In the same way that attempts have been made to show that tool making is not a fundamental feature of humanity, so some have tried to show the same thing in relation to language. The part of the brain known as Broca’s area is associated with language, and was thought to be unique to humans. It is now known that this area also exists in other animals. This fact has been used to dispute the idea that the acquisition of language is unique to humans. But this argument seems extremely feeble. The fact remains that no species other than humans depend upon language for their existence as a species. Language is essential to the social mode of production, which is the basis of human society.

In order to prove that other animals can communicate to some extent, it is not necessary to study the behaviour of bonobos. Many of the lower species have quite sophisticated systems of communication – not just mammals, but also birds and insects. Ants and bees are social animals and have highly developed forms of communication. These, however, cannot be taken as implying intelligent thought, or thought at all. They are inborn and instinctive. They also are quite limited in scope. The same actions are repeated endlessly and mechanically and are no less effective for that. But few would regard this as language as we understand it.

A parrot can be taught to repeat whole sentences. Does this mean it can talk? It is fairly clear that, while it can imitate sounds quite well, it has no understanding of what the sounds actually mean. But the conveyance of meaning is the essence of intelligible language. Things are different with the higher mammals. Engels, who was a keen hunter, was not sure to what extent dogs and horses did not partially understand human speech and feel frustrated at not being able to talk. Certainly, the level of understanding shown by the bonobo Kanzi in captivity is quite remarkable. In spite of all this, there are specific reasons why no animal other than humans has a language. Humans alone possess a vocal tract that permits the production of consonants. No other animal can pronounce consonants. Some can make clicking and hissing sounds. In fact, consonants can only be pronounced together with vowels, or they would be reduced to clicks and hisses. The ability to pronounce consonants is a product of walking on two feet, as the study on Kanzi shows:

“Man alone has a vocal tract that permits the production of consonants sounds. These differences between our vocal tract and that of apes, while relatively minor, are significant and may be linked to the refinement of bipedal posture and the associated need to carry the head in a balanced, erect position over the centre of the spine. A head with a large heavy jaw would cause its bearer to walk with a forward list and would inhibit rapid running. To achieve balanced upright posture, it was essential that the jaw structure recede and thus that the sloped vocal tract characteristic of apes become bent at a right angle. Along with the reduction of the jaw and the flattening of the face, the tongue, instead of residing entirely in the mouth, was lowered partially down into the throat to form the back of the oropharynx. The mobility of the tongue permits modulation of the oropharyngeal cavity in a manner that is not possible in the ape, whose tongue resides entirely in the mouth. Similarly, the sharp bend in the supralaryngeal airway means that the distance between the soft palate and the back of the throat is very small. By raising the soft palate, we can block off the nasal passage-ways, permitting us to form the turbulence necessary to create consonants.”

Without consonants, we cannot easily distinguish between one word and another. We would just have howls and screeches. These can convey a certain amount of information, but it is necessarily limited:

“Speech is infinitely varied and currently only the human ear can readily find the meaningful units in these infinitely varied patterns. The consonants permit us to accomplish this feat.” Human infants are able to categorise consonants in a way similar to adults from a very early age, as anyone who has listened to “baby talk” will know. It consists precisely of constantly repeated experiments with combinations of consonants and vowels –”ba-ba, pa-pa, ta-ta, ma-ma”, and so on. Even at this early stage, the human infant is performing a task which no other animal is capable of.

Should we then conclude that the only reason that other animals lack speech is physiological? That would be a serious mistake. The shape of the vocal tract, and the physical ability to combine vowels and consonants are the physical preconditions for human speech, but no more than that. Only the development of the hand, inseparably connected with labour and the need to develop a highly co-operative society, made possible the enlarged brain and language. It seems that the area of the brain related to the use of tools and language have a common origin in the early development of the nervous system of a child, and only become separated from the age of two, when Broca’s area establishes differentiated circuits with the anterior prefrontal cortex. This, in itself, is striking proof of the close link between tool making and language. Language and manipulative skills developed together, and this evolution is reproduced in the development of human infants today.

Even the earliest hominids of the Oldowan culture had manipulative skills far in advance of the apes. They were not just “upright chimpanzees”. The manufacture of even the simplest stone tool is far more complex than it seems. It requires planning and foresight. Homo habilis had to plan ahead. He had to know that at some time in the future he would need a tool, even though, he had no such need in the moment when he discovered the appropriate material. The careful selection of the right kind of stone, and the rejection of others; the searching out of the right angle to strike a blow; this showed a level of thinking ability qualitatively different to that of apes. It seems unlikely that at least the rudiments of language were not present at this stage. But there is further evidence which points in this direction. Humans are unusual in that 90 per cent are right-handed. Such a preference for one hand is not found in other primates. Individual apes may be right-handed or left-handed, but the population as a whole will break down into two equal halves. The phenomenon of handedness is closely connected with manipulative skills and language:

Handedness is associated with localisation of function to the opposite brain hemisphere. The location of manipulative skills in the left hemispheres of (most) right-handers is accompanied by the location there of language skills, too. The right hemisphere has become specialised for spatial skills.

This phenomenon is absent in Australopithecus, but has been found in the earliest known skulls of Homo habilis, the first toolmaker. It is highly unlikely that this is a coincidence. By the time we reach Homo erectus, the evidence becomes overwhelming:

These three lines of anatomical evidence – of the brain, the vocal apparatus, and the capacity for tool-use – provide the principal support for the notion of long, gradual changes on the road to language. Along with these changes in the brain and the vocal apparatus, there occurred concomitant gradual changes in the hand, changes that made it an increasingly suitable instrument for tool construction and use.[49]

The emergence of humankind represents a qualitative leap in evolution. Here, for the first time, matter becomes aware of itself. In place of unconscious evolution, we have the commencement of history. In the words of Frederick Engels:

With man we enter history. Animals also have a history, that of their descent and gradual evolution to their present position. This history, however, is made for them, and in so far as they themselves take part in it, this occurs without their knowledge and desire. On the other hand, the more that human beings become removed from animals in the narrower sense of the word, the more they make their history themselves, consciously, the less becomes the influence of unforeseen effects and uncontrolled forces on this history, and the more accurately does the historical result correspond to the aim laid down in advance.

If, however, we apply this measure to human history, to that of even the most developed peoples of the present day, we find that there still exists here a colossal disproportion between the proposed aims and the results arrived at, that unforeseen effects predominate, and that the uncontrolled forces are far more powerful than those set into motion according to plan. And this cannot be otherwise as long as the most essential historical activity of men, the one which has raised them from the animal to the human state and which forms the material foundation of all their other activities, namely the production of their requirements of life, i.e., in our day social production, is above all subject to the interplay of unintended effects from uncontrolled forces and achieves its desired end only by way of exception, but much more frequently the exact opposite…

Only conscious organisation of social production, in which production and distribution are carried on in a planned way, can lift mankind above the rest of the animal world as regard the social aspect, in the same way that production in general has done this for mankind in the specifically biological aspect. Historical evolution makes such an organisation daily more indispensable, but also with every day more possible. From it will date a new epoch of history, in which mankind itself, and with mankind all branches of its activity, and particularly natural science, will experience an advance that will put everything preceding it in the deepest shade.[50]

  1. Savage-Rumbaugh, S. and Lewin, R. op. cit., pp. 226-7, 228 and 237-8.

  2. Engels, F. Dialectics of Nature, pp. 48-9.