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By ADRIAN M. WENNER
Professor of Natural History, Emeritus,
Department of Biological Sciences
University of California, Santa Barbara,
Santa Barbara, California 93106
Abstract. Scientists normally receive very little formal
training in scientific method or in the philosophy, sociology
and psychology of science. Consequently, individual scientists
tend to become committed to hypotheses as end products rather
than as entities that will be replaced. Competing hypotheses
espoused by others then may lead to confrontation (controversy),
and application of the scientific method becomes a collective
and inefficient process. The on-going 25-year controversy about
the honey bee "dance language'' hypothesis serves as a good
example of how scientific progress is a process
instead of a series of accomplishments.
Science as Practiced vs. Science as Envisioned
Only rarely are academic biologists interested in the philosophy,
sociology and/or psychology of science-most often biologists
not only ignore deliberations of those scholars but scoff at
their efforts. It is no wonder that these subjects are not graduation
requirements for biology majors in most colleges and universities
throughout the country. Graduate students in biology fare little
better; graduate programs are built upon the premise that
the undergraduate curriculum has provided an adequate amount
of intellectual breadth. Graduate education largely consists
of an apprenticeship in the "objective" search for
knowledge.
Many scientists often scoff when they hear the phrase "scientific
method.'' Instead they rely upon narrow methodology such as ''verification''
or ''null hypothesis'' approaches in their research. That same
attitude is reflected in textbook treatment of "scientific
method'' (See Excursus SCI in Wenner and Wells 1990).
This unfortunate set of circumstances led Theocaris and Psimopoulos
to comment (p. 345 in Wenner and Wells 1990):
"The hapless student is inevitably left to his or her own
devices to pick up casually and randomly, from here and there,
unorganized bits of the scientific method, as well as bits of
unscientific methods.''
Scientific Process
One can argue that there must
be a scientific method if for no other reason than the fact of
a remarkable amount of scientific progress these past three centuries.
No other facet of our culture has exhibited a similar progression
in accumulation of knowledge. Furthermore, application of the
scientific method has become more effective through time and
has obviously been more efficient in some fields than in others
- witness the different rates of progress in the different areas
of science.

Despite the fact that individual scientists are not taught the
scientific method, scientific progress occurs - collectively
and inefficiently - by an unconscious group application of
a definable method. That method and its gradual evolution these
past few hundred years can be illustrated by a diagram, the details
of which can be found in Wenner (1989) and in Wenner
and Wells (1990; chapter 3).
The numbers attached to the names of people in Figure 1 represent
a sequence through time from Aristotle (~330 B.C.) to Atkinson
(in 1985). A short summary of the collective scientific
process follows (generally clockwise around the diagram).
Atkinson provided a thought that completed the picture for us.
An individualistic (creative) scientist generates some new perception
about nature when in the exploration mode (lower right
corner), often after having observed an anomaly in a set of results
during the progress of "normal" science. Recognition
of that anomaly permits a transition from an attitude of "Realism"
to "Relativism" - an interpretation considered ''fact
'' before is recognized as perhaps no longer adequate to explain
known facts. That scientist then "creates an image"
(in Atkinson's words) - forms an alternative explanation - and
attempts to convert others to the same point of view.
If others can be convinced, that scientist (perhaps others as
well) may try to verify the find (lower left corner of the diagram)
- a very necessary part of the process. For many, adequate verification
may suffice to establish "truth,'' but others might
insist on a test of the hypothesis and move either to the upper
left corner of the diagram (falsification approach) or
to the upper right corner (inference approach) and
test the hypothesis.
In some fields of science, a philosophy termed "logical
positivism" or "logical empiricism" (verification
and/or falsification approaches) dominated thinking about how
science should be done - textbook authors and workers in some
fields are still locked into those approaches. Thomas Kuhn sent
shock waves through the philosophical community in 1960 by
suggesting that science was not practiced solely by verification
and/or falsification. It was he who brought out most vividly
the importance of anomalies. Attention to an anomaly can propel
one out of the comfortable notion that we have a good perception
of reality and back into the exploration mode.
As far back as 1890, Thomas Chrowder Chamberlin recognized
the weakness of an over reliance on verification ("ruling
theory") and/or falsification (''working hypothesis''] methods.
