The opposition to the honeybee DL hypothesis was launched by wenner's
team in print in 1967. But it soon met with a severe backlash, with DL
opponents being repeatedly denied access to print. Even Wenner's latest
article on this issue : The Elusive Honey Bee Dance "Language"
Hypothesis, published in Journal of Insect Behavior, Vol.
15, No. 6, November 2002. Pages 859-878 , (available on the Internet),
took (as I learned through an e-mail from Wenner), two and a half years
just to be accepted for publication.
Staunch DL sup****ters, i.e. guardians of the "established order", can
not of course do to us what the Vatican did to Galileo, i.e. they
cannot place our publications on the Index of Forbidden Books, i.e.
publications that are forbidden reading for "true believers". But they
do the second best thing. They avoid mentioning our publications, thus,
making those publications seem invisible. They concede that there is a
controversy over the very existence of the honeybee DL, only in
publications in which they provide yet another, presumably more
satisfactory experimental confirmation for the existenceof that DL.
Their latest, presumed superior "confirmation", is just as worthless as
all earlier "confirmations", but is immediately touted, with great
enthusiasm, in the popular scientific news-media.
The latest, in a very long list of studies claiming to have finally
achieved the fully convincing, essential experimental confirmation for
the existence of the honeybee DL, is the following re****t published a
little over half a year ago::
The flight paths of honeybees recruited by the waggle dance (2005).J.
R. Riley1 , U. Greggers2, A. D. Smith1, D. R. Reynolds 3 & R. Menzel2
NATURE, (12 MAY) VOL 435: 205-207.
The publication was immediately touted in the popular scientific
news-media all over the world, starting with the BBC. I shall not
summarize the publication here. Those interested can read publication
in the original journal. I shall, however, provide here my own re****t,
as a commentary:
To those interested:
Here is my final very brief analysis of the study by Riley et al.
(Nature, May 12, 2005), which claims to have experimentally confirmed,
by radar-tracking the flights of honeybee-recruits (in tests with a
single station, i.e. a foragers'-feeder), that the recruits used
distance & direction information contained in foragers'-dances about
the location of the foragers' food-source. What the authors apparently
discovered is that honeybees have the ability to use such information
only under conditions that never exist in nature.
The problems the researchers posed was whether honeybee-recruits do, or
do not use that information. For a reason, whose rational completely
escapes me, they used only unscented food, and did their best to avoid
contaminating the feeder-site with any other odors. The authors,
however, cite a statement by Tautz & Sandeman, to the effect that in
nature honeybee-recruits find, among others, also odorless sources,
such as water-sources, new nest-sites, and ivy-flowers. None of the
bees radar-tracked in the study showed any upwind zigzag (evidence for
a response to attractive odors), and none found either the food, or the
feeder. According to the published re****t, of the 19 bees fitted with a
transponder and released near the hive, for which radar-tracks are
available, 2 actually landed at the feeder.The re****t does not state
that they found the food, and as one of the authors (Greggers),
explained in an e-mail, they actually landed on the feeder-stand (a
chair), but they did not find the food, nor the feeder.
The answer to the problem the researchers posed has, however, been
known for a very long time, based on tests on honeybee-recruitment that
were done specifically with scented stations (where recruits arrived,
among others, at stations where they were not expected to arrive at
all, or where they never arrived at points where they were expected to
often arrive); had they used that distance & direction information.
1. In v. Frisch's first study on honeybee-recruitment (done with the
Austrian honeybee strain, and published in an extensive summary in
1923), the foragers performed only round dances without a trace of a
waggle. Had recruits used DL information they should (according to his
DL hypothesis), found stations only within 100 m. from the hive.
Instead, they found dishes with the foragers' food-odor 150 m. from the
hive in one test, 300 m. from the hive in another test, and 1,000 m.
from the hive (the greatest distance then tested), in yet another test.
