J. theor. Biol. (1978) 72, 589-602
The Honey Bee “Language” R. Department
Controversy
ROSIN-~
of Zoology, The Hebrew
University
(Received 8 February
of Jerusalem, Israel
1977)
The controversy between the honey bee “language” hypothesis and the olfactory hypothesis, is essentially a controversy between a human-level hypothesis and an insect-level hypothesis, for an insect. A careful analysis of the theoretical process which underlies the design of experiments and interpretation of results, demonstrates that the proof that honey bees can use a “language” of abstract symbols, remains as inconclusive and nonvalid as ever.
1. Introduction The controversy between the von Frisch group’s “language” hypothesis (von Frisch, 1946, 1948, 1949, 1950, 1951, 1962, 1967a,b, 1968, 1973, 1974; Lindauer, 1961, 1971; Dawkins, 1969; Goncalves, 1969; Esch & Bastian, 1970; Gould et al., 1970; Mautz, 1971; Wilson, 1972; Gould, 1974, 1975; Krebs, 1975) and Wenner’s group’s olfactory hypothesis (Wenner, 1967, 1968, 1970, 1971, 1974; Johnson, 1967; Wenner et al., 1967; Wenner et al., 1969; Johnson & Wenner, 1970; Wells & Wenner, 1971, 1973, pers. comm.; Wenner et al., 1972; Friesen, 1973; Rosin, 1975) for the arrival of honey bee recruits at field sources, is essentially a controversy between a human-level hypothesis for an insect and an insect-level hypothesis for an insect. Since a hypothesis which claims a human-level “language” for an insect upsets the very foundation of behavior, and biology in general, the burden of the proof for the “language” hypothesis is, and always was, upon supporters of that hypothesis. The controversy has now reached a point where, although it is conceded that all previous results are accountable by use of odor, without recourse to “language”, we are, nonetheless, being offered a “conclusive” proof that honey bees use a “language” of abstract symbols, albeit only under “stress” (Gould, 1974, 1975). t Present
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The proof is, however, non-valid because (1) the experiments are based on a non-proven and non-tested basic hypothesis, and lack proper controls; (2) the interpretations of results are based on non-proven and non-tested secondary hypotheses; and (3) the results exhibit quite a number of details not compatible with use of “language”. All this tends to be easily lost in the multitude of detail. 2. The Basic Hypothesis
The whole design of the experiments is intended to separate between the effects of the right locale-odor and any possible effects of “language”. The attempt at separation is based on the basic hypothesis that honey bees correct for the deflecting effect which a directional light-source has on the direction of dances of normal foragers. Thus, a light-source was adjusted inside the hive, so as to cause a deflection of the direction of dances of normal foragers (from a control station), but have no effect on the dances of ocelli-treated foragers (from the forager-station). Under the basic assumption, since normal dance-attendants correct for the effect of the light-source, and since they cannot know whether the dances they attend are performed by normal or by ocelli-treated foragers, they will also correct the non-deflected dances of the ocelli-treated foragers, and will thus be directed away from the foraging-station, i.e. the right locale-odor station. The experimental stations were placed in accordance with this basic hypothesis. In the “Distance experiments” the whole array of experimental stations were restricted only to the direction presumably indicated to dance attendants by dances of the ocellitreated foragers. Except for a single intermediate station, no experimental stations were available in any other direction. In the “Direction experiments” the whole experimental array was restricted to the distance presumably indicated to dance-attendants by dances of the ocelli-treated foragers, i.e. assuming, a priori, that potential-recruits use the distance information from dances. In addition, the stations of the array were restricted to an arc of no more than 15” (for the 400 m experiments) and 62.5” (for the 150 m experiments) away from the direction presumably indicated to dance-attendants by dances of ocelli-treated foragers. However, since it is conceded that all previous results are accountable without recourse to “language”, this basic hypothesis remains non-proven, and one cannot base any experiments on it, without a proper test for the validity of this basic hypothesis, which would simultaneously test also the proof for use of “language”. A proper test would have been to add to each experiment a controlexperiment under exactly the same conditions, except for substituting non-
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treated foragers for ocelli-treated ones, in order to check whether the “treatment” has any effect at all on the distribution of new-arrivals. Another type of proper control would have been to compare the results of each experiment with the results of a control-experiment carried out under exactly the same conditions, except for the exclusion of the light-source (no point in using ocelli-treated foragers for this type of control). In order to equate wind-conditions, each pair of experiment and control, should, preferably, be carried out simultaneously, or while wind conditions remains the same. In addition, contrary to the practice employed in the study, of permitting anaesthesized new-arrivals to accumulate at the experimental stations, all new-arrivals should, preferably, be removed immediately, because their accumulation at the experimental stations opens the results to the effects of mere random chance. No such control-experiments are available. 3. Proper Controls
All the experiments involve all, or part, of the following five major factors: (1) Effects of right locale-odor at the forager-station. (The effects of this factor from the point of view of the olfactory hypothesis are obvious. They increase the probability of a potential-recruit arriving at such a station, as compared to the probability of arrival at a single, equal station, without this advantage.) (2) Effects of spatial design. (All the experiments had a markedly asymmetrical design, since they pitted a single forager station vs. a whole array of stations. It is obvious that spatial design must have an effect on the distribution of new-arrivals, because it affects the spatial distribution of the air-borne odor-plumes from the food-stations. In fact, the author’s “Wenner controls”, where the results are attributed by him to use of odor alone by most new-arrivals, in spite of the fact that it is not proven that even a single one of them used “language”, suffices to demonstrate that the specific spatial design per se, results in a majority of new-arrivals at the array.) This raises the question whether in the experiments using Gould’s technique, the very arrival of the majority at the array, is not due, again, to the same asymmetrical spatial design, irrespective of “language” information. (3) Effects of changes in spatial design during an experiment. (It is obvious that if the spatial design has an effect on the probability of recruit-arrival at the various stations, changes in the spatial design introduce changes in this probability.) (4) Effects of changing food-odor and raising food-concentration in the transition between training and experiment. (The effects of this complex
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factor on the probability of recruit-arrivals at the various stations, can only be partially evaluated, because the ontogenetic development of foraging behavior, and particularly the ontogenetic development of dance-attendance and the acquisition of attraction for the dancer’s odors, have not been sufficiently studied. It is obvious, however, that traces of training odor lingering in the locale of the forager-station, are attractive to those potential-recruits in the field, who attended dances and left the hive during training; whereas the new experimental odor at the forager-station, and at the array-stations, which were, themselves, introduced after training, is a strange odor for such bees, and therefore repellent to them (Free, 1969, 1970). The effects of traces of the training odor are even more complex, because such traces dissipate with time. On the other hand, it is obvious that raising food-concentration causes many potential dance-attendants, who did not attend dances during training, to attend dances during the experiment (hence the conspicuous rise in dance frequency), and thus acquire an attraction for the experimental odor (they may even, possibly, be repelled by traces of training odor at the locale of the forager-station, if traces of this odor are lost much faster from the foragers whose dances they attend; such a faster loss could, possibly, occur because foragers, contrary to the inanimate, stationary locale, are constantly washed by air-currents whose speed is relative to the speed of the foragers’ flight, and foragers also quickly distribute their food, and are thus rid of it). This partial discussion suffices to demonstrate that this factor has very complex effects from the point of view of the olfactory hypothesis. (5) Possible effects of “language” information. The issue at stake here is whether, as the author claims, point (5) has any effect on the distribution of new-arrivals, and point (4) only has an effect as an intermediary for the effects of point (5), i.e. whether point (4) only creates a “stress” situation which elicits a response to point (5). A brief examination of the original experiments, will suffice to demonstrate that they cannot serve as adequate controls for one another. Therefore, here is a brief representation of the combinations of major factors involved in each of the original experiments, as well as a representation of a proper control-experiment for each of the original ones (this is only one type of control out of many possible): Experiment type Distance experiments Basic Direction experiments Wenner controls von Frisch controls Integration experiments
