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Lankester defines "Bionomics.--The lore of the farmer, gardener, sportsman, fancier, and field naturalist, including thremmatology, or the science of breeding, and the allied teleology, or science of organic adaptations: exemplified by the patriarch Jacob, the poet Vergil, Sprengel, Kirby and Spence, Wallace, and Darwin.... Buffon alone among the greater writers of the three past centuries emphasized that view of living things which we call 'bionomics.' Buffon deliberately opposed himself to the mere exposition of the structural resemblances and differences of animals, and, disregarding classification, devoted his treatise on natural history to a consideration of the habits of animals and their adaptations to their surroundings, whilst a special volume was devoted by him to the subject of reproduction.... Buffon is the only prominent writer who can be accorded historic rank in this study."

As I have access to but few of Buffon's writings, I quote the above. Bionomics is seen not to be synonymous with ecology, as defined by most students, although it includes much that is ecological. The chaotic and unorganized "lore of the farmer" has no unifying or guiding principles, and although it contains many facts, from which a science may be built, to call it science seems undesirable.

It is of course advantageous in some ways to have agreement as to the limitations of ecology, or any science, but even the more exact sciences seem to fare little better, as is shown by the following statement: "It is not long since I heard a university professor begin a lecture on physics somewhat in this way: 'Physics is the science of matter and energy. This field is so large that it is customary at present to break off the physics of the molecule and its reactions and call it chemistry. Also to put to one side the physics of the heavenly bodies and call this a part of astronomy,' etc."

FORBES, S. A.

In this paper Forbes defines ecology and points out, I believe for the first time, that economic entomology is simply applied ecology. He says, "The study of oecology is thus to the economic entomologist what the study of physiology is to the physician."

Especially pp. 28-32 on the relation of ecology to economic entomology.

HERDMANN, W. A.

EMERY, C.

CLEMENTS, F. E.

Research Methods in Ecology, pp. 334. Lincoln, Nebraska.

ADAMS, CHAS. C.

The standpoint of this paper is very much in harmony with that advanced in this book.

CASE, E. C.

WHEELER, W. M.

FLAHAULT, C., and SCHR?TER, C.

WHITE, C. A.

This paper and the two following references illustrate the intimate relation of ecology to phases of geology.

GRABAU, A. W.

WALTHER, J.

Shows the close relation between ecology and geology. The process standpoint is emphasized and the past is interpreted in terms of processes now in operation.

ADAMS, CHAS. C.

As a record of the associations, their interrelations and responses to their environment--before they have become too much changed or exterminated. This is a duty to future naturalists and to future science. The animal remains in themselves are only a very incomplete record; their activities and environments are an essential part of the animals and should also be preserved.

At the present time it is very difficult to secure trained men to do ecological surveying. Even a superficial examination of this paper should show that familiarity with ecologic methods and results is not one to be acquired offhand, but a knowledge which requires considerable special training; not only as much as is usually required for other kinds of zo?logical work, but generally more, because of its synthetic relational tendency which requires a broad knowledge as well as some special knowledge in several lines of biology and the allied sciences. Conventionally considered, a properly equipped physiologist must have a working knowledge of certain phases of modern physics and chemistry in addition to his grounding in biology. A properly trained anatomist should have a knowledge of physiological and developmental processes, or his anatomy is purely descriptive and static. A student of general zo?logy should be grounded not only in physiological and developmental processes, but also in the relations of the organisms to their complete environment. The ecologist requires also the grounding in physiological, developmental, and ecological processes of adjustment, but as well he must understand the processes by which the vegetation and the physical environment have been and are being developed and their method of mutual interrelations and adjustment. It is difficult for some students to develop the ecological phases in the field. There are many disadvantages to be overcome. The difficulties are similar, in some respects, to those of the ethnologist who is sent on some museum expedition. The wealthy donor of the funds may wish to see a room filled with specimens on the return of the ethnologist, so that materials which have bulk and make a showing take precedence over detailed studies of the habits, traditions, languages, and descriptions of the people, because such studies require appreciation rather than inspection for evaluation. The zo?logical student may meet with just the same kind of difficulty. His institutional authorities often judge values by the cubic foot and pound, rather than by the quality of relations discovered. The student himself who has had an extensive collecting experience, in which quantity and variety have been the ideal, finds it difficult to return from a day's work with only a few pages of notes on the responses of the animals, and with perhaps only a few specimens.

