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Primate Signing:
Also see: "Animals and Signing"
Also see: "Signing with Gorillas"

Brian James


Language: Finding The Link
            The scientific community and especially those in the realm of anthropology have long studied the world of primate evolution and how it fits into the development of human culture. There are many avenues that researchers have explored in completing the picture of human evolution including skeletal morphology, tool technology, food processing and methods of hunting and agriculture. All of these aspects are easily understood within the range of a few million years since the first evidence of bipedalism in early hominids. Conversely, little is understood about our living primate counterparts in terms of how their culture represents previous stages of human development, there is one area of study that has shed light and understanding on this dilemma, language. More specifically it is the use of American Sign Language as a catalyst in understanding how language originates and helping to bridge the gap in human evolution.
            It is fairly well know that chimpanzees remain our closest living relatives in terms of genetic similarity. Apes in general share many characteristics with modern humans including a higher intelligence than most other mammals and an ever increasing and better understood culture including tools and family systems. However, one thing that modern apes do not share with humans is the area of the brain that is capable of producing speech called Broca’s area, instead there are similar, less complex areas located in the primate brain that may be linked to simple communication (sci/tech news staff 2006). However in anthropology it is recognized that speech and language can mean two succinctly different things. This has become increasingly apparent in primate use of ASL to convey thought and observances. Recently, and as far back as the early sixties there have been two cases that have been expressively interesting to the scientific community. The first being the case of a chimpanzee named Washoe who had been reported to have been able to use 250 signs and the second being a young gorilla named Koko who has been reported to use 1,000 different signs.
                     As part of a research experiment on animal language acquisition, Washoe developed a modest ability to communicate with humans using ASL. Washoe had lived at Central Washington University since 1980. Washoe was taught ASL based on a method that used rewarding the signs when they were correct.  When Washoe would spontaneously make a gesture that in some way resembled an ASL sign, the scientists would shape the gesture by encouraging and rewarding variations of that gesture until it became a true ASL sign. Washoe caught on quickly to the idea that the ASL sign for MORE could be used to get more of anything, including food, games, and books. In this way, the chimpanzee showed the ability to spontaneously generalize an abstract concept such as "MORE" to a variety of contexts in which training had not occurred. There however has been some controversy in the scientific community surrounding the experiment with Washoe. It is not believed that her cognition of the signs is true. It is claimed that Washoe learned many signs as a trick, which many other animals can do to various extents (Gardner 1989).
            Koko much like Washoe was taught ASL by researchers however the method of teaching is much different. Koko was exposed to ASL signs from the age of one and has developed around 1,000 independent signs. Koko uses the language freely and in novel ways, even when there is no foreseeable gratification (Steinberg 2000). Koko has been documented inventing new signs to communicate novel thoughts. For example, the primary researcher to work with Koko, Dr. Francine Patterson, asserts that nobody taught Koko the word for "ring", therefore to refer to it she combined the words "finger" and "bracelet", hence "finger-bracelet". Similarly, she invented "drink-fruit" (melon), "water-bird" (swan) and "animal-person" (gorilla) (Candland 1993).
            With the advances in the study of primate language development we can begin to complete the complex puzzle of human evolution. ASL has become the gate way to knowledge in the field and the first human language to be used by non-human species. Anthropology has been able to develop methods and standardized practices to incorporate ASL into modern primatology.



Candland, Douglas K (1993) Feral Children and Clever Animals: Reflections on Human Nature. Oxford, England. Oxford University Press

Gardner, R. Allen, Gardner, Beatrix T., Van Cantfort, Thomas E. (1989). Teaching Sign Language to Chimpanzees. Albany, New York. SUNY Press

Sci/Tech News Staff (2006, July 24) Shared Ancestor to Humans and Present-Day Non-Human
Primates May Be Linchpin In Evolution of Language. Softpedia. SoftNews NET SRL. Retrieved 24, March 24, 2008:

Steinberg, Danny D., Sciarini, Natalia V. (2000).  An Introduction to Psycholinguistics. London, England. Pearson Longman


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