DYER, Fred C.: Vector Navigation in Insects

Honey bees and other insects that forage from a central place face a formidable navigational problem, which is to find their way repeatedly between their nest and feeding places in the environment. A key component of the insects’ solution to this problem is an ability to determine the direction and distance of travel via path integration, or dead reckoning. To carry out path integration requires an accurate compass and odomoter. In honey bees we know that the primary compass reference is the sun, while odometry is mediated by optic flow. This talk will review recent research that provides new insights into the nature of these navigational systems in insects. Specifically, the talk will focus on the following issues: (1) how insects learn to compensate for the movement of the sun over the day; (2) where the visual inputs into the insect sun-compass originate at the periphery; (3) how directional and distance information are combined to encode the navigational vector corresponding to a particular feeding place; and (4) the role of motivational cues mediating the use of vector information corresponding to a particular foraging route. Most research to be described has relied upon behavioral approaches. However, as we shall see, these experiments have helped to clarify the possible neural mechanisms underlying vector navigation in insects, and hence will be useful in paving the way for anatomical, physiological, and pharmacological investigations.