He advocated instead an application of what he termed ''The Method
of Multiple Working Hypotheses," a process by which scientists
continually pit hypotheses against one another and attempt to
falsify all of them during experimentation. After results are
in, new alternative hypotheses are generated that might explain
known facts. Experiments are then designed to eliminate as many
hypotheses as possible. In that manner scientists continue recycling
ideas with no attempt to reach ultimate ''truth.''
Unfortunately, Chamberlin's thoughts disappeared from view until
the early 1960s when John Platt began to wonder why progress
was especially rapid in fields such as nuclear physics, genetics
and moulecular biology. He concluded that those fast moving fields
employed a ''strong inference'' approach - the equivalent of
moving up and down on the right half of the diagram - repeatedly
exploring and inferring without irrevocable commitment to given
hypotheses (paradigm hold). Platt persuaded Science to
re-publish Chamberlin's 1890 paper, a paper that is having ever
more impact with time.
The sum total of ideas contained in the theme diagram constitutes
the collective scientific process for scientists. Although fast
moving fields of science routinely include the strong inference
approach in their apprenticeship programs, scientists usually
conduct their research under quite different philosophies from
one another - each has a unique background, certain values and
set notions of procedure. Only rarely does one find a scientist
who can move from one approach to another with ease (as Pasteur
did). Duclaux, biographer of Pasteur, recognized the root problem
a hundred years ago: "However broad-minded one may be, he
is always to some extent the slave of his education and of his
past'' (p. 31 in Wenner and
Wells 1990).
Controversy as the "Fuel of Progress" in Science
One may try to "prove" (verify) a notion as an
irrefutable hypothesis and refuse to face the simple question,
''Is it conceivable that this hypothesis is not true?'' Alternatively,
we may go to a great amount of trouble phrasing a null hypothesis
and going through the motions of trying to prove that null hypothesis
true in an effort to defeat the hypothesis we have labored so
long to verify. Unfortunately, deep down inside we may really
like the hypothesis about to be tested (a paradigm hold)
and not want to see it negated by a critical test.
Another scientist may view a given set of results from another
perspective and controversy may erupt. In that sequence, one
person has a creative insight during exploration, generates a
hypothesis, and provides some verification for that hypothesis.
If the hypothesis is "attractive," others may accept
it. Given enough time, a subset of the scientific community may
treat that hypothesis (rather than the data) us ''fact'' and
therefore ''not open to question.'' When anomalies continue to
arise, either those anomalies are dismissed as unimportant, the
hypothesis is altered (and weakened), accessory hypotheses are
proposed that can explain away discrepancies, and/or supportive
evidence gets preferential treatment. All too often, new experiments
that provide additional verification may be considered ''definitive''
or ''elegant'' even when the hypothesis in question has failed
tests repeatedly. Science then slows to a near halt.
Science moves ahead again only when someone recognizes that an
anomaly simply cannot be dismissed, explores those implications,
and generates a new hypothesis that can explain all available
evidence better. However, the scientific community by then may
be too entrenched to recognize that the old hypothesis is no
longer adequate. The controversy that erupts eventually leads
to totally new types of research after the usual rush to confirm
(re-verify) the old hypothesis has subsided. In fast moving
fields of research, the time span can be measured in months or
years; in slow moving fields, decades may pass.
The Honey Bee Dance Language Controversy
The question of "language" among bees dates back centuries
with odor-search and ''language'' advocates firmly convinced
about their "final" answer each time. Karl von Frisch
proposed his waggle dance ''language'' hypothesis in 1946. Earlier,
though, in a 1937 article (in English) he strongly advocated
an odor-search hypothesis (Science Progress, reprinted
a year later in the Smithsonian Institution's 1938 Annual Report).
That 1937 article disappeared from all citation
lists after that time. (For example, he did not cite that contribution
in his classic 1946 paper nor in his massive 1967 review volume;
neither was it listed in the official list of publications at
the time of his death.)
The temporary loss of that early von Frisch article and his accumulated
knowledge to that time was very unfortunate in that it interfered
with science as process during the later bee language
controversy. Under the strong inference approach, both odor-search
and "language" hypotheses should have been kept as
viable options during experimentation (strong inference approach).
