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From:
Adrian Wenner <[log in to unmask]>
Reply To:
Informed Discussion of Beekeeping Issues and Bee Biology <[log in to unmask]>
Date:
Sun, 13 Feb 2000 14:12:40 -0700
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Denmark contributor Lars Hansen's Question #3 (18 January):

   Speaking of natural conditions: Could it be, that the area where some
have experimented favoured a conclusion that odor is less important?  And
did the areas where others have experimented favor the opposite conclusion?
As a European, I'm not familiar with American geography in detail, but I
guess that a plains area and a small valley would emphasize different
aspects?

**********

   To alter the thrust of his question slightly, control against odor
artifacts in these types of experiments is more difficult to accomplish in
some areas than in others.

   For instance, in most of the eastern United States and in central Europe
(correct me if I am wrong on that), summer storms pass through with some
degree of frequency.  Winds tend to be in one direction during an
approaching storm and in a quite different direction during a clearing
condition.

   Bees from a colony in those areas can thus collectively forage rather
well in more than one direction.  Foragers learn landmarks and can remain
faithful to a good food source for days or weeks on end.  As winds shift,
other foragers can forage in other directions simultaneously.

   Consider the results of an 8-day study conducted by Visscher and Seeley,
published in 1982 (partly summarized in Fig 7.3 of Seeley's 1985 HONEYBEE
ECOLOGY book).  They observed dance maneuvers in an observation hive and
noticed that foraging occurred primarily in one direction (SSW).  A
rainstorm moved in, at which time bees foraged close to the hive (as
written about by Virgil).  After the storm passed, however, most foraging
that they tallied occurred in a NE direction.

   Visscher and Seeley did not publish information on wind direction, but
their results can mesh with an odor-search hypothesis; foraging occurs
primarily in one direction from the hive.  Rain would wash nectar out of
some types of flowers --- the foragers to that source would have to wait
until those blossoms again yielded.  The APPARENT switch to another
direction in their study could be because other foragers visit another type
of flower that still had nectar and would still provide dance maneuvers for
those localities in the hive.

   The Visscher and Seeley interpretation:  Some foragers had found a
"better" source, and their dances had converted the foraging population to
the new direction.

   I know, though, that foragers remain faithful to given sources for days
or weeks.

*********

   In the Santa Barbara area we have a distinct advantage while conducting
these types of experiments.  Weather fronts move far to the north of us
during the summer, and we normally have no rain between early April and
November.  Each day during the summer usually begins with light fog that
dissipates by midday.  The slight breeze from the SE in the morning
gradually switches to a stronger breeze from the SW in the afternoon each
day.

   The above set of circumstances enabled us to conduct our [1969]
"crucial" experiment for a 24-day period, with nearly identical weather
conditions for 3 hours each morning.  The crucial experiment design we
employed has two competing hypotheses (odor-search and language) pitted
against one another.  That is, a set of results will support one hypothesis
and negate the other, or vice versa --- ambiguity cannot exist.  The
results were published as follows (also summarized in Chapter 10 of our
book, ANATOMY OF A CONTROVERSY):

1969  Wenner, A.M., P.H. Wells and D.L. Johnson.  Honey bee recruitment to
food sources:  Olfaction or language?  SCIENCE.  164:84-86.

   A summary of some results of that study follows:

1)  We collected a total of more than 2000 recruited bees during the
experiment.

2)  At stations where odor was present and routinely visited by a total of
20 different foragers, we got about 26 new recruits per hour.

3)  At those same stations, under the same conditions but without odor, we
obtained only 2 recruits per hour.  (It is difficult to get rid of all
traces of odor.)

4)  During the same period (as in 3), as regular foragers visited feeding
stations without odor, we had a third station with a feeder and the ODOR OF
THE DAY BEFORE.  That station had 19 arrivals per hour, with NO forager
visitation and NO DANCES for that site in the hive.  (Note the contrast:
19 per hour to odor but only 2 per hour where dances in the hive had
presumably directed them.)

   I will gladly mail a copy of that article to anyone who wishes (furnish
a mailing address, please).

   An academic question:  "Will you find the results of this experiment
mentioned in writings by language advocates?"

*********

   In reply to Lars Hansen's questions, then, I don't believe that
researchers in the eastern U.S. or in Europe can satisfactorily conduct
such an experiment, due to rather frequent changes in the weather and due
to the fact that locality odors (distinctive smells in different places)
become a much greater problem where one has rain.

                                                             Adrian


Adrian M. Wenner                    (805) 963-8508 (home phone)
967 Garcia Road                     (805) 893-8062  (UCSB FAX)
Santa Barbara, CA  93106

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*
*  "When we meet a fact which contradicts a prevailing theory,
*     we must accept that fact and abandon the theory, even when
*     the theory is supported by great names and generally
*     accepted."
*
*                                       Claude Bernard --- 1865
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