Seite 47 [47]
§ The structural elements of a zoocoenosis | 45
§ THE STRUCTURAL ELEMENTS OF A ZOOCOENOSIS
Therefore, amongst these groups, what are the structural elements of a
zoocoenosis?
Given that the most important task for every animal is to secure the energy
necessary for its life functions, the sought-for structural elements can only
be feeding-based life forms that are essential to build a zoocoenosis.
There are multiple classifications of life forms, and animal ecologists have,
so far, been unable to reach an accepted order. Consequently, the life form
that we will follow needs a clear and unequivocal definition. This definition
refers to a trophic-based assessment from a coenological viewpoint, and can
be phrased as follows: a life form is any feeding mode (hence, a means of
energy transfer) that is necessary to create a zoocoenosis. It follows from this
that a life form can only be considered a coenologically important trophic
life form if, from the perspective of a zoocoenosis, the given life form is
essential. What are these essential life forms?
Such life forms can only be higher-level categories, such as corrumpent
elements whose feeding activities liberate the plant-bound energy; the way
in which this happens is irrelevant, the emphasis is on the end result.
Examining the seven groups from this point of view, we can conclude the
following. Above all else, the corrumpent elements, directly linked to the
primary energy sources, are necessary for an animal association to form,
because they are the initial transmitters of the energy flow into the animal
realm. The continued existence of the plant cover, assuring the survival of
the corrumpent elements, depends, in many respects, on animal activity,
thus we must recognise that sustinents are also necessary structural elements.
Obstants can only exist ina community if at least one of the previous elements
are already present. They bring in a new life form into the zoocoenosis, which
makes them real and essential structural elements. The organic debris
produced by the total biocoenosis contains recoverable energy, allowing
hilophages, forming intercalary elements, to link the others, and they
constitute the fourth structural element of zoocoenoses.
Therefore, the four life forms discussed above, corrumpent, sustinent,
obstant and intercalary semaphoront groups represent the structural elements
of zoocoenoses. These groups, whose necessity cannot be doubted for the
reasons explained above, are separated from the seven groups of animal
assemblages, and are grouped under a discrete term, coetus, meaning the
structural elements of zoocoenoses.
Coeti are trophic-based life form groups that are essential for any
zoocoenosis, and are adapted to exploit certain energy sources (niche, Elton,
1927; life style type, Remane, 1943; sensu lato a collective life form, Balogh,
1953).
Semaphoront groups, rather than species, are members of coeti that are
coenologically equivalent. During its life, the same individuum can belong