Just how the entire episode relates to our theme diagram is worth
elaborating upon here because of its implications for science
teaching. (For a more complete account, See Wenner and
Wells, 1990.)
In the more than two decades before his 1937 article, von Frisch
had patiently studied how naive bees are recruited to food sources
visited by experienced bees (foragers). In 1937 he wrote with
confidence:
". . . [recruited] bees
first seek in the neighborhood, and then go farther away, and
finally search the whole flying district. . . . I succeeded with
all kinds of flowers with the exception of flowers without any
scent . . . the scent of the flower is taken up by [the forager's]
body-surface and hairs, and when it dances after homing [then]
the interested bees . . . perceive the specific scent on its
body and know what kind of scent must be sought to find the good
feeding-place announced by the dancing bee. That this view is
correct can be proved easily . . ."
Later, von Frisch found that he could tell from elements in the
dance maneuver of successful bees just where they had been in
the field. On the basis of new experimental results (exploration
mode), he concluded that not only we but potential recruits could
"read" the dance maneuver and fly straight out to the
same site. With that verification, he published his classic 1946
paper on the "dance language" of honey bees. However,
he (and many others of us) failed to realize that results in
one section of his paper contradicted interpretation in another
section and vice versa.
In later experiments, "improved" experimental designs
actually funneled searching bees into the center of an array
(See Excursus PN in
Wenner and Wells 1990), leading von Frisch and others to
the notion that searching recruits "used" dance information
with great precision. Others using his experimental design could
easily get the same results (verification approach). This exotic
hypothesis then swept the world, even without ever having been
tested. (Exotic hypotheses are usually easier to "sell.")
Fifteen years after generation of the language hypothesis, I
noticed (awareness of anomaly) that information in the dance
maneuver was not sufficiently accurate to account for the "precision"
of recruit bee performance. Rather, random concentration of searchers
as a consequence of experimental design (as an odor field) could
explain his results. Later it became apparent (more anomaly)
that some evidence in support of "language" use (e.g.
in von Frisch's classic 1950 Cornell University Press book) had
actually been obtained by experimenting with bees that had been
re-recruited to familiar sources-bees that already knew the location
of the food source (recruitment by conditioned response, not
"language").
Eventually, my colleagues and I felt compelled to test, for the
first time, the dance language hypothesis. We used a double controlled
experimental design (falsification approach) and a "crucial"
experimental design (strong inference approach). The results
obtained clearly refuted the dance language hypothesis. However,
that evidence had little influence on the scientific community
- the hypothesis had become too deeply entrenched as "fact"
(the "ruling theory" of Chamberlin) and was "not
open to question." Instead of attending to the results of
our test, subsequent verification experiments by others provided
more supportive evidence for the language hypothesis.
I left bee research in the early 1970s but recently resumed research
in that area. There is now a willing audience for our newly formalized
odor-search hypothesis (based in part on von Frisch's 1937 contribution),
particularly among those engaged in applied research. The language
hypothesis has been of essentially no use to them in its 45 years
of existence, whereas the odor-search hypothesis has immediate
practical value - especially in countering the threat of Africanized
bees. There is also a possibility that the odor-search hypothesis
(e.g. chapter 5 and Excursus OS in Wenner and Wells 1990)
will be of immense practical value for those interested in honey
production and pollination of crops.
It is ironic that 56 years have now passed since von Frisch had
been so adamant that searching bees relied solely on odor cues.
We only hope that this episode can be used in teaching at all
levels to illustrate how science is a process rather than a series
of accomplishments (as it is so often taught).
Literature Cited
Chamberlin, T. C. The method of multiple working hypotheses.
Science 148:754-759; [1890] 1965.
Duclaux, E. Pasteur: the history of a mind. Trans. E. F. Smith
and F. Hedges. Philadelphia: W. B. Saunders; [1896] 1920.
Wenner. A. M. Concept-centered vs. organism-centered research.
American Zoologist 29:1177-1197; 1989.
Wenner. A. M.; Wells, P. H. Anatomy
of a controversy: the question of a "language" among
bees. New York: Columbia University Press; 1990. 400 pp.
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