# Popular Science Monthly/Volume 50/November 1896/A Dog's Laugh

Layout 4
* A DOG'S LAUGH.
By M. LE VICOMTE D'AIGLUN.
ALPHONSE KARR has said: "Man is the gayest of animals; much more, he is the only gay one, the only one that laughs." Toussenel is equally explicit: "Laughter is a characteristic faculty of man." Gratiolet observes that "when man freely breathes a pure air, fresh and uncontaminated, his mouth dilates slightly, his upper lip reveals more or less of his upper front teeth, and the corners of the mouth gracefully elevate themselves;
* Fig. 1.—Fox Terrier Laughing. From a photograph.
the muscles that determine this movement act at the same time upon his cheeks and raise them, slightly lifting the outer angles of his eyes, which become a little oblique. This movement of easy respiration is called the smile; and the smile of the lips is distinguished in language from the smile of the eyes. The smile of the eyes is in man, however, consecutive to the service of the mouth, and does not depend upon any special muscle. No mammalian animal has the smile of the mouth; but the smile of the eyes exists in the carnivorous animals, and, as it can not depend upon the buccal smile, its determining cause resides in a small muscle that acts on the outer angle of the eye. Dogs, it is known, have this smile of the eyes in a superior degree." Further, he says: "The real and simple smile that is, the movement that lifts the angle of the mouth is exclusively peculiar to the human species. There is nothing like it even in the highest monkeys. Among the carnivores, animals of the genera Ursus (bear), Canis (dog), and ​Hyæna have some movements that resemble the smile, but can not be really compared with it. Below the mammalian animals there is no longer mobility in the face, and consequently no longer a possible smile."
Darwin also admits a sort of smile in dogs, but regards it as a simple grimace: "A pleasurable and excitable state of mind, associated with affection, is exhibited by some dogs in a very peculiar manner; namely, by grinning. This was noticed long ago by Somerville, who says:
"And with a courtly grin the fawning hound Salutes thee cow'ring, his wide op'ning nose Upward he curls, and his large sloe-black eyes Melt in soft blandishments and humble joy.
—The Chase, Book I.
Sir W. Scott's famous Scotch greyhound, Maida, had this habit, and it is common with terriers. I have also seen it in a Spitz and in a sheep dog. Mr. Rivière, who has particularly attended to this expression, informs me that it is rarely displayed in a perfect manner, but is quite common in a lesser degree. The upper lip during the act of grinning is retracted as in snarling, so that the canines are exposed, and the ears are drawn backwards; but the general appearance of the animal clearly shows that anger is not felt. Sir Charles Bell remarks: 'Dogs, in their expression of fondness, have a slight eversion of the lips, and grin and sniff amid their gambols in a way that resembles laughter.' Some persons speak of this grin as a smile, but if it had been really a smile we should see a similar though more pronounced movement of the lips and ears when dogs utter their bark of joy; but this is not the case, although the bark of joy often follows a grin."
Notwithstanding my profound respect for the names of Darwin and the other authors from whom I have quoted, I take the liberty of remarking that it is hard to laugh and bark at the same time, and that some dogs employ laughter to express their joy while at the same time wagging their tails and exhibiting all the other signs peculiar to their kind.
We must not push the analysis too far, for fear of going beyond the truth. Laughter to everybody is nothing else than a joyous expression of the face given by the movement of the mouth. No one certainly would take the trouble to find, in order to know it, by what muscles it is produced.
​Now, is not that a good laugh, quite free and affectionate, that is represented in the picture, Fig. 1, taken from the instantaneous photograph of a little fox-terrier bitch in my possession,
* Fig. 2.—A Collie "Laughing all Over." From a photograph.
which puts on this expression very prettily every time it would manifest pleasure or a great joy? Fig. 2 gives also the expression of a dog laughing all over. It is the portrait of a collie bitch. The animal has a very pleasant physiognomy. The French language has an expression, canin, for canine laughter, which the dictionaries define by saying that it is produced by the contraction of the canine muscle, or the muscle that lifts the angle of the lips; and they give it as the synonym of sardonic laughter, because it is produced on only one side of the mouth. Fig. 1 shows that this synonymy is not always just.
A friend of mine has a terrier which also laughs, and which has after a few months taught a spaniel, its habitual companion, to laugh.
This education of one animal by another is not so rare as might be supposed. I knew a little dog in Havana, a great friend of the cat of the house, that took from it the habit of moistening its paws with its tongue and washing its face with them.—Translated for the Popular Science Monthly from La Nature.
* ↑ Gratiolet. De la Physionomie, p. 25.
* ↑ Gratiolet. De la Physionomie, p. 169.
* ↑ The Expression of the Emotions in Man and Animals, p. 120.
* ↑ The Anatomy of Expression, 1844, p. 140.