ON THE ENCODING OF MOVEMENT VECTORS BY HONEYBEES - ARE DISTANCE AND DIRECTION REPRESENTED INDEPENDENTLY

Honeybees flying repeatedly over the same trajectory link it to an ass ociated visual stimulus such that on viewing the stimulus they perform a trajectory in the habitual direction. To test if trajectory length can also be linked to a visual stimulus, bees were trained to fly thro ugh a multi-comparmented maze. Bees flew through a multi-compartmented maze. In one compartment a short trajectory could be linked to a stri pe pattern oriented at 45 degrees to the horizontal. In another compar tment a longer trajectory could be linked to 135 degrees stripes. Bees made both associations: their trajectories were short when viewing 45 degrees stripes and longer when viewing 135 degrees stripes. 90 degre es stripes evoked trajectories of intermediate length. To test if dist ance and direction are linked independently to stripe orientation, a b ee's trajectory was linked to 135 degrees stripes in one compartment a nd to 45 degrees stripes in another. These trajectories were the same length but differed in their horizontal direction by 60 degrees or by 120 degrees. 90 degrees stripes evoked trajectories of intermediate di rection which were shorter than those elicited by either training patt ern. Bees were also trained to generate one long and one short traject ory with directions 120 degrees apart. The trajectories elicited by 90 degrees stripes were then biased towards the direction of the long tr aining vector. Length and direction are not treated separately. The ru les for combining trajectories resemble those of vector averaging.