Mental Evolution in Man: Origin of Human Faculty

by George John Romanes

So much, then, for the power of sign-making displayed by the Hymenoptera. As I have not much evidence of sign-making in any of the other Invertebrata,[62] I shall pass on at once to the Vertebrata.

Ray observed the different tones used by the common hen, and found them uniformly significant of different ideas, or emotional states; therefore we may properly regard this as a system of language, though of a very rudimentary form. He distinguishes altogether nine or ten distinct tones, which are severally significant of as many distinct emotions and ideas—namely, brooding, leading forth the brood, finding food, alarm, seeking shelter, anger, pain, fear, joy or pride in having laid an egg. Houzeau, who independently observed this matter, says that the hen utters at least twelve significant sounds.[63]

Many other cases could be given among Birds, and a still greater number among Mammals, of vocal tones being used as intentionally significant of states of feeling and of definite ideas; but to save space I will only render a few facts in a condensed form.

“In Paraguay, the Cebus azaræ when excited utters at least six distinct sounds, which excite in other monkeys similar emotions (Rengger).... It is a more remarkable fact that the dog, since being domesticated, has learned to bark in at least four or five distinct tones: ... the bark of eagerness, as in the chase; that of anger, as well as growling; the yelp, or howl of despair, when shut up; the baying at night; the bark of joy when starting on a walk with his master; and the very distinct one of demand or supplication, as when wishing for a door or window to be opened.”[64]

I may next briefly add allusions to those instances of the use of signs by mammals which are fully detailed in Animal Intelligence.

Mr. S. Goodbehere tells me of a pony which used to push back the inside bolt of a gate in its paddock, and neigh for an ass which was loose in the yard beyond; the ass would then come and push up the outside latch, thus opening the gate and releasing the pony (p. 333).

With respect to gestures, Mrs. K. Addison wrote me of her jackdaw—which lived in a garden, and which she usually supplied with a bath—reminding her that she had forgotten to place the bath, by coming before her and going through the movements of ablution upon the ground (p. 316).

Youatt gives the case of a pig which was trained to point game with great precision (pp. 339, 340), and this, as in the case of the dog, implies a high development of the sign-making faculty. Every sportsman must know how well a setter understands its own pointing, and also the pointing of other dogs, as gesture-signs. As regards its own pointing, if at any distance from the sportsman, the animal will look back to see if the “point” has been noticed; and, if it has, the point will be much more “steady” and prolonged than if the animal sees that it has not been observed. As regards the pointing of other dogs, the “backing” of one by another means that as soon as one dog sees another dog point he also stands and points, whether or not he is in a position to scent the game. In my previous work, while treating of artificial instincts, I have shown (as Mr. Darwin had previously remarked) that in well-bred sporting dogs a tendency to “back,” more or less pronounced, is intuitive. But I have also observed among my own setters that even in cases where a young dog does not show any innate disposition to “back,” by working him with other dogs for a short time he soon acquires the habit, without any other instruction than that which is supplied by his own observation. I have also noticed that all sporting dogs are liable to be deceived by the attitude which their companions strike when defæcating; but this is probably due to their line of sight being so much lower than that of a man, that slight differences of attitude are not so perceptible to them as to ourselves.

Major Skinner writes of a large wild elephant which he saw on a moonlight night coming out of a wood that skirted some water. Cautiously advancing across the open ground to within a hundred yards of the water, the animal stood perfectly motionless—the rest of the herd, still concealed in the wood, being all the while so quiet and motionless that not the least sound proceeded from them. Gradually, after three successive advances, halting some minutes after each, he moved up to the water’s edge, in which however he did not think proper to quench his thirst, but remained for several minutes listening in perfect stillness. He then returned cautiously and slowly to the point at which he had issued from the wood, whence he came back with five other elephants, with which he proceeded, somewhat less slowly than before, to within a few yards of the tank, where he posted them as patrols. He then re-entered the wood and collected the whole herd, which must have amounted to between eighty and a hundred, and led them across the open ground, with the most extraordinary composure and quiet, till they came up to the five sentinels, when he left them for a moment and again made a reconnaissance at the edge of the tank. At last, being apparently satisfied that all was safe, he turned back, and obviously gave the order to advance; “for in a moment,” says Major Skinner, “the whole herd rushed to the water, with a degree of unreserved confidence so opposite to the caution and timidity which had marked their previous movements, that nothing will ever persuade me that there was not rational and preconcerted co-operation throughout the whole party”—and so, of course, some definite communication by signs (p. 401).