, unscented test feeders (white, rose feeder; grey, lemon feeder) during an 8 min no-scent interval (air, unfilled bars) and an 8 min scent interval (hatched bars), when either rose scent (above) or lemon scent (below) was blown into the hive. N=5 tests for each scent and each no-scent interval. Different letters above bars denote significant difference at a level of at least P<0.05 (Friedman ANOVA and Wilcoxon Matched-Pairs test).