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ADRIAN M. WENNER
PATRICK H. WELLS
Library of Congress Cataloging-in-Publication Data
Wenner, Adrian M.
Anatomy of a controversy:
the question of a 'language" among bees
Adrian M. Wenner, Patrick H. Wells.
p. cm.
Includes bibliographical references.
ISBN 0-231-06552-3
1. Honeybee-Behavior.
2. Animal communication.
I. Wells, Pairick H.
II. Title.
QL568.A6W46 1990
595.79'90459-dc2O
90-30539
CIP
Columbia University Press New York
CONTENTS
Preface
Acknowledgments
1. Science, Controversy, and the Question of a Honey Bee Language
2. Philosophers and Paradigms
3. Relativism and Strong Inference
4. Two Hundred Years of Uncertainty
5. The Odor-Search Paradigm: History and Revision
6. The Dance Language Paradigm: Evolution and Acceptance
7. A Parade of Anomalies: Learning
8. A Parade of Anomalies: Odor
9. TransItion in Approaches: Testing the Dance Language Hypothesis
10. Multiple Inference and "Crucial" Experiments
11. The Social Network
12. Reaffirming the Dance Language Hypothesis: Initial Attempts
13. The Realism School and Interpretation of Behavior
14. The Dance Language Controversy: Conflicts Between Paradigms
Excursuses
References Cited
Index
Excursis
SI: The Salk Institute
Stimulus
"We have to understand
first how many elements can be brought to bear on a controversy;
once this is understood, the other problems will be easier to
solve.'
-Bruno Latour 1987:62
Interviewing successful scientists is a technique often used
by sociologists and philosophers of science when they wish to
ascertain the reasons for scientific achievement. On the other
hand, many mistakes are made in projects that are begun with
the best of intentions; projects started may fail early in the
planning stages due to faulty assumptions. Such attempts are
rarely the subjects of discussion. One can be certain in any
event that the interview technique is unlikely to reveal many
truly embarrassing episodes.
What propels a research project forward? Sometimes the desire
to know suffices. At other times adversity plays an important
role; the desire to prove oneself correct and others wrong can
be quite an incentive. One might even say that controversy fuels
important scientific progress. However, a great many such incidents
in science go unreported and thereby completely escape the attention
of sociologists, psychologists, historians, and philosophers
of science.
Under the current anonymous peer review grant system, unfortunately,
adversity can lead to the early termination of a project. Another
social factor prevails, despite claims to the contrary; the scientific
community is uncomfortable with controversy, unless the issue
is rather unimportant (see chapter 14). All of this means that
discussion of only a very small portion of conflict resolution
actually reaches print.
Our volume would not be complete without a recounting of one
such experience Wenner had at the Salk Institute during the mid-1960s.
It was an incident that led to the first real test of the dance
language hypothesis.
The first question one might ask is, "Why should a bee researcher
be involved with the Salk Institute?" The occasion appears
to have been the intended launching of a major research project
spawned by Jacob Bronowski. He had apparently convinced the Salk
Institute leadership that they could unravel brain function by
conducting research on the "dance language" of bees.
A "kickoff" seminar was to be given by Harald Esch
of Notre Dame University.
The following account of that experience is necessarily written
in the first person singular by Wenner. The accuracy of the account
was verified by one of the participants, the renowned honey bee
geneticist Harry Laidlaw of the University of California at Davis.
When he read the account, he remained silent for a long while
and then commented, "Yes, that's how it was." After
a brief pause he added, "But are you sure you should publish
it?" Wenner's account follows.
THE HARALD ESCH SEMINAR
Jacob Bronowski telephoned in 1965 and invited me to serve as
a "discussant" immediately following a talk to be given
at the Salk Institute by Harald Esch of Notre Dame University.
Esch and I, who had never met before then, had independently
recorded sounds made by forager bees (see chapter 6) during their
dance maneuver within the hive. Both of us had also appreciated
the potential significance of those sounds in terms of the purported
"dance language" (see Esch 1961; Wenner 1959, 1962,
1964). We both reasoned at that time that bees maybe used sound
rather than the dance configuration during communication.
The invitation was quite puzzling for at least two reasons. First
of all, the Salk Institute is not known for its interest in natural
history studies. Secondly, the formal use of a "discussant"
after scientific seminars is a rather rare event. In that arrangement,
one person or a group of people give presentations. Then a designated
"discussant" provides pro and/or con arguments about
the material presented. This procedure seems to be a means by
which some notion or other can be "legitimized" in
the minds of those present.
