The mystery of language origins: How did we come to develop a communication system is so much richer than that of other animals? This hotly debated topic is related to the „language gene“ controversy and is also popular in the media. Every few months, we get another story about how some new finding has solved the mystery of language origins.
Language was spoken long before it was ever written down, so there is no record of what language might have been like tens of thousands of years ago. We do know that all contemporary languages have essentially the same level of complexity and expressiveness - there are no fossil languages to give us clues on their origins. We also now have a rich and detailed literature on how languages can change rather rapidly. We can't work back that from current languages and preserved texts to some common precursor; language changes much to fast and varied.
Some relevant information can be gathered from paleontology, particularly from the shape of discovered skulls, drawers, and related skeletal remains. Producing the full range of human language sounds apparently requires some anatomical adaptions that are not present in the early hominids and certainly not in contemporary apes. But, at best, this kind of finding can provide us only with some crude estimates of when human languages might have started evolving, not how.
Noam Chomsky‘s position is the touchstone for most of the discussions within linguistics. His current stance is that there is a core linguistic competence that is unique to humans and disjoint from other neural systems; this is completely consistent with the modularist stance. Chomsky makes the reasonable argument that no animal rule systems approach the complexity of human grammar. The conclusion is that human language (core grammar) is the result of a single large mutation. Other modularists, notably Steven Pinker, argue that continuous evolution produced the innate, autonomous, formal grammar module.
But neither side in this latest argument says much about how language came to be the organising force of human culture. Of course, if you believe that languages just one manifestation of a bigger brain with superior learning ability, there's nothing much to explain. Language got started somehow, and, because it's so adaptive, people learned to be better and better at it. People also developed many other intellectual skills, some related to language and some not.
Among the many other theories of the origins of language, Derek Bickerton produced the most complete and widely regarded. He started by looking at Creoles, languages that develop ad hoc when people without a common language are forced to communicate. He suggested that all Creoles start from the same simple grammatical structure, which might well be the prototype for the original human grammar. There are also claims that the same primitive grammar structure is universally found in small children and in great apes that are taught human language. The proposed proto-grammar lacks grammatical function words and endings and relies only on word order to structure meaning. This is an attractive hypotheses and could even be right, but the evidence for it is lacking. English-speaking children do start like this, but children from cultures with morphologically complex languages such as Turkish and Eskimo use grammatical markings very early. There is also good evidence that bilingual children learn quite early to obey the different word orders used in their two languages. The results from Michael Tomasello and his colleagues suggest that children's early grammar rules are not generalised at all, but are focused on individual constructions.
The evidence from the development of Creoles is also more complex than originally thought. It is true that the first generation to be native speakers of a Creole are much more fluent than their parents, and this is additional strong evidence for the special nature of first-language learning. But it does not seem to be the case that these children develop a totally new grammar. The elements of the Creole grammar can be seen in the base grammars of the languages from which it arises.
327 There is good evidence that people tend to produce systematic grammars, but people also favour systematic explanations of other experience. The results on Creole languages do not provide insight into the possible special character of grammar or on how it may have evolved.
So, the mystery of the origins of human language is not likely to be solved any time soon. But it is not a profound mystery. Everyone agrees that expressive language conveys very significant evolutionary advantages on groups that can use it. Biological evolution moves too slowly to explain the rise of language (and modern civilisation) in just some thousands of years, but cultural evolution is easily fast enough. In a general way, it must be true that the genesis of language was neither a biological events nor individual learning, but the social phenomenon. The biological precursors, whether specific to language or more general, were almost certainly evolving well before the rapid rise of language. The mathematics of this kind of rapid change from a slowly evolving base is well understood as part of dynamical systems theory.
328 Our neural theory of language suggests that simulation might well be a cornerstone in the evolution of human language and thought. As we have seen, converging evidence indicates that people understand language and other behaviours at least in part by simulation or imagination. This ability to think about situation is not bound to the here and now (displacement) is also obviously necessary for evaluating alternatives, for planning, and for understanding other minds. We discuss this ability in terms of mental spaces.
I believe there is a plausible story about how a discreet revolutionary change could have given early hominids simulation capability that helped start the process leading to our current linguistic abilities. Mammals in general exhibit at least two kinds of involuntary simulation behaviour - dreams and play. While a cat is dreaming, a centre in the brain stem blocks the motor nerves so that the cat’s dream thoughts are not translated into action. If this brainstem centre is destroyed, the sleeping cat may walk around the room, lick itself, catch in imaginary mice, and otherwise appear to be acting out its dreams. There is a general belief that dreaming is important for memory consolidation in people, and this was also be valuable for other mammals. Similarly, it is obvious that play behaviours in cats and other animals have significant adaptive value.
Given that mammals do exhibit involuntary displacement in dreams, it seems that only one revolutionary adaption is needed to achieve our ability to imagine situations of our choosing. Suppose that the mammalian involuntary simulation mechanisms were augmented by brain circuits that could explicitly control what was being imagined, as we routinely do. This kind of overlaying a less flexible brain system with one that is more amenable to control is the hallmark of brain evolution, and no one it would be surprised to find another instance of this mechanism. Now, hominids who could do detached simulations could relive the past, plan for the future, and be well on their way to simulating other minds. Understanding other minds would then provide a substrate for a richer communication and all the benefits that accrue from the use of mental spaces.
One crucial component of mental space reasoning is the ability to map ideas from one mental space to another. This is how we draw lessons from the past or change our plans after thinking about the consequences. People can predict what someone is likely to do based on what she says. So, our general simulation faculty must include the ability to maintain and exploit relational mappings. The learning of grammar could be very nicely modelled as learning relational mappings between regularities of linguistic form and the underlying meaning they convey, and some such mapping abilities seems to be required under any theory of grammar. Even more speculatively, the combined ability to imagine separate scenarios and to map them together is perhaps one of the foundations of many human capabilities, including grammar. This is close to the proposal of cognitive scientists Gilles Fauconnier and Mark Turner in a recent book „The Way We Think“ (2002).
Whatever combination of biological and cultural evolution gave rise to early human language, it is no mystery that it developed rapidly, and, in all cultures, has a vast array of uses in human communication and thought. We would love to know more about how language evolved, but it is unlikely that any theory of language origins would change our basic ideas of who we are and how the world works.
The Origin of Language