Original experiments (factor combination)
(1)+(2)+(3)+(4)+(5) (1)+G+-W+@)+(5) (1)+(2)--W-(4+(3 (I)+(2)-(3)+(4)+(5) U+(2)+(3)+(4)+(5)
Control experiments (factor combination)
(1)+W+W+W+) W+W-~3)+@-~~) U+C9-(3)-W-W (l)+CWW+(+W (1)+(2)+W+W-(5)
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Here, as before, each experiment and its control should preferably be carried out while wind-conditions remain the same, and all new-arrivals removed upon arrival. Exclusion of factor (5), which differentiates the experiments from the controls, can be achieved by arranging for “language” information to indicate a location without a station(through proper adjustment ofthelight-source), or toindicateno specific location at all (through inducing non-directionaldances). Another possible type of proper control is based on the following consideration : Since it is conceded that all previous results are accountable by odor alone without recourse to “language”, this applies also to von Frisch’s well known “fan experiments”. In these experiments, a symmetrical arrangement of stations about the axis connecting the hive with the forager-station yielded a distribution of new-arrivals which was also symmetrical about the same axis. This is also to be expected according to the olfactory hypothesis, which views arrival of recruits as a probability matter. Thus, when the spatial design is symmetrical, then (barring bias due to asymmetrical wind-effects) the probability of recruit-arrivals at each of a pair of symmetrical stations is equal. Adding to the original spatial design, a second array in a symmetrical position on the other side of the axis connecting the hive with the foragerstation, can therefore serve as a proper control. The addition of the second array should have no effect, whatsoever, if bees use “language”, but it should have a profound effect, yielding symmetrical distributions of new-arrivals if bees use odor alone. (In the case of such a symmetrical control, wind-effects can be equated by repeating the experiment with side-alternation.) Any one proper control would have tested whether the results of the original experiments are due to effects of factor (5), or to the combined effects of (l)+ (2) + (3)+ (4), plus wind-effects, and plus effects of mere random chance due to accumulation of anaesthesized new-arrivals at the arraystations. (This last factor may require a brief explanation. Effects of mere random chance of new-arrivals are averaged out over a reasonably long counting period, but not necessarily over a short period. Thus, during a brief interval after the beginning of an experiment any distribution of new-arrivals may occur by mere random chance. However, since they add hive-odor, their initial accumulation in a random manner, may slightly bias all successive new-arrivals.) Not one single proper control is available. 4. Secondary Hypotheses
The concession regarding all previous results, as well as the author’s own interpretation of the results of his “Wenner controls”, simply mean con-
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ceding that new-arrivals can arrive, through use of odor alone, also at stations with the major experimental odors, but wrong locale-odor. (Incidentally, this concession also necessitates accepting a major claim of the olfactory hypothesis, i.e. that arrival of a potential-recruit, including whether it will arrive, and at which station it wiIl arrive, is a matter of probability. This is so, because only probability considerations can account for arrival of recruits, through use of odor alone, at both the right locale-odor station, as well as wrong locale-odor stations, which is exactly what happened in most previous experiments.) All new-arrivals at the array in all experiments which include the “stress” situation, i.e. all experiments except “Wenner controls”, are attributed by the author to use of “language”. However, such new-arrivals must have acquired, in the hive, a net attraction for the odors of the array-stations at which they arrived, since such an attraction is a pre-requisite for arrival according to both hypotheses. They, therefore, had both the odor-attraction and the ability needed for arrival through use of odor alone. Consequently, the dismissal of the possibility that they could have arrived, through odor alone, at any station of the array, including the right “language” station, by claiming that the conditions of the experiments create a “stress” situation which elicits use of “language”, is an arbitrary contention. Dismissal of new-arrivals at the “language’‘-wrong stations of the array, by claiming that they used “language”, but they use “language” with errors, is another arbitrary contention. Dismissal of new-arrivals at the foragerstation, i.e. “language’‘-wrong, but right locale-odor station, by claiming that under the same “stress” situation which presumably elicits use of “language”, some bees, nonetheless, use odor-alone, is yet another arbitrary contention. The many, who as in similar experiments on recruitment (Esch & Bastian, 1970; Gould et al., 1970; Mautz, 1971) probably did not arrive at all, were dismissed by simply not being studied. In a previous case (Gould et al., 1970) such non-arrivals were dismissed by the arbitrary contention that some bees just cannot use “language”, or else they tend to forget the “language” information. All these arbitrary contentions, are, in fact, no more than secondary hypotheses conjured in order to prop the primary “language” hypothesis. As such, each and every one of them is experimentally testable, e.g. by individually marking potential-recruits, capturing them after arrival or nonarrival, then putting them through additional experiments in order to verify whether their presumed “erring”, “forgetfulness”, “inability to use language”, are in any way consistent. At any rate, these secondary hypotheses cannot be accepted, unless each and every one of them is individually proven. Nor can any proof for the use of “language” which is based on these
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secondary hypotheses, be accepted unless the secondary hypotheses are proven. 5. Results not Compatible with Use of “Language”
The results of the studies which led to the presumably conclusive proof that honey bees use a “language” of abstract symbols, are impressive in that in the majority of cases presented, under “stress” the distributions of newarrivals indeed have a maximum at the array-station presumably indicated by “language”. Nonetheless, as stressed above, this in itself is no proof whatsoever that honey bees use “language”. Moreover, the results seem less impressive when it is realized that they are presented for only four “Direction experiments” (two “Basic Direction experiments” and two “von Frisch controls”) at 390-400 m, out of thirty-nine such experiments mentioned in the text. They become even less impressive when a detailed comparison of arrival-ratios for specific stations, is carred out. (The arrival-ratio for a specific station is defined as the ratio of the number of new-arrivals at that specific station for a particular distribution of new-arrivals, to the total number of new-arrivals for that particular distribution.) Thus, in the “Distance experiments”: (1) When “language” information presumably indicates the 180 m arraystation, the high arrival-ratio for the 150 m array-station (9/20) is, in fact, higher than the arrival-ratio for the 180 m station (g/20). (This is a comparison within the same distribution.) (2) When “language” information presumably indicates 60 m (there was no station at all at 60 m) the high arrival-ratio for the 90 m array-station (17/18 = 0.94) is, in fact, higher than the arrival-ratio for the same station when “language” information presumably indicates 90 m (18/22 = O-82). (This is a comparison from two distributions of the same experiment, i.e. under the same wind-conditions.) (A)
“VON
FRISCH
CONTROLS”