Since this invitation came when all of us still worked within
the dance language paradigm, it would appear that the occasion
was expected to proceed smoothly. Esch would give his presentation,
and I would discuss the material and give a "stamp of approval"
on the idea that the 'dance language" hypothesis of bees
was valid.
By the time that Bronowski extended his invitation, however,
my colleagues and I had already succeeded in conditioning honey
bees to respond as if to a language upon the presentation of
a stimulus (see chapter 7). We had also already recognized the
implications of that conditioned-response behavior during the
rerecruitment of foragers in nature. That is, we knew that experienced
bees did not need to "use" information contained
in the dance (see Wenner 1974) as they once again traveled to
food sources that they had visited earlier.
Those conditioning experiments had thus revealed to us what von
Frisch (1950) and Ribbands (1954) had meant when they reported
that experienced bees could be rerecruited to food sources "without
the need for a dance." As indicated in chapter 7, at any
one time virtually all foraging bees are experienced. That means
that foragers would rarely be recruited to food sources by means
of the presumed "dance language."
At the time of the invitation from the Salk Institute, we had
already perceived that the "dance language" of bees,
if it existed (and we were no longer certain of that), would
be useful primarily for the recruitment of naive bees. Once those
naive recruits learned the location of nectar, however, they
could very well spend much of their remaining life visiting that
one source. Rerecruitment each day could be by means of conditioned-response
behavior.
While inviting me, Bronowski asked if I knew of a good bee geneticist,
which I did. Harry Laidlaw of the University of California at
Davis had had a long-term association with my beekeeper relatives
in Northern California and was perhaps the world's leading bee
geneticist at the time. Subsequently he was also invited to the
Salk Institute at the time of Esch's seminar.
Another factor entered in. When Bronowski invited me to be a
discussant for Esch's talk at the Salk Institute, we had already
completed and submitted two manuscripts to journals. Those papers
described the results of our experiments on simple conditioning
(Wenner and Johnson 1966) and communication by means of conditioned
response (Johnson and Wenner 1966). I therefore felt it my professional
responsibility to provide the results of these experiments to
both Esch and Bronowski before the forthcoming event, even though
I was unaware at the time of the reason for Esch's forthcoming
talk at the Salk Institute (see below). Bronowski acknowledged
receipt of the manuscript but encouraged me to come despite that
new development and despite any possible implications of those
results to the question of honey bee recruitment.
PRECIPITATION OF A CRISIS
The seminar setting at the Salk Institute totally surprised me.
I was expecting a small, relatively informal seminar, as is customary
at academic institutions. Instead, perhaps three hundred people
were in attendance, as well as television crews and reporters
for major news outlets. This was obviously not a routine academic
seminar, but no one had informed me of that fact.
Just before Esch began his talk, Bronowski requested that I not
mention any of our latest experimental results on honey bee learning
(the content of the manuscripts sent earlier) during my "discussion"
of Esch's seminar at its conclusion. He said, "That matter
can be handled tonight at the dinner."
Bronowski's request caught me unawares, because scientists pride
themselves on being open and receptive to new ideas and information.
Why then, I wondered, the sudden insistence on even a temporary
suppression of new results? Claude Bernard had criticized such
action, as follows: "True science suppresses nothing, but
goes on searching, and is undisturbed in looking straight at
things that it does not yet understand" ([1865] 1957:223).
Esch's talk was, to me, a quite elementary treatment of the presumed
evolution of the honey bee "dance language." He outlined
a scheme whereby the intricate "recruitment dance"
pattern of European bees (which contains information on the distance
and direction of food sources; see chapter 6) could have evolved
from the behavioral patterns found in related genera of bees
living in tropical and subtropical countries.
Esch failed to mention an important point; one could argue equally
convincingly that evolution could have proceeded the other way.
For example, stingless bees may be considered more "advanced"
than European bees, because they have secondarily lost
their sting. That is because the sting is a modified ovipositor
found in most bees, wasps, and ants.
Taxonomists now recognize that honey bees are not as closely
related to stingless bees (Kimsey 1984) as once thought (Michener
1974). Rather, stingless bees are in another (earlier) branch
of the family Apidae. Honey bees are thus more closely related
to the bumble bees and euglossine bees, which have no dances,
than they are to the stingless bees.
