By Jesse Shanahan
Despite Earth being replete with biological and cognitive diversity, human language remains an entirely singular communicative system; no other living creature has an analogous method of self-expression. The unparalleled power of language to represent thought is the foundation for interpersonal relationships, culture, and is an inextricable component of all societies. The emergence of language is one of the most remarkable evolutionary events in the history of our planet and yet, although it is a universal part of human life and even intrinsic to human identity, its origin and exact nature remain a mystery.
The problem is that language is necessarily complex and weaves together human cognition, neurology, biology, behaviour, and psychology in a way that inhibits comprehensive or collaborative studies. For every aspect of human life that language enables, another theory of its origin and evolution exists as well. In a sense, the way language is studied depends entirely on the perspective of the person analysing it. A biologist, for example, will characterise language differently than a psychologist and will use different terminology to do so. Although seemingly contradictory, each of these views holds a piece of the puzzling origin of language: a question that remains one of the deepest unanswered mysteries concerning what it truly means to be human.
Much like astronomers, evolutionary linguists cannot directly interact with their object of study and must extrapolate backwards using data gathered from present day languages. This is possible because languages follow evolutionary patterns in terms of how sounds develop or words change. However, if the goal is to study the origin of language as a whole, then what was the first language? Even more so, how can we identify the first language if we cannot first define what a language even is? Surprisingly, constructing an exhaustive definition has proven to be an immensely difficult task that is further complicated by language’s numerous features, each of which interacts differently with human cognition, has different genetic roots, and likely has a different evolutionary path. Given just how interdisciplinary language is, settling on an accepted definition is further impeded by the contradicting terminology, distinct methodology, and differing norms in those various scientific disciplines.
Broadly speaking, linguists divide language into the following six categories: phonetics, morphology, phonology, syntax, semantics, and pragmatics. Phonetics and phonology are concerned with the speech sounds or signs of a language and how discrete units of sound (phonemes) are organised into meaningful words. Morphology studies the formation of words from meaningful units (morphemes), and syntax refers to how sentences are constructed from those words. More abstractly, semantics analyses the nature of meaning while pragmatics observes the relationship between context and meaning.
These divisions are solely linguistic, however. Other branches of science divide the study of language differently. For example, a more biological approach might distinguish between the genetic foundation of language, the anatomy of the human vocal tract, and the neurological features of the brain that allow for the production of speech and interpretation of meaning. Still, the linguistic model enables us to subdivide language into parts like sentences, words, morphemes, and phonemes, and then compare how those parts appear in different languages. Ideally, the characteristics that are common to all languages would then form a definition of language. A version of this approach was popularised by Noam Chomsky, an American linguist and philosopher, who argued that there are universal elements to all languages and that human beings will always develop languages with those elements.
In Chomsky’s theory, ‘Universal Grammar,’ these ubiquitous traits of language are hardwired into human beings via genetics, explaining why language is a uniquely human attribute. Although this is an attractive idea, the theory remains an ongoing source of disagreement among linguists. The sheer degree of linguistic diversity appears to undermine Chomsky’s claim that all human brains have the same set of structural rules for language, and languages have been discovered that seemingly lack those structure rules. More broadly, some scientists have argued that, because Universal Grammar is defined based the observed features of human language, it cannot be proven wrong. Instead, they argue that a truly scientific theory should make predictions, which can then be supported or refuted with evidence. Furthermore, some evolutionary biologists have also objected to Chomsky’s theory because, despite the claims of a genetic origin to human language, it conflicts with modern principles of Darwinian evolution. For example, how could language require a universal biological foundation when it evolves at significantly faster speeds? Simply put, how could a genetically coded grammar ever keep pace with a constantly evolving language?
Even if Chomsky’s theory has been heavily criticised and largely discredited, it is the perfect example of a common linguistic strategy in defining language. By comparing diverse human languages, it is not only possible to identify the so-called ‘linguistic universals’ that define language but also to deduce probable features of the very first proto-language. Another similar approach to defining language is to compare human languages with the numerous methods of communication in the animal world. Complexity is hardly an attribute reserved solely for human language, and many species have robust, detailed systems for transmitting meaning. However, linguists reserve the term ‘language’ only for systems that give users both an unlimited array of meaningful, arbitrary expressions and the ability to innovate brand new ones. As far as we know, no animal method of communication has these features. An easy example of this distinction can be illustrated with what has been ironically named ‘body language’. Whether a person crosses their arms or gesticulates wildly is certainly meaningful, but it hardly constitutes a language. Similar analogies can be used with facial expressions, training commands taught to dogs, and musical humming. In contrast, gestural or signed languages provide the user with an infinite variety of phrases and the ability to craft new terms as the language evolves. Whereas both body language and gestural languages have meaning of one type or other, only the signed languages have the complexity, scope, and creativity required of a full language.
