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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 aphid¬
feeding 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