If natural preserves are not made, how will the next generation be best grounded in the general principles of the science? Are these complex modified conditions the natural place to start the student, or should such problems be reserved for the maturely trained one? These disturbed fragmentary conditions may be likened to fragmentary fossils whose interpretation is attempted. A paleontologist whose only knowledge of animals was derived from such fragments, and who had never known a perfect living animal, would certainly be at a great disadvantage in such an investigation. The natural starting point therefore seems to be in as nearly natural normal environments and associations as is possible, and with such experience one is prepared for the more complex problems resulting from man's activity.

"Is not the biological laboratory which leaves out the ocean and the mountains and meadows a monstrous absurdity? Was not the greatest scientific generalization of your times reached independently by two men who were eminent in their familiarity with living things in their homes?"--BROOKS, 1899, p. 41.

In taking up field work, or any other kind of complex study, a definite working plan is of much value. For this reason this subject deserves more than a mere mention. Such a plan greatly aids in keeping in mind the general aim of the study, and particularly the lesser aims which develop with the analysis of the subject. It further aids in the proper orientation and subordination of allied subjects which crowd in from all directions.

For many students it is a good plan to make out a general outline of any proposed study as soon as possible after the work has been started. In the beginning it is difficult to realize the radiating relations of a subject, and the attempt at such plans aids in the perception of these relationships and becomes an important guide. Such an outline will need several revisions, but these changes will come with a broadening and deepening grasp of the subject. Perhaps the greatest value of such a plan is that it facilitates the conscious effort to seek a definite goal by maintaining a standard of measurement.

In addition to a comprehensive analytical plan others are useful. Particularly is this true when several lines of work are being done simultaneously or when the work must be interrupted frequently. Under such circumstances even a daily program may aid in utilizing many of the fragments of time which are so easily lost. In this way incomplete observations, verifications, and similar small items which are time-consuming may be made. These plans apply with particular force to field study when several lines of observation are being driven abreast. I have found it profitable to keep memoranda on note slips which will recall items needing further attention, at certain places in the field or on certain subjects. Thus, for example, if plans are suddenly changed and another locality is visited, the proper note slips indicating the points for special study at such a place are quickly secured, and one can hasten to the field prepared for the work of the day. Of course, similar plans are applicable to many kinds of work.

To learn how to study in the field, and not simply to collect, is one of the most important habits which a field naturalist and the ecologist has to acquire. This is one which he must, to a large degree, master alone, without the ready access to assistance, as is usually the case in the laboratory study. It is also a subject about which it is difficult to give useful suggestions, other than those of the most general nature. Directions for collecting are, on the other hand, simpler and more accessible in the form of numerous manuals filled with practical suggestions.

Field study is not confined to observations alone, but to the securing of all kinds of evidence from the field which will aid in the interpretation of the field relations of animals. Thorough intimacy with the animals can only be acquired through repeated and prolonged excursions in the field. This may mean excursions at any hour of the day or night. Part of this familiarity is best acquired by an intensive study of some limited area or association, and by thus establishing a unit for comparison so that the differences in other places are more readily perceived and described.

Before selecting a limited area for study one should make a general examination of a much larger tract, so that one may be sure that the area selected is a fair sample and worthy of the special study. There are also many advantages in selecting areas little modified by man. Such modified areas may, to better advantage, be considered later; just as pathology should be studied after one is grounded in normal histology. Undoubtedly the normal, or its approximation, is the best foundation upon which to build, and here we have the educational argument for natural preserves for animals and their superiority over highly modified "parks" for the same purpose.

Having selected a locality, repeated and prolonged visits, careful observation, and description of the place and animals will enable one to acquire the desired familiarity. For the study of the behavior of the animals concerned many observations can be made by remaining quiet, carefully concealed, and recording all observations. This method is particularly applicable to animals which live in exposed places, such as many insects, birds, and mammals. For other kinds, only indirect methods of observation are possible, or only when under controlled conditions. For the indirect methods of observation many forms of traps have been devised, traps not intended merely to receive the dead animal, but those also which will secure the animal and reveal something of its behavior. For the study of the habits and behavior of such animals as live in the soil or under bark, etc., both extensive collecting and examination of the animals in vivaria will also be necessary.

