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    Observations on the Status of Ecology

    Author(s): Richard S. MillerSource: Ecology, Vol. 38, No. 2 (Apr., 1957), pp. 353-354Published by: Ecological Society of AmericaStable URL: http://www.jstor.org/stable/1931696 .

    Accessed: 28/03/2011 00:26

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  • 7/27/2019 1957 Miller.pdf



    The status of ecology with respect to its related fieldsand the biological sciences generally has been deplored bya number of ecologists for its lack of maturity and defini-tion (Birch 1955; McMillan 1954, 1956; Park 1945).The essential objectives of ecology as a field of studyand as a definitive science are rather poorly defined and,due to its broad interests and to the popularity of itsconcepts in related fields, it is often difficult to separatepurely ecological research, directed toward the solutionof fundamental problems in ecology, from that whichhas "ecological aspects." While we may correctly referto ecology as "the study of the relations between anorganism and its environment," this definition is toobroad to clarify the scope of ecological research and itdoes not define the position of ecology with respect tothe other biological sciences. Since an organism doesnot, and cannot, function outside an environmental con-text of some sort, we might easily infer from the abovedefinition that all biological research is ecology. Tosome authors this seems to be the case, but unless ecologyhas certain characteristics which can be described ob-jectively and which distinguish it from its related fields,there is no justification for maintaining that it is anythingmore than a useful but rather vague point of view.While it is perhaps true in a sense that the essence ofecology does lie in its point of view, as Woodbury (1954)asserts, and that ecology is applicable in this form to awide variety of biological problems, a statement of thissort merely signifies an awareness of the fact that plantsand animals have environmental relations which governthe expression of their various attributes. As such, anecological point of view may be a valuable research toolor method of interpretation, but it is not a qualified state-ment of the aims, the methods, or the scope of ecology.We expect for example that every modern biologist acceptsthe facts of evolution and that he uses an evolutionaryinterpretation whenever it is appropriate, but we usuallyreserve the term "evolutionist" for a comparatively smallgroup of scientists who devote their research and thinkingto the major problems of evolution, and who have madefundamental contribtuions to evolutionary theory. In otherwords, the mere acceptance of the fact of ecologicalrelations or the use of an "ecological approach" need notimply research on the fundamental problems of thescience of ecology, nor does it justify the label "ecolo-gist," and in order to describe ecology as a definitive sci-ence we must, in some way, be able to describe a set ofaims and concepts which are unique.Dice (1955) contends that ecology has no naturalboundaries and that any attempt to draw boundaries be-tween ecology and its related fields would "do more harmthan good." This assumption depends upon whethersuch boundaries are used to define the areas of researchwhich ecologists are particularly concerned with orwhether, instead, they place restrictions on the interpre-tation of ecological events and concepts. These alterna-tives are not inseparable and the latter is obviously asundesirable in ecology as it is in any field. But in spiteof the above contention, Dice (1955) attempts. to defineecology by its methods, its vocabulary, and the followinglist of concepts: levels of organization, energy relations,ecosystems, ecologic balance, reproduction, competition,variability, ecologic patterns, individual adaptability, evo-

    lution, and social cooperation. While he does not claimthat "these or other concepts are exclusively the prop-erty of ecology as opposed to other sciences," certain ofthem, because they are not unique, cannot be regarded asdefinitive. Certainly concepts of reproduction, individauladaptability, and evolution are just as appropriate, if notmore so, to fields other than ecology. Dice is undoubtedlycorrect when he implies that concepts cannot be regardedas "exclusively the property" of any particular field,and this is perhaps even more true of experimentalmethods and techniques; but we may on the other handindicate those concepts or methods which are especiallyapplicable to research in a particular field, or which areprimarily its concern. For example, McMillan (1956)argues that "Techniques such as the quadrat (cited byDice, 1955, as definitive of ecology) and the bisect, whichare used for dealing with spatial arrangements are ge-ographical, not ecological tools." Obviously it is ratherpointless to insist that spatial arrangements are theexclusive concern of geographers, since spatial arrange-ments are considered in virtually every field of science,even though they may involve different subjects or differ-ent levels of organization. In other words, it is not somuch the quadrat method which is unique in this case,but rather the particular problems to which it is applied.While ecologists use methods and concepts which areoften common to its related fields, their interests tend tocenter on special levels of biological organization; namely,the biological properties of populations and natural com-munities. This fact is expressed in the following observa-tion by Park (1955): "The distinguishing characteristicof ecology is its ultimate preoccupation, not with theindividual organism, but with the environmental relationsof groups. Thus the group, or population, emerges asa natural entity." In another paper Park states, "Thesubject matter of ecology can be considered under fourcategories, each of which represents a grade of biologicalorganization of increasing functional and structural com-plexity. These four are: the individual organism, thesingle species population, the mixed or several speciespopulation and the community" (Park 1948). These cate-gories are included in the following diagram of the differ-ent units or levels of biological organization:

