S Stach | PubMed Health

PubMed2003

The automatic pilot of honeybees.

Using scanning harmonic radar, we make visible for the first time the complete trajectories of "goal-vector" flights in honeybees. We demonstrate that bees captured at an established feeding station, and released elsewhere, nevertheless embark on the previously learned vector flight that would have taken them directly home from the station, had they not been artificially displaced. Almost all of the bees maintained accurate compensation for lateral wind drift, and many completed the full length of the vector flight before starting to search for their hive. Our results showed that bees tend to disregard landscape cues during these vector flights, at least initially, and rely on the "optic flow" of the ground beneath them, and their sun compass, to judge both direction and distance.

Animals↗

PubMed1999

Pattern learning by honeybees: conditioning procedure and recognition strategy.

In recognizing a pattern, honeybees Apis mellifera, may focus either on its ventral frontal part, or on the whole frontal image. We asked whether the conditioning procedure used to train the bees to a pattern determines the recognition strategy employed. Bees were trained with the same patterns presented vertically on the back walls of a Y maze. Conditioning was either absolute, that is, bees should learn to choose a rewarded pattern when there is no alternative, or differential, that is, bees should learn to choose a rewarded pattern that is paired with a different, nonrewarded one. Bees used different pattern recognition strategies depending on the conditioning procedure: absolute conditioning restricted recognition to the lower half whilst differential conditioning extended it to the whole pattern. Bees trained with absolute conditioning saw and learned the features of the upper part of the trained patterns, but assigned more weight to the lower part. Bees trained with differential conditioning learned not only the features of the reinforced stimulus in an excitatory way, but also those of the nonreinforced one in an inhibitory way. Thus, conditioning tasks that involve not only excitatory acquisition of the conditioned stimulus per se, but also discrimination of nonreinforced stimuli, result in an increase in the visual field assigned to the recognition task. Conditioning tasks that involve only excitatory acquisition of the rewarded stimulus result in a higher weighting of the lower pattern half and thus in a more reduced field assigned to the recognition task. This difference may reflect that existing between a conditioned and an incidental behavioural modification. Copyright 1999 The Association for the Study of Animal Behaviour.

Journal Article↗