While both animals and humans use systems of communication, the use of complex symbols and open vocal systems is unique to humans.
Name differences between human language and animal communication
Communication in both animals and humans consists of signals. Signals are sounds or gestures that have meaning to those using them.
Human communication consists of both signals and symbols. Symbols are sounds, gestures, material objects, or written words that have specific meaning to a group of people.
Key differences between human communication and that of other primates are that (1) humans have an open vocal system while other primates have a closed vocal system, and (2) humans have a larger bank of symbols to use in communication.
A sound or gesture that has meaning to those using it.
Examples of animal communication include whale songs, bee dances, and birds chirping.
All animals use some form of communication, although some animal communication is more complex than others. Animal language is any form of communication that shows similarities to human language; however, there are significant differences. Some animals use signs, signals, or sounds to communicate. Lexigrams, or figures and symbols that represent words, are commonly used by chimpanzees and baboons, while animals such as birds and whales use song to communicate among one another. Bees uses complex "dances" to convey information about location. Other animals use odors or body movements to communicate.
Communication in both animals and humans consists of signals. Signals are sounds or gestures that have some meaning to those using them. The meaning is often self-evident based on context: for example, many animals roar, growl, or groan in response to threats of danger; similarly, humans may wave their arms or scream in the event of something dangerous. These signals in these situations are designed to let others in the species know that something is wrong and the animal or human needs help.
Human communication consists of both signals and symbols. Symbols are sounds or gestures that have a specific meaning to a group of people. This meaning could be cultural, group-related, or even related between two specific people. For example, two people may create a "secret" handshake, or a group may develop a passcode that only members are aware of. Symbols, unlike signals, must be taught and learned; they are not instinctual or self-evident.
What about nonhuman primates, who share many similarities with humans? Nonhuman primates communicate in ways that are very similar to those used by humans; however, there are important differences as well. First and foremost, humans use a larger repertoire of symbols, and these symbols are substantially more complex. Second, and more importantly, nonhuman primates (and other animals who communicate with one another) have what is known as a closed vocal system: this means different sounds cannot be combined together to produce new symbols with different meanings. Humans, by contrast, have open vocal systems, which allow for combinations of symbols to create new symbols with a totally new meaning and therefore allows for an infinite number of ideas to be expressed.
Human language is also the only kind that is modality-independent; that is, it can be used across multiple channels. Verbal language is auditory, but other forms of language—writing and sign language (visual), Braille (tactile)—are possible in more complex human language systems.
One of the most famous case studies in the debate over how complex nonhuman-primate language can be is Koko the gorilla. Koko is famous for having learned over a thousand signs of "Gorilla Sign Language," a simple sign language developed to try to teach nonhuman primates complex language. Koko can respond in GSL to about two thousand words of spoken English. However, it is generally accepted that she does not use syntax or grammar, and that her use of language does not exceed that of a young human child.