The Mind of an Ape
Encyclopedia
The Mind of an Ape is a 1983 book by David and Ann James Premack. In it, the authors argue that it is possible to teach language
to (non-human) great ape
s. They write that: "We now know that someone who comprehends speech must know language, even if he or she cannot produce it."
, emeritus professor of psychology at the University of Pennsylvania, and Ann James Premack, a science writer, began teaching language to apes in 1964. Premack started his work at the Yerkes Laboratories of Primate Biology in Orange Park, Florida
, a program at the University of Florida
, continued it at the University of Missouri
, then at the University of California, Santa Barbara
and the University of Pennsylvania
.
s, were reared in a laboratory environment specifically designed to stimulate their intellect, as animals raised otherwise fail to thrive. This was in contrast to the traditional psychology lab where the animals are caged and remain in solitude. The apes were:
program differed from that of a separate research program in which other chimpanzees were raised in a human family in parallel with human babies, and taught words.
Eventually, the chimpanzees might get to a two-year-old human's list of words, but no further. Vicki (chimpanzee)
was eventually trained to speak four words.
The experiments with those chimpanzees did not demonstrate the existence of the faculties shown by Sarah (chimpanzee)
discussed below, in her command of a language, for example. In other experiments, other chimpanzees have been taught American Sign Language
, notably Washoe (chimpanzee)
,.
Washoe could use 68 gestures after three years of training, eventually getting to 150 gestures. However, Nim (chimpanzee)
,
trained in American Sign Language
, was found to demonstrate no forms with grammar, his linguistic productions being sets of gestures in no particular order. Koko (gorilla)
and Chantek (orangutan)
were also trained in American Sign Language. See also Kanzi
's 400-word vocabulary of spontaneous productions as of 2005.
consisted of a series of colored plastic tokens, which the chimpanzees could manipulate and stick to a magnetic board. Each token stood for a word which was never spoken in the chimpanzee's presence. Sarah began her language training in 1967 at age 5, beginning with food exchanges, in order to establish a social exchange with the instructor. The Premacks note that the chimpanzees gave food reluctantly and unwillingly, far preferring to receive food. In a series of experiments, Premack was able to train Sarah, Elizabeth, and Peony to parse sentences:
which might result in Peony touching the trainer's nose.
The tokens did not resemble the objects; an apple was symbolized by a blue triangle token. The chimpanzee Elizabeth would be symbolized by a decorated E token, a copy of which would dangle from a necklace around her neck. The trainer would also wear a corresponding token, as would other investigators whom the chimpanzee would have to name in the formation of the target sentence
. It took Sarah, Elizabeth, and Peony each hundreds of trials to first form an association between the tokens and the objects. Sarah in particular was trained in the token manipulations for eighteen months.
Sarah was able to learn imperative sentences with a grammar,
in which the trainer allowed her to take the bread and jam, and also negative sentences
in which the trainer restrained her from taking the cracker and honey, which taught Sarah to suppress her impulse to take the negated object. In particular, the noun had to be at the beginning and the verb had to be at the end of the production, or else the trainer would not respond to Sarah's ungrammatical sentence. After hundreds of trials, Sarah could reliably produce the grammatical form
s in the form of a question token "?" which she could answer by selecting a resolving token. However Sarah was never able to ask questions by manipulating the "?" token. The question "What is the color of apple?"
would be answered with the token for 'red' (a gray curved token).
She learned
and
She was tested with
which she answered correctly with
Finally, with the trainer placing a ripe fig on the table, and the tokens fig token1, crackerjack token2, give, Mary, Sarah, orange, banana, Sarah produced the new sentence
and with the trainer placing a crackerjack on the table, Sarah produced the new sentence
and to express judgement
s. In these trials
, problems were formulated by videotape
d situations involving an actor, both friendly and unfriendly. With no training, and with observation of the laboratory only, Sarah was able to select answers requiring judgement, based on her experiences in the laboratory, such as the fact that a light cord had to be plugged in to solve some problems. Sarah was able to select proposed solutions for resolving the situations.
Sarah was most accurate on judgements of sameness, less so on similarity, and least accurate on judgements of difference. Human children were then tested with the same protocols, using speech. Young children passed the tests on number but failed on tests measuring conservation of liquid and solid. Five to six-year-old children passed the tests on conservation of liquid and solid, suggesting a similar process for the cognition of measurement of conservation of liquid and solid, between ape and human.
