Temporal consistency of judgement biases in bumblebees

Area of Science:

• Animal Behavior
• Cognitive Ecology
• Invertebrate Cognition

Background:

• Judgement bias tasks are used to assess animal affective states.
• Distinguishing between transient affective states and stable behavioral traits in these tasks is challenging.

Purpose of the Study:

• To investigate the repeatability of responses in bumblebees using an active choice judgement bias task.
• To determine if judgement biases in bumblebees reflect stable traits or transient states.

Main Methods:

• Bumblebees (Bombus terrestris) participated in three repeated sessions of an active choice task.
• Bees were trained to associate colors with high or low rewards.
• Ambiguous colors were presented during testing to assess choice bias and response latency.

Main Results:

• Bees showed a bias towards the high-reward chamber and faster responses to cues closer to the positive color.
• Response latency exhibited moderate and significant repeatability across sessions, indicating a trait-like component.
• Chamber choice repeatability was negligible, suggesting state-dependency and influence of situational factors.

Conclusions:

• Judgement biases in bumblebees, particularly in active choice tasks, are influenced by transient affective states and external factors.
• Response latency may serve as a more reliable indicator of stable behavioral traits than choice behavior alone.
• Active choice tasks offer a valuable tool for disentangling stable traits from affective states in invertebrates.