The Expression of Emotion in Man and Animals, Charles Darwin [snow like ashes series txt] 📗

Some species of deer, when savage, display far more expression than do cattle, sheep, or goats, for, as has already been stated, they draw back their ears, grind their teeth, erect their hair, squeal, stamp on the ground, and brandish their horns.

One day in the Zoological Gardens, the Formosan deer (_Cervus pseudaxis_) approached me in a curious attitude, with his muzzle raised high up, so that the horns were pressed back on his neck; the head being held rather obliquely.

From the expression of his eye I felt sure that he was savage; he approached slowly, and as soon as he came close to the iron bars, he did not lower his head to butt at me, but suddenly bent it inwards, and struck his horns with great force against the railings.

Mr. Bartlett informs me that some other species of deer place themselves in the same attitude when enraged.

Monkeys.—The various species and genera of monkeys express their feelings in many different ways; and this fact is interesting, as in some degree bearing on the question, whether the so-called races of man should be ranked as distinct species or varieties; for, as we shall see in the following chapters, the different races of man express their emotions and sensations with remarkable uniformity throughout the world. Some of the expressive actions of monkeys are interesting in another way, namely from being closely analogous to those of man.

As I have had no opportunity of observing any one species of the group under all circumstances, my miscellaneous remarks will be best arranged under different states of the mind.

[9] `Land and Water,’ 1869, p. 152.

Pleasure, joy, affection—It is not possible to distinguish in monkeys, at least without more experience than I have had, the expression of pleasure or joy from that of affection.

Young chimpanzees make a kind of barking noise, when pleased by the return of any one to whom they are attached.

When this noise, which the keepers call a laugh, is uttered, the lips are protruded; but so they are under various other emotions.

Nevertheless I could perceive that when they were pleased the form of the lips differed a little from that assumed when they were angered. If a young chimpanzee be tickled—

and the armpits are particularly sensitive to tickling, as in the case of our children,—a more decided chuckling or laughing sound is uttered; though the laughter is sometimes noiseless.

The corners of the mouth are then drawn backwards; and this sometimes causes the lower eyelids to be slightly wrinkled.

But this wrinkling, which is so characteristic of our own laughter, is more plainly seen in some other monkeys. The teeth in the upper jaw in the chimpanzee are not exposed when they utter their laughing noise, in which respect they differ from us.

But their eyes sparkle and grow brighter, as Mr. W. L. Martin,[10]

who has particularly attended to their expression, states.

[10] `Natural History of Mammalia,’ 1841, vol. 1. pp. 383, 410.

Young Orangs, when tickled, likewise grin and make a chuckling sound; and Mr. Martin says that their eyes grow brighter. As soon as their laughter ceases, an expression may be detected passing over their faces, which, as Mr. Wallace remarked to me, may be called a smile.

I have also noticed something of the same kind with the chimpanzee.

Dr. Duchenne—and I cannot quote a better authority—informs me that he kept a very tame monkey in his house for a year; and when he gave it during meal-times some choice delicacy, he observed that the corners of its mouth were slightly raised; thus an expression of satisfaction, partaking of the nature of an incipient smile, and resembling that often seen on the face of main, could be plainly perceived in this animal.

The Cebus azarae,[11] when rejoiced at again seeing a beloved person, utters a peculiar tittering (_kichernden_) sound. It also expresses agreeable sensations, by drawing back the corners of its mouth, without producing any sound. Rengger calls this movement laughter, but it would be more appropriately called a smile. The form of the mouth is different when either pain or terror is expressed, and high shrieks are uttered. Another species of Cebus in the Zoological Gardens (_C. hypoleucus_) when pleased, makes a reiterated shrill note, and likewise draws back the corners of its mouth, apparently through the contraction of the same muscles as with us.

So does the Barbary ape (Inuus ecaudatus) to an extraordinary degree; and I observed in this monkey that the skin of the lower eyelids then became much wrinkled. At the same time it rapidly moved its lower jaw or lips in a spasmodic manner, the teeth being exposed; but the noise produced was hardly more distinct than that which we sometimes call silent laughter. Two of the keepers affirmed that this slight sound was the animal’s laughter, and when I expressed some doubt on this head (being at the time quite inexperienced), they made it attack or rather threaten a hated Entellus monkey, living in the same compartment.

Instantly the whole expression of the face of the Inuus changed; the mouth was opened much more widely, the canine teeth were more fully exposed, and a hoarse barking noise was uttered.

[11] Rengger (`Sagetheire von Paraquay’, 1830, s. 46) kept these monkeys in confinement for seven years in their native country of Paraguay.

The Anubis baboon (_Cynocephalus anubis_) was first insulted and put into a furious rage, as was easily done, by his keeper, who then made friends with him and shook hands. As the reconciliation was effected the baboon rapidly moved up and down his jaws and lips, and looked pleased. When we laugh heartily, a similar movement, or quiver, may be observed more or less distinctly in our jaws; but with man the muscles of the chest are more particularly acted on, whilst with this baboon, and with some other monkeys, it is the muscles of the jaws and lips which are spasmodically affected.

