I have been reading a review copy of a book recently
translated into English named "The Buzz About Bees"
by Jurgen Tautz of the University of Würzburg, Germany.
It comes close to Tom Seeley's "The Wisdom Of The Hive"
in terms of overall quality, but it lacks the meticulous
citations Tom put in his book, so one is left to bang
away on citation databases in hope of finding primary
sources. Annoying.
Anyway, the book addresses the "dialects" issue very
succinctly, so I will quote from the uncorrected proof
of the book:
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"The duration of the waggle phase exhibits only minimal
differences when the dances of different bee races are
compared for one and the same flight path. A comparison
of the dances of bees of the same race for the same
distance, but over different terrain, reveals the
landscape-dependent differences to be significantly
greater than the race-dependent variation."
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Below is a longer set of snippets, which lead up to
and explain the quote above.
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"Some unambiguous correlations can be noted: with basically
the same frequency of waggle movement, the longer the waggle
phase of the dance lasts, the further the bee has to fly to
the source. However, the duration of the waggle phase
increases proportionally to the distance only over the
first few hundred meters; thereafter, it increases more
gradually, and the distance information to remote goals is
consequently less precise.
An additional difficulty arises from the bees’ use of a visual
odometer to determine the light distance that is communicated
in the dance. he data delivered by this odometer are relative
to the structural nature of the surroundings through which the
bee lies.
When lying through a structured environment, the images of
objects move across the facets on the surface of the compound
eye of the bee. his result in an 'optical flow' in the visual
field of the bee, which helps the bee determine her flight speed.
Honeybees that fly to the feeding site through a narrow tunnel
with patterned walls experience an artificially increased
optical low along a short distance of the path they have to
fly (Fig. 4.22). These bees have been deceived, and translate
the increased optical flow into a longer distance, resulting
in a correspondingly long waggle phase. This simple deception
in terms of estimated distance opens a window into the
subjective experience of bees, in which measurements of the
length of the waggle phase are an indication of how far the
bees believe they have flown.
The application of the 'deception tunnel' confirmed some old
ideas, disproved others, clarified disputed points, and
provided the following new insights:
1) Refuted the opinion that bees use energy consumption
as a measure of flight distance.
2) Confirmed the use of the visual odometer.
3) Confirmed the old suspicion that distance measurements
are made on the outward, not on the return Flight.
4) Explained and settled the decade-long controversy about
the waggle dance, in which it was disputed whether or not
the recruited bees followed the information coded in the
waggle dance. The tunnel enabled one to produce bees that
made errors, visiting feeding sites 6 m from the hive,
but in their dance signaling a distance 30 times longer.
Searching recruits were not found lying around the
indicated food source, but in an area much further away
where there was nothing of interest. Information from the
dance is used.
5) Led to the realization (with the help of colored patterns
in the tunnel) that, of the three color-sensitive visual
receptor cells in the complex eye of the bee—which
individually react best to either ultraviolet, blue, or
green—only the green receptor is used in measuring distance.
The simple manipulation of the bee dance by means of tunnel
flights demonstrated that the distances that the visual odometer
was indicating to the bees were influenced by the structure of the
landscape along the light path. In a test of this idea, a light path
that passed through a landscape of even appearance was found to
result in a dance with a short waggle phase, whereas a light path
of the same length through a complex, structured landscape led
to a long waggle phase. Should bees fly to feeding sites that are
the same distance from the hive but lie in different directions,
the waggle phases of their dances, and so the indication of the
distance, can differ by a factor of two. A waggle phase of 500 ms
(millisecond) could, in the case of a light to the south, mean a
distance of 250 m, and for a light to the west from the same hive,
500 m (Fig. 4.23).
From this, we can draw two conclusions:
1) The odometer of bees does not deliver absolute distance
information, and is useful only when the followers leave the
hive in exactly the same direction (and altitude) as the dancer.
2) There needs to be a reevaluation of the idea that in the
translation of light paths of the same length, bees of different
races differ in the duration of the waggle phase, because their
dance languages have different 'dialects'.
The duration of the waggle phase exhibits only minimal
diferences when the dances of different bee races are compared for
one and the same flight path. A comparison of the dances of bees
of the same race for the same distance, but over different terrain,
reveals the landscape-dependent differences to be significantly
greater than the race-dependent variation. In assessing the
coding of the light path length in the bee dance of different
races in different areas, one is therefore comparing the visual
properties of the landscape, rather than the properties of
bee races."
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