Berlin, 23.2.93
.
.
        As pointed out by Peter Kevan, there is a small body of equivocal
literature on this theme. However, the question has been correctly analyzed
by experiments performed namely by A. Michelsen (Odense, Denmark), W Kirchner
(Wuerzburg, Germany) and co-workers.  The behavioural contexts of the bees'
dances and the "quacking and tooting" (commonly called "piping") of the new
queens should be first distinguished.
        In the case of the recruiting dances, the experimental evidence so
far obtained indicates that bees can actually "hear" the sounds of the
recruiter. Their hear senses are however different from our. It was first
demonstrated that dance sounds travel exclusively through the air and not
through the substrate of the comb (i.e. they are transmitted as SOUNDS and
not as VIBRATIONS)(Michelsen et al, Behavioral Ecology & Sociobiology
18:207-212, 1986).  Thereafter, it was shown that the near field of a dancer
is a zone close to the sound emitter where the air particles oscillate with
a much larger velocity than further away and where the sound pressure is
also higher (Michelsen et al, Journal of Comparative Physiology
A 161:633-643, 1987). In fact, a three-dimensional field of oscillating
airflows occurs close to the abdomen of a dancing bee.  As Towne & Kirchner
(Science 244:686-688, 1989) were successful in conditioning bees to respond
to such oscillating airflows, it was proposed that what beesactually "hear"
is the perturbation of pressure gradients and airflows in the near field of
the dancer, where most followers place indeed their antennae while following
a dance.  Moreover, it was shown, that the amplitude of the signals emitted
in the dance language is 5-10 times higher than the behavioural thresholds
(Kirchner et al, J Comp Physiol A 168:85-89,1992).  This, however, does not
exclude the possibility that the perceiving mechanism is a combination of
such air flow detection and touching of the dancer. But, using their well
known bee-robot, Michelsen et al determined that the critical parameters
are there wagging and SOUND which convey information about distance and
direction (Behav Ecol & Sociobiol 30:143-150, 1992).
.
        In the case of the queens' piping, another work of Michelsen et al
(J COMP PHYSIOL 158:605-611; 1986) showed that these "sounds" are in fact
vibrations transmitted and perceived via the substrate of the comb and a
quantitative analysis was therein performed.  In any case, the reading of
the original papers is highly recommendable.
.
Cheers,
                             Dr Martin Giurfa
 
                             Institut fuer Neurobiologie
                             Freie Universitaet Berlin
                             Konigin-Luise Str. 28-30
                             1000 BERLIN 33 - GERMANY
 
                             [log in to unmask]