In these experiments, contrary to all others, the forager-station was placed very close to, and in the same direction as an array-station, and new-arrivals at the array-stations were neither anaesthesized, nor removed. In the first of these experiments (two counting periods whose results will be combined here), the forager-station was placed near a mid-station of the array, and the lightsource was so adjusted as not to deflect the direction of any dances. Hence “language” information presumably indicated the forager-station. In the second experiment, the forager-station was placed near an end-station of the array, and the light-source was SO adjusted, that “language” information
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presumably indicated a location very close to, and in the same direction as, the other end-station of the array. The author concludes that in the first experiment recruits displayed a stronger preference for the array-station closest to the forager-station (i.e. the array-station in the “correct” direction) than before (i.e. compared to the array-station in the “correct” distance and direction in the “Basic Direction experiments”, where the forager-station was at a completely different direction than any of the array-stations); whereas in the second experiment, they preferred both the array-station indicated by “language” (he is referring, in fact to the array-station in the direction presumably indicated by “language”) and the array-station nearest to the forager-station. However: (1) The high arrival-ratio for the array-station nearest to the forager station in the first experiment (77/280 = O-28) when the direction of that array-station (but not exact distance) is presumably indicated by “language”, is practically the same as the arrival-ratio for the array-station nearest to the forager-station in the second experiment (681266 = 0.25) when the direction of that array-station is presumably not indicated by “language”. (2) The high arrival-ratio for the forager-station itself in the first experiment (88/280 = 0.33) when this station is presumably indicated by “language”, is practically the same as it is in the second experiment (82/265 = 0.31) when this station is presumably not indicated by “language”. It should be noted that each of these last two comparisons were made for two different experiments, with different wind-conditions each. However, wind-conditions were not markedly different for both experiments; and situation, under which most besides, the experiments involved a “stress” potential-recruits presumably use “language” anyway, and use of “language” should not be affected by wind conditions. The comparisons of arrival-ratios demonstrate clearly, that new-arrivals who are presumably proven to have used “language”, in quite a number of cases arrive at a station equally well, irrespective of whether the station is presumably indicated by “language” or not. The author claims that we can have it “both ways”, i.e. that honey bees can use “language” under certain conditions and odor alone under other conditions, and that even under conditions where honey bees use “language”, some may still use odor alone (as he concludes from his studies). We cannot, however, have those honey bees which are presumably proven to have used “language”, sometimes behave in accordance with the presumed “language” information, and at other times in complete independence of that information. If they often do just as well without “language”, we must conclude that even in those cases where they seem to be affected by the presumed “language” information, the correlation
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is only incidental, and due to other factors which operate at the same time, but have nothing to do with “language”. The unavoidable conclusion is that honey bees do not use “language”, not even under “stress”. The results of the “von Frisch controls” when compared with one another, as well as with the results of the “Basic Direction experiments” using the same distance from the hive, in fact, clearly demonstrate the effect of the spatial design, and the effect that changes in the position of even one single station out of seven, has on the distribution of new-arrivals. Thus, the author ignores the need to view arrivals by odor alone as a probability matter, in spite of the fact that his own concession regarding all previous results requires accepting such a view. He also ignores the effects of spatial design and of changes in this design, in spite of the fact that his own results demonstrate the effect. He does not even conceive of effects of change in food-odor and raising food-concentration, on the probability of arrival. These effects include changes in the combinations of odors which potential-recruits must respond to in the field, as well as changes in the ontogenetic process of the individual development of foraging behavior (particularly the process which leads to dance-attendance and the acquisition of an attraction for the dancer’s odors). It is the importance of a detailed study of this process, for an understanding of foraging behavior in the honey bee, which I had already stressed before (Rosin, 1975).
6. “Language”
Efficiency
The study which led to the presumably conclusive proof that honey bees use a “language” of abstract symbols, also includes many other secondary conclusions. They all stem from the primary conclusion that under “stress” all new-arrivals at the array used “language”. All these secondary conclusions are, consequently, invalidated by the non-validity of the primary conclusion, and they will not be discussed here, except for the secondary conclusion regarding the presumed efficiency of the presumed use of “language”. The author concludes that not only did all new-arrivals at the array under “stress” use “language”, but that they used it with such great efficiency, that they arrived successfully after only a single dance-attendance. The proof that they attended a single dance is not valid, because it is derived from the results of the “Integration experiments” upon the basis of an erroneous conclusion from previous experiments that under “stress” honey bees use “language” in the first place, and on the basis of an arbitrary contention introduced by Lindauer (1971) that honey bees integrate “language” information from different dances. (This arbitrary contention, is, in fact, no other than a secondary hypothesis conjured in order to prop the primary
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“language” hypothesis in the face of the results of Wenner’s group’s “crucial experiment” (Wenner et al., 1969). As such, this secondary hypothesis is subject to experimental test, i.e. by using individually marked potentialrecruits, and observing directly what dances they attend and where they arrive. It was, in fact, never proven, nor even tested. Besdides, it becomes defunct even as a mere suggestion, due to the concession that all previous results are accountable without recourse to “language”.) The non-valid deduction of only a single dance attendance for new arrivals in the experiments using Gould’s technique, was achieved indirectly. The number of dances attended by any new-arrival can only be determined by use of individually marked potential-recruits and direct observation. Such a direct determination, which would have tested the validity of the indirect deduction, was not carried out. The claim that presumed “language” users attended only a single dance, is not quite borne by the experimental results either. This becomes evident when one compares recruiting-efficiency (i.e. number of new-arrivals per dance, for each counting period, i.e. for each distribution of new-arrivals). We find, first of all, that the total number of new-arrivals within each counting period, was invariably much higher for the “Wenner controls”, than for those of the “Basic Direction experiments” which use an exactly identical spatial design and counting periods of exactly the same duration, whereas the number of dances was in all cases, except one, much lower. This when in the “Wenner’s controls” most new-arrivals presumably used odor alone, but had a certain advantage due to an opportunity to attend dances with the experimental odor during training, while most new-arrivals in the “Basic Direction experiments”, and in fact all new-arrivals at the array in such experiments, presumably used “language”. The total number of arrivals is not indicative because it may vary from one case to another, with variations in the size of the population of potential-recruits available in the hive. The recruiting-efficiency, is found, however, to be invariably very much higher for the “Wenner’s controls” (2.2-3.8) than for those “Basic Direction experiments (0.43-0.68). Thus, it is much more likely that new-arrivals in those “Basic Direction experiments”, attended on the average many more dances than did new-arrivals in “Wenner’s controls”, because they had to make up for the lack of an opportunity to attend dances with the experimental odor during training, in order to be able to arrive by use of odor alone. The invalidation of high-efficiency for the presumed use of “language”, removes the basic rationale behind the claim that “language” is at all necessary, when honey bees can use odor alone with no lesser efficiency. In a way we are better off with the proof that honey bees use a “language” of abstract symbols rendered non-valid. Otherwise we would have had to face a much
