The voice of the chimpanzee is strong, clear, and in captivity it is very much in evidence. Two of its moderate tones are almost musical. It is heard when the animal says, coaxingly, "Who'-oe!

Who'-oe!" A dozen times a day, our large specimens indulge in spells of loud yelling, purely for their own amus.e.m.e.nt. Their strident cry sounds like "Hoo-hoo-hoo-hoo! _Wah'_-hoo!

_Wah'_-hoo! Hoo'-hoo! _Wah_-h-h-h! _Wah_-h-h!" The second combination, "Wah-hoo," consists of two sounds, four notes apart.

It is with their voices that chimpanzees first manifest their pleasure at seeing cherished friends of the human species, or their anger. Their recognition, and their exuberant joy on such occasions, is quite as apparent to every observer as are the manifestations of welcome of demonstrative human beings.

Like all other groups of species, the apes of various genera now living vary widely in their mentalities. The chimpanzee has the most alert and human-like mind but with less speed the orang-utan is a good second. The average captive gorilla, if judged by existing standards for ape mentality, is a poor third in the anthropoid scale, below the chimp and orang; but since the rise of Major Penny's family-pet gorilla, named John, we must revise all our former views of that species, and concede exceptions.

In studying the mental status of the primates I attach great importance to the work and results of the professional trainers who educate animals for stage performances. If the trainer does not know which are the brightest species of apes, baboons and monkeys, then who does? Their own fortunes depend upon their estimate of comparative mentality in the primates. Fortunately for our purposes, the minds of the most intelligent and capable apes, baboons, and monkeys have been partially developed and exploited by stage trainers, and to a far less extent by keepers in zoological parks. Some wonderful results have been achieved, and the best of these have been seen by the public in theatres, in traveling shows and in zoological parks. All these performances have greatly interested me, because they go so far as measures of mental capacity. I wish to make it clear that I take them very seriously.

[Ill.u.s.tration with caption: PORTRAIT OF A HIGH-CASTE CHIMPANZEE "Baldy" was an animal of fine intelligence and originality in thought. He was a natural comedian]

While many of the acts of trained animals are due to their power of mimicry and are produced by imitation rather than by original thought, even their imitative work reveals a breadth of intelligence, a range of memory and of activity and precision in thought and in energy which no logical mind can ignore. To say that a chimpanzee who can swing through thirty or forty different acts "does not think" and "does not reason," is to deny the evidence of the human senses, and fall outside the bounds of human reason.

Training Apes for Performances. As will appear in its own chapter, there is nothing at all mysterious in the training of apes. The subject must be young, and pliant in mind, and of cheerful and kind disposition. The poor subjects are left for cage life. The trainer must possess intelligence of good quality, infinite patience and tireless industry. Furthermore, the stage properties must be ample. An outfit of this kind can train any ape that is mentally and physically a good subject. Of course in every animal species, wild or domestic, there are individuals so dull and stupid that it is inexpedient to try to educate them.

The chimpanzee Suzette who came to us direct from the vaudeville stage performed every summer in her open-air "arena cage," until she entered motherhood, which put an end to her stage work. She was a brilliant "trick" bicycle rider. She could stand upright on a huge wooden ball, and by expert balancing and foot-work roll it up a steep incline, down a flight of stairs, and land it safely upon the stage, without once losing her balance or her control.

She was entirely at home on roller skates, and when taken out upon the pavement of Baird Court she would go wildly careering around the large gra.s.s plat at high speed.

All the above acts were acrobatic feats that called for original thought and action, and were such as no dull mind and body could exert. All the training skill in the world could not take a machine and teach it to ride a bicycle through a collection of bottles, and an intelligent ape is a million years from being a "machine in fur and feathers."

More than once I have been astounded by the performances of apes on the stage. Mr. J. S. Edwards' orang-utan Joe was a very capable animal, and his performances were wonderful. He could use a hammer in driving nails, and a screwdriver in inserting and extracting screws, with wonderful dexterity.

The most remarkable chimpanzee performance that I ever saw was given in a New York theatre in 1909. The star actor was a fine male animal about six years old, called Peter. I made a complete record of his various acts, and the program was as follows

PERFORMANCE OF PETER, A CHIMPANZEE

Stage properties: a suit of clothes, shoes, chair, table, bed, bureau, hatrack, candle, cigarette, match, cuspidor, roller skates, bottles, flag, inclined plane and steps; plate, napkin, cup, spoon, teapot.

