Great ape language
These studies were controversial, with debate focused on the definition of language, the welfare of test subjects, and the anthropocentric nature of this line of inquiry.
He recruited Luella and Winthrop Niles Kellogg, scientists at Indiana University, to raise a chimp named Gua alongside their human child, Donald.
The Kelloggs noted that Gua made several distinct vocalizations to communicate different needs, and, accordingly, tried to teach her to speak English words.
The Kelloggs were building on Yerkes' assertion:It seemingly is well established that the motor mechanism of voice in this ape is adequate not only to the production of a considerable variety of sounds, but also to definite articulations similar to those of man.
After the failed efforts of teaching apes to speak, the Gardners wondered whether the issue was a motor deficiency rather than cognitive inability.
The couple had been watching film of Viki, the chimp involved in the early speech study, and noticed that she was intelligible without sound; she was making gestures with her hands as she tried to pronounce words.
[20]) It proved to be a difficult benchmark to meet, especially when it came to the vocabulary involving things not typically encountered daily (horse, pipe, hankie).
)[22] The double-blind testing apparatus was set up to avoid unconscious bias, particularly a Clever Hans effect,[14] in which humans unwittingly tip off their animal subjects through body language, facial expressions, or other means.
According to Eugene Linden, an independent journalist who focused on ape language research, she asked questions and used negatives ("no" in combination with another word).
The Gardners continued to conduct sign-language research on infant chimpanzees, using Moja, Pili, Tatu, and Dar in subsequent studies.
On one hand, researchers needed a strict, repetitive process with clinical double-blind testing for their work to be accepted as science.
In 1973, Herbert S. Terrace of Columbia University set out to improve upon the Washoe research using a chimp he named Nim Chimpsky (a pun on linguist Noam Chomsky).
Over the course of Project Nim, the infant chimp was shuttled between locations and a revolving group of roughly 60 caregivers, mostly students and volunteers, few of whom were proficient in sign language.
[32] In 1972, Francine "Penny" Patterson, inspired by a lecture she attended by Allen and Beatrix Gardner,[33] began a program to teach sign language to a lowlands gorilla named Koko.
But her well-publicized achievements ignited significant controversy among scientists, who questioned whether she was truly using a "language"[35] or simply responding to Patterson's prompts.
Sarah and two other chimpanzees, Elizabeth and Peony, in the research programs of David Premack, demonstrated the ability to produce grammatical messages of token selections.
[36] A juvenile Sumatran orangutan Aazk (named after the American Association of Zookeepers) who lived at the Roeding Park Zoo (Fresno, California) was taught by Gary L. Shapiro from 1973 to 1975 how to "read & write" with plastic children's letters, following the training techniques of David Premack.
Kanzi, a bonobo, learned to communicate with a lexigram board at first by eavesdropping on the lessons researcher Sue Savage-Rumbaugh was giving to his adoptive mother.
In 2001, Alexander Fiske-Harrison, writing in the Financial Times, observed that Kanzi was "asked by an invisible interrogator through head-phones (to avoid cueing) to identify 35 different items in 180 trials.
Many argued (in line with Terrace[31]) that the apes merely demonstrated a form of operant conditioning, similar to pigeons trained to peck buttons in a specific order.
The most significant and enduring criticism regarded the lack of evidence supporting great apes' use of syntax and grammatical sentence structure.
[42] To Irene Pepperburg, a research associate who had been working with a parrot named Alex, the conference came as a wakeup call, pushing her to avoid claims about "language" and sticking to "vocal communication.
Penny Patterson, for example, turned to PR work and children's media to raise funds to care for Koko and gorilla Michael.
Roger Fouts struggled to show results for an NIH grant tied to Washoe teaching her foster baby signs.
[45] In the 1980s, he partnered with Jane Goodall on a campaign to improve conditions for chimpanzees in NIH-funded labs, an effort that effectively alienated him from fellow scientists.
[51][52] This critique argued that isolating apes from their species and drilling them in the communication method of another (Homo sapiens) was a misguided effort to sate human curiosity, not science.
Making assumptions about ape's abilities with involuntary subjects forced to live in highly unnatural conditions was seen as not only unscientific but ethically wrong.
[54] Among primates, autonomous behaviors such as body posture, facial expressions, vocalizations and scent production have been observed to convey information to other animals, revealing emotions or alerts about potential danger.
Primatologist Tetsuro Matsuzawa proposes in his cognitive tradeoff hypothesis that humans exchanged short-term and working memory for better language skills over their evolution.
[58] Other researchers in primate cognition have found evidence of ape inquiries while noting that the structure of their queries may not look exactly like human question-asking.
