How do animal communication systems differ from humans and can primates acquire language

Language has always been considered a uniquely human characteristic form of communication; ‘mans most important cultural invention, the quintessential example of his capacity to use symbols, and a biologically unprecedented event irrevocably separating him from other animals. ‘ (Pinker 1955) The absence of language is a reflection of what information must be transferred with in the species; constrained to context, stimulus and response there is no need for grammatical accuracy or structure.

There is no doubt that some animals have methods of communication; often as unique to their species as language is to man. our ability to create and understand sentences is a direct manifestation of innate mechanisms that are uniquely human…. Only humans have the intellectual capacity to create sentences according to any grammar’. (Chomsky 1959) Verbal human communication is possible due to the make up of the human vocal trait. Speech is produced by air flow from the lungs that passes through the larynx containing the vocal cords and from there through the oral and nasal cavities, which together make up the nasal tract.

Movements of the lips and tongue create vowel sounds and consonants are constructed through various articulatory movements, which temporarily construct the path of air through the vocal tract. This is fundamental when considering why human communication systems differ from animals; we have the equipment to vocalize our needs as well as instinctive urges to do so. An interesting parallel in terms of vocalizing actions is found in birds. The bird song is verbal and functional; part learned and part generic, (similar to humans) marks territory and courts a mate.

There are also regional dialects in bird song proving it is not all generic. If we consider language synonymous with speech, and speech an essential form of communication then we will inevitably conclude that animal communication methods are basic and in some cases non existent. However, while human communication is largely verbal, animals tend to communicate through displays. Honey bees conduct a ‘waggle dance’ in a figure of eight pattern. The axis represents the direction of nectar relative to the sun and the rate of waggling represents the distance.

They are able to mobilize masses of bees and communicate distance without confusion, suggesting an effective; though non-linguistic, form of communication. There is no need for a large tapestry of language for most species of animals as there is a limited number of things an animal wants to do with, to or for another animal of it’s own kind. For example flee, attack, feed or be fed by. Groom or be groomed by, copulate and a few other examples. Generally, animals are confined by stimulus; context and response; there is very little abstract communication.

Communication systems are therefore much simpler, there is no need for grammatical structure as there is inherently in the English language. Human language is structured, meaningful, referential and interpersonal or communicative. There is a linguistic hierarchy of units; sentences are made up of phrases that in turn are constructed from words. Words are a congregation of morphemes and morphemes contain phonemes. Different combinations of phonemes can be combined to create an impressively large number of words (at least 75 000 for most students).

The complexity of the human language is bizarre but inherited and has arisen to cover an almost infinitive number of situations, emotions, and needs. Body language is an enormous and underestimated form of communication that is far easier to compare and contrast to animal behavior. Babies smile at parents while dogs roll over on to their backs to indicate trust and submission towards their owners or parents . Both are born with these reactions and come naturally regardless of nurture. Blind babies are reported to smile at the same stage of development as fully visually equipped children.

It is a reflex to aid parent child bonding and show trust and relaxation. Male peacocks express their sexuality and draw attention to themselves with their large colorful tail unique to the males of the species. A parallel here are human breasts; the fat tissue in the breast isn’t required in order to produce milk for young suggesting it is simply to attract male attention. According to some ethologists the breast evolved as we began to walk erect and loose our reliance upon smell, a sense that provides primary information about sexual readiness in many mammals.

The breasts are therefore an alternative method of displaying one’s sex and communicating a desire to copulate. This suggests that humans may have evolved physically to be able to express them selves vocally. For example chimpanzee’s can communicate a certain amount of material through American Sign Language but would be unable to vocalize this due to the inability to use the tongue or the lips to produce sound. The relative poverty of this communication system is not a barrier to communication.

There is no struggle to express thoughts or desire, it is simply that all animals other than humans are widely considered to be confined to communication regarding stimulus, context and response. The amount of communication within a species varies inevitably depending on the day to day stimulus faced as well as years of natural evolution and intelligence levels. One can assume that the apes would be one of the most communicative of species as they are intelligent and easily comparable to humans in terms of evolution.