In this sentence, if Sarah were to take the apple
, then Mary, the trainer, would give her the chocolate
. But if Sarah were to take the banana
, then Mary would not give her the chocolate.
, unless the map was an exact-scale replica
of the mission situation.
Washoe (chimpanzee)
,
spontaneously signed, in contrast to Nim (chimpanzee)
.
However, Kanzi (bonobo)
,
at age 30 months demonstrated spontaneous production
of gestures and keyboard presses to ask for desired objects or events, and to name items in response to queries from the trainer. Kanzi had not been trained in producing communications. Apparently he learned this while playing in the training room while his adoptive mother Matata (bonobo) was being trained to use gestures and keyboard presses ("Lexigrams")
.
The spontaneous productions by Kanzi occurred in the absence of Matata. Kanzi can currently produce 400 words and recognize 500.
Vauclair notes that chimpanzees will become distressed in the absence of their favorite companion
Language
Language may refer either to the specifically human capacity for acquiring and using complex systems of communication, or to a specific instance of such a system of complex communication...
to (non-human) great ape
Hominidae
The Hominidae or include them .), as the term is used here, form a taxonomic family, including four extant genera: chimpanzees , gorillas , humans , and orangutans ....
s. They write that: "We now know that someone who comprehends speech must know language, even if he or she cannot produce it."
The authors
David PremackDavid Premack
David Premack is currently emeritus professor of psychology at the University of Pennsylvania. He was educated at the University of Minnesota when logical positivism was in full bloom. The departments of Psychology and Philosophy were closely allied...
, emeritus professor of psychology at the University of Pennsylvania, and Ann James Premack, a science writer, began teaching language to apes in 1964. Premack started his work at the Yerkes Laboratories of Primate Biology in Orange Park, Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
, a program at the University of Florida
University of Florida
The University of Florida is an American public land-grant, sea-grant, and space-grant research university located on a campus in Gainesville, Florida. The university traces its historical origins to 1853, and has operated continuously on its present Gainesville campus since September 1906...
, continued it at the University of Missouri
University of Missouri
The University of Missouri System is a state university system providing centralized administration for four universities, a health care system, an extension program, five research and technology parks, and a publishing press. More than 64,000 students are currently enrolled at its four campuses...
, then at the University of California, Santa Barbara
University of California, Santa Barbara
The University of California, Santa Barbara, commonly known as UCSB or UC Santa Barbara, is a public research university and one of the 10 general campuses of the University of California system. The main campus is located on a site in Goleta, California, from Santa Barbara and northwest of Los...
and the University of Pennsylvania
University of Pennsylvania
The University of Pennsylvania is a private, Ivy League university located in Philadelphia, Pennsylvania, United States. Penn is the fourth-oldest institution of higher education in the United States,Penn is the fourth-oldest using the founding dates claimed by each institution...
.
The apes
The subjects of the program, nine chimpanzeeChimpanzee
Chimpanzee, sometimes colloquially chimp, is the common name for the two extant species of ape in the genus Pan. The Congo River forms the boundary between the native habitat of the two species:...
s, were reared in a laboratory environment specifically designed to stimulate their intellect, as animals raised otherwise fail to thrive. This was in contrast to the traditional psychology lab where the animals are caged and remain in solitude. The apes were:
- SarahSarah (chimpanzee)Sarah is an enculturated research chimpanzee whose cognitive skills are documented in The Mind of an Ape, by David Premack and Ann James Premack . Sarah was one of nine chimpanzees in David Premack's psychology laboratory in Pennsylvania. Sarah was born in Africa in 1962. She first worked in...
, born in 1962, demonstrated use of an invented language - Gussie, failed to learn any words
- Elizabeth, trained in the language
- Peony, trained in the language
- Walnut, a late arrival, trained in the language, but failed to learn any words.