During Esch's presentation my thoughts were in turmoil. How could
Bronowski, a renowned scholar, mathematician, and philosopher,
insist on suppressing results, even if only temporarily? Furthermore,
how could I "discuss" Esch's exposition on the "evolution
of bee language" in front of three hundred people and reporters,
when our experimental results on learning had the potential of
relegating the entire "dance language" hypothesis into,
at most, a minor facet of honey bee recruitment?
I found myself in a position that was probably incomprehensible
to
the rest of the audience. I had already undergone a "paradigm
shift" in the Kuhnian sense and had resolved the "crisis"
state in my own mind, it had been evident to my colleagues and
to me that our experimental results on conditioned responses
had matched almost perfectly the earlier experimental results
described by von Frisch (1950) as evidence of "dance language"
use.
However, von Frisch had not addressed the importance of learning
during recruitment and had insisted that the rerecruitment of
experienced bees (which we now recognized as conditioned responses)
was "proof" that bees had a "language." By
contrast, we now realized that two interpretations existed that
could both fit that same set of experimental results.
The circumstance we were in was remarkably similar to that encountered
by Thomas Kuhn when he was able to perceive that scientists behaved
differently from the pattern perceived or advocated by Karl Popper
(the "wearing of a new set of spectacles"). How could
I then discuss the "evolution of bee language" in front
of the audience at the Salk Institute when the very foundation
of that hypothesis had been shaken to its roots in our minds?
We had undergone a "gestalt switch" and viewed the
same results from the vantage point of a new paradigm (see chapter
5 and excursus OS). Once that happens, there is no going back.
Eventually there came the moment of truth. Esch ended his seminar
to resounding applause. Then it was my turn to say something
to that same audience, an audience that was content with the
dance language hypothesis and that was totally unaware of our
experimental results and the implications of those results for
that hypothesis.
A LACK OF ADEQUATE CONTROLS
As I walked to the front of the room, my dilemma became resolved.
For the very first time, I realized that von Frisch's original
experiments had lacked adequate controls against forager flight
paths and extraneous odor cues. I had "created the image"
at that instant, on the way to the front of the room, in the
sense meant by Atkinson (1985) and Wenner (1989) (see also figure
3.1).
The idea that von Frisch's original experiments lacked adequate
controls was conceded later even by proponents of the dance language
hypothesis (e.g., Seymour Benzer in 1966; in a personal communication;
Gould 1976). As Gould wrote at that time: "Throughout the
dance-language controversy, Wenner has made perceptive and valuable
contributions. Von Frisch's controls do not exclude the possibility
of olfactory recruitment alone" (1976:241).
However, that open and tolerant attitude did not prevail at the
Salk Institute that day. Nevertheless, I had to address the issue
as I saw it with my "new spectacles," as Kuhn phrased
it. If a "dance language" had never really been established
as 'fact," there was little need to address, at that time,
the points made by Esch in his seminar. Any discussion of evolution
of "the dance language" (in the teleological sense)
would be pointless.
Instead, I strode to the blackboard and drew sketches of the
experimental design and the results of von Frisch's classic "step"
and "fan" experiments. I then highlighted the missing
controls and described how those same results fit an odor-search
model (e.g., Wenner 1971a, 1974; see also our chapter 5 and excursus
OS). The consequence was that I ended up questioning the entire
honey bee dance language hypothesis.
The audience reaction immediately turned from what might best
be termed one of euphoria to one of intense hostility. It was
certainly not the reaction one would have expected from an audience
of scientists. The reaction of Theodore Bullock, an eminent physiologist,
was fairly typical; he shouted: "What's the matter, don't
you believe anything unless you have done it yourself?"
Shortly thereafter the seminar ended. As far as I know, nothing
appeared in either the newspapers or on television, despite the
presence of all the media and the extensive film footage taken.
THE DINNER CONFERENCE
Bronowski had earlier informed me that a small group would have
dinner together and exchange views on honey bee dance language
research. That dinner party included several luminaries, including
Jonas Salk, Francis Crick, Jacques Monod, Jacob Bronowski, and
Theodore Bullock. Harald Esch, Irving Bengelsdorf (the Los
Angeles Times science editor), Harry Laidlaw, and a few others
were also present. After the dinner itself, the dishes were cleared
away and a rather intensive discussion of honey bee communication
began.
Eventually (by now unfettered by Bronowski's request that our
new experimental results not be presented), I began to describe
our conditioned-response experiments. I presented the results
of those experiments and indicated the significance of the experimental
results in terms of their importance to recruitment efficiency
in honey bees.