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more difficult problem, i.e. that of explaining why, with the possession of such a sophisticated and efficient “language” mechanism, would honey bees not use it regularly. Instead, they were supposed to normally resort to use of odor alone, which entails attending dances (i.e. an opportunity to obtain “language” information) but requires many such dance-attendances, each followed by exit from the hive, and flight in the field, usually ending in a return to the hive, only to attend yet another dance and repeat the whole process. If we were to accept use of “language” only under very specilic conditions, as the author claims, we would have to accept the idea that the mechanism underlying such use of “language” is so rare and delicate that it is reserved only for special occasions. Indeed, it seems so rare and delicate that it does not exist at all. At any rate, so far no one has yet been able to prove its existence. 7. Conclusion A major statement made at the beginning of this article was that the controversy between the “language” hypothesis and the olfactory hypothesis is essentially a controversy between a human-level hypothesis and an insect-level hypothesis. In accordance with this statement, I have deviated, somewhat, from the original formulations of the olfactory hypothesis, and excluded any reference to “a search for the odor center” (Wenner, 1971) [this point had been justifiably criticized by von Frisch (1973)], nor to any search in a human sense at all. I have also excluded reference to an initial tight downwind “to within a confined range” (Wenner, 1974). The points I have deleted are not essential, and their deletion confines the olfactory hypothesis within an insect level. The “language” hypothesis, on the other hand, apart from attributing to honey bees a human-level “language”, also attributes to them a search for odor within a confined range (either as an initial step, when the dance is a “round dance”, or as a final step after use of “language”, when the dance is a “figure eight” dance), and a return to the hive if the odor is not found within the confined range. A search within a cotined range must be systematic, and this too requires no less than a human-level ability. The ability to obtain the “language” information in the first place, requires an ability to determine speed of dance-cycles, or dance-waggles, and the direction of a dance, in the dark, when dancers move constantly, and dance-attendants themselves are in constant motion, during which they do not, and cannot maintain a constant position in relation to the position of the dancer’s body, and when their contact with the dancer’s body is primarily through intermittent antenna1 taps, i.e. almost point contacts in which the points of contact vary from one dance-attendant to another at the same time, and for
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one and the same dance-attendant at different times. This again requires human-level capabilities, and would be a difficult task even for a human. The “language” hypothesis, in fact, requires many other capabilities on a human level, which do not, at all become obsolete by the concession that all previous results are accountable without recourse to “language”. [For a treatment of behavior in general and communication in particular, on the basis of phylogenetically different psychic levels, see Maier & Schneirla (1935, 1964) Tavolga (1969, 1970), Pie1 (1970) Atz (1970), Lehrman (1970).] The practice of attributing to honey bees, evermore behavioral traits on a par with a human level, has indeed become almost automatic for supporters of the “language” hypothesis, to the extent that they have enthusiastically already transferred a sense of “stress” to the honey bees. Although it might have seemed at first glance, that the ability of honey bees to use a “language” of abstract symbols, at least under highly specific conditions, has finally been conclusively proven, a detailed analysis of the theoretical process underlying the design of experiments and interpretation of results, demonstrates that the proof so far remains as inconclusive and non-valid as ever. This maintains honey bees at the state of ordinary insects, which may be somewhat disappointing. But then, it also retains our old fashioned phylogenetic system in a relatively intact state, which is no small consolation. REFERENCES AZ, J. W. (1970). In Development and Evolution of Behavior: Essays in Memory of’ T. C. Shneirla (L. R. Aronson, E. Tobach, D. S. Lehrman & J. S. Rosenblatt, eds) pp. 53-74. San Francisco : Freeman. DAWKINS, R. (1969). Science, 165, 751. ESCH, H. & BASTIAN, J. A. (1970). 2. Vgl. Physiul. 68, 175. FREE, J. B. (1969). Nature 222, 778. FREE, J. B. (1970). Behaviour 37, 269. VON FRISCH, K. (1946). Osterr. ZooI. 1, 1. Translated, 1947: Bull. Anim. Behav. 5, 1. VON FRISCH, K. (1948). Naturwiss. 35, 1,35,38. Translated, 1951: Bull. Anim. Behav. 9, 2. VON FRISCH, K. (1949). Experientia 5, 142. Translated, 1951: Bull. Anim. Behav. 9, 26. VON FRISCH, K. (1950). Bees: their Vision, Chemical Senses, and Language. Ithaca, New York: Cornell. VON FRISCH, K. (1951). Naturwiss. 38, 105. Translated, 1952: Bee World 33, 19. VON FRISCH, K. (1962). Sci. Am. August 207, 78. VON FRISCH, K. (1967a). The Dance Language and Orientation ofBees. Cambridge, Mass. : Harvard. VON FRLWH, K. (19676). Science 158,1072. VON FRIXH, K. (1968). Anim. Behav. 16, 531. VON FRISCH, K. (1973). Anim. Behdv. 21, 628. VON FRIXH, K. (1974). Science 184. 663. FRIPSEN, L. J. (1973). Biol. Bull. 144, 107. GONCALVES, L. S. (1969). J. apic, Res. 8, 113. GOULD, J. L. (1974). Nature 252,300. GOULD, J. L. (1975). Science 189,685.
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GOULD, J. L., HENEREY, M. & MACLEOD, M. C. (1970). Science 169,544. JOHNSON, D. L. (1967). Science 155,844. JOHNSON, D. L. & WENNER, A. M. (1970). .I. apic. Res. 9, 13. KREBS, J. R. (1975). Nature 258, 109. LEHRMAN, D. S. (1970). In Development and Evolution of Behavior, pp. 1 J-52. Ibid. LINDAUER, M. (1961). Communication among Social Bees. Cambridge, Mass. : Harvard. LINDAUER, M. (1971). Am. Nat. 105, 89. MAIER, N. R. F. & SCHNEIRLA, T. C. (1935). Principles of Animal Psychology. New York: McGraw-Hill. MAIER, N. R. F. & SCHNEIRLA, T. C. (1964). Principles of Animal Psychology. New York: Dover. MAUTZ, D. (1971). Z. Vgl. Physiol. 72,197. PIEL, G. (1970). In Development and Evohrtion of Behavior, pp. 1-13. Ibid. ROSIN, R. (1975). Science 188, 174. TAVOLGA, W. N. (1969). Principles of Animal Behavior. New York: Harper & Row. TAVOLGA, W. N. (1970). In Development and Evolution of Behavior, pp. 281-302. Ibid. WELLS, P. H. & WENNER, A. M. (1971). Physiof. Zoof. 44, 191. WELLS, P. H. & WENNER, A. M. (1973). Nature 241, 171. WENNER, A. M. (1967). Science 155, 847. WENNER, A. M. (1968). In Animal Communication (T. Sebeok, ed.), pp. 217-243. Bloomington, Indiana: Indiana University. WENNER, A. M. (1970). In McGrau?-Hill Yearbook of Science and Technology, pp. 110-113. New York: McGraw-Hill. WENNER, A. M. (1971). The Bee Language Controversy: An Experience in Science. Boulder, Colorado : Educational Programs Improvement Corporation. WENNER, A. M. (1974). In Nonverbal Commlmication (L. Krames, P. Pliner & T. Alloway, eds), pp. 133-169. New York, London: Plenum. WENNER, A. M., FRIESEN, L. J. & WELLS, P. H. (1972). Sci. Am. 227 no. 6, 6. WENNER, A. M. & JOHNSON, D. L. (1967). Science 158, 1076. WENNER, A. M., WELLS, P. H. & JOHNSON, D. L. (1969). Science 164,84. WENNER, A. M., WELLS, P. H. & ROHLF, F. J. (1967). Ph.ysiof. Zoo/. 40, 317. WILSON, E. 0. (1972). Sri. Am. 227 no. 6, 6.
Note added in proqj’
Two more publications on the issuehave come to my attention: GOULD, L. (1975). J. camp. Physiol. 104, 161, and GOULD, J. L. (1976). Q. rev. Biol. 51, 211. The first of these reports on additional “Direction experiments”, including “Wenner controls”, and is subject to the same type of criticism presented in this paper. The second publication claims that the author’s interpretation of his experimental results is conclusively proven, becauseno alternative explanation based on odor alone is presumably possible. The publication also, prematurely, views the controversy as already closed in favor of the “dance language” hypothesis. However, the possibility of an alternative explanation based on odor alone has never been properly investigated. (A proper investigation would have required investigating the effects of a whole variety of possible factors on use of odor alone.) The possibility that no other explanaJ.
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tion except one based on odor alone might be acceptable has never been properly tested either. (The test requires including the proper controls.) At the same time, the author’s interpretation is unacceptable on its own merit. It cannot account for results that are incompatible with it; it cannot explain why under “stress”, which presumably elicits use of “language”, some bees still use odor alone; and it cannot explain why users of odor alone who can arrive at all stations (including stations of the array), are barred from the array under “stress”.
