Backwards in a Perfect Tree

Let us pretend for a moment that borrowing between distinct languages does not take place and that the lexical stock of any language consists partly of words inherited whole and partly of new words produced by the recombination of inherited morphological elements. Thus, the genealogies of all morphemes form neat family trees that are more or less congruent with the family trees of languages. Every language has a lineage extending indefinitely far back in time. Splits are permanent: if two languages stemming from a common ancestor diverge, their shared lineage forks out into two branches which never merge again.

Under such assumptions, it is possible to apply “coalescent thinking” to languages. If today the total number of languages is about 7,000 (give or take a few hundred), and if we know, both on the basis of our historical observations and thanks to inference from language comparison, that languages often split and diverge (but they do not converge), and that it has always been so, as far as we can tell, today’s linguistic diversity can be reduced to a much smaller number of ancestral languages spoken, say, 2,000 years ago. For example, the whole Romance group (Portuguese, Spanish, Catalan, French, Italian, Romanian, etc.) collapses into the Latin language.

Does it mean that the languages of the world were less diverse 2,000 years ago than they are now? Not necessarily. Many of the languages that were spoken at the time and contributed to the contemporaneous global diversity have died out leaving no descendants. The expansion of Latin, for example, led to the mass extinction of minority languages in many regions incorporated into the Roman Empire. One can draw a long list of languages spoken in ancient Italy itself – Etruscan, Raetic, Sicel, Oscan, Umbrian, Faliscan, South Picene, Venetic, Messapic, Lepontic, Cisalpine Gaulish, Ligurian, etc. – that had succumbed to the prestige of Latin even before the Romans completed their conquest of Gaul or the Balkans. However, if we restrict our attention to the genealogies of the extant languages, the number of ancestral lineages drops at each forking-point in the family tree that we pass travelling back in time. By the time we reach the most recent common ancestor of all the modern Indo-European languages (which, by the way, should not be confused with Proto-Indo-European), more than 400 IE languages spoken today will have become one.

The rate of language diversification is very capricious and contiguous on extralinguistic factors – quirks of history. There are tiny families lingering on against all odds, some with a single member (like Basque or Burushaski), and there are really vast ones (like Austronesian or Niger-Congo, which make even Indo-European look puny in comparison). The retrospective coalescence of a large family dramatically decreases the number of ancestral lineages. More than 30 Polynesian languages merge into one if you travel back 2,000 years; but at a deeper date you reach the coalescent point of some 1,200 Malayo-Polynesian languages (including the already collapsed Polynesian subgroup), not to mention a still deeper Proto-Austronesian horizon. A few such mergers – and thousands of modern languages are reduced to a much smaller number of common ancestors.

Blue — extant languages

Thicker lines — their lineages

Red — Proto-World 

Surely, if we only had more information about the languages of the world, or more sophisticated reconstructive techniques, we would be able to increase the sensitivity and the time-depth of the comparative method, and go on reducing things. The 7,000 speech communities of today would merge into, say, 50 common ancestors several millennia ago, and perhaps eventually into one, in the same way as the genealogies of the Y chromosomes of currently living men coalesce on a single individual whom we call Y-Chromosomal Adam. Let’s call that hypothetical language “Proto-World” (see the diagram above). Of course there would have been many – possibly hundreds – other languages contemporary with it. It would only be special with hindsight: the descendants of those other languagues have not survived till now, not necessarily because they were in any way inferior, but simply because they were less lucky.

Is there any chance that Proto-World as defined above actually existed and that it could be reconstructed? I don’t think so, but I’ll explain my scepticism in the next post.

[► Back to the beginning of the Proto-World thread]