As Peter entered, he bowed to the audience, took off his cap and hung it upon a hatrack. He went to the table, seated himself in the chair, unfolded and put on a napkin, and with a string fastened it in place under his chin. With a fork he speared some slices of banana and ate them. Into his tumbler he poured liquid from a bottle, drank, then corked the bottle. Next, he poured tea into a cup, put in sugar and cream, took tea from the spoon, then drank from the cup. After that he took a toothpick and used it elaborately.

Striking a match he lit a cigarette, and smoked. In perfect man- fashion he took the cigarette between his fingers, gave his keeper a light, smoked again, and blew puffs of smoke first from one corner of his mouth and then the other. Then he elaborately spat into the cuspidor.

Next in order he went to the bureau, cleaned his teeth with a tooth-brush, brushed his hair on both sides, looked into the mirror and powdered his face.

Finally he bit a coin and put it on the keeper's plate as a tip.

He pulled off his coat, took off his cuffs and vest, and thus half undressed he joyously danced about, beating a tambourine. Then he removed his shirt, trousers, shoes, garters and socks. Lighting his candle he walked to his bed, blew out the candle and went to bed.

Very soon he rose, put on his trousers and a pair of roller skates and playfully pursued a young woman who ran before him. His use of the roller skates was excellent.

The stage was cleared of furniture, and a bicycle was brought out.

He mounted it and started off, at the first trial, and swiftly rode around the stage about fifteen times. While riding he took off his cap and waved it. He rode up an inclined plane and down four steps without falling off, repeating for an encore,--but here he became peeved about something.

Five bottles were set in a figure 8, and he rode between them several times. At last he took up a bottle and drank out of it.

Then he drank out of a tumbler, all while riding. After much flag- waving and swift riding, Peter stopped at the center of the stage, dismounted, bowed, clapped his hands vigorously and retired.

Peter's performance was remarkable because of the great length of it, the absolute skill and precision of it, and the animal's easy mastery of every situation. There was a notable absence of hesitations and mistakes, and of visible direction. The trainer seemed to do nothing save to a.s.sist with the stage properties, just as an a.s.sistant helps any acrobat through the property business of his act. If any commands or signs were given, the audience was not aware of it. Later on I learned that sometimes Peter did not perform with such spirit, and required some urging to be prompt. The trainer was kept hustling to keep up with his own duties. The animal seemed to remember, and I believe he did remember, the sequence of a performance of _fifty-six separate acts!_

When I witnessed Peter's performance in New York, saw the length of it and noted the immense amount of nervous energy that each performance used up, I made the prediction that he could not for one year endure such a strain. It was reported to me that he died nine months from that time.

In October, 1909, when Peter went to Philadelphia, he was frequently and closely studied and observed by Dr. Lightner Witmer, professor of psychology at the University of Pennsylvania, and his mentality was tested at the laboratory of the University.

Dr. Witmer's conclusions, as set forth in a paper in the December (1909) issue of the _Psychological Clinic,_ are of very great interest. He approached Peter's first performance in a skeptical frame of mind. I gladly waive the opportunity to express my own views regarding Peter in order to put upon the stand a more competent witness. Hear Dr. Witmer:

"As I entered the theatre," he says, "my feelings were commingled interest and doubt. My doubts were bred from knowledge of the difficulty of judging the intelligence of an animal from a stage performance. So-called educated horses and even educated seals and fleas have made their appeal in large number to the credulity of the public. Can any animal below man be educated in the proper sense of the word? Or is the animal mind susceptible of nothing more than a mechanical training, and only given the specious counterfeit of an educated intelligence when under the direct control of the trainer?

"Since that day I have seen Peter in five public performances, have tested him at my psychological clinic and privately on three occasions. I now believe that in a very real sense the animal is himself giving the stage performance. He knows what he is doing, he delights in it, he varies it from time to time, he understands the succession of tricks which are being called for, he is guided by word of mouth without any signal open or concealed, and the function of his trainer is exercised mainly to steady and control.

"I am prepared to accept the statement of his trainers, Mr. and Mrs. McArdle, that Peter's proficiency is not so much the result of training as of downright self-education."

Peter was put through many of the tests which Dr. Witmer uses for the study of backward children. He performed many of these tests in a very satisfactory manner. He was able to string beads the first time he tried it. He put pegs in the ordinary kindergarten pegging board. He opened and closed a very difficult lock. He used hammer and screw driver, and distinguished without any mistake between nails and screws. A peculiar kind of hammer was given to him in order to fool him, but Peter was not fooled. He felt both ends of the hammer and used the flat end instead of the round end.