Fortunately for the student of mammals, birds, and fishes we have excellent guides for the technique of study and photographing of individual and associated kinds in the works of Kearton , Chapman , Herrick , and Reighard . It is very desirable that these methods be applied to the interrelations among the animals of an association. The student of behavior in nature has much to learn from many excellent studies of animal behavior which have been carried on in recent years by laboratory students. Fortunately the line between these two methods of study is breaking down to the mutual advantage of each. The border line between these two methods will give excellent returns to any student well prepared in each line of work.

To be sure, it may require more time to study in the field than if one collects specimens only, but it is economical in the long run. There are, of course, certain phases of more indirect observation which can be done best in the study or laboratory, but at present, field study, as contrasted with collecting, is a phase of effort urgently needing emphasis.

Notes are generally taken in one of two forms, in a book or on loose slips of paper or cards . It seems to be very generally agreed that if a book is used it should be of small size, of about 4 x 6 inches, so that it may be conveniently carried in the pocket. For a permanent record such books are a great convenience when once indexed. But when using such notes, while preparing a report, they are not so convenient as the note slips, unless one limits such a report to the form of a narrative. About ten years ago the writer began using a form of notebook in which an aluminum cover held the loose note slips. Thus while in the field one has the advantage of a book with a firm writing surface, and also that of the loose-leaf plan. This form of cover is now used by a number of field naturalists. The disadvantage of the slips not being bound might be remedied in part by using some form of punched slips which are convenient for binding.

Each one must decide for himself which form of recording notes answers his needs most satisfactorily. There are advantages in uniformity, but with the variable nature of work, it is sometimes very convenient to use both methods of recording.

Some students have no method of recording their observations or reflections upon their lines of interest. This seems to be unwise and suggests a method of business without bookkeeping. The efficiency of some students is greater than that of others, not so much because they possess superior mental ability, but because they have superior methods of preserving whatever useful ideas occur to them, while the others, from their lack of records, have no cumulative store upon which to draw. This is an important form of capital. Note keeping is readily seen to consist not only of observations, but also of suggestions, inferences, conclusions, and reflections of any kind which will facilitate methods of work and the interpretation of the facts.

In describing environments, it is desirable to use the same general method for different localities so that the descriptions may be comparable and show some degree of standardization. This method has been found very useful in taxonomic studies and has similar advantages here. A brief general statement of the most conspicuous features may precede, and be followed by detailed descriptions. The order may well vary with individual workers, but a uniform method is desirable throughout any single piece of work and has obvious advantages. Thus one practical plan applied to a forest habitat is, to describe the substratum, the soil, rock, etc., then the forest litter of organic d?bris, then the boles of the trees and the forest crown and its character, and finally the operation of those agencies which are causing changes in the forest and which will perpetuate or change it in the future. No practical forester would be content to shut his eyes to the future crop of wood, and in the study of animal habitats we must not be content to rest below such a commercial standard. To some this seems very theoretical, and yet a farmer who counts upon a crop in five months, or a forester, in fifty years, is not so branded, and the ecologist need have no fear in using such practical methods. In other words, we should consider the future stages of the developing habitat and learn to perceive the evidences which show in which direction development or change is taking place; or to determine the "orderly sequence of external nature." Not only should the future be considered, but we should strive also to read the record backward and interpret the past in terms of processes now in operation. In this respect the point of view of the geologist who interprets the past in terms of present processes may well merit our attention. To understand our habitats they must be studied not only in their length and breadth, but also in depth--past and future--as they have all three dimensions.

The preceding remarks bear equally well upon observations of the activities of animals in nature, on account of the absence of controlled conditions, for these methods have almost as much significance as the study of the environments themselves; and equally careful observations and descriptions are essential, if the detailed processes of animal activities and their transformations are to be recorded.

An experienced naturalist finds that from year to year the amount of notes which he takes increases rapidly, and in a very direct ratio to the progress which he makes in his study. Good note taking is not a passive process, but one which calls for an alert mind. The prolonged interest which is necessary to secure detailed observations implies such a frame of mind. Every one soon tires of any subject unless new features are constantly being discovered.

