he used it good-naturedly to hector his cage-mate, a female
chimpanzee smaller than himself. That, however, was of trifling
interest. The day on which he made the discovery that he could
break the wooden one and one-half inch horizontal bars that were
held out from his cage walls on cast iron brackets, was for him a
great day. Before his discovery was noted by the keepers he had
joyfully destroyed two bars, and with a broken piece used as a
lever was attacking a third. These bars were promptly replaced by
larger bars, of harder wood, but screwed to the same cast-iron
brackets that had carried the first series.
For a time, the heavier bars endured; but in an evil moment the
ape swung his trapeze bar, of two-inch oak, far over to one side
of his cage, and applied the bar as a lever, inside of a
horizontal bar and from above. The new force was too much for the
cast-iron brackets, and one by one they gave way. Some were broken
off, and others were torn from the wall by the breaking of the
screws that held them. Knowing that all those brackets
must be changed immediately, Dohong was left to destroy them;
which he did, promptly and joyfully. We then made heavy
brackets of flat wrought iron bars, 1/2 by 21/2 inches, unbreakable
even with a lever. These were screwed on with screws
so large and heavy that our carpenters knew they were quite
secure.
[Illustration caption: THE LEVER THAT OUR ORANG-UTAN INVENTED, AND
THE WAY HE APPLIED IT By W. A. Camadeo, in the "Scientific
American," 1907]
In due time, Dohong tested his lever upon the bars with their new
brackets, and at first they held securely. Then he engaged Polly,
his chimpanzee companion, to assist him to the limit of her
strength. While Dohong pulled on the lever, Polly braced her
absurd little back against the wall, and pushed upon it, with all
her strength. At first nothing gave way. The combined strength
exerted by the three brackets was not to be overcome by prying at
the horizontal bar itself. It was then that Dohong's inventive
genius rose to its climax. He decided to attack the brackets
singly, and conquer them one by one. On examining the situation
very critically, he found that each bracket consisted of a right-
angled triangle of wrought iron, with its perpendicular side
against the wall, its base uppermost, and its hypotenuse out in
the air. Through the open centre of the triangle he introduced the
end of his trapeze bar, chain and all, as far as it would go, then
gave a mighty heave. The end of his lever was against the wall,
and the power was applied in such a manner that few machine screws
could stand so great a strain. One by one, the screws were torn
out of the wood, and finally each bracket worked upon was torn
off.
But there was one exception. The screws of one bracket were so
firmly set in a particularly hard strip of the upright tongued-
and-grooved yellow pine flooring that formed the wall, the board
itself was finally torn out, full length! The board was four
inches wide, seven-eighths of an inch thick, and seven feet long.
Originally it was so firmly nailed that no one believed that it
could be torn from its place. [Footnote: In the Winter of 1921
about a dozen newspapers in the United States published a
sensational syndicated article, occupying an entire page, in which
all of Dohong's lever discovery and cage-wrecking performances
were reported as of recent occurrence, and credited to a stupid
and uninteresting young orang called Gabong, now in the Zoological
Park, that has not even the merit of sufficient intelligence to
maintain a proper state of bodily uprightness, let alone the
invention of mechanical principles.]
Without delay, Dohong started in with his lever to pry off the
remaining boards of the wall, but this movement was promptly
checked. Our next task consisted in making long bolts by which the
brackets of the horizontal bars were bolted entirely through the
partition walls and held so powerfully on the other side that even
the lever could not wreck them.
As soon as the brackets were made secure, Dohong turned his
attention to the two large sleeping boxes which were built very
solidly on the balcony of his cage. Both of those structures he
tore completely to pieces,--always working with the utmost good
nature and cheerfulness. Realizing that they could not exist in
the cage with him, we gave him a permit to tear them out--and save
the time of the carpenters.
Dohong's use of his lever was seen by hundreds of visitors, and
one frequent visitor to the Park, Mr. L. A. Camacho, an engineer,
was so much impressed that he published in the _Scientific
American_ an illustrated account of what he saw.
For a long period, Dohong had been more or less annoyed by the
fact that he could not get his head out between the front bars of
his cage, and look around the partition into the home of his next-
door neighbor. Very soon after he discovered the use of the lever,
he swung his trapeze bar out to the upper corner of his cage,
thrust the end of it out between the first bar and the steel
column of the partition, and very deftly bent two of the iron bars
outward far enough so that he could easily thrust his head outside
and have his coveted look.
One of our later and largest orangs made a specialty of twisting
the straw of his bedding into a rope six or seven feet long, then
throwing it over his trapeze bar and swinging by it, forward and
back.