Showing his initiative during the tests, Peter got away from those who were watching him and darted for a washstand, quickly turned the faucet and put his mouth to the spigot and secured a drink before he was s.n.a.t.c.hed away by his trainers. He understood language and followed instructions without signs. He was able to say "mamma," and Doctor Witmer taught him in five minutes to give the sound of "p." The most remarkable performance was making the letter "w" on the blackboard, in which he imitated Doctor Witmer's movements exactly, and reproduced a fair copy of the letter.

The last four paragraphs reproduced above have been copied from an article which appeared in the Philadelphia _Public Ledger_ on December 17, 1909.

Dr. Witmer declares that the study of this ape's mind is a subject fit, not for the animal psychologist, but for the child psychologist.

Suzette's Failure in Maternal Instinct. As a closing contribution to our observations on the chimpanzee, I must record a tragic failure in maternal instinct, as well as in general intelligence, in a chimpanzee.

In 1919 our two fine eight-year old chimpanzees, Boma and Suzette, were happily married. It was a genuine love match, and strictly monogamous at that; for while big f.a.n.n.y Chimp in the cage next door to Boma loved Boma and openly courted him, he was outrageously indifferent to her, and even scorned her. After seven months of gestation, a very good baby was born to Suzette, quite naturally and successfully. Boma's shouts of excitement and delight carried half a mile throughout the Park. Everything looked most auspicious for the rearing of a wonderful cage-bred and cage-born chimpanzee, the second one ever born in captivity.

Instead of carrying her infant astride her hip, as do orang mothers, and the coolie women of India, Suzette astonished us beyond measure by tucking it _into her groin,_ between her thigh and her abdomen, head outward. It was a fine place,--warm and soft,--but not good when overdone! When Suzette walked, as she freely did, she held up the leg responsible for the baby, to hold it securely in place, and walked upon the other foot and her two hands. About all this there was one very bad thing. The baby was perfectly helpless! As long as the mother chose to keep it in her groin prison, it could not get free.

Suzette was completely isolated, kept absolutely quiet, and every chance was given her to go on with the functions of motherhood.

Her b.r.e.a.s.t.s contained plenty of milk, and the flow was due to start on the second day after the infant's arrival.

Day and night the baby was jealously confined in that ma.s.sive and powerful groin,--and _under too much pressure!_ When the baby cried, and kicked, and struggled to get free, Suzette would nervously rearrange her straw bed, carefully pick from the tiny fingers every straw that they had clutched, and settle down again.

If the struggle was soon renewed, Suzette would change the infant over to the other groin, and close upon it as before.

Sleeping or waking, walking, sitting or lying down, she held it there. If we attempted to touch the infant, the mother instantly became savage and dangerous. Not one human finger was permitted to touch it. For hours, and for days, we anxiously watched for nursing to begin; but in vain. At last we became almost frantic from the spectacle of the infant being slowly starved to death because the mother did not realize that it needed her milk, and that she alone could promote nursing. _Her mother instinct utterly failed to supply the link that alone could connect infancy to motherhood, and furnish life._

Of course this failure was due to poor Suzette's artificial life, and unnatural surroundings. Had she been all alone, in the depths of a tropical forest, Nature would have proceeded along her usual lines. But in our Primate House, Suzette felt that her infant was surrounded by a host of strange enemies, from whom it must be strongly and persistently _guarded and defended._ That was the idea that completely dominated her mind, ruled out all human help, and blocked the main process of nature.

During the eight days that the infant lived, it was able to reach her breast and nurse only once, for about one minute; and then back it went to its prison, where it died from sheer lack of nourishment.

In 1920, that same history was repeated, except that on this occasion our Veterinary Surgeon, Dr. W. Reid Blair, worked (on the fifth day) for seven hours without intermission to stupefy Suzette with chloroform, or other opiates, sufficiently to make it possible to remove the baby without a fight with the mother and its certain death. Owing to her savage temper all the work had to be done between iron bars, to keep from losing hands or arms, and the handicap on the human hand was too great. Even when Suzette had received chloroform for an hour and twenty minutes, and was regarded as _half dead,_ at the first touch of a human finger upon her thigh she instantly aroused and sprang up, raging and ready for battle.

The whole effort failed. To rope Suzette and attempt to control her by force would have been sheer folly, or worse. In such a struggle the infant would have been torn to pieces.

The second one died as the first one did, and for an awful week we were unable to gain possession of the decomposing cadaver. Suzette knew that something was wrong, and she realized the awful odor, but that idea of defense of her offspring obscured all others. In maintaining her possession of that infant, nothing could surpa.s.s the cunning of that ape mother. Will we ever succeed in outwitting her, and in getting one of her babies alive into a baby incubator?

Who can say?

X

THE TRUE MENTAL STATUS OF THE GORILLA