Foraging Bumble Bees Weigh the Reliability of Personal and Social Information

Abstract

Many animals, including insects, make decisions using both personally gathered information and social information derived from the behavior of other, usually conspecific, individuals [1]. Moreover, animals adjust use of social versus personal information appropriately under a variety of experimental conditions [2-5]. An important factor in how information is used is the information's reliability, that is, how consistently the information is correlated with something of relevance in the environment [6]. The reliability of information determines which signals should be attended to during communication [6-9], which types of stimuli animals should learn about, and even whether learning should evolve [10, 11]. Here, we show that bumble bees (Bombus impatiens) account for the reliability of personally acquired information (which flower color was previously associated with reward) and social information (which flowers are chosen by other bees) in making foraging decisions; however, the two types of information are not treated equally. Bees prefer to use social information if it predicts a reward at all, but if social information becomes entirely unreliable, flower color will be used instead. This greater sensitivity to the reliability of social information, and avoidance of conspecifics in some cases, may reflect the specific ecological circumstances of bee foraging. Overall, the bees' ability to make decisions based on both personally acquired and socially derived information, and the relative reliability of both, demonstrates a new level of sophistication and flexibility in animal, particularly insect, decision-making.

Sampling and tracking a changing environment: persistence and reward in the foraging decisions of bumblebees

“…Rates of environmental change are key to theoretical treatments of when animals should learn [72], and manipulated rates of change and reliability are powerful forces influencing when learning evolves and when it does not [73 -75], and what types of information animals attend to [31]. Despite the central importance of varying rates of change on the evolution and adaptive function of cognition, change is rarely manipulated to include points between randomness and fixity.…”

“…Bumblebees are also able to use these cues flexibly, based on patterns of reliability of reward (e.g. [30,31]) and show robust reversal learning (e.g. [32,33]).…”

A social insect perspective on the evolution of social learning mechanisms

“…Accordingly, an experiment by Dunlap and colleagues initially appears to suggest that conspecifics present might be a particularly salient stimulus for bumblebees (65). In this study, subjects (B. impatiens) were trained to find sucrose rewards in floral arrays where both asocial and social cues (floral color and pinned conspecifics, respectively) provided some indication of which flowers were rewarding, before assessing which of the two cue types the bees preferentially used on a test array.…”

“…For example, above we discussed evidence that bees might acquire associations between nectar rewards and social stimuli more rapidly than associations between nectar rewards and asocial stimuli (65,68). A prepared learning hypothesis would predict that social stimuli might be particularly easy to associate with sucrose reward levels, but not with an aversive stimulus.…”

Commentary: Do Bees Play the Producer-Scrounger Game?

“…Writing in Current Biology , Dunlap et al (2016) report that foragers of the common eastern bumblebee (Bombus impatiens ) rely more on social information than on personal information if the former predicts a reward. The authors trained bumblebees to collect sucrose solution in arrays of 12 artificial flowers in which they manipulated personal information (by using yellow or orange flowers) and social information (by marking some flowers with a pinned dried conspecific).…”