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OCR
24]I. The aim and position of zoocoenology in the system of biological sciences to the methodological procedure that relies only on density relations when defining or analysing a biocoenosis. Ihey oppose Beklemishev (1931), who wrote that a biocoenosis is more than the sum of its species, and displays phenomena that cannot be explained solely by the autecology of the constituent species. These authors instead declare that any problem of biocoenology can only be approached through autecological methods; consequently, we carry out autecological research even when we study the phenomena displayed by communities. We can only partially agree with this viewpoint. We also emphasise that biocoenology cannot be studied without autecological knowledge about the constituent populations, and that the questions “what lives together” and “in what proportions” are not the defining, major questions of biocoenology instead, these are the “why are they together” and “how do they coexist” enquiries. However, if we accept the objective existence of biocoenoses, the branch of science that studies the regularities of this unit as a unit of coexistence, is more suitably called biocoenology than autecology; in short, there should exist a branch of science that views the environment not from the viewpoint of individual species, but through analyses of a whole community as a unit. It is true that during biocoenological research, we reveal several fragments of autecological information; among them, knowledge that is related to phenomena that could not have been manifested without the existence of the coenosis. This is the reason why we cannot fully reject Beklemishev’s viewpoint, because certain autecological knowledge can only be obtained if the studied population becomes a member of a community containing another population(s). Using an example to illustrate this phenomenon that is a property of autecology but manifests itself on the plane of biocoenology, the following picture can be presented. When, on a strongly aphid-infested tree, there is high ant activity, this can greatly disturb the activities of populations of aphid-feeding species. The ants only disturb them because the aphid feeders are associated with the aphids, and these aphidfeeding populations clash with ants on a common energy source. It is evident that this activity is a manifestation of ant autecology, which exists only because of the association with these other species. The same ants are, probably, totally indifferent to the same species on parts of the tree that are not aphid-infested or, if the aphid feeders are prey for the ants, ant predation on them will have less impact on aphid density (and the zoocoenosis formed), than when they form a coenosis around high-density aphid patches. When the ants are missing from the tree, a qualitatively and quantitatively different coenosis will be formed, and the preceding phenomenon will not appear. How a given species behaves in its environment, and how this environment influences the species, are questions of autecology. But the question of why different populations of this same species behave differently can only be answered by the prevailing conditions of the specific environment where this population occurs. If there are populations of other living species coexisting under these conditions, the
