Quantitative analysis of risk sensitivity in honeybees (Apis mellifera) with variability in concentration and amount of reward.

Free-flying honeybees (Apis mellifera) were trained in a series of experiments designed to look for evidence of risk sensitivity in foraging for sucrose solution. The suitability of the choice method used was established in 3 preliminary experiments with differences in concentration, amount, and probability of reward. Of 5 subsequent experiments in which 2 alternatives provided the same mean concentration of sucrose solution with different variance, 3 showed risk indifference, and 2 showed risk aversion (preference for consistent reward). Of 2 final experiments in which the alternatives provided the same mean amount of sucrose solution with different variance, both showed risk aversion. Performance could be simulated quantitatively with a simple choice model developed by P. A. Couvillon and M. E. Bitterman (1991) to account for the results of a wide range of previous experiments on discriminative learning in honeybees.