Can Other Animals Learn Human Language?
The short answer to this question is no, animals cannot learn human language. In order to answer this question, one must distinguish between human language and other forms of communication. Language is a creative and infinite system. Many other animals have complex systems of communication. Some bees, for example, can communicate information about their food: where it is and how far, and its quantity. Several species of birds and monkeys are known to have complex signaling systems. These forms of communication are different from language in that they are very limited. Humans can talk about the past, future, or fictional events. They utter sentences that they have never seen or heard before. They have the ability to use language to alter the thoughts and ideas of other humans.
There have been many attempts to teach animals language. Usually the pupil is a primate, being a human's closest relative. One such attempt involved a chimpanzee called Nim Chimpsky after the famous linguist Noam Chomsky. While Nim was quite successful compared to many other subjects, his linguistic abilities never even reached a level comparable to the level of a four-year-old human child. He could not master syntax and his vocabulary was quite small. Many scientists theorize that the primates are not actually mastering symbolic language but rather are learning behavioral responses to their human trainers. Language is uniquely human. This is not denigrating to animals. Each species has its own communication system.
The Clever Hans controversy involved a horse that appeared to be able to do math and communicate messages by tapping his hoof. It turned out that Clever Hans could not do this when he could not see his trainer. His was a feat of perception only.
One of the most interesting examples of research on animal cognition was with an African Grey parrot named Alex (an acronym for Avian Language Experiment). Psychologist Irene Pepperberg trained Alex for two decades and he was able to acquire a vocabulary of approximately 100 words for objects, colors, shapes, and numbers in addition to some simple phrases. When asked a question, such as what color a particular object was or how many of a certain item were presented, Alex could accurately answer the question. This research provides a fascinating look at what animals might be capable of in terms of communication and language, but conclusions whether animals can actually “think” are far from confirmed.