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Willemet, R.

Publications and source records attributed to Willemet, R..

3 recordsLinked to original sources

Modulation of decision-making latency by innate, learned andcontextual factors in bumblebees

Foraging bee decision-making research has focused on choice determinants, and the variability and underlying causes of pre-choice latency remain understudied. Here, individual bumblebees (Bombus impatiens) were trained to associate one colored stimulus with a medium-value reward and another with a novel, higher-value reward. The experimental design consists of seven blocks, each containing four consecutive single-stimulus presentations followed by a forced binary choice. The latency to choose a stimulus and the type of choice during dual-choice trials were analysed. In dual-choice trials, bees in the yellow-high reward group showed a slower increase in high-reward selection than those in the blue-high group, suggesting persistent innate color bias. Response latencies for the low-reward stimulus systematically increased across blocks, indicating progressive devaluation. Early learning phases showed a temporary increase in response latency, extending previous findings on experience-dependent adjustments in acceptance thresholds. Latency in single-stimulus trials correlated with binary choice results, though choice proved a stronger indicator of preference than latency. Certain options elicited faster responses when presented with an alternative than when presented alone. Together, these findings support a deliberative model of bumblebee decision-making, in which pre-choice latency is modulated by innate preferences, associative learning, and immediate context.

animal behavior and cognition↗

A comparison of concept learning ability in honeybees and bumblebees using matching-to-sample tasks

Reports of honeybees demonstrating abstract concepts like sameness and difference marked a pivotal development in comparative psychology. Subsequent studies expanded the scope of concept learning in honeybee cognition, yet most evidence relies on a single method: the delayed-matching-to-sample task using a Y-maze. Whether this setup is uniquely effective or if alternative approaches could yield similar results remains unresolved. Additionally, the failure of bumblebees (Bombus spp.) to complete this task, despite honeybees demonstrating success, remains unexplained. This study compared the performance of honeybees (Apis mellifera) and bumblebees (Bombus terrestris) across matching-to-sample tasks with varying degrees of physical continuity between sample and target stimuli. The objectives were twofold: to evaluate an alternative method for assessing concept learning in both species and to investigate potential species differences in such tasks. Contrary to prior findings, neither species succeeded at the reported proficiency levels in simultaneous matching-to-sample tasks. Moreover, bumblebees outperformed honeybees in one task. These results are consistent with an explanation based on species-specific differences in visual attention mechanisms, and underscore the need for further research on concept learning in social bees.

animal behavior and cognition↗

Motivational modulation of flight speed in foraging bumblebees

The set of cognitive mechanisms employed by foraging bees is the subject of intense research due to the importance of pollination as an ecological process and as a study system in comparative psychology. Yet, our understanding of how reward valuation influences flight behaviour, and, more generally, the motivational control of behavioural vigour, remains limited. Here, the flight behaviour of individual bumblebees Bombus impatiens was recorded during a series of foraging trials in which the reward intrinsic value and predictability was manipulated. The bees could access a feeder whose sugar concentration varied from trial to trial following an increase, constant peak, and decrease pattern. Neither the feeder itself nor its position changed during the experiment. Hence, potential differences between trials could be interpreted in the context of decision-making and behavioural vigour, rather than search behaviour. The average flight speed towards the feeder increased when the sugar concentration was both high and constant, and returned to baseline as it became lower. This suggests that, as in other species including humans, the behavioural vigour of foraging bees towards a potential reward reflects its expected value. This motivational modulation of flight speed offer new ways of interpreting and studying decision-making in foraging bees.

animal behavior and cognition↗