In the description of the associations in any given habitat, the problem is much simplified if one has a clear idea of dominance, knows how to recognize it, and understands some of its main implications. The dominant forms are the most common and powerful individuals in the association. They may or may not be the most conspicuous, from a superficial view. Conspicuousness may depend upon size, but dominance refers to large absolute numbers and to influence exerted. We may profitably compare an association of animals in a given habitat to a play upon the stage. The environment corresponds to the stage. The dominant members of the association correspond to the leading characters, the secondary species, always present, to the essential but subordinate characters. The individual animals adjust themselves to one another, especially to the dominant forms, and to the environment, as the personalities in the play adjust themselves to the dominant characters, to one another, and to the environment. In both groups some individuals are dominant, some used and useful, some are tolerated, others pick up the crumbs, still others are predatory or parasitic, and all must be mutually adjusted to one another and to the environment.

The number of dominant species within an association is relatively limited, a fact which holds for both plants and animals. A knowledge of perhaps 200 or 300 species of animals will enable one to work advantageously in many localities . Of this number perhaps not more than about one half or one third can be considered dominant. Every one who has tried to make extensive local lists of species knows that it requires many years of collecting to secure a large number of species. These rare species are generally of quite minor importance ecologically. Considerations of this character should be encouraging to those who may be intimidated by the idea of large numbers of species. Then, of course, it should be remembered that there are many aspects of ecological work which do not meet with this variety of animals.

In the eyes of many the determination of specimens is such a formidable task that they are at once repelled from any subject which involves numerous species. But as we have previously remarked, there are phases of ecological study which involve only a minimum amount of such work. On the other hand, one may readily have an undue fear of numerous species, but no one can doubt that the smaller number of species found upon mountains or in the far north gives to a beginner certain advantages for study. But if one's studies are confined to the more restricted habitats, the number of species involved is comparable to the more favored localities mentioned.

An accurately determined series of specimens, conveniently arranged, will be an important aid in one's studies. Two forms of arrangement of such determined series are very helpful; one being synoptic or systematically arranged, and the other ecologically, by associations or by a topical arrangement in harmony with the subjects being investigated. With the use of such series and proper caution, aided by the best keys in the literature, one may hope to make many of his own determinations and thus economize his time.

There are many ways to secure the initial series of determined specimens, and some of these are the following: Our governmental departments, both national and state, and many of our large museums, universities, and academies, have numerous experts who are quite willing and even eager to aid earnest students who wish to have specimens determined. Then, in addition, there are many expert amateurs who are equally liberal, so that when all the sources of aid are considered, the list becomes a surprisingly long one. This is the fact that should be called to mind when considering large numbers of species. A student therefore does not need to work alone, but may have the co?peration of a large number of able and willing collaborators. Naturally we turn for aid to our United States National Museum as one of the first sources of assistance, to the Smithsonian Institution, and to the various scientific departments of the U. S. Department of Agriculture, particularly to the Bureaus of Plant Industry, Biological Survey, and Entomology. These sources alone are able to determine almost any reasonable series of specimens, particularly if they are well preserved. Arrangements for such determinations can probably be made by addressing the proper authorities.

The museums of our larger cities, as the American Museum of Natural History of New York, the Carnegie Museum at Pittsburgh, the Field Museum of Chicago, and many smaller state and local museums are able to give very efficient aid in this line. Other local institutions are the State Universities and Experiment Stations, and the local natural history surveys, which often exist under the guise of a geological or agricultural organization. Frequently they are qualified and willing to do this work.

In very difficult cases it may be necessary to have recourse to Cassell's Naturalist's Universal Directory , in order to find the address of some specialist in a foreign land, who can help, but generally Americans are the best informed upon their own fauna.

Supplementary to, and in some cases a necessary substitute for, a reference series of authentically determined specimens, is one which the student is able to name for himself, by the study of the literature. Without some special training this may become dangerous ground to tread upon, but every now and then some young student begins in this way and develops such care in determining his own collections, that the method cannot be wholly condemned. Such work in itself has fascinations, and one may easily occupy all one's time with it. From the ecological standpoint to stop with determinations only would be like acquiring a certain vocabulary, and stopping before learning how to use the language. Ecological work aims to use the names of species as the most concise method of referring to kinds of animals whose interrelations are to be described and interpreted. Taxonomy is the tool.

CHAMBERLIN, T. C.

Very important papers and worthy of careful study.

GILBERT, G. K.

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