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Foraging theory assumes that animals assess value based on objective payoffs; however, animals often evaluate rewards comparatively, forming expectations based on recent experience. This form of evaluation may be particularly relevant for nectar foragers such as bumblebees, where individuals can visit thousands of flowers daily that vary in nectar quality. While many animals, including bees, demonstrate reference-based evaluation in experimental contexts, it is unclear whether this occurs in the wild. Here, we asked how daily experience with wildflower nectar influenced wild bumblebees' reward evaluation. We measured the daily nectar concentration of bee-visited wildflowers (Penstemon spp.), before presenting foragers with conspecific flowers filled with a range of artificial nectar concentrations. We recorded bees' acceptance of artificial nectar, the probability of subsequent visits to flowers on the same plant, and residence time. While bees had a minimum threshold of nectar acceptability that was unaffected by experience, when there was higher-concentration environmental nectar, they were less likely to accept lower-quality rewards on manipulated plants. Bees also visited more flowers and stayed longer on plants with higher-concentration nectar. This study shows evidence for both absolute and reference-based evaluation in wild bees and points towards differences between bees' behavior in lab- and wild-foraging contexts. [ABSTRACT FROM AUTHOR]

Social communication systems are predominantly multimodal and can combine modulatory and information-bearing signals. The honey bee waggle dance, one of the most elaborate forms of social communication in animals, activates nestmates to search for food and communicates symbolic information about the location of the food source. Previous studies on the dance behaviour in diverse honey bee species demonstrated distinct differences in the concurrence of visual, auditory, olfactory and tactile signals produced by the dancer. We studied the behaviour of dance signal receivers, the dance followers, to explore the potential significance of different signals in the communication process. In particular, we asked whether the behaviour of dance followers differs between the three major Asian honey bee species, Apis florea , Apis dorsata and Apis cerana , and whether this might correlate with the differences in the signals produced by the dancing foragers. Our comparison demonstrated that the behaviour of the dance followers is highly similar across all three species. The mean body orientation of the dance followers with respect to the waggle dancer was close to 90° throughout the run, with the majority positioning themselves lateral to the dancer. These findings suggest that the communication of spatial information might be more conserved than implied by the differences in the signals produced by the dancer. Along with studies in Apis mellifera , our results suggest that all honey bee species rely on tactile contacts between the dancer and follower to communicate spatial information. The cues and signals that differ between the species may be involved in attracting the followers towards the dancer or increasing their motivation to start foraging in the different nest environments. • Honey bee species differ in the set of signals produced in the waggle dance. • Dance followers, candidate signal recipients, were observed in three Asian species. • Follower behaviour throughout the waggle dance was highly similar across species. • Most followers oriented lateral to the dancer with a mean body angle of 90°. • The spatial information transfer mechanism is probably conserved across species. [ABSTRACT FROM AUTHOR]