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126 IVII. Zoocoenological characteristics the totally different structural framework compared to zoocoenology. Essentially, it is not difficult to realise that this definition of constancy is a relationship to the biotope, and expresses an immutable constraint. Zoocoenology adopted this concept without substantial changes and, also, evaluated itbased on sampling units. Furthermore, a clear indication of this is that constancy in zoocoenology expresses the relationship to the biotope, and its measurement, based on spatial units. It is, though, by no means a structural characteristic because, here, the structure depends on the coeti present, and not on their species identity (more precisely, semaphoront groups), because these are only gualitative features, expressions of gualitative differences among structurally identical coenotic frameworks. One cannot dispute that, for the formation of a zoocoenosis, the quality of the biotope is of fundamental importance; therefore, all zoocoenoses, including their constituent semaphoront groups, relate to the biotope in some manner. Hence, the associations in, for example, poppy vs. oilseed rape, or beech vs. pine forest are substantially different; constancy can only be an expression of these relationships. The expression of constancy by units of sampling (quadrat, sweeps, volume, etc.) is an error, because these units contain fragments of the coexisting zoocoenosis. The constancy, expressed in this way, refers more to the dispersion, the spatial distribution of populations than their connection to a given biotope. If, for example, from 25 quadrats sampled in a plant community, we find semaphoront group representations of a certain species in only 12 quadrats, with abundance in two, this says no more than that the given population is very unevenly distributed; this has nothing to do with either its link to the biotope, or zoocoenosis, and gives no information about the homogeneity of the zoocoenosis, either. The constancy of the given population in the studied biotope is not proven or disproven by its spatial distribution, but is related to its continuous or discontinuous, aspect-linked presence. The concept of constancy, as used in phytocoenology, cannot be appropriated by zoocoenology. Its current use amounts to contradictio in adjectio, because “constancy” measured this way is not constant at all, but changes from hour to hour. It is obvious that we obtain a perception of constancy from our samplings, but constancy cannot have degrees (euconstant, constant, accessory, accidental; Tischler 1950) as a population is either constant or it is not. A given population is constant not because of its occurrence in all the sampled units (although it occurs consistently in all sampling units), but because its relationship to the studied biotope (oecus) holds constant for the duration of an aspect, thus it can repeatedly be found there. The constancy of a population cannot depend on its density. Constancy does not depend on abundance, or regular or irregular distribution, but merely on the occurrence itself. This presence assumes the existence of life conditions that the given population will find all the time, or during a certain period, in a biotope (oecus). If, for example,
