TRANSMISSION OF VIBRATION ACROSS HONEYCOMBS AND ITS DETECTION BY BEE LEG RECEPTORS

Vibration of the rims of open cells in a honeycomb, applied in the pla ne of the comb face, is transmitted across the comb. Attenuation or am plification of the vibratory signal depends on its frequency and on th e type of comb. In general, framed combs, both large and small, strong ly attenuate higher frequencies, whereas these are amplified in small open combs. The very poor transmission properties of the large framed combs used in commercial hives may explain the bees' habit of freeing an area of comb from the frame in those areas used for dancing. Extrac ellular electrical recordings from the leg of a honeybee detect large action potentials from receptors that monitor extension of the tibia o n the femur. Measurements of threshold displacement amplitudes show th ese receptors to be sensitive to low frequencies. The amplification pr operties of unframed combs extend the range of these receptor systems to include frequencies that are emitted by the bee during its dance, n amely the 15 Hz abdomen waggle and 250 Hz thorax vibration.