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OCR
20 | I. The aim and position of zoocoenology in the system of biological sciences forms a real community, and another group whose members are merely cooccurring due to their similar autecological needs. The biocoenosis, though, is not merely an assemblage of individuals that, due to their similar living conditions, occur together, but a higher unit, in which the organisms are bound together (Thienemann, 1939). Therefore, we have to separate the research approach that fulfils its objectives by identifying and counting animals found in a certain plant association, from the other branch of science that, by studying correlations, uncovers the inner relationships (Keve-Kleiner, 1943). The plant cover + its animal “filling” is called a biome (Clements, 1916: “plant matrix with the total number of included animals”). This is not a higher unit of a community, but - similarly to Schimper’s formation - a biogeographical term (Tischler, 1950). Biome and biocoenosis are therefore basic units of two totally different biological disciplines. The biome (for example, a desert, tundra, prairie, alpine meadow, subalpine pines forest, etc.) can be a starting unit of biogeographical studies, but this is not a higher unit above biocoenosis, even though it contains several biocoenoses and, similarly, its animal filling is not a zoocoenosis, even though it is composed of several zoocoenoses. The term biome includes plants and animals; its plant component is a climatically determined formation, and its animal component is the animal assemblage, termed zoon by Tischler. The zoon is thus the animal assemblage present in a certain plant association. In reality, Tischler uses this name for the fauna of a higher unit of biotope, called a bioregion, while the animal component of a biotope is called a zoocoenosis. We cannot adhere to this, because the concept "zoon" does not depend at all on whether, by this, we mean the animal assemblages of a smaller or bigger area. The animals filling an association is a zoon, just as it is of a larger category. The animal assemblage of the two areas, even if of different species composition, is essentially not different because, by definition, they are the same: an unsorted assemblage of animals in a given space. The animal assemblage of a biotope is not the zoocoenosis, but a zoon, as several zoocoenoses can live within one biotope (see Tansley, 1935: “Animal ecologists [... ] constantly find it necessary to speak of different animal communities living in or ona given plant community”; Glen, 1954: “a complex of smaller, interlocking, dynamic systems”). Consequently, the animal inhabitants of a plant association can, collectively, only be called a zoon, and this concept cannot be used for anything else. If we consider the biome as a biogeographical concept, its animal components cannot be anything else but a concept of zoogeography. Indeed, this is what a zoon is and, thus, it cannot be considered a sum of zoocoenoses, as the biome is not a sum of biocoenoses. The biome (plant + animal), zoon (only animals), and climatic formation (only plants) are biogeographical units, while the biocoenosis, phytocoenosis, and zoocoenosis are concepts of communities, and they do not mix.