Apes are the closest species of animal biologically to man and of the apes the chimpanzee is the most congruous although their evolutionary paths diverged some fourteen million years ago. In fact, the chimp is more closely related to man than monkey. A combination of the genetic similarities and the chimpanzee’s ability to form attachments to human foster parents has meant it has been possible to compare clearly the progress of a human baby with a chimpanzee baby of the same age in terms of learning to speak coherently; for years people have been grappling with the question, ‘can primates acquire language’.

Although entirely consistent of stimulus and response; Primate call systems demonstrate that primates do have the ability to vocalize different dangers apparent to them. For example, Vervet monkeys will ‘chutter’ if they see a puff adder of cobra, ‘rraup’ if an eagle is visible; ‘chirp’ if a lion or leopard is present and ‘uh! ‘ at the sight of a spotted hyena or Masai person. This could constitute as a language, or at least verbal communication. However, early experimentation was unsuccessful and lent credence to the argument that language was unique to man.

Apes, like other animals were considered to be prisoners of stimulus, context and response. In the early 1950’s Vicki the chimpanzee began training to try and acquire the English language. She possessed greater ability than demonstrated and psychological constraints prevented them from being tapped. It was initially concluded that the ability to learn language might be related to arithmetic and sequence learning beyond those possessed by a chimp. The afore mentioned vervet monkeys have already proved that apes can verbally articulate at least some sounds. Among themselves, chimps communicate both by vocalization and gesture.

Vocal calls tend to be related to alarm, aggression and sources of excitation; therefore Vicky is unlikely to respond vocally as often as she may gesturally considering the situation. A gestural language could side step the chimp’s obvious difficulties with controlling vocal productions. Neither the orangutan nor the chimpanzee seems to use lips or tongue in natural calls. An orangutan was once taught to say ‘papa’ and ‘cup’ as neither lips nor tongue are needed to form the words. However it would be very difficult to find a vocabulary, which did not require these functions to cover even the most basic of communication systems.

It became painfully obvious that Vicki was never going to reach anywhere near the literacy of a small child even. However, it became increasingly clear that Vicki was keen to communicate with her hands and was very literate with them. It was decided that the deficiency was motor not mental and that it could be possible to teach language by exploiting Vicki’s facility with her hands. Little was known about the extent of the chimp’s gestural vocabulary or the complexity of the communicative system in which it is used but the suspision was growing that the chimpanzee might employ a primitive gesture language in the wild.

In 1996 a family called the Gardeners reared a female chimp named Washoe. All attempts prior to Washoe had assumed that language was synonymous with speech; with no such confusion in mind; a new method of teaching was tried. Reared in an enriched environment where all human conversations were carried out in American Sign Language, Washoe was given the closest environment possible to that of a one year old human child. Everything around her was designed to deduce whatever cognitive abilities she had and to encourage her to use sign language to express these desires.

They theorized that ‘washoe would demonstrate certain abilities humans associate with language, but that eventually the chimp would prove incapable of understanding a question or the negative or word order’ (Linden 1974) Even with the full use of hands, it is debatable whether it could be called a language without clear proof that a sentences could be constructed; ‘the essence of human language lies in the ability to create sentences’.

Since, languages have been taught to chimpanzees in the form of gestures or artificial plastic symbols. Although it is almost impossible to prove that any degree of fluency or grasp of word order has been achieved, there has definitely been unexpected success in terms of attempts to teach elements of language to chimpanzees. A change in teqnique from human language to a gestural method of communication has allowed us to tap into the minds of chimps where it has not previously been possible.

Washoe was forced to spend a couple of weeks in a zoo; for the first few days she was furious and swore constantly at the man who cleaned her cage twice a day. The gesture of rubbing the top of the hand on the underside of the chin means dirty, ie swearing. Washoe was upset at being down graded from the position of human to animal. There have recently been attempts to foster the use of human language in a colony of chimps. Projects such as these are becoming easier as we have reassessed teaching and communicative methods.

At the moment, primates cannot be considered to acquire language fluently but at least with some degree of comprehension and application. In the future we may be forced to reassess the assumption that language is unique to humans and that constraints previously assumed to be mental may actually be motor and therefore avoidable ‘in our social relations, the race is not to the swift but to the verbal-the spellbinding orator, the silver tongued seducer, the persuasive child who wins the battle of wills against a brawnier parent’ (Pinker, 1994).