rapid" progress when he was introduced to the society of other dogs, and was thus subjected to the influence of canine tradition.

How far this influence extends in animal communities— how far it is either a necessary or even an important contributory factor in the development of certain modes of behaviour is at present in large degree a matter of speculation. And the only justification for speculation in science is that it may open our eyes to modes of influence the range and limits of whose effects may be submitted to the touchstone of careful observation, and, if possible, experiment. In this instance it is rather the indefiniteness of the evidence before us than its absence that stands in the way of any profitable discussion of the problem from the evidential point of view. And this indefiniteness is partly due to the fact that the need of observation is not realized, because this factor in animal behaviour has not been distinguished with suflicient clearness. It is worth while, therefore, to devote a short space to a consideration of the relation of this tradition to instinct and intelligence with a view to the focussing of observation on the facts by which it may be further elucidated.

Why

In the first place, it is probable that, as in other modes of animal behaviour, traditional procedure is founded on an instinctive basis. This must be an imitative tendency of the broad follow-my-leader type indicated in the first section of this chapter. And this would afford wide instinctive foundations, which would owe their hereditary character to the fact that, under natural selection, those individuals in the com- and as munity would survive which fell into line with the adaptive well. behaviour of their companions, while those which failed in this respect would be eliminated as more or less isolated out-e siders, standing apart from the social life. In illustration we may take a hypothetical case, founded, however, upon observation. The Rev. S. J. Whitmee, a missionary in Samoa, believested that the tooth-billed pigeon of these islands (Didunculus strigirostris) "has probably been frightened when roosting, or during incubation, by attacks of cats, and has sought safety

in the trees. Learning, from frequent repetition of the fright, that the ground is a dangerous place, it has acquired the habit of building, roosting, and feeding on the high trees; and this habit is now operating for the preservation of this interesting bird, which a few years ago was almost extinct."* Now, in this case, the young birds which followed the lead of those who, under experience, had acquired the habit, would stand a better chance of survival than those who, failing to do so, were caught napping on the ground. In further illustration, we may take the case of two species of rats found by Mr. C. M. Woodford on one of the Solomon Islands. These two species are regarded by Mr. Oldfield Thomas as slightly altered descendants of one parent species, with adaptations due to the fact that, of this original species, some have adopted a terrestrial, others an arboreal life. Thus Mus rex lives in trees, has broad footpads, and a long rasp-like, probably semiprehensile tail; while Mus imperator lives on the ground, has smaller pads, and a short smooth tail. How far the different modes of behaviour in the two species may have been fostered by the influence of tradition we do not know; but it is not improbable that such an influence would be a co-operating factor in the process of segregation, and that in the course of time each form has been adapted to its special environment through the elimination of those individuals which were not in harmony with the conditions of their life.

Such a case-admittedly hypothetical in the interpretation put upon the facts-may help us to see how the general instinctive follow-my-leader tendency might become specialized in certain essential lines of racial behaviour, and how, under natural selection, coincident variations in the line of traditional acts might become more and more definitely inherited as, at first, strong instinctive tendencies, and eventually more stereotyped modes of instinctive behaviour. This, indeed, may have been the mode of origin of some of the social instincts.

Reverting, however, to the stage where the general instinctive follow-my-leader tendency is only partly or incompletely * Proceedings of the Zoological Society, 1874, p. 184.

specialized along particular lines of behaviour, we should have at this stage certain hereditary trends of action, dependent on stimuli afforded by the behaviour of others, but needing, for their guidance to finer issues and more adequate and highly perfected performance, the play of intelligence and the satisfaction of nascent social impulses. In the economy of the hive or the nest there are, no doubt, instinctive tendencies and predispositions; but there is also something more than organic heredity with its transmitted modes of behaviour - analogous to the inherited form and structure of the body or its parts. Consciousness exerts a guiding influence. The insect is not independent of experience, but is capable of profiting by the teachings of that fertile mother of all intelligent behaviour. It is unnecessary, however, to insist on the fact that such insects are something more than instinctive automata, but are guided in their behaviour by the results of experience. Many careful observers lay stress upon this; if, indeed, they do not go further and claim for the social insect the higher rational faculty. "When we see," says Lord Avebury, an ant-hill tenanted by thousands of industrious inhabitants, excavating chambers, forming tunnels, making roads, guarding their home, gathering food, feeding the young, tending their domestic animals-cach one fulfilling its duties industriously, and without confusion-it is difficult altogether to deny to them the gift of reason; and the preceding observations tend to confirm the opinion that their mental powers differ from those of man, not so much in kind as in degree."

