Which element provided the first objective scientific evidence of sleep in the honey bee?
- Direct observation of motionless bees on flowers during the night.
- Electromyographic recordings showing different levels of muscle activity.
- Analysis of the decrease in thoracic temperature by infrared thermography.
- The study of queen pheromones and their calming effect on workers.
Show answer
Correct answer: 2.
Electromyographic recordings showing different levels of muscle activity.
Why?
The first objective evidence of sleep in the honey bee was provided by physiological measurements, in particular electromyographic recordings. These measurements made it possible to distinguish several levels of muscle activity, from simple rest to a state of deeper sleep.
This approach was important, because a motionless bee is not necessarily asleep. To speak of sleep, one must demonstrate an organized, recurring state associated with reduced activity and altered responses to stimulation.
What you need to understand
In the bee, sleep is not merely an absence of movement. It corresponds to a structured physiological state, with characteristic postures, reduced activity, and phases that vary according to age, role in the colony, and the moment in the day-night cycle.
Behavioural observations, such as motionless antennae or a resting posture, are useful in the field. But they become scientifically robust when linked to objective measurements of muscle or nerve activity.
Key takeaways
The correct answer is therefore electromyography: it made it possible to move from a simple observation of rest to a physiological demonstration of sleep in Apis mellifera.
For the beekeeper, this discovery is a reminder that the colony is not uniformly active at all times. Even in a highly organized society, individuals alternate between activity, rest, and sleep.