Lifetime performance in foraging honeybees: behaviour and physiology

Area of Science:

• Zoology
• Insect Physiology
• Animal Behavior

Background:

• Honeybee (Apis mellifera) foraging efficiency increases with experience.
• This improvement may be due to learning or physiological adaptations in flight ability.
• Understanding physiological contributions is crucial for explaining enhanced foraging performance.

Purpose of the Study:

• To investigate the role of physiological changes in the flight muscles of honeybees as they gain foraging experience.
• To assess how flight muscle biochemistry and enzyme activity change throughout an adult honeybee's foraging lifespan.

Main Methods:

• Proteomic analysis (two-dimensional gel electrophoresis) of honeybee thorax muscle.
• Measurement of enzyme activities (V(max)) related to aerobic metabolism in flight muscles.
• Comparison of muscle components across different life stages: hive bees, young, mature, and old foragers.

Main Results:

• Proteomic analysis revealed increased levels of proteins like troponin T 10a, aldolase, and superoxide dismutase in mature foragers compared to hive bees.
• Enzyme activities of phosphofructokinase, hexokinase, pyruvate kinase, and cytochrome c oxidase did not significantly change with foraging experience.
• Citrate synthase activity, an indicator of aerobic capacity, increased with foraging experience.

Conclusions:

• Honeybee flight muscles exhibit plasticity, with both structural (protein levels) and metabolic (citrate synthase activity) components changing with foraging experience.
• These physiological adaptations likely contribute to the observed increase in foraging performance as bees gain experience.