- Jessie, 1975 control, not trained in the language, but demonstrated pointing
- Sadie, 1975 control, not trained in the language, but demonstrated pointing
- Bert, 1975 control, not trained in the language, but demonstrated pointing
- Luvie, 1975 control, not trained in the language, but demonstrated pointing
Language suitable for an ape
The language designed by Premack for an ape was not verbal; Premack's chimpanzeeChimpanzee
Chimpanzee, sometimes colloquially chimp, is the common name for the two extant species of ape in the genus Pan. The Congo River forms the boundary between the native habitat of the two species:...
program differed from that of a separate research program in which other chimpanzees were raised in a human family in parallel with human babies, and taught words.
Eventually, the chimpanzees might get to a two-year-old human's list of words, but no further. Vicki (chimpanzee)
Vicki (chimpanzee)
Viki was the subject of one of the first experiments in ape language. Viki was raised by Keith and Catherine Hayes in the same manner as a human infant, to see if she could learn human words. She was given speech therapy, which involved the Hayeses manipulating her lower jaw...
was eventually trained to speak four words.
The experiments with those chimpanzees did not demonstrate the existence of the faculties shown by Sarah (chimpanzee)
Sarah (chimpanzee)
Sarah is an enculturated research chimpanzee whose cognitive skills are documented in The Mind of an Ape, by David Premack and Ann James Premack . Sarah was one of nine chimpanzees in David Premack's psychology laboratory in Pennsylvania. Sarah was born in Africa in 1962. She first worked in...
discussed below, in her command of a language, for example. In other experiments, other chimpanzees have been taught American Sign Language
American Sign Language
American Sign Language, or ASL, for a time also called Ameslan, is the dominant sign language of Deaf Americans, including deaf communities in the United States, in the English-speaking parts of Canada, and in some regions of Mexico...
, notably Washoe (chimpanzee)
Washoe (chimpanzee)
Washoe was a chimpanzee who was the first non-human to learn to communicate using American Sign Language, as part of a research experiment on animal language acquisition....
,.
Washoe could use 68 gestures after three years of training, eventually getting to 150 gestures. However, Nim (chimpanzee)
,
trained in American Sign Language
American Sign Language
American Sign Language, or ASL, for a time also called Ameslan, is the dominant sign language of Deaf Americans, including deaf communities in the United States, in the English-speaking parts of Canada, and in some regions of Mexico...
, was found to demonstrate no forms with grammar, his linguistic productions being sets of gestures in no particular order. Koko (gorilla)
Koko (gorilla)
Koko is a female western lowland gorilla who, according to Francine "Penny" Patterson, is able to understand more than 1,000 signs based on American Sign Language, and understand approximately 2,000 words of spoken English....
and Chantek (orangutan)
were also trained in American Sign Language. See also Kanzi
Kanzi
Kanzi , also known by the lexigram , is a male bonobo who has been featured in several studies on great ape language. According to Sue Savage-Rumbaugh, a primatologist who has studied the bonobo throughout her life, Kanzi has exhibited advanced linguistic aptitude.- Biography :Born to Lorel and...
's 400-word vocabulary of spontaneous productions as of 2005.
The language tokens
The languageLanguage
Language may refer either to the specifically human capacity for acquiring and using complex systems of communication, or to a specific instance of such a system of complex communication...
consisted of a series of colored plastic tokens, which the chimpanzees could manipulate and stick to a magnetic board. Each token stood for a word which was never spoken in the chimpanzee's presence. Sarah began her language training in 1967 at age 5, beginning with food exchanges, in order to establish a social exchange with the instructor. The Premacks note that the chimpanzees gave food reluctantly and unwillingly, far preferring to receive food. In a series of experiments, Premack was able to train Sarah, Elizabeth, and Peony to parse sentences:
- Peony nose touch
which might result in Peony touching the trainer's nose.
The tokens did not resemble the objects; an apple was symbolized by a blue triangle token. The chimpanzee Elizabeth would be symbolized by a decorated E token, a copy of which would dangle from a necklace around her neck. The trainer would also wear a corresponding token, as would other investigators whom the chimpanzee would have to name in the formation of the target sentence
Sentence (linguistics)
In the field of linguistics, a sentence is an expression in natural language, and often defined to indicate a grammatical unit consisting of one or more words that generally bear minimal syntactic relation to the words that precede or follow it...
. It took Sarah, Elizabeth, and Peony each hundreds of trials to first form an association between the tokens and the objects. Sarah in particular was trained in the token manipulations for eighteen months.