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If the term "reason" be here accepted in the broad sense, and not in the narrower sense before indicated, this passage will probably be endorsed by the majority of those who have paid any attention to the subject; save that those who regard "reason," in the more restricted acceptation of the term, as outside any scheme of evolution, may claim that this does constitute a difference in kind and not merely in degree. In any case the passage expresses the conviction of a close and "Scientific Lectures," 2nd edit., p. 140.

singularly unprejudiced observer, that the doings of ants involve conscious guidance in the light of experience individually acquired.

And yet the behaviour of different species of ants, each after its kind, is remarkably constant-so constant that, to use the words of Dr. Peckham in another connection, it is characteristic of the species, and would be an important part of any definition of the insect based upon its habits. And some part of this constancy may be due to tradition, though much of it may result from strong instinctive tendencies which intelligence guides to similar ends, because the conditions are similar in successive generations of social insects.

From the point of view of observation, however, it is particularly difficult to distinguish the part played by tradition as a psychological influence from that played by what we have above described as instinctive imitation. In our study of other modes of instinctive behaviour we can isolate an individual, or group of young individuals, and observe how far certain acts are performed prior to any experience. Thus chicks behave in certain instinctive ways under conditions which preclude their learning from the hen or other older birds-so that tradition cannot be operative. But where social behaviour is concerned, such methods of observation are necessarily excluded—save in such cases as that of the incipient community of ants. For if certain instinctive acts require for their due performance the stimulus of the like performance in others, what is this but a form of instinctive tradition; and how are we to distinguish it + from intelligent tradition, where a psychological factor has freer play and exercises guidance over the performance ? In the present state of our knowledge we can do no more than suggest, as not improbable, that tradition passes through three phases the first in which it is instinctive; the second in which it becomes intelligent through the satisfaction which the due performance of traditional acts arouses in consciousness; and the third in which, at any rate in man, it takes on a rational form, and is made to accord with an ideal scheme, the product of conceptual thought and of reflection on data which

have been generalized and considered in their due relationships. to the scheme which takes definite form in the mind. Whether in the social communities of insects or those of beavers, among mammals, or rooks among birds, tradition has begun to pass into the third or rational stage, we do not know. It may be so, but probably the development along these lines has not been carried far. Presumably in the ant, rook, and beaver anything like an ideal scheme of thought based on reflection, if it exist, is as yet exceedingly indefinite.

But even supposing that no animal has yet risen beyond the second or intelligent stage, it is none the less important to realize that we have here, in animal life, the foundations on which may be raised what may, perhaps, be regarded as onc of the characteristic features of human progress. This charac teristic is the transference of evolution from the organism to the environment handed on from generation to generation! Thus man, "availing himself of tradition, is able to seize upon the acquirements of his anecstors at the point where they left them." Thus "he has slowly accumulated and organized the experience which is almost wholly lost with the cessation of individual life in other animals." + But he is able to do so through the extension, refining, and fixing of that instinctive. and intelligent tradition which begins to take form in animal communities.

V. THE EVOLUTION OF SOCIAL BEHAVIOUR

"Animals of many kinds," said Darwin,‡ "are social; every one must have noticed how miserable horses, dogs, sheep, etc., are when separated from their companions. The most common mutual service in the higher animals is to warn one another of danger. Every sportsman knows how difficul * Weismann, "Essays," vol. ii., p. 50. Huxley, "Collected Essays,” vol. vii.,

p. 155.

"The Descent of Man," vol. i. p. 853, 2nd Ed., 1888. The quotations from Darwin in this paragraph and that which follows are somewhat condensed by a few omissions.

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