"The Behavior of Chimpanzees"
Wild Chimpanzees:
Bibliography:
Kortlandt, Adriaan, "Chimpanzees in the Wild," "Scientific American," May, 1962
Pfeiffer, John E., "Chimpanzees: Man's Closest Relatives," in "The Emergence of Man," New York: Harper & Row, Publishers, 1972
Kellogg, Winthrop N., "Communication and Language in the Home-raised Chimpanzee," "Science," Oct. 25, 1968
Menzel, Emil W., and Halperin, Stewart, "Purposive Behavior as a Basis for Objective Communication Between Chimpanzees," "Science," Aug. 22, 1975
Linden, Eugene, "The Chimpanzee in the Temple of Language." in "Apes, Men, and Language," New York: Saturday Review Press/E.P. Dutton & Co., 1970
Bernstein, Irwin S., "Chimpanzees," "Encyclopedia Americana," Vol. 6, New York: Americana Press, 1976
-----------, "Individuality in Chimpanzee Behavior," "Science," Aug. 3, 1956
Wild Chimpanzees:
If you were to watch wild chimpanzees for a few days, the main impression you would receive is one of quietness and cautiousness. When Adriaan Kortlandt observed them in the Eastern Congo, he had to conceal himself very well, high in a tree, to watch them without disturbance.
Before the chimpanzees, Adriaan saw, entered a clearing, they would peep out cautiously through the leaves and listen to make sure no one was around. The males he saw emerged first, walking upright to get a better view of the clearing. When they were safe, the males started a deafening and wild intimidation display. They stamped and smacked the ground and trees. They chased one another shrieking, screaming, and occasionally throwing and brandishing branches around. But, the chimpanzees never hit one another for it is very rare for them to fight among themselves.
The female chimpanzees, especially the mothers, were very shy and silent. The maternal behavior of the mother is a very protective one. Up to four years of age, the children were usually carried by the mother whether it was a long or short trip. Puberty, for chimpanzees in captivity, is not until eight or nine, and the child is not let out of sight until puberty occurs. Although they were closely watched, the young chimpanzees led a perfect life. They were constantly pampered, allowed to do almost anything they pleased, and hand-fed to six or seven years of age. Many times, one of the youngsters was seen smacking an adult male on the rump and running away without arousing any anger from the male.
Old chimpanzees of over forty received similar treatment. To communicate they often used gestures, for the chimpanzees infrequently made any noise except during an emergency or the intimidation displays. The reason for such quietness is because of the inherent dangers of the forest.
The chimpanzees liked to have variety in their life. They did this by varying their paths, gaits, and anything they could differ. One chimpanzee watched a brilliant sunset for fifteen minutes instead of gathering dinner.
There were two groups of chimpanzees that were distinguishable; the sexual group and the nursery group. The sexual group contained largely adult males, childless females, and they often included a few mothers and children. The nursery group consisted of a few adult males, the children, and their mothers. The nursery group usually contained five or more less than the other, which usually had more than twenty. Intermingling did occur to some extent.
Rivers of any depth separate the different "races" of chimpanzees because they do not swim.
Fifteen per cent of the distance traveled by the chimpanzee was on two legs. The rest was on three and four. Another reason why they use a two-legged gait, other than that they get a better view, is for variety.
Chimpanzees in Captivity:
The chimpanzee is good at imitating activities and movements it sees performed, but not as good as the youngsters. Unlike the parrot it cannot imitate noises and sounds very well.
The infant chimpanzee shows a strong innate attachment to its physical surroundings. Up to the age of three its development of physical features are much more rapid than those of an "infant,' and its "mental age" is only slightly behind that of a human child. Many childrens' preschool developmental tests are passed by the infant chimp.
An experiment by the Hayeses successfully taught their chimpanzee, Vicki, to say "mama" by manipulating her lips as she said it. Later she learned the words "papa" and "cup" more quickly. These three words that Vicki said is the most that any chimpanzee has ever been able to say.
The experiment that the Kelloggs performed had their year old chimpanzee, Gua, competing with a human control. The experiment was to see how many commands they could respond to correctly. The commands ranged from simple ones like "No, no" to ones like "Don't put that in your mouth" and "Go to mama." Gua was ahead in the first four months of testing, but in the next five months, the human child surpassed Gua in comprehension. In the nine months of study, the chimpanzee lost by ten with fifty-eight specific responses.
Some of the behavior patterns of Gua, such as removing a bib from her neck, which means "finished eating," are childlike. Another example of this would be when Gua pushed her cup away, meaning "enough."