2. We know that both distance-information & direction information for
any site, have a normal distribution. Recruits using the distance &
direction information contained in the dances, should, therefore, often
arrive (from the direction of the hive, and totallly irrespective of
wind-direction), at sites that are well within the odor-plumes from
stations, and much closer to the stations than the distance of 10 m
(which is the distance from which they can be easily spotted by
observers at stations with the ****d eye alone); all the more so if the
station happens to be the foragers'-station. Such recruits should then
start their upwind zigzag well within sight of observers, and arrive at
stations through the upwind zigzag from a far shorter distance than 10
m. away from a station. This expectation has never materialized.
Instead, when new-arrivals are first spotted by observers at stations,
the bees are invariably already zigzagging upwind toward the station.
(and when I say "invariably", I mean, based on observations on the
arrival of thousands of new bees at various stations, in many studies
by both DL sup****ters and DL opponents).
This typical manner of arrival was actually already known to v. Frisch
as early as 1920, as is obvious from a brief foot-note in his massive
1967 (original German edition of 1965), definitive book on the honeybee
DL. In that footnote he mentions the 3 new-bees that arrived at his
1,000 m. station in his first study on honeybee-recruitment. (This,
incidentally is the only ****tion of the results obtained in that study,
that are at all mentioned in the book, and it is very easy to miss,
because it deals with only 3 "measly" bees; unless you already know
that they form just the "tip of a huge iceberg", whose main bulk is not
even mentioned in the text of that book at all.)
The inevitable conclusion from these two types of results is that
honeybee-recruits do not use any DL information.
The results obtained by Riley et al. lead to the reverse conclusion.
And I am unable to explain those results without recourse to DL
information. (I could do that had the tracked bees been re-recruited
experienced foragers, but I shall skip the details, because this is not
the main point I want to stress here, and because the precautions taken
in the study exclude the possibility that those bees were anything
other than regular recruits; even though the 2 bees that landed on the
feeder-stand behaved the way regular recruits never do, and regular
recruits never behave the way those 2 bees did. (I shall skip the
details, as well as other problems with the results, again because this
is not at all the point I want to stress here.)
The point I want to stress, instead, is that the statement by Tautz &
Sandeman that recruits find odorless sources in nature is groundless.
In the natural environment where honeybees live, water, which they
obtain from the edges of ponds, or lakes, is never odorless; due to
odors from fresh vegetation near the water-edge, or from rotting
vegetation in the water. Nest-sites, in such an environment, are also
never odorless. In nature honeybees nest in cavities in the trunks of
trees in the woods. Such cavities invariably have the odors of
"wounded" wood, and are usually caused by a lighting strike. What about
the ivy-flowers? I asked Tautz about the source for his claim that in
nature honeybee-recruits find odorless ivy-flowers. His response (in an
e-mail), was that his information was based on old re****ts found in the
literature. Unfortunately, such old re****ts were based on v. Frisch's
erroneous conclusion of 1919, that honeybees had a very poor,
human-like sensitivity to odors; which in turn, led him to erroneously
also conclude that flowers which are odorless to humans must also be
odorless to honeybees. Ribbands was later (as detailed in his in 1954),
able to train foragers to the odors of such "odorless" flowers.
Moreover, Wenner, who was able to exclude environmental odors much
better than Riley et al. could (because he worked in Southern
California, which turns into a dry desert in summer), found out that no
new bees arrived anywhere near the site of his his forager's-feeder
(when he used a single forager to minimize honeybee-odors at the
feeder), and also excluded the last source of odors that still
attracted recruits, i.e. odors from commercial filter-paper that could
not be sensed by humans, but were obviously sensed by the bees. (The
test is re****ted in Wenner's 1971 book on the DL controversy.)
In short, honeybee-recruit do not find odorless sources in nature.
The inevitable conclusion is that Riley et al. discovered that
honeybees have an DL, which they can use only under conditions that
never occur in nature, i.e. when recruited to odorless sources. But,
this ability, disappears completely, as we already know very well, in
test with non-odorless sources.
I am quite willing to settle for this resolution of the DL controversy,
for the very simple reason that a honeybee DL that can not exist in
nature, i.e. in the real world, cannot exist at all!
Under the cir***stances, there is no doubt in my mind that there is
something wrong with the study by Riley et al. I have no idea what
might have gone wrong. And it is not my responsibility to solve this
problem regarding a study that I did not design, carry out, monitor, or
even witness. I was not there at all!
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