By Dr Laila Abdel Aal Alghalban
Why can’t apes, our closest fellow mammals, speak though they share about 99 per cent of our DNA? Why is human language unique? And what does it mean to be human? Language is what makes us different; what sets us apart from non humans. Without language, humans cannot build knowledge, social relations, cultures and therefore civilisations. Language is a key part of who we are. Scientifically speaking, what we mean by language is the language faculty we are born with; what is in our brains, in our ways of thinking and in our linguistic practices. Language is not invented; it is something that happens to us, as many philosophers of languages say. The legendary linguist Noam Chomsky argues that language is a biological endowment; it is a part of our biological makeup; it is language with capital L. What’s special about human language?
Exceptional properties of language
At the end of the 50s and the beginning of the 60s, the linguist Charles Hockett elaborated his theory about the exceptional design of human language.
He singled out some properties. One is ‘open-endedness’; it refers to the creativity or the productivity of human language. We do not invent a lot of vocabulary during our lifetime nor do we change grammar profoundly, but we can produce an endless number of sentences, many of which are new.
Language is a computational system, the backbone of which is mental grammar that allows humans to make sounds and utterances in a way that others can understand. Our intuitive grammatical knowledge is necessary for parsing sentences, i.e. identifying the grammatical function of words in sentences and the permissible combinations of words to generate well-formed structures.
In contrast, animals communicate within closed systems, with limited signals and, hence, limited possible messages to convey.
Animals make sounds to mate, indicate danger, assume power, among others, utilising closed systems of signals. No animal has ever tried to improvise other signals or combine two signals to create new meanings.
The second property of human language is ’displacement’, the ability of language to talk about things beyond the here and now. Unlike animals, we are not locked or imprisoned in the situational context or the seen horizon; we tear the fabric of place and time.
Another related property is ‘stimulus freedom’; human communication is not bound to the stimulus. We can make responses free from the situational stimulus; we can talk about unreal or imaginative things. Monkeys, for instance, never make fake warning calls because it didn’t cross their minds there to do such things.
Humans lie, thanks to displacement and stimulus freedom.
Let’s move on to two other interrelated characteristics, namely ‘discreteness’ and ‘duality’. The former refers to the unique and contrastive sounds of human languages.
These discrete, chopped sounds are themselves meaningless; we do not know what is the meaning of the sound ‘k’, ‘a’, or ‘t’. But when combined, these sounds create words such as ‘cat’, ‘act,’ and ‘tack.’ Duality refers to these two levels: the level of discrete sounds and the level of meanings.
We create words to refer to things and concepts and, as a society, we agree on this naming or labelling processes.
The relationship between a word and its referent becomes conventional, purely arbitrary. What’s the relationship between the word ‘dog’ and the animal dog? No logical, intrinsic or natural relationship; it is just an arbitrary one.
The fact that discrete sounds are meaningless is super important to human language creativity. Had each sound had only one meaning, humanity would have communicated with only 100 meanings or 100 messages and would have been locked in such a very closed signalling system like non humans. Fortunately, human language is gifted with this incredible property called ‘discreteness.’
How many different unique, distinctive sounds can human vocal tract create? Actually, it’s about 100. All human languages utilise about 100 discrete, contrastive sounds (technically termed ‘phonemes’) in total. This number varies from one language to another. In English, for example, there are about 40 or 44 phonemes. In many languages, the number could be fewer or larger than that.
Language is not inherited
It is subject to change in place and time, a fact we shouldn’t be worried about nor resist. History keeps telling us this fact and we might be surprised, even shocked, to know that so many words we currently use were unacceptable in the past. Each generation feels that changing language is their undisputed right and defines it by the values and view points of the world they share.
The human vocal tract
It has been argued that the very anatomical structure of the human vocal tract substantially makes human language really unique.
Comparing the human vocal tract to the vocal tract of an ape, you would be stunned by huge aspects of similarity. However, the muscles of human lips and the tongue are very elastic; the teeth are upright, not slanting; the mouth is small to open and close so easily.
More importantly, the hyoid bone, which is unique to human body and not linked to any other bone, supports the tongue and creates a wider pharynx between the larynx and the tongue, used as a resonating chamber to amplify sound and create speech in a convenient way.
Another anatomical difference is the structure of the epiglottis which shuts the windpipe. It is significantly longer in apes than in humans, which also gives room for a wider pharynx to create amplified speech.
It’s true that the anatomical structure of speech organs in humans and apes is different to some extent, yet recent research in neuroscience illustrates that human language faculty cannot be solely attributed to anatomical differences.
Rather, it is credited to the special neurological structure of the human brain. Unlike apes and other mammals, humans have neural control on the processes their brains make, which cause language production and processing.
Images of the human brain circuits show the language areas we have, including Broca’s region, which is responsible for speech production in the frontal lobe, and the Vernick area, which is responsible for the processing of speech.
The neuro-connections and circuits between language areas involve billions of neurons, neural pathways and electro-chemical interactions. A mental lexicon is compiled and arranged in accordance with a semantic network. Thought begins when words from different areas in the brain wire together and after repetition of simultaneous wiring they fire together.
A message is formulated and then motor cortex gives orders to the larynx and other speech organ to act and turn the message into sound waves to hit the listeners’ eardrums and turn into electromagnetic signals sent eventually to the brain to filter and process.
Apes, on the other hand, do not develop similar circuits or computational systems. Therefore, it becomes impossible for them to speak although they have similar speech organs.
Finally, the mysteries of human language would continue to puzzle, stun and wow us as well as all future generations, granting us all beautiful aha moments.
By Dr Laila Abdel Aal Alghalban
Professor of Linguistics, Faculty of Arts
Kafr el-sheikh University
Email: [email protected]
