SUMMARYHoneybees connect the sunʼs daily pattern of azimuthal movement to some aspect of the landscape around their nests. In the present study, we ask what aspect of the landscape is used in this context -the entire landscape panorama or only sectors seen along familiar flight routes. Previous studies of the solar ephemeris memory in bees have generally used bees that had experience flying a specific route, usually along a treeline, to a feeder. When such bees were moved to a differently oriented treeline on overcast days, the bees oriented their communicative dances as if they were still at the first treeline, based on a memory of the sunʼs course in relation to some aspect of the site, possibly the familiar route along the treeline or possibly the entire landscape or skyline panorama. Our results show that bees lacking specific flight-route training can nonetheless recall the sunʼs compass bearing relative to novel flight routes in their natal landscape. Specifically, we moved a hive from one landscape to a differently oriented twin landscape, and only after transplantation under overcast skies did we move a feeder away from the hive. These bees nonetheless danced accurately by memory of the sunʼs course in relation to their natal landscape. The beesʼ knowledge of the relationship between the sun and landscape, therefore, is not limited to familiar flight routes and so may encompass, at least functionally, the entire panorama. Further evidence suggests that the skyline in particular may be the beesʼ preferred reference in this context.

l) When a honey bee follows recruitment dances to locate a new food source, does she sample multiple dances representing different food sources and selectively respond to the strongest dance? (2) Several initial findings suggested that foragers might indeed compare dances. First, dance information is arrayed in the hive in a way that facilitates comparison-making: dances for different flower patches are performed close together in time and space. Second, food-source quality is coded in the dances, in terms of dance length (number of circuits per dance). Third, dances to natural food sources vary in length by more than 2 orders of magnitude, indicating that the quality of natural food sources varies greatly. Fourth, foragers seeking a new food source follow several dances before exiting the hive (though only one dance is followed closely). (3) Nevertheless, a critical test for comparison-making revealed that foragers evidently do not compare dances. A colony was given two feeders that were equidistant from the hive but different in profitability. If foragers do not compare dances, then the proportion of recruits arriving at the richer feeder should match the proportion of dance circuits for the richer feeder. This is the pattern that we found in all 11 trials of the experiment. (4) We suggest that the reason foragers do not compare dances is that a colony's foraging success is greater if its foragers distribute themselves among the various food sources being advertised in the hive than if they crowd themselves on the one, best source. (5) Food-source selection by honey bee colonies is a democratic decision-making process. This study reveals that this selection process is organized to function effectively even though each member of the democracy possesses incomplete information about the available choices.

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