    CellsOrgans and tissues

    IndividualsSingle speciespopulations

    Mixed species Subspeciespopulations/\Communities SpeciesIn this diagram, subspecies and species, which we mayregard as "taxonomic populations," are considered dis-tinct from the "biological population" of the ecologist.While this is to some extent an artificial separation, the

  • 7/27/2019 1957 Miller.pdf


    354 NOTES AND COMMENT Ecology, Vol. 38, No.2systematist is usually concerned with statistical measuresof variation in geographical units, whereas the ecologistdeals with the biological properties, such as age struc-ture, population growth, and population density, of localunits which can usually be censused.At each of these levels of complexity there are fieldsof study devoted to the structural or functional propertiesassociated with that particular grade of organization. Aseries of examples is offered in the following tabulationof some of the principal subdivisions of biology and thelevels of organization with which they are primarily con-cerned:

    ORGANIZATION STRUCTURE FUNCTIONCells Cytology CytologyOrgans and tissues Histology PhysiologyIndividuals Anatomy PhysiologySingle-species Ecology Ecologypopulations Systematics GeneticsMixed-species Ecology Ecologypopulations ParasitologyCommunities Ecology EcologyGeographySubspecies Systematics GeneticsSpecies Systematics GeneticsGeography

    One must recognize, of course, that related fields arebound to have overlapping interests and that their re-search will often be directed toward similar, if not identi-cal, problems; but this does not preclude their beingseparable on the basis of their primary concerns. It hasoften been pointed out that "ecology uses methods bor-rowed from physiology (c.f. McMillan 1954), and someauthors have in fact described ecology as "field physi-ology"; but the ecologist begins with the individual ashis smallest unit of study and is primarily interested inthe biological properties of populations and communities,whereas the physiologist is concerned more with indi-viduals than with populations, even though he may studythe effects of environment in certain situations. Ecologyand genetics, on the other hand, are both concerned withthe same level of biological organization in many cases,as with population genetics and population ecology; butthe genetiticist is only secondarily interested in the unitresponses of populations to environmental factors, exceptin so far as the hereditary mechanism is involved (Odum1953).The above scheme gives little prominence to thetraditional division between autecology and synecology,since it is felt that ecology is invariably concerned withgroup phenomena and ecological research is seldom, ifever, restricted to an autecological subject. The centraltheme of ecology is a list of concepts pertaining to groupphenomena, most of which may be approached through

    the study of single-species populations, mixed-species pop-ulations, or- communities. Furthermore, these concepts,such as food chains, the pyramid of numbers, competition,predator-prey relations, parasite-host relations, populationgrowth, energy relations, and the natural regulation ofnumbers, each have -structural and functional character-istics which tend to comprise one of the natural divisionsof ecological study, and each lends itself to both descrip-tive and experimental study. Ecology has been ratherstrongly criticized for its emphasis on descriptive study(McMillan 1954), but surely its ultimate aim is a syn-thesis that will describe "not only the parts of a complexsystem but the interaction and balance between them,and the dynamic properties of the system as a whole"(Elton and Miller 1955). Community ecology has beenparticularly slow to progress from the study of structureto that of function and to enter an experimental phaseof research, but the subject matter of community ecologyis extremely complex and a vast amount of informationfrom single- and mixed-species population relations isnecessary before adequate synthesis at the communitylevel is possible. If, however, our central aims are re-search on group phenomena such as those listed above,we may expect that the field of ecology will progressfrom description to -experiment as measurements are sub-stituted for generalized observations (Allen 1955), andthat it will retain its specific identity through its concernwith population and community relations. It is onlywithin these areas of research that ecology can find abasis for a definitive status in the biological sciences.

    REFERENCESAllen, K. R. 1955. The growth of accuracy in ecology.Proc. N. Z. Ecol. Soc., 1: 1-7.Birch, L. C. 1955. A review of "Elements of Ecology"by G. L. Clarke. Ecology, 36: 369.Dice, L. R. 1955. What is ecology? *Sci. Monthly,80: 346-351.Elton, C., and R. S. Miller. 1954. The ecological sur-vey of animal communities: with a practical systemfor classifying habitats by structural characters.Jour. Ecol., 42: 460-496.McMillan, C. 1954. Parallelisms between plant ecologyand plant geography. Ecology, 35: 92-94.

    . 1956. The status of plant ecology and plantgeography. Ecology, 37: 600-602.Odum, E. P. 1953. Fundamentals of ecology. Phila-delphia: Saunders.Park, 0. 1945. Observations concerning the future ofecology. Ecology, 26: 1-9.Park, T. 1948. Population ecology. Encyclopedia.Brittanica.

    1955. Ecological experimentation with ani-mal populations. Sci. Monthly, 81: 271-275.Woodbury, A. M. 1954. Principles of general ecology.New York: Blakiston.