Origin of Language - Approaches

Approaches

Approaches to the origin of language can be divided according to their underlying assumptions. 'Continuity theories' are based on the idea that language is so complex that one cannot imagine it simply appearing from nothing in its final form: it must have evolved from earlier pre-linguistic systems among our primate ancestors. 'Discontinuity theories' are based on the opposite idea — that language is a unique trait so it cannot be compared to anything found among non-humans and must therefore have appeared fairly suddenly during the course of human evolution. Another contrast is between theories that see language mostly as an innate faculty that is largely genetically encoded, and those that see it as a system that is mainly cultural — that is, learned through social interaction.

Noam Chomsky is a prominent proponent of discontinuity theory, an issue on which he stands quite isolated among his academic peers. He argues that a single chance mutation occurred in one individual on the order of 100,000 years ago, triggering the 'instantaneous' emergence of the language faculty (a component of the mind-brain) in 'perfect' or 'near-perfect' form. The philosophical argument runs, briefly, as follows: firstly, from what is known about evolution, any biological change in a species arises by a random genetic change in a single individual which spreads throughout its breeding group. Secondly, from a computational perspective on the theory of language: the only change that was needed was the cognitive ability to construct and process recursive data structures in the mind (the property of "discrete infinity", which appears to be unique to the human mind). This genetic change, which endowed the human mind with the property of discrete infinity, Chomsky argues, essentially amounts to a jump from being able to count up to N, where N is a fixed number, to being able to count indefinitely (i.e. if N can be constructed then so can N+1). It follows from these assertions that the evolution of the human language faculty is saltational since, as a matter of logical fact, there is no way to gradually transition from a mind capable only of counting up to a fixed number, to a mind capable of counting indefinitely. The picture then, by loose analogy, is that the formation of the language faculty in humans is akin to the formation of a crystal; discrete infinity was the seed crystal in a super-saturated primate brain, on the verge of blossoming into the human mind, by physical law, once a single small, but crucial, key stone was added by evolution.

Continuity based theories are currently held by a majority of scholars, but they vary in how they envision this development. Among those who see language as being mostly innate, some — notably Steven Pinker — avoid speculating about specific precursors in nonhuman primates, stressing simply that the language faculty must have evolved in the usual gradualistic way. Others in this intellectual camp — notably Ib Ulbæk — hold that language evolved not from primate communication but from primate cognition, which is significantly more complex. Those who see language as a socially learned tool of communication, such as Michael Tomasello, see it developing from the cognitively controlled aspects of primate communication, these being mostly gestural as opposed to vocal. Where vocal precursors are concerned, many continuity theorists envisage language evolving from early human capacities for song.

Transcending the continuity-versus-discontinuity divide are those who view the emergence of language as the consequence of some kind of social transformation that, by generating unprecedented levels of public trust, liberated a genetic potential for linguistic creativity that had previously lain dormant. 'Ritual/speech coevolution theory' is an example of this approach. Scholars in this intellectual camp point to the fact that even chimpanzees and bonobos have latent symbolic capacities that, in the wild, they rarely if ever use.

Because the emergence of language is located so far back in human prehistory, the relevant developments have left no direct historical traces; nor can comparable processes be observed today. Despite this, the emergence of new sign languages in modern times — Nicaraguan Sign Language, for example — might potentially offer insights into the developmental stages and creative processes necessarily involved. Another approach has been to inspect early human fossils, looking for traces of physical adaptation to language use. In some cases, when the DNA of extinct humans can be recovered, the presence or absence of supposedly language-relevant genes — FOXP2 is an example — might prove informative. Another approach, this time archeological, is to invoke symbolic behaviour (such as repeated ritual activity) that may leave an archaeological trace—such as mining and modification of ochre pigments for body-painting—while developing theoretical arguments to justify inferences from symbolism in general to language in particular.

The time range for the evolution of language and/or its anatomical prerequisites extends, at least in principle, from the phylogenetic divergence of Homo (2.3 to 2.4 million years ago) from Pan (5 to 6 million years ago) to the emergence of full behavioral modernity some 150,000 - 50,000 years ago. Few dispute that Australopithecus probably lacked vocal communication significantly more sophisticated than that of great apes in general, but scholarly opinions vary as to the developments since the appearance of Homo some 2.5 million years ago. Some scholars assume the development of primitive language-like systems (proto-language) as early as Homo habilis, while others place the development of symbolic communication only with Homo erectus (1.8 million years ago) or Homo heidelbergensis (0.6 million years ago) and the development of language proper with Homo sapiens less than 200,000 years ago.

Using statistical methods to estimate the time required to achieve the current spread and diversity in modern languages today, Johanna Nichols — a linguist at the University of California, Berkeley — argued in 1998 that vocal languages must have begun diversifying in our species at least 100,000 years ago. Using phonemic diversity, a more recent analysis offers directly linguistic support for a similar date. Estimates of this kind are independently supported by genetic, archaeological, palaeontological and much other evidence suggesting that language probably emerged somewhere in sub-Saharan Africa during the Middle Stone Age, roughly contemporaneous with the speciation of Homo sapiens.

Linguists agree that, apart from such things as pidgins, there are no "primitive" languages: all modern human populations speak languages of comparable expressive power, though much recent scholarship has explored how linguistic complexity varies between and within languages over historical time.