«PREVIOUSLY PUBLISHED»

ONCE AGAIN ON DEVELOPMENTAL STABILITY
[Edited]

We completely agree with M.Kozlov as to the seeming simplicity of the method of assessment of fluctuating asymmetry (FA), proposed by V.M. Zakharov’s team, but no more than that. The illusion of simplicity, whose victim M.Kozlov has become, is conditioned by the fact that the authors of the manual he criticizes were not aiming to equip reserve staff with a method for the exposure and substantiation of fluctuation features. The main objective of the manual is more modest: to teach the skills needed to apply this new method. Prior to this, V.M. Zakharov’s group had been involved for years in painstaking scientific work, reflected and summarized in numerous articles and monographs, well-known to Russian and foreign researchers alike.

I agree with M. Kozlov that the methodology of developmental stability (not of “sustainable development” — p. 24) is far from complete. However, the way he manipulates the reader by citing the garish titles of some articles (e.g “Waltzing with Asymmetry” by A. Palmer) is hardly appropriate. By the way, Palmer himself, an acknowledged FA apologist, discusses 18 algorithms of FA assessment in his work (Palmer, Strobeck, 2001), yet he has never labeled the method anathema. The need to improve methods of FA quantities assessment was the topic of animated discussions at the 3^rd International Conference The Health of the Environment (May 22—23, 2001, Moscow). There we presented our proposals – the complete version was published in the Works of Kerzhensky State Nature Reserve (Gelashvili et al, 2001). A. Palmer and other experts read papers at the conference.

But where one cannot agree with M. Kozlov is in his choice of arguments which amount to eclecticism and juggling with facts.

1. Concerning mistakes in measurement. The algorithm of standard procedure of FA assessment of a feature under study always begins with a compulsory check of any statistically significant difference from zero average (a test on non-orientation and fortuity of fluctuations). This stage is necessary when we choose, substantiate and verify fluctuating features. The features listed in the methodological manual by V.M. Zakharov and his colleagues were features that had been tested at this stage in previous works! By the way, M. Kozlov’s expression “ideally symmetrical organism” belongs to informational noise since in the real world ideal symmetry does not exist! (Veil, 1968).

2. Bewildering is the phrase: “superimposed on the leaf reduction if we draw nearer to the enterprise” (p. 24). I cannot help but regret that M. Kozlov did not take into account the scaling effect of linear dimensions, which is obligatory when using plastic features. Incidentally, we proposed taking this effect into account for segmented features as well.

3. Still more bewildering is the phrase: “if the features under analysis have been correlated”. Of course it is impossible to use correlated features or their asymmetry to assess FA. But what does this have to do with the authors of the manual, who recommend using uncorrelated features of birch tree leaf plate? As for “bundling of information”, the procedure of summing up (linear) — is one of the most widespread approaches in indexology. We have proposed (Gelashvili et al, 2001b) a new mathematical procedure, which allows one to evaluate the FA with any degree of accuracy. The method was taken from crystallography and is based on using the so-called bundling.

4. We cannot understand what is bad about Student’s t-criterion, which can and should be applied in conjugate comparisons (irrespective of geography, both in the West and in the East). In case of numerous comparisons, Bonferroni’s correction method is recommended. As for dispersion analysis, theoretical analysis and our experience in the study of the FA of social insects (Radaev, 2001) provide evidence of the efficiency of multidimensional disperse analyses (MANOVA).

Thus, M. Kozlov seems to have shared his own mistakes in the study of FA with the reader. Well, this experience is very instructive.

Finally, it is my pleasure to quote M. Kozlov: “I consider this direction to be very promising, but only if the basic information is collected with great accuracy and the results are scrupulously analyzed” (p. 25). It is hard not to agree with this conclusion.

Literature

D.B. Gelashvili,
Department of Ecology
Nizhny Novgorod University

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