Both the Bible and the Koran trace the origin of language back to the origin of humanity, seeing language as words, but without specifying which language the words were part of, or how this insight related to the ways that words are put together, or how long ago this was. But the notion of simultaneous origins of language and humanity is either a very ancient one, or, for believers, a divine truth.

By the proposal here, the question of how human language originated is in fact crucial to speech and language pathology.

Out of Africa

The issue here was sharpened by Charles Darwin’s Origin of Species in 1859: Did human language originate in Africa? Such questions led to a flurry of speculation, leading to a ban seven years later by the Société de Linguistique de Paris on any discussion of language evolution. If, as Darwin guessed, humans originated in Africa, did language originate in Africa too? As Salikoko Mufwene (2013) notes, the anxiety of the Société de Linguistique may have stemmed from the realisation that if language originated in Africa, it was bequeathed to humanity by Africans. Some members of the Société de Linguistique may have been less than happy about any such thought. The ban silenced scientific debate until Lenneberg (1967) brought the topic back to life with a final chapter by Noam Chomsky.

Now a combination of genetic and paleoanthropological evidence suggests strongly that Darwin was right: Language, like the human species itself, originated in Africa. Call this the ‘Out of Africa Hypothesis’. David Reich (2018) complicates the picture with his demonstration that there was some migration back into Africa after the exodus of modern humans around 70,000 years ago. But from various sorts of evidence, including stone tools in dateable deposits, by the work of Curtis Marean and his colleagues (2007), a population living on what was then a South African shoreline between 130,000 and 175,000 years ago was able to anneal flint, heating it red hot and letting it cool slowly over a period of a day or so. Such a technology requires an understanding of heat and accurate control of fire. This would be especially challenging without instruments or industrial / laboratory apparatus. It seems to me, as it does to Marean, that such a population must have had a fully developed competence in language. If that thinking is on the right lines, the last step of human language evolution must have been completed by that point. There is no way of telling what the speech sounded like, although it may have had a large inventory of speech sounds, some with complex articulations like some of the so-called  ‘click languages’ still spoken in Southern Africa.

Proto-Indo-European or Proto-Indo-Uralic

Apart from Basque, 300 odd languages (some now dead) from Western Europe and from Kurdistan and Iran to Northern India are thought to have originated somewhere close to the Black Sea perhaps 6,500 years ago. This language is known as ‘Proto-Indo-European’ or PIE. Going back another 2,500 years, there may have been an ancestral form of PIE including modern Hungarian and Finnish, known as ‘Proto-Indo-Uralic’ PIU. There is no reason for not assuming that PIE and PIU were already fully developed modern languages, before they started developing in separate directions into the languages of Europe, Northern India, and the ancient Middle East. This development is often known as ‘grammaticalisation’, and evident in the way Old English willan, meaning to want, has become modern will, denoting a future event, commonly reduced to L, and stuck onto the right edge of the preceding word, as in “I’ll do that”.

PIE, about which the evidence is much clearer and better established than that for PIU, was ancestral to Sanskrit, Classical Greek, Latin, and gradually diverged more widely. The idea of this ancestry we owe to William Jones in 1786. Although others had seen the connections, it was Jones who both identified criteria still broadly accepted today for genetic relationships between languages. What we still have from PIE are the terms for numbers, members of the family, personal pronouns like thee and me, words for snow, bodies of water, and other terms relating to love, life and death.

This process is often described and illustrated graphically by the branching of a tree, with ‘Romance’ languages including Spanish, Portuguese, French, Italian, and Romanian, Celtic languages once spoken in Britany, Cornwall, Wales, Scotland and Ireland, Nordic languages, spoken in Denmark, Norway, Sweden, the Faroes, Iceland, Slavic languages including Russian, Polish, Bulgarian, Serbian, Czech, and so on, all on their own branches. But there is one glaring counter-example, English. Modern English represents not just branching but a growing back together, which has happened in very complex ways from the end of the Roman occupation in 410 and at least to the Norman conquest in 1066, and possibly for another 500 or so years, as the class demographics reacted to phenomena such as the Black Death which killed almost half the population.

Two pulls

On the grammaticalisation time scale. there are pulls in two opposite directions, to simplify for the sake of least effort, and to increase distinctiveness for the sake of clarity. The most that can be done by way of reconstruction is to plot some of the possible forms.

For children, being able to talk is an obvious goal. But the goal changes, as is obvious from differences between English today, and the English of Dickens, Shakespeare, and Chaucer, getting more and more different, as the centuries roll by. Not even the speech of Shakespeare a mere 400 years ago would be easily understandable to a modern listener. Even within a human lifetime it is possible to detect the beginnings of change. Great grand parents often have difficulty understanding their youngest descendants.

Time scales

There are thus two time scales, an evolutionary one for language, and a grammaticalisation one for languages, as well as other time scales which are revealed by experiment and analysis.

Summary

Language changes inexorably.