Language family trees: what are they good for?

Genealogical trees have been used extensively in historical linguistics. They are a visual representation of the relationships between an original language, normally extinct, and its descendants, through a series of divisions and subdivisions that have taken place during long periods of time. A familiar example would be the genealogical tree of Romance languages, stemming from Latin. Another example is the IE familiy tree, which has been portrayed in a variety of forms. In this post you can find a couple of pictures depicting the IE 'family' (the first one is really beautiful, with its leaves and branches; the second one is a more prosaic diagram).

The idea behind family language trees seems quite reasonable. It is based on analogous types of representation found in other sciences, especially zoology and botany, where the evolution of species is shown as a succession of mutations and adaptations whereby new species are born out of the older ones. It seems that the use of genealogical trees in biology is justified, or at least acceptable. Now, can languages be compared to living organisms? Do they undergo mutations? Can they be classified into family trees? In this blog, I have already stressed the fact that there are no inherent components in languages that make them change. It is speech communities that change, causing hybridization and other phenomena that affect language. It is hard to imagine how a given speech community would just split into two without the actual intervention of external factors. Following this line of thought, it is clear that language family trees are just an inaccurate account of how languages evolve. However, an advocate of these trees may argue that the new approaches to language change, like the ones proposed by Mario Alinei, can be incorporated to the old theory, so that the idea of family relationships, with the whole array of divisions and branches, can still be maintained, at least to a certain extent. This way, for example, the division of language A into A1 and A2 is not just the consequence of a simple ‘mutation’ but the result of a combination of social and historical factors. Family trees are saved: there’s nothing specially wrong about them, and they’re visually attractive and very useful for pedagogical reasons. No problem then... Really? I’m not so sure.

First, a question: what can we see when we look at an IE genealogical tree? Does it depict the history of IE languages or, rather, the history of the written languages belonging to the IE group? The main concern of traditional historical linguistics has been the study of the written texts that have reached us from the past. Most of the principles and rules that have been proposed to describe the genealogical relationships between the various IE languages are based on this type of analysis. Is this an acceptable way to understand the ‘evolution’ of languages? I think it isn’t.

Let’s imagine a given geographic area, where there is written evidence of an old, now extinct language (Language A): by carefully studying the texts and all the available information, we can produce a description of the grammar, vocabulary and phonology of this language. We also find a second 'language' in the area (we will call it Language A2), whose written documents belong to a different period, about 500 years later. This language has a lot in common with its predecessor (Language A) but shows some clear signs of ‘evolution’. In Language A, for example, we find the words “pata” and “bolún”. Five centuries later, in Language A2, we have "peita" and "bulún". Apparently, the facts are clear: Language A has evolved into Language A2, and we can even devise a series of 'laws' that govern these changes. No problem. End of story. Or maybe not... As I said earlier, traditional IE theories and chronology are mainly based on the 'evolution' of written standards. However, if we apply a sociolinguistic approach to diachronic studies we get a different picture. Written languages originate in the dialect spoken by the ruling elite. Their social prestige and their association with power turn them into a very influential factor that affects the language of the whole society, but we can imagine that in a stratified society this written standard is not ‘the language’ (take a look at this post for a similar analysis). Let's turn now to Language A2 in our example. What is it exactly? Is it the result of an evolution process from Language A? Or is it a standard language connected with a different ruling elite that emerged later in the historical record? How do we know that the features of Language A are 'older' than the features of Language A2? The only thing we know is that they’re different standardized languages used at different times. Mario Alinei, in the framework of the Continuity Theory, is one of the first linguists who have analysed historical linguistics from a sociolinguistic perspective. He takes into account the written evidence and the traditional analysis but he puts them in a completely new context. His research on Italian dialects, for example, shows that some traditional assumptions about the emergence of Romance dialects in Italy cannot be accepted any more, as we have already seen in this post. A similar type of analysis could be applied to other languages.