Percentage of bees showing proboscis extension response (mean+SE) of pollen (P, solid) and nectar (N, empty) foragers of <i>Apis mellifera</i> (triangles) and <i>A. cerana</i> (circles) in their own colonies, across different sucrose concentrations (plotted as log scale but with actual concentrations).

<p>A: unfed foragers tested directly, Data based on 10 colonies per species (N = 600 bees). B: foragers tested 30 min after being fed 5μl 30% sucrose solution. Data based on 5 colonies per species (N = 300 bees).