Sarah was able to learn imperative sentences with a grammar,
- Sarah jam bread take
in which the trainer allowed her to take the bread and jam, and also negative sentences
- No Sarah honey cracker take
in which the trainer restrained her from taking the cracker and honey, which taught Sarah to suppress her impulse to take the negated object. In particular, the noun had to be at the beginning and the verb had to be at the end of the production, or else the trainer would not respond to Sarah's ungrammatical sentence. After hundreds of trials, Sarah could reliably produce the grammatical form
- Mary give apple Sarah
List of tokens
- Nouns
- Sarah
- Mary (Mary Morgan, Sarah's favorite trainer)
- pail
- dish
- chocolate
- apple
- banana
- apricot
- raisin
- Verbs
- is
- give
- take
- insert
- wash
- Concepts/Conditionals
- same
- different
- no-not
- name-of
- color-of
- "?"QuestionA question may be either a linguistic expression used to make a request for information, or else the request itself made by such an expression. This information may be provided with an answer....
- if-thenCausalityCausality is the relationship between an event and a second event , where the second event is understood as a consequence of the first....
- Colors (tokens were not colored with the corresponding colors)
- red
- yellow
- brown
- green
Questions
Sarah was also able to answer questionQuestion
A question may be either a linguistic expression used to make a request for information, or else the request itself made by such an expression. This information may be provided with an answer....
s in the form of a question token "?" which she could answer by selecting a resolving token. However Sarah was never able to ask questions by manipulating the "?" token. The question "What is the color of apple?"
- "?" color of apple (blue triangle)
would be answered with the token for 'red' (a gray curved token).
New symbols
Premack was able to demonstrate that Sarah could understand how to decode a symbol stream after training. First she had to learn the token "name-of" and then learn that some new, but real objects had the name-of fig token1 and crackerjack token2.She learned
- Real fig name-of fig token1
and
- Real crackerjack name-of crackerjack token2.
She was tested with
- fig token1 "?" Real crackerjack
which she answered correctly with
- fig token1 Not name-of Real crackerjack
Finally, with the trainer placing a ripe fig on the table, and the tokens fig token1, crackerjack token2, give, Mary, Sarah, orange, banana, Sarah produced the new sentence
- Mary give fig token1 Sarah
and with the trainer placing a crackerjack on the table, Sarah produced the new sentence
- Mary give crackerjack token2 Sarah
Other concepts
Sarah, Peony, and Elizabeth were able to respond to and formulate analogiesAnalogy
Analogy is a cognitive process of transferring information or meaning from a particular subject to another particular subject , and a linguistic expression corresponding to such a process...
and to express judgement
Judgement
Judgment is the evaluation of evidence in the making of a decision. The term has three distinct uses:* Informal - Opinions expressed as facts....
s. In these trials
Experiment
An experiment is a methodical procedure carried out with the goal of verifying, falsifying, or establishing the validity of a hypothesis. Experiments vary greatly in their goal and scale, but always rely on repeatable procedure and logical analysis of the results...
, problems were formulated by videotape
Videotape
A videotape is a recording of images and sounds on to magnetic tape as opposed to film stock or random access digital media. Videotapes are also used for storing scientific or medical data, such as the data produced by an electrocardiogram...
d situations involving an actor, both friendly and unfriendly. With no training, and with observation of the laboratory only, Sarah was able to select answers requiring judgement, based on her experiences in the laboratory, such as the fact that a light cord had to be plugged in to solve some problems. Sarah was able to select proposed solutions for resolving the situations.
Sarah was most accurate on judgements of sameness, less so on similarity, and least accurate on judgements of difference. Human children were then tested with the same protocols, using speech. Young children passed the tests on number but failed on tests measuring conservation of liquid and solid. Five to six-year-old children passed the tests on conservation of liquid and solid, suggesting a similar process for the cognition of measurement of conservation of liquid and solid, between ape and human.
The Conditional statement
Sarah was able to parse the following sentence in a way to give her the most reward:- Sarah take banana if-thenConditional statementIn computer science, conditional statements, conditional expressions and conditional constructs are features of a programming language which perform different computations or actions depending on whether a programmer-specified boolean condition evaluates to true or false...
