108
M A N F R E D D. E N G E L M A N N
VII. PROJECTION
I stated in the introduction that many ecologists feel their science
has come of age. Odum (1964) in particular points to energetics as the
new ecology. If energetics is indeed the new ecology, what guiding principles and predictive models have been developed to guide future inquiry and to aid the energetics ecologist to answer the crucial practical
questions of the day! We must admit that, thus far, the Lindeman model
has been the major guiding principle in energetics. We must also state
that this model has been very little tested and practically unchanged
since its inception over 20 years ago. If it is to be useful, a model for a
community must apply to all situations. Since this paper is primarily
concerned with terrestrial communities, let us consider the information
contributed by the terrestrial ecologists in the light of the Lindeman
model.
First, only three terrestrial communities have been studied thus far
and none has been analyzed completely. Second, none of these studies
was able either to support or refute the Lindeman model, since populations, not trophic levels, were studied. ‘Third, the data in the studies were
all tentative, since the magnitude of the errors involved in the computations cannot be analyzed. The proponents of the Lindeman model are
further hindered by other problems, inherent in the nature of the model:
(1) many animals do not fit into a single trophic level, but by their food
habits, fall into two or more levels; (2) situations of imbalance are common in all communities although they are usually reduced in the climax
community. The model must be modified to take these problems into
account. Ours may be the age of ecology, but it appears that energetics
has not yet come of age.
If the study of energetics is to mature in “its era”, energetics ecologists must make a concerted effort to sample more communities with
the Lindeman model in mind. Research should be aimed at analysis of
food chains and food webs. Such studies would serve not only to document the metabolism of the populations concerned, but also to test
hypotheses concerning energy transfers and biomass ratios between
trophic levels. Only in this way can the true relationship between reality
and the model be found.
It seems to me that the second area ripe for study is delimitation of
communities. To date, no natural area has been investigated to sea
whether energy units can define or locate the boundaries of a community, and to find out whether the energy boundaries, if detectable,
correspond with other observable signs, interpreted as community
boundaries.
Finally, at this point, some relationship is indicated between net
M A N F R E D D. E N G E L M A N N
VII. PROJECTION
I stated in the introduction that many ecologists feel their science
has come of age. Odum (1964) in particular points to energetics as the
new ecology. If energetics is indeed the new ecology, what guiding principles and predictive models have been developed to guide future inquiry and to aid the energetics ecologist to answer the crucial practical
questions of the day! We must admit that, thus far, the Lindeman model
has been the major guiding principle in energetics. We must also state
that this model has been very little tested and practically unchanged
since its inception over 20 years ago. If it is to be useful, a model for a
community must apply to all situations. Since this paper is primarily
concerned with terrestrial communities, let us consider the information
contributed by the terrestrial ecologists in the light of the Lindeman
model.
First, only three terrestrial communities have been studied thus far
and none has been analyzed completely. Second, none of these studies
was able either to support or refute the Lindeman model, since populations, not trophic levels, were studied. ‘Third, the data in the studies were
all tentative, since the magnitude of the errors involved in the computations cannot be analyzed. The proponents of the Lindeman model are
further hindered by other problems, inherent in the nature of the model:
(1) many animals do not fit into a single trophic level, but by their food
habits, fall into two or more levels; (2) situations of imbalance are common in all communities although they are usually reduced in the climax
community. The model must be modified to take these problems into
account. Ours may be the age of ecology, but it appears that energetics
has not yet come of age.
If the study of energetics is to mature in “its era”, energetics ecologists must make a concerted effort to sample more communities with
the Lindeman model in mind. Research should be aimed at analysis of
food chains and food webs. Such studies would serve not only to document the metabolism of the populations concerned, but also to test
hypotheses concerning energy transfers and biomass ratios between
trophic levels. Only in this way can the true relationship between reality
and the model be found.
It seems to me that the second area ripe for study is delimitation of
communities. To date, no natural area has been investigated to sea
whether energy units can define or locate the boundaries of a community, and to find out whether the energy boundaries, if detectable,
correspond with other observable signs, interpreted as community
boundaries.
Finally, at this point, some relationship is indicated between net