Bumblebees Learn a Relational Rule but Switch to a Win-Stay/Lose-Switch Heuristic After Extensive Training.

Hadi Maboudi,Lars Chittka,Cwyn Solvi

doi:10.3389/fnbeh.2020.00137

Abstract

Mapping animal performance in a behavioral task to underlying cognitive mechanisms and strategies is rarely straightforward, since a task may be solvable in more than one manner. Here, we show that bumblebees perform well on a concept-based visual discrimination task but spontaneously switch from a concept-based solution to a simpler heuristic with extended training, all while continually increasing performance. Bumblebees were trained in an arena to find rewards on displays with shapes of different sizes where they could not use low-level visual cues. One group of bees was rewarded at displays with larger shapes and another group at displays with smaller shapes. Analysis of total choices shows bees increased their performance over 30 bouts to above chance. However, analyses of first and sequential choices suggest that after approximately 20 bouts, bumblebees changed to a win-stay/lose-switch strategy. Comparing bees’ behavior to a probabilistic model based on a win-stay/lose-switch strategy further supports the idea that bees changed strategies with extensive training. Analyses of unrewarded tests indicate that bumblebees learned and retained the concept of relative size even after they had already switched to a win-stay, lost-shift strategy. We propose that the reason for this strategy switching may be due to cognitive flexibility and efficiency.

Highlights

Cognitive flexibility reflects an individual’s ability to adaptively alter their behavioral strategy following a changing environment (Wasserman and Zentall, 2006)
A multivariate statistical model, generalized linear mixed model (GLMM), applied to the performance of bees demonstrates a significant increase in the proportion of correct choices made over the 180 choices of the training phase (Figure 2A, p = 0.018) irrespective of the shape, color or position of patterns within the stimuli
We demonstrate and corroborate previous findings (AvarguèsWeber et al, 2014; Howard et al, 2017) that bees can learn a relative size rule, but in our study, they opted to use a simpler strategy after extensive training

Summary

Introduction

Cognitive flexibility reflects an individual’s ability to adaptively alter their behavioral strategy following a changing environment (Wasserman and Zentall, 2006). With an increased number of training trials with a single pair of patterns, individual honeybees have been shown to have a greater generalized response to novel stimuli, i.e., the representation necessary to discriminate subsequent visual patterns changes with extended training (Stach and Giurfa, 2005). All of these findings highlight the need for considering alternative strategies used by animals in cognitive tasks. Different individuals may use different solutions that are equal in complexity, depending on their particular path to figuring out a solution

Methods

Results

Conclusion