PATTERN AND PROCESS IN COMPETITION
7
are its component elements? What constitutes a common resource or
ecological requirement that can legitimately be considered the object
of the competitive process? Is competition limited to interactions between individuals and species at the same trophic level, or is any
interaction which has a deleterious effect on the existence or increase
potential of another individual or species a form of competition? How
can the action of competition be detected and evaluated in natural
situations, and what constitutes adequate proof of competition?
A. THE PROCESS O F COMPETITION
Because most of our knowledge of competition has come from
laboratory studies designed to test the outcome of a competitive interaction, there has been a tendency to ignore the fact and nature of the
process and to view competition almost entirely in terms of its end
result of selective elimination. It is perfectly legitimate to design an
experiment in which competition is defined as the elimination of one
species by another, as in Park’s atudies of competition in Tribolium,
but one must also recognize that this design imposes an artificial criterion which is merely a condition of the experiment. Thus, in describing
one such series of experiments, Park (1954) writes, “. . . for the purposes
of this paper only I shall refer to competition merely as those new
events which emerge when two species co-associate and which lead to
the persistence of one species and the elimination of the other.” Park
cautions, however, that this is not advanced as a general definition of
competition, but is merely a sct of ground rules he has selected for a
particular purpose.
Considerable ambiguity and misunderstanding has resulted from
attempts to define the competition process according to its consequences,
and through failure to establish a common resource as the object of
competition. There may be distinct component elements within the
competition process, associated for example with the ecological characteristics of particular taxonomic groups, but these may not be readily
discernible in the outcome of the interaction and their considerable
theoretical significance may therefore be ignored. For this reason,
arbitrary schemes for classifying species interactions in terms of their
positive, negative and neutral effects may be quite misleading. According to Burkholder’s (1952) system of classification, predator-prey and
parasite-host interactions both have f values and may therefore be
classed together. Such a classification ignores their separate ecological
characteristics and requires that we view such interactions entirely as
abstract energy transformations. There may be valid theoretical reasons
for considering the energy flow between all primary and secondary
7
are its component elements? What constitutes a common resource or
ecological requirement that can legitimately be considered the object
of the competitive process? Is competition limited to interactions between individuals and species at the same trophic level, or is any
interaction which has a deleterious effect on the existence or increase
potential of another individual or species a form of competition? How
can the action of competition be detected and evaluated in natural
situations, and what constitutes adequate proof of competition?
A. THE PROCESS O F COMPETITION
Because most of our knowledge of competition has come from
laboratory studies designed to test the outcome of a competitive interaction, there has been a tendency to ignore the fact and nature of the
process and to view competition almost entirely in terms of its end
result of selective elimination. It is perfectly legitimate to design an
experiment in which competition is defined as the elimination of one
species by another, as in Park’s atudies of competition in Tribolium,
but one must also recognize that this design imposes an artificial criterion which is merely a condition of the experiment. Thus, in describing
one such series of experiments, Park (1954) writes, “. . . for the purposes
of this paper only I shall refer to competition merely as those new
events which emerge when two species co-associate and which lead to
the persistence of one species and the elimination of the other.” Park
cautions, however, that this is not advanced as a general definition of
competition, but is merely a sct of ground rules he has selected for a
particular purpose.
Considerable ambiguity and misunderstanding has resulted from
attempts to define the competition process according to its consequences,
and through failure to establish a common resource as the object of
competition. There may be distinct component elements within the
competition process, associated for example with the ecological characteristics of particular taxonomic groups, but these may not be readily
discernible in the outcome of the interaction and their considerable
theoretical significance may therefore be ignored. For this reason,
arbitrary schemes for classifying species interactions in terms of their
positive, negative and neutral effects may be quite misleading. According to Burkholder’s (1952) system of classification, predator-prey and
parasite-host interactions both have f values and may therefore be
classed together. Such a classification ignores their separate ecological
characteristics and requires that we view such interactions entirely as
abstract energy transformations. There may be valid theoretical reasons
for considering the energy flow between all primary and secondary