At one point I said, "One must consider the ecology of the
whole system, not just whatever behavior may occur between two
individual bees." At that point Bullock came forth with
another outburst, "Ecologists be damned, there's not a scientist
among the lot of them!"
The discussion became quite heated at that point, and many others
joined in. Bengelsdorf, who had remained quiet until that point,
finally said, "Wenner's correct; von Frisch's experiments
were not well enough controlled." (Bengelsdorf had a doctorate
in chemistry.) Shortly after that, Francis Crick leaned over
to Jonas Salk and said quietly (I was close enough to hear),
"Perhaps we had better not go ahead." The dinner engagement
was over shortly thereafter.
HARRY LAIDLAW'S INPUT
After returning to the hotel, I could not relax. Clearly something
had been transpiring about which I had not been informed. The
last comment directed to Salk by Crick indicated that something
big had been in the offing. Since Laidlaw had been a longtime
friend, I felt free to telephone him in his room and ask if he
knew what had been going on during dinner. He replied, "Yes,
didn't they tell you?"
He then came to my room and told me all he knew of what had been
planned. As he understood it, the Salk Institute, under Bronowski's
prompting, was interested primarily in the functioning of the
brain. The "instinctual signaling system" of bees appeared
to be an appropriate material for the investigation of brain
function. After all, that would be true if, as von Frisch had
said: The astoundingly precise adherence to the direction indicated,
regarded from the viewpoint of sensory physiology and psychology,
stands as a great accomplishment in reception and evaluation
of information" (1967a:231).
Apparently, Bronowski's brainchild" was to quick-freeze
a foraging bee while it was engaged in its dance maneuver; then
neural pathways could be traced. Other races of bees could be
used as well, and hybrids of those various races could be bred.
More freezing and slicing of brains could then be done at the
time of communication, and brain function could be elucidated
eventually.
What was the role of Esch in all of this activity? As we later
surmised, it appears that he was to have performed the field
experiments with the bees during their "bee language"
dance. The seminar was apparently what is known as a "recruitment"
seminar. Apparently my role as "discussant" was to
"legitimize" that activity and the project. In retrospect,
I concluded that it probably had eventually dawned on those present
at the dinner conference that the honey bee dance language hypothesis
may not have been on as solid a foundation as was stated by proponents
of that hypothesis.
THE STIMULUS FOR BETTER EXPERIMENTAL DESIGN
The Salk Institute experience provided an additional strong stimulus
for our further research on honey bee recruitment. Better experimental
designs were obviously needed for investigating honey bee recruitment
to food sources. We then gradually developed the more rigorous
double-control and "crucial" experimental designs (see
chapters 9 and 10). (It is also noteworthy that Gould and co-workers
later reverted to single-control experimental designs in their
"verification" approach; see chapter 13.)
Esch's seminar at the Salk Institute occurred in March 1966;
that very summer we set out to repeat von Frisch's original experiments.
Our eyes had been opened wider by now (we suddenly had new "spectacles").
We moved back to the "exploration" approach (Atkinson
1985; see also our figure 3.1) and away from our former "verification"
approach of attempting to "prove" that bees used sound
signals as part of their "dance language."
We already knew that we could obtain at will results similar
to those obtained by von Frisch. We also knew that several controls
were missing from von Frisch's experimental designs. The question
then became, "Were any essential controls missing
from von Frisch's experiments?"
That summer we repeated von Frisch's experiments many times and
with many variations. During that process we realized that his
single-control experimental design did not exclude the possibility
that searching recruit bees could exploit odors and the flight
paths of other bees during their search. While watching newly
recruited bees approach our feeding stations, we could clearly
see that they always approached from far downwind (the use of
binoculars helped). They obviously were not flying directly
out from the hive.
Through a trial-and-error process, we slowly came to the realization
that we could conduct a double-control experiment (a design rarely
used in field behavior experiments). That realization was facilitated
by the fact that we just happened to have another hive in the
area with its different color of bees. The experiments described
in chapter 9 were the outcome of all of those deliberations.
The trauma resulting from the Salk Institute encounter cannot
be described adequately; it is something that has to be experienced
to be believed (but not something one would wish on others).
However, sometimes it is an encounter of that sort that enables
one to appreciate fully some of the human elements involved in
the conduct of science. The Salk Institute affair may account
for the surprisingly confrontational attitude we encountered
at the Twenty-First International Apicultural Congress a few
months later and at subsequent national meetings.
The Salk Institute episode also apparently precipitated events
that led to experiments conducted by James Gould and co-workers
(see chapter 11).
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