One thing you can tell about chimpanzees, by watching them at play, making up their minds, choosing fruit, expressing their feelings, and when they do many other things is that they are man's closest relatives. (Note: my belief now is in the theory of "Creation.")
Before the chimpanzees, Adriaan saw, entered a clearing, they would peep out cautiously through the leaves and listen to make sure no one was around. The males he saw emerged first, walking upright to get a better view of the clearing. When they were safe, the males started a deafening and wild intimidation display. They stamped and smacked the ground and trees. They chased one another shrieking, screaming, and occasionally throwing and brandishing branches around. But, the chimpanzees never hit one another for it is very rare for them to fight among themselves.
The female chimpanzees, especially the mothers, were very shy and silent. The maternal behavior of the mother is a very protective one. Up to four years of age, the children were usually carried by the mother whether it was a long or short trip. Puberty, for chimpanzees in captivity, is not until eight or nine, and the child is not let out of sight until puberty occurs. Although they were closely watched, the young chimpanzees led a perfect life. They were constantly pampered, allowed to do almost anything they pleased, and hand-fed to six or seven years of age. Many times, one of the youngsters was seen smacking an adult male on the rump and running away without arousing any anger from the male.
Old chimpanzees of over forty received similar treatment. To communicate they often used gestures, for the chimpanzees infrequently made any noise except during an emergency or the intimidation displays. The reason for such quietness is because of the inherent dangers of the forest.
The chimpanzees liked to have variety in their life. They did this by varying their paths, gaits, and anything they could differ. One chimpanzee watched a brilliant sunset for fifteen minutes instead of gathering dinner.
There were two groups of chimpanzees that were distinguishable; the sexual group and the nursery group. The sexual group contained largely adult males, childless females, and they often included a few mothers and children. The nursery group consisted of a few adult males, the children, and their mothers. The nursery group usually contained five or more less than the other, which usually had more than twenty. Intermingling did occur to some extent.
Rivers of any depth separate the different "races" of chimpanzees because they do not swim.
Fifteen per cent of the distance traveled by the chimpanzee was on two legs. The rest was on three and four. Another reason why they use a two-legged gait, other than that they get a better view, is for variety.
Chimpanzees in Captivity:
The chimpanzee is good at imitating activities and movements it sees performed, but not as good as the youngsters. Unlike the parrot it cannot imitate noises and sounds very well.
The infant chimpanzee shows a strong innate attachment to its physical surroundings. Up to the age of three its development of physical features are much more rapid than those of an "infant,' and its "mental age" is only slightly behind that of a human child. Many childrens' preschool developmental tests are passed by the infant chimp.
An experiment by the Hayeses successfully taught their chimpanzee, Vicki, to say "mama" by manipulating her lips as she said it. Later she learned the words "papa" and "cup" more quickly. These three words that Vicki said is the most that any chimpanzee has ever been able to say.
The experiment that the Kelloggs performed had their year old chimpanzee, Gua, competing with a human control. The experiment was to see how many commands they could respond to correctly. The commands ranged from simple ones like "No, no" to ones like "Don't put that in your mouth" and "Go to mama." Gua was ahead in the first four months of testing, but in the next five months, the human child surpassed Gua in comprehension. In the nine months of study, the chimpanzee lost by ten with fifty-eight specific responses.
Some of the behavior patterns of Gua, such as removing a bib from her neck, which means "finished eating," are childlike. Another example of this would be when Gua pushed her cup away, meaning "enough."
One thing you can tell about chimpanzees, by watching them at play, making up their minds, choosing fruit, expressing their feelings, and when they do many other things is that they are man's closest relatives. (Note: my belief now is in the theory of "Creation.")
Bibliography:
Kortlandt, Adriaan, "Chimpanzees in the Wild," "Scientific American," May, 1962
Pfeiffer, John E., "Chimpanzees: Man's Closest Relatives," in "The Emergence of Man," New York: Harper & Row, Publishers, 1972
Kellogg, Winthrop N., "Communication and Language in the Home-raised Chimpanzee," "Science," Oct. 25, 1968
Menzel, Emil W., and Halperin, Stewart, "Purposive Behavior as a Basis for Objective Communication Between Chimpanzees," "Science," Aug. 22, 1975
Linden, Eugene, "The Chimpanzee in the Temple of Language." in "Apes, Men, and Language," New York: Saturday Review Press/E.P. Dutton & Co., 1970
Bernstein, Irwin S., "Chimpanzees," "Encyclopedia Americana," Vol. 6, New York: Americana Press, 1976
-----------, "Individuality in Chimpanzee Behavior," "Science," Aug. 3, 1956
