Last week Peter Dillon directed our attention to the following press item:
>http://news.bbc.co.uk/2/hi/science/nature/4536127.stm
I responded a week ago, in reference to the original "letter"
about radar tracking of bees that appeared in the journal Nature. I
posted the following note on BEE-L: "I have studied the original
Nature article (upon which the BBC article was based) and will
provide a considered response for BEE-L subscribers in due time. The
claims the authors made far exceeded the experimental results they
obtained."
Tracking recruited bees with radar to study their flight paths
after leaving the hive is a noble goal, provided the bees have not
been disturbed. Also, the experimenters should do so only if they
don't have a vested interest in the outcome; that is, that they
execute a true test of the language hypothesis. The authors failed
on both counts.
In the first few words of their report they used the phrase, "the
dance language," instead of more objective phrases, such as: "the
waggle dance," or "the dance maneuver." It became clear soon
thereafter in the paper that they start with an assumption of
language and then try to prove it.
First, some background. The researchers had some bees trained to
fly out to a feeding station and saw them later dance. They followed
a bee that attended such a dance, caught it as it left the hive,
attached a transponder onto its body, released it, and then followed
the path of that bee with radar. To conduct their study they
embraced a number of assumptions:
1) That a bee attending a dancer has the neurological/physiological
equipment to obtain abstract physical information from another bee.
2) That such a particular bee leaving a dancer "intends" to travel
to the "target" site.
3) The capture of a bee and fastening a transponder onto it doesn't
interfere with its "programmed" behavior.
4) The released bee doesn't execute an escape flight behavior,
perhaps toward some point on the distant horizon.
5) That they worked in an "odor free" area (odor free to bees) for
their experiments.
6) That experimental bees have a route memory of the feeding station
relative to the hive?
From the account published, it appears that some critical controls
were missing, including:
1) Data on flight paths of bees that had been similarly treated but
had not attended a dancer.
2) Data on flight paths of departing bees that had attended a dancer
that had visited food located in a different direction.
That is, the reasoning seems to be that, if the escaping bees fly
off in the "right" direction (the only direction arranged for), then
they have used their language. In fact, the Rothamsted group wrote
in October of 2003:
"We have used harmonic radar to measure the flight
trajectories of bees recruited after observing the
waggle dance, this has enabled us to settle (hopefully
once and for all) this controversy in favour of Von
Frisch."
What if, instead of continuing some sort of undefined programmed
behavior, all released bees had just executed an escape flight toward
some distant point on the horizon? (Translocating some other bees
before releasing them, as they did, then would not result in any
noticeable difference in flight behavior.)
All of the above reminds me of a 1971 statement by Nobel Laureate
Albert Szent-Gyorgyi (biochemistry): "If you know in advance what
you are going to do, or even to find there, then it is not research
at all: then it is only a kind of honorable occupation..."
What do beekeepers think? What percentage of them accept the
assumption that one can grab a bee, attach something to its body,
release it, and then expect it to go on its way as if nothing had
happened? In my experience, such a bee would fly an escape path and
would not likely continue a previously "programmed" behavior. Those
interested in what recruited bees normally might do after leaving the
hive can access:
http://www.beesource.com/pov/wenner/az1991.htm
That publication of ours contains several quotations by von Frisch
that stand in sharp contrast to the observations and claims made in
this latest Nature letter.
Some other questions might have occurred by now to other
beekeepers and bee researchers:
1) What about the very small sample size -- can the behavior of 19
disturbed bees undermine the results obtained from results obtained
from hundreds of unrestrained bees in double controlled and strong
inference experiments? (And, note, only two bees showed up near the
target station after some unspecified time delay.)
2) What about the behavior of the many other bees they must have
experimented upon. Surely they didn't just gather data from two
dozen bees and then quit when they had supportive evidence.
As is usual in such a case, some reporters contacted me for my
impressions. David Perlman of the San Francisco Chronicle recognized
that I had not had time to study the publication and came out with a
fairly accurate assessment in his article. Other reporters would not
accept my explanation that I would need a few days to study the
original publication, with a rather common comment: "I have a
deadline to meet."
No, I don't think that the behavior of 19 bees will resolve this
controversy, one that has run now for more than three decades. Nor
will beekeepers benefit from the claims made. They can go back to
worrying about varroa mites, small hive beetles, and other real
problems with, hopefully, some real solutions in the near future.
(Just think how much money and time was spent on this supposedly
final solution to the bee language controversy! Wouldn't that time
and effort have been better spent on breeding a varroa resistant bee?)
Adrian
--
Adrian M. Wenner (805) 963-8508 (home office phone)
967 Garcia Road [log in to unmask]
Santa Barbara, CA 93103 www.beesource.com/pov/wenner/index.htm
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* "...the intensity of the conviction that a hypothesis is true has
* no bearing on whether it is true or not."
*
* Peter Medawar (1979)
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