Seeing near and seeing far; behavioural evidence for dual mechanisms of pattern vision in the honeybee (Apis mellifera)

Visual perception is a primary modality for interacting with complex environments. Recent work has shown that the brain and visual system of the honeybee is able, in some cases, to learn complex spatial relationships, while in other cases, bee vision is relatively rudimentary and based upon simple elemental-type visual processing. In the present study, we test the ability of honeybees to learn 4-bar asymmetric patterns in a Y-maze with aversive-appetitive differential conditioning. In Experiment 1, a group of bees were trained at a small visual angle of 50 deg by constraining individuals to the decision chamber within the Y-maze. Bees learned this task, and were able to solve the task even in the presence of background noise. However, these bees failed to solve the task when the stimuli were presented at a novel visual angle of 100 deg. In Experiment 2, a separate group of bees were trained to sets of 4-bar asymmetric patterns that excluded retinotopic matching and, in this case, bees learned the configural rule describing stimuli at a visual angle of approximately 50 deg, and this allowed the bees to solve the task when the stimuli were presented at a novel vision angle of 100 deg. This shows that the bee brain contains multiple mechanisms for pattern recognition, and what a bee sees is very dependent upon the specific experience that it receives. These multiple mechanisms would allow bees to interact with complex environments to solve tasks like recognising landmarks at variable distances or quickly discriminating between rewarding/non-rewarding flowers at reasonable constant visual angles.