I have already had occasion to remark on the curious manner in which two or three species of Alacacus and the Cynopithecus niger draw back their ears and utter a slight jabbering noise, when they are pleased by being caressed. With the Cynopithecus (fig. 17), the corners of the mouth are at the same time drawn backwards and upwards, so that the teeth are exposed.

Hence this expression would never be recognized by a stranger as one of pleasure. The crest of long hairs on the forehead is depressed, and apparently the whole skin of the head drawn backwards.

The eyebrows are thus raised a little, and the eyes assume a staring appearance. The lower eyelids also become slightly wrinkled; but this wrinkling is not conspicuous, owing to the permanent transverse furrows on the face.

Painful emotions and sensations.—With monkeys the expression of slight pain, or of any painful emotion, such as grief, vexation, jealousy, &c., is not easily distinguished from that of moderate anger; and these states of mind readily and quickly pass into each other.

Grief, however, with some species is certainly exhibited by weeping.

A woman, who sold a monkey to the Zoological Society, believed to have come from Borneo (_Macacus maurus_ or M. inornatus of Gray), said that it often cried; and Mr. Bartlett, as well as the keeper Mr. Sutton, have repeatedly seen it, when grieved, or even when much pitied, weeping so copiously that the tears rolled down its cheeks.

There is, however, something strange about this case, for two specimens subsequently kept in the Gardens, and believed to be the same species, have never been seen to weep, though they were carefully observed by the keeper and myself when much distressed and loudly screaming.

Rengger states[12] that the eyes of the Cebus azarae fill with tears, but not sufficiently to overflow, when it is prevented getting some much desired object, or is much frightened.

Humboldt also asserts that the eyes of the Callithrix sciureus

“instantly fill with tears when it is seized with fear;”

but when this pretty little monkey in the Zoological Gardens was teased, so as to cry out loudly, this did not occur.

I do not, however, wish to throw the least doubt on the accuracy of Humboldt’s statement.

The appearance of dejection in young orangs and chimpanzees, when out of health, is as plain and almost as pathetic as in the case of our children.

This state of mind and body is shown by their listless movements, fallen countenances, dull eyes, and changed complexion.

[12] Rengger, ibid. s. 46. Humboldt, `Personal Narrative, Eng. translat.

vol. iv. p. 527. {Illust. caption = FIG. 16.—Cynopithecus niger, in a placid condition.

Drawn from life by Mr. Wolf. FIG. 17.—The same, when pleased by being caressed.}

Anger.—This emotion is often exhibited by many kinds of monkeys, and is expressed, as Mr. Martin remarks,[13] in many different ways.

“Some species, when irritated, pout the lips, gaze with a fixed and savage glare on their foe, and make repeated short starts as if about to spring forward, uttering at the same time inward guttural sounds.

Many display their anger by suddenly advancing, making abrupt starts, at the same time opening the mouth and pursing up the lips, so as to conceal the teeth, while the eyes are daringly fixed on the enemy, as if in savage defiance. Some again, and principally the long-tailed monkeys, or Guenons, display their teeth, and accompany their malicious grins with a sharp, abrupt, reiterated cry.”

Mr. Sutton confirms the statement that some species uncover their teeth when enraged, whilst others conceal them by the protrusion of their lips; and some kinds draw back their ears.

The Cynopithecus niger, lately referred to, acts in this manner, at the same time depressing the crest of hair on its forehead, and showing its teeth; so that the movements of the features from anger are nearly the same as those from pleasure; and the two expressions can be distinguished only by those familiar with the animal.

Baboons often show their passion and threaten their enemies in a very odd manner, namely, by opening their mouths widely as in the act of yawning. Mr. Bartlett has often seen two baboons, when first placed in the same compartment, sitting opposite to each other and thus alternately opening their mouths; and this action seems frequently to end in a real yawn.

Mr. Bartlett believes that both animals wish to show to each other that they are provided with a formidable set of teeth, as is undoubtedly the case. As I could hardly credit the reality of this yawning gesture, Mr. Bartlett insulted an old baboon and put him into a violent passion; and he almost immediately thus acted.

Some species of Macacus and of Cereopithecus[14] behave in the same manner. Baboons likewise show their anger, as was observed by Brehin with those which he kept alive in Abyssinia, in another manner, namely, by striking the ground with one hand, “like an angry man striking the table with his fist.”

I have seen this movement with the baboons in the Zoological Gardens; but sometimes the action seems rather to represent the searching for a stone or other object in their beds of straw.

[13] Nat. Hist. of Mammalia, 1841, p. 351.

Mr. Sutton has often observed the face of the Macacus rhesus, when much enraged, growing red. As he was mentioning this to me, another monkey attacked a rhesus, and I saw its face redden as plainly as that of a man in a violent passion. In the course of a few minutes, after the battle, the face of this monkey recovered its natural tint.

At the same time that the face reddened, the naked posterior