Animal Intelligence (Round Two)

DNA studies have identified chimpanzees as being the closest living relatives to humans.  As such, they became natural candidates to investigate their capacity for communication.  Since early projects designed to teach chimpanzees vocal communication had ended in failure, the stage was set for a new approach.  In 1967, Allen and Beatrice Gardner began what would be an extremely ambitious project: teaching American Sign Language to a young female chimpanzee named Washoe.  Through careful work, Washoe was taught over 200 signs and observers at Central Washington University (where Washoe now lives) have reported the use of signing among the various members in the chimpanzee colony to which Washoe belongs. 

Although the use of American Sign Language was intended to overcome the inherent obstacles that other forms of communication posed to chimpanzees, the comparison to our equine friend, Clever Hans was inevitable.  Herbert Terrace, a psychologist at Colombia University, began a series of experiments with a signing chimp affectionately named Nim Chimpsky (don't ask).  Although Nim learned 125 signs, Terrace concluded that he did not show any signs of the sequential use of signing that reflected human use of grammar.  Nim simply used signs to obtain a desired end, not unlike what has been observed with other animals trained though operant conditioning (or what Clever Hans had been doing).  Terrace's conclusions, which he published in his 1979 Book Nim, placed him at odds with the Gardners who challenged his findings on methodological grounds.  They considered the conditions under which Nim was taught to be too artificial and that the naturalistic setting in which Washoe and other signing chimps were raised was better suited to learning to communicate.

While critics have accused Washoe's handlers of self-deception, the researchers in the Washoe project have reported observing the chimps using signing to communicate among themselves and even teaching it to the young chimps in the colony. Ironically, Washoe herself can be said to have weighed in on the controversy when she bit off the middle finger of Karl Pribram, a prominent neuroscientist who is a vocal critic of chimpanzee communication research.  Then again, Clever Hans bit Oskar Pfungst as well (is objecting to criticism a sign of intelligence?).

Nim Chimpsky died of a heart attack in 2000 while Washoe is still at Central Washington University.   At present, the controversy continues and It still remains to be seen whether or not Clever Hans will have the last whinny.