Honeybee memory: Navigation by associative grouping and recall of visual stimuli

Studies of navigation in bees and ants are beginning to reveal that foragin g insects traveling repeatedly to a food source navigate by using a series of visual images of the environment acquired en route (Collett, 1996; Colle tt et al., 1993; Judd & Collett, 1998; Wehner et al., 1990, 1996). By compa ring the currently viewed scene with the appropriate stored image, the inse ct is able to ascertain whether or not it is on the correct path and make a ny necessary corrections, if a bee happens to forage at more than one site, then she needs not only to memorize a separate set of images for-each rout e that, she has learned but also to retrieve the. set of images that is app ropriate to each route. Here we examine the bee's capacity to learn and lat er retrieve from memory two different sets of visual stimuli. Bees were tra ined to fly through a compound Y-maze where they were presented alternately with two different sequences of visual stimuli on their route to a food re ward. We find that bees can indeed store two different sequences of images simultaneously. Furthermore, the trained bees-are able to classify the memo rized images into two groups, one pertaining to each three-stimulus set. Ex posure to any of the images pertaining to one set triggers recall of all of the other images associated with that set. Associative grouping and recall of visual stimuli, demonstrated here for the first time in honeybees, prov ide an effective means of retrieving the appropriate navigational informati on from memory. (C) 1999 academic Press.