Search Behavior of Individual Foragers Involves Neurotransmitter Systems Characteristic for Social Scouting

Area of Science:

• Animal Behavior
• Neuroethology
• Insect Ecology

Background:

• Honey bees display distinct social and solitary behaviors during foraging.
• Specialized foragers, or scouts, recruit naive foragers (recruits) to food sources.
• Recruits typically do not search independently but will search if a food source is removed.

Purpose of the Study:

• To provide a detailed description of solitary search behavior in honey bee recruits.
• To investigate individual variations in this solitary search behavior.
• To explore the neurochemical underpinnings of solitary search initiation and performance.

Main Methods:

• Detailed behavioral observations of individual honey bee foragers.
• Experimental manipulation of food source availability.
• Mass spectrometric analysis of neurochemicals in the optic lobes and central brain.

Main Results:

• Solitary search behavior in recruits was described, highlighting individual differences.
• Initiation and performance of solitary search were associated with changes in specific neurotransmitters (glutamate, GABA, histamine, aspartate) and the catecholaminergic system.
• Neurochemical findings align with previous studies showing differences in glutamate and GABA receptor expression between scouts and recruits.

Conclusions:

• Behavioral specialization in honey bees, particularly the transition to solitary search, is linked to neurochemical adjustments.
• Modulatory systems governing solitary behavior appear to be modified to enhance specific behaviors.
• These findings support the hypothesis that behavioral specialization is based on the fine-tuning of neural systems for solitary actions.