American linguistic anthropologist Charles Hockett described this distinction in terms of a set of attributes that he called ‘design features’. Like Chomsky, he attempted to define a list of the universal characteristics of all human languages. Notable design features include semanticity, which is the fact that certain combinations of sounds are connected to specific meanings, and arbitrariness, or the lack of connection between a word and its meaning. Hockett’s design features also list discreteness, or the ability of language to be broken into distinct parts, and displacement: the ability of human speakers to reference things that do not exist, e.g. the past or the future. Similarly, Hockett also required that language is productive; it enables speakers to create an unlimited number of new expressions. Although not every linguist agrees with Hockett’s requirements, his set of design features provides an excellent framework to understand the distinction between communication and language.
For example, ornithologists have discovered that bird communication utilises both semanticity and arbitrariness. Bird calls and songs also have discreteness, as they can be divided into individual units of meaning which can then be arranged using a kind of syntax. Dialect variations, mimicry, and even limited acquisition of human language has been observed, though debate still remains over whether the birds truly learned some human language or are simply emulating human behaviour. Still, the communication systems of birds fail Hockett’s productivity requirement, as they have a limited list of musical expressions and cannot innovate new ones. Birds also cannot reference nonexistent things (displacement), and they cannot utilize their calls to reference abstract concepts. Similarly, there are numerous other animal systems of communication, like those of bees or chimpanzees, that seem to parallel human language but invariably lack some critical trait when analysed using Hockett’s design features. Even if other linguists dispute some of Hockett’s framework, it aptly illustrates the complexity, breadth, and uniqueness of human language in addition to the difficulty of defining it.
While comparative analyses or guidelines like Hockett’s design features bring us closer to an understanding of what language is, numerous ontological questions remain. We cannot even say whether language initially developed in songs, gestures, or speech, or when exactly proto-humans began to utilise complex systems of communication. A groundbreaking study published in 2017 discovered that the first anatomical evidence for increased vocal capability occurred roughly 4.5 million years ago. By comparing the skulls of various chimpanzees and those of A. ramidus, an extinct bipedal hominin from the early Pliocene epoch, researchers identified the emergence of anatomical features associated with vocal ability. Not only does this potentially suggest that language could have developed significantly earlier than previously thought, but this change in anatomy has also been correlated with decreased aggression in the species, which would further enable social interaction and the development of communication.
Similarly, a study at Yale University in June 2018 revealed a relationship between the number of phonemes in a given language and the expression of a gene associated with dyslexia. Another study conducted in 2012 discovered that humans developed a specific biological adaptation that enables us to keep up with the quick pace of language evolution, and for humans that evolved in one geographical region to quickly and adeptly learn languages that developed in another. Additionally, social groups, familial relationships, the increased use of tools, and the desire for self-expression have also all been suggested as potential origins of language.
Interestingly, Hockett’s design features apply to this problem as well. By looking at the uses language has, we can identify even more possible motivations for its emergence. For example, the productivity of language suggests human beings developed a creative impulse in addition to a desire for self-expression. Likewise, the abstraction feature of language has a connection with our ‘theory of mind’: the ability to conceptualise our own thoughts, beliefs, intents, desires, etc., and ascribe similar ones to other people. Whether language caused those characteristics to develop in human beings or whether our own needs drove its design is still a matter of contentious debate. Thus, we often cannot even distinguish between a cause of language development or an effect of its evolution in our species.
Still, these setbacks are understandable. Modern language is incredibly multifaceted; in the same way that language is entwined with our anatomy, cognition, psychology, and society, the first languages likely emerged due to a complex combination of influences as well. The strength of the relationship between language and the human experience makes disentangling its effects, causes, evolution, and origin even more difficult. When, if ever, we are finally able to understand the birth and evolution of language, we will have found an answer to one of the hardest unsolved problems in science.
And yet, this explanation has an unsettling implication. Given that no other species on Earth has developed a system with the complexity, scope, and capability of human communication, achieving all of the requirements for language might be an incredibly rare event. Just as the uniqueness of biological life on Earth drives us to wonder if we are isolated in the universe, the singular existence of language in human beings raises the question: even if we aren’t alone, will we ever find another species who can truly understand us?