Guide to the study of animal ecology

by Charles C. Adams

“The actual method of work is to first watch the organism under its natural environment, until one finds out all things it does. Then the environment is changed a little, to see what difference this makes in the behavior. We thus try all sorts of different ways of getting the animal to change its behavior,—including the application of definite chemical and physical reagents of most varied character.... We thus try to find the organism’s system of behavior and the things that influence it,—becoming acquainted with the creature as we might get acquainted with a person with whom we are thrown much in contact.”—H. S. Jennings (1910).

“My object being the study of the correlative instincts of the young and adult in relation to all that could be learned about them in a natural environment, I have followed my usual custom of going out to the birds, instead of taking them into the laboratory. The facts which the laboratory can be made to yield are invaluable, but they belong to a different class from those for which we are now mainly in search, behavior under the usual or normal conditions.”—F. H. Herrick (1910).

“As will be seen, these studies include both field and laboratory work, especially of the American species, and I have made the field work emphatic wherever at all practicable. I have elsewhere (1909, p. 157) [Jour. Exp. Zoöl., Vol. VII] emphasized the crying need for larger attention to this phase of experimental work, believing that in many cases it is all but impossible to secure trustworthy results as to behavior of animals where the work has been done under such unusual, unnatural and artificial conditions as most laboratory provisions afford. What right has one to assume that the actions of an animal taken rudely from its natural habitat and as rudely imprisoned in some improvised cage are in any scientific sense an expression of its normal behavior, either physical or psychical? Is it within the range of the calculus of probability that conclusions drawn from observations made upon an animal in the shallow confines of a finger-bowl, but whose habitat has been the open sea, are wholly trustworthy? It is no part of my purpose to discredit the laboratory or laboratory appliances as related to such investigations. They are indispensable. But at the same time let it be recognized that they are at best but artificial make-shifts whose values, unless checked up by constant appeal to nature, must be taken at something of discount.... It seems to the writer that until one has been able to place his specimens under conditions approximating the natural, or has at least brought them to a state of semi-domestication, where in food-taking, evidence of health, etc., they are at ease, he has small right to dogmatize as to conclusions, or presume to make such conclusions the basis of so-called laws of behavior. Not a little of recent investigation along the lines of behavior has been vitiated at just this point, and must be repeated to be made trustworthy. The amazing mass of contradictory results which has loaded the literature of recent years is attributable to some extent to this misfortune.”—C. W. Hargitt (1912).

“We are apt to contrast the extremes of instinct and intelligence, to emphasize the blindness and inflexibility of the one and the consciousness and freedom of the other. It is like contrasting the extremes of light and dark and forgetting all the transitional degrees of twilight.... Instinct is blind; so is the highest human wisdom blind. The distinction is one of degree. There is no absolute blindness on the one side, and no absolute wisdom on the other.”—C. O. Whitman (1899).

The precedence here given to changes in behavior is in harmony with the emphasis which is put upon processes and genetic phases or sequences throughout this book. As Holmes (1905, p. 108) has well pointed out, behavior consists of relatively fixed and relatively changeable responses, with intergradations. There are thus two avenues of approach which he sums up as follows (p. 112): “In the trial and error method the random character of the movement impresses us most; in the tropisms, the element of direct determination by the environment. Both of these factors run through the behavior of all animals, but they are mingled in various proportions in different forms. In the lives of most, if not all animals both are essential elements in the adjustment of the organism to its conditions of existence.” And in regard to those responses which do not change in form with experience, he says (p. 106): “The element of spontaneous undirected activity is one of vast if not essential importance in the life of nearly all animals. The simpler animals profit by their varied experience, although they may not learn, and thus secure some of the advantages which it is generally considered the special function of intelligence to confer.” Thus to the ecologist studying the sequences of changes in the environment, and changes in the organism, it is but natural and consistent for him to apply the same methods to behavior, in order to facilitate their mutual relations and aid in their interpretation. In a study of the environment we also have the relatively stable elements and the relatively rapidly changing ones, and any adequate understanding of animals must correlate these four variables: two relatively changing, one in the organism and one in the environment; and two others relatively stable, one in the organism and the other in the environment.

Jennings, H. S.

1905. The Method of Regulation in Behavior and in Other Fields. Jour. Exp. Zoöl., Vol. II, pp. 473-494.

Holmes, S. J.

1905. The Selection of Random Movements as a Factor in Phototaxis. Jour. Comp. Neurol. and Psychol., Vol. XV, pp. 98-112.

Jennings, H. S.