Time and space will not permit the enumeration of the various
things done by that ape of mechanical mind with his swinging rope
and his trapeze, with ropes of straw _twisted by himself,_
with keys, locks, hammer, nails and boxes. Any man who can witness
such manifestations as those described above, and deny the
existence in the animal of an ability to reason from cause to
effect, must be prepared to deny the evidence of his own senses.
The individual variations between orangs, as also between
chimpanzees, are great and striking. It may with truth be said
that no two individuals of either species are really quite alike
in physiognomy, temperament and mental capacity. As subjects for
the experimental psychologist, it is difficult to see how any
other could be found that would be even a good second in living
interest to the great apes. The facts thus far recorded, so I
believe, present only a suggestion of the rich results that await
the patient scientific investigator. In the year 1915 Dr. Robert
M. Yerkes, of Harvard University, conducted at Montecito,
southern California, in a comfortable primate laboratory, six
months of continuous and diligent experiments on the behavior of
orang-utans and monkeys. His report, published under the title of
"The Mental Life of Monkeys and Apes: A Study of Ideational
Behavior," is a document of much interest and value. Dr. Yerkes'
use of the orang-utan as a subject was a decided step forward in
the study of "animal behavior" in America.
IX
THE MAN-LIKENESS OF THE CHIMPANZEE
During the past twenty years, millions of thinking people have
been startled, and not a few shocked, by the amazing and uncanny
human-likeness of the performances of trained chimpanzees on the
theatrical stage. Really, when a well trained "chimp" is dressed
from head to foot like a man, and is seen going with quickness,
precision and spirit through a performance half an hour in length,
we go away from it with an uncomfortable feeling that speech is
all that he lacks of being a citizen.
In 1904 the American public saw Esau. Next came Consul,--in about
three or four separate editions! In 1909 we had Peter. Then came I
know not how many more, including the giant Casey and Mr. Garner's
Susie; and finally in 1918 our own Suzette. The theatre-going
public has been well supplied with trained chimpanzees, and the
mental capacity of that species is now more widely known and
appreciated than that of any other wild animal except the Indian
elephant.
There are several reasons why chimpanzees predominate on the
stage, and why so few performing orang-utans have been seen. They
are as follows:
1. The orang is sanguine, and slower in execution than the nervous
chimpanzee.
2. The feet of the orang are not good for shoes, and biped work.
3. The orang is rather awkward with its hands, and finally,
4. There are fully twice as many chimps in the market.
But the chimpanzee has certain drawbacks of his own. His nervous
temper and his forced-draught activities soon wear him out. If he
survives to see his sixth or seventh year, it is then that he
becomes so strong and so full of ego that he becomes dangerous and
requires to be retired.
Bright minds are more common among the chimpanzee species than
among the orangs. Three chimps out of every five are good for
training, but not more than two orangs out of five can be
satisfactorily developed.
Some sensitive minds shrink from the idea that man has "descended"
from the apes. I never for a moment shared that feeling. I would
rather descend from a clean, capable and bright-minded genus of
apes than from any unclean, ignorant and repulsive race of the
genus _Homo._ In comparing the chimpanzees of Fernan Vaz
with the Canoe Indians of the Strait of Magellan and other human
tribes we could name, I think the former have decidedly the best
of it. There are millions of members of the human race who are
more loathsome and repulsive than wild apes.
The face of the chimpanzee is highly mobile, and the mouth, lips,
eyes and voice express the various emotions of the individual
with a degree of clearness and precision second only to the facial
expression of man himself. In fact, the face of an intelligent
chimpanzee or orang-utan is a fairly constant index of the state
of mind of the individual. In their turn, those enormously
expansive lips and keen brown eyes express contentment, doubt,
fear and terror; affection, disapproval, jealousy, anger, rage;
hunger and satiety; lonesomeness and illness.
The lips of the chimpanzee afford that animal several perfectly
distinct expressions of the individual's mind and feelings. While
it is not possible to offer a description of each which will
certainly be recognizable to the reader, the two extremes will at
least be appreciated. When coaxing for food, or attention, the
lips are thrust far out beyond the teeth, and formed into a funnel
with the small end outermost. When the chimpanzee flies into a
rage at some real or fancied offense, the snarling lips are drawn
back, and far up and down, until the teeth and gums are fully
exposed in a ghastly threat of attack. At the same time, the voice
gives forth shrill shrieks of rage, correctly represented by the
syllable "Ee-ee-ee!", prolonged, and repeated with great force,
three or four times. On such occasions as the latter, the
offending party must look out for himself, or he may be roughly
handled.
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 amusement. 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.
[Illustration
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 grass 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 assist with the stage properties,
just as an assistant 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 snatched 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 Fanny 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.