Mary no give chocolate
In this sentence, if Sarah were to take the apple
Apple
The apple is the pomaceous fruit of the apple tree, species Malus domestica in the rose family . It is one of the most widely cultivated tree fruits, and the most widely known of the many members of genus Malus that are used by humans. Apple grow on small, deciduous trees that blossom in the spring...
, then Mary, the trainer, would give her the chocolate
Chocolate
Chocolate is a raw or processed food produced from the seed of the tropical Theobroma cacao tree. Cacao has been cultivated for at least three millennia in Mexico, Central and South America. Its earliest documented use is around 1100 BC...
. But if Sarah were to take the banana
Banana
Banana is the common name for herbaceous plants of the genus Musa and for the fruit they produce. Bananas come in a variety of sizes and colors when ripe, including yellow, purple, and red....
, then Mary would not give her the chocolate.
Pointing
The chimpanzees do not spontaneously point outside of the psychological laboratory. The control chimpanzees, who were not trained in the language, could all point in order to communicate with the trainers.Mappings and other representations
The chimpanzees of Premack's laboratory were not able to navigate given training on a mapMap
A map is a visual representation of an area—a symbolic depiction highlighting relationships between elements of that space such as objects, regions, and themes....
, unless the map was an exact-scale replica
Scale model
A scale model is a physical model, a representation or copy of an object that is larger or smaller than the actual size of the object, which seeks to maintain the relative proportions of the physical size of the original object. Very often the scale model is used as a guide to making the object in...
of the mission situation.
Spontaneous productions
Not all individuals in a given species have equivalent capabilities to produce spontaneous communications.Washoe (chimpanzee)
Washoe (chimpanzee)
Washoe was a chimpanzee who was the first non-human to learn to communicate using American Sign Language, as part of a research experiment on animal language acquisition....
,
spontaneously signed, in contrast to Nim (chimpanzee)
.
However, Kanzi (bonobo)
,
at age 30 months demonstrated spontaneous production
Production, costs, and pricing
The following outline is provided as an overview of and topical guide to industrial organization:Industrial organization – describes the behavior of firms in the marketplace with regard to production, pricing, employment and other decisions...
of gestures and keyboard presses to ask for desired objects or events, and to name items in response to queries from the trainer. Kanzi had not been trained in producing communications. Apparently he learned this while playing in the training room while his adoptive mother Matata (bonobo) was being trained to use gestures and keyboard presses ("Lexigrams")
.
The spontaneous productions by Kanzi occurred in the absence of Matata. Kanzi can currently produce 400 words and recognize 500.
Natural gestures
The Premacks note that chimpanzees use some gestures with each other, which the trainers use to communicate with both the language-trained chimpanzees and the control chimpanzees.- Requests for food
- hand cupped, palm upward, for a chimpanzee to place food in.
- extruding lips in supplication
- Appeasement
- One chimpanzee, trembling, hugged Premack at the beginning of his career, as if to appease him at the time of displaying outrage
- Grooming
- Eating
- Greeting
Other personal traits
The Premacks stated that the chimpanzees had specific traits, such as favorite trainers, and that some chimpanzees, such as Gussie, seemed more fearful than the others. As previously noted, the Premacks noticed that Jessie seemed to be the brightest of the nine chimpanzee subjects. For example, she did not hesitate to unmask a masked researcher, which none of the other chimpanzees attempted. It is clear that the Premacks attempted to provide a humane, supportive environment for the chimpanzees.Vauclair notes that chimpanzees will become distressed in the absence of their favorite companion
See also
- Primate cognitionPrimate cognitionPrimate cognition is the study of the cognitive abilities of non-human primates. Humans are also primates but, traditionally, humans have been thought to be different from other animals...
- Thomas NagelThomas NagelThomas Nagel is an American philosopher, currently University Professor of Philosophy and Law at New York University, where he has taught since 1980. His main areas of philosophical interest are philosophy of mind, political philosophy and ethics...
(seminal paper, 'What is it like to be a bat?') - Animal cognitionAnimal cognitionAnimal cognition is the title given to the study of the mental capacities of non-human animals. It has developed out of comparative psychology, but has also been strongly influenced by the approach of ethology, behavioral ecology, and evolutionary psychology...