The Influence of the Quantity of Reward On the Learning Performance in Honeybees

(i) In a first series of experiments dark-adapted honeybees (Apis mellifera carnica) were trained to spectral colours (444 nm, 590 nm) in an Y-maze. The learning curves for different quantities of the reward (50 μl, 25 μl, I0 μl, 5 μl sucrose solution) were registered. The learning process is independent of the quantity of the reward. (2) In a second series of experiments freely flying bees were trained on horizontal ground-glass discs under daylight conditions. Broad-banded spectral light was projected onto the discs from below. The duration of the reward was kept constant (30 sec). By varying the influx velocity of the sucrose solution (25 μl/30 sec, 9 μl/30 sec, 2.5 μl/30 sec) the bees were offered different quantities of the reward. It can be shown that learning progress is better with the smallest quantity than with the greater ones. (3) In the discussion the learning system is described as being independent of a mechanism controlling the motivation. The experiments enable us more exactly to characterize the bee's learning system with its short-term and long-term retention.