The Honey Bee “Language” R. Department
Controversy
ROSIN-~
of Zoology, The Hebrew
University
(Received 8 February
of Jerusalem, Israel
1977)
The controversy between the honey bee “language” hypothesis and the olfactory hypothesis, is essentially a controversy between a human-level hypothesis and an insect-level hypothesis, for an insect. A careful analysis of the theoretical process which underlies the design of experiments and interpretation of results, demonstrates that the proof that honey bees can use a “language” of abstract symbols, remains as inconclusive and nonvalid as ever.
1. Introduction The controversy between the von Frisch group’s “language” hypothesis (von Frisch, 1946, 1948, 1949, 1950, 1951, 1962, 1967a,b, 1968, 1973, 1974; Lindauer, 1961, 1971; Dawkins, 1969; Goncalves, 1969; Esch & Bastian, 1970; Gould et al., 1970; Mautz, 1971; Wilson, 1972; Gould, 1974, 1975; Krebs, 1975) and Wenner’s group’s olfactory hypothesis (Wenner, 1967, 1968, 1970, 1971, 1974; Johnson, 1967; Wenner et al., 1967; Wenner et al., 1969; Johnson & Wenner, 1970; Wells & Wenner, 1971, 1973, pers. comm.; Wenner et al., 1972; Friesen, 1973; Rosin, 1975) for the arrival of honey bee recruits at field sources, is essentially a controversy between a human-level hypothesis for an insect and an insect-level hypothesis for an insect. Since a hypothesis which claims a human-level “language” for an insect upsets the very foundation of behavior, and biology in general, the burden of the proof for the “language” hypothesis is, and always was, upon supporters of that hypothesis. The controversy has now reached a point where, although it is conceded that all previous results are accountable by use of odor, without recourse to “language”, we are, nonetheless, being offered a “conclusive” proof that honey bees use a “language” of abstract symbols, albeit only under “stress” (Gould, 1974, 1975). t Present
address:
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The proof is, however, non-valid because (1) the experiments are based on a non-proven and non-tested basic hypothesis, and lack proper controls; (2) the interpretations of results are based on non-proven and non-tested secondary hypotheses; and (3) the results exhibit quite a number of details not compatible with use of “language”. All this tends to be easily lost in the multitude of detail. 2. The Basic Hypothesis
The whole design of the experiments is intended to separate between the effects of the right locale-odor and any possible effects of “language”. The attempt at separation is based on the basic hypothesis that honey bees correct for the deflecting effect which a directional light-source has on the direction of dances of normal foragers. Thus, a light-source was adjusted inside the hive, so as to cause a deflection of the direction of dances of normal foragers (from a control station), but have no effect on the dances of ocelli-treated foragers (from the forager-station). Under the basic assumption, since normal dance-attendants correct for the effect of the light-source, and since they cannot know whether the dances they attend are performed by normal or by ocelli-treated foragers, they will also correct the non-deflected dances of the ocelli-treated foragers, and will thus be directed away from the foraging-station, i.e. the right locale-odor station. The experimental stations were placed in accordance with this basic hypothesis. In the “Distance experiments” the whole array of experimental stations were restricted only to the direction presumably indicated to dance attendants by dances of the ocellitreated foragers. Except for a single intermediate station, no experimental stations were available in any other direction. In the “Direction experiments” the whole experimental array was restricted to the distance presumably indicated to dance-attendants by dances of the ocelli-treated foragers, i.e. assuming, a priori, that potential-recruits use the distance information from dances. In addition, the stations of the array were restricted to an arc of no more than 15” (for the 400 m experiments) and 62.5” (for the 150 m experiments) away from the direction presumably indicated to dance-attendants by dances of ocelli-treated foragers. However, since it is conceded that all previous results are accountable without recourse to “language”, this basic hypothesis remains non-proven, and one cannot base any experiments on it, without a proper test for the validity of this basic hypothesis, which would simultaneously test also the proof for use of “language”. A proper test would have been to add to each experiment a controlexperiment under exactly the same conditions, except for substituting non-
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treated foragers for ocelli-treated ones, in order to check whether the “treatment” has any effect at all on the distribution of new-arrivals. Another type of proper control would have been to compare the results of each experiment with the results of a control-experiment carried out under exactly the same conditions, except for the exclusion of the light-source (no point in using ocelli-treated foragers for this type of control). In order to equate wind-conditions, each pair of experiment and control, should, preferably, be carried out simultaneously, or while wind conditions remains the same. In addition, contrary to the practice employed in the study, of permitting anaesthesized new-arrivals to accumulate at the experimental stations, all new-arrivals should, preferably, be removed immediately, because their accumulation at the experimental stations opens the results to the effects of mere random chance. No such control-experiments are available. 3. Proper Controls
All the experiments involve all, or part, of the following five major factors: (1) Effects of right locale-odor at the forager-station. (The effects of this factor from the point of view of the olfactory hypothesis are obvious. They increase the probability of a potential-recruit arriving at such a station, as compared to the probability of arrival at a single, equal station, without this advantage.) (2) Effects of spatial design. (All the experiments had a markedly asymmetrical design, since they pitted a single forager station vs. a whole array of stations. It is obvious that spatial design must have an effect on the distribution of new-arrivals, because it affects the spatial distribution of the air-borne odor-plumes from the food-stations. In fact, the author’s “Wenner controls”, where the results are attributed by him to use of odor alone by most new-arrivals, in spite of the fact that it is not proven that even a single one of them used “language”, suffices to demonstrate that the specific spatial design per se, results in a majority of new-arrivals at the array.) This raises the question whether in the experiments using Gould’s technique, the very arrival of the majority at the array, is not due, again, to the same asymmetrical spatial design, irrespective of “language” information. (3) Effects of changes in spatial design during an experiment. (It is obvious that if the spatial design has an effect on the probability of recruit-arrival at the various stations, changes in the spatial design introduce changes in this probability.) (4) Effects of changing food-odor and raising food-concentration in the transition between training and experiment. (The effects of this complex
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factor on the probability of recruit-arrivals at the various stations, can only be partially evaluated, because the ontogenetic development of foraging behavior, and particularly the ontogenetic development of dance-attendance and the acquisition of attraction for the dancer’s odors, have not been sufficiently studied. It is obvious, however, that traces of training odor lingering in the locale of the forager-station, are attractive to those potential-recruits in the field, who attended dances and left the hive during training; whereas the new experimental odor at the forager-station, and at the array-stations, which were, themselves, introduced after training, is a strange odor for such bees, and therefore repellent to them (Free, 1969, 1970). The effects of traces of the training odor are even more complex, because such traces dissipate with time. On the other hand, it is obvious that raising food-concentration causes many potential dance-attendants, who did not attend dances during training, to attend dances during the experiment (hence the conspicuous rise in dance frequency), and thus acquire an attraction for the experimental odor (they may even, possibly, be repelled by traces of training odor at the locale of the forager-station, if traces of this odor are lost much faster from the foragers whose dances they attend; such a faster loss could, possibly, occur because foragers, contrary to the inanimate, stationary locale, are constantly washed by air-currents whose speed is relative to the speed of the foragers’ flight, and foragers also quickly distribute their food, and are thus rid of it). This partial discussion suffices to demonstrate that this factor has very complex effects from the point of view of the olfactory hypothesis. (5) Possible effects of “language” information. The issue at stake here is whether, as the author claims, point (5) has any effect on the distribution of new-arrivals, and point (4) only has an effect as an intermediary for the effects of point (5), i.e. whether point (4) only creates a “stress” situation which elicits a response to point (5). A brief examination of the original experiments, will suffice to demonstrate that they cannot serve as adequate controls for one another. Therefore, here is a brief representation of the combinations of major factors involved in each of the original experiments, as well as a representation of a proper control-experiment for each of the original ones (this is only one type of control out of many possible): Experiment type Distance experiments Basic Direction experiments Wenner controls von Frisch controls Integration experiments
Original experiments (factor combination)
(1)+(2)+(3)+(4)+(5) (1)+G+-W+@)+(5) (1)+(2)--W-(4+(3 (I)+(2)-(3)+(4)+(5) U+(2)+(3)+(4)+(5)
Control experiments (factor combination)
(1)+W+W+W+) W+W-~3)+@-~~) U+C9-(3)-W-W (l)+CWW+(+W (1)+(2)+W+W-(5)
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Here, as before, each experiment and its control should preferably be carried out while wind-conditions remain the same, and all new-arrivals removed upon arrival. Exclusion of factor (5), which differentiates the experiments from the controls, can be achieved by arranging for “language” information to indicate a location without a station(through proper adjustment ofthelight-source), or toindicateno specific location at all (through inducing non-directionaldances). Another possible type of proper control is based on the following consideration : Since it is conceded that all previous results are accountable by odor alone without recourse to “language”, this applies also to von Frisch’s well known “fan experiments”. In these experiments, a symmetrical arrangement of stations about the axis connecting the hive with the forager-station yielded a distribution of new-arrivals which was also symmetrical about the same axis. This is also to be expected according to the olfactory hypothesis, which views arrival of recruits as a probability matter. Thus, when the spatial design is symmetrical, then (barring bias due to asymmetrical wind-effects) the probability of recruit-arrivals at each of a pair of symmetrical stations is equal. Adding to the original spatial design, a second array in a symmetrical position on the other side of the axis connecting the hive with the foragerstation, can therefore serve as a proper control. The addition of the second array should have no effect, whatsoever, if bees use “language”, but it should have a profound effect, yielding symmetrical distributions of new-arrivals if bees use odor alone. (In the case of such a symmetrical control, wind-effects can be equated by repeating the experiment with side-alternation.) Any one proper control would have tested whether the results of the original experiments are due to effects of factor (5), or to the combined effects of (l)+ (2) + (3)+ (4), plus wind-effects, and plus effects of mere random chance due to accumulation of anaesthesized new-arrivals at the arraystations. (This last factor may require a brief explanation. Effects of mere random chance of new-arrivals are averaged out over a reasonably long counting period, but not necessarily over a short period. Thus, during a brief interval after the beginning of an experiment any distribution of new-arrivals may occur by mere random chance. However, since they add hive-odor, their initial accumulation in a random manner, may slightly bias all successive new-arrivals.) Not one single proper control is available. 4. Secondary Hypotheses
The concession regarding all previous results, as well as the author’s own interpretation of the results of his “Wenner controls”, simply mean con-
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ceding that new-arrivals can arrive, through use of odor alone, also at stations with the major experimental odors, but wrong locale-odor. (Incidentally, this concession also necessitates accepting a major claim of the olfactory hypothesis, i.e. that arrival of a potential-recruit, including whether it will arrive, and at which station it wiIl arrive, is a matter of probability. This is so, because only probability considerations can account for arrival of recruits, through use of odor alone, at both the right locale-odor station, as well as wrong locale-odor stations, which is exactly what happened in most previous experiments.) All new-arrivals at the array in all experiments which include the “stress” situation, i.e. all experiments except “Wenner controls”, are attributed by the author to use of “language”. However, such new-arrivals must have acquired, in the hive, a net attraction for the odors of the array-stations at which they arrived, since such an attraction is a pre-requisite for arrival according to both hypotheses. They, therefore, had both the odor-attraction and the ability needed for arrival through use of odor alone. Consequently, the dismissal of the possibility that they could have arrived, through odor alone, at any station of the array, including the right “language” station, by claiming that the conditions of the experiments create a “stress” situation which elicits use of “language”, is an arbitrary contention. Dismissal of new-arrivals at the “language’‘-wrong stations of the array, by claiming that they used “language”, but they use “language” with errors, is another arbitrary contention. Dismissal of new-arrivals at the foragerstation, i.e. “language’‘-wrong, but right locale-odor station, by claiming that under the same “stress” situation which presumably elicits use of “language”, some bees, nonetheless, use odor-alone, is yet another arbitrary contention. The many, who as in similar experiments on recruitment (Esch & Bastian, 1970; Gould et al., 1970; Mautz, 1971) probably did not arrive at all, were dismissed by simply not being studied. In a previous case (Gould et al., 1970) such non-arrivals were dismissed by the arbitrary contention that some bees just cannot use “language”, or else they tend to forget the “language” information. All these arbitrary contentions, are, in fact, no more than secondary hypotheses conjured in order to prop the primary “language” hypothesis. As such, each and every one of them is experimentally testable, e.g. by individually marking potential-recruits, capturing them after arrival or nonarrival, then putting them through additional experiments in order to verify whether their presumed “erring”, “forgetfulness”, “inability to use language”, are in any way consistent. At any rate, these secondary hypotheses cannot be accepted, unless each and every one of them is individually proven. Nor can any proof for the use of “language” which is based on these
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secondary hypotheses, be accepted unless the secondary hypotheses are proven. 5. Results not Compatible with Use of “Language”
The results of the studies which led to the presumably conclusive proof that honey bees use a “language” of abstract symbols, are impressive in that in the majority of cases presented, under “stress” the distributions of newarrivals indeed have a maximum at the array-station presumably indicated by “language”. Nonetheless, as stressed above, this in itself is no proof whatsoever that honey bees use “language”. Moreover, the results seem less impressive when it is realized that they are presented for only four “Direction experiments” (two “Basic Direction experiments” and two “von Frisch controls”) at 390-400 m, out of thirty-nine such experiments mentioned in the text. They become even less impressive when a detailed comparison of arrival-ratios for specific stations, is carred out. (The arrival-ratio for a specific station is defined as the ratio of the number of new-arrivals at that specific station for a particular distribution of new-arrivals, to the total number of new-arrivals for that particular distribution.) Thus, in the “Distance experiments”: (1) When “language” information presumably indicates the 180 m arraystation, the high arrival-ratio for the 150 m array-station (9/20) is, in fact, higher than the arrival-ratio for the 180 m station (g/20). (This is a comparison within the same distribution.) (2) When “language” information presumably indicates 60 m (there was no station at all at 60 m) the high arrival-ratio for the 90 m array-station (17/18 = 0.94) is, in fact, higher than the arrival-ratio for the same station when “language” information presumably indicates 90 m (18/22 = O-82). (This is a comparison from two distributions of the same experiment, i.e. under the same wind-conditions.) (A)
“VON
FRISCH
CONTROLS”
In these experiments, contrary to all others, the forager-station was placed very close to, and in the same direction as an array-station, and new-arrivals at the array-stations were neither anaesthesized, nor removed. In the first of these experiments (two counting periods whose results will be combined here), the forager-station was placed near a mid-station of the array, and the lightsource was so adjusted as not to deflect the direction of any dances. Hence “language” information presumably indicated the forager-station. In the second experiment, the forager-station was placed near an end-station of the array, and the light-source was SO adjusted, that “language” information
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presumably indicated a location very close to, and in the same direction as, the other end-station of the array. The author concludes that in the first experiment recruits displayed a stronger preference for the array-station closest to the forager-station (i.e. the array-station in the “correct” direction) than before (i.e. compared to the array-station in the “correct” distance and direction in the “Basic Direction experiments”, where the forager-station was at a completely different direction than any of the array-stations); whereas in the second experiment, they preferred both the array-station indicated by “language” (he is referring, in fact to the array-station in the direction presumably indicated by “language”) and the array-station nearest to the forager-station. However: (1) The high arrival-ratio for the array-station nearest to the forager station in the first experiment (77/280 = O-28) when the direction of that array-station (but not exact distance) is presumably indicated by “language”, is practically the same as the arrival-ratio for the array-station nearest to the forager-station in the second experiment (681266 = 0.25) when the direction of that array-station is presumably not indicated by “language”. (2) The high arrival-ratio for the forager-station itself in the first experiment (88/280 = 0.33) when this station is presumably indicated by “language”, is practically the same as it is in the second experiment (82/265 = 0.31) when this station is presumably not indicated by “language”. It should be noted that each of these last two comparisons were made for two different experiments, with different wind-conditions each. However, wind-conditions were not markedly different for both experiments; and situation, under which most besides, the experiments involved a “stress” potential-recruits presumably use “language” anyway, and use of “language” should not be affected by wind conditions. The comparisons of arrival-ratios demonstrate clearly, that new-arrivals who are presumably proven to have used “language”, in quite a number of cases arrive at a station equally well, irrespective of whether the station is presumably indicated by “language” or not. The author claims that we can have it “both ways”, i.e. that honey bees can use “language” under certain conditions and odor alone under other conditions, and that even under conditions where honey bees use “language”, some may still use odor alone (as he concludes from his studies). We cannot, however, have those honey bees which are presumably proven to have used “language”, sometimes behave in accordance with the presumed “language” information, and at other times in complete independence of that information. If they often do just as well without “language”, we must conclude that even in those cases where they seem to be affected by the presumed “language” information, the correlation
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is only incidental, and due to other factors which operate at the same time, but have nothing to do with “language”. The unavoidable conclusion is that honey bees do not use “language”, not even under “stress”. The results of the “von Frisch controls” when compared with one another, as well as with the results of the “Basic Direction experiments” using the same distance from the hive, in fact, clearly demonstrate the effect of the spatial design, and the effect that changes in the position of even one single station out of seven, has on the distribution of new-arrivals. Thus, the author ignores the need to view arrivals by odor alone as a probability matter, in spite of the fact that his own concession regarding all previous results requires accepting such a view. He also ignores the effects of spatial design and of changes in this design, in spite of the fact that his own results demonstrate the effect. He does not even conceive of effects of change in food-odor and raising food-concentration, on the probability of arrival. These effects include changes in the combinations of odors which potential-recruits must respond to in the field, as well as changes in the ontogenetic process of the individual development of foraging behavior (particularly the process which leads to dance-attendance and the acquisition of an attraction for the dancer’s odors). It is the importance of a detailed study of this process, for an understanding of foraging behavior in the honey bee, which I had already stressed before (Rosin, 1975).
6. “Language”
Efficiency
The study which led to the presumably conclusive proof that honey bees use a “language” of abstract symbols, also includes many other secondary conclusions. They all stem from the primary conclusion that under “stress” all new-arrivals at the array used “language”. All these secondary conclusions are, consequently, invalidated by the non-validity of the primary conclusion, and they will not be discussed here, except for the secondary conclusion regarding the presumed efficiency of the presumed use of “language”. The author concludes that not only did all new-arrivals at the array under “stress” use “language”, but that they used it with such great efficiency, that they arrived successfully after only a single dance-attendance. The proof that they attended a single dance is not valid, because it is derived from the results of the “Integration experiments” upon the basis of an erroneous conclusion from previous experiments that under “stress” honey bees use “language” in the first place, and on the basis of an arbitrary contention introduced by Lindauer (1971) that honey bees integrate “language” information from different dances. (This arbitrary contention, is, in fact, no other than a secondary hypothesis conjured in order to prop the primary
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“language” hypothesis in the face of the results of Wenner’s group’s “crucial experiment” (Wenner et al., 1969). As such, this secondary hypothesis is subject to experimental test, i.e. by using individually marked potentialrecruits, and observing directly what dances they attend and where they arrive. It was, in fact, never proven, nor even tested. Besdides, it becomes defunct even as a mere suggestion, due to the concession that all previous results are accountable without recourse to “language”.) The non-valid deduction of only a single dance attendance for new arrivals in the experiments using Gould’s technique, was achieved indirectly. The number of dances attended by any new-arrival can only be determined by use of individually marked potential-recruits and direct observation. Such a direct determination, which would have tested the validity of the indirect deduction, was not carried out. The claim that presumed “language” users attended only a single dance, is not quite borne by the experimental results either. This becomes evident when one compares recruiting-efficiency (i.e. number of new-arrivals per dance, for each counting period, i.e. for each distribution of new-arrivals). We find, first of all, that the total number of new-arrivals within each counting period, was invariably much higher for the “Wenner controls”, than for those of the “Basic Direction experiments” which use an exactly identical spatial design and counting periods of exactly the same duration, whereas the number of dances was in all cases, except one, much lower. This when in the “Wenner’s controls” most new-arrivals presumably used odor alone, but had a certain advantage due to an opportunity to attend dances with the experimental odor during training, while most new-arrivals in the “Basic Direction experiments”, and in fact all new-arrivals at the array in such experiments, presumably used “language”. The total number of arrivals is not indicative because it may vary from one case to another, with variations in the size of the population of potential-recruits available in the hive. The recruiting-efficiency, is found, however, to be invariably very much higher for the “Wenner’s controls” (2.2-3.8) than for those “Basic Direction experiments (0.43-0.68). Thus, it is much more likely that new-arrivals in those “Basic Direction experiments”, attended on the average many more dances than did new-arrivals in “Wenner’s controls”, because they had to make up for the lack of an opportunity to attend dances with the experimental odor during training, in order to be able to arrive by use of odor alone. The invalidation of high-efficiency for the presumed use of “language”, removes the basic rationale behind the claim that “language” is at all necessary, when honey bees can use odor alone with no lesser efficiency. In a way we are better off with the proof that honey bees use a “language” of abstract symbols rendered non-valid. Otherwise we would have had to face a much
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more difficult problem, i.e. that of explaining why, with the possession of such a sophisticated and efficient “language” mechanism, would honey bees not use it regularly. Instead, they were supposed to normally resort to use of odor alone, which entails attending dances (i.e. an opportunity to obtain “language” information) but requires many such dance-attendances, each followed by exit from the hive, and flight in the field, usually ending in a return to the hive, only to attend yet another dance and repeat the whole process. If we were to accept use of “language” only under very specilic conditions, as the author claims, we would have to accept the idea that the mechanism underlying such use of “language” is so rare and delicate that it is reserved only for special occasions. Indeed, it seems so rare and delicate that it does not exist at all. At any rate, so far no one has yet been able to prove its existence. 7. Conclusion A major statement made at the beginning of this article was that the controversy between the “language” hypothesis and the olfactory hypothesis is essentially a controversy between a human-level hypothesis and an insect-level hypothesis. In accordance with this statement, I have deviated, somewhat, from the original formulations of the olfactory hypothesis, and excluded any reference to “a search for the odor center” (Wenner, 1971) [this point had been justifiably criticized by von Frisch (1973)], nor to any search in a human sense at all. I have also excluded reference to an initial tight downwind “to within a confined range” (Wenner, 1974). The points I have deleted are not essential, and their deletion confines the olfactory hypothesis within an insect level. The “language” hypothesis, on the other hand, apart from attributing to honey bees a human-level “language”, also attributes to them a search for odor within a confined range (either as an initial step, when the dance is a “round dance”, or as a final step after use of “language”, when the dance is a “figure eight” dance), and a return to the hive if the odor is not found within the confined range. A search within a cotined range must be systematic, and this too requires no less than a human-level ability. The ability to obtain the “language” information in the first place, requires an ability to determine speed of dance-cycles, or dance-waggles, and the direction of a dance, in the dark, when dancers move constantly, and dance-attendants themselves are in constant motion, during which they do not, and cannot maintain a constant position in relation to the position of the dancer’s body, and when their contact with the dancer’s body is primarily through intermittent antenna1 taps, i.e. almost point contacts in which the points of contact vary from one dance-attendant to another at the same time, and for
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one and the same dance-attendant at different times. This again requires human-level capabilities, and would be a difficult task even for a human. The “language” hypothesis, in fact, requires many other capabilities on a human level, which do not, at all become obsolete by the concession that all previous results are accountable without recourse to “language”. [For a treatment of behavior in general and communication in particular, on the basis of phylogenetically different psychic levels, see Maier & Schneirla (1935, 1964) Tavolga (1969, 1970), Pie1 (1970) Atz (1970), Lehrman (1970).] The practice of attributing to honey bees, evermore behavioral traits on a par with a human level, has indeed become almost automatic for supporters of the “language” hypothesis, to the extent that they have enthusiastically already transferred a sense of “stress” to the honey bees. Although it might have seemed at first glance, that the ability of honey bees to use a “language” of abstract symbols, at least under highly specific conditions, has finally been conclusively proven, a detailed analysis of the theoretical process underlying the design of experiments and interpretation of results, demonstrates that the proof so far remains as inconclusive and non-valid as ever. This maintains honey bees at the state of ordinary insects, which may be somewhat disappointing. But then, it also retains our old fashioned phylogenetic system in a relatively intact state, which is no small consolation. REFERENCES AZ, J. W. (1970). In Development and Evolution of Behavior: Essays in Memory of’ T. C. Shneirla (L. R. Aronson, E. Tobach, D. S. Lehrman & J. S. Rosenblatt, eds) pp. 53-74. San Francisco : Freeman. DAWKINS, R. (1969). Science, 165, 751. ESCH, H. & BASTIAN, J. A. (1970). 2. Vgl. Physiul. 68, 175. FREE, J. B. (1969). Nature 222, 778. FREE, J. B. (1970). Behaviour 37, 269. VON FRISCH, K. (1946). Osterr. ZooI. 1, 1. Translated, 1947: Bull. Anim. Behav. 5, 1. VON FRISCH, K. (1948). Naturwiss. 35, 1,35,38. Translated, 1951: Bull. Anim. Behav. 9, 2. VON FRISCH, K. (1949). Experientia 5, 142. Translated, 1951: Bull. Anim. Behav. 9, 26. VON FRISCH, K. (1950). Bees: their Vision, Chemical Senses, and Language. Ithaca, New York: Cornell. VON FRISCH, K. (1951). Naturwiss. 38, 105. Translated, 1952: Bee World 33, 19. VON FRISCH, K. (1962). Sci. Am. August 207, 78. VON FRISCH, K. (1967a). The Dance Language and Orientation ofBees. Cambridge, Mass. : Harvard. VON FRLWH, K. (19676). Science 158,1072. VON FRIXH, K. (1968). Anim. Behav. 16, 531. VON FRISCH, K. (1973). Anim. Behdv. 21, 628. VON FRIXH, K. (1974). Science 184. 663. FRIPSEN, L. J. (1973). Biol. Bull. 144, 107. GONCALVES, L. S. (1969). J. apic, Res. 8, 113. GOULD, J. L. (1974). Nature 252,300. GOULD, J. L. (1975). Science 189,685.
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GOULD, J. L., HENEREY, M. & MACLEOD, M. C. (1970). Science 169,544. JOHNSON, D. L. (1967). Science 155,844. JOHNSON, D. L. & WENNER, A. M. (1970). .I. apic. Res. 9, 13. KREBS, J. R. (1975). Nature 258, 109. LEHRMAN, D. S. (1970). In Development and Evolution of Behavior, pp. 1 J-52. Ibid. LINDAUER, M. (1961). Communication among Social Bees. Cambridge, Mass. : Harvard. LINDAUER, M. (1971). Am. Nat. 105, 89. MAIER, N. R. F. & SCHNEIRLA, T. C. (1935). Principles of Animal Psychology. New York: McGraw-Hill. MAIER, N. R. F. & SCHNEIRLA, T. C. (1964). Principles of Animal Psychology. New York: Dover. MAUTZ, D. (1971). Z. Vgl. Physiol. 72,197. PIEL, G. (1970). In Development and Evohrtion of Behavior, pp. 1-13. Ibid. ROSIN, R. (1975). Science 188, 174. TAVOLGA, W. N. (1969). Principles of Animal Behavior. New York: Harper & Row. TAVOLGA, W. N. (1970). In Development and Evolution of Behavior, pp. 281-302. Ibid. WELLS, P. H. & WENNER, A. M. (1971). Physiof. Zoof. 44, 191. WELLS, P. H. & WENNER, A. M. (1973). Nature 241, 171. WENNER, A. M. (1967). Science 155, 847. WENNER, A. M. (1968). In Animal Communication (T. Sebeok, ed.), pp. 217-243. Bloomington, Indiana: Indiana University. WENNER, A. M. (1970). In McGrau?-Hill Yearbook of Science and Technology, pp. 110-113. New York: McGraw-Hill. WENNER, A. M. (1971). The Bee Language Controversy: An Experience in Science. Boulder, Colorado : Educational Programs Improvement Corporation. WENNER, A. M. (1974). In Nonverbal Commlmication (L. Krames, P. Pliner & T. Alloway, eds), pp. 133-169. New York, London: Plenum. WENNER, A. M., FRIESEN, L. J. & WELLS, P. H. (1972). Sci. Am. 227 no. 6, 6. WENNER, A. M. & JOHNSON, D. L. (1967). Science 158, 1076. WENNER, A. M., WELLS, P. H. & JOHNSON, D. L. (1969). Science 164,84. WENNER, A. M., WELLS, P. H. & ROHLF, F. J. (1967). Ph.ysiof. Zoo/. 40, 317. WILSON, E. 0. (1972). Sri. Am. 227 no. 6, 6.
Note added in proqj’
Two more publications on the issuehave come to my attention: GOULD, L. (1975). J. camp. Physiol. 104, 161, and GOULD, J. L. (1976). Q. rev. Biol. 51, 211. The first of these reports on additional “Direction experiments”, including “Wenner controls”, and is subject to the same type of criticism presented in this paper. The second publication claims that the author’s interpretation of his experimental results is conclusively proven, becauseno alternative explanation based on odor alone is presumably possible. The publication also, prematurely, views the controversy as already closed in favor of the “dance language” hypothesis. However, the possibility of an alternative explanation based on odor alone has never been properly investigated. (A proper investigation would have required investigating the effects of a whole variety of possible factors on use of odor alone.) The possibility that no other explanaJ.
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tion except one based on odor alone might be acceptable has never been properly tested either. (The test requires including the proper controls.) At the same time, the author’s interpretation is unacceptable on its own merit. It cannot account for results that are incompatible with it; it cannot explain why under “stress”, which presumably elicits use of “language”, some bees still use odor alone; and it cannot explain why users of odor alone who can arrive at all stations (including stations of the array), are barred from the array under “stress”.
