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Gardner & Gardner (1969)
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1. How do animals communicate?2. What is so special about human language?
3. Early attempts
4. Gardner & Gardner5. Evaluation
6. Subsequent studies
7. Further criticisms
8. Latest developments
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Bird songs Bee dance Whale songs Primate vocal calls
Used in certain contexts: mating, danger of predation etc Associated with basic brain structures
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Chomsky (1959)
Structured and governed by principles Used in a specific manner Governed by special language centres
Pinker (1994)
Infinite Digital Compositional
Aitchison (1983) identifies 4 characteristics which are unique tohuman language
Semanticity Displacement Creativity Structure-dependence
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Teaching vocal language to chimpanzees, adoptedand raised in families (cross-fostering)
Kellog Kellog (1933)
Gua (chimpanzee)- never produced any single word andseemed to understand only a few
Hayes Hayes (1951)
Viki (chimpanzee)- mama, papa, cup, up.
Chimpanzee’s vocal apparatus not suited for speech.
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Design
Case study of an enculturated infant female chimp, WashoePhase one: extending over 22 monthsASL training (pictorial sign language, with grammar and
syntax)
Training by operant conditioning (positive reinforcementmainly)
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Scoring
When Washoe learned a new sign, it was onlyafter three different observers noted it ashaving occurred in an appropriate context
and spontaneously, the sign was added to a“checklist”
A reported frequency of at least 1 appropriate
and spontaneous occurrence each day over aperiod of 15 consecutive days was taken asthe criterion of acquisition
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Outcome
Within 22 months of training, Washoe learned 30signs and used them reliably Come-gimme, more, up, hurry, toothbrush … Hurt, sorry, funny …
Rate of vocabulary acquisition was accelerating Spontaneous transfer (e.g. flower for various
smells) Used rudimentary combinations of signs,
apparently also novel ones (e.g. gimme tickle,listen dog )
Trained her adopted son, Loulis, in ASL
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Strengths
Decision to teach ASL- breakthrough
Very intensive training schedule, using simple
operant conditioning Care for the welfare of the animal
Multiple observers, standard criteria for judging whether Washoe learned a new sign
or not Long-term study, extended to include
Washoe’s adopted children
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Crucial question:
s it language or not
Semanticity? Creativity? Displacement? Structure-dependence?
Can you explain the acquisition of „ape language” byother means?
Note that: In humans, babies are not explicitly taught by their parents
to speak, yet within a few years of life they master languagecompletely
Chimpanzees don’t develop language in nature
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Premack (1971)
Sarah, communication with small plastic symbols
no claims for proper language
Patterson (1978, 1980)
Koko (gorilla), taught ASL; allegedly quitesophisticated language
„Language is no longer a uniquely human faculty”
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Terrace (1979)
Nim Chimpsky, taught ASL; rigorous methodology Initially reported success
Upon evaluation, concluded that what Nim learnedwas not language No grasp of grammar
MLU constant
Imitative in nature
No „conversation”
A fierce critic of ape-language research
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Noam Chomsky
In humans, language cannot possibly belearned through operant conditioning.
LAD
Steven Pinker
Signs or gestures? Problems with interpretation
Average length of utterrance Usage
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Savage-Rumbaugh
Kanzi, a bonobo chimp
Lexigrams
Learned language via observation, notdeliberate training
Focus on understanding
Rudimentary grammar
Invents some protogrammatical rules Language ability of a 2.5-year-old child
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If chimpanzees cannot learn language
Why is that? What specific prerequisite dothey lack? Innate language module?
Theory of Mind?
Perhaps training methods were inadequate
Perhaps chimpanzees need a longer time toacquire language
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If chimpanzees can learn language
Then language is not a uniquely human capacityanymore
The difference between animals and humansmust be redefined
Research on ToM in primates needs to bereconsidered
The evolution of language must be rewritten Language evolved long time ago, in an ancestor common to
chimps and humans? But why wouldn’t chimpanzees use language in
the wild?
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Key reading
Gardner, R.A. & Gardner, B.T. (1969). Teaching sign language to achimpanzee. Science, 165, 664-72.
Additional readings
Gibbons, A. (1991). Deja vu all over again: chimp-language wars. Science,251, 1561-1562.
Terrace, H.S., Pettito, L.A., Sanders, R.J. & Bever, T.G. (1979). Can an apecreate a sentence? Science, 206, 891-902.
Washoe „Obituary” in the New York Timeshttp://www.nytimes.com/2007/11/01/science/01chimp.html?_r=1&em&ex=1194148800&en=953723ba97c73b53&ei=5087%0A&oref=slogin
ASL video dictionaryhttp://commtechlab.msu.edu/sites/aslweb/browser.htm
I just couldn’t resits… A very non-scientific demonstration of the limits ofhow much we can attribute to primates:http://www.youtube.com/watch?v=qiiUrAS9BL4
http://www.nytimes.com/2007/11/01/science/01chimp.html?_r=1&em&ex=1194148800&en=953723ba97c73b53&ei=5087&oref=sloginhttp://www.nytimes.com/2007/11/01/science/01chimp.html?_r=1&em&ex=1194148800&en=953723ba97c73b53&ei=5087&oref=sloginhttp://www.nytimes.com/2007/11/01/science/01chimp.html?_r=1&em&ex=1194148800&en=953723ba97c73b53&ei=5087&oref=sloginhttp://www.nytimes.com/2007/11/01/science/01chimp.html?_r=1&em&ex=1194148800&en=953723ba97c73b53&ei=5087&oref=sloginhttp://commtechlab.msu.edu/sites/aslweb/browser.htmhttp://commtechlab.msu.edu/sites/aslweb/browser.htmhttp://www.youtube.com/watch?v=qiiUrAS9BL4http://www.youtube.com/watch?v=qiiUrAS9BL4http://www.youtube.com/watch?v=qiiUrAS9BL4http://commtechlab.msu.edu/sites/aslweb/browser.htmhttp://www.nytimes.com/2007/11/01/science/01chimp.html?_r=1&em&ex=1194148800&en=953723ba97c73b53&ei=5087&oref=sloginhttp://www.nytimes.com/2007/11/01/science/01chimp.html?_r=1&em&ex=1194148800&en=953723ba97